**2. Phenology of sesame**

Sesame is a survivor crop. For 5500 years it has been planted by subsistence growers in areas that will not support the growth of other crops or under very difficult growing conditions with drought and/or high heat. In some countries, it is grown after the monsoon season on residual moisture with no rains during the production stage while in other areas it is grown during the monsoon season and subject to daily rains during the growing season. In several countries, it is the last crop that can be grown at the edge of deserts where no other crops grow. Very little sesame is grown under high input conditions [18].

placenta attachment has dried, and in many varieties, the capsules also may have a dark seed line on one side as shown in **Figure 2**. However, there is world germplasm

*The capsule on the bottom has seed that is milky white and is not mature. The capsule on the top has seed with*

There are cultivars where the yellowish green color of the capsule will indicate that the seed inside the capsule is at PM. However, there are other cultivars where the capsules are dark green with PM seed inside, and still other cultivars where the capsules are a pale yellow with immature seed inside. Before using capsule color to

The concept of PM in sesame was developed in the 1950s (M.L. Kinman, personal communication, 1982) to determine the earliest date that the plants could be cut and still harvest over 95% of the potential yield. When the seed has the final color, the seed can germinate. If the sesame is cut at PM, most of the seed with a greater than 75% darker color will continue maturing sufficiently for germination

*PM seeds have a brown tip (red arrow) where the placenta attachment has dried and on one side of the seed, a*

where the seed line is present but not visible without a magnifying glass.

*Effects of Harvest Aids on Sesame (*Sesamum indicum *L.) Drydown and Maturity*

*DOI: http://dx.doi.org/10.5772/intechopen.91011*

tell PM, the grower must be familiar with the cultivar.

**Figure 1.**

**Figure 2.**

**209**

*seed line is visible (blue arrow) (Photo: D.R. Langham).*

*final color (Photo: J. Riney).*

There are four phases in the phenology of sesame: vegetative, reproductive, ripening, and drying and there is a tremendous amount of variability in these phases [19]. Sesame is an indeterminate species, and thus, there is an overlap between the reproductive, ripening, and drying phases [18]. Since this chapter deals with sesame desiccation only the ripening and drying phases will be discussed.

Technically, as an indeterminate species, sesame is in the ripening stage from the mid-bloom stage through the full maturity stage. Sesame starts self-defoliation in late bloom stage and leaves have mostly fallen off by the initial drydown stage. As the plant stops flowering and matures, the leaves will drop starting at the bottom of the plant. In some fields, the upper leaves can remain attached providing some photosynthesis for seed fill in the upper capsules. Generally, leaves will turn yellowish green before dropping [18].

The character of leaf drop is very important for mechanical harvest and for using harvest aids. There is world germplasm where the leaves do not drop and can remain green even with a dry, open capsule in the leaf axil. Through plant breeding, the ability to self-defoliate has been incorporated into germplasm in the Americas starting in Venezuela from the mid-1940s [20].

At PM, 75% of the capsules on the main stem have seed with final color (darker than the milky white of the immature seed) as shown in **Figure 1**. Most of the seed grown for edible purposes is a light color, but there are cultivars with brown and black seed. The darker colors at PM are easy to distinguish from the milky white immature seed. Physiological mature seed also will have a brown tip where the

*Effects of Harvest Aids on Sesame (*Sesamum indicum *L.) Drydown and Maturity DOI: http://dx.doi.org/10.5772/intechopen.91011*

#### **Figure 1.**

leaves, and/or seeds in the bin, the moisture will transfer from the weeds to the sesame [17]. Extensive work in Venezuela to dry sesame by passing it through dryers showed that it was too expensive and that if more than 1% of moisture was removed per pass through the machines, the seed quality deteriorated to an unmarketable level (MAVESA representatives, personal communication,

• Glyphosate, carfentrazone-ethyl, and pyraflufen-ethyl are non-selective herbicides that will kill the sesame and the weeds; however, they are not desiccants. Among these, glyphosate is a better weed killer. Glyphosate should

• Paraquat-dichloride and diquat-dibromide are desiccants and may not kill

• Glufosinate-ammonium is a non-selective herbicide, but also will dry the

Sesame is a survivor crop. For 5500 years it has been planted by subsistence growers in areas that will not support the growth of other crops or under very difficult growing conditions with drought and/or high heat. In some countries, it is grown after the monsoon season on residual moisture with no rains during the production stage while in other areas it is grown during the monsoon season and subject to daily rains during the growing season. In several countries, it is the last crop that can be grown at the edge of deserts where no other crops grow. Very little

There are four phases in the phenology of sesame: vegetative, reproductive, ripening, and drying and there is a tremendous amount of variability in these phases [19]. Sesame is an indeterminate species, and thus, there is an overlap between the reproductive, ripening, and drying phases [18]. Since this chapter deals with sesame

Technically, as an indeterminate species, sesame is in the ripening stage from the mid-bloom stage through the full maturity stage. Sesame starts self-defoliation in late bloom stage and leaves have mostly fallen off by the initial drydown stage. As the plant stops flowering and matures, the leaves will drop starting at the bottom of the plant. In some fields, the upper leaves can remain attached providing some photosynthesis for seed fill in the upper capsules. Generally, leaves will turn

The character of leaf drop is very important for mechanical harvest and for using

At PM, 75% of the capsules on the main stem have seed with final color (darker than the milky white of the immature seed) as shown in **Figure 1**. Most of the seed grown for edible purposes is a light color, but there are cultivars with brown and black seed. The darker colors at PM are easy to distinguish from the milky white immature seed. Physiological mature seed also will have a brown tip where the

harvest aids. There is world germplasm where the leaves do not drop and can remain green even with a dry, open capsule in the leaf axil. Through plant breeding, the ability to self-defoliate has been incorporated into germplasm in the Americas

not be used for seed sesame because it can affect the germination.

*Pests, Weeds and Diseases in Agricultural Crop and Animal Husbandry Production*

weeds. They are based on contact with the sesame surface.

sesame down at a comparable rate to the desiccants.

• Tolerance to some herbicides is cultivar dependent.

sesame is grown under high input conditions [18].

yellowish green before dropping [18].

**208**

starting in Venezuela from the mid-1940s [20].

desiccation only the ripening and drying phases will be discussed.

1983).

**2. Phenology of sesame**

*The capsule on the bottom has seed that is milky white and is not mature. The capsule on the top has seed with final color (Photo: J. Riney).*

placenta attachment has dried, and in many varieties, the capsules also may have a dark seed line on one side as shown in **Figure 2**. However, there is world germplasm where the seed line is present but not visible without a magnifying glass.

There are cultivars where the yellowish green color of the capsule will indicate that the seed inside the capsule is at PM. However, there are other cultivars where the capsules are dark green with PM seed inside, and still other cultivars where the capsules are a pale yellow with immature seed inside. Before using capsule color to tell PM, the grower must be familiar with the cultivar.

The concept of PM in sesame was developed in the 1950s (M.L. Kinman, personal communication, 1982) to determine the earliest date that the plants could be cut and still harvest over 95% of the potential yield. When the seed has the final color, the seed can germinate. If the sesame is cut at PM, most of the seed with a greater than 75% darker color will continue maturing sufficiently for germination

#### **Figure 2.**

*PM seeds have a brown tip (red arrow) where the placenta attachment has dried and on one side of the seed, a seed line is visible (blue arrow) (Photo: D.R. Langham).*

but may be lighter in weight. Even in a fully mature plant, the seed weight produced at the top of the plant is lower; however, this loss of seed weight does not seriously affect the potential seed yield of the plant. Physiological maturity is important in the northern US crop where there is a potential for an early frost or freeze. After PM, most of the potential yield can be harvested, even if the plants were terminated by cold temperatures. In south Texas, the rule of thumb is that PM moves up 6–7 node pairs per week below the 75% PM level, and 4–5 node pairs per week above the 75% level. At higher latitudes where night temperatures are cooler, the progress of PM is 3–4 node pairs per week below the 75% level and 1–2 node pairs above it. The threshold temperature for growing degree days of sesame is 16°C. When night temperatures go below the threshold, it takes longer for the crop to mature. Physiological maturity also delineates the earliest time that harvest aids should be applied; applying them earlier will reduce potential yield.

The drying phase is divided into three stages: full maturity, initial drydown, and late drydown. Full maturity occurs from PM until 90% of the plants have all seeds mature. This stage usually occurs from 107 to 112 days after planting and lasts for approximately 1 week. With direct harvest, without the use of harvest aids, this stage is not important. With harvest aids, the plants will be killed, and the seeds will no longer fill. At the end of this stage, the plants will have the highest potential yield and can be terminated to accelerate drydown. However, since the capsules in the top 2–3 node pairs contribute little seed, the practical time to apply harvest aids may be at some point between PM and when all seeds are mature.

The above paragraphs show nominal days for one cultivar in the USA. There is a

Generally, if a cultivar starts flowering early, it will also stop flowering, mature,

Due to the shattering nature of the capsules, in most of the world, the sesame needs to be cut when green and shocked (stacking in bundles) so less seed will fall

Growers will cut the plants before the capsules start opening. Over 99% of the sesame harvest in the world involves some or total manual labor to cut the sesame, and no plants are left standing to dry in the field. Therefore, most of the sesame is harvested during or at the end of the ripening phase. Once shocked, the capsules will start drying and opening. Since the sesame is stacked and in a shock, which does not bend in the wind, most of the seed will stay in the capsules with some falling out of the top. In a commercial field in Venezuela, the author examined shocks that

*The plants are cut before the capsules start drying even though they have leaves and are not completely mature to*

and dry early. The point is that if a crop is left in the field to drydown without harvest aids, it takes about 5–6 weeks to be dry enough for a combine to harvest. If

**Phase Days from planting Length of phase, days**

*Effects of Harvest Aids on Sesame (*Sesamum indicum *L.) Drydown and Maturity*

Vegetative 29–59 42 29–59 42 Reproductive 56–116 89 16–70 47

Drying 102–181 150 11–57 38

*In some lines, there are dry capsules above green leaves while the upper part of the plant is still flowering creating*

**Range Mean Range Mean**

–54 11

range in the world germplasm planted in the USA (**Table 1**).

Ripening 77–140 108 (14)a

it is in the rainy season, it could take longer.

**3. Shattering nature of sesame**

*Range of days in phases for world germplasm.*

*DOI: http://dx.doi.org/10.5772/intechopen.91011*

*a*

**Table 1.**

**Figure 3.**

**211**

*the top (Photo: D.R. Langham).*

*a negative range.*

out as the plants dry (**Figures 3** and **4**).

The initial drydown stage occurs from the time all seeds are mature until the sesame plants have one dry capsule. This stage typically occurs 113–126 days after planting and can last for up to 2 weeks. This is a unique stage for most sesame that is grown in the Americas. In the world germplasm, a few cultivars have dry capsules with a green leaf in the same leaf axil, and many cultivars have a dry capsule when the top of the plant is still flowering. As a result, growers cut the plants to prevent seed loss and create a situation where some of the seed is mature and other seed is immature. In the Americas, the capsules do not drydown and open until flowering is complete and the majority of seed fill is complete. This character is described as "delayed shattering" (W. Wongyai, personal communication, 1998). Since sesame is basically indeterminate, the ability to stop flowering is difficult. There is germplasm that will stop flowering based on daylength; others that will stop based on cold nights; but most stop when they run out of moisture and/or fertility. The only problem with the latter germplasm is potential regrowth, which will be discussed later. A potential problem with delayed shattering is vivipary, which also will be discussed later.

The main stem will generally have dry capsules before the branches; however, the branches will generally drydown before the main stem. The lower capsules dry first with the top capsules drying last. There are some cultivars where the bottom capsules at the 2–3 node pairs drydown late even though the seed is at PM. Parts of the stem will dry before all the capsules are dry.

The late dry-down stage occurs from the time of the first capsule drydown until enough dry-down has occurred to produce 6% or less moisture seed. The first capsule drydown usually occurs 127 to 146 days after planting and the late drydown stage can last up to 3 wks. If the reproductive phase is shorter because of a lack of fertility, the first capsule drydown will occur a shorter time from planting but will not necessarily change the length of time of the late-drydown stage. However, if the reproductive phase is shorter because of a lack of moisture, the first capsule drydown will have a shorter time from planting and a shorter length of time of the late dry-down stage.

*Effects of Harvest Aids on Sesame (*Sesamum indicum *L.) Drydown and Maturity DOI: http://dx.doi.org/10.5772/intechopen.91011*

*a In some lines, there are dry capsules above green leaves while the upper part of the plant is still flowering creating a negative range.*

#### **Table 1.**

but may be lighter in weight. Even in a fully mature plant, the seed weight produced at the top of the plant is lower; however, this loss of seed weight does not seriously affect the potential seed yield of the plant. Physiological maturity is important in the northern US crop where there is a potential for an early frost or freeze. After PM, most of the potential yield can be harvested, even if the plants were terminated by cold temperatures. In south Texas, the rule of thumb is that PM moves up 6–7 node pairs per week below the 75% PM level, and 4–5 node pairs per week above the 75% level. At higher latitudes where night temperatures are cooler, the progress of PM is 3–4 node pairs per week below the 75% level and 1–2 node pairs above it. The threshold temperature for growing degree days of sesame is 16°C. When night temperatures go below the threshold, it takes longer for the crop to mature. Physiological maturity also delineates the earliest time that harvest aids should be applied; applying them earlier will reduce potential

*Pests, Weeds and Diseases in Agricultural Crop and Animal Husbandry Production*

The drying phase is divided into three stages: full maturity, initial drydown, and late drydown. Full maturity occurs from PM until 90% of the plants have all seeds mature. This stage usually occurs from 107 to 112 days after planting and lasts for approximately 1 week. With direct harvest, without the use of harvest aids, this stage is not important. With harvest aids, the plants will be killed, and the seeds will no longer fill. At the end of this stage, the plants will have the highest potential yield and can be terminated to accelerate drydown. However, since the capsules in the top 2–3 node pairs contribute little seed, the practical time to apply harvest aids may

The initial drydown stage occurs from the time all seeds are mature until the sesame plants have one dry capsule. This stage typically occurs 113–126 days after planting and can last for up to 2 weeks. This is a unique stage for most sesame that is grown in the Americas. In the world germplasm, a few cultivars have dry capsules with a green leaf in the same leaf axil, and many cultivars have a dry capsule when the top of the plant is still flowering. As a result, growers cut the plants to prevent seed loss and create a situation where some of the seed is mature and other seed is immature. In the Americas, the capsules do not drydown and open until flowering is complete and the majority of seed fill is complete. This character is described as "delayed shattering" (W. Wongyai, personal communication, 1998). Since sesame is basically indeterminate, the ability to stop flowering is difficult. There is germplasm that will stop flowering based on daylength; others that will stop based on cold nights; but most stop when they run out of moisture and/or fertility. The only problem with the latter germplasm is potential regrowth, which will be discussed later. A potential problem with delayed shattering is vivipary, which also will be

The main stem will generally have dry capsules before the branches; however, the branches will generally drydown before the main stem. The lower capsules dry first with the top capsules drying last. There are some cultivars where the bottom capsules at the 2–3 node pairs drydown late even though the seed is at PM. Parts of

The late dry-down stage occurs from the time of the first capsule drydown until

enough dry-down has occurred to produce 6% or less moisture seed. The first capsule drydown usually occurs 127 to 146 days after planting and the late drydown stage can last up to 3 wks. If the reproductive phase is shorter because of a lack of fertility, the first capsule drydown will occur a shorter time from planting but will not necessarily change the length of time of the late-drydown stage. However, if the reproductive phase is shorter because of a lack of moisture, the first capsule drydown will have a shorter time from planting and a shorter length of time

be at some point between PM and when all seeds are mature.

the stem will dry before all the capsules are dry.

yield.

discussed later.

of the late dry-down stage.

**210**

*Range of days in phases for world germplasm.*

The above paragraphs show nominal days for one cultivar in the USA. There is a range in the world germplasm planted in the USA (**Table 1**).

Generally, if a cultivar starts flowering early, it will also stop flowering, mature, and dry early. The point is that if a crop is left in the field to drydown without harvest aids, it takes about 5–6 weeks to be dry enough for a combine to harvest. If it is in the rainy season, it could take longer.

#### **3. Shattering nature of sesame**

Due to the shattering nature of the capsules, in most of the world, the sesame needs to be cut when green and shocked (stacking in bundles) so less seed will fall out as the plants dry (**Figures 3** and **4**).

Growers will cut the plants before the capsules start opening. Over 99% of the sesame harvest in the world involves some or total manual labor to cut the sesame, and no plants are left standing to dry in the field. Therefore, most of the sesame is harvested during or at the end of the ripening phase. Once shocked, the capsules will start drying and opening. Since the sesame is stacked and in a shock, which does not bend in the wind, most of the seed will stay in the capsules with some falling out of the top. In a commercial field in Venezuela, the author examined shocks that

#### **Figure 3.**

*The plants are cut before the capsules start drying even though they have leaves and are not completely mature to the top (Photo: D.R. Langham).*

#### **Figure 4.**

*The plants are placed in shocks to dry. The leaves shrivel quickly, but it will take about 2–3 weeks to dry, particularly in center of shock (Photo: D.R. Langham).*

were about 75% dry and found that about 10–15% of the seed had fallen out. That evening, it rained about 10 mm, and two days later the outer bundles in the shock had lost 20–40% of the seed, while the inside bundles which had not been wet were still at about 10–15% loss. **Figure 5** shows a similar Mexican commercial variety after a rain. Shattering is necessary for a manual harvest (**Figure 6**) where minimal force is used to get the seed out of the capsules.

direct may lead to as much as 90% loss of seed as discovered in 1978–1980 with

*Improved non-dehiscent capsule. These capsules hold their seed better and will still release it in the combine. This photo was taken on Dec 17 when the crop could have been combined the first week of Oct. The seed is still in*

*the capsules 76 days after the plants were dry enough for combining (Photo: D.R. Langham).*

*Shattering is essential to release seed as in this photo. Many growers hold the sesame plant upside down and hit with an implement. Some seed is lost while drying in the shock; other seed is lost in handling the sesame from the shock to the threshing area but upon threshing 95–100% of the remaining seed is collected (Photo: N. Smith).*

*Effects of Harvest Aids on Sesame (*Sesamum indicum *L.) Drydown and Maturity*

*DOI: http://dx.doi.org/10.5772/intechopen.91011*

In the 1940s, D.G. Langham [20] harvested sesame by using a binder to cut and bind the sesame at maturity. The sesame was manually shocked and when dry, the bundles were thrown into the combine header. Langham [21–23] discussed the history of improving shatter resistance in the USA. Basically by 1982, there was enough shatter resistance to be able to swath sesame into a windrow and leave it on

attempts to harvest shattering varieties left to dry in the field.

**Figure 6.**

**Figure 7.**

**213**

Since the 1940s, the goal in Venezuela and the USA has been to completely mechanize the sesame harvest. Leaving a shattering cultivar in the field to harvest

**Figure 5.** *More seed shattered out than usual with some capsules still green because of rain (Photo: D.R. Langham).*

*Effects of Harvest Aids on Sesame (*Sesamum indicum *L.) Drydown and Maturity DOI: http://dx.doi.org/10.5772/intechopen.91011*

#### **Figure 6.**

were about 75% dry and found that about 10–15% of the seed had fallen out. That evening, it rained about 10 mm, and two days later the outer bundles in the shock had lost 20–40% of the seed, while the inside bundles which had not been wet were still at about 10–15% loss. **Figure 5** shows a similar Mexican commercial variety after a rain. Shattering is necessary for a manual harvest (**Figure 6**) where minimal

*The plants are placed in shocks to dry. The leaves shrivel quickly, but it will take about 2–3 weeks to dry,*

*Pests, Weeds and Diseases in Agricultural Crop and Animal Husbandry Production*

Since the 1940s, the goal in Venezuela and the USA has been to completely mechanize the sesame harvest. Leaving a shattering cultivar in the field to harvest

*More seed shattered out than usual with some capsules still green because of rain (Photo: D.R. Langham).*

force is used to get the seed out of the capsules.

*particularly in center of shock (Photo: D.R. Langham).*

**Figure 4.**

**Figure 5.**

**212**

*Shattering is essential to release seed as in this photo. Many growers hold the sesame plant upside down and hit with an implement. Some seed is lost while drying in the shock; other seed is lost in handling the sesame from the shock to the threshing area but upon threshing 95–100% of the remaining seed is collected (Photo: N. Smith).*

direct may lead to as much as 90% loss of seed as discovered in 1978–1980 with attempts to harvest shattering varieties left to dry in the field.

In the 1940s, D.G. Langham [20] harvested sesame by using a binder to cut and bind the sesame at maturity. The sesame was manually shocked and when dry, the bundles were thrown into the combine header. Langham [21–23] discussed the history of improving shatter resistance in the USA. Basically by 1982, there was enough shatter resistance to be able to swath sesame into a windrow and leave it on

#### **Figure 7.**

*Improved non-dehiscent capsule. These capsules hold their seed better and will still release it in the combine. This photo was taken on Dec 17 when the crop could have been combined the first week of Oct. The seed is still in the capsules 76 days after the plants were dry enough for combining (Photo: D.R. Langham).*

the ground instead of shocking it manually. The windrows were harvested with a combine equipped with a pickup attachment. By 1988, the shatter resistance had improved to the point where the sesame could be left in the field to dry and then cut. The goal had been to have the seeds stay in the capsules until the combines arrived and then release the seed in the combine with a minimum of force. Improvements continued with the development of non-dehiscent sesame [24, 25] and later improved non-dehiscent sesame [25]. The seed would stay in the capsules through wind and rain even after the plants were dry enough to combine (**Figure 7**). for the stem to reach this moisture level leading to more seed loss in the field. Also, desiccation did not have an effect on defoliation, and the ability to harvest earlier through desiccation increased seed yield. In a grower book, Bennett et al. [32]

*Effects of Harvest Aids on Sesame (*Sesamum indicum *L.) Drydown and Maturity*

reduced shattering but seed loss was still evident even while waiting for sufficient drydown to spray (**Figure 8**). Also, there was still more loss when the cutter bar struck the sesame and the sesame was being moved by the auger into the feeder

Bennett and Routley [33] studied diquat-dibromide at 0, 1.4, 2.6, and 5.3 L ha1 and time of application (97 DAP with 40% green capsules, 103 DAP with 18% green capsules, 109 DAP with 0% green capsules, and untreated) in the 1993 and 1994 growing season using the sesame variety, Y1:44. Results indicated that application rates of 2.0 L ha1 were cost effective and that time of application should be between 20 and 40% green capsules. They also concluded that desiccation was a risk management tool. Sesame naturally drying down can be exposed for 30–40 days of various weather conditions, including rains and high winds**,** while a desiccated crop has a drydown of 7–10 days and, therefore, less of a chance of being exposed to inclement weather conditions. Also, desiccation allows the grower to

Mazzani [34] summarizing sesame research in Venezuela stated after almost 30 years of research and grower experience, the recommendations were to use diquat-dibromide at 1 kg ha1 at normal cutting time, which resulted in only a 15% lower yield over the untreated. Applying diquat-dibromide at 2 kg ha1 a week earlier than normal cutting time resulted in 97% seed loss due to immature seeds. The desiccation system is 4–8% of the cost of traditional system of cutting, binding, and shocking. Mazzani (personal communication, 1999) said that the timing of the herbicide application required grower experience of the sesame maturity stage based on capsule color and variety instead of number of days from emergence. Also, combining after using diquat-dibromide could be a bit earlier than the traditional method. Using the traditional shocking method, the inner bundles in the shocks take longer to drydown resulting in high risk, since the start of the monsoon season can occur while the sesame is still in shocks. One of the major advantages of using desiccants is that there is less manual labor available at harvest for cutting and shocking. On the negative side, the use of desiccants may produce less yield than the traditional method, particularly if there is a wind during drydown, which may cause

*Sesame on the ground even before combining from using dehiscent varieties (Photo: M. Bennett).*

. This application rate

recommended a diquat-dibromide application of 3 L ha1

*DOI: http://dx.doi.org/10.5772/intechopen.91011*

housing of the combine.

**Figure 8.**

**215**

plan for contract harvesting and trucks.


**2.2. The 9663 BP event**

Varve 10,430 BP was originally interpreted in terms of a "drainage varve" [16], an old idea now substituted by the recording of the huge earthquake in varve 10,430 BP and its extensive

**Figure 6.** Red dots represent sites of recorded tsunamites. Green field represents the spatial distribution of firmly varve-dated tsunamites, seismites and liquefaction features with sites outside this field referring to sites dated by other

**Figure 7.** Paleogeography of the land–sea–ice distribution at the time of the big earthquake in varve-year 10,430 BP (modified from [3]). Red dot marks location of epicentre. Red double arrows refer to the Närke Straight opened by the tsunami wave so that marine water could enter the Baltic and turn it into the Yoldia Sea stage. Red cross marks the location of two sites recording an earthquake event with liquefaction and a tsunami event occurring 67 varves after

means.

120 Tsunami

deglaciation [17].

tsunami event [1, 3, 4]. The spatial distribution is given in **Figures 6** and **7**.

In the Hudiksvall area of central Sweden, there occurred a very large earthquake in the varveyear 9663 BP [1, 3, 4, 9, 12, 18, 19]. The paleogeography of this event is very well known (**Figure 9**). Sea level was in the order of +224–230 m, and only minor islands stack out of the sea in front of the ice margin. It is recorded by multiple criteria [1, 4, 9] as illustrated in **Figure 8**. It seems to represent one of the best documented paleoseismic events in the world [1, 2]. The intensity was estimated at XII and the magnitude as >8 [2, 9]. Bedrock fracturing is recorded in some 100 sites over an area of 50 × 50 km. Liquefaction is recorded at 12 separate sites covering an area of 80 × 40 km. At two sites, it is recorded in five separate phases thought to represent the main event and a sequence of aftershocks. The liquefaction event is directly tied to varve 9663 BP. The water depth at the epicentre is likely to have been in the order of 250 m (allowing for a tsunami wave with the same diameter). A tsunami wave is recorded at 14 different sites, including nine lakes where a total of 44 cores were taken. It is dated both by varves (at 9663 varve-years BP) and by radiocarbon (at about 9150 C14-years BP). The tsunami wave must have a height of at least 15 m [1, 3, 4, 9]. A turbidite in varve 9663 BP extends for 310 km along the coast [1, 19].

**Figure 8.** The 9663 BP paleoseismic event must have had a magnitude of *M* > 8. It is documented by multiple criteria [1, 3, 4, 9, 18].

**Figure 9.** Paleogeography of the Hudiksvall area at the high-magnitude earthquake in the varve-year 9663 BP (or ∼9150 C14-years BP). Explanations: blue: extension of the ice cap; brown: land areas; black winding strings: eskers; red line with dot: fault line and location of epicentre; red dots with numbers 1–14: sites where tsunamites of the 9663 BP event have been documented (from [1]).

**Figure 9** provides the paleogeography of the area in the varve-year 9663 BP and the location of the 14 sites where records of the tsunami event have been recorded in the near-field region [1]. The area is traversed by six separate drainage basins marked by the corresponding esker systems from the subglacial drainage. The turbidite of varve 9663 BP traverses the entire area and expands 310 km to the south.

The tsunami was probably composed of two to three waves judging from the cycles recorded (**Figure 10**). Site 2 (Lake Svartsjön) is the key site of 14 closely spaced cores, five C14-dates and diatom analysis [1, 3]. The site was deglaciated 25 years before the tsunami event. The highest coastline (HK in **Figure 10**) was closely determined at +31.3 m. At the time of the tsunami event, the Baltic level had fallen to +223.5 m, i.e., a drop of about 7.8 m in 25 years, providing a rate of relative uplift of about 312 mm/year. The five C14-dates all overlap at 9155-9135 C14-years BP. A C14-age of 9150 BP would correspond to an absolute age of 10,350 cal. years BP. The deviation between the absolute age and the varve age of 9663 BP records an error in the varve chronology of about 700 years [20].

**Figure 10.** A 5.5 km SW–NE profile of the topographic setting of sites 2–5 (from [1]).

**Figure 9.** Paleogeography of the Hudiksvall area at the high-magnitude earthquake in the varve-year 9663 BP (or ∼9150 C14-years BP). Explanations: blue: extension of the ice cap; brown: land areas; black winding strings: eskers; red line with dot: fault line and location of epicentre; red dots with numbers 1–14: sites where tsunamites of the 9663 BP

**Figure 9** provides the paleogeography of the area in the varve-year 9663 BP and the location of the 14 sites where records of the tsunami event have been recorded in the near-field region [1]. The area is traversed by six separate drainage basins marked by the corresponding esker systems from the subglacial drainage. The turbidite of varve 9663 BP traverses the entire area

The tsunami was probably composed of two to three waves judging from the cycles recorded (**Figure 10**). Site 2 (Lake Svartsjön) is the key site of 14 closely spaced cores, five C14-dates and diatom analysis [1, 3]. The site was deglaciated 25 years before the tsunami event. The highest coastline (HK in **Figure 10**) was closely determined at +31.3 m. At the time of the tsunami event, the Baltic level had fallen to +223.5 m, i.e., a drop of about 7.8 m in 25 years, providing a rate of relative uplift of about 312 mm/year. The five C14-dates all overlap at 9155-9135 C14-years BP. A C14-age of 9150 BP would correspond to an absolute age of 10,350 cal. years BP. The deviation between the absolute age and the varve age of 9663 BP records an error in the varve

event have been documented (from [1]).

122 Tsunami

and expands 310 km to the south.

chronology of about 700 years [20].

**Figure 11** provides a good and representative record of the stratigraphy and sequence of events in Lake Svartsjön (Site 2). After the deposition of 25 varves, a tsunami wave invades the lake basin by overflowing the sill to the east (about +228 m) and depositing a thick tsunamite spread over the entire lake basin. This calls for a minimum height of the tsunami wave of 6 m (cf. 15 m at Site 3).

**Figure 11.** Stratigraphy, dates, tsunami characteristics and diatom analyses of Core 3 in Site 2 [1, 3]. The tsunamites spans 60 cm and is composed of a fragmentary first cycle and a full main cycle of graded bedding fining upward (sand-silt-clay). The diatom content of the tsunamite represents a planktonic deep-water flora of the open Baltic Lake Ancylus stage [3].

The tsunamite has a thickness 50–60 cm and is composed of two (occasionally 3) depositional cycles of graded bedding. The diatom flora of the tsunamite represents planktonic deep-water species from the open Baltic environment of the Ancylus Lake stage. This is a useful characteristic of sandy beds deposited by tsunami waves from the sea (contrary to shallow-water beach erosion).

The Lake Källsjön records are important [1]. This lake was never a part of the Baltic. The sill in-between had an original level of about +236 m [3] (**Figure 12**). Five cores were obtained in the lake, all including a typical tsunamite of graded bedding, indicating a forceful overflow of the sill and ingression into the lake of the 9663 BP tsunami wave. The wave must be at least 12.5 m high and overflow the sill for 700 m. Therefore, we can set the tsunami height at 13 m or rather about 15 m. The full evidence of a major tsunami event comes from the content of diatoms in the tsunamite beds, viz., a typical planktonic diatom flora of the Baltic Lake Ancylus stage [1, 3]. Furthermore, in today's lake, a small fish, smelt, is living, which is considered to be a relict from the Lake Ancylus stage of the Baltic, washed into the lake by the 9663 BP tsunami wave.

**Figure 12.** Site 3, Lake Kjällsjön, was never a part of the Baltic because it was located above the highest Baltic limit (BL) and separated from it by a sill [1, 3]. At the 9663 BP event, the sill was overwashed and the lake was invaded by a wave from the Baltic. The tsunami height must have been at least 13 m, probably about 15 m high. From [3].

A final example of the 9663 BP tsunami comes from the harbour of Iggesund (site 14 in **Figure 9**), where we had five pits and a major trench cut [1, 4]. The area was free-melted in 9747 BP. Then, followed the deposition on 84 annual varves. In varve-year 9663 BP, the area was affected by a strong earthquake. The glacifluvial sand and silt was heavily liquefied, and the liquefied material vented to the surface where it spread laterally by mushrooming. Some lateral spreading also occurred along the surfaces of varve beddings. In pits 4 and 5, the intraclay sand layer had the character of a tsunami bed. In pit 4, we brushed off the sand covering the clay surface beneath. The surface exposed was traversed by furrows and wave patterns (**Figure 13b**) indicating that the tsunamites must have been deposited by a flow from the NE, which implied from the sea towards the coast. At that stage, we had not yet located the epicentre of the paleoseismic event. Later it was determined that the epicentre of the 9663 BP event must have been located 12 km to the NE (as marked in **Figure 9**). Consequently, our sedimentary records in the pits at Iggesund (**Figure 13**) are in full agreement with this location of the epicentre.

The tsunamite has a thickness 50–60 cm and is composed of two (occasionally 3) depositional cycles of graded bedding. The diatom flora of the tsunamite represents planktonic deep-water species from the open Baltic environment of the Ancylus Lake stage. This is a useful characteristic of sandy beds deposited by tsunami waves from the sea (contrary to shallow-water

The Lake Källsjön records are important [1]. This lake was never a part of the Baltic. The sill in-between had an original level of about +236 m [3] (**Figure 12**). Five cores were obtained in the lake, all including a typical tsunamite of graded bedding, indicating a forceful overflow of the sill and ingression into the lake of the 9663 BP tsunami wave. The wave must be at least 12.5 m high and overflow the sill for 700 m. Therefore, we can set the tsunami height at 13 m or rather about 15 m. The full evidence of a major tsunami event comes from the content of diatoms in the tsunamite beds, viz., a typical planktonic diatom flora of the Baltic Lake Ancylus stage [1, 3]. Furthermore, in today's lake, a small fish, smelt, is living, which is considered to be a relict from the Lake Ancylus stage of the Baltic, washed into the lake by the 9663 BP tsunami

**Figure 12.** Site 3, Lake Kjällsjön, was never a part of the Baltic because it was located above the highest Baltic limit (BL) and separated from it by a sill [1, 3]. At the 9663 BP event, the sill was overwashed and the lake was invaded by a wave

A final example of the 9663 BP tsunami comes from the harbour of Iggesund (site 14 in **Figure 9**), where we had five pits and a major trench cut [1, 4]. The area was free-melted in 9747 BP. Then, followed the deposition on 84 annual varves. In varve-year 9663 BP, the area was affected by a strong earthquake. The glacifluvial sand and silt was heavily liquefied, and the liquefied material vented to the surface where it spread laterally by mushrooming. Some lateral spreading also occurred along the surfaces of varve beddings. In pits 4 and 5, the intraclay sand layer had the character of a tsunami bed. In pit 4, we brushed off the sand covering

from the Baltic. The tsunami height must have been at least 13 m, probably about 15 m high. From [3].

beach erosion).

124 Tsunami

wave.

**Figure 13.** Stratigraphic records at site 14, Iggesund harbour [1, 4] recording liquefaction, venting and surface mushrooming of liquefied material, and the deposition of a tsunamite. The clay surface beneath the tsunamite in pit 4 is irregular (furrows and waves) in a manner indicative of a deposition from the NE (from right to left), i.e. from the sea outside.

**Figure 14** provides the spatial distribution of the 9663 BP tsunami event in Sweden. The extension of this tsunami even will surely expand considerably with time to sites in Finland, Sweden and the Baltic coast to the SE, where there are numerous sites of proposed transgression deposits of the Ancylus Lake dated at the same age as the tsunami. Most probably, several of these sites must be reinterpreted in terms of tsunamites [1].

**Figure 14.** Red dots represent sites of recorded tsunamites. Green field represents the spatial distribution of firmly varve-dated tsunamites (also seismites and liquefaction features) with sites outside this field referring to sites dated by other means.

#### **2.3. The Late Holocene events**

The 17 tsunami events recorded in Sweden over the last 13,000 years (**Figure 1**, **Table 1**) are fairly regularly distributed over time. In the past 4000 years, there were as many as seven events observed [3, 21, 22], three of those are discussed below.

This includes a revision of the previously assigned age of the Hudiksvall event; now re-dated at 2900 BP, instead of 2000 BP. This makes the two events synchronous though recorded 160 km apart.

#### **2.4. The 2900 BP event recorded at two sites 160 km apart**

Site 1 refers to a well recorded at Skålbo, north of Hudiksvall [1, 3, 22, 23]. Here, violent methane-venting tectonics set up a tsunami wave recorded in five bogs at +8, +14, +18, +23 and +38 m [1, 3, 9, 22]. Lake Dellen, 25 km to the west and today at +37 m has a submerged peat dated at about 2000 BP [3]. This age was used to determine the age of the event. At 2000 BP, sea level was at +18 m, implying a wave height of 20 m [1]. Consequently, the run-up must have been at least 20 m in order to invade the +38 m bog.

**Figure 14** provides the spatial distribution of the 9663 BP tsunami event in Sweden. The extension of this tsunami even will surely expand considerably with time to sites in Finland, Sweden and the Baltic coast to the SE, where there are numerous sites of proposed transgression deposits of the Ancylus Lake dated at the same age as the tsunami. Most probably, several

**Figure 14.** Red dots represent sites of recorded tsunamites. Green field represents the spatial distribution of firmly varve-dated tsunamites (also seismites and liquefaction features) with sites outside this field referring to sites dated by

The 17 tsunami events recorded in Sweden over the last 13,000 years (**Figure 1**, **Table 1**) are fairly regularly distributed over time. In the past 4000 years, there were as many as seven events

This includes a revision of the previously assigned age of the Hudiksvall event; now re-dated at 2900 BP, instead of 2000 BP. This makes the two events synchronous though recorded 160

Site 1 refers to a well recorded at Skålbo, north of Hudiksvall [1, 3, 22, 23]. Here, violent methane-venting tectonics set up a tsunami wave recorded in five bogs at +8, +14, +18, +23 and +38 m [1, 3, 9, 22]. Lake Dellen, 25 km to the west and today at +37 m has a submerged peat dated at about 2000 BP [3]. This age was used to determine the age of the event. At 2000 BP,

of these sites must be reinterpreted in terms of tsunamites [1].

other means.

126 Tsunami

km apart.

**2.3. The Late Holocene events**

observed [3, 21, 22], three of those are discussed below.

**2.4. The 2900 BP event recorded at two sites 160 km apart**

Later, I come to question the age determination, however. First, the Lake Dellen pounding may have nothing to do with the tsunami event. Second, we find no records of the 2900 BP event in the Hudiksvall lakes and no records of the 2000 BP event in the Forsmark lakes. Third, subsequent C14-dates of the lake deposits provide ages older than 2000 BP.

Now, it seems quite clear that the Hudiksvall event should be synchronized [23] with the Forsmark tsunami event closely dated at 2900 BP.

At 2900 BP, sea level in the Hudiksvall area would have been at +26 m [23]. This implies a tsunami height of at least 12 m (to deposit a tsunamite in the +38 m bog). The tsunami wave had a trimming effect of the seabed (i.e., erosion) down to at least +8 or 18 m below sea level at that time.

**Figure 15.** The 2900 C14-years BP tsunami event in northern Uppland with respect to the rate of land uplift and shore displacement over the last 4000 years (the oblique line of ∼7 m uplift per millennia passing through dated anchor points marked by blue dots). At 2900 C14-years BP, the shore was at +20.7 m with land above (yellow) and sea (blue) below as marked on the right side of the diagram. The stars mark tsunami beds recorded and dated in offshore sediments (all falling sharply at the 2900 BP level), in coastal deposits and in lakes and bogs on land where the tsunami beds have eroded down into the older sediments. The graph provides evidence of a tsunami event that deposited typical tsunami beds over a vertical range from −20 to +6 m.

The Forsmark event (**Figure 15**) refers to a tsunami event very closely C14-dated at 2900 BP, which was recorded in seven lakebeds in northern Uppland, 160 km to the south of the Hudiksvall records [3, 9, 22]. The lakes investigated and dated form a staircase in elevation, viz., +5.5, +10.8, +16.0, +16.0, +22.2, +22.5 and +24.7 m. At the time of the tsunami event, sea level was at +20.7 m, implying that four lakes were located below and three above sea level at 2900 BP (**Figure 15**). In all the lakebeds, we found nice tsunamites of sandy layers in graded bedding. A lakebed at +27.4 m [24] shows no sign of a tsunami ingression. Therefore, the upper limit of the tsunami event is set at about 26.5 m, indicating a tsunami height in the order of 6 m (and a submarine trimming depth of about 20 m).

Several lakes and bogs in the region had been investigated before [24–26], but none of those studies recorded the occurrence of tsunamites despite the fact that they are quite clearly present in the lakes at +5.5, +10.8, +16.0 and +22.5 m [26], all later cored and dated by the author, as shown in **Figure 15**.

Synchronizing the events recorded at Skålbo and Forsmark (**Figure 16**) implies a fall in tsunami height of 6 m over a distance of 160 km, which seems quite reasonable.

**Figure 16.** Synchronization of the tsunami events recorded at Skålbo (Hudiksvall) and at Forsmark (northern Uppland) at 2900 BP [23]; elevation of dated cores (red dots), sea level at 2900 BP (dark blue lines). The tsunami wave height of at least 12 m in Skålbo decreases to at least 6 m in Forsmark, i.e., a decrease of 6 m in 160 km. The basal trimming seems to go down at least 18 m below sea level.

#### **2.5. The AD 1174 event**

In SW Sweden, there are evidence of a young paleoseismic event with local faulting of the Viking shoreline. This implies a faulting post-dating the formation of this shoreline, known as PTM-10, and dated at 1000-950 BP [1, 22, 27]. A fault offset of 1.1 m is recorded [1, 22].

It seems highly likely that this earthquake also set up a tsunami wave, which buried two Viking ships in the ancient harbour of Galtabäck [27]. A C14-date of the ship gave 1172 ±73 cal. years AD [28], which is quite close to a major historical earthquake event in 1174 as recorded in chronicles [29]. The covering and burying of the two ships in silt are indicative of a very rapid (instantaneous) process that took the ship owners by surprise, fully in line with the process of a tsunami event.

Therefore, it was proposed [27] that, indeed, the earthquake set up a tsunami and that the event refers to the earthquake in 1174 mentioned in the chronicles [29], which corresponds to 776 cal. years BP.

Having established this, it is possible to re-evaluate a turbidite record from the Gullmar Fjord [30] 230 km to the NW in terms of a tsunamite (**Figure 17**).

**Figure 17.** The time/depth relations of core 9004 [30] and the position of the "turbidite" here revised in terms of a tsunamite of the 1174 AD earthquake event.

An inferred age of the "turbidite" in the Gullmar Fjord core of 1174 AD fits perfectly well with the time/depth curve of [30]. I therefore, quite confidently, re-evaluate this layer as a tsunamite of the 1174 paleoseismic event [27].


*3.2.1 Methodology of the proposed system in proteus simulator*

In Proteus software, the methodology of the system designed for a single filling station has been simulated locally to simulate the following functions:


**9. References**

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**19**

**Chitosan-DNA/siRNA**

 *Université de Montréal*

*Paulista- Brazil*

*1Canada 2Brazil 3China*

**Nanoparticles for Gene Therapy**

Mohamed Benderdour1 and Julio C. Fernandes1

Qin Shi1, Marcio J. Tiera2, Xiaoling Zhang3, Kerong Dai3,

*1Orthopedic Research Laboratory, Hôpital du Sacré-Cœur de Montréal*

*3The key laboratory of Stem Cell Biology, Institute of Health Sciences Shanghai Jiao Tong University School of Medicine (SJTUSM) & Shanghai Institutes for Biological Sciences (SIBS), Chinese Academy of Sciences (CAS)*

*2Departamento de Quimica e Ciencias Ambientais, UNESP-Universidade Estadual*

Human diseases can be treated by the transfer of therapeutic genes (transgene) into specific cells or tissues of patients to correct or supplement defective, causative genes. Gene therapy offers a solution to controlled and specific delivery of genetic materials (DNA and RNA) to targeted cells. The success of gene therapy depends on the ability to deliver these therapeutic materials to targeted site. Viral vectors (e.g. adenovirus) are very effective in term of transfection efficiency, but they have limitations *in vivo*, particularly by their safety concern and non tissue-specific transfection. Non-viral gene transfer systems are limited by their lower gene transfer efficiency, low tissue specificity and transient gene expression. Chitosan is a polysaccharide usually obtained from deacetylation of chitin, which may be extracted from various sources, particularly from exoskeletons of arthropods such as crustaceans. The goal of this chapter is to introduce the readers to chitosan as a DNA/small interfering RNA (siRNA) delivery vector, as well as different variable strategies to improve cellular transfection and its potential clinical application. the first section is to present of chapter (section 1). The second section presents the discussion about barriers to DNA/siRNA delivery *in vitro* and *in vivo*. It is important to have a clear overview of obstacles to the *in vivo* treatment with DNA/siRNAs. Different *in vivo* administration routes will encounter different physiological barriers, and complications may be furthered by different cells in organs and tissues (section 2). The third section provides the readers with an understanding of the key steps of cellular internalization of DNA/siRNA non-viral vectors. Internalization of non-viral vector-based DNA/siRNA delivery system into cells typically occurs through endocytosis (section 3). the fourth section describes chitosan as a vector for gene therapy (section 4) followed by chitosan structure and physicochemical

**1. Introduction**


**2.2. Age-related alterations and clinical consequences**

**Airway**: The anatomy and physiology of the airway are affected with the aging process. Tooth decay which is common in elderly may cause loose, dislodged and subsequently aspiration of the teeth during emergency procedures such as endotracheal intubation (ET). Esthetic operations and loss of teeth interfere with achieving a good face-mask seal. Pharynx becomes more dry and fragile and care must be taken to prevent profuse bleeding while using laryngoscope. Oral cavity tumors and macroglossia may limit visualization of the vocal cords. Usage of Miller blade can be considered [4]. Also, cervical osteoarthritis increases the risk for spinal cord injury. Excessive movement of the neck should be avoided.


**1. Introduction: the importance of goat milk, dairy products, and meat as a potential functional food**

Interest from the consumers as well as growing concerns for physical well-being and health have increased the demand for information about the consumption of healthier foods.

Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons

The intake of some active compounds present in food, the so-called nutraceuticals and functional foods, can be regarded as having beneficial effects (physical and mental) on certain functions in the human body, that go beyond their nutritional effects.

**3. Composition of goat milk**

and mineral compounds found in goat milk.

Milk and derived dairy products are considered an important constituent of a balanced diet. Milk, as the first food for mammals, supplies all the energy and nutrients needed forthe proper growth and development of the neonate. For all mammalians, the consumption of milk ends at the weaning period except in humans, which continue consuming milk throughout their life. The physical characteristics and composition of milk vary between species. Chemically, milk is a complex oil-in-water emulsion containing proteins, fats, carbohydrates (mainly lactose), and lower amounts of minerals, enzymes, cells, hormones, immunoglobulins, and vitamins. The information currently available on the composition of goat milk has been published in the form of reviews [11–13]. Authors are unanimous in recognizing that fresh milk composition has a dynamic nature that varies with several factors such as (a) genetics (e.g., species, breed, and individual); (b) stage of lactation; (c) health status of the individual animal; and (d)

Nutritional and Health Profile of Goat Products: Focus on Health Benefits of Goat Milk

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environmental factors (e.g., feed, climate, season, or method of milking) [14–16].

Approximate compositions of the milks of different animals are compared in **Table 1**.

The basic nutrient composition of goat milk resembles that of cow milk (**Table 1**). Both milks contain substantially higher amounts of proteins and minerals, but lower lactose content than human milk [17]. Nonetheless, goat milk has high concentrations of fat globules, which are smaller than those present in cow milk; these globule diameters average are approximately 3.6 and 3.0 μm against 4.0 μm, respectively [18, 19]. The smaller size of fat globules provides a smoother texture in goat's derived products. Furthermore, goat milk contains lower amounts of α1-casein conferring it a higher water-holding capacity and a lower viscosity [20, 21]. Despite all these properties, the flavor of goat's milk is peculiar and more intense in comparison to cow's milk, which can restrict the acceptance of its derivatives by consumers [21]. However, goat milk is more easily digested than cow milk due to the absence of agglutinins in the former [11].

Goat and cow milk differ essentially in their casein micelles (structure, composition, and size), the proportion of individual protein fractions and higher content of nonprotein nitrogen

**Composition Goat Cow Human** Energy (kcal) 70 69 68 Water (%) 87.5 87.7 86.7 Total solids (g) 12.2 12.3 12.3 Protein (%) 3.2 3.3 1.3 Fat (%) 4.0–4.5 3.8 4.1 Lactose (%) 4.6 4.7 7.2 Ash (g) 0.8 0.7 0.2

**Table 1.** Basic composition of different milks (mean values per 100g) (adapted from Yadav et al. [24]).

As technology and science advances, the fields of health and nutrition have focused on several emerging fields, namely nutrigenomics, or "personalized nutrition." The study of the human genome in order to comprehend cellular response to nutrients and bioactive compounds is a promising field of work, which should lead specific dietary recommendations to prevent or aid in the treatment of certain diseases. In fact, stroke, cancer, and atherosclerosis and the general risk of diseases may be somehow minimized by introducing proper preventive nutrition and functional foods/foods as part of a healthier lifestyle that includes a balanced diet and physical activity [1]. Ingesting a wide variety of foods, namely fruits, vegetables, whole grains, milk, meat, and eggs is one way to ensure the intake of certain bioactive compounds that are present in its constitution such as carotenoids, dietary fiber, fatty acids, flavonoids, isothiocyanates, minerals, phenolic acids, plant stanols/sterols, polyols, prebiotics and probiotics, phytoestrogens, soy protein, sulphides/thiols, and vitamins [2].

Functional foods are growing in reputation across the globe and are becoming a part of daily diet of consumers who are concerned with their health. The global market potential for functional foods and beverages has been estimated to be worth \$192 billion by 2020 [3]. However, the effectiveness of nutraceutical products in preventing diseases depends on preserving the stability, bioactivity, and bioavailability of the active ingredients [4]. Functional foods are found virtually in all food categories; however, some products are not widely available in the market [5].

Sheep and goat products (mainly meat and dairy) have interesting characteristics in their levels of flavor, taste, aromas, and leanness as well as the specific composition of fats, proteins, amino, and fatty acids and have been traditionally consumed in certain regions of the globe [6]. Additionally, the nutritional properties of goat milk and its lower allergenicity when compared to cow milk [7, 8] has sparked an interest in goat milk as a functional food, and it is now one of the current trends in healthy eating in developed countries [9]. Moreover, the use of milk with particular nutritional properties, alone or in combination with bacterial strains with probiotic properties and capable of producing physiologically active metabolites, might become one of the options for manufacturing new dairy functional beverages [10].


**3. Results**

#### *3.1. Preparation and Characterization of Cu-MOF/GOD@HA*

The preparation process of Cu-MOF/GOD@HA was shown in Figure 1A as described in the experimental section. GOD was firstly loaded into Cu-MOF by amide reaction between –COOH on the Cu-MOF and –NH2 on GOD. Then, Cu-MOF/GOD was coated by HA to avoid the leakage of GOD and to improve its biocompatibility as well as the targeting ability. The CDT mechanism of Cu-MOF/GOD@HA was shown in Figure 1B. After endocytosis into MCF-7 cells, i.e., the tumor cells, CDT process based on Cu-MOF/GOD@HA was triggered sequentially by GSH "AND" H2O2 in the cancer cell interior. In addition, GOD in Cu-MOF catalysis Glu to supply H2O2 to improve CDT efficacy.

Transmission electron microscope (TEM) images in Figure 2A,B illustrate the Cu-MOF with diameter of 63.32 ± 9.12 nm. SEM image and Elemental mapping of C, N, O and Cu of Cu-MOF confirmed the successful preparation (Figure S1A,B). From the EDS spectra from SEM, Cu-MOF were consisted of 1% Cu, 2% N, 5% O and 92% C. As shown in Figure 2C, the shells of loaded GOD and coated HA were 5 nm. Compared with Cu-MOF, the FT-IR spectra of Cu-MOF/GOD, Cu-MOF/GOD@HA and GOD showed bands at 1550 cm–1, attributed to vibrational stretches characteristic of GOD, indicating the successful loading of GOD (Figure S2A). Furthermore, the TGA analysis of Cu-MOF and Cu-MOF/GOD@HA further confirmed the GOD loading and HA coating (Figure S2B). From the TGA analysis, Cu-MOF/GOD@HA were consisted with 15.32% HA, 21.56% GOD and 63.12% Cu-MOF.

**Figure 2.** (**A**) TEM images of Cu-MOF. Scale bar: 50 nm. (**B**) The size distribution of Cu-MOF as measured by TEM image. ( **C**) TEM images of Cu-MOF/GOD@HA (Scale bar: 25 nm).

In order to confirm the successful preparation of Cu-MOF/GOD@HA, the UV-vis absorption spectra of the reaction mixture were recorded. The absorption-change of Cu-MOF, Cu-MOF/GOD and Cu-MOF/GOD@HA in the 600–900 nm region, indicating the successful assembly of Cu-MOF/GOD@HA is clearly seen in Figure 3A. The color of Cu-MOF and Cu-MOF/GOD@HA changed from sky blue to green, also indicating successful loading of GOD and coating of HA. Zeta potential values of the corresponding nanocomposites obtained in each step are shown in Figure 3B, where the Cu-MOF aqueous solution exhibits a potential of −10.03 ± 0.16 mV. The loading of GOD reduces the zeta potential to −4.84 ± 0.19 mV, implying the deprotonation of the –NH2 of the GOD. The increase of zeta potential to −7.84 ± 0.28 mV due to the presence of the –OH of HA [32,33]. Furthermore, the X-ray diffraction (XRD) spectra of Cu-MOF, Cu-MOF/GOD and Cu-MOF/GOD@HA indicates that the loading of GOD and coating of HA did not influence the crystal structure of Cu-MOF (Figure S3).

**Figure 3.** (**A**) UV-vis absorption spectra of Cu-MOF, Cu-MOF/GOD and Cu-MOF/GOD@HA (The concentrations of pending test samples were 100 μg mL–1). Inset in (**A**) shows the photographs of the solutions containing Cu-MOF, Cu-MOF/GOD and Cu-MOF/GOD@HA. (**B**) Zeta potential values of Cu-MOF, Cu-MOF/GOD and Cu-MOF/GOD@HA. (The concentrations of pending test samples are 200 μg mL–1).

#### *3.2. Depletion of GSH and Generation of H2O2*

In order to confirm the oxidation-reduction reactions between Cu-MOF and GSH, molar equivalents of Cu-MOF and GSH were mixed in an aqueous solution. It is clearly illustrated in Figure S4 that the absorption of Cu-MOF completely disappeared after reaction of Cu-MOF and GSH for ca. 2 min along with the formation of Cu(I)-MOF, and the color of the mixture of Cu-MOF and GSH turned from sky blue to white. This observation obviously demonstrated that the incubation of Cu-MOF with GSH facilitates the reduction of divalent Cu(II) in the Cu-MOF by GSH. In addition, compared with TEM image of Cu-MOF, Cu-MOF was collapsed after treatment with 10 mmol L–1 GSH (Figure S5), proving the reaction between GSH and Cu-MOF.

X-ray photoelectron spectroscopy (XPS) was also used to investigate the oxidationreduction reactions between Cu-MOF and GSH. XPS is a surface sensitive technique. Compared with Cu-MOF (Figure S6A), an obvious N1s peak was observed in the XPS spectra of Cu-MOF/GOD and Cu-MOF/GOD@HA (Figure S6B,C), further demonstrating the occurrence of GOD loading. After treatment by GSH, an obvious N1s peak appears in Cu-MOF due to the residues of GSH (Figure S6D). Furthermore, after treatment of GSH, the XPS analysis of Cu(I)-MOF only shows Cu(I) (932.7, 952.4 eV) peaks (Figure S6E), also

confirming the reduction of Cu-MOF by GSH. Moreover, Figure 3A also shows that after loading with GOD and coating with HA, the UV-vis absorption of between 600–900 nm is significantly reduced. Interestingly, the proportion of Cu(I) on the surface of Cu-MOF have increased after loading with GOD and coating with HA. As shown in Figure S6F–H, the valence state of Cu is "+1" or "+2", since the Cu 2p XPS spectra displayed peaks on Cu(II) (934.4 eV, 954.2 eV)/Cu(I) (932.7 eV, 952.4 eV). The existence of Cu(II)/Cu(I) redox pair provide a great potential for Fenton-like reactions. In the paramagnetic chemical state (Figure S6F–H), the Cu 2p3/2 XPS spectrum is quantitatively analyzed, and the Cu(II)/Cu(I) ratio of Cu-MOF is 1.2872. The Cu(II)/Cu(I) ratios on the surface of Cu-MOF/GOD and Cu-MOF/GOD@HA in Cu 2p3/2 XPS spectra are 1.0376 and 0.8744, respectively. Obviously, after loading with GOD and coating with HA, the proportion of Cu(I) on the surface of Cu-MOF increased, indicating that Cu(II) was reduced to Cu(I) during the assembly process on the surface of Cu-MOF. This phenomenon may shorten the reaction time from Cu-MOF to Cu(I)-MOF.

After reduction of Cu-MOF by GSH, Cu(I) moiety catalyzes H2O2 to generate ·OH via a Fenton-like reaction. The Cu(I)-MOF-involved CDT processes are investigated and demonstrated by observing the degradation methylene blue (MB) [34]. ·OH induced degradation of MB which may result in a significant decrement on the absorption of MB at the maximum wavelength of 663 nm. Figure 4A shows that the degradation results of MB under different conditions by incubation for 40 min. In the presence of only Cu(I)-MOF or H2O2, virtually no degradation of MB was observed. On the contrary, a remarkable degradation of MB was recorded by introducing H2O2 into the mixture containing MB and Cu(I)-MOF. In addition, in the presence of free Cu(I) and H2O2, no remarkable degradation of MB was observed within 40 min. Thus, compared with free Cu(I), Cu(I) activated from Cu-MOF has a higher catalytic performance. Moreover, Figure S7 shows that Cu-MOF could not react with H2O2 to generate ·OH to reduce the degradation of MB. This provides a clear evidence for the occurrence of the Cu-MOF involving in the cascade reactions in CDT process. First, divalent Cu(II) in Cu-MOF was activated by GSH to convert to monovalent Cu(I) in Cu(I)-MOF. Subsequently, Cu(I)-MOF catalyzes the generation of ·OH from H2O2. The absorption spectra of MB illustrating its time-dependent degradation is shown in Figure 4B. It is obvious that MB was completely degraded after incubation for 40 min.

The depletion of GSH by Cu-MOF and the generation of H2O2 by GOD were investigated. First of all, Cu-MOF were treated by excess GSH. The residual GSH was indicated by 5,5-dithiobis (2-nitrobenzoic acid) (DTNB), a kind of sulphydryl (–SH) indicator at different time points [35]. With the extended time, the characteristic absorbance at ~412 nm decreased, indicating the depletion of GSH. As shown in Figure S8A, the depletion capacity of GSH exhibits a concentration-dependent model. The fluorescence signals of Ampliflu Red were influenced by the change of H2O2 concentration [36]. Therefore, Ampliflu Red can be used to investigate the generation of H2O2. As shown in Figure S8B,C, the generation of H2O2 exhibits a time-dependent model and a Glu-concentration-dependent model. The catalytic reaction of GOD with glucose to produce gluconic acid and H2O2 will cause the pH of the aqueous solution to change. Therefore, after mixing Cu-MOF or Cu-MOF/GOD and Glu for different time, the pH change can reflect the catalytic performance of GOD in Cu-MOF/GOD. As shown in Figure S9, the pH values show a time-dependent mode and a concentration-dependent mode (Glu). These results indicate that GOD loaded in Cu-MOF/GOD still can catalyze Glu to produce H2O2.

**Figure 4.** Experimental demonstration of the mechanism for the CDT process with Cu-MOF as the nano-therapeutic agent. OH generated from the Fenton-like reaction between Cu(I)-MOF and H2O2 leads to the degradation of MB. (**A**) MB degradation after incubation for 40 min in the presence of Cu(I)-MOF, H2O2, H2O2+Cu(I)-MOF and H2O2+free Cu(I), respectively. (**B**) The time-dependent degradation process of MB in the presence of Cu(I)-MOF. MB: 5 μg mL–1, H2O2: 10 mmol L–1, Cu(I)-MOF: 200 μg mL–1 (Cu(I): 0.494 μg mL–1), free Cu(I): 0.494 μg mL–1, time interval: 5 min.


Figure 6 shows an elemental view of the surface of the Ni-Fe-Co-P-1 g/L CeO2 composite coating, wherein the Ce element diagram (Figure 6f) represents nano-CeO2 particles, and it can be seen that the alloying elements and the nano-CeO2 particles are uniformly distributed on the surface of the plating layer. Studies have shown that the uniform distribution of elements and particles is due to the improved corrosion resistance of the coating.

**Figure 5.** P mass fraction of coatings with different concentration of nano-CeO2 particles.

**Figure 6.** Elemental surface mapping of Ni-Fe-Co-P-1 g/L CeO2 composite coating:(**a**) the SEM image of the analyzed surface (**b**) Ni content; (**c**) Fe content; (**d**) Co content; (**e**) P content; and (**f**) Ce content.

#### *3.2. Plating Phase Structure*

Figure 7 is an XRD pattern of the coating obtained by X-ray diffraction test. It can be seen that the coating is a typical amorphous structure, and there is a significant diffuse scattering broadening peak (Ni (110)) between 42◦ and 48◦ in 2θ. The peak width of the diffraction peak of the nanocrystalline alloy coating did not produce obvious changes, and peak intensity changes were not obvious, indicating that the nano-CeO2 particles did not obviously change in the phase structure of Ni-Fe-Co-P coating. For the nickel-phosphorus coating, the crystal structure depends mainly on the P element content in the coating. The authors of [21] have shown that when P content is lower than 5%, it is usually crystalline structure, and when P content is higher than 6.5%, it becomes amorphous structure. In this test, since the prepared plating layer is a quaternary alloy plating layer, and the atomic structure, size, and electronegativity of Ni, Fe, Co, and P elements are largely different, the amorphous forming ability is enhanced. Therefore, the plating layer is still amorphous when the P content is low. It is generally believed that the amorphous coating has better corrosion resistance due to the absence of local electrochemical potential difference between crystal grains and grain boundaries in the crystalline coating [18].

**Figure 7.** XRD patterns of coatings with different concentration of nanometer CeO2 particles.

#### *3.3. Tafel Polarization Curve*

Figure 8 shows the polarization curves of the composite coatings in the 50 g/L NaCl solution. The corrosion parameters obtained by Cview 2 software and polarization curve epitaxy are shown in Table 4. It can be seen from Figure 8 that the anodic polarization process of the composite coating is hindered and a significant passivation behavior occurs, and the composite coating is obtained when the concentration of nano-CeO2 particles in the plating solution is 1 g/L. The passivation zone is significantly larger than the remaining composite coating. It can be seen from Figure 8 and Table 4, compared with the polarization curve of pure Ni-Fe-Co-P alloy coating, that the polarization curve of composite coating prepared by co-deposition of a certain number of nano-CeO2 particles by scanning electrodeposition technology moves up and left as a whole. With the increase of the concentration of nano-CeO2 particles in the plating solution, the self-corrosion potential is continuously shifted, and the corrosion current density is gradually reduced. When the concentration of nano-CeO2 particles is 1 g/L, the prepared Ni-Fe-Co-P-CeO2 composite coating has the most positive self-corrosion potential (−0.19372 V) and the minimum corrosion current density (1.5375 × 10−5 A·cm−2). While continuing to increase the concentration of nano-CeO2 particles, the corrosion potential is negatively shifted, and the corrosion current density is significantly increased, indicating that corrosion resistance has begun to decline. According to the principle of corrosion electrochemistry, the larger the corrosion potential is, the smaller the corrosion current density is, the smaller the corrosion tendency of the material

is, and the better the corrosion resistance is. Therefore, the concentration of nano-CeO2 particles is 1 g/L. The Ni-Fe-Co-P-CeO2 composite coating has the best corrosion resistance. Studies have shown that anodic polarization can slow metal corrosion, and the degree of anodic polarization directly affects the speed of the anode process [22]. Compared with the pure Ni-Fe-Co-P coating, the addition of nano-CeO2 particles increases the hindrance of the corrosion process of the nickel-based coating. The Ba and Bc of the polarization curve of the composite coating are increased compared with the coating of the undoped nano-CeO2 particles; especially, the blocking effect (Ba) of the anode is more significant. When excessive nano-CeO2 particles are added to the plating solution, too much rare earth oxide adsorbs on the surface of the substrate, hindering the adsorption of Ni, Co, and Fe element on the surface of the substrate, which hinders the deposition of particles, which is not conducive to the plating. The formation of its corrosion resistance has been weakened.

**Figure 8.** Polarization curves of coatings with different concentrations of nanometer CeO2 particles.

**Table 4.** Composition of plating solution.

#### *3.4. Analysis of Electrochemical Impedance Spectroscopy*

In order to further explore the mechanism of electrochemical corrosion of Ni-Fe-Co-P-CeO2 composite coating, more corrosion kinetic information is obtained. The AC impedance analysis of the composite coating is performed under open circuit potential. The electrochemical impedance spectrum obtained in Figure 9 is shown. The Nyquist diagram of the composite coating (Figure 9a) shows a single capacitive reactance arc characteristic, and the Bode diagram (Figure 9c) has only one peak, indicating that the time constant is 1, and the electrode reaction process is mainly affected by the charge [23]. The transfer effect also indicates that the corrosive medium only contacts the interface of the coating and does not penetrate into the surface of the substrate due to diffusion. It can be seen from the phase angle curve of the Bode diagram (Figure 9c) that the maximum phase angle of the Ni-Fe-Co-P-CeO2 composite coating is higher than that of the pure nickel-based coating (56.379). From the impedance curve (Figure 9b), the impedance modulus of the composite coating doped

with nano-CeO2 particles is higher than that of the undoped nano-CeO2 particles throughout the scanning frequency interval. This shows that the corrosion resistance of the Ni-Fe-Co-P alloy coating is effectively improved by co-depositing nano-CeO2 particles. It can also be seen from the Nyquist diagram of Figure 9 (Figure 9a) that the radius of the capacitive reactance of the Ni-Fe-Co-P-CeO2 composite coating is much larger than that of the Ni-Fe-Co-P alloy coating. When the concentration of nano-CeO2 particles is 1 g/L, the radius of the capacitive anti-arc is the largest, and the radius of the capacitive anti-arc is used as the characterization of the corrosion resistance of the coating. The larger the radius, the greater the resistance of charge transfer and the harder the corrosion reaction. This result shows that the Ni-Fe-Co-P-CeO2 composite coating has better corrosion resistance. The AC impedance spectrum is modeled by the equivalent circuit diagram shown in Figure 10 and fitted by Zview software. The obtained fitting data is shown in Table 5. In the equivalent circuit diagram, Rs is the resistance in the solution. Rp is a charge transfer resistor, CPE is a constant phase angle element, and its impedance is

$$Z = 1/\text{Y}\_0(\text{j}\omega)^{-n}$$

its type has two parameters: constant Y0, its dimension is Ω−1·cm−2·s−n; parameter n, dimensionless index. When n = 1, the CPE component is the ideal capacitor. When n = 0, the CPE component is pure resistance, and in the actual solution, n is between 0 and 1 [7]. Obviously, with the addition of nano-CeO2 particles, the charge transfer resistance of the composite coating increases first and then decreases but the charge transfer resistor (Rp) of the doped nano-CeO2 particles is always larger than that of the pure nickel-based coating, and the corrosion resistance is extremely high great improvement. When the concentration of nano-CeO2 particles in the plating solution is too large, the nano-CeO2 particles are easily agglomerated, and the inclusions formed are increased, resulting in loose coating structure, and the strengthening effect of the nano-CeO2 particles is weakened.

**Figure 9.** *Cont*.

**Figure 9.** Alternating current impedance method EIS of coatings with of coatings with different concentrations of nanometer CeO2 particles: (**a**) Nyquist diagram, (**b**) Bode diagram—impedance curve, and (**c**) Bode diagram—phase Angle curve.

**Figure 10.** Equivalent circuit diagram.

**Table 5.** Equivalent circuit diagram parameter value.

#### *3.5. Surface Morphology after Corrosion of the Coating*

The SEM photographs in Figure 11 (image type is SEI) shows the surface topography of the composite coating after corrosion. It can be seen that after 5 days of etching in 50 g/L NaCl solution, many micro-protrusions of different sizes appear on the surface of the coating, and the surface appears more frequently black corrosion product. A large number of narrow and shallow microcracks extend along the boundaries of the cell structure. The degree of corrosion of the composite coating with different concentrations of nano-CeO2 particles in the plating solution is different. Among them, the coating of undoped nano-CeO2 particles (Figure 11a) is most corroded, and a large amount of corrosion product is deposited on the surface. When the concentration of nano-CeO2 particles is 1 g/L (Figure 11c), the coating is the least corroded and has a stronger retarding effect on corrosive media.

Generally speaking, the corrosion of metal in NaCl solution is mainly due to the presence of Cl−, the Cl− radius is small, the penetrating ability is very strong, and the adsorption is unevenly in the vicinity of the boundary and the impurity, so that the local dissolution is dominant, and pitting micropores are formed. Even if the surface has a passivation film formed by the metal, Cl− can form a soluble compound with the cation of the passivation film, destroying the dynamic balance of dissolution and repair of the passivation film, causing the passivation film to be gradually eliminated and continue to be corroded, resulting in etching. The deepening of the hole can quickly become a corrosion pit. When sprayed electrodeposition is used to prepare Ni-Fe-Co-P alloy coating, it is always accompanied by hydrogen evolution reaction, which retards the discharge deposition of Ni, Co, and Fe elements, which leads to the formation of pinholes or pits on the surface of the coating. In addition, the transition elements are sprayed. During the electrodeposition process, the amount of hydrogen absorption is large. The hydrogen atoms that penetrate into the cell by diffusion will cause distortion of the cytoplasm, forming a large internal stress, and stress corrosion occurs during the corrosion process. After the corrosion, the surface of the plating layer is easily cracked [24]. Since the deposition process of the sprayed electrodeposited Ni-Fe-Co-P alloy coating is a process of uneven reduction and accumulation of Ni, Co, Fe, and P, the atomic size is different and the arrangement is different, which can only be disorderly stacked and reflected to the plating layer [25]. On the top, the cell material is relatively dispersed, which provides conditions for the diffusion of corrosive media, but the corrosion condition after the addition of nano-CeO2 particles is improved. The reason is: first, the filling effect of the nano-CeO2 particles between the coating boundaries makes the structure of the composite coating is more uniform and dense, the porosity is greatly reduced, and the rare earth elements have strong affinity with impurity elements such as O and H, and these impurity elements can be wrapped to form a rare earth composite phase, and the surface of the coating is dispersed. The composite phase coverage causes the permeation channel of Cl− ions to be effectively intercepted, thereby enhancing the corrosion resistance of the composite coating [26]. Secondly, because the potential of nano-CeO2 particles is in Ni, Co, and Fe metals, it is easy to form microscopic galvanic cells at the interface between nano-CeO2 particles and nickel-based alloy. Nano-CeO2 particles are used as the cathode, and Ni, Co, and Fe are the anode. This galvanic reaction changes the coating from local spot corrosion to uniform corrosion, which helps to slow down the corrosion. When the concentration of nano-CeO2 particles is too large, the metal ions are precipitated in a large amount as a complex, and the amount of precipitation increases, but the actual deposition rate decreases, and the corrosion tendency of the coating increases [27].

**Figure 11.** Surface morphology after plating corrosion: (**a**) Ni-Fe-Co-P; (**b**) Ni-Fe-Co-P-0.5 g/L CeO2; (**c**) Ni-Fe-Co-P-1 g/L CeO2; and (**d**) Ni-Fe-Co-P-1.5 g/L CeO2.

#### **4. Conclusions**

In this paper, a Ni-Fe-Co-P-CeO2 composite coating was prepared using the scanning electrodeposition technique. To explore the impact of the concentration of nano-CeO2 particles in the plating solution on the micro morphology, structure, and composition of the coating, and to study the strengthening mechanism of nano-CeO2 particles on the electrochemical corrosion behavior of Ni-Fe-Co-P alloy coating, the following conclusions were drawn:

**Author Contributions:** X.F. and S.D. designed the experiments; W.M., Q.W., and S.D. performed the experiments and analyzed the data; X.F. contributed reagents and materials. S.D. and W.M. wrote the paper; and X.F. and J.L. provided corrections on the original draft.

**Funding:** This research was funded by the China Postdoctoral Science Foundation (Grant number 2017M621665), the Postdoctoral Science Foundation of Jiangsu Province of China (Grant number 2018K022A), and Postgraduate Research and Practice Innovate Program of Jiangsu Province (Grant number SJCX19\_0145).

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**

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