**4. Topical nanocarriers for drug delivery into the posterior segment of the eyeball**

To date, different nanocarriers have proven to be capable technologies to circumvent most of the ocular barriers and effectively deliver drugs to the posterior segment of the eye. Their favorable physicochemical properties, such as the small size and adjustable surface, render them advantageous in targeting drugs to the retina. Although different administration routes have been analyzed, we consider that the topical route is the one of greatest interest because of its favorable characteristics such as its ease for the patient, a potentially better compliance, and lower incidence of serious complications than injected methods. The main topically proven nanocarriers are polymeric NPs, lipid nanoparticles, micelles, dendrimers, and liposomes.

#### **4.1 Polymeric nanoparticles**

Polymeric nanoparticles (PNPs) are colloidal particles (10–1000 nm) where the drug is uniformly distributed throughout the particle matrix (nanospheres) or encapsulated inside a polymer shell (nanocapsules) [82]. Synthetic and natural biocompatible polymers can be used to develop PNPs. The polymers used to generate PNPs for ocular applications have been made from poly(alkyl cyanoacrylates) [83, 84], polycaprolactone, chitosan (CS), hyaluronic acid (HA), Eudragit (RS100 and RL100), Carbopol, gelatin, poly(butyl cyanoacrylate), polylactic acid (PLA), and poly(lactic-co-glycolic acid) (PLGA) [57, 85].

In regard to topical PNPs for posterior segment drug delivery, we would like to highlight the study performed by Tahara K et al., where submicron-sized poly(D,Llactide-co-glycolide) (PLGA) nanoparticles were used to improve the efficiency of drug delivery to the retina through topically administered drugs. Chitosan and glycol chitosan (GCS), which are mucoadhesive polymers, and polysorbate 80

*Role of Novel Drug Delivery Vehicles in Nanobiomedicine*

intravitreal injection is used as a delivery pathway.

**3.4 Intravitreal injection**

ocular diseases.

**3.3 Periocular administration**

Although topical and systemic routes are convenient, the lack of adequate bioavailability and the failure to deliver therapeutic amounts of drugs into the retina prompted vision scientists to search for alternative routes of administration. Hence, specific oral or intravenous targeting systems are needed to transport molecules through the choroid and into deeper layers of the retina [43]. An example of a systemic drug for the treatment of retinal diseases is Visudyne, which is used in photodynamic therapy for the treatment of wet age-related macular degeneration (AMD) and central serous chorioretinopathy (CSC). However, owing to toxicity and delivery concerns, intravenous administration is not very common in treating

Although not very patient compliant, these routes are partly used to overcome

Nowadays, intravitreal injection is the preferred route for ocular delivery for the treatment of diseases of the retina. It offers important advantages over periocular injections as drug molecules are directly inserted into the vitreous chamber. This method involves the injection of a drug solution directly into the vitreous, via the pars plana, using a 30-Ga needle. Unlike other routes, intravitreal injection offers higher drug concentrations in the vitreous and the retina. The advantage of IVT injection is the circumvention of the blood-retinal barrier, which keeps most drugs out of the eye in the case of oral and systemic administrations [43]. Therefore, IVT administration is able to maximize the intraocular level of drugs in the vitreous and the retina while avoiding toxicities associated with systemic treatment [66–69]. The benefits of intravitreal therapies in retinal diseases have been well documented, and the current standard of care is the injection of a bolus of anti-VEGF into the vitreous cavity on a frequent basis. Such a large bolus of a drug has been associated with some side effects [70]. In addition, this administration procedure creates a typical curve with a large peak of drug concentrations and a rapid decay. Literature supports the fact that the half-life of anti-VEGFs, such as ranibizumab, is indeed very short (halflife = 2.6–4.0 days) [71], making it necessary to use a higher initial dose in order to exceed therapeutic levels so as to allow a longer 28-day treatment interval. Moreover, mathematical modeling demonstrates that the binding activity of 0.5 mg of ranibizumab is fivefold higher if given every 14 days instead of every 28 days [72].

the inefficiency of topical and systemic dosing in order to deliver therapeutic drug concentrations to the posterior segment of the eye globe. Moreover, systemic administration may lead to side effects, making it a less desirable delivery route for geriatric patients. Periocular routes include subconjunctival, subtenon, retrobulbar, and peribulbar administrations, and they are comparatively less invasive than intravitreal routes. Drugs administered by periocular injections can reach the posterior segment through three different pathways: the transscleral pathway, systemic circulation through the choroid, and the anterior pathway through the tear film, cornea, aqueous humor, and vitreous humor [63]. The administration of a drug via subtenon injection resulted in the highest and more sustained vitreous concentration of drug molecules compared to other periocular injections [64]. However, anterior segment complications have been described in some patients following periocular injections. The complications include ocular hypertension, cataract, hyphema, strabismus, and corneal decompensation [65]. Additionally, the concentration of many drugs, such as that of anti-angiogenic drugs, is better if an

**30**

(P80) were used as surface modifiers of PGLA nanoparticles since this substance increases the interaction of NPs with cells. Coumarin-6 was used as a model drug and a fluorescent marker. The in vivo fluorescence image analysis showed detectable fluorescence intensity of coumarin-6 in the retina of mice after its topical administration [86]. The author proposed that the delivery of coumarin-6 into the posterior segment was associated with ocular surface modifications induced by CS, GCS, or P80. However, they did not verify this hypothesis.

Another interesting work concerning topically administered PNPs for retinal drug delivery was the study performed by Binstock et al., where the penetration of charged fluorescent nanoparticles into rabbit eyes using hydrogel iontophoresis was evaluated. Polyacrylic hydrogels were loaded with charged nanoparticles. NP suspensions (20–45 nm) were administered using cathodal and anodal iontophoresis and applying a current intensity of 1.5 mA for 5 min at the central cornea and the sclera (pars plana). The mean fluorescence intensity in outer ocular tissues (cornea, conjunctiva, and sclera) was 2–3 times higher for positively charged NPs with anodal iontophoresis. In deeper ocular tissues (retina, choroid, ciliary body, and iris), the mean fluorescence intensity was 5–15 times higher for the negatively charged NPs with cathodal iontophoresis. The positively charged particles demonstrated better penetration into inner ocular tissues than negatively charged particles [87]. This work showed that hydrogel iontophoresis combined with charged nanoparticles could be a potential technique for effective retinal drug delivery, but the investigation will have to be broadened and the potential adverse events explored.

## **4.2 Lipid nanoparticles**

Three different types of lipid nanoparticles (LNPs) have been used for ophthalmic formulations: solid lipid nanoparticles (SLNPs), nanostructured lipid carriers (NLCs), and hybrid lipid nanoparticles. SLNPs are aqueous colloidal dispersions composed of solid lipids as a matrix material with the capacity to encapsulate hydrophilic and lipophilic drugs. SLNPs are provided with multiple advantages such as physical stability, protection of the encapsulated drug, controlled release, biocompatibility, feasible production, and the possibility of being sterilized by autoclaving [88–91]. On the other hand, SLNs have limited drug loading and expulsion for both hydrophilic and lipophilic drugs. Loaded drugs are usually located between fatty acid chains, in lipid layers, or in crystal imperfections [92]. NLCs consist of a mixture of solid and liquid lipids, and they exhibit a higher drug-loading capacity and longer stability than SLNPs [93]. Finally, hybrid lipid nanoparticles modified by multifunctional polymers [94] combine the merits of polymeric nanoparticles and lipid-based systems, which improve the pharmacokinetics and biodistribution of the loaded drug [95].

Experimentally, LNPs have been used for the delivery of substances to the posterior segment of the eye via corneal and non-corneal pathways. Araujo et al. [96] developed a nanometric (∼200 nm), unimodal, and negatively charged NLC loaded with the fluorescent lipid, Nile red (NR-NLC) marker and a drug, triamcinolone acetonide (TA). The method used for the construction of the NLC was high-pressure homogenization. After NR-NLC eyedrop instillation in mice, lipophilic actives were released into the posterior segment of the eye. Retinal fluorescence of Nile red gradually increased over time, peaking 40 min after administration and almost disappearing at 160 min. The authors suggested that the fluorescence component of NR-NLC reached the retina through the BRB via non-corneal routes (sclera and conjunctiva).

In the work of Balguri et al., SLNPs and NLCs loaded with indomethacin (IN) were prepared through a hot homogenization method. Additionally, CS was used to modify the surface of SLNPs in order to increase penetration. After the topical application of formulations in rabbits, the concentration of IN was evaluated in

**33**

**4.4 Dendrimers**

*Breaking down the Barrier: Topical Liposomes as Nanocarriers for Drug Delivery…*

are the corneal pathway and the conjunctival-scleral pathway [97].

Finally, SLNPs comprising Compritol® 888 ATO and a polyethylene glycol (PEG) core, into which KTZ is dissolved, were topically used in rabbits. These SLNPs were generated by using a hot high-pressure homogenization method. Ocular pharmacokinetic studies indicated 2.5-fold and 1.6-fold increases in the aqueous humor and the vitreous humor via the topical administration compared to KTZ suspensions, respectively. Additionally, SLNPs were safe for the ocular surfaces of the study rabbits, and cell viability assays showed nontoxicity [98].

Micelles (10–100 nm) comprise amphiphilic block copolymers above the critical micellar concentration with a hydrophobic core and a hydrophilic shell [99]. The preparation process of colloidal dispersions consists of the exposition of self-assembly oriented amphiphilic molecules in order to form core-shell monomer nanomicelles in a special solvent. These nanodispersions solubilize hydrophobic drugs by entrapping them within a mixed micellar hydrophobic core, resulting in clear aqueous formulations [100]. Micelles prevent or minimize drug degradation, improve drug permeation, increase the solubility and stability of drugs, and

Lately, nanomicelles/mixed nanomicelles loaded with different drugs such as dexamethasone [103, 104], voclosporin [105], and rapamycin [106] have been designed to reach the posterior segment of the eye. Liaw et al. [107] also demonstrated that micelles could be effective for intraocular gene delivery. In this work, pDNA with the lacZ gene was coupled to poly(ethylene oxide)-poly(propylene oxide) poly(ethylene oxide) (PEO-PPO-PEO) nonionic copolymeric micelles. Following topical administration, gene expression was detected around the rabbit iris, sclera, and conjunctiva, and it was also seen in the intraocular tissues of nude mice after topical application for 48 h. In another study, Cholkar et al. [108] optimized an aqueous micellar solution of isopropyl ester carrying the resolvin (RX-10045) prodrug. Ocular tissue distribution studies demonstrated significant drug concentrations in anterior ocular tissues. Moreover, RX-10008 (the active metabolite of RX-10045) was detected in the retina/choroid upon topical drop instillation in rabbits. Micelles appeared to follow the conjunctival-scleral pathway to reach the retina, and no evidence of ocular

damage after multiple dosing of this micellar solution was observed [108].

Dendrimers are highly branched treelike structures with a core and many side chain [109] moieties. The size of dendrimer nanoparticles is usually under 100 nm, and peripheral functional groups (neutral, negative, or positive) may suffer secondary surface modifications in order to improve their characteristics for

ocular tissues by using high-performance liquid chromatography (HPLC)-UV method. In vivo bioavailability studies demonstrated that the IN of the formulations (IN-SLNPs, IN-NLC, and IN-CS-NLC) reached the posterior ocular tissues 2 h posttopical application. Moreover, the IN-NLC showed higher drug-loading capability, higher entrapment efficiency, less drug expulsion, and, especially, the highest distribution concentrations of IN in deeper ocular tissues (vitreous humor, choroidretina, and sclera). In vitro corneal penetration studies showed that CS increased corneal penetration by twofold (IN-CS-NLC compound), possibly thanks to the enhanced interaction with the mucus of the eye, the increased cellular uptake, and even its internalization. On the basis of their results, the authors proposed that the main transport routes of IN-NLC to successfully deliver IN to the posterior segment

*DOI: http://dx.doi.org/10.5772/intechopen.86601*

**4.3 Polymeric micelles**

improve ocular bioavailability [101, 102].

*Breaking down the Barrier: Topical Liposomes as Nanocarriers for Drug Delivery… DOI: http://dx.doi.org/10.5772/intechopen.86601*

ocular tissues by using high-performance liquid chromatography (HPLC)-UV method. In vivo bioavailability studies demonstrated that the IN of the formulations (IN-SLNPs, IN-NLC, and IN-CS-NLC) reached the posterior ocular tissues 2 h posttopical application. Moreover, the IN-NLC showed higher drug-loading capability, higher entrapment efficiency, less drug expulsion, and, especially, the highest distribution concentrations of IN in deeper ocular tissues (vitreous humor, choroidretina, and sclera). In vitro corneal penetration studies showed that CS increased corneal penetration by twofold (IN-CS-NLC compound), possibly thanks to the enhanced interaction with the mucus of the eye, the increased cellular uptake, and even its internalization. On the basis of their results, the authors proposed that the main transport routes of IN-NLC to successfully deliver IN to the posterior segment are the corneal pathway and the conjunctival-scleral pathway [97].

Finally, SLNPs comprising Compritol® 888 ATO and a polyethylene glycol (PEG) core, into which KTZ is dissolved, were topically used in rabbits. These SLNPs were generated by using a hot high-pressure homogenization method. Ocular pharmacokinetic studies indicated 2.5-fold and 1.6-fold increases in the aqueous humor and the vitreous humor via the topical administration compared to KTZ suspensions, respectively. Additionally, SLNPs were safe for the ocular surfaces of the study rabbits, and cell viability assays showed nontoxicity [98].

## **4.3 Polymeric micelles**

*Role of Novel Drug Delivery Vehicles in Nanobiomedicine*

GCS, or P80. However, they did not verify this hypothesis.

(P80) were used as surface modifiers of PGLA nanoparticles since this substance increases the interaction of NPs with cells. Coumarin-6 was used as a model drug and a fluorescent marker. The in vivo fluorescence image analysis showed detectable fluorescence intensity of coumarin-6 in the retina of mice after its topical administration [86]. The author proposed that the delivery of coumarin-6 into the posterior segment was associated with ocular surface modifications induced by CS,

Another interesting work concerning topically administered PNPs for retinal drug delivery was the study performed by Binstock et al., where the penetration of charged fluorescent nanoparticles into rabbit eyes using hydrogel iontophoresis was evaluated. Polyacrylic hydrogels were loaded with charged nanoparticles. NP suspensions (20–45 nm) were administered using cathodal and anodal iontophoresis and applying a current intensity of 1.5 mA for 5 min at the central cornea and the sclera (pars plana). The mean fluorescence intensity in outer ocular tissues (cornea, conjunctiva, and sclera) was 2–3 times higher for positively charged NPs with anodal iontophoresis. In deeper ocular tissues (retina, choroid, ciliary body, and iris), the mean fluorescence intensity was 5–15 times higher for the negatively charged NPs with cathodal iontophoresis. The positively charged particles demonstrated better penetration into inner ocular tissues than negatively charged particles [87]. This work showed that hydrogel iontophoresis combined with charged nanoparticles could be a potential technique for effective retinal drug delivery, but the investiga-

tion will have to be broadened and the potential adverse events explored.

improve the pharmacokinetics and biodistribution of the loaded drug [95]. Experimentally, LNPs have been used for the delivery of substances to the posterior segment of the eye via corneal and non-corneal pathways. Araujo et al. [96] developed a nanometric (∼200 nm), unimodal, and negatively charged NLC loaded with the fluorescent lipid, Nile red (NR-NLC) marker and a drug, triamcinolone acetonide (TA). The method used for the construction of the NLC was high-pressure homogenization. After NR-NLC eyedrop instillation in mice, lipophilic actives were released into the posterior segment of the eye. Retinal fluorescence of Nile red gradually increased over time, peaking 40 min after administration and almost disappearing at 160 min. The authors suggested that the fluorescence component of NR-NLC reached the retina through the BRB via non-corneal routes (sclera and conjunctiva). In the work of Balguri et al., SLNPs and NLCs loaded with indomethacin (IN) were prepared through a hot homogenization method. Additionally, CS was used to modify the surface of SLNPs in order to increase penetration. After the topical application of formulations in rabbits, the concentration of IN was evaluated in

Three different types of lipid nanoparticles (LNPs) have been used for ophthalmic formulations: solid lipid nanoparticles (SLNPs), nanostructured lipid carriers (NLCs), and hybrid lipid nanoparticles. SLNPs are aqueous colloidal dispersions composed of solid lipids as a matrix material with the capacity to encapsulate hydrophilic and lipophilic drugs. SLNPs are provided with multiple advantages such as physical stability, protection of the encapsulated drug, controlled release, biocompatibility, feasible production, and the possibility of being sterilized by autoclaving [88–91]. On the other hand, SLNs have limited drug loading and expulsion for both hydrophilic and lipophilic drugs. Loaded drugs are usually located between fatty acid chains, in lipid layers, or in crystal imperfections [92]. NLCs consist of a mixture of solid and liquid lipids, and they exhibit a higher drug-loading capacity and longer stability than SLNPs [93]. Finally, hybrid lipid nanoparticles modified by multifunctional polymers [94] combine the merits of polymeric nanoparticles and lipid-based systems, which

**4.2 Lipid nanoparticles**

**32**

Micelles (10–100 nm) comprise amphiphilic block copolymers above the critical micellar concentration with a hydrophobic core and a hydrophilic shell [99]. The preparation process of colloidal dispersions consists of the exposition of self-assembly oriented amphiphilic molecules in order to form core-shell monomer nanomicelles in a special solvent. These nanodispersions solubilize hydrophobic drugs by entrapping them within a mixed micellar hydrophobic core, resulting in clear aqueous formulations [100]. Micelles prevent or minimize drug degradation, improve drug permeation, increase the solubility and stability of drugs, and improve ocular bioavailability [101, 102].

Lately, nanomicelles/mixed nanomicelles loaded with different drugs such as dexamethasone [103, 104], voclosporin [105], and rapamycin [106] have been designed to reach the posterior segment of the eye. Liaw et al. [107] also demonstrated that micelles could be effective for intraocular gene delivery. In this work, pDNA with the lacZ gene was coupled to poly(ethylene oxide)-poly(propylene oxide) poly(ethylene oxide) (PEO-PPO-PEO) nonionic copolymeric micelles. Following topical administration, gene expression was detected around the rabbit iris, sclera, and conjunctiva, and it was also seen in the intraocular tissues of nude mice after topical application for 48 h. In another study, Cholkar et al. [108] optimized an aqueous micellar solution of isopropyl ester carrying the resolvin (RX-10045) prodrug. Ocular tissue distribution studies demonstrated significant drug concentrations in anterior ocular tissues. Moreover, RX-10008 (the active metabolite of RX-10045) was detected in the retina/choroid upon topical drop instillation in rabbits. Micelles appeared to follow the conjunctival-scleral pathway to reach the retina, and no evidence of ocular damage after multiple dosing of this micellar solution was observed [108].

#### **4.4 Dendrimers**

Dendrimers are highly branched treelike structures with a core and many side chain [109] moieties. The size of dendrimer nanoparticles is usually under 100 nm, and peripheral functional groups (neutral, negative, or positive) may suffer secondary surface modifications in order to improve their characteristics for ophthalmic use [110]. Due to their enhanced aqueous solubility, a large variety of surface groups, and their nontoxic nature, polyamidoamine (PAMAM) dendrimers have been investigated the most in regard to ocular drug delivery [111, 112].

Yavuz et al. [113] generated various anionic dexamethasone (DEX)-PAMAM complexes and evaluated the delivery of DEX to the posterior segment following topical administration in rats. The ocular tissue distribution study in rabbit eyes showed that anionic DEX-PANAM dendrimers reach the highest concentration of DEX in the vitreous body, the retina-choroid, and the sclera compared to topical DEX suspension. In addition, in vitro studies demonstrated that dendrimers with peripheral carboxyl or hydroxyl functional groups rarely showed cytotoxicity. Transport study results showed that dendrimer complexation increases DEX transport across both corneal and scleral tissues. Additionally, dendrimers have proven their efficiency to release genetic material when topically administered [114].


**Rhizobacteria Isolated from Saline Soil Induce Systemic Tolerance in Wheat (***Triticum aestivum* **L.) against Salinity Stress**

**Noshin Ilyas 1,\* , Roomina Mazhar 1, Humaira Yasmin 2, Wajiha Khan 3 , Sumera Iqbal 4 , Hesham El Enshasy 5,6,7,\* and Daniel Joe Dailin 5,6**

Received: 8 June 2020; Accepted: 23 June 2020; Published: 10 July 2020

**Abstract:** Halo-tolerant plant growth-promoting rhizobacteria (PGPR) have the inherent potential to cope up with salinity. Thus, they can be used as an effective strategy in enhancing the productivity of saline agro-systems. In this study, a total of 50 isolates were screened from the rhizospheric soil of plants growing in the salt range of Pakistan. Out of these, four isolates were selected based on their salinity tolerance and plant growth promotion characters. These isolates (SR1. SR2, SR3, and SR4) were identified as *Bacillus* sp. (KF719179), *Azospirillum brasilense* (KJ194586), *Azospirillum lipoferum* (KJ434039), and *Pseudomonas stutzeri* (KJ685889) by 16S rDNA gene sequence analysis. In vitro, these strains, in alone and in a consortium, showed better production of compatible solute and phytohormones, including indole acetic acid (IAA), gibberellic acid (GA), cytokinin (CK), and abscisic acid (ABA), in culture conditions under salt stress. When tested for inoculation, the consortium of all four strains showed the best results in terms of improved plant biomass and relative water content. Consortium-inoculated wheat plants showed tolerance by reduced electrolyte leakage and increased production of chlorophyll a, b, and total chlorophyll, and osmolytes, including soluble sugar, proline, amino acids, and antioxidant enzymes (superoxide dismutase, catalase, peroxidase), upon exposure to salinity stress (150 mM NaCl). In conclusion, plant growth-promoting bacteria, isolated from salt-affected regions, have strong potential to mitigate the deleterious effects of salt stress in wheat crop, when inoculated. Therefore, this consortium can be used as potent inoculants for wheat crop under prevailing stress conditions.

**Keywords:** salinity; PGPR; wheat; compatible solutes; antioxidant enzymes


**Acknowledgements**

This work was supported and financed by the Portuguese Foundation for Science and Technology (FCT) under the project SCAPEFIRE PCIF/ MOS/0046/2017. This work was also under the research unit Linking Landscape, Environment, Agriculture and Food Research Centre (LEAF) UID/ AGR/04129/2020.


3. Theoretical solution

There is no published work on the theoretical solution for the octagonal billet until now. However, a theoretical solution can be approximated by solving the DE of heat transfer on an equivalent circular geometry. According to Figure 1, the selected radius of that circle was Re = 156.6 mm, as given by Eq. (5):

$$R\_{\varepsilon} = \frac{1 + \cos\left(\pi/8\right)}{2} R = 0.962\ 162.84 = 156.6\ \text{mm} \tag{5}$$

This radius is actually the mean value between the circumradius and in-radius of the octagon [25]. The circumradius R being equal to 162.84 mm makes the currently studied octagonal billet equivalent in size to a 250 � 300 mm2 billet produced in the Stomana plant, at Pernik, Bulgaria. Now the original problem can be converted into a heat-transfer problem of cylindrical geometry, and the DE together with the boundary conditions is formulated according to Eq. (6):

$$\begin{aligned} \frac{\partial T}{\partial t} &= a \left( \frac{\partial^2 T}{\partial r^2} + \frac{1}{r} \frac{\partial T}{\partial r} \right) \\\\ T &= T\_0, \quad t = 0; \quad \frac{\partial T}{\partial r} = 0, \quad r = 0; \quad -k \frac{\partial T}{\partial r} = h \left( T - T\_f \right), \quad r = R\_\epsilon \end{aligned} \tag{6}$$

A Numerical Solution Model for the Heat Transfer in Octagonal Billets DOI: http://dx.doi.org/10.5772/intechopen.84305

By variable transformation using Eq. (7)

$$
\Theta = \frac{T - T\_f}{T\_0 - T\_f} \tag{7}
$$

the boundary condition at r=Re becomes:

$$\frac{\partial \Theta}{\partial r} + \frac{h}{k} \Theta = 0, \ r = R\_\epsilon \tag{8}$$

In order to fulfill the boundary condition at r=Re according to Eq. (8), Eq. (9) has to be solved for β:

$$
\beta J\_1(\beta) = A \, J\_0(\beta), \,\,\, A = \frac{R\_\epsilon \, h}{k} \tag{9}
$$

where J0 and J1 are the Bessel functions of zero and first order, respectively.

This theoretical solution is presented in the book of Carslaw and Jaeger [26] and is followed here. There are an infinite number of values for β, which solve Eq. (9); nevertheless, the first six roots [26] are enough for the computations. In this way, the derived solution arrives in the form of Eq. (10):

$$\begin{aligned} \Theta &= \frac{T - T\_f}{T\_0 - T\_f} = \sum\_{n=1}^{\infty} \exp\left(-\beta\_n^{-2} \xi\right) \frac{2A \, f\_0(\beta\_n \, r/R\_\epsilon)}{\left(\beta\_n^{-2} + A^2\right) f\_0(\beta\_n)}\\ \xi &= \frac{a \, t}{R\_\epsilon}, \quad A = \frac{R\_\epsilon \, h}{k} \end{aligned} \tag{10}$$

Figure 2. Theoretical predictions of the temperature distribution in various positions in a cylindrical billet.

Eq. (10) was applied in order to compute the temperature distribution T(r,t) inside the equivalent to the octagonal geometry cylindrical billet; some results are depicted in Figure 2. In fact, the following parameters were used in these computations: thermal conductivity, k = 50 W/m/K; density, ρ = 7600 kg/m3 ; heat capacity, c = 400 J/kg/K; thermal diffusivity, α = k/(ρc) = 1.645 ˜ 10°5 m2 /s; heat transfer coefficient, h = 200 W/m/K; cooling water temperature,Tf = 30°C, and initial billet temperature,T0 = 500°C.


**5. Conclusions**

As a means of extending previous literature, this paper has analyzed the profitability of a significant number of SMA TTRs on a wider range of energy markets and a period that includes the ongoing COVID-19 pandemic.

Using daily data for Brent and WTI spot crude oil prices and for the energy fund XLE and splitting the data into a pre-pandemic window (1999–2019) and a "pandemic period" (January–March 2021), we employ 14,100 SMA crossover TTRs for the longer pre-pandemic period and 1575 SMA crossover TTRs for the shorter pandemic interval.

To the best of our knowledge, this is the first research attempt to investigate the effectiveness of technical indicators on both main crude oil markets, as well as on a relevant energy exchange traded fund, in comparative perspective between the pre-COVID-19 pandemic and the pandemic period.

Overall, we find that technical trading rules can achieve high abnormal returns for all three energy markets over the COVID-19 pandemic period (annualized excess returns over the BH strategy of approximately 20% for WTI, 284% for Brent, and 83% for XLE, without including transaction costs), and only for the Brent market, some small abnormal annualized excess returns (of about 2%) over the 21-years of pre-pandemic period.

However, these excess returns encountered over the pandemic period are not strong on the WTI and XLE markets when their significance is tested by the standard Brock et al. [25] bootstrapping methodology with 1000 iterations, while for Brent market, excess returns gained by TTRs hold strong in all subperiods against the standard bootstrapping methodology. Over the pandemic period, excess returns achieved by TTRs on the Brent market are still high in magnitude and remain statistically significant after transaction costs are included in estimations. Over the pre-pandemic period, the small excess returns achieved by some technical rules on the Brent market are eroded by transaction costs and thus have no economic value. Similar to Taylor [36], our findings could thus reflect a relationship between technical rules' performance and market conditions.

Nonetheless, the abnormal return achieved by the best-performing TTR on the Brent market over the 1 and 1 4 years of pandemic period no longer holds strong against White's [30] Reality Check test. Thus, we find that SMA TTRs are not consistently profitable in the three energy markets once the data-snooping bias is accounted for.

However, while our results allow us to confidently conclude on the weak form efficiency of the WTI crude oil and the XLE fund markets throughout the 1999–2021 period relative to the universe of TTRs that we apply, and also to sustain the conclusion that TTRs do not add value on the Brent market beyond what may be expected by chance over the pre-pandemic 1999–2019 period, we refrain to also attest the weak-form efficiency of the Brent market over the COVID-19 pandemic. We feel that the performance of TTRs on the Brent market during the pandemic period needs further investigation, as most technical trading strategies achieve high excess returns over the benchmark buy-and-hold strategy, these excess returns hold when their significance is checked by the standard bootstrapping method and are also unaffected by transaction costs. The excess return gained by the optimal TTR only disappears after adjustment for data snooping is accomplished via the employment of White's Reality Check procedure. In this particular situation, the RC test might be too conservative and thus prone to type II errors. By presenting the results of all 1575 tested TTRs on the Brent market over the pandemic interval (both with and without transaction costs), and by showing that an overwhelming number of these strategies have been able to achieve abnormal returns of high magnitude on the Brent market during the COVID-19 pandemic (96.20% of strategies are still substantially over-performing even after adjustment for trading costs is made and thus have economic value), we sustain that survivorship bias is already mitigated. The adjustment made on the bootstrap *p*-values via the RC procedure could thus be too severe.

Consequently, while similar to Psaradellis et al. [23], we did not encounter enough evidence to be able to reject the weak-form efficiency of the three energy markets (Brent crude, WTI and XLE) for the whole 1999–2021 period, it would be hazardous to completely dismiss the above argument in the case of the Brent crude oil market over the COVID-19 pandemic period, when TTRs seem to have benefited from the extreme evolutions that characterized the market. As such, future studies on the Brent market efficiency during crisis are needed to sustain the right policy formulation process.

This paper makes several contributions to the existing literature. The first contribution is to revisit the predictive ability and performance of technical trading rules (TTRs) on some oscillated energy markets. This is the first paper to include both main grades of crude oil (WTI and Brent crude) and a relevant energy fund, XLE, and to assess the trading rules' performance over two different subperiods: pre-COVID-19 (January 1999–December 2019) and COVID-19 (January 2020–March 2021). The second contribution thus consists in presenting proof of TTRs' performance during the historically turbulent COVID-19 pandemic period for crude oil markets. Previous studies mostly refer to the WTI crude oil and cover periods no more recent than year 2019. Other contributions consist in the large universe of tested TTRs (14,100 over the pre-pandemic period, and 1575 over the pandemic period, respectively) and also in estimating the relevancy of results by evaluating the performance of the universe of TTRs while considering both naïve [25] (Brock et al. random bootstrapping method—with 1000 iterations) and more severe methods of accounting for data snooping effects (White's Reality Check procedure—also based on 1000 iterations). In addition, this strategy allows easy comparison with previous findings that have employed one of the two (or both) techniques. A fifth contribution consists in also estimating the economic value of results by allowing for transaction costs, while a final contribution stems for the identification of distinct financialization process between the two main crude oil markets, WTI and Brent. As such, research findings further imply that there is evidence to the existence of a more intense financialization process within the WTI crude oil market, whereas the market for Brent seems to be more impacted by shifts in global supply and demand. This has important implications for both the right choice of oil price forecasting methods by policy issuers and also for identifying the accurate policy measures.

Policy makers must thus consider these market characteristics that the study encounters for effective oil price forecasts and for efficient policy issuance. Moreover, as the financialization of the WTI market and the approaching expiration date for WTI contracts for delivery in May 2020 [37], coupled with insufficient storage capacity have determined its historical and unforeseen plummet on April 2020 into uncharted negative territory [38] regulators of WTI commodity market (i.e., The U.S. Commodities Futures Trading Commission), should also consider tighter measures (i.e., mandatory reporting of high volume trades, short selling restrictions, etc.) to prevent the recurrence of such events.

**Author Contributions:** Conceptualization, C.T.; Data curation, C.T.; Investigation, C.T.; Methodology, A.A.; Software, A.A.; Validation, C.T.; Visualization, C.T.; Writing—original draft, C.T. Both authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Data for crude oil prices is publicly available from the Federal Reserve Bank of St. Louis's (FRED) database, which collects data from the U.S. Energy Information Administration, while data for XLE is publicly available from Yahoo! Finance.

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

#### **References**


2.1.2. Sensor Observation Model

The radar can provide range and bearing measurements of the target's centroid, and the observation model of kinematic (position) measurement can be described by

$$z\_k = \begin{bmatrix} r\_k \\ \beta\_k \end{bmatrix} = \begin{bmatrix} \sqrt{\mathbf{x}\_k^2 + \mathbf{y}\_k^2} + v\_{1,k} \\ \tan^{-1}(y\_k/\mathbf{x}\_k) + v\_{2,k} \end{bmatrix} = h(\mathbf{x}\_k) + \mathbf{v}\_k \tag{3}$$

where *h*(·) is the kinematic observation function and *rk* and β*k* represent noisy measurements of target range and bearing at time *k*, respectively. *vk* = *v*1,*k v*2,*k* T denotes the corresponding zero-mean observation noise with covariance matrix *R* = *E*[*vkv*T *k* ] = *diag*[σ2 *r*, σ2 β].

As shown in Figure 1, for the low-speed maritime target, the heading is almost aligned with the axial direction of the target body because of its limited maneuverability. Under this condition, the aspect angle φ*k* of the target can be obtained as

$$
\phi\_k = \theta\_k - \beta\_k \tag{4}
$$

where θ*k* = tan−1( . *yk*/ . *xk*) is the heading angle.

**Figure 1.** Illustration of target aspect angle.

An equivalent expression of aspect angle is in the form of

$$\phi\_k = \cos^{-1}\left(\frac{\langle pos\_k, vel\_k \rangle}{||pos\_k|| \cdot ||\text{vel}\_k||}\right) = \cos^{-1}\left(\frac{x\_k \dot{x}\_k + y\_k \dot{y}\_k}{\sqrt{x\_k^2 + y\_k^2}\sqrt{\dot{x}\_k^2 + \dot{y}\_k^2}}\right) \tag{5}$$

The 3D-SCM is an equivalent of the target in geometry space to the radar response in the electromagnetic field. It provides a concise and physically relevant description of the target's scattering through a set of representative scattering parts, and thus a more effective way to characterize the target's electromagnetic scattering behavior. The 3D-SCM consists of a set of scattering center with a specific position, amplitude and type parameters, and it can be represented by

$$\mathbf{S} = \{a\_{n\prime} \alpha\_{n\prime} \ge\_{n\prime} y\_{n\prime} z\_n\}\_{n=1}^{N} \tag{6}$$

where *an* is the amplitude of *n*th scattering center, α*n* is a frequency-dependent factor, (*xn*, *yn*, *zn*) is the corresponding 3D spatial position in the target body coordinates and *N* is the number of scatters involved in the model. For a specific target class *c*, the associated 3D-SCM can be denoted as *Sc*.

The whole target's backscattering with respect to radar instantaneous frequency *f*, viewing angles (i.e., azimuth angle φ and elevation angle γ) can be expressed as [13]

$$E(f\_{\boldsymbol{\gamma}}\boldsymbol{\phi}, \boldsymbol{\gamma}, \mathbf{S}) = \sum\_{n=1}^{N} \left( \mathbf{j}f / f\_{\boldsymbol{\varepsilon}} \right)^{a\_n} a\_n (\boldsymbol{\phi}, \boldsymbol{\gamma}) \cdot \exp \left( -\mathbf{j}4\pi (\mathbf{x}\_n \cos \boldsymbol{\gamma} \cos \boldsymbol{\phi} + y\_n \cos \boldsymbol{\gamma} \sin \boldsymbol{\phi} + z\_n \sin \boldsymbol{\gamma}) / \lambda \right) \tag{7}$$

where λ is the wavelength, *fc* is the central frequency of signal, j = √ −1 is the imaginary unit and *an*(φ, γ) represents the amplitude of *n*th scattering center which may change with φ and γ.

At a specific viewing angle of (φ, γ), the corresponding projection position of the *n*th scattering center at the down-range direction is

$$\tau\_n(\phi, \gamma) = x\_n \cos \gamma \cos \phi + y\_n \cos \gamma \sin \phi + z\_n \sin \gamma \tag{8}$$

Assuming that the bandwidth of the radar signal is *B* and the *i*th discrete frequency point is

$$f\_i = f\_\varepsilon - B / 2 + i \cdot \Delta F, \quad i = 0, 1, \cdots, I \tag{9}$$

where Δ*F* is the frequency interval and *I* + 1 is the total number of frequency points.

Then, the frequency response of the *i*th frequency point can be written as *Ei* = *E*(*fi*,φ, γ, *S*). After a direct operation of inverse discrete Fourier transform (IDFT) on frequency response sequence *E* = [*E*0, *E*1, ··· , *EI*], the desired HRRP can be immediately obtained.

When the target's motion is restricted on the 2D plane, the observation model of HRRP is represented as

$$\begin{array}{lcl} d &= \mathcal{g}(\phi, \mathbf{S}) + \mathfrak{n} \\ &= IDFT[E\_i = E(f\_i, \phi\_\prime \mathcal{y}\_\prime, \mathbf{S}), i = 0, 1, \cdots, I] + \mathfrak{n} \\ &= IDFT(E) + \mathfrak{n} \end{array} \tag{10}$$

where *d* denotes the (*I*+1)-dimensional measurement of the HRRP and each component of *d* corresponds to one range resolution cell, *g*(φ, *S*) - *IDFT*(*E*) denotes the compact form of observation function, *fi* and *S* are known parameters, γ ≈ 0, φ can be obtained through Equations (4) or (5) and *n* is the observation noise vector.


**5. References**

242 Olive Oil – Constituents, Quality, Health Properties and Bioconversions

From a marketing point of view, consumers' purchasing behaviour is affected by the presence of heterogenous preferences that are derived from their own needs. This is especially important when the consumer is faced with new products or innovations. With regard to olive oil, an agrofood product that is one of the main components of the well-known Mediterranean diet, this heterogeneity is still greater, given the lower consumer knowledge in relation to such a product. Nevertheless, it is not exclusive of markets in the first stages of adopting olive oil, but is also, to a lesser extent, present in countries with a stronger tradition of olive oil consumption. Thus, the majority of studies report a stronger role of extrinsic aspects over intrinsic attributes. In this context, price is the major factor affecting consumer behaviour. Nevertheless, when the consumer is familiar with the product, the country of origin is the

The results obtained here lead the authors to offer a number of implications for marketing management in the olive oil sector. Given the strong presence of olive oil in international markets, as well as production systems strongly linked to a specific area of origin, promoting familiarity or experience of the products could provide firms with an effective source of

In particular, for those markets with less knowledge of olive oil (e.g., the US or China) communication actions will be critical for increasing consumers' familiarity and consequently their knowledge about these products. Thus the objective of commercial communication should consider not only different perceptions of the product cues, but also the differences in product familiarity. In particular, for countries in which product knowledge is greater and consumers have greater knowledge of the intrinsic characteristics of the product, communication campaigns should aim to reinforce consumers' image of the product. In contrast, in countries where the product knowledge is more limited, communication should focus on raising the consumers' level of familiarity and knowledge. This will raise the consumer confidence and, by extension, their purchase intention (Laroche *et al*., 1996). In

1. *Campaign to raise awareness among producers and exporters of olive oil*. This first stage should focus on informing producers/exporters about the positive consequences that a favourable image of the area of origin can have for each firm in particular, and for the sector in general. It is necessary to improve training in marketing and communication, for producing and commercial firms, so that they adopt a market orientation approach. For instance, this is the case for Spanish olive oil. Such campaigns are necessary if Spanish olive oil wants to improve its international market penetration, in relation to

2. *Educational campaign aimed at consumers*. The main objective at this stage should be to inform the consumer about the area of origin, the olive oil's area characteristics, the production techniques, and so forth. In short, the objective should be to communicate to the consumer the sector's enormous experience in the cultivation of olive oil, and the quality and safety processes used to obtain the end product. This stage of the campaign should also include communication actions aimed at prescribers (e.g., restaurant owners, food specialists) so that they recommend the product to the end consumers

competitive advantage, because of the positive consequences for the product image.

general terms, such campaigns should be divided into four consecutive stages:

Italian olive oil.

(current and potential consumers).

**4. Conclusions and recommendations**

most influential aspect in determining consumer purchases.

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**13**

*Spain*

**New Olive-Pomace Oil Improved**

**by Hydrothermal Pre-Treatments**

F. Rubio-Senent and J. Fernández-Bolaños *Departamento de Biotecnología de los Alimentos, Instituto de la Grasa (CSIC), Avda, Seville,*

G. Rodríguez-Gutiérrez, A. Lama-Muñoz, M.V. Ruiz-Méndez,

*Instituto al Campus de Excelencia Internacional Agroalimentario, ceiA3*

The health properties of virgin olive oil (VOO) are well known in the Mediterranean Diet, in which VOO is the main source of fat (Boskou, 2000). The Mediterranean area provides 97% of the total olive production of the world and represents a major industry in the region (Aragon & Palancar, 2001). The fatty acid composition is not the only healthy component of olive oil; in addition, minor components have high biological activities (Pérez-Jiménez et al., 2007). From the olive oil by-product, the olive-pomace oil (OPO) is obtained. Recent studies have demonstrated the positive benefits of OPO on health, and these effects are due mainly to the presence of minor components (Ruiz-Gutiérrez et al., 2009). The new olive oil extraction processes in the olive mills make the extraction of OPO and the general utilisation of wastes more difficult. New thermal systems are proposed to pre-treat the olive oil wastes

The manufacturing process of olive oil has undergone evolutionary changes. The traditional discontinuous pressing process was initially replaced by continuous centrifugation, using a three-phase system and later a two-phase system. Depending on the different olive oil production method, there are different kinds of wastes. The classic production of olive oil generates three phases and two wastes: olive oil (20 %), solid waste (30 %) and aqueous liquor (50 %). The solid waste (olive cake or "orujo") is a combination of olive pulp and stones. The aqueous liquor comes from the vegetation water and the soft tissues of the olive fruits, with water added during processing (so-called "alpechin" or "olive-mill waste water"). The presence of large amounts of organic substances (oil, polyphenols, protein, polysaccharides, etc.) and mineral salts represents a significant problem for the treatment of

The use of a modern two-phase processing technique to which no water is added generates oil and a new by-product that is a combination of liquid and solid waste, called "alperujo", "alpeorujo" or "two-phase olive mill waste". This by-product is a high-humidity residue

**1. Introduction**

to facilitate their utilisation and OPO extraction.

**1.1 Olive oil extraction systems**

wastewater (Borja et al., 1997).


[10] Wang Z, Li Z, Gu Z, et al. Preparation, characterization and properties of starch-based wood adhesive. Carbohydrate Polymers. 2012;**88**(2):699-706

[11] Zhang Y, Ding L, Gu J, et al. Preparation and properties of a starch-based wood adhesive with high bonding strength and water resistance. Carbohydrate Polymers. 2015;**115**:32-37

[12] Imam SH, Gordon SH, Mao L, et al. Environmentally friendly wood adhesive from a renewable plant polymer: Characteristics and optimization. Polymer Degradation and Stability. 2001;**73**(3):529-533

[13] Zhao X, Peng L, Wang H, et al. Environment-friendly urea-oxidized starch adhesive with zero formaldehydeemission. Carbohydrate Polymers. 2018;**181**:1112-1118

[14] Ong HR, Khan MMR, Prasad DMR, et al. Palm kernel meal as a melamine urea formaldehyde adhesive filler for plywood applications. International Journal of Adhesion and Adhesives. 2018;**85**:8-14

[15] Khanjanzadeh H, Pirayesh H, Sepahvand S. Influence of walnut shell as filler on mechanical and physical properties of MDF improved by nano-SiO 2. Journal of the Indian Academy of Wood Science. 2014;**11**(1):15-20

[16] Pizzi A. Resorcinol adhesives. Handbook of Adhesive Technology. Taylor & Francis Group, LLC; 2003:599-613

[17] Zhou X, Pizzi A. Pine tannin based adhesive mixes for plywood. International Wood Products Journal. 2014;**5**(1):27-32

[18] Hojilla-Evangelista MP, Bean SR. Evaluation of sorghum flour as extender in plywood adhesives for sprayline coaters or foam extrusion.

**27**

*Wood Adhesive Fillers Used during the Manufacture of Wood Panel Products*

*DOI: http://dx.doi.org/10.5772/intechopen.91280*

Industrial Crops and Products.

[19] Kang H, Wang Z, Wang Y, et al. Development of mainly plant proteinderived plywood bioadhesives via soy protein isolate fiber self-reinforced soybean meal composites. Industrial Crops and Products. 2019;**133**:10-17

[20] Aydin I, Demirkir C, Colak S, et al. Utilization of bark flours as additive in plywood manufacturing. European Journal of Wood and Wood Products.

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*Wood Adhesive Fillers Used during the Manufacture of Wood Panel Products DOI: http://dx.doi.org/10.5772/intechopen.91280*

Industrial Crops and Products. 2011;**34**(1):1168-1172

[19] Kang H, Wang Z, Wang Y, et al. Development of mainly plant proteinderived plywood bioadhesives via soy protein isolate fiber self-reinforced soybean meal composites. Industrial Crops and Products. 2019;**133**:10-17

[20] Aydin I, Demirkir C, Colak S, et al. Utilization of bark flours as additive in plywood manufacturing. European Journal of Wood and Wood Products. 2017;**75**(1):63-69

[21] Olivares M, Aceituno H, Neiman G, et al. Lignin-modified phenolic adhesives for bonding radiata pine plywood. Forest Products Journal. 1995;**45**(1):63

**26**

*Fillers*

**References**

2005

[1] Dunky M. Adhesives in the wood industry. Handbook of Adhesive

properties of starch-based wood adhesive. Carbohydrate Polymers.

[11] Zhang Y, Ding L, Gu J, et al. Preparation and properties of a starch-based wood adhesive with high bonding strength and water resistance. Carbohydrate Polymers. 2015;**115**:32-37

[12] Imam SH, Gordon SH, Mao L, et al. Environmentally friendly wood adhesive from a renewable plant polymer: Characteristics and

[13] Zhao X, Peng L, Wang H, et al. Environment-friendly urea-oxidized starch adhesive with zero formaldehydeemission. Carbohydrate Polymers.

Stability. 2001;**73**(3):529-533

2018;**181**:1112-1118

2018;**85**:8-14

2003:599-613

2014;**5**(1):27-32

optimization. Polymer Degradation and

[14] Ong HR, Khan MMR, Prasad DMR, et al. Palm kernel meal as a melamine urea formaldehyde adhesive filler for plywood applications. International Journal of Adhesion and Adhesives.

[15] Khanjanzadeh H, Pirayesh H, Sepahvand S. Influence of walnut shell as filler on mechanical and physical properties of MDF improved by nano-SiO 2. Journal of the Indian Academy of

Wood Science. 2014;**11**(1):15-20

[16] Pizzi A. Resorcinol adhesives. Handbook of Adhesive Technology. Taylor & Francis Group, LLC;

[17] Zhou X, Pizzi A. Pine tannin based adhesive mixes for plywood. International Wood Products Journal.

[18] Hojilla-Evangelista MP, Bean SR. Evaluation of sorghum flour as extender in plywood adhesives for sprayline coaters or foam extrusion.

2012;**88**(2):699-706

[2] Frihart CR. Wood Adhesion and Adhesives. Boca Raton, FL: CRC Press;

[3] Dunky M, Pizzi A. Wood adhesives. Adhesion Science and Engineering. Elsevier Science BV; 2002. pp. 1039-1103

[4] Qiao L, Easteal AJ, Bolt CJ, et al. The effects of filler materials on poly (vinyl acetate) emulsion wood adhesives. Pigment & Resin Technology.

[5] Lei H, Du G, Pizzi A, Celzard A. Influence of nanoclay on ureaformaldehyde resins for wood adhesives and its model. Journal of Applied Polymer Science. 2008;**109**(4):2442-2451

[6] Zhou X, Pizzi A, Du G. The effect of nanoclay on melamine-urea-

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Technology. 2003;**2**:50

1999;**28**(6):326-330

**29**

**Chapter 3**

**Abstract**

*Giovani Otavio Rissi*

nanofillers, circular economy

**1.

Fillers for Packaging Applications

Packaging in general is frequently overlooked and demonized. The lack of educational programs and efficient waste treatment lead packaging to be treated as an environmental problem. However, packaging is an enabler of our society because it makes feasible the availability of any and every good, regardless of its production location. Furthermore, the packaging business plays a significant role in the global economy, following a continuous trend of growth. The use of fillers in various packaging types can be a valuable resource not only for reducing its cost but also improving its mechanical strength (therefore reducing the number of raw materials required for making that specific package), improving its visual properties to ensure customer attractiveness, creating new possibilities of use, and extending the shelf life of perishable foods. However, the use of fillers in packaging should be made in a

**Keywords:** packaging, packaging market, paper packaging, plastic packaging,

Before proceeding, it is worthwhile to make a little observation about the environment around you. Take a quick break and behold what surrounds you and

Unless you are reading this in the wild of nature, everything you see was made available through some sort of packaging, even the materials used in the construction

Also, everything you eat—regardless of being an ordinary meal or a gourmet delight—came to you via packaging entrusted to keep high food safety and hygiene standards. Even if one has a backyard or farm that provides a wide variety of fresh produce, at some point in time some packaged foods will be bought and

Now think about all medicines that are consumed by millions of people every day to keep their well-being and health. Without being noticed, packaging allows for one of the most noble uses: to provide a longer and healthier life. You may now have realized for the first time that life as we know it exists at current standards due to a powerful enabler: packaging. Some studies suggest an association between the quality of life in a certain location and the level of packaging development in the

The reason for this is simple: our society has developed in a way that knowledge and experimentation are part of everyday life. We are informed about the latest trends and we want to try new things. At the same time, just a small fraction of the goods we buy is produced in our vicinity. Most goods are produced thousands of

way that permits proper recovery and recycling after use.

of the place where you are were bundled, contained, or packed.

#### **Chapter 3**


**Abstract**

This chapter presents a collection of studies performed in the Amazon region that includes thematic products portraying its fluvial sensitivity to oil spills. The research addresses the intense Amazonian seasonal dynamics, as well as the environmental peculiarities of this singular ecosystem. Periodic changes caused by natural phenomena have a significant impact on not only flooded alluvial plains and riverine habitats but also on petroleum exploration, production, and transportation activities. Therefore, the implementation of tools to assess the potential impact of oil spills in the Amazonian rivers must be adjusted to the local conditions. The main deliverables of the research are (1) fluvial oil spill sensitivity index maps contemplating each phase of the hydrological cycle (low water, high water, receding water, and rising water), (2) a computational method to represent fluctuations of the seasonal inundation, and (3) a risk analysis method using linguistic rules for the construction of a risk matrix.

**Keywords:** Amazon region, fluvial sensitivity to oil spills, computational modeling, linguistic rules, risk matrix

## **1. Introduction**

The Amazon is a region characterized by ecologically complex environments subjected to constant and rapid seasonal changes. The environmental patterns that make up the Amazonian scenario are determined by the changes that occur in the different phases of its hydrological cycle. The seasonal dynamic is evidenced by the average annual variation of the waters between maximum drought and flood conditions, which is on the order of 10–12 meters and is associated with rainfall in the headwaters of the rivers of the region and the annual thaw of the Andean summer [1].

A significant quantity of sediments from the Andes slopes, as well as a high concentration of nutrients, is transported during the flood period. This is the

main contributor responsible for the productivity of Amazonian floodplains, in terrestrial and aquatic systems alike [2]. The resulting annual deposition of such sediments defines the fauna and flora, the geomorphology of the floodplain, biogeography, and patterns of human occupation [1].

The discovery and exploitation of oil and gas in the Central Amazon rainforest is a major challenge for sustainable development. Hydrocarbon transportation is an industrial enterprise that involves various potential environmental impacts, thus requiring interdisciplinary studies for risk assessment [3, 4].

The study area includes the flow route of crude oil, liquefied petroleum gas (LPG), and natural gas produced by Petrobras in the Petroleum Province of Urucu. Three pipelines are used to bring crude oil, LPG, and natural gas from Urucu to a terminal located in Coari. From there, crude oil and LPG are transported to Manaus by river, while natural gas is taken via a terrestrial gas pipeline. Thus, this region is susceptible to possible damages due to oil activities, which are a potential threat to environmental conservation in the areas under its influence [5, 6].

The major oil companies have intensified their programs of excellence in environmental management and operational safety in order to reduce the risk of accidents in the operations of exploration, production, and transportation of petroleum and its derivatives. Nevertheless, these accidents can occur in rivers or at sea, due to product spills during procedures of oil tanker reservoir cleaning or loading in terminals, which require standardized response procedures for such emergencies [7].

Thus, given that the Amazon region presents considerable environmental sensitivity to oil spills, there is a need to respond proactively to possible accidents. In order to do this, it was necessary to examine the list of features of its rivers and lakes and their corresponding sensitivity in more detail, in order to hierarchize them in terms of potential impacts [8]. As a result, Araújo et al. [9] defined the fluvial sensitivity index to oil spills, adapted to the corresponding features and consistent with the typical Amazonian seasonality.

Among the factors that influence the sensitivity of habitats to oil spills, the most important are (1) the degree to which affected areas are exposed to processes of natural removal, (2) biological productivity and recovering capability after oil impacts, (3) existing land-use practices, and (4) ease of oil spill cleaning [10]. The overall sensitivity of natural habitats to oil spillage is ranked according to the aforementioned factors in the context of the environmental sensitivity index (ESI). The use of ESI is fundamental for oil spill contingency planning.

The most sensitive habitats in the Amazon region are flooded forests. In fact, inundation causes seasonal differences in the water level and changes the landscape, which creates the need for production of a specific sensitivity index map for each season: low water, high water, receding water, and rising water. The areas occupied by flooded forests change with time, such that continuous monitoring is required through the collection, processing, and analysis of remote sensing data. These areas were first systematically studied in the last decade using LHH SAR images based on the multi-seasonal coverage of the JERS-1 satellite [11].

The global weather-independent coverage provided by the synthetic aperture radar (SAR) system onboard the JERS-1 satellite allowed end users to monitor the rapidly changing conditions in cloud-covered rainforest regions. This L-band, HH polarization system is best suited for flood mapping in rainforest-covered areas due to its capability to penetrate dense vegetation [12].

The JERS-1 satellite orbital arrangement favors the continuous monitoring of the Amazonian hydrological cycle. To do so, contiguous orbits on consecutive days are used.  Consequently, JERS-1 SAR data were instrumental in mapping inundation variation in space and time over large forested floodplain regions [14–18].

**65**

**Table 2.**

*Fonte: Petrobras [21].*

*Overview of Hydrological Dynamics and Geomorphological Aspects of the Amazon Region…*

stretch that covers Urucu, Coari, and Manaus, will be presented.

**Fluvial channel features River plain features**

2. Beaches along the banks 2. Dense flooded forest

**Transitional features between channel and river plain components**

4 Scarps/high banks in unconsolidated sediment

10b Scrub-shrub wetlands (swampland, lowland, bushland, field, etc.)

 Exposed beaches and sand/gravel bars Sheltered beaches and sand/gravel bars Exposed mud beaches and bars Sheltered mud beaches and bars River and lake confluence zones 10a Aquatic macrophyte bars

*Fluvial sensitivity index to oil spills of the Amazon region.*

3. Waterfalls 3. Bushland (lower-density forest)

well as the ease of operational implementation [8].

**Riverine features of the Amazon region**

precise characteristics) and islands

1. Holes 2. Lake outlets *Fonte: Petrobras [21].*

*Amazon region riverine features.*

**Table 1.**

1. River banks (large class subdivided into more

4. Riverine sand bars—beaches formed in the middle of the river, isolated from the shores

**Index Characteristic or feature** Man-made structure Rocky shoals Rapids/waterfalls

**2. Determination of the fluvial sensitivity index in the Amazon**

Since the beginning of the 1990s, Petrobras has verified that the methodology of drawing up maps of environmental sensitivity to oil spills, adopted by the National Oceanic and Atmospheric Administration (NOAA), adequately adapts to the Brazilian reality, due to its great acceptance and utilization in many countries, as

1. Exposed lake/plain

4. Herb or grass macrophyte bank/exposed plain, depending on the period, functions as a filter

In this chapter, a brief summary will be presented on how the main Amazon features were identified and hierarchized, with relevance to the determination of the environmental sensitivity to oil production and transportation activities. Next, the three approaches used in mapping the fluvial sensitivity index to oil spills, in the

*DOI: http://dx.doi.org/10.5772/intechopen.86592*

*Overview of Hydrological Dynamics and Geomorphological Aspects of the Amazon Region… DOI: http://dx.doi.org/10.5772/intechopen.86592*

In this chapter, a brief summary will be presented on how the main Amazon features were identified and hierarchized, with relevance to the determination of the environmental sensitivity to oil production and transportation activities. Next, the three approaches used in mapping the fluvial sensitivity index to oil spills, in the stretch that covers Urucu, Coari, and Manaus, will be presented.