**1. Historical background**

The word "dengue" is known to be derived from Swahili language "ki denga pepo", which illustrates the meaning as "sudden cramp like seizure". The signs and indications that are suggestive of this viral disease can be tracked back to Chinese Chin Dynasty (265–420 AD) where this infection was believed to be a type of water poison and reported to be linked with insects and water [1]. Some of the historical accounts for dengue fever states that about 500–600 years ago, it appeared from Africa while the first and foremost outbreak of this deadly disease reached other parts of world in 1780s [2]. The detection and isolation of dengue virus date backed to the World War II and it was documented in Japan for the first time in 1942 [3]. Dengue-like symptoms have been reported in early Chinese manuscripts which can be traced back to 992 and to 1600s in the West Indies [4]. In another report, Benjamin Rush observed the first detailed symptoms of dengue shock syndrome (now severe dengue) in 1780 during an outbreak in Philadelphia near Delaware River [5]. Similar disease symptoms were observed in North America along Atlantic coast during eighteenth–nineteenth centuries, on the Caribbean Islands and the Mississippi basin [6]. Bancroft reported for the first time that *Aedes aegypti* mosquito is vector of dengue virus [7]. However, modern research about dengue virus was not started until 1943–1944. For the first time culturing and isolation of this virus was performed from suckling mice brain [8].

restricted till 1950s. But due to the Second World War, transport of *Aedes* mosquitoes happened around the world which played a crucial role in the dissemination of the viruses. Now, approximately 2.5 billion people live in areas where there is a risk of dengue transmission [9–12].

Dengue Fever: A General Perspective http://dx.doi.org/10.5772/intechopen.81277 5

During 1850s, first case of dengue was documented in the Philippines and Thailand. Later, after 1980s large number of cases began to appear in the Caribbean and Latin America. Today, Dengue is endemic in at least 100 countries in Asia, the Pacific, the Americas, Africa, and the Caribbean. Dengue fever is reported to prevail in 26 states [13–15]. DENV-2 was the predominant serotype in dengue outbreaks that occurred before 2000 but DENV-3 was the predominant serotype between 2000 and 2009. After 2010, DENV-1 dominated global dengue outbreaks, and DENV-4 was the least frequently identified serotype [16, 17]. The geographical distribution of dengue with respect to countries has been shown in **Figure 1** which explains

Dengue virus spreads due to infected females of genus *Aedes*, significantly form *Aedes aegypti* and *Aedes albopictus*. There has been a serious concern amid public health departments. In newly invaded countries, *Aedes albopictus* would cause severe epidemics of arbovirus diseases (it is considered as a competent vector transmitting about 22 arboviruses), especially all four serotypes of dengue; however generally it is transmitted by *Aedes aegypti*. *Aedes albopictus* persists to spread, taking the place of *Aedes aegypti* in some areas. [18] *Aedes albopictus* might serve as a maintenance vector of dengue in non-urban areas of Pacific islands and Southeast Asia. *Aedes albopictus* is not considered an imperative urban dengue vector, but in a few countries where *Aedes aegypti* is not present, that is, the Seychelles, parts of China, Japan and Hawaii [18]. The biting females of *Aedes albopictus* were discovered firstly in 1999, in Southern Cameroon; it provoked survey in 2000 and then adults as well as breeding populations were identified in five major cities of the country mainly breeding in old tires imported from

*Aedes* is best known vectors of dengue fever and yellow fever. Some species of *Aedes* are also vectors of viral disease and filariasis [20]. Several serotypes of the dengue virus are carried to human beings via the bites of *Aedes* mosquitoes infected with dengue virus. *Aedes aegypti* is considered one of the most crucial vector whereas *Aedes niveus*, *Aedes albopictus* and *Aedes polynesiensis* have been reported as secondary vectors in most of the regions of the world [9]. *Aedes aegypti* and *Aedes albopictus* are known as the two primary vectors for transmitting the dengue in most parts of South Asia, including India. As the distribution of this affliction is concerned in respect to geographically, it is characteristically parallel to that of the principal vector species, *Aedes aegypti* [21]. Dengue mosquito is a subtropical and tropical species having distribution throughout the world [22]. Dengue virus spreads due to infected females of genus Aedes, specifically through *Aedes aegypti* in urban settings and *Aedes albopictus* in sylvatic areas [18]. *Aedes albopictus* (Diptera: *Culicidae*), is basically endemic to Pacific and Indian Oceanic islands, and from South-east Asia, it spread to America, Europe and Africa in recent decades dormant eggs in the tires. Venereal and possibly vertical transmission of dengue virus takes place by infected female of *Aedes aegypti* to its progeny (transovarian) and also

from infected male to the female during the process of copulation, respectively [23].

the current prevalence of this disease around the world [11].

Nigeria and USA which were infested with the mosquitoes [19].

**3. The vector**


**Author details**

To date, the assisted reproductive technology literature describing attempts to alter the microbiome in the reproductive tract in order to impact outcomes has been operating on a rudimentary understanding of this complex environment at best. However, this approach, although perhaps to blunt a tool at present, may indeed be an important key to altering both the microbiome and subsequently the immune system as we further explore enhancement of

Knowledge regarding the interactions between the microbiome and the human reproductive axis is growing rapidly. A deeper understanding of normal physiology, identification of different dysbioses, and characterizing the microbiome's impact on reproductive outcomes promise meaningful enhancements in clinical care. While much has been learned since the early contributions of Semmelweis, the most insightful and powerful findings may lie just

Although the reproductive tract microbiome remains relatively poorly understood in terms of its relationship to reproductive outcomes, there is a long history of attempting to influence it with the use of prophylactic antibiotics at the time of procedures during ART. This has been a practice ingrained since 1978, when it was suggested that contamination during ART procedures could negatively affect outcomes [101]. Because antiseptics, such as povidone iodine, can have a negative impact on embryos, antibiotics were turned to as a way of

A common time for antimicrobial prophylaxis is at the time of ET. Given the concern for colonization of the transfer catheter tip with microbiota from the upper genital tract, antibiotics have been proposed as a way to decrease inoculation of the uterine cavity and thereby increase pregnancy rates. Despite this widespread practice, relatively little data exist to support or

A recent Cochrane review analyzed randomized controlled trials in the literature that investigated antibiotics at ET [103]. Only four potential studies were identified, of which three were excluded. The remaining study reported on clinical pregnancy rates as the primary outcome. Although administration of antibiotics reduced microbial contamina‐ tion as defined by culture of ET catheter tips, the clinical pregnancy rate was 36% in those receiving antibiotics and 35.5% in those not receiving antibiotics (odds ratio 1.02, 95% confidence interval 0.66–1.58) [104]. The reviewers concluded that more evidence is needed

reproductive competence in assisted reproductive technology.

**5.6. Conclusion**

124 Genital Infections and Infertility

ahead [100].

**6. Antimicrobials and ART**

manipulating the microbiome [102].

with live birth as the primary outcome.

refute antibiotic use.

Reza Peymani\* and Alan DeCherney

\*Address all correspondence to<EMAIL_ADDRESS>
National Institutes of Health (NIH), Eunice Kennedy Shriver National Institute of Child Health and Human Development, Fertility and Infertility Branch, Bethesda, USA


**2. Different types of learning disabilities in Malaysia**

In Malaysia, the term learning disabilities is more commonly used than the term specific learning disabilities [3]. One of the common types of learning disabilities among children in Malaysia is dyslexia. The Ministry of Education Malaysia, through its Special Education Division, defines dyslexic individuals as those with intellectual functioning equivalent to or above typical students of similar age but who have significant difficulty in spelling, reading and writing [13].  Dyslexia is a type of neurodevelopmental disorder that affect basic literacy-related skills, especially spelling and reading. Dyslexia is easily recognizable once children start their formal schooling. Among the clear indicators of dyslexic children is they usually have significant reading, spelling and writing difficulties. When they write an alphabet letter, they usually write it in reverse order. Some dyslexic children spell backwards or miss an alphabet in their spelling out of their consciousness. Dyslexia is said to be due to a problem in phonological processing, which refers to the skill or ability to identify speech sounds and relate them to letters and words. Being able to distinguish the sound of letters and relating the sound to letters and words is one of the fundamental skills in language acquisition and comprehension. Dyslexic children, on the other hand, struggle to process the sound of letters and to attach meaning to both spoken and written language. Dyslexia can be comorbid, which means it can occur in combination with other types of neurodevelopmental disorders such as Autism Spectrum Disorder (ASD). Dyslexia is enormously varied and presents differently in every person. There are those who face problems

with decoding words for reading, while others have no problem with decoding, but comprehension is severely affected. Dyslexic children usually show no obvious defect in intelligence and have no impairments in hearing and sight.

It was reported that to date, there are no accurate statistics on the total number of children with dyslexia in Malaysia. However, according to the Ministry of Health portal (MyHealth) [14], it is estimated that between 4 and 8% of school-aged children in Malaysia have dyslexia. It was reported in a local newspaper [15] that Malaysia is in dire need of a broader education system and more awareness programmes for dyslexic children to avoid being misdiagnosed with other health conditions. According to the Dyslexia Malaysia Association, knowledge of dyslexia is still lacking among parents.

There have been some attempts to mitigate the dyslexia problem among school-going children in Malaysia. For example, the Special Education Division of the Ministry of Education [13] has developed a screening instrument known as Instrumen Senarai Semak Disleksia (Dyslexia Checklist Instrument). This is a local instrument that is used to screen students at the entry level of the primary schools suspected to have dyslexia and those who are at risk of having dyslexia. Those who are identified as probably having dyslexia are further referred to the medical or healthcare services for proper diagnosis. In addition, in 2010, the Ministry of Education Malaysia introduced the Literacy and Numeracy Screening programme (LINUS) [16], which is a programme developed for primary school children that focuses on ensuring each child masters their basic literacy and numeracy skills after following the first 3-year of primary education. Those who struggle with basic reading and writing skills at the entry level are placed in the LINUS programme. This is a type of intervention programme designed in remedial classes to give remedial to students' basic reading, writing and arithmetic problems.

Another type of learning disability is dyscalculia. In Malaysia, dyscalculia is not as well known as dyslexia. According to Fu and Chin [17] as cited in Aquil and Mohd Ariffin [18] knowledge of dyscalculia as well as awareness of the problem is still not widespread in Malaysia. The prevalence rate is also not known as there is very limited research evidence on the prevalence of dyscalculia in the whole of Malaysia [18]. Dyscalculia generally refers to the problem affecting the ability to comprehend the concept of numbers and to acquire arithmetic skills [19]. Children with dyscalculia usually have deficits in counting and calculating at many math levels, which are fundamental in mathematical acquisition, reasoning and knowledge. They are struggling with basic mathematical operation such as counting quantities, addition, multiplication, segregating the smaller or bigger numbers, etc. While dyslexia is a problem specific to spelling and writing, dyscalculia is a type of learning disability specifically affecting children' ability to understand and work with numbers. Some early signs of dyscalculia, as listed by Plerou [19], are the inability to memorize number sequence, difficulties in basic number counting, difficulties in number comparison and difficulties in connecting numbers to symbols (e.g., 3 = three).

The possible causes for dyscalculia are not fully understood, but research suggests some biological factors such as genetic factors and differences in brain structures responsible for processing numbers and mathematical concepts in individuals with dyscalculia [20]. Dyscalculia may happen in association with other types of learning disability such as Dyslexia and Dysgraphia. Children who have dyscalculia may continue to struggle as adults if no intervention is given to manage the difficulty. Despite the lack of knowledge and misconception of the problem with dyscalculia in Malaysia, efforts have been made to improve its identification and diagnosis to provide support for children with this type of learning disability. Currently, in Malaysia,

#### *Children with Learning Disabilities in Malaysia DOI: http://dx.doi.org/10.5772/intechopen.113230*

a standardized instrument that can be used in the diagnosis of dyscalculia is still lacking [21]. However, there have been some initiatives to develop local instruments that can be used as early identification system for dyscalculia. For example, Malaysian Dyscalculia Instrument Plus was developed as dyscalculia screener and CheckDysc©, which has been found to be able to provide early detection that can alert parents and teachers on the risk for dyscalculia in children [22]. As regard remedial measures for dyscalculia children, the use of mobile app learning has shown some positive effect of math learning. A study conducted by Ariffin et al. [23] reported that dyscalculia children have shown improvement in math learning following a mobile app learning named "Calculic Kids." Another local researcher [24] proposed "*i-Matematik"* in web-based courseware to teach mathematics to students who face difficulties with mathematics.

Dysgraphia is another type of learning disability that primarily affects another fundamental literacy skill: writing. Children with dysgraphia face significant difficulty in writing with clarity and accuracy. They face problems in skills to hand write, to spell words and to organize their thoughts on paper. Specifically, a form of dysgraphia known as motor dysgraphia is due to deficient fine motor skills that limit the children to produce legible handwriting. They are found to have awkward pencil grip and unspecified motor clumsiness [25]. In addition to significantly producing spelling mistakes when writing, they also experience challenges in forming or writing letters and words. Those with language-based or cognitive-based dysgraphia have trouble translating thoughts and ideas into written expression. As with other types of learning disabilities, dysgraphia can come in conjunction with dyslexia and dyscalculia as well as other pervasive developmental problems such as ASD and ADHD. Not much data on dysgraphia in Malaysia is available as very limited research on this problem is conducted. As awareness and knowledge about dysgraphia among the Malaysian community is very scarce, children with dysgraphia are sometimes misidentified as dyslexic. Based on the report from the Malaysian Welfare Department [26], children with dysgraphia also include those with dyslexia. To help children with dysgraphia a study conducted by [25] designed a dysgraphic-customized application called Write-Rite to support children with dysgraphia, which has been found to produce a positive effect on the children's handwriting performance.

Dyslexia, dyscalculia and dysgraphia represent significant impairments to a particular aspect of academic learning such as reading, calculating and writing. Two additional major disorders frequently linked to learning difficulties are Autism Spectrum Disorder (ASD) and Attention-Deficit Hyperactive Disorder (ADHD). ASD is a pervasive developmental disorder affecting an individual's social, communicative and language skills [27]. Ranging from mild to severe, children with ASD generally have cognitive disabilities that implicate their learning, memory ability and emotions [28]. The DSM 5 characterized those with ASD by their persistent impairment in social interaction and social communication skills such as deficits in social-emotional reciprocity as well as restricted and repetitive patterns of behaviors, activities or interests manifested by stereotyped motor movements and others. Children with ASD may appear passive because they are equally unable to use non-verbal communication. This harbors frustration, leading them to express themselves through tantrums, aggression or other inappropriate behaviours. Currently in Malaysia, no official number of ASD children can be found in the registry [29]. Part of the reason is that ASD cases are lumped together under the category of learning disabilities and other cognitive and developmental abilities [30]. The Ministry of Health Malaysia reported that ASD cases are on the rise, and they are detected mostly during early childhood

when children are already in school. Since there is no cure for ASD, early diagnosis and treatment can help improve the development of the child [2].

Another major disorder associated closely with learning disabilities is Attention-Deficit Hyperactive Disorder (ADHD). It is one of the most common neurodevelopmental disorders affecting an estimated 8–10% of school children [31]. The core symptoms of ADHD, as prescribed by DSM 5, are a persistent pattern of inattention and/or hyperactive and impulsive behavior that is more frequent and severe than is typically seen in a child at a given developmental stage and has caused significant functional impairment [32]. Their behavioural and emotional problems present a serious obstacle to the academic, social and emotional development of children with ADHD and negatively affect their adjustment to adult life. Generally, children diagnosed with ADHD will face problems with their ability to focus as they are very easily distracted and often lose concentration. Their impulsiveness and motor activity levels also present significant challenges in school settings. As reported in Ref. [32], the estimated prevalence of ADHD in Malaysia ranges from 1.6 to 4.6%, and boys are three to four times more likely to be diagnosed with ADHD than girls. Contributing factors to ADHD include both genetic and environmental factors such as traumatic brain injury and some prenatal factors. The Malaysian clinical practice guidelines prescribe that any child presenting with difficulties in academic have behavioral problems and mood disturbances should be evaluated for ADHD to prevent deleterious outcomes in adulthood [32].

### **3. Discussion and way forward**

The children of the nation are assets, so education is essential. As cited in Ref. [33], several declarations of the United Nations such as the Convention on the Rights of the Child, Convention on the Rights of Persons with Disabilities, and the Universal Declaration of Human Rights have explicitly stated the right for education to everyone including those with learning disabilities. It was further reported that in Malaysia, the educational rights for children with learning disabilities have been specifically provided under Section 28 of the Persons with Disabilities Act 2008, which states that children with learning disabilities should not be excluded from the general education system on the basis of their disabilities. Thus, regardless of their disabilities, an equal access to education must be granted to them.

Various initiatives have been taken by the Malaysian government to confer educational rights for children with learning disabilities. Among the positive steps taken by the Ministry of Education, through its Special Education Division are to make available special education programme for those with special needs. Under this programme, special schools for students with visual and hearing impairments as well as those with learning disabilities are developed. In addition, the special education integration programme places students with special needs in special classes in mainstream schools while in the inclusive education programme, children with special needs learn the same curriculum and are placed in the same class as normal students. The effort in preparing LINUS screening and intervention programmes is indeed a positive step toward the early identification of students with learning disabilities in Malaysia. These are among the initiatives taken by the government to ensure children with different types of disabilities have equal education opportunities as other normal children. As reported in Ref. [33], according to the 2021 report by the Ministry of Education, there are 97,220 students enrolled on the special education programme.

#### *Children with Learning Disabilities in Malaysia DOI: http://dx.doi.org/10.5772/intechopen.113230*

As described above, learning disabilities may be manifested differently in children and are usually detected or become apparent when they start formal education. If left unattended, issues related to learning disabilities can have negative effects, among others, on the children's self-esteem and motivation to learn. Numerous studies have found a sizeable percentage of delinquents, school dropouts, and those involved in drug abuse and crime have some form of learning disabilities [34]. In addition to having full rights to education, children with learning disabilities can succeed and can benefit the most from their education if the following challenges and issues can be attended to and resolved by the authorities.

The first unresolved issue concerns the problem of identifying and classifying those with learning disabilities. As was previously stated, there are varieties of problems that can hinder learning. Some like dyslexia, dyscalculia and dysgraphia have an impact on only certain aspects of literacy skills such as reading, calculating and writing, respectively, while others are more widespread and co-occur with other forms of pervasive developmental disorders such as ASD and ADHD. This misidentification and misclassification issues could be due to the use of the broad generic term to refer to persons with learning disabilities [3]. Currently, in Malaysia, there is still no agreement on the accurate definition to define or identify individuals with learning disabilities. Instead, a very broad and heterogeneous definition is used to describe anyone identified with problems in learning. There are also no standardized criteria to identify those with learning disabilities. While efforts have been taken to provide special education schools for those with learning disabilities, these special schools accommodate students not only those with learning disabilities but also those with Down Syndrome, ASD, ADHD, Dyslexia, Slow Learner and Mental Retarded [33]. This means those who are identified with various sorts of learning problems are lumped into one category. As such, their unique learning characteristics and differences are mixed up or are not attended to and ignored. This inaccurate identification and misclassification of individuals with learning disabilities implies that ensuring adequate support and services to suit each sub-group within the current broadly defined learning disabilities is impossible. This is something that needs to be rectified because every child with a learning disability might have different needs and require specific attention.

It is, therefore, crucial to accurately understand and describe the likely character, behavior and cognitive ability of children with different forms of learning disabilities. The different behavioral and psychological manifestations of learning disabilities in children warrant for a development of a comprehensive profile in which the most important characteristics and psychological patterns of children with learning disabilities can be identified and compiled. As typically learning disabilities are closely associated with cognitive deficits, comprehensive cognitive profiling is highly recommended to be developed to help with the understanding of the children's needs in learning and subsequently mitigate their negative effects as these children are indeed capable of learning. All these should start by having a standardized and accurate definition of learning disabilities to ensure adequate assessment, intervention and research on the problems and needs of this group is available.

The second pertinent issue is the need for accurate diagnosis of children with learning disabilities. Currently, in Malaysia, there is a lack of standardized assessment tools that are locally and culturally sensitive to detect and diagnose individuals at risk for learning disabilities [18]. Research emphasizes the need for effective screening and diagnostic systems to identify developmental disorders at the earliest possible stage, clearly indicating that the chances of overcoming difficulties are significantly

enhanced by early identification [1]. The use of standardized tools to identify any potential developmental and learning problems at the early stage of the developmental phase is highly recommended because it could provide adequate and appropriate intervention to minimize the disability. Equally important is the awareness of the parents or caretakers on the importance of assessing their child following any potential symptoms for learning disabilities. A better analysis of the needs of children with learning disabilities that will allow for effective policy formulation and programme implementation must be established as currently, in Malaysia, there is a scarcity of valid and reliable data employing psychological assessment instruments to identify and characterize several neurodevelopmental disorders that hinder children from their full potential of learning.

Given that learning disabilities usually involve more than a single disorder, it also becomes essential to develop a psychological profile of Malaysian children with learning disabilities that will become the foundation on which to plan for educational support for the different kinds of learning disabilities. Over the years, there have been calls to establish a comprehensive profile to provide relevant authorities and policymakers, teachers, as well as parents, with specific information that can be used to develop a framework for personalized learning experiences to suit children's disabilities. Specifically, as much of learning disability problems are related to their cognitive functioning, a cognitive profile of children with learning disabilities must be developed. It is through this profile that the strengths as well as limitations related to their learning abilities can be identified. Based on the strengths and limitations found, a differentiated learning framework can be implemented to suit the learning needs of the children with learning disabilities. Given the dearth of research in this area in the Malaysian context and the paucity of data on learning difficulties, there is an urgent need for research to develop a cognitive profile for Malaysian children with learning disabilities in their preschool years, to allow for every child to have a programme tailored to his unique profile.

Early identification and intervention are vital to lessen the learning difficulties experienced by children with learning disabilities. They might learn differently from their normal counterparts and are capable of succeeding and can benefit the most from their education if their latent learning attributes are made explicit. As symptoms for learning disabilities become apparent early in the developmental period, assessment and identification should start early, preferably at preschool entrance stage as understanding the need and strategies for intervention must be given as soon as the disability becomes apparent, whether in kindergarten or elementary schools. Research has strongly supported the fact that early detection and intervention offer better longterm outcomes. Early identification of children who may be at risk of having specific learning disabilities is crucial to assist them in overcoming barriers to learning. As a consequence, this will help to prevent the growth of children with academic failure, lower motivation, greater frustration, distress, school dropout and peer rejection [34].

Lastly, there is a need for professional development of teachers and educators in Malaysia to understand better and address the needs of children with learning disabilities. More research on this area is needed, and parental awareness and involvement are also expected to create a more inclusive learning environment for these children. Parents are encouraged to actively participate in their child's education. They can work with teachers and educational specialists to develop strategies and plans to support their child's learning needs. Other relevant professionals such as child psychiatrists, pediatricians, child neurologists, clinical psychologists, educational psychologists and cognitive psychologists who are

necessary for the identification, assessment, evaluation and development of intervention of children with learning disabilities should also be increased as to date, in Malaysia, their number is still limited [3].


**6. Protection from and screening for radiation contamination**

The general principles of protection from radiation injury depend upon four factors: distance, time, shielding, and removal or containment of contamination [27]. When caring for potential radiation contaminated patients, healthcare personnel must minimize the duration of exposure to a source, maximize the distance from source, and establish effective shielding from the source. Identification of the presence of radioactive contamination on or within a patient mandates early removal/containment in order to forestall further damage and contamination [27]. In cases similar to the Goiania incident, hand-held Geiger counters must be utilized in order to focus on accurately identifying anatomic areas of contamination unique to each individual [1]. Substantial exposure of emergency responders and clinicians caring for potentially heavily contaminated patients may occur. Emergency medical services and clinicians must use caution and adhere to strict precautions for managing hazardous materials to prevent inadvertent contamination of themselves and others [27]. Personnel should wear radiation dosimeters, sealed in clear, airtight plastic bags, and worn outside the clothing to allow rapid assessment and early detection of contamination. Workers and work areas should undergo repeated surveillance with radiation detectors at appropriate intervals [1, 27].

to the face or abdomen, or other factors [27]. In addition, the presence of nausea and vomiting within several (usually around 4) hours of exposure may also be diagnostically helpful.

Fundamentals of Medical Radiation Safety: Focus on Reducing Short-Term and Long-Term…

http://dx.doi.org/10.5772/intechopen.85689

65

Similar to other toxicological phenomena, determining the potential harm of radiation exposure mandates consideration of three factors: dose of radiation exposure, tissue or surface area exposed, and duration of exposure. Whole body radiation exposure to 4 or 5 Sv (or Gy) imparts potentially lethal effects, while an extremity can tolerate several times that exposure [27]. General measures of radiation exposure (e.g., fluoroscopy time) have low utility and accuracy [28]. At this juncture, it is important to introduce the concept of KERMA, or "Kinetic Energy Released in Matter", which is a measure of energy delivered (or dose) [28]. Air-KERMA is the KERMA measured in air (e.g., low scatter environment) [28]. More useful methods of determining radiation administered include: (a) total air-KERMA (exposure) at pre-specified reference point, (b) air-KERMA area product, and (c) peak skin dose or the maximum dose received by any local area of patient skin [28, 59]. See **Figures 3–5** for further information.

**8. Measuring severity of radiation dose**

**Figure 3.** Timeline for post exposure injury for dosage of 2–5 Gy.

**Figure 4.** Timeline for post exposure injury for dosage of 10–15 Gy.

**Figure 5.** Timeline for post exposure injury for dosage >15 Gy.

#### **7. Laboratory evaluation of acute radiation injury**

In cases of more significant exposure, ARaS manifests initially through the hematopoietic system as blood marrow tissues are highly radiosensitive [27]. Of all the components of hematopoiesis, circulating lymphocytes have the most radiosensitive cell lines and provides a useful laboratory tool to screen for the severity of the radiation sickness early in observation (**Figure 2**) [56]. After whole body exposure above 0.5 Gy, the rapid fall in lymphocyte number starts within hours, and the lymphocyte depletion is proportional to the dose between 1 and 10 Gy [56]. GM-CSF may be helpful for the recovery of the bone marrow function after clinically significant radiation exposure [57]. Lymphocyte depletion kinetics serves as the single best estimator of radiation exposure and clinical outcome [27]. A decrease in absolute lymphocyte levels may be observed at whole-body doses as low as 100 mSv, but clinically significant response may not be seen below 1–2 Sv. Depending on the absorbed dose, such changes can begin within hours of exposure, so it is recommended that an immediate complete blood count with differential is performed as a baseline and then every 6–12 hours thereafter for 2–3 days [27]. An elevated serum amylase provides a supplementary piece of information that may also be an early sign of serious radiation exposure involving the head and neck. The results of this test are nonspecific; however, and they may also reflect alcohol intake, a stress response, trauma

**Figure 2.** Time-dependent lymphocyte depletion kinetics following either severe or moderate radiation exposures. As early as 6–12 hours following exposure, there may be some indication of the severity of the exposure [35].

to the face or abdomen, or other factors [27]. In addition, the presence of nausea and vomiting within several (usually around 4) hours of exposure may also be diagnostically helpful.


*Review* **Sustainability of Heating, Ventilation and Air-Conditioning (HVAC) Systems in Buildings—An Overview**

**Nilofar Asim 1,\*, Marzieh Badiei 2, Masita Mohammad 1, Halim Razali 1, Armin Rajabi 3, Lim Chin Haw 1 and Mariyam Jameelah Ghazali 3,\***

**Abstract:** Increasing demand on heating, ventilation, and air-conditioning (HVAC) systems and their importance, as the respiratory system of buildings, in developing and spreading various microbial contaminations and diseases with their huge global energy consumption share have forced researchers, industries, and policymakers to focus on improving the sustainability of HVAC systems. Understanding and considering various parameters related to the sustainability of new and existing HVAC systems as the respiratory system of buildings are vital to providing healthy, energyefficient, and economical options for various building types. However, the greatest opportunities for improving the sustainability of HVAC systems exist at the design stage of new facilities and the retrofitting of existing equipment. Considering the high available percentage of existing HVAC systems globally reveals the importance of their retrofitting. The attempt has been made to gather all important parameters that affect decision-making to select the optimum HVAC system development considerations among the various opportunities that are available for sustainability improvement.

**Keywords:** HVAC systems; sustainability; energy efficient; indoor air quality; water recovery; retrofitting


*7.2.2 Speech recognition*

can be treated as a statistic criterion approach which is discussed in Section 4.2. In the paper of demystifying neural style transfer [40], the authors show that matching Gram matrices (i.e., style loss) is equivalent to minimize the MMD (i.e., Eq. 4). Based on this argument, they introduce several style transfer methods by utilizing different types of kernel functions in the MMD and achieve impressive

An interesting but challenging task is to utilize deep neural networks to describe an input image with natural language, which is well known as the image caption. Specifically, the goal of image caption is to learn a mapping function *Ft*, so that we can get *Ft*ð Þ! *Image Text* and vice versa. Note that there are two different data space involved in this task: a dataset with images vs. a dataset with text. Therefore, based on the categorization methods which are discussed in Section 3.3, image caption belongs to heterogeneous domain adaptation. A general method to implement this idea is to utilize a CNN-RNN architecture (i.e., recurrent neural network), where the CNN is used for encoding an input image to some hidden

representation and the RNN can decode the representation to some sentences which can describe the content of this image. In particular, the CNN is usually pre-trained

When we apply an image-caption model which is trained from image dataset A on image dataset B, the performance will degrade due to the distribution change or domain shift of two datasets. To address this problem, the work in [42] introduces an adversarial learning method to address unpaired data in the target domain for image caption (i.e., adversarial domain adaptation approach in Section 5). In [43], the authors propose a dual learning method for addressing this problem, which involves two steps: (1) A CNN-RNN model is trained with sufficient labeled data in the source domain. (2) The model is then fine-tuned with limited target data. The core idea of dual learning mechanism involved a reverse mapping process: the model firstly maps an input target image to text (i.e., *CNN* � *RNN Image* ð Þ! *Text*) and the text is then mapped back to an image by a generator network, which is further distinguished by a discriminator network. Therefore, the work in [43]

Deep domain adaptation technique is also used for solving a variety of tasks in

processing natural language. In [44], an effective domain mixing method for machine translation is introduced. The core idea is to jointly train domain discrimination and translation networks. The authors in [45] propose aspect-augmented adversarial networks for text classification. The main idea is to adopt a domain classifier, which has been discussed in Section 5.2. Recently, an interesting research area is to utilize neural models to automatically generate answers based on the input questions, which is also known as questions answering. However, the main challenge to train models is that it is usually difficult to collect a large dataset of labeled question-answer pairs. Therefore, domain adaptation is a natural choice to address this problem. E.g., in [46], a framework called generative domain-adaptive nets is introduced. Specifically, a generative model is used to generate questions from the unlabeled text for enhancing the model performance. Other applications of domain

based on the ImageNet and then we can re-train it in the CNN-RNN [41].

belongs to sample-reconstruction approach (i.e., in Section 6).

**7.2 Applications beyond computer vision**

*7.2.1 Natural language processing*

**56**

results.

*7.1.5 Image caption*

*Advances and Applications in Deep Learning*

A typical real-world application is to transcribe speech into text, which is also known as automatic speech recognition. Domain adaptation is also suitable for addressing the training-testing mismatch of speech recognition that is caused by the shift of data distribution between different datasets. For example, a neural model trained on a manually collected dataset may generalize poorly in the real-world application of speech recognition due to the environmental noises. In [48], an adaptive teacher-student learning method is proposed for domain adaptation in speech recognition systems. In [49], the domain classifier that is discussed above is also adopted for robust speech recognition. Similar work can also be found in [50], in which the adversarial learning method for domain adaptation is also used for addressing the unseen recoding conditions.