**Abstract**

Numerous methods exist aimed at examining patterns in structured and unstructured financial data. Applications of these methods include fraud detection, risk management, credit allocation, assessment of the risk of default, customer analytics, trading prediction, and many others, creating a broad field of research named Financial data science. A problem within the field that remains significantly underresearched, yet very important, is that of differentiating between the three major types of business activities—merchandising, manufacturing, and service based on the structured data available in financial reports. It can be argued that, due to the inherent idiosyncrasies of the three types of business activities, methods for assessment of the risk of default, methods for credit allocation, and methods for fraud detection would all see an improved performance if reliable information on the percentage of entities' business activities allocated to the three major activities would be available. To this end, in this paper, we propose a clustering procedure that relies on Principal Component Analysis (PCA) for dimensionality reduction and feature selection. The procedure is presented using a large empirical data set comprising complete financial reports for various business entities operating in the Republic in Serbia, that pertain to the reporting period 2019.

**Keywords:** data science, principal component analysis, random forest algorithm, financial data, financial reporting


*Edited by Alok Raghav and Jamal Ahmad*

The diverse phenomenon of post-translational modifications of biological macromolecules (proteins, lipids, and nucleic acids) includes phosphorylation, glycosylation, ubiquitination, nitrosylation, methylation, acetylation, lipidation, and proteolysis. The mechanism of protein glycosylation has an important role in the regulation of human health. This book identifies the fundamentals of glycosylation that help in understanding the concepts of protein glycosylation and its significance.

Published in London, UK © 2022 IntechOpen © Fahroni / iStock

Fundamentals of Glycosylation

Fundamentals of

Glycosylation

*Edited by Alok Raghav and Jamal Ahmad*


**2. What is stress and what are the physiological responses to stress?**

For a term used frequently in everyday language, stress has proven surprisingly difficult to define. Stress is a term that can appear diffuse, lacking in rigor and certainty of meaning. Nevertheless, most published definitions of stress are concerned with challenges to, or disruptions of, homeostasis. Indeed, our own working definition of stress is "a complex physiological state that embodies a range of integrative physiological and behavioral processes that occur when there is a real or perceived threat to homeostasis" [1, 2]. Certainly, the importance of the maintenance of homeostasis has long been recognized. For example, the ancient Greek philosopher Empedocles (500-430 BC) acknowledged the

Sex Differences and the Role of Sex Steroids in Sympatho-Adrenal

Medullary System and Hypothalamo-Pituitary Adrenal Axis Responses to Stress 117

Fig. 1. Schematic diagram of the sympatho-adrenal medullary system, hypothalamo-pituitary adrenal axis and some opioidergic pathways. The sympatho-adrenal medullary system consists of the sympathetic nervous system and adrenal medulla. Pre-ganglionic neurons

concept of a steady or harmonious state [3] and, in the 19th century, the work of French physiologist Claude Bernard (1813-1878) laid the groundwork for appreciating the importance of adaptive internal mechanisms to challenges [3]. Bernard developed the concept that organisms maintain a stable internal environment (*milieu intérieur*). This concept and understanding was substantially extended by the groundbreaking research of American physiologist Walter Cannon (1871-1945) [3]. It was Cannon who devised the term "homeostasis" and who noted that animals and humans in dangerous situations showed adaptive responses in which they may choose to fight or to escape, termed the "fight or flight" syndrome [4]. Clearly, this requires rapid responses of the body and the physiological system primarily responsible for these adaptive responses is the sympathoadrenal medullary system. The work of Cannon inspired another researcher, Hans Selye (1907 Vienna-1982, Montreal), whose seminal work during the 1930's at McGill University in Montreal, Canada, led to the development of a theory to describe the concept of stress. He developed the "General Adaptation Syndrome", defined as "the sum of all non-specific, systemic reactions of the body which ensue upon long continued exposure to stress" [5]. He depicted three stages in this response: 1) the alarm reaction, which involved activation of the hypothalamo-pituitary adrenal axis, 2) the period of resistance, where the organism "coped" with the challenge and 3) the stage of exhaustion, where the organism's ability to resist or adapt to the challenge declined [5]. A premise of this theory is that organisms have a generalized and non-specific response to all noxious stimuli [5]. While it is now recognized that there may be different types of physiological responses to different stressful environments [1], Selye unquestionably founded the field of stress physiology and provided the framework to define and understand stress. His work continues to stimulate debate and research. Importantly, his work demonstrated the paramount role of the hypothalamopituitary adrenal axis in adaption to stressful situations [5].

It follows from the work of Cannon and Selye that the two most common physiological responses to stress are activation of the sympatho-adrenal medullary system and the hypothalamo-pituitary adrenal axis (Figure 1). The former is activated immediately upon threat or detection of a noxious stimulus and the response is transient, whereas the latter is activated less rapidly and the response is more prolonged. It is common practice to define threats and noxious stimuli that cause stress responses as stressors [1, 2]. While the sympatho-adrenal medullary system and hypothalamo-pituitary adrenal axis are considered the primary means of dealing with stressors, there are other responses, mostly of a neural and neuroendocrine nature, such as the opioidergic system [2], which contribute to an integrated stress response.

The sympatho-adrenal medullary system consists of the sympathetic nervous system and the adrenal medulla (Figure 1). The catecholamines epinephrine and norepinephrine induce the actions of the sympatho-adrenal medullary system which are primarily to stimulate rapid and vigorous neural, behavioral and muscular activity, to stimulate the cardiovascular system to increase cardiac output and redistribute blood flow to the pulmonary blood system and appropriate organs to deal with the stressor [6]. The catecholamines bind to adrenergic receptors, of which there are different subtypes, termed α and β, and this allows for divergent effects in target tissues [6]. The sympathetic component, or "arm", of the sympatho-adrenal medullary system, comprises pre-ganglionic neurons that project from the spinal cord to the various ganglia in the body where they synapse with post-ganglionic neurons that project to, and innervate, target tissues. Acetylcholine from the pre-ganglionic neurons stimulates the post-ganglionic neurons which release norepinephrine into the target tissue. In the adrenal arm of the sympatho-adrenal medullary system, pre-ganglionic

concept of a steady or harmonious state [3] and, in the 19th century, the work of French physiologist Claude Bernard (1813-1878) laid the groundwork for appreciating the importance of adaptive internal mechanisms to challenges [3]. Bernard developed the concept that organisms maintain a stable internal environment (*milieu intérieur*). This concept and understanding was substantially extended by the groundbreaking research of American physiologist Walter Cannon (1871-1945) [3]. It was Cannon who devised the term "homeostasis" and who noted that animals and humans in dangerous situations showed adaptive responses in which they may choose to fight or to escape, termed the "fight or flight" syndrome [4]. Clearly, this requires rapid responses of the body and the physiological system primarily responsible for these adaptive responses is the sympathoadrenal medullary system. The work of Cannon inspired another researcher, Hans Selye (1907 Vienna-1982, Montreal), whose seminal work during the 1930's at McGill University in Montreal, Canada, led to the development of a theory to describe the concept of stress. He developed the "General Adaptation Syndrome", defined as "the sum of all non-specific, systemic reactions of the body which ensue upon long continued exposure to stress" [5]. He depicted three stages in this response: 1) the alarm reaction, which involved activation of the hypothalamo-pituitary adrenal axis, 2) the period of resistance, where the organism "coped" with the challenge and 3) the stage of exhaustion, where the organism's ability to resist or adapt to the challenge declined [5]. A premise of this theory is that organisms have a generalized and non-specific response to all noxious stimuli [5]. While it is now recognized that there may be different types of physiological responses to different stressful environments [1], Selye unquestionably founded the field of stress physiology and provided the framework to define and understand stress. His work continues to stimulate debate and research. Importantly, his work demonstrated the paramount role of the hypothalamo-

It follows from the work of Cannon and Selye that the two most common physiological responses to stress are activation of the sympatho-adrenal medullary system and the hypothalamo-pituitary adrenal axis (Figure 1). The former is activated immediately upon threat or detection of a noxious stimulus and the response is transient, whereas the latter is activated less rapidly and the response is more prolonged. It is common practice to define threats and noxious stimuli that cause stress responses as stressors [1, 2]. While the sympatho-adrenal medullary system and hypothalamo-pituitary adrenal axis are considered the primary means of dealing with stressors, there are other responses, mostly of a neural and neuroendocrine nature, such as the opioidergic system [2], which contribute to

The sympatho-adrenal medullary system consists of the sympathetic nervous system and the adrenal medulla (Figure 1). The catecholamines epinephrine and norepinephrine induce the actions of the sympatho-adrenal medullary system which are primarily to stimulate rapid and vigorous neural, behavioral and muscular activity, to stimulate the cardiovascular system to increase cardiac output and redistribute blood flow to the pulmonary blood system and appropriate organs to deal with the stressor [6]. The catecholamines bind to adrenergic receptors, of which there are different subtypes, termed α and β, and this allows for divergent effects in target tissues [6]. The sympathetic component, or "arm", of the sympatho-adrenal medullary system, comprises pre-ganglionic neurons that project from the spinal cord to the various ganglia in the body where they synapse with post-ganglionic neurons that project to, and innervate, target tissues. Acetylcholine from the pre-ganglionic neurons stimulates the post-ganglionic neurons which release norepinephrine into the target tissue. In the adrenal arm of the sympatho-adrenal medullary system, pre-ganglionic

pituitary adrenal axis in adaption to stressful situations [5].

an integrated stress response.

Fig. 1. Schematic diagram of the sympatho-adrenal medullary system, hypothalamo-pituitary adrenal axis and some opioidergic pathways. The sympatho-adrenal medullary system consists of the sympathetic nervous system and adrenal medulla. Pre-ganglionic neurons

Sex Differences and the Role of Sex Steroids in Sympatho-Adrenal

with the objective of re-establishing homeostasis [17-24].

to stress responses are unknown [1].

Medullary System and Hypothalamo-Pituitary Adrenal Axis Responses to Stress 119

evident as widespread effects to mobilize energy stores throughout the body [17-24]. Furthermore, these hormones have far reaching effects on most tissues, organs and systems

The hypothalamo-pituitary adrenal axis is regulated by various neural inputs and negative feedback by the glucocorticoids. There are extensive neuronal pathways within the central nervous system that are activated during stress and there are multiple interactions between these systems (for review see [1]). For example, there are reciprocal connections between noradrenergic neurons located in the brain stem (A1, A2 and A6 noradrenergic cell groups) and CRH and AVP neurons in the paraventricular nuclei of the hypothalamus that are important in mounting a stress response [1]. There are also reciprocal interactions between CRH and AVP neurons and cells in the arcuate nucleus, particularly those expressing peptides derived from POMC, including β-endorphin [1]. It has been shown in rats that serotonergic neurons project from the raphe nucleus of the midbrain to the hypothalamus, and there are interactions between serotoninergic cells, the hypothalamo-pituitary adrenal axis and the sympathetic nervous system [1]. There are also neurons that produce the opioid peptide enkephalin in the paraventricular nucleus but the significance of these with respect

The negative feedback effects of glucocorticoids on the brain are mediated via high affinity mineralocorticoid receptors (MR) and low affinity glucocorticoid receptors (GR). MR are present in the hippocampus and other regions of the limbic system, including the amygdala and lateral septum, and in the hypothalamus [1, 2]. Glucocorticoids act via MR to maintain the basal activity of the hypothalamo-pituitary adrenal axis [25, 26]. The distribution of GR within the brain is much more widespread than for MR and they are found extensively within the hypothalamus and also the anterior pituitary gland [27]. GR are involved in the negative feedback actions of both basal and stress-induced levels of glucocorticoids, particularly the latter and facilitate homeostasis when stress levels of glucocorticoids prevail [25, 26, 28]. The hypothalamo-pituitary adrenal undergoes a circadian rhythm of regulation

While the sympatho-adrenal medullary system and the hypothalamo-pituitary adrenal axis are acknowledged as the front-line physiological systems to deal with stress, the opioids (Figure 1) also have a diverse range of stress-related actions [2]. There are three classes of opioids: β-endorphin, the enkephalins (met-enkephalin and leu-enkephalin) and dynorphin. The opioids act via different receptor subtypes (termed μ, δ and κ) and β-endorphin is the opioid most studied in terms of responses to stress (for review see [2]). As indicated above, β-endorphin is involved in the regulation of the hypothalamo-pituitary adrenal axis and the opioids are generally considered to attenuate and terminate stress responses [2]. Furthermore, these neuropeptides regulate sympathetic, cardiovascular and neural control systems and are involved in the regulation of pain, reinforcement and reward, the release of

Although the opioids clearly play various roles in responses to stress, and in regulating hypothalamo-pituitary adrenal axis responses to stress, it remains the case that most research on stress, particularly with respect to responses to, and impact of, different stressors has been on the sympatho-adrenal medullary system and the hypothalamopituitary adrenal axis. Consequently, we focus on these systems here, while acknowledging the need for a greater understanding of the roles of the opioidergic and other central

systems in stress responses, and in the impact of stress on physiology and behaviour.

and this is evident in the negative feedback actions of the glucocorticoids [17-24].

neurotransmitters and other autonomic and neuroendocrine functions [2].

extend from the spinal cord to ganglia and to the adrenal medulla. When activated the preganglionic neurons release the neurotransmitter acetylcholine (Ach) that stimulates postganglionic neurons to release norepinephrine (NE) directly into target tissue and endocrine cells called chromaffin cells in the adrenal medulla to release epinephrine (E) and NE into the peripheral blood system. The hypothalamo-pituitary adrenal axis is regulated by corticotropin releasing hormone (CRH) and arginine vasopressin (AVP) in the paraventricular nucleus (PVN) of the hypothalamus which are released into the hypophyseal portal blood system and transported to the anterior pituitary. They stimulate the synthesis of pro-opiomelanocortin (POMC) resulting in various products including adrenocorticotropic hormone (ACTH) and the opioid β-endorphin, which are secreted into the peripheral blood system. ACTH acts at the adrenal cortex to stimulate synthesis of the glucocorticoids which are cortisol in humans and non-rodent species (shown here) and corticosterone in rodents and avian species. β-endorphin is also synthesized in the arcuate nucleus (ARC) and the opioid met-enkephalin (Met-enk) in the adrenal medulla in response to stress.

neurons innervate endocrine cells, called chromaffin cells, in the adrenal medulla, stimulating them to synthesize epinephrine and norepinephrine, and to secrete both catecholamines into the systemic circulation. These catecholamines then act as classic hormones, affecting target tissues throughout the body. It is generally considered that more epinephrine than norepinephrine is released from the adrenal medulla into the systemic circulation [7] because norepinephrine is converted to epinephrine [6]. While this may be the case in various species, possibly including humans, in sheep the adrenal medulla secretes substantially more norepinephrine than epinephrine [8].

The hypothalamo-pituitary adrenal axis is often referred to as the "Stress System" and one might imagine that this is a result of the work of Selye that effectively identified the importance of the adrenal glands in coping with stress. This is a classic neuroendocrine axis where the hypothalamus of the brain controls the activity of the adrenal glands via the anterior pituitary gland (Figure 1). The adrenals are located in the visceral cavity superior to the kidneys. Neurons in each paraventricular nucleus of the hypothalamus synthesize the neuropeptides that are released when stressors activate the hypothalamo-pituitary adrenal axis. These are referred to as hypophysiotropic hormones [9] and in the case of the hypothalamo-pituitary adrenal axis are corticotropic releasing hormone (CRH) [10] and, in all species studied except the pig, arginine vasopressin (AVP) [11]. In the pig, lysine substitutes for arginine to form lysine vasopressin [2]. CRH and AVP are secreted from the terminals of neurons directly into the primary capillary bed of a specialized portal blood system that communicates between the hypothalamus and anterior pituitary gland. This is the hypophyseal portal blood system [9]. CRH and AVP are transported by portal vessels to the secondary capillary bed where they exit and act upon corticotropes, the endocrine cells that produce peptides derived from pro-opiomelanocortin (POMC). These include adrenocorticotropic hormone (ACTH), the opioid β-endorphin and α-melanocyte stimulating hormone [12-16]. Of these, ACTH is of major importance when it comes to regulation of the hypothalamo-pituitary adrenal axis. ACTH acts on the cortex of the adrenal glands to stimulate the synthesis of steroids, including the glucocorticoids, which are essential in responding to stress. In many species, including humans, the predominant glucocorticoid released from the adrenal glands is cortisol. In rodents and avian species it is corticosterone [1]. As the name suggests, glucocorticoids have glucoregulatory actions,

neurons innervate endocrine cells, called chromaffin cells, in the adrenal medulla, stimulating them to synthesize epinephrine and norepinephrine, and to secrete both catecholamines into the systemic circulation. These catecholamines then act as classic hormones, affecting target tissues throughout the body. It is generally considered that more epinephrine than norepinephrine is released from the adrenal medulla into the systemic circulation [7] because norepinephrine is converted to epinephrine [6]. While this may be the case in various species, possibly including humans, in sheep the adrenal medulla secretes

The hypothalamo-pituitary adrenal axis is often referred to as the "Stress System" and one might imagine that this is a result of the work of Selye that effectively identified the importance of the adrenal glands in coping with stress. This is a classic neuroendocrine axis where the hypothalamus of the brain controls the activity of the adrenal glands via the anterior pituitary gland (Figure 1). The adrenals are located in the visceral cavity superior to the kidneys. Neurons in each paraventricular nucleus of the hypothalamus synthesize the neuropeptides that are released when stressors activate the hypothalamo-pituitary adrenal axis. These are referred to as hypophysiotropic hormones [9] and in the case of the hypothalamo-pituitary adrenal axis are corticotropic releasing hormone (CRH) [10] and, in all species studied except the pig, arginine vasopressin (AVP) [11]. In the pig, lysine substitutes for arginine to form lysine vasopressin [2]. CRH and AVP are secreted from the terminals of neurons directly into the primary capillary bed of a specialized portal blood system that communicates between the hypothalamus and anterior pituitary gland. This is the hypophyseal portal blood system [9]. CRH and AVP are transported by portal vessels to the secondary capillary bed where they exit and act upon corticotropes, the endocrine cells that produce peptides derived from pro-opiomelanocortin (POMC). These include adrenocorticotropic hormone (ACTH), the opioid β-endorphin and α-melanocyte stimulating hormone [12-16]. Of these, ACTH is of major importance when it comes to regulation of the hypothalamo-pituitary adrenal axis. ACTH acts on the cortex of the adrenal glands to stimulate the synthesis of steroids, including the glucocorticoids, which are essential in responding to stress. In many species, including humans, the predominant glucocorticoid released from the adrenal glands is cortisol. In rodents and avian species it is corticosterone [1]. As the name suggests, glucocorticoids have glucoregulatory actions,

extend from the spinal cord to ganglia and to the adrenal medulla. When activated the preganglionic neurons release the neurotransmitter acetylcholine (Ach) that stimulates postganglionic neurons to release norepinephrine (NE) directly into target tissue and endocrine cells called chromaffin cells in the adrenal medulla to release epinephrine (E) and NE into the peripheral blood system. The hypothalamo-pituitary adrenal axis is regulated by corticotropin releasing hormone (CRH) and arginine vasopressin (AVP) in the paraventricular nucleus (PVN) of the hypothalamus which are released into the hypophyseal portal blood system and transported to the anterior pituitary. They stimulate the synthesis of pro-opiomelanocortin (POMC) resulting in various products including adrenocorticotropic hormone (ACTH) and the opioid β-endorphin, which are secreted into the peripheral blood system. ACTH acts at the adrenal cortex to stimulate synthesis of the glucocorticoids which are cortisol in humans and non-rodent species (shown here) and corticosterone in rodents and avian species. β-endorphin is also synthesized in the arcuate nucleus (ARC) and the opioid met-enkephalin (Met-enk) in

the adrenal medulla in response to stress.

substantially more norepinephrine than epinephrine [8].

evident as widespread effects to mobilize energy stores throughout the body [17-24]. Furthermore, these hormones have far reaching effects on most tissues, organs and systems with the objective of re-establishing homeostasis [17-24].

The hypothalamo-pituitary adrenal axis is regulated by various neural inputs and negative feedback by the glucocorticoids. There are extensive neuronal pathways within the central nervous system that are activated during stress and there are multiple interactions between these systems (for review see [1]). For example, there are reciprocal connections between noradrenergic neurons located in the brain stem (A1, A2 and A6 noradrenergic cell groups) and CRH and AVP neurons in the paraventricular nuclei of the hypothalamus that are important in mounting a stress response [1]. There are also reciprocal interactions between CRH and AVP neurons and cells in the arcuate nucleus, particularly those expressing peptides derived from POMC, including β-endorphin [1]. It has been shown in rats that serotonergic neurons project from the raphe nucleus of the midbrain to the hypothalamus, and there are interactions between serotoninergic cells, the hypothalamo-pituitary adrenal axis and the sympathetic nervous system [1]. There are also neurons that produce the opioid peptide enkephalin in the paraventricular nucleus but the significance of these with respect to stress responses are unknown [1].

The negative feedback effects of glucocorticoids on the brain are mediated via high affinity mineralocorticoid receptors (MR) and low affinity glucocorticoid receptors (GR). MR are present in the hippocampus and other regions of the limbic system, including the amygdala and lateral septum, and in the hypothalamus [1, 2]. Glucocorticoids act via MR to maintain the basal activity of the hypothalamo-pituitary adrenal axis [25, 26]. The distribution of GR within the brain is much more widespread than for MR and they are found extensively within the hypothalamus and also the anterior pituitary gland [27]. GR are involved in the negative feedback actions of both basal and stress-induced levels of glucocorticoids, particularly the latter and facilitate homeostasis when stress levels of glucocorticoids prevail [25, 26, 28]. The hypothalamo-pituitary adrenal undergoes a circadian rhythm of regulation and this is evident in the negative feedback actions of the glucocorticoids [17-24].

While the sympatho-adrenal medullary system and the hypothalamo-pituitary adrenal axis are acknowledged as the front-line physiological systems to deal with stress, the opioids (Figure 1) also have a diverse range of stress-related actions [2]. There are three classes of opioids: β-endorphin, the enkephalins (met-enkephalin and leu-enkephalin) and dynorphin. The opioids act via different receptor subtypes (termed μ, δ and κ) and β-endorphin is the opioid most studied in terms of responses to stress (for review see [2]). As indicated above, β-endorphin is involved in the regulation of the hypothalamo-pituitary adrenal axis and the opioids are generally considered to attenuate and terminate stress responses [2]. Furthermore, these neuropeptides regulate sympathetic, cardiovascular and neural control systems and are involved in the regulation of pain, reinforcement and reward, the release of neurotransmitters and other autonomic and neuroendocrine functions [2].

Although the opioids clearly play various roles in responses to stress, and in regulating hypothalamo-pituitary adrenal axis responses to stress, it remains the case that most research on stress, particularly with respect to responses to, and impact of, different stressors has been on the sympatho-adrenal medullary system and the hypothalamopituitary adrenal axis. Consequently, we focus on these systems here, while acknowledging the need for a greater understanding of the roles of the opioidergic and other central systems in stress responses, and in the impact of stress on physiology and behaviour.

Sex Differences and the Role of Sex Steroids in Sympatho-Adrenal

require some higher cortical processing involving limbic pathways [50].

impact on normal physiological functioning [19, 20, 32].

**5. Sex differences in responses to stress**

response to stress.

medullary system and the hypothalamo-pituitary adrenal axis.

Medullary System and Hypothalamo-Pituitary Adrenal Axis Responses to Stress 121

are perceived to pose a threat to homeostasis and which result in "anticipatory" glucocorticoid responses to stress. Herman and colleagues [50] asserted that "reactive" glucocorticoid responses to stress are those induced by a genuine challenge to physiological homeostasis that is recognized by sensory pathways. Such challenges may include a change in cardiovascular tone, respiratory distress, pain or circulating cytokines. In such cases, there is a direct neuronal pathway to CRH neurons in the paraventricular nucleus via the brain stem to activate the hypothalamo-pituitary adrenal axis. In contrast, "anticipatory" glucocorticoid responses to stress are not mounted in response to an actual disruption to physiological homeostasis but to the anticipation of such a disruption. These responses

Physiological responses to physical stressors may be considered appropriate since the body is being prepared for a real threat and the elevated heart rate and blood pressure and energy stores mobilised by catecholamines and glucocorticoids (see Section 2) are required to deal with the stressor. For example, a direct physical threat may require vigorous skeletal muscle activity in order to avert detrimental consequences imposed by the stressor. Conversely, physiological responses to psychological stressors are potentially more harmful since the body does not usually need to respond with a physical use of energy, certainly not for a prolonged period. This would be evident where there may be a stressful environment induced without the need for physical exercise, such as being caught in traffic on the way to an important appointment. Heart rate and blood pressure may be elevated, and energy stores mobilized, but with no obvious benefit to dealing with the stressor. An exception would be the possible beneficial effects of increased mental acuity. Nevertheless, it follows that psychological stress may be detrimental to health, particularly if it is prolonged or repeated frequently, because it unnecessarily elevates heart rate and blood pressure and mobilizes energy stores placing unnecessary strain on essential physiological systems. It is important to appreciate that excessive activation of the stress systems can have a negative

Since different types of stressors activate the physiological stress systems via different mechanisms, it is important to consider different types of stressors when considering the roles of sex and the sex steroids in influencing the responsiveness of the sympatho-adrenal

Men and women differ in the prevalence of chronic diseases. For example, men have a higher risk of infectious disease [51] and incidence of cardiovascular disease than women [52, 53] whereas women have a higher incidence of major depression and anxiety [54-56] and autoimmune disorders, including rheumatoid arthritis, systemic lupus erythematosus and multiple sclerosis [57] than men. Since there are also sex differences in the response to stress, the response to stress poses a potential candidate in the etiology of the chronic disease progression. As indicated above, we will focus on the sympatho-adrenal medullary system and hypothalamo-pituitary adrenal axis when considering sex differences in

There has been relatively little research on sex differences in the response of the sympathoadrenal medullary system to stress compared to the hypothalamo-pituitary adrenal axis, where most of the effort has been concentrated. We conducted one study comparing plasma catecholamine concentrations in gonadectomized sheep subjected to isolation and restraint

## **3. Stress and health**

Irrespective of the precise definition of stress that one chooses, it is clear that stress embodies a range of physiological and behavioral processes that occur when there is a real or perceived threat to homeostasis. These adaptive responses are designed to re-establish homeostasis and allow coping. For the most part, this is what they do but if the various stress systems are repeatedly or continuously activated over long periods the effects can be deleterious for health [18, 20-24, 29-33]. This is not surprising when one considers the actions of catecholamines and glucocorticoids, as well as other stress hormones and neuropeptides like the opioids. For example, stimulation of the cardiovascular system and mobilization of energy have clear benefits in the short term in dealing with stress but the longer term effects will likely have harmful outcomes, increasing the chance of cardiovascular disease and energy deficits. This premise holds for most body systems as all tissues are affected by stress hormones. Initial benefits can become serious drawbacks, with the stress response becoming pathological.

Severe stress is associated with the increased prevalence of devastating conditions such as major depression, dementia and impaired cognition; cardiovascular disease; impaired immune function with increased vulnerability to disease; impaired growth and reproductive function; osteoporosis; diabetes, the metabolic syndrome and reduced life expectancy [18, 20-24, 29-47]. Some of the conditions associated with severe stress, such as major depression and cardiovascular disease, are amongst the most serious and costly to treat [17][48]. As with most areas of stress research, it is the hypothalamo-pituitary adrenal axis that has received most attention in terms of the impact on health. Nevertheless, as indicated, repeated and chronic activation of the sympatho-adrenal medullary system can lead to disorders and the increased prevalence of ill-health. In addition to stress, there are clinical conditions where the concentrations of glucocorticoids are pathologically high, and this is associated with physiological and behavioral dysfunction similar to that seen during chronic stress. These conditions include Cushing's Syndrome [35, 36], Cushing's Disease [35, 36] obesity [37], metabolic syndrome [37], functional hypothalamic amenorrhea [38, 39], hyperthyroidism [24], Diabetes Mellitus type II [37], hypertension [37] and major depression [37].

It follows that understanding stress responses is important if preventions and treatments of the deleterious effects of stress are to be established. This understanding will need to encompass the mechanisms of responses under a range of conditions, and in response to various stressors, as well as the effects of these responses on the body. The latter is not the focus of the current discussion but the former is. Individuals react to stressors in different ways and various physiological conditions including the sex of an individual will influence stress responses [1, 49]. Given that physiological responses to stress are important determinants for health, we will consider different types of stressors, sex differences in response to stress and the importance of physiological state, particularly reproductive state, in influencing responses to stress.

#### **4. Different types of stressors**

There are many different stressors that we encounter in our daily lives. It is commonly considered that stressors can be categorized as physical stressors or psychological stressors [1]. Physical stressors are those that pose a real threat to homeostasis and which result in "reactive" glucocorticoid responses to stress, whereas psychological stressors are those that

Irrespective of the precise definition of stress that one chooses, it is clear that stress embodies a range of physiological and behavioral processes that occur when there is a real or perceived threat to homeostasis. These adaptive responses are designed to re-establish homeostasis and allow coping. For the most part, this is what they do but if the various stress systems are repeatedly or continuously activated over long periods the effects can be deleterious for health [18, 20-24, 29-33]. This is not surprising when one considers the actions of catecholamines and glucocorticoids, as well as other stress hormones and neuropeptides like the opioids. For example, stimulation of the cardiovascular system and mobilization of energy have clear benefits in the short term in dealing with stress but the longer term effects will likely have harmful outcomes, increasing the chance of cardiovascular disease and energy deficits. This premise holds for most body systems as all tissues are affected by stress hormones. Initial benefits can become serious drawbacks, with

Severe stress is associated with the increased prevalence of devastating conditions such as major depression, dementia and impaired cognition; cardiovascular disease; impaired immune function with increased vulnerability to disease; impaired growth and reproductive function; osteoporosis; diabetes, the metabolic syndrome and reduced life expectancy [18, 20-24, 29-47]. Some of the conditions associated with severe stress, such as major depression and cardiovascular disease, are amongst the most serious and costly to treat [17][48]. As with most areas of stress research, it is the hypothalamo-pituitary adrenal axis that has received most attention in terms of the impact on health. Nevertheless, as indicated, repeated and chronic activation of the sympatho-adrenal medullary system can lead to disorders and the increased prevalence of ill-health. In addition to stress, there are clinical conditions where the concentrations of glucocorticoids are pathologically high, and this is associated with physiological and behavioral dysfunction similar to that seen during chronic stress. These conditions include Cushing's Syndrome [35, 36], Cushing's Disease [35, 36] obesity [37], metabolic syndrome [37], functional hypothalamic amenorrhea [38, 39], hyperthyroidism [24],

It follows that understanding stress responses is important if preventions and treatments of the deleterious effects of stress are to be established. This understanding will need to encompass the mechanisms of responses under a range of conditions, and in response to various stressors, as well as the effects of these responses on the body. The latter is not the focus of the current discussion but the former is. Individuals react to stressors in different ways and various physiological conditions including the sex of an individual will influence stress responses [1, 49]. Given that physiological responses to stress are important determinants for health, we will consider different types of stressors, sex differences in response to stress and the importance of physiological state, particularly reproductive state,

There are many different stressors that we encounter in our daily lives. It is commonly considered that stressors can be categorized as physical stressors or psychological stressors [1]. Physical stressors are those that pose a real threat to homeostasis and which result in "reactive" glucocorticoid responses to stress, whereas psychological stressors are those that

Diabetes Mellitus type II [37], hypertension [37] and major depression [37].

**3. Stress and health**

the stress response becoming pathological.

in influencing responses to stress.

**4. Different types of stressors**

are perceived to pose a threat to homeostasis and which result in "anticipatory" glucocorticoid responses to stress. Herman and colleagues [50] asserted that "reactive" glucocorticoid responses to stress are those induced by a genuine challenge to physiological homeostasis that is recognized by sensory pathways. Such challenges may include a change in cardiovascular tone, respiratory distress, pain or circulating cytokines. In such cases, there is a direct neuronal pathway to CRH neurons in the paraventricular nucleus via the brain stem to activate the hypothalamo-pituitary adrenal axis. In contrast, "anticipatory" glucocorticoid responses to stress are not mounted in response to an actual disruption to physiological homeostasis but to the anticipation of such a disruption. These responses require some higher cortical processing involving limbic pathways [50].

Physiological responses to physical stressors may be considered appropriate since the body is being prepared for a real threat and the elevated heart rate and blood pressure and energy stores mobilised by catecholamines and glucocorticoids (see Section 2) are required to deal with the stressor. For example, a direct physical threat may require vigorous skeletal muscle activity in order to avert detrimental consequences imposed by the stressor. Conversely, physiological responses to psychological stressors are potentially more harmful since the body does not usually need to respond with a physical use of energy, certainly not for a prolonged period. This would be evident where there may be a stressful environment induced without the need for physical exercise, such as being caught in traffic on the way to an important appointment. Heart rate and blood pressure may be elevated, and energy stores mobilized, but with no obvious benefit to dealing with the stressor. An exception would be the possible beneficial effects of increased mental acuity. Nevertheless, it follows that psychological stress may be detrimental to health, particularly if it is prolonged or repeated frequently, because it unnecessarily elevates heart rate and blood pressure and mobilizes energy stores placing unnecessary strain on essential physiological systems. It is important to appreciate that excessive activation of the stress systems can have a negative impact on normal physiological functioning [19, 20, 32].

Since different types of stressors activate the physiological stress systems via different mechanisms, it is important to consider different types of stressors when considering the roles of sex and the sex steroids in influencing the responsiveness of the sympatho-adrenal medullary system and the hypothalamo-pituitary adrenal axis.


**7. Poly(olefin sulfone)s composed of volatile monomers**

The photoinduced depolymerization of poly(olefin sulfone)s composed of volatile olefins was investigated [18]. The polymers were converted into volatile compounds by photoinduced depolymerization. A poly(olefin sulfone) film containing a photobase generator (ANC2) was irradiated with 254‐nm light at ambient temperature through a photomask. While very little change occurred in the film just after irradiation, the irradiated area of the film vaporized upon heating to 110**°**C, forming a mask pattern on the film (**Figure 19**). The surface of the film was also observed by AFM after heat treatment. The results confirmed that the irradiated area was removed, leaving a bare surface. This enables a wide variety of applications, such as stereolithography without the use of solvents, photo‐detachable adhesives, and printable nanocircuit fabrication.

**8. Application of photo‐depolymerizable poly (olefin sulfone)s to**

showed that depolymerizable polymers can act as detachable adhesives.

Detachable adhesives have attracted great interest due to their potential applications in reusable products and reworkable systems [22–26]. Adhesives used in many applications, and a variety of strong adhesives that can be employed in extreme environments have been developed [27]. However, most high‐performance adhesives are strongly adhesive, making them difficult to remove and therefore cannot be used in recyclable materials or in reworking processes. Therefore, a need exists for glues that provide firm bonding but also can be easily detached. The strength of an adhesive bond essentially depends on surface interactions between the adhesive material and the substrate. Therefore, if the chemical structure of the adhesive material can be changed after adhesion, the adhesion strength may also change. Studies have been reported on the adhesive strength of substrates fastened using degradable polymers [23, 24, 26]. The results

**Figure 19.** (a) Changes in a photomask pattern irradiated film during heating at 110**°**C. (b) AFM image of the photomask

Poly(olefin sulfone)s

137

http://dx.doi.org/10.5772/intechopen.69317

**photo‐detachable adhesives**

pattern irradiated area of the PMPS film after heating at 110**°**C for 15 min.

**Figure 19.** (a) Changes in a photomask pattern irradiated film during heating at 110**°**C. (b) AFM image of the photomask pattern irradiated area of the PMPS film after heating at 110**°**C for 15 min.


**3. Surfacing the ontological assumptions about corporate social responsibility**

The idea about CSR for UE-PG calls for the need for surfacing what could be its ontological positions. Drawing on powerful theories should allow for the better understanding and explanation by focusing on the role of agency. Critical realism philosophy and its argument for the study of reality as ontology challenge both the objective and socially constructed views about reality.  Such theories tend to be complacent about the natural necessity without fully addressing what might be the inadequacies of their claims. They tend to be dislocated from reality about a social reality/phenomenon and thus remain self-contained. They are more about surface ontology, that is, reducing the reality to the understanding and explanations thereof. To counter such a weakness, both critical realism philosophy and the realist social theory, as the explanatory program, allow the analyst to adopt a paradigm that is commensurable with the context and in ways that can be socially and culturally relevant and responsive. By the power of transcendence, the analyst is then able to question a type of science (pseudoscience) that selects what counts as reality and what reality to count to promote interests or socially constructed views.

**Table 1** suggests that corporate social responsibility can be understood and explained as an open and complex social system. Such systems take the three main elements of structure, culture, and agency. Drawing on the critical realist philosophy,

#### **Table 1.**

*The domains and social reality of corporate social responsibility as adapted from Dwayi [4].*

### *Reimagining Corporate Social Responsibility in the Idea of University Education as the Public… DOI: http://dx.doi.org/10.5772/intechopen.110177*

as the under laboring to the explanatory program as the social realism theory [2, 3] allows both for the understanding and the explanation of CSR for UE-PG as the interplay of systems at a particular point in time and space. The people inherit the conditions that aren't of their own making. As such, the present is always constituted from historical and social relations. For the future to possibly change for the better, that takes place through reflexivity and human action. Therefore, to surmise social realistoriented scholars, problem solving should entail the ability to engage the present in reflexive-dialectical processes that can allow for transformative agency to emerge.

The current challenges about CSR theories and practices, per already cited cases, call for the realist understanding of CSR as the agency as deep ontology, stratification, causal efficaciousness, and emergence. The social system elements of structure, culture, and agency (SCA) take two forms, the macro level, which is enduring because it derives from history and social relations, and the micro level, which can be enacted; hence it is regarded as the level of mediations. The explication of the elements of structure, culture, and agency (**Table 1**), firstly, as analytically distinct and secondly, as emergent from the three domains of reality, helps to accord the causal mechanism to each of the elements, including the power of agency as causally efficacious. In this regard, the personal emergent powers and properties (PEPPs) enable people to reflect upon their social context and to act reflexively toward it, either individually or collectively, objectively or subjectively. The significance of agency in resolving the problems about the primacy of structure in social science is when the PEPPs help humans to become active shapers of their socio-cultural contexts, rather than being the passive recipients thereof. Critical for social realism, therefore, is the question of how the chosen values and belief systems operate at the realm of agency [12].

Consequent to the first phase of the National Institutional Audits in South Africa (2008–2011), there was an increased voice from the critical realism scholars about the challenges of reporting about quality, when such reports can be seen to be drawing from de-ontological positions and self-referential explanations (details in the introductory section). As already indicated, the article does not seek to rewrite such a report but to focus on one such case of reporting by doing the critical realist analysis and the social realist account about the case of a historically disadvantaged university in South Africa. The main purpose is to advance the value of making a transcendental argument when engaging an issue as complex as evaluating and reporting about quality, incl the outlining of the challenges thereof, when engaging the topic CSR for UE-PG. Critical realist philosophy in terms of the domains of reality **Table 1** allows both for the principles and tools of analysis. The critical realist principles include judgmental rationality as the position against singular/single story explanations. The thinking tools thereof, namely, transfactuality, retroductive reasoning, and transcendental argument, allow for understanding of this philosophy as a metatheory, the tool about clearing the field or for under laboring the actual theory as the program of action, which is social realist theory. In this regard, social realism theory allows for the explanations of the social phenomenon (namely, corporate social responsibility) as interplays of structure, culture, and agency over time.

Therefore, the value of **Table 1**, as representative both of critical realism philosophy (the three domains about reality) and of social realism (the social world as structural, cultural, and human systems) is about thinking, hypothetically speaking, about the elements of structure, culture, and agency as analytically distinct and determining of causal efficaciousness (the relative weight of each element on the

other, especially structure, culture as sense and meaning making expressed as beliefs, norms, and standards). Because of the transitive and intransitive nature of the objects at the domain of the real, what then leads the critical oriented analyst is the transcendental question, that is, making an educated guess about,

*"What mechanisms must have been generating the kinds of the events and processes as those that are manifest at the domain of the actual and how the latter is further reflected as the empirical data?*

Therefore, one of the positions that make social realism to be a powerful explanatory program is the ability to apply its tools about rationality. One of those, relevant for the discussion, is transfactuality, that is, the ability to engage the assumption that, at empirical level, because the numbers are, or the statement is; the numbers or the statement thus serves as a measure of reality. Transfactuality allows for abductive logic as questioning the taken-for-granted views about what appears as empirical, because the observations and opinions at the domain of the empirical are the result of other two emergent layers (domain of the actual and the domain of the real) in non-deterministic and in irreducible ways. Therefore, this description of what the ontological assumptions can be about CSR for UE-PG seeks to foreground the role of agency (human system as choice or non-choices, as actions or no actions), which operates in dynamic relationships with the social and cultural systems, as indicated in **Table 1**.


3.3.5. Power Quality Constraints

These power quality constraints are imposed to ensure the quality of power integrated into the distribution system. Different power quality indices such as total harmonic distortion (THD), total demand distortion (TDD), displacement power factor (DPF), oscillation power factor (OsPF) and transmission efficiency power factor (TEPF) could be used for power quality evaluation. A single power quality index that represents these indices could be formulated to evaluate the power quality of the distribution systems.

The voltage magnitude constraints of the system can be reformulated and extended to impose constraints on the voltage harmonics of the distribution system during the integration of BESS/PVDG systems.

$$THD\_{\overline{v}} = \frac{\sqrt{\sum\_{h=2}^{\infty} V\_h^2}}{V\_1} \tag{3}$$

$$V\_{h(\min)} \le V\_h \le V\_{h(\max)}; \ h = 1, \dots, N \tag{4}$$

Similarly, the phase angle constraints could be formulated considering some parameters and assumptions that relate phase angle to active power (current) and can be extended to distribution networks if current harmonics are expected to be curtailed.

$$THD\_I = \frac{\sqrt{\sum\_{h=2}^{\infty} I\_h^2}}{I\_1} \tag{5}$$

$$
\theta\_{h(\min)} \le \theta\_h \le \theta\_{h(\max)} \; ; \; h = 1 \; \dots \; N \tag{6}
$$

#### *3.4. Modelling the Uncertainty of BESS/PVDGs*

Modelling the uncertainties of BESS/PVDG units, including BESS and solar PV units, and the uncertainties of loads are very important to obtaining accurate solutions for a BESS/PVDG optimal allocation problem. The uncertain parameters that can be modelled in the planning of an electric power system for accounting the uncertainties in the distribution system are also presented in Figure 3. However, several previous research works place the uncertainties of these resources into consideration in their formulation models. Some of the uncertainties that are being considered and modelled in BESS/PVDG optimization studies include uncertainties of solar irradiance, wind speed, PV modules, wind and solar DG units, uncertainties of fuel, generated power, electricity market price, uncertainty of BESS and uncertainty of loads [1,4,14].

**Figure 3.** Framework for optimizing BESS/PVDG into distribution networks.