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El presente artículo se enmarca en una investigación con enfoque mixto, desde el enfoque cualitativo con métodos de etnometodología y teoría fundamentada desde lo deductivo racionalista, nivel explicativo, con apoyo en una investigación de campo, de naturaleza cuantitativa, técnica de análisis factorial confirmatorio. El objetivo de la propuesta fue identificar factores que inciden al implementar la consejería académica y de investigación en el fomento de la convivencia, dirigida a estudiantes universitarios e identificar percepciones de docentes desde la perspectiva de la investigación. La población la constituyen 25 docentes con doctorado en el Departamento Norte de Santander y directivos de instituciones de educación superior. La entrevista, encuesta y análisis documental se utilizaron como instrumentos. Resultados: Factores económico, motivacionales, sicológicos, políticos, de carga académica, afectan la conciliación, empatía, labor investigativa y de asesoría académica de profesionales con doctorado en las universidades. Conclusión: la Consejería académica y de investigación, mejora la interacción social, convivencia, formación investigativa de la comunidad académica, brinda espacios de desarrollo de investigación de profesionales con doctorado. This article is part of a research with a mixed approach, from the qualitative approach with methods of ethnomethodology and theory based on the deductive rationalist, explanatory level, with support in a field research, quantitative nature, confirmatory factorial analysis technique. The objective of the proposal was to identify factors that influence the implementation of academic and research counseling in the promotion of coexistence, aimed at university students and to identify perceptions of teachers from the perspective of research. The population consists of 25 teachers with doctorates in the Department of Norte de Santander and executives of institutions of higher education. The interview, survey and documentary analysis were used as instruments. Results: Economic, motivational, psychological and political factor and academic load affect the conciliation, empathy, research and academic advisory of professionals with doctorate in universities. Conclusion: Academic and research counseling improves social interaction, coexistence, research training of the academic community, provides opportunities for research development of professionals with doctorates. O presente artigo faz parte de uma pesquisa de abordagem mista, da abordagem qualitativa com métodos de etnometodologia e teoria baseada no nível dedutivo e explicativo racionalista, com suporte em uma pesquisa de campo quantitativa, técnica de análise de fator confirmatório. O objetivo da proposta foi identificar fatores que afetam a implementação de aconselhamento acadêmico e de pesquisa na promoção da convivência, voltado para estudantes universitários e identificar percepções de professores na perspectiva da pesquisa. A população é composta por 25 professores com doutorado no Departamento de Norte de Santander e diretores de instituições de ensino superior. A entrevista, pesquisa e análise documental foram utilizadas como instrumentos. Resultados: fatores econômicos, motivacionais, psicológicos, políticos e acadêmicos, afetam a conciliação, empatia, trabalho de pesquisa e aconselhamento acadêmico de profissionais com doutorado em universidades. Conclusão: aconselhamento acadêmico e de pesquisa, melhora a interação social, a coexistência, o treinamento de pesquisa da comunidade acadêmica, oferece oportunidades de desenvolvimento de pesquisa de profissionais com doutorado

Late arrival on the breeding grounds has been associated with reduced fitness in migratory birds. Because migratory stopover accounts for the majority of time spent on migration, how individuals respond to both exogenous and endogenous factors associated with stopover will influence the pace of migration and arrival timing on the breeding grounds. Among the most important endogenous factors, body condition (i.e. fat stores) is expected to influence both movement behavior and departure decisions of individual migrants during stopover. In a novel experiment, we manipulated the condition of after-second-year (adult) male American Redstarts (Setophaga ruticilla) captured during spring migratory stopover and radio-tracked all individuals after release using a passive automated telemetry array and conventional hand tracking. After accounting for the positive effect of tailwind and capture date on departure probability, we demonstrated that body condition influenced both the movement behavior of individ...

Hair disorders are common in clinical practice and depending upon social and ethnic norms, it can cause significant psychosocial distress. Hair growth, cycling and density are regulated by many endogenous factors, mainly circulating hormones. Thus, diseases affecting the endocrine system can cause varied changes in physiological hair growth and cycling. Diagnosis and treatment of these disorders require a multidisciplinary approach involving a dermatologist, gynecologist and an endocrinologist. In this review, we briefly discuss the influence of hormones on the hair cycle and hair changes in various endocrine disorders.

Atopic dermatitis - chronic allergic skin inflammatory disease with genetic predisposition, dysbalance of immune response, dysfunction of an epidermal barrier and influence of various exogenous and endogenous factors. Epidermal barrier dysfunction leads to rising of permeability of a skin for allergens, microbs and nonspecific stimuli, as well as to sensitivity to various external influences. Clinically these implications are shown by skin xerosis symptoms therefore. According to modern clinical guidelines, the moisturizing agents, so called emollients, have to be used at all disease stages. Own data on use of modern skin care series Atopic® in complex therapy of atopic dermatitis patients are presented in the article.

Juvenile to adult phase transition is a crucial part of plant life cycle. In potato, initiation of tuber development marks the beginning of such transition. Several environmental and endogenous factors have been implicated in tuber developmental process (tuberization) in potato. Photoperiod, temperature, plant age, activity of hormones, mobile RNAs and proteins are important cues that control potato tuberization. Recently, microRNAs (miRNAs) are shown to interact with these factors and play an integral role in determining the tuberization fate. This review discusses the current knowledge on function of miRNAs towards the tuberization process in potato.

This paper examines the impact of remittances on poverty measures in transition economies using the panel data for the sample of nine countries in the period of 2002-2013. LSDV (Least Squares Dummy Variable) model with panel-corrected standard errors is used for estimation of remittance effects. The results show that remittances have a significant impact on each of the three poverty measures. Taking into consideration the endogenous regressor problem, a 10-percent increase in remittances per capita will lead to a decline, on average a 4.7 percent in poverty headcount, and also 5.2 percent in poverty depth and 5.8 percent in poverty severity. These results can be important for defining the policy measures on providing more efficient management of remittances.

Biochemistry of post-mortem muscle tissue is complex, and several factors affect the fresh meat color and color stability, both of which influence consumer acceptance. Therefore, improving meat color and meat color stability is of significant value to the meat industry and consumers. While extensive literature is available on the color and color stability of domestic ungulates, literature on wild ungulates is notably lacking. With an increasing global demand for meats from wild ungulates, it is critical to identify the knowledge gaps regarding their color and color stability. The objective of this paper is to overview the exogenous and endogenous factors influencing the color and color stability of fresh meats from domestic and wild ungulates. The literature highlighted that the pre- and post-harvest factors influencing meat color and meat color stability are interrelated and not mutually exclusive. Current research indicates that the effects of several of these factors are specific to species, breed, and muscle source. Novel ways to manipulate these factors using a biosystems approach should be explored to improve color attributes of fresh ungulate meats.

The number of preclinical studies that use drugs or endogenous factors for various targetable sites aiming to improve islet function and engraftment has recently gained more interest. Several molecules have been proposed to support and augment the functionality of islets. Here, we review five different classes of beta cell protection factors, classified as antioxidants, anti-inflammatory, anti-apoptotic, immunomodulatory, vascularization enhancers, and promoter of beta cell proliferation and function and their effect on islet grafting and function after transplantation in animal models of type 1 diabetes.

The paper focuses on tracing the origins of learning difficulties with the view of laying a foundation for their mitigation. While learning difficulties are variously understood, this paper argues for a conceptualization that differentiates them from learning disabilities. Therefore, the endogenous and exogenous originating factors of learning difficulties that are examined in this paper are aligned to the conceptualization that learning difficulties are temporary and can therefore be minimized or eliminated as a function of usage of appropriate intervention. The paper, however, acknowledges that the major sources of learning difficulties are of organic origin and thus endogenous. For the exogenous originating factors, schools have a direct role to play but can only be effective if they forego the traditional practice of ignoring the fact that schools and teachers are in effect part of the originators of learning difficulties. Thus, it can be concluded from this paper that, awareness of the origins of learning difficulties is the first concrete step toward minimizing or eliminating them and that the school plays a central role in these regards. To achieve a meaningful central role in minimizing or eliminating learning difficulties however, schools must be conscious of internal variables that cause learning difficulties and deal with them decisively before blaming or attending to other originating factors. In addition, they should be aware of and always look out for the general indicators of learning difficulties.

The thyroid gland is the most acceptable organ for autoimmune processes due to the negative effects of exogenous and endogenous factors on the background of genetic predisposition. A multifaceted study of the risk factors of the occurrence and progression of autoimmune thyroid diseases (AITD) will prevent the rapid manifestation of this pathology in patients with problematic heredity background. The objective: to conduct a systematic analysis of available literature sources for the study of the risk factors of the occurrence and progres sion of AITD. Materials and methods. Clinical trials were found on the JAMA, Scholar, NCBI, Cochrane Library and PubMed databases for the 2007 2017 for keywords related to the risk factors and AITD without regard to their design. Results. The analyze of 83 articles in which the risk factors for the occurrence of AITD were studied. During the last 10-years, more attention was paid to the study of such factors as a genetic, microelements and vitamins, as well as associations with viral and systemic autoimmune diseases and their treatment. Frequency and prevalence of individual risk factors for AITD varies widely enough, depending on the design of the study and the number of subjects surveyed. In most cases, AITDs were associated with heredity, especially in the two following generations (>77%), vitamin D deficiency (>70% of patients), atrophic gastritis (>75% of cases), changes of the intestine microbiocynosis (>60%). Less important were factors such as iodine deficiency (14,5%), selenium (3,4%), tobacco smoking (15,4%), ionizing radiation (from 8,2% in the first generation to 45,5% in III generations), viral diseases and their treatment. Conclusions. Despite the large number of studies, the issue of the impact of risk factors of the occurrence and progression of AITD still remains poorly understood.

Urinary bladder cancer (UBC) is one of the most common malignancies worldwide. The etiology of UBC is multifactorial and includes both exogenous and endogenous factors. Exogenous risk factors include exposure to heavy metals, aromatic amines, and environmental pollutants including pesticides such as organochlorine pesticides (OCPs). Environmental factors alone are incapable of directly producing DNA damage and may require activation by phase I metabolizing enzymes like cytochrome P450 in order to become active carcinogen. The present study is designed to study CYP1A1 gene expression, OCP level in cases of UBC, as well as to explore the plausible role of gene–environment interaction in the etiology of UBC among North Indian population. A total of 60 cases with equal number of controls were enrolled under this study, the OCP levels were estimated using gas chromatography, CYP1A1 mRNA expression was quantified by real-time quantitative polymerase chain reaction, and fold change was calculated using the ΔΔCt method. In the present study, the levels of OCP were found to be significantly higher with the upregulation of CYP1A1 mRNA expression among UBC cases as compared to controls. While putting multiple linear regression, it has been observed that there is a significant interaction between the levels of OCPs and ΔCt value of CYP1A1 gene taken into account hematuria episodes as dependent variable. The study concludes that when there is predisposition of OCPs and upregulation of CYP1A1 gene, then the result will be an increment in hematuria episodes which indicates that gene–environment interaction plays a significant role in the causation of UBC among North Indian population.

This study investigates how the endogenous factors of public projects affect carbon performance. Taking the logical framework approach, a research model and hypotheses are proposed to evaluate the effects of endogenous project factors, including human resources, funding, materials, and project management methodology on project carbon performance. Questionnaires were distributed to project professionals in China and a structural equation model was deployed to analyze these effects. The results show that funding, materials, and project management methodology have a significant influence on public project carbon performance, whereas human resources have no significant effects. Recommendations on how to improve carbon performance are provided.

This research presents the behavior of the Mexican unemployment rate and shows the dependence with own history and macro variables. The concept of hysteresis or persistence tries to separate this inertia in the unemployment rate and some macroeconomic and endogenous factors. The results show a high inertia in the Mexican labor market, justified by the monetary levels and the dependence of the investment levels, considering the shocks of exports that affect the unemployment in the long term.

The aim of the paper is to analyse regional growth factors in Central and Eastern European Countries in the pre- and post-crisis era. The comparison is focused on core (metropolitan) and non-core (non-metropolitan) regions. The study found that the development processes of the analysed groups of regions were in many respects similar. Achieving a high level of development in the context of post-socialist transformation was possible mainly owing to exogenous factors such as the influx of foreign direct investment (FDI) and multimodal transport accessibility. In the case of endogenous factors, the number of small- and medium-sized enterprises per capita was of cardinal importance for a high level of development, but it was no guarantee of fast growth dynamics in non-core regions. The main differences between the core and non-core regions included the role of human capital and migrations as metropolitan regions represented growth poles which trained qualified specialists and served as destinations for...

The paper presents an analysis of the shift in the ownership policy of the Polish government in office since 2015 towards a more active role of the state and a more reluctant attitude towards privatisation. This shift reflects a general change in the paradigm of the role of the state towards the concept of the state as a strong market player, which includes the strengthening of its ownership functions. Among others, it has led to stalling the privatisation process and concentrating only on its fiscal goals. Possible factors causing this statist shift are divided into two dichotomic groups: the government’s good faith vs. the impact of rent-seeking interest groups and endogenous vs. exogenous factors. Our main conclusion is that despite similarities with the trends observed in some other countries, endogenous factors such as increasing capture of the state by rent-seeking groups, and not the exogenous ones, including the global financial crisis, contributed most to the growing statist trends in the Polish state’s ownership policy.

Significant progress has been achieved in the development of stimuli-responsive nanocarriers for drug delivery, diagnosis, and therapy. Various types of triggers are utilized in the development of nanocarrier delivery. Endogenous factors such as changes in pH, redox, gradient, and enzyme concentration which are linked to disease progression have been utilized for controlling biodistribution and releasing drugs from nanocarriers, as well as increasing subsequent pharmacological activity at the disease site. Nanocarriers which respond to artificially-induced exogenous factors (such as temperature, light, magnetic field, and ultrasound) have also been developed. This review aims to discuss recent advances in the design of stimuli-responsive nanocarriers which appear to have a promising future in medicine.

In observation of the first US multilateral collaborative program in advanced fighter-jet production, the F-35 JSF, I analyze the implications of the so-called defense-industrial globalization phenomenon for the Northeast Asian region by examining the fighter-jet acquisition patterns of South Korea, Japan, and Taiwan. I explore the applicability of the Varieties of Defense-Industrial Capitalism (VoDC) model, put forth by Marc R. Devore, which places emphasis on endogenous-institutionalist factors in projecting the adaptation patterns of states to defense-industrial globalization. By revealing theoretical and empirical limitations of the VoDC model when applied to Northeast Asia's fighter-jet industry, I argue that the Northeast Asian varieties of paths are a complex outcome of not only their endogenous settings but also US exogenous influence on the region. I also show that Devore's institutionalist and liberalist thesis on defense-industrial globalization does not hold for the cutting-edge fighter-jet in...

We estimate a structural dynamic model of the determinants of obesity. In addition to including many of the well-recognized endogenous factors mentioned in the literature as obesity determinants, we also model the individual’s residential location as a choice variable, which is the main contribution of this paper to the literature. This allows us to control for an individual's self-selection into communities that possess the types of amenities in the built environment, which in turn affect their obesity-related behaviors such as physical activity (PA) and fast food consumption. We specify reduced form equations for a set of endogenous demand decisions, together with an obesity structural equation. The whole system of equations is jointly estimated by a semi-parametric full information log-likelihood method that allows for a general pattern of correlation in the errors across equations. Our model predicts a reduction in adult obesity of 7 percentage points as a result of a continued high level PA from adolescence into adulthood; a reduction of 0.7 (3) percentage points in adult obesity as a result of one standard deviation reduction in weekly fast food consumption for women (men); and a reduction of 0.02 (0.05) in adult obesity as a result of one standard deviation change in several neighborhood amenities for women (men). Another key finding is that controlling for residential self-selection has substantive implications. To our knowledge, this has not been yet documented within a full information maximum likelihood framework.

Although violence against women is now spoken more freely than ever, there is still a high dark figure of crime in this type of violence, especially domestic violence, which should be reduced. After the analysis of the phenomenology of violence, and then the etiology, as well as the situation in our country, as well as the countries of the former SFRY, the analysis of the data obtained by the performed research is presented in the dissertation. All of this together makes one of the whole from which one can draw the conclusion that it is the weakest areas in which the state, but also the society can take measures to prevent the occurrence of violence against women or reduce it. The main research objective could be formulated as a search for statistical data on the phenomenological and etiological characteristics of violence against women, with particular reference to domestic violence as the most common type of violence against women. Scientific research should determine the degree of progress in the development of society in terms of recognizing human rights for all and under equal conditions. The phenomenology of violence against women should show what are the basic forms of violence that women face and whether they are exposed to this type of violence simply because they are women or are not gender-based violence. A comparative legal analysis of violence would show what difficulties the countries in the region face regarding the issue of violence against women. Whether in all these countries domestic violence is a criminal offense or not, what are the penalties provided for the perpetrator? Finally, on the basis of theoretical analyzes and empirical research, the prevention measures will be outlined and ways to reduce violence against women in society.

It is well known that the response of individuals to disease varies, either because of unpredictable exogenous events, such as possibly unknown environmental effects, or just because of endogenous factors, i.e. different genetic background. In particular, when a treatment effectiveness has to be validated, the individual variability should be taken into account by exploiting stochastic models. Relapsing Remitting Multiple Sclerosis (RRMS) is an unpredictable and complex disease, whose random behaviour perfectly fits the study with stochastic models. RRMS is the most common form of Multiple Sclerosis (MS), an immune-mediated inflammatory disease of the central nervous system, characterized by alternate episodes of symptom exacerbation (relapses) with periods of disease stability (remission). Several treatments were proposed to contrast the disease progression. Among these, Daclizumab initially exhibited promising results. However, due to the risk of serious side effects the treatment has been retired. We propose a stochastic and an hybrid extension, based on a generalization of the high level Petri Net formalism, of an existing model of Daclizumab effects on RRMS. The model is developed to investigate the complex mechanisms and unpredictable behaviour characterizing the RRMS disease and its relapsing, especially under the Daclizumab administration.

Los estereotipos ayudan a entender el mundo; a diferenciar lo bueno y lo malo, ellos nos brindan una idea sobre el tipo de grupo o conducta que se debe tener para ciertos roles sociales siendo así construcciones subjetivas de un individuo o grupo de individuos que es realizada sobre otros individuos o grupo; simplificando la realidad y generando ser positivos, negativos o neutrales convirtiéndose en construcciones sin fundamento científico. Los estereotipos según la RAE “Son una imagen o idea aceptada comúnmente por un grupo o sociedad con carácter inmutable “y con esto se observa que las nuevas generaciones han nacido y crecido unidos a la tecnología, los medio masivo y redes sociales convirtiéndose en idea común dentro de su vida cotidiana y con lo que se ha creado una nueva forma de comunicación masiva que ha permitido la inclusión de nuevos estereotipos sociales. Pero como se sabe al pasar del tiempo, llegamos a un punto en el que nos llenamos de ideales por los cuales buscamos a toda costa buscar cumplir con lo que todo el mundo usa o lo que está de moda establecido por marcas y personas con influencia colocando estándares de vidas altos y con esto nos lleva a que surja la pregunta: ¿Qué ocurre cuando no podemos cumplir los estándares sociales a causa de no tener recursos económicos suficientes? En esta investigación en curso propone encontrar diferentes puntos de vistas de teóricos que nos muestra las consecuencias que pueden traer el apropiar estereotipos en busca de aceptabilidad social pudiendo pasar incluso por encima de nuestros principios e ideales. Stereotypes help to understand the world; to differentiate the good and the bad, they give us an idea about the type of group or behavior that must be had for certain social roles, thus being subjective constructions of an individual or group of individuals that is performed on other individuals or groups; simplifying reality and generating positive, negative or neutral becoming constructions without scientific foundation. Stereotypes according to the RAE "They are an image or idea commonly accepted by a group or society with an immutable nature" and with this it is observed that new generations have been born and grown together with technology, the mass media and social networks becoming a common idea within his daily life and with what he has created a new form of mass communication that has allowed the inclusion of new social stereotypes. But as we know over time, we reach a point where we are filled with ideals for which we seek at all costs to seek to comply with what everyone uses or what is in fashion established by brands and people with influence placing standards of high lives and with this leads us to the question: What happens when we cannot meet social standards because of not having sufficient economic resources? In this ongoing investigation, he proposes to find different points of view of theorists that shows us the consequences that stereotypes can bring in search of social acceptability and may even exceed our principles and ideals. Pregrado

Ageing population suffer from increased risk of malnutrition which is a major determinant of accelerated loss of autonomy, adverse health outcomes and substantial health-care costs. Malnutrition is largely attributed to reduced nutrient intake, latter may be associated with several endogenous factors, such as, decline of muscle mass, oral functions and coordination that can make the eating process, difficult. From an exogenous viewpoint, nutritionally-dense foods with limited innovations in food texture have been traditionally offered to elderly population that negatively affected pleasure of eating and ultimately, nutrient intake. Recent research has recognised that older adults within the same age group are not homogenous in terms of their preferences, nutritional needs, capabilities and impediments in skill-sets. Hence, a new term ‘eating capability’ has been coined to describe various quantifiable endogenous factors in the well-coordinated eating process that may permit characterisation of the capabilities of elderly individuals in food handling and oral processing. This review covers current knowledge on eating capability focusing on parameters, such as hand and oro39 facial muscle forces. Although limited in literature, eating capability score measured using a comprehensive toolkit has shown promise to predict eating difficulty perception and oral processing behaviour. Further systematic studies are required to explore relationships between individual/multiple constituents of eating capability and oral comfort. Such knowledgebase is needed to underpin the creation of next generation of personalised texture-modified foods for elderly population using sophisticated technologies, such as 3D printing to enhance eating pleasure, increase nutrient intake that will ultimately contribute to tackling malnutrition.

Introduction. Oxygen, reacting with organic compounds in living organisms, oxidizes them without being completely reduced due to numerous exogenous as well as endogenous factors. As a consequence, free radicals or reactive oxygen species are formed. Health resort-based balneophysiotherapy is a comprehensive therapeutic intervention that triggers positive therapeutic effects within the entire system. Material and Methods. The objective of the study was to assess the impact of health resort-based balneophysiotherapy on the levels of nonenzymatic endogenous antioxidants in patients with degenerative motor organ diseases, as well as to determine potential correlation of these changes with free radical-mediated processes. Observation was carried out in patients undergoing health resort therapy as part of 21-day stay periods. The study population consisted of n=110 patients with articular and spinal pains due to degenerative diseases or discopathies. Results. Reduced bilirubin and albumin levels as well as increased uric acid levels were observed in the study group following the health resort treatment. Conclusions. Bilirubin and albumin levels were reduced while uric acid levels were increased as the result of health resort therapy in patients with degenerative motor organ diseases. The observed changes in the levels of nonenzymatic endogenous antioxidants depend on free radical-mediated systemic transformations. The trial is registered with NCT03405350.

Both seed germination and early seedling establishment are important biological processes in a plant's lifecycle. Seed longevity is a key trait in agriculture, which directly influences seed germination and ultimately determines crop productivity and hence food security. Numerous studies have demonstrated that seed deterioration is regulated by complex interactions between diverse endogenous genetically controlled factors and exogenous environmental cues, including temperature, relative humidity, and oxygen partial pressure during seed storage. The endogenous factors, including the chlorophyll concentration, the structure of the seed coat, the balance of phytohormones, the concentration of reactive oxygen species, the integrity of nucleic acids and proteins and their associated repair systems, are also involved in the control of seed longevity. A precise understanding of the regulatory mechanisms underlying seed longevity is becoming a hot topic in plant molecular biology. In this review, we describe recent research into the regulation of seed longevity and the interactions between the various environmental and genetic factors. Based on this, the current state-of-play regarding seed longevity regulatory networks will be presented, particularly with respect to agricultural seed storage, and the research challenges to be faced in the future will be discussed.

As heterogeneous immune cells, macrophages mount effective responses to various internal and external changes during disease progression. Macrophage polarization, rather than macrophage heterogenization, is often used to describe the functional differences between macrophages. While macrophage polarization partially contributes to heterogeneity, it does not completely explain the concept of macrophage heterogeneity. At the same time, there are abundant and sophisticated endogenous and exogenous substances that can affect macrophage heterogeneity. While the research on endogenous factors has been systematically reviewed, the findings on exogenous factors have not been well summarized. Hence, we reviewed the characteristics and inducing factors of heterogeneous macrophages to reveal their functional plasticity as well as their targeting manoeuvreability. In the process of constructing and analysing a network organized by disease‐related cells and molecules, paying more attention to heterogeneous macrophages as mediators of this network may help to explore a novel entry point for early prevention of and intervention in disease.

The cancerous process is result of disturbed cell function. This is due to the accumulation of many genetic and epigenetic changes within the cell, expressed in the accumulation of chromosomal or molecular aberrations, which leads to genetic instability. It is difficult to assess the validity of individual aetiological factors, but it can be concluded that interaction of various risk factors has the largest contribution to the cancer development. Environmental, exogenous and endogenous factors as well as individual factors, including genetic predisposition contribute to the development of cancer. Epidemiological research on the development of malignant tumors has focused over the years on the determinants of environmental and genetic factors of cancer incidence and mortality rate. According to current state of knowledge, 80–90% of malignant tumors are caused by external environmental factors (carcinogens). Epidemiological studies have proved that the main factors responsible for the development of malignant neoplasia among humans are environmental factors arising from human behaviour. It has been confirmed that smoking, excessive alcohol consumption, diet, and reproductive behaviour are important for the development of malignant neoplasia in the human population. According to the World Health Organization, in 2020 we may expect about 10 million deaths, including 7–8 million in the developing countries, while this number in the developed countries will not change and will be 2–3 million. The aim this study was systematization of knowledge concerning the risk factors of malignant tumours and supplementing them with the latest research results.

Endocrine factors regulate food intake and growth, two interlinked physiological processes critical for the proper development of organisms. Somatic growth is mainly regulated by growth hormone (GH) and insulin-like growth factors I and II (IGF-I and IGF-II) that act on target tissues, including muscle, and bones. Peptidyl hormones produced from the brain and peripheral tissues regulate feeding to meet metabolic demands. The GH-IGF system and hormones regulating appetite are regulated by both internal (indicating the metabolic status of the organism) and external (environmental) signals. Among the external signals, the most notable are diet availability and diet composition. Macronutrients and micronutrients act on several hormone-producing tissues to regulate the synthesis and secretion of appetite-regulating hormones and hormones of the GH-IGF system, eventually modulating growth and food intake. A comprehensive understanding of how nutrients regulate hormones is essential to design diet formulations that better modulate endogenous factors for the benefit of aquaculture to increase yield. This review will discuss the current knowledge on nutritional regulation of hormones modulating growth and food intake in fish.

A fundamental question in ecology is whether vegetation oscillations are merely a result of periodic environmental variability, or rather driven by endogenous factors. We address this question using a mathematical model of dryland vegetation subjected to annual rainfall periodicity. We show that while spontaneous oscillations do not exist in realistic parameter ranges, resonant response to periodic precipitation is still possible due to the existence of damped oscillatory modes. Using multiple time-scale analysis, in a restricted parameter range, we find that these endogenous modes can be pumped by the exogenous precipitation forcing to form sustained oscillations. The oscillations amplitude shows a resonance peak that depends on model parameters representing species traits and mean annual precipitation. Extending the study to bistability ranges of uniform vegetation and bare soil, we investigate numerically the implications of resonant oscillations for ecosystem function. We consider trait parameters that represent species with damped oscillatory modes and species that lack such modes, and compare their behaviors. We find that the former are less resilient to droughts, suffer from larger declines in their biomass production as the precipitation amplitude is increased, and, in the presence of spatial disturbances, are likely to go through abrupt collapse to bare soil, rather than gradual, domino-like collapse.