Internal Regulatory Mechanisms Research Articles

The impact of macroeconomic and financial stress on the U.S. financial sector

During the 2008 global financial crisis, financial institutions in the United States experienced big losses, and some firms failed. These failures occurred despite the external and internal regulatory mechanisms imposed upon the financial sector aimed at ensuring confidence and stability in the financial system. This study analyzes the impact of macroeconomic and financial stress on the profitability of financial firms. We utilize data from 1980 to 2010 to model firm profitability and stock returns using a panel regression, fixed-effect methodology. Our results show that the profitability of all firms is negatively affected by increases in macroeconomic and financial stress, measured by the National Financial Conditions Index (NFCI) and the Adjusted National Financial Conditions Index (ANFCI), respectively; however financial sector firms have exhibited an increased marginal sensitivity to both stress indexes that began in the 1990s and continued through the financial crisis of 2008. In a further analysis of the financial sector and banks, we show that depository institutions are relatively robust to macroeconomic and financial stress, and financial sector instability is driven by non-depository finance, investment, and real estate firms. Additionally, the largest 33 percent of financial firms and banks exhibit increased sensitivity to macroeconomic stress in the most recent sample. Our results coincide with the risks associated with recent trends in the financial services industry, such as deregulation, global market integration, financial product innovation, and the increasing predominance of non-depository intermediation.

Ocean acidification may aggravate social-ecological trade-offs in coastal fisheries.

Ocean Acidification (OA) will influence marine ecosystems by changing species abundance and composition. Major effects are described for calcifying organisms, which are significantly impacted by decreasing pH values. Direct effects on commercially important fish are less well studied. The early life stages of fish populations often lack internal regulatory mechanisms to withstand the effects of abnormal pH. Negative effects can be expected on growth, survival, and recruitment success. Here we study Norwegian coastal cod, one of the few stocks where such a negative effect was experimentally quantified, and develop a framework for coupling experimental data on OA effects to ecological-economic fisheries models. In this paper, we scale the observed physiological responses to the population level by using the experimentally determined mortality rates as part of the stock-recruitment relationship. We then use an ecological-economic optimization model, to explore the potential effect of rising CO2 concentration on ecological (stock size), economic (profits), consumer-related (harvest) and social (employment) indicators, with scenarios ranging from present day conditions up to extreme acidification. Under the assumptions of our model, yields and profits could largely be maintained under moderate OA by adapting future fishing mortality (and related effort) to changes owing to altered pH. This adaptation comes at the costs of reduced stock size and employment, however. Explicitly visualizing these ecological, economic and social tradeoffs will help in defining realistic future objectives. Our results can be generalized to any stressor (or stressor combination), which is decreasing recruitment success. The main findings of an aggravation of trade-offs will remain valid. This seems to be of special relevance for coastal stocks with limited options for migration to avoid unfavorable future conditions and subsequently for coastal fisheries, which are often small scale local fisheries with limited operational ranges.

Effect of proquinazid and copper hydroxide on homeostasis of anions in winter wheat plants in generative phase of development

The study deals with the effect of proquinazid and copper oxide application on structural characteristics and resistance of wheat to powdery mildew, as well as remobilisation and redistribution of anions pools at generative stage of development. The trial series was conducted in the experimental agricultural production of the Institute of Plant Physiology and Genetics, National Academy of Sciences of Ukraine. Field experiments were carried out with Smuglyanka variety of winter wheat. The trial series included the application of fungicides such as Talius (proquinazid, 200 g/L) 0,25 L/ha and Kocide 2000 (copper hydroxide, 350 g/kg) 150 and 300 g/ha, and combination of both fungicides. Sprays were applied at tillering stage in autumn in the first trial series and at tillering-booting stage in spring in the second one. Assessment of affected plants by powdery mildew was carried out visually in points. Anion concentration was determined with the use of ion chromatography. Application of fungicides at tillering stage increases the amount of productive stems in wheat plants. The highest effect was recorded for application of copper hydroxide at dose of 300 g/ha in autumn. Analysis of plants affected by powdery mildew shows that application of proquinazid and its composition with copper hydroxide provides sustained protection against Blumeria graminis (DC) Speer. Application of fungicides at tillering stage contributes to increase of the pool of free nitrogen, phosphorus and sulfur anions in leaf tissues compared to control. These changes in anion composition may be caused by fungicide effect on activity of N, P, S transporters, as well as internal regulatory mechanisms of elements’ uptake by plants. Comparing the results of the autumn and spring application of fungicides should note the increase in concentration of free phosphates in wheat leaves in the 2nd trial with proquinazid and its composition with copper hydroxide. Accumulation of nitrogen in the nitrate form occur in the period of maximum activity of plants during grain maturation, that is why the increase of free nitrates concentration in all trial series may indicate the remobilization of nitrogen from vegetative organs to caryopsis. Analysis of wheat ear of the 1st trial shows increase in concentrations of free nitrates and phosphates in all trial series which may be explained by intensification of metabolic processes that occur in the ear during grain maturation. Comparison of results of 1st and 2nd trials shows the decrease of Cl concentration in plants of the 2nd trial which can be associated with extension of photosynthetic activity of leaves and participation of element in oxidative phosphorylation, as well as its binding with polypeptides belonging to photolysis complex of water of photosystem II. Thus, application of proquinazid and copper hydroxide at tillering stage increases the productive tillering capacity and enhances the pools of N, P, S free anions in winter wheat plants. These changes can be explained by the effect of fungicides on plant metabolic processes associated with remobilization and transport of elements from flag leaves to the ears during grain maturation. Autumn application of fungicides provides an excellent protection level against powdery mildew of winter wheat plants and creates optimal conditions for plants’ development and wintering. Treatment of plants in spring is highly effective against powdery mildew at tillering-booting stage.

ROS and Autophagy: Interactions and Molecular Regulatory Mechanisms.

Reactive oxygen species (ROS) and antioxidant ingredients are a series of crucial signaling molecules in oxidative stress response. Under some pathological conditions such as traumatic brain injury, ischemia/reperfusion, and hypoxia in tumor, the relative excessive accumulation of ROS could break cellular homeostasis, resulting in oxidative stress and mitochondrial dysfunction. Meanwhile, autophagy is also induced. In this process, oxidative stress could promote the formation of autophagy. Autophagy, in turn, may contribute to reduce oxidative damages by engulfing and degradating oxidized substance. This short review summarizes these interactions between ROS and autophagy in related pathological conditions referred to as above with a focus on discussing internal regulatory mechanisms. The tight interactions between ROS and autophagy reflected in two aspects: the induction of autophagy by oxidative stress and the reduction of ROS by autophagy. The internal regulatory mechanisms of autophagy by ROS can be summarized as transcriptional and post-transcriptional regulation, which includes various molecular signal pathways such as ROS-FOXO3-LC3/BNIP3-autophagy, ROS-NRF2-P62-autophagy, ROS-HIF1-BNIP3/NIX-autophagy, and ROS-TIGAR-autophagy. Autophagy also may regulate ROS levels through several pathways such as chaperone-mediated autophagy pathway, mitophagy pathway, and P62 delivery pathway, which might provide a further theoretical basis for the pathogenesis of the related diseases and still need further research.

Facts, Challenges, Difficulties and Hopes in Single-Cell Biology: Physiopathological Studies

Single-cell approaches are being increasingly used to unravel the many diverse mechanisms underlying biological processes that characterize each cell irrespective of the influx of other cells even within the same tissue. Consequently, the interference of metabolites and nervous stimuli emanating from the circulatory or nervous system in a higher organism like man is avoided. However, while the single-cell approach yields a wealth of data about single-cell metabolism and internal regulatory mechanisms, information about interactions and interrelations among similar or dissimilar cells may remain obscure. Starting from these considerations, here we summarize, without attempting to be exhaustive, some areas in which we think single-cell biological studies could be effective in translational medicine and in other areas of applied sciences. In this short review we describe the facts, challenges and perspectives related to these issues.

Economics of food intake in mice: Energy yield of the reinforcer

One of the Zeitgeists of the field for the study of ingestive behavior is that organisms are endowed with internal self-regulatory mechanisms that ensure optimal nutrition. However, the alarming increase in the prevalence of obesity challenges us to reconsider the extent to which internal regulatory mechanisms affect food intake, especially in a free market economy. Cued by the pioneering work of George Collier and his students, we have been examining food intake (demand) in mice when the effort or price of food is manipulated. We present two new experiments in mice that investigate the effect of energy yield per unit of food earned on working for food. The first experiment shows that when the nominal energy yield of each food pellet is halved by cellulose dilution, mice show relatively inelastic calorie-related demand despite the fact the cellulose diluted diet is unpalatable. The second experiment shows that the size of the pellet reinforcer does not have a major effect on food demand except in the extreme condition of small reward and high unit price. New analyses of distributions of responding are presented which suggest that mice work for “target” numbers of food rewards with only a small influence of price or energy gain.

Corporate Character Formation and CSR: The Function of Habit and Practice in the Mining Industry

The mining industry provides a rich context through which to engage the practical and ethical limits of Corporate Social Responsibility (CSR). Recent debates in organizational ethics have drawn attention to institutional constraints which inhibit awareness raising and ethical practice within corporate settings. During the last decade, the mining industry has come under increasing pressure to improve its environmental, social and ethical performance. In an effort to respond to these more ethically-orientated external expectations, the mining industry has developed a range of internal regulatory mechanisms and process, which can be applied individually or in conjunction with other companies and organizations. This combination of internal and external drivers indicates a growing imperative for mining companies to ground CSR principles in their day-to-day operating practices. The challenge is to avoid organizational rules and procedures for CSR that lack depth and meaning and which fail to result in the wise and courageous use of personal agency. Instead mining companies must work to establish appropriate mechanisms that will see ethical norms adopted as organizational principles that guide, and result in, improved corporate conduct. Using the Aristotelean notion of “character formation”, the authors offer practical considerations for how this might occur in the mining industry.

Transcriptional regulation of guidance at the midline and in motor circuits.

Axon navigation through the developing body of an embryo is a challenging and exquisitely precise process. Axonal processes within the nervous system harbor extremely complicated internal regulatory mechanisms that enable each of them to respond to environmental cues in a unique way, so that every single neuron has an exact stereotypical localization and axonal projection pattern. Receptors and adhesion molecules expressed on axonal membranes will determine their guidance properties. Axon guidance is thought to be controlled to a large extent through transcription factor codes. These codes would be responsible for the deployment of specific guidance receptors and adhesion molecules on axonal membranes to allow them to reach their targets. Although families of transcriptional regulators as well as families of guidance molecules have been conserved across evolution, their relationships seem to have developed independently. This review focuses on the midline and the neuromuscular system in both vertebrates and Drosophila in which such relationships have been particularly well studied.

Perseverance and effectiveness of action: the effect of the fit between individual differences in willpower and the situational context

<b>Background </b><br /> Invoking the fit theory between a person and the environ­ment, the author of which is Lawrence A. Pervin, an attempt to explain the influence exerted by willpower differences and the situational context on perseverance and action effectiveness is made. <br /> <br /> <b>Participants and procedure </b><br /> Two studies were conducted to test the effect of the situ­ational context and willpower differences on perseverance and action effectiveness. The first study involved <br /> 120 partici­pants (88 females and 32 males) between 17 and 19 years of age (M = 18.28; SD = 0.56). The researched group in the se­cond study included 230 participants (160 females and 70 males) between 20 and 53 years of age (M = 25.19; SD = 5.04). In the first study perseverance and action effectiveness were assessed on the basis of the performance level and the amount of time spent on the computer task. In the study 2 to evaluate the effectiveness used subjective progress assessment in achieving individual goals. In both of these studies, evoked a sense of autonomy vs. induced a sense of external control and the measurement of will-power differences was conducted on the basis of Kuhl’s ACS-90 questionnaire.<br /> <br /> <b>Results</b><br /> The results of study 1 confirm that perseverance and action effectiveness in the case of people with low will­power level (state-oriented) is greater in conditions creating a sense of pressure/external control. In the case of people with high willpower (action-oriented), the method of influencing by the situational context is not of major significance to their perseverance and effectiveness. The results of study 2 show that intention implementation in conditions creating a sense of external control increases progress assessment in achieving goals declared by the state-oriented. However, no positive influence of in­tention implementation on the assessments of progress made by action-oriented individuals was confirmed. <br /> <br /> <b>Conclusions</b><br /> The cumulative results of the two presented studies confirm that the perseverance and action effectiveness of people with low willpower (state-oriented) are determined by the specific kind of fit between personal predispositions and <br /> the situational context. In turn, people with high willpower (action-oriented) act, to a larger extent, on the basis of internal regulatory mechanisms, somehow regardless of the way in which the situational context exerts an influence on them.

SOCS3 Deletion in B Cells Alters Cytokine Responses and Germinal Center Output

B cell behavior is fine-tuned by internal regulatory mechanisms and external cues such as cytokines and chemokines. Suppressor of cytokine signaling 3 (SOCS3) is a key regulator of STAT3-dependent cytokine responses in many cell types and has been reported to inhibit CXCL12-induced retention of immature B cells in the bone marrow. Using mice with SOCS3 exclusively deleted in the B cell lineage (Socs3(Δ/Δ)mb1cre(+)), we analyzed the role of SOCS3 in the response of these cells to CXCL12 and the STAT3-inducing cytokines IL-6 and IL-21. Our findings refute a B cell-intrinsic role for SOCS3 in B cell development, because SOCS3 deletion in the B lineage did not affect B cell populations in naive mice. SOCS3 was strongly induced in B cells stimulated with IL-21 and in plasma cells exposed to IL-6. Its deletion permitted excessive and prolonged STAT3 signaling following IL-6 stimulation of plasma cells and, in a T cell-dependent immunization model, reduced the number of germinal center B cells formed and altered the production of Ag-specific IgM and IgE. These data demonstrate a novel regulatory signal transduction circuit in plasma cells, providing, to our knowledge, the first evidence of how these long-lived, sessile cells respond to the external signals that mediate their longevity.

Plant response to drought stress simulated by ABA application: Changes in chemical composition of cuticular waxes

Plant cuticles form the interface between epidermal plant cells and the atmosphere. The cuticle creates an effective barrier against water loss, bacterial and fungal infection and also protects plant tissue from UV radiation. It is composed of the cutin matrix and embedded soluble lipids also called waxes. Chemical composition of cuticular waxes and physiological properties of cuticles are affected by internal regulatory mechanisms and environmental conditions (e.g. drought, light, and humidity). Here, we tested the effect of drought stress simulation by the exogenous application of abscisic acid (ABA) on cuticular wax amount and composition. ABA-treated plants and control plants differed in total aboveground biomass, leaf area, stomatal density and aperture, and carbon isotope composition. They did not differ in total wax amount per area but there were peculiar differences in the abundance of particular components. ABA-treated plants contained significantly higher proportions of aliphatic components characterized by chain length larger than C26, compared to control plants. This trend was consistent both between and within different functional groups of wax components. This can lead to a higher hydrophobicity of the cuticular transpiration barrier and thus decrease cuticular water loss in ABA-treated plants. At both ABA-treated and control plants alcohols with chain length C24 and C26 were predominant. Such a shift towards wax compounds having a higher average chain length under drought conditions can be interpreted as an adaptive response of plants towards drought stress.

Secure attachment: implications for hope, trust, burnout, and performance

AbstractSecure attachment is a healthy attachment style that enables individuals to work autonomously as well as with others when appropriate. Secure attachments are characterized by internal regulatory mechanisms that allow individuals to be flexible and constructive in their interpersonal relationships Our model incorporates hope, trust in one's supervisor, and burnout as explanatory variables that translate the benefits of secure attachment into better supervisor‐rated task performance. Among 161 employees of an assisted living center and their supervisors, secure attachment had a significant, positive relationship with hope, trust, and burnout, but only trust had a significant, positive relationship with supervisor‐rated performance. These results indicate that secure attachment should be considered a positive psychological strength that has important implications for working adults. Copyright © 2009 John Wiley & Sons, Ltd.

Circadian variability in the photobiology of Phaeodactylum tricornutum: pigment content

Circadian variations of pigment content in the diatom Phaeodactylum tricornutum were analyzed in different light regimes. The study was aimed at discerning the role of putative endogenous controls from the constraint imposed by the alternation of light (L) and dark (D) periods. Our experiments showed that in a typical LD cycle of illumination, pigment synthesis follows the somatic growth of the cell, both arresting during D periods. In particular, the diurnal increase of chlorophyll a content was proportional to the increase in cell size and preceding cell division, occurring at night. By contrast, diadinoxanthin and β- carotene displayed different phases, which is likely to be related to their involvement in photoprotection mechanisms. The experiments also showed that the synthesis of both photosynthetic and photoprotective pigments was dependent not only on light availability and the phasing of somatic growth, but also responded to other internal regulation. Over the time scale of the experiments (hours to days), the removal of LD-DL triggers impaired cell physiology, whereas the circadian patterns in pigment synthesis persisted. Our results support the hypothesis that an internal regulation of cell biosynthetic machinery can improve phytoplankton fitness, even in high variable environments such as the oceanic mixed layers. Therefore, we suggest that phytoplankton growth depends not only on the availability of external resources, but also on internal regulatory mechanisms whose unveiling would further our understanding of phytoplankton diversity and dynamics.

Computational Models of Transcription Control: A Systems-Theoretic Perspective

In a gene network, genes may be expressed constantly, or expressed based on molecular signals. Transcription is a key process in gene expression. Through evolution, biological organisms have developed internal regulatory mechanisms for transcription control. Such mechanisms dictate how the network will function under certain environmental conditions and respond to changes in the environment. To develop formal approaches that enable the design and synthesis of such logical controls in artificial gene networks represents a major challenge. A first step in meeting this challenge would be to build analytical models of transcription control. This paper reviews computational approaches for modeling transcription control in gene networks from a systems-theoretic perspective, with emphasis on the logical representational capability of the models and their potential use in synthesis of external control. Keywords: Gene networks, computational models, transcription control, formal methods

Disciplinary cultures and academic leadership

Abstract The past 5 years have witnessed a concerted effort to regulate higher education by the government as part of its drive to redress the inequities of the past. One sees the twin problems of co-ordination and control reflected in this effort. From all indications, attention seems to be directed more to quantity of outputs, than to resources and processes with the result that universities appear to have been put in a situation in which they have to show that they are worth government's investment. There is the expectation on them to produce more and better results with ever diminishing resources per student. In the rush to respond positively to state demands, most universities have introduced programme-based degrees in place of discipline-based ones. To guarantee their survival, some universities have had to activate all their powers of innovation to find internal regulatory mechanisms considered suitable to academic work, or ‘invent’ their own models of management compatible with academic values. In...

Modelling reproduction in farm animals: a review.

During the last few decades, our knowledge of the biology of the reproductive system has improved significantly and also become more quantitative. In parallel, there has been an increase in the development of mathematical models, as both research tools and management tools, that can integrate our knowledge of reproductive events and then attempt to predict reproductive efficiency. This review considers these modelling approaches according to the level of organization that they address, from representation of the dynamic functions of the reproductive axis to the prediction of reproductive performance of a flock or herd. We emphasize the contribution of modelling to the exploration and understanding of a complex system-a system that responds to a host of internal regulatory mechanisms as well as to an array of external factors such as nutrition, photoperiod and sociosexual signals. To date, models have proven useful for depicting the kinetics of some of the endocrine signals that are implicated in perturbations of the reproductive axis and they have also been successful in the exploration of ovarian dynamics during the oestrous cycle. However, two areas are still largely unexplored by biomathematical models: the dynamic links between the different stages of the reproductive life of an animal, and mechanistic influences of environmental factors on the reproductive axis.

Metabolic complexity has no bearing on genetic determinism

Metabolic systems are complicated and contain very large numbers of interacting reactions and many internal regulatory mechanisms. This does not prevent the genetic composition of an organism from influencing its behavior, however, nor does it preclude the possibility that some aspects of its behavior may be amenable to simple explanations.

Academic regulation in UK higher education: part I ‐ the concept of collaborative regulation

The first of a series of three articles which map the dimensions and evolution of academic regulation in the UK. Argues that regulation is an important and substantial concept and set of activities which is far more comprehensive in scope and substance than the concept of quality assurance which it subsumes; that it involves the act of regulating (controlling and adjusting behaviour and practice against explicit or implicit rules) and the state of being regulated (practising within a framework of rules and accepted professional norms). Describes three basic types of regulatory regime ‐ self‐regulation, external regulation and mixed regimes ‐ and concludes that the size, complexity, diversity, history, public investment and interests in the UK higher education sector make it necessary to operate a mixed regime which incorporates elements of both external regulation and institutional self‐regulation. When viewed at the system level, the continuous interaction of external regulators with HE institutions, which have considerable autonomy over their internal regulatory mechanisms, is consistent with the concept of collaborative regulation (where co‐operation is both voluntary and mandatory).

Effect of glucose on growth and ultrastructural phenotype of Polytoma papillatum (chlamydophyceae)

Summary We used quantitative light microscopy and electron microscopy of serial sections, analysis of population growth characteristics, and experimental alteration of an individual exogeneous factor (± glucose) to investigate phenotype environment interactions of Polytoma papillatum further. Although the addition of 0.2% glucose to the standard liquid nutrient induced acceleration of reproduction under batch culture conditions, neither the final number of cells nor their span of variability in shape and volume were markedly influenced by glucose supplementation. Compared with cells grown in standard medium, cells exposed to a glucose supplemented environment showed changes in the shape, number, and ultrastructure of the mitochondrial inventory (= chondriome) and in ultrastructure of the nucleolus and leucoplast. Whereas a volumetric balance existed between the cell and the chondriome during both culture conditions, the glucose supplementation brought about (1) an increase in the total number of mitochondria, (2) a numerical increase in intramitochondrial matrix grana, and (3) a change in spatial distribution of the chondriome, indicating profound modifications of the chondriome. Glucose also affected the spatial distribution of nucleolar constituents and caused local diversifications of the leucoplast. The adaptive nature of these responses to the glucose-stimulus is discussed with regard to internal regulatory mechanisms causing or permitting phenotypic expression.

Stability conditions of cell populations in vivo

Specific exogenous stimulating and inhibiting substances act on cell proliferation and differentiation rates. An additional internal regulatory mechanism is shown to be necessary to ensure the regulation of cell proliferation in vivo. Various internal regulatory mechanisms have been envisaged. Stability conditions and experimental data led us to reject all of them except those postulating that an inhibitory signal produced by the differentiating cells acts on the rate of cell proliferation. This finding supports the theory concerning the mechanism of action of "chalone-like" inhibiting substances.