Highlights in gibberellin research A tale of the dwarf and the slender

It has been almost a century since biologically active gibberellin (GA) was isolated. Here, we give a historical overview of the early efforts in establishing the GA biosynthesis and catabolism pathway, characterizing the enzymes for GA metabolism, and elucidating their corresponding genes. We then highlight more recent studies that have identified the GA receptors and early GA signaling components (DELLA repressors and F-box activators), determined the molecular mechanism of DELLA-mediated transcription reprograming, and revealed how DELLAs integrate multiple signaling pathways to regulate plant vegetative and reproductive development in response to internal and external cues. Finally, we discuss the GA transporters and their roles in GA-mediated plant development

Imaging the Woman through Tanzanian Women’s Maxims

Women’s maxims, as well as other forms of oral literature in Tanzania, are a popular genre. They are verbal arts that can be self-addressed or addressed to a fellow woman among womenfolk. This paper intends to examine the role of these maxims in imaging women in Tanzania. This study was prompted by the findings of previous studies regarding the portrayal of women in Kiswahili literature where, generally, women are depicted as inferior beings compared to men, partly due to the fact that most authors are men. Hence, we found it imperative to investigate women’s maxims that are created and uttered by women themselves. The study was also prompted by other studies worldwide on language and gender. The questions to be addressed in this paper are: What is generally portrayed in such maxims? Why do women create, use and perpetuate such maxims? How do women consider themselves in relation to men? The data of this study was collected in Dar es Salaam through interviews and observation techniques. This study is significant to literary critics, sociolinguists, gender practitioners, cultural theorists and researchers on women studies. The study revealed that women’s maxims make much contribution to group identity formation, gender relations and culture. Through these maxims women marginalize their role, empower themselves, create gender constructs and gender differences and give themselves new outlook in the modern society

Too Good for Your Job? Disentangling the Relationships Between Objective Overqualification, Perceived Overqualification, and Job Dissatisfaction

In the present study, we investigated the relationships between objective overqualification, perceived overqualification, and job satisfaction based on the tenets of P-E fit theory, a commonly-used theoretical framework in the overqualification literature. Specifically, we tested whether employee perceptions of overqualification mediate the relationship between objective overqualification and job dissatisfaction. Results across two studies indicated that objective overqualification and job satisfaction independently predicted perceived overqualification, which contradicts the prevailing view in the literature of unidirectional effects between overqualification and strain outcomes. Study 1 used a cross-sectional survey of recent college graduates to test the overall mediation model. Although the model was supported, the relationship between objective overqualification and job satisfaction was not significant, raising the question of whether the hypothesized predictive relationship between perceived overqualification and job satisfaction is reversed. Study 2 tested directionality in the relationship between perceived overqualification and job satisfaction using a three-wave longitudinal panel design in a sample of full-time university staff employees. Results indicated that job dissatisfaction predicts subsequent perceived overqualification rather than the reverse

Hysteretic behavior of bladder afferent neurons in response to changes in bladder pressure

Abstract Background Mechanosensitive afferents innervating the bladder increase their firing rate as the bladder fills and pressure rises. However, the relationship between afferent firing rates and intravesical pressure is not a simple linear one. Firing rate responses to pressure can differ depending on prior activity, demonstrating hysteresis in the system. Though this hysteresis has been commented on in published literature, it has not been quantified. Results Sixty-six bladder afferents recorded from sacral dorsal root ganglia in five alpha-chloralose anesthetized felines were identified based on their characteristic responses to pressure (correlation coefficient ≥ 0.2) during saline infusion (2 ml/min). For saline infusion trials, we calculated a maximum hysteresis ratio between the firing rate difference at each pressure and the overall firing rate range (or Hmax) of 0.86 ± 0.09 (mean ± standard deviation) and mean hysteresis ratio (or Hmean) of 0.52 ± 0.13 (n = 46 afferents). For isovolumetric trials in two experiments (n = 33 afferents) Hmax was 0.72 ± 0.14 and Hmean was 0.40 ± 0.14. Conclusions A comprehensive state model that integrates these hysteresis parameters to determine the bladder state may improve upon existing neuroprostheses for bladder control.http://deepblue.lib.umich.edu/bitstream/2027.42/134628/1/12868_2016_Article_292.pd

Inflammation and salt in young adults: the African-PREDICT study

Purpose: Low-grade inflammation and a diet high in salt are both established risk factors for cardiovascular disease. High potassium (K+) intake was found to counter increase in blood pressure due to high salt intake and may potentially also have protective anti-inflammatory effects. To better understand these interactions under normal physiological conditions, we investigated the relationships between 22 inflammatory mediators with 24-h urinary K+ in young healthy adults stratified by low, medium and high salt intake (salt tertiles). We stratified by ethnicity due to potential salt sensitivity in black populations. Methods: In 991 healthy black (N = 457) and white (N = 534) adults, aged 20–30 years, with complete data for 24-h urinary sodium and K+, we analysed blood samples for 22 inflammatory mediators. Results: We found no differences in inflammatory mediators between low-, mid- and high-sodium tertiles in either the black or white groups. In multivariable-adjusted regression analyses in white adults, we found only in the lowest salt tertile that K+ associated negatively with pro-inflammatory mediators, namely interferon gamma, interleukin (IL) -7, IL-12, IL-17A, IL-23 and tumour necrosis factor alpha (all p ≤ 0.046). In the black population, we found no independent associations between K+ and any inflammatory mediator. Conclusion: In healthy white adults, 24-h urinary K+ associated independently and negatively with specific pro-inflammatory mediators, but only in those with a daily salt intake less than 6.31 g, suggesting K+ to play a protective, anti-inflammatory role in a low-sodium environment. No similar associations were found in young healthy black adults

Probabilistic Bisimulation: Naturally on Distributions

In contrast to the usual understanding of probabilistic systems as stochastic processes, recently these systems have also been regarded as transformers of probabilities. In this paper, we give a natural definition of strong bisimulation for probabilistic systems corresponding to this view that treats probability distributions as first-class citizens. Our definition applies in the same way to discrete systems as well as to systems with uncountable state and action spaces. Several examples demonstrate that our definition refines the understanding of behavioural equivalences of probabilistic systems. In particular, it solves a long-standing open problem concerning the representation of memoryless continuous time by memory-full continuous time. Finally, we give algorithms for computing this bisimulation not only for finite but also for classes of uncountably infinite systems

Statistical Physics of Fracture Surfaces Morphology

Experiments on fracture surface morphologies offer increasing amounts of data that can be analyzed using methods of statistical physics. One finds scaling exponents associated with correlation and structure functions, indicating a rich phenomenology of anomalous scaling. We argue that traditional models of fracture fail to reproduce this rich phenomenology and new ideas and concepts are called for. We present some recent models that introduce the effects of deviations from homogeneous linear elasticity theory on the morphology of fracture surfaces, succeeding to reproduce the multiscaling phenomenology at least in 1+1 dimensions. For surfaces in 2+1 dimensions we introduce novel methods of analysis based on projecting the data on the irreducible representations of the SO(2) symmetry group. It appears that this approach organizes effectively the rich scaling properties. We end up with the proposition of new experiments in which the rotational symmetry is not broken, such that the scaling properties should be particularly simple.Comment: A review paper submitted to J. Stat. Phy