Fluid theory of coherent magnetic vortices in high-beta space plasmas

In-situ observations in the Earth's and Saturn's magnetosheaths and in the solar wind reveal the presence of Alfv\'en vortices as intermittent structures in the range of scales from fluid lengths down to few ion lengths. The density and the magnetic field associated with them appear to be compressible for higher plasma betas. Until now, only incompressible Alfv\'en vortices have been known. Motivated by space plasma observations we develop a new model of magnetic vortices in high-beta plasmas with anisotropic temperature, possessing compressible density and magnetic field, whose typical size ranges from fluid to ion scales. At magneto-fluid scales we find novel non-propagating field-aligned cylindrical monopoles and inclined propagating dipoles. Their transverse magnetic and velocity fluctuations are aligned, but not identical, {and they exhibit density and compressible magnetic field fluctuations $\delta n$ and $\delta B_\Vert$ localized inside the vortex core. In the presence of thermal anisotropy and acoustic effects, they may be correlated or anti-correlated $\delta n/\delta B_\Vert={\rm constant}\gtrless 0$; fluctuations whose velocity along the magnetic field is below the ion thermal speed are always correlated.} At ion or kinetic scales (with the smallest radii $\sim c/\omega_{pi}, \rho_{L i}$) {and in the absence of acoustic perturbations}, only dipolar Alfv\'en vortices survive with similar properties as those at fluid scales, except for their $\delta n/n_0$ that reaches the level of $\delta B_\Vert/B_0$. At kinetic scales we find also pressure balanced dipolar structures, possessing finite parallel electric field $E_\Vert$ and purely compressional magnetic field perturbation

Naturgeschichte von madagassischen Giftfröschen: Experimentale Analyse von Aposematismus, Kaulquappenmorphologie und Langlebigkeit

Poisonous frogs from genus Mantella belong to the Malagasy-Comoran endemic family Mantellidae and include about 17 species. Here, the tadpole morphology of nine species of Mantella is described and compared. The tadpole morphology of M. crocea/milotympanum-hybrids, M. madagascariensis, M. pulchra, M. viridis, M. baroni, M. bernhardi and M. betsileo is described for the first time. Species identification is difficult only by means of morphometric variables. Longevity of five species of Mantella (M. aurantiaca, M. baroni, M. bernhardi, M. crocea, M. madagascariensis) was examined applying skeletochronology. In 57% of the specimens, no lines of arrested growth (LAGs) were found, and the number of LAGs recognized in the remaining specimens ranged between zero and two. The effectiveness of aposematic colouration in Mantella was tested exposing clay frog models in three different colours to rainforest habitats in Madagascar. Predation observed on models was tested for correlation between colouration of models as a distinctive predictor of predation, time of predation (day, night), shape (frog, shapeless), position of the model and influence of predators’ experience. In addition, learning effect among the predators was studied. Most predictors showed not to be significant determinants of predation. Efficiency in predator deterring based on visual and olfactory cues was tested by feeding choice experiments, with several species of snakes caught in the field in Madagascar. Snakes were offered one Mantella and one edible frog at the same time, giving them the opportunity to choose. Snakes showed a strong preference for edible frogs over specimens of Mantella. I also compared predation rate on two types of frogs among “experienced” (caught in Mantella habitat) and naïve snakes (caught in areas not inhabited with Mantella) and found significant differences, with “experienced” snakes eating altogether only one Mantella frog.Die Giftfrösche aus der Gattung Mantella gehören in die auf Madagaskar und den Komoren endemische Familie der Mantellidae. Mantella umfasst 17 Arten. In dieser Arbeit wird die Kaulquappenmorphologie von neun dieser Arten beschrieben und verglichen. Dies umfasst einen M. crocea/milotympanum-Hybrid sowie die Arten M. madagascariensis, M. pulchra, M. viridis, M. baroni, M. bernhardi und M. betsileo, die in dieser Arbeit erstmalig beschrieben werden.. Eine Bestimmung der Arten anhand morphometrischer Daten ist schwierig. Die Langlebigkeit von fünf Mantella-Arten wurde mithilfe von Skeletochronologie untersucht (M. aurantiaca, M. baroni, M. bernhardi, M. crocea, M. madagascariensis). In 57 % der analysierten Proben, fanden sich keine Jahresringe, die verbleibenden Proben wiesen ein bis zwei Jahresringe auf. Die Effektivität von aposematischer Färbung bei Vertretern dieser Gattung wurde mithilfe von entsprechend gefärbten Knetfroschmodellen in einer Feldstudie in Madagaskar untersucht. Die Faktoren Farbe, Prädationszeit (Tag, Nacht), Form (Froschform, formlos), Position der Modelle und Erfahrung der Prädatoren wurden auf ihren Einfluss auf die Häufigkeit der Prädationsereignisse getestet. Ebenso wurden Untersuchungen zum Lerneffekt bei Prädatoren durchgeführt. Für die meisten der Faktoren konnte kein signifikanter Einfluss festgestellt werden. Die Effizienz der Prädatorenabschreckung durch visuelle und olfaktorische Hinweise von Mantella wurde in Fraßexperimenten mit wildgefangenen Schlangen in Madagaskar durchgeführt. Den Schlangen wurden gleichzeitig ein auffällig gefärbter Mantella und ein essbarer, unscheinbar gefärbter Frosch zur Auswahl angeboten. Die Schlangen zeigten eine deutliche Präferenz für die Frösche ohne Warnfärbung. Dieser Effekt war umso stärker, wenn es sich um Schlangen handelte, bei denen aufgrund ihres Fundortes davon ausgegangen werden kann, dass sie bereits Erfahrung mit Mantella hatten

Management, Diagnostic and Prognostic Significance of Acetylcholinesterase as a Biomarker of the Toxic Effects of Pesticides in People Occupationally Exposed

AIM: The paper presents research on the most common causes of exposure that leads to disorders of cholinesterase activity, as well as an overview of the results of cholinesterase activity with the poisoned people.MATERIAL AND METHODS: In a group of 35 acute poisoned patients by organophosphate compounds has led to inhibition of AchE. A total number of examined workers are 175 in the chemical industry and agricultural production in the area of Rasina District-Serbia.RESULTS: The results showed that among workers who are constantly exposed to pesticides, acetylcholinesterase is within the reference value. Having examined the medical records of these workers, it is noted that, at 72%, there is a slight fall of AchE activity, each year. The workers who had been exposed to pesticides at the time of testing had acetylcholinesterase regarding reference value, but 52% of them had a few years ago significantly reduced the value of the activity of acetylcholinesterase, which was treated and then transferred to other jobs. The 48% of these workers had acetylcholinesterase regarding benchmarks or were transferred to other jobs, for a variety of other health problems.CONCLUSION: Using each pesticide should only deal with people who are well versed in the way of its use, as well as the way of protecting them from poisoning

Functional genomics of abiotic environmental adaptation in lacertid lizards and other vertebrates

Understanding the genomic basis of adaptation to different abiotic environments is important in the context of climate change and resulting short-term environmental fluctuations. Using functional and comparative genomics approaches, we here investigated whether signatures of genomic adaptation to a set of environmental parameters are concentrated in specific subsets of genes and functions in lacertid lizards and other vertebrates. We first identify 200 genes with signatures of positive diversifying selection from transcriptomes of 24 species of lacertid lizards and demonstrate their involvement in physiological and morphological adaptations to climate. To understand how functionally similar these genes are to previously predicted candidate functions for climate adaptation and to compare them with other vertebrate species, we then performed a meta-analysis of 1,100 genes under selection obtained from -omics studies in vertebrate species adapted to different abiotic factors. We found that the vertebrate gene set formed a tightly connected interactome, which was to 23% enriched in previously predicted functions of adaptation to climate, and to a large part (18%) involved in organismal stress response. We found a much higher degree of identical genes being repeatedly selected among different animal groups (43.6%), and of functional similarity and post-translational modifications than expected by chance, and no clear functional division between genes used for ectotherm and endotherm physiological strategies. In total, 171 out of 200 genes of Lacertidae were part of this network. These results highlight an important role of a comparatively small set of genes and their functions in environmental adaptation and narrow the set of candidate pathways and markers to be used in future research on adaptation and stress response related to climate change

Depression and suicidality among psychiatric residents - results from a multi-country study

Background Previous studies have highlighted risks for depression and suicide in medical cohorts, but evidence regarding psychiatric residents is missing. This study aimed to determine rates of depression, suicide ideation and suicide attempt among psychiatric residents and to identify associated individual, educational and work-related risk factors. Methods A total of 1980 residents from 22 countries completed the online survey which collected data on depression (PHQ-9), suicidality (SIBQ), socio-demographic profiles, training, and education. Generalized linear modeling and logistic regression analysis were used to predict depression and suicide ideation, respectively. Results The vast majority of residents did not report depression, suicide ideation or attempting suicide during psychiatric training. Approximately 15% (n=280) of residents met criteria for depression, 12.3% (n=225) reported active suicide ideation, and 0.7% (n=12) attempted suicide during the training. Long working hours and no clinical supervision were associated with depression, while more completed years of training and lack of other postgraduate education (e.g. PhD or psychotherapy training) were associated with increased risk for suicide ideation during psychiatric training. Being single and female was associated with worse mental health during training. Limitations Due to the cross-sectional nature of the study, results should be confirmed by longitudinal studies. Response rate was variable but the outcome variables did not statistically significantly differ between countries with response rates of more or less than 50%. Conclusion Depression rates among psychiatric residents in this study were lower than previously reported data, while suicide ideation rates were similar to previous reports. Poor working and training conditions were associated with worse outcomes. Training programmes should include effective help for residents experiencing mental health problems so that they could progress through their career to the benefit of their patients and wider society

Advances in multiangle satellite remote sensing of speciated airborne particulate matter and association with adverse health effects: from MISR to MAIA

Inhalation of airborne particulate matter (PM) is associated with a variety of adverse health outcomes. However, the relative toxicity of specific PM types—mixtures of particles of varying sizes, shapes, and chemical compositions—is not well understood. A major impediment has been the sparse distribution of surface sensors, especially those measuring speciated PM. Aerosol remote sensing from Earth orbit offers the opportunity to improve our understanding of the health risks associated with different particle types and sources. The Multi-angle Imaging SpectroRadiometer (MISR) instrument aboard NASA’s Terra satellite has demonstrated the value of near-simultaneous observations of backscattered sunlight from multiple view angles for remote sensing of aerosol abundances and particle properties over land. The Multi-Angle Imager for Aerosols (MAIA) instrument, currently in development, improves on MISR’s sensitivity to airborne particle composition by incorporating polarimetry and expanded spectral range. Spatiotemporal regression relationships generated using collocated surface monitor and chemical transport model data will be used to convert fractional aerosol optical depths retrieved from MAIA observations to near-surface PM_(10), PM_(2.5), and speciated PM_(2.5). Health scientists on the MAIA team will use the resulting exposure estimates over globally distributed target areas to investigate the association of particle species with population health effects

NUDT2 Disruption Elevates Diadenosine Tetraphosphate (Ap4A) and Down-Regulates Immune Response and Cancer Promotion Genes.

Regulation of gene expression is one of several roles proposed for the stress-induced nucleotide diadenosine tetraphosphate (Ap4A). We have examined this directly by a comparative RNA-Seq analysis of KBM-7 chronic myelogenous leukemia cells and KBM-7 cells in which the NUDT2 Ap4A hydrolase gene had been disrupted (NuKO cells), causing a 175-fold increase in intracellular Ap4A. 6,288 differentially expressed genes were identified with P < 0.05. Of these, 980 were up-regulated and 705 down-regulated in NuKO cells with a fold-change ≥ 2. Ingenuity® Pathway Analysis (IPA®) was used to assign these genes to known canonical pathways and functional networks. Pathways associated with interferon responses, pattern recognition receptors and inflammation scored highly in the down-regulated set of genes while functions associated with MHC class II antigens were prominent among the up-regulated genes, which otherwise showed little organization into major functional gene sets. Tryptophan catabolism was also strongly down-regulated as were numerous genes known to be involved in tumor promotion in other systems, with roles in the epithelial-mesenchymal transition, proliferation, invasion and metastasis. Conversely, some pro-apoptotic genes were up-regulated. Major upstream factors predicted by IPA® for gene down-regulation included NFκB, STAT1/2, IRF3/4 and SP1 but no major factors controlling gene up-regulation were identified. Potential mechanisms for gene regulation mediated by Ap4A and/or NUDT2 disruption include binding of Ap4A to the HINT1 co-repressor, autocrine activation of purinoceptors by Ap4A, chromatin remodeling, effects of NUDT2 loss on transcript stability, and inhibition of ATP-dependent regulatory factors such as protein kinases by Ap4A. Existing evidence favors the last of these as the most probable mechanism. Regardless, our results suggest that the NUDT2 protein could be a novel cancer chemotherapeutic target, with its inhibition potentially exerting strong anti-tumor effects via multiple pathways involving metastasis, invasion, immunosuppression and apoptosis

Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points