Attuned to the Everyday: A Conversation with Veena Das

In May 2017, Veena Das joined the second edition of «Anthro-pology Talks» at the University of Bern. Every two years, the Institute of Social Anthropology invites leading social and cultural anthropologists to discuss their recent work. After a series of lectures and workshops, the event concludes with an interview about the visiting scholar’s work and their thoughts on the future of our discipline.In May 2017, Veena Das joined the second edition of «Anthro-pology Talks» at the University of Bern. Every two years, the Institute of Social Anthropology invites leading social and cultural anthropologists to discuss their recent work. After a series of lectures and workshops, the event concludes with an interview about the visiting scholar’s work and their thoughts on the future of our discipline.In May 2017, Veena Das joined the second edition of «Anthro-pology Talks» at the University of Bern. Every two years, the Institute of Social Anthropology invites leading social and cultural anthropologists to discuss their recent work. After a series of lectures and workshops, the event concludes with an interview about the visiting scholar’s work and their thoughts on the future of our discipline

Mapping the Space of Chemical Reactions Using Attention-Based Neural Networks

Organic reactions are usually assigned to classes containing reactions with similar reagents and mechanisms. Reaction classes facilitate the communication of complex concepts and efficient navigation through chemical reaction space. However, the classification process is a tedious task. It requires the identification of the corresponding reaction class template via annotation of the number of molecules in the reactions, the reaction center, and the distinction between reactants and reagents. This work shows that transformer-based models can infer reaction classes from non-annotated, simple text-based representations of chemical reactions. Our best model reaches a classification accuracy of 98.2%. We also show that the learned representations can be used as reaction fingerprints that capture fine-grained differences between reaction classes better than traditional reaction fingerprints. The insights into chemical reaction space enabled by our learned fingerprints are illustrated by an interactive reaction atlas providing visual clustering and similarity searching.Comment: https://rxn4chemistry.github.io/rxnfp

Distributed Disdrometer and Rain Gauge Measurement Infrastructure Developed for GPM Ground Validation

Global Precipitation Mission (GPM)retrieval algorithm validation requires datasets characterizing the 4-D structure, variability, and correlation properties of hydrometeor particle size distributions (PSD) and accumulations over satellite fields of view (FOV;<10 km). Collection of this data provides a means to assess retrieval errors related to beam filling and algorithm PSD assumptions. Hence, GPM Ground Validation is developing a deployable network of precipitation gauges and disdrometers to provide fine-scale measurements of PSD and precipitation accumulation variability. These observations will be combined with dual-frequency, polarimetric, and profiling radar data in a bootstrapping fashion to extend validated PSD measurements to a large coverage domain. Accordingly, a total of 24 Parsivel disdrometers(PD), 5 3rd-generation 2D Video Disdrometers (2DVD), 70 tipping bucket rain gauges (TBRG),9 weighing gauges, 7 Hot-Plate precipitation sensors (HP), and 3 Micro Rain Radars (MRR) have been procured. In liquid precipitation the suite of TBRG, PD and 2DVD instruments will quantify a broad spectrum of rain rate and PSD variability at sub-kilometer scales. In the envisioned network configuration 5 2DVDs will act as reference points for 16 collocated PD and TBRG measurements. We find that PD measurements provide similar measures of the rain PSD as observed with collocated 2DVDs (e.g., D0, Nw) for rain rates less than 15 mm/hr. For heavier rain rates we will rely on 2DVDs for PSD information. For snowfall we will combine point-redundant observations of SWER distributed over three or more locations within a FOV. Each location will contain at least one fenced weighing gauge, one HP, two PDs, and a 2DVD. MRRs will also be located at each site to extend the measurement to the column. By collecting SWER measurements using different instrument types that employ different measurement techniques our objective is to separate measurement uncertainty from natural variability in SWER and PSD. As demonstrated using C3VP polarimetric radar, gauge, and 2DVD/PD datasets these measurements can be combined to bootstrap an area wide SWER estimate via constrained modification of density-diameter and radar reflectivity-snowfall relationships. These data will be combined with snowpack, airborne microphysics, radar, radiometer, and tropospheric sounding data to refine GPM snowfall retrievals. The gauge and disdrometer instruments are being developed to operate autonomously when necessary using solar power and wireless communications. These systems will be deployed in numerous field campaigns through 2016. Planned deployment of these systems include field campaigns in Finland (2010), Oklahoma (2011), Canada (2012) and North Carolina (2013). GPM will also deploy 20 pairs of TBRGs within a 25 km2 region along the Virginia coast under NASA NPOL radar coverage in order to quantify errors in point-area rainfall measurements

Subcellular structural plasticity caused by the absence of the fast Ca²⁺ buffer calbindin D-28k in recurrent collaterals of cerebellar Purkinje neurons

Purkinje cells (PC) control spike timing of neighboring PC by their recurrent axon collaterals. These synapses underlie fast cerebellar oscillations and are characterized by a strong facilitation within a time window of i transients were previously shown to be bigger in PC boutons of young (second postnatal week) CB-/- mice, yet IPSC mean amplitudes remained unaltered in connected CB–/– PC. Since PC spine morphology is altered in adult CB–/– mice (longer necks, larger spine head volume), we summoned that morphological compensation/adaptation mechanisms might also be induced in CB–/– PC axon collaterals including boutons. In these mice, biocytin-filled PC reconstructions revealed that the number of axonal varicosities per PC axon collateral was augmented, mostly confined to the granule cell layer. Additionally, the volume of individual boutons was increased, evidenced from z-stacks of confocal images. EM analysis of PC–PC synapses revealed an enhancement in active zone (AZ) length by approximately 23%, paralleled by a higher number of docked vesicles per AZ in CB–/– boutons. Moreover, synaptic cleft width was larger in CB–/– (23.8 ± 0.43 nm) compared to wild type (21.17 ± 0.39 nm) synapses. We propose that the morphological changes, i.e., the larger bouton volume, the enhanced AZ length and the higher number of docked vesicles, in combination with the increase in synaptic cleft width likely modifies the GABA release properties at this synapse in CB–/– mice. We view these changes as adaptation/homeostatic mechanisms to likely maintain characteristics of synaptic transmission in the absence of the fast Ca²⁺ buffer CB. Our study provides further evidence on the functioning of the Ca²⁺ homeostasome

Comparison of Disdrometer and Rain Gauge Measurements During Pre-CHUVA

Cloud processes of the main precipitation systems in Brazil: A contribution to cloud resolving modeling and to the global precipitation measurement

Long-term data for endemic frog genera reveal potential conservation crisis in the Bale Mountains, Ethiopia

Populations of many frogs have declined alarmingly in recent years, placing nearly one third of the \u3e 6,000 species under threat of extinction. Declines have been attributed largely to habitat loss, environmental degradation and/or infectious diseases such as chytridiomycosis. Many frogs undergo dramatic natural population fluctuations such that long-term data are required to determine population trends without undue influence of stochastic factors. We present long-term quantitative data (individuals encountered per person hour of searching) for four monotypic frog genera endemic to an Afromontane region of exceptional importance but growing conservation concern: one endemic to the Ethiopian highlands (Spinophrynoides osgoodi) and three endemic to the Bale Mountains (Altiphrynoides malcolmi, Balebreviceps hillmani, Ericabatrachus baleensis), collected during 15 field trips to the Bale Mountains between 1971 and 2009. Only a single confirmed sighting of S. osgoodi has been made since 1995. The other three species have also declined, at least locally. E. baleensis appears to have been extirpated at its type locality and at the same site B. hillmani has declined. These declines are in association with substantial habitat degradation caused by a growing human population. Chytrid fungus has been found on several frog species in Bale, although no dead or moribund frogs have been encountered. These results expose an urgent need for more amphibian surveys in the Bale Mountains. Additionally, we argue that detrimental human exploitation must be halted immediately in at least some parts of the Harenna Forest if a conservation crisis is to be averted

Characterization and potential roles of calretinin in rodent spermatozoa

Calretinin has been detected in various excitable cells but the presence and putative roles of such a calcium-binding protein has never been characterized in sperm.Epididymal spermatozoa were collected from C57Bl6 (wild-type, WT) or calretinin knockout (CR−/−) mice and Wistar rats. A specific staining for calretinin was detected by immunofluorescence in the principal piece of the flagellum, both in WT mouse and rat spermatozoa. Western blots confirmed the expression of calretinin in rat and WT spermatozoa as well as its absence in CR−/− mice.No significant difference was observed in the spontaneous acrosome reaction between WT and CR−/− sperm. The addition of the calcium-ionophore A-23187, Thapsigargin or Progesterone to WT or CR−/− incubated spermatozoa induced increases in the acrosome reaction but the stimulatory effects were identical in both genotypes. Motility measurements assessed by computer-assisted sperm analysis indicated that, under basal non-stimulatory conditions, CR-/- sperm exhibited a lower curvilinear velocity and a smaller lateral head movement amplitude, although no difference was observed for the beat cross frequency. After incubation with 25 mM NH4Cl, the curvilinear velocity, the amplitude of the lateral head movement and the hyperactivation were increased, while the beat cross frequency was decreased, in both genotypes.Evaluation of the in vivo fertility potential indicated that the CR−/− litter sizes were clearly reduced compared to the WT litter sizes.Our study describes, for the first time, the expression of calretinin in sperm. These data extend the potential implication of calcium-binding proteins in the sperm calcium-signaling cascade and bring new insights into the understanding of sperm physiology

High Prevalence of the Amphibian Chytrid Fungus (\u3cem\u3eBatrachochytrium dendrobatidis\u3c/em\u3e) across Multiple Taxa and Localities in the Highlands of Ethiopia

Surveys of the potentially lethal amphibian chytrid fungus (Batrachochytrium dendrobatidis - Bd) in Africa are patchy, especially in some regions of high species endemicity. We present results of the first Bd surveys of wild amphibians in Ethiopia, for two upland regions on either side of the Rift Valley: the Bale Mountains and the Kaffa region. Surveys were opportunistic so that robust interpretation of the data is limited. Utilizing diagnostic qPCR assays, 51 out of 120 frogs (14 species in 10 genera) tested positive for Bd at altitudes of 1,620–3,225 m, across all genera and species, and all but two localities. Prevalence was not significantly different between the two regions or two years (2008, 2009) sampled. Prevalence and parasite load was higher in species with aquatic tadpoles than those with terrestrial early life-history stages, but these differences were not significant. Impacts of Bd infection were not investigated, but no dead or dying frogs were found. This is the first report of Bd in Ethiopia, a country in which approximately 40% of its more than 60 species are endemic. Declines have occurred in some frog species in some localities in Ethiopia, and although habitat degradation is a likely cause in at least some places, further studies of Bd in Ethiopia are required to understand if it is a threat

Detecting gravitational waves from cosmological phase transitions with LISA: an update

We investigate the potential for observing gravitational waves from cosmological phase transitions with LISA in light of recent theoretical and experimental developments. Our analysis is based on current state-of-the-art simulations of sound waves in the cosmic fluid after the phase transition completes. We discuss the various sources of gravitational radiation, the underlying parameters describing the phase transition and a variety of viable particle physics models in this context, clarifying common misconceptions that appear in the literature and identifying open questions requiring future study. We also present a web-based tool, PTPlot, that allows users to obtain up-to-date detection prospects for a given set of phase transition parameters at LISA.acceptedVersio