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The Hunga volcano violently erupted on 15 January 2022, producing the largest perturbation of the stratospheric aerosol layer since Pinatubo 1991, despite the initially estimated modest injection of SO2. This study presents novel SO2 and sulfate aerosol (SA) co‐retrievals from the Infrared Atmospheric Sounding Interferometer, and uses them to quantify the initial progression of the Hunga plume. These observations are consistent with rapid conversion of SO2 (e‐folding time: 17.1 ± 4.3 days) to SA, with an injected burden of >1.0 Tg SO2. This points at larger SO2 injections than previously thought. A long‐lasting SA plume was observed, with two separate build‐up phases, and with a meridional dispersion of marked anomalies from the tropics to the higher southern hemispheric latitudes. A limited (∼20%) SA removal was observed after 1‐year dispersion. The total injected SA mass burden was estimated at 1.6 ± 0.5 Tg in the total atmospheric column, with a build‐up e‐folding time of about 2 months. Plain Language Summary: The eruption of the submarine Hunga volcano in January 2022 polluted the global stratosphere with a large amount of water vapor and significantly perturbed the stratospheric aerosol layer. In this paper, we present a 1‐year long aftermath study of the stratospheric sulfur pollution from this volcanic eruption using observations from the Infrared Atmospheric Sounding Interferometer (IASI) satellite‐borne instrument. Gaseous and aerosol sulfur emissions are observed simultaneously using the specific potential of this sensor. These observations provide unique capabilities to characterize the aerosol type in the Hunga plume and the sulfur cycle associated with the volcanic emissions. An extremely rapid conversion of gaseous sulfur emissions to aerosols is observed, leading to larger than expected and persistent anomalies of the stratospheric aerosol layer (compared with a consistent long‐term climatology), still noticeable in the Southern Hemisphere after 1 year. The total mass of the emitted sulfur in gas and aerosol state is also simultaneously estimated, for the first time. Key Points: Novel co‐retrieval of SO2 and sulfate aerosol from Infrared Atmospheric Sounding Interferometer (IASI) used to study the dispersion of the Hunga plume over the entire year 2022Rapid conversion of SO2 (2 weeks e‐folding time) and long‐lasting sulfate aerosol observedLarger SO2 injected mass burden (>1.0 Tg) than previously thought and a large sulfate aerosol total burden (1.6 Tg) estimated [ABSTRACT FROM AUTHOR]

Occupancy models were originally developed to better understand species distribution while accounting for imperfect detection. Because species distribution is not only shaped by habitat quality but also by the ability of individuals to reach suitable habitats, spatial dynamic occupancy models have been proposed to extend the original framework by defining that site colonisation was a function of the Euclidean distance to occupied sites. However, not all sites in the landscape are equally accessible due to the presence of barriers, that of corridors, etc. To account for connectivity between sites, the Euclidean distance has recently been replaced by a least‐cost path distance, which explicitly accounts for landscape resistance, but assumes that individuals will follow the optimal route.To relax this assumption, we first developed a new spatial occupancy model that incorporates commute‐time distance derived from circuit theory to model accessibility across sites. This distance has the advantage of modelling movement as a random walk and accounting for the fact that colonisation could be achieved from multiple paths. Our approach allows for the explicit estimation of landscape connectivity from detection/non‐detection data and a direct measure of connectivity uncertainty.We implemented the model in the Bayesian framework using the nimble R package, which allows useful R connectivity functions to be called from within the model. Second, we carried out a simulation study to assess the performance of our model by considering four scenarios depicting an increasing level of landscape resistance. Third, to illustrate our new approach, we studied the recolonisation of two carnivores in France.We quantified the degree to which rivers facilitate Eurasian otter (Lutra lutra) colonisation and highways impede Eurasian lynx (Lynx lynx) colonisation. Overall, spatial occupancy models provide a flexible framework to accommodate any distance metric designed to align with species dispersal ecology. [ABSTRACT FROM AUTHOR]

The role of antiviral treatment in coronavirus disease 2019 hospitalized patients is controversial. To address this question, we analyzed simultaneously nasopharyngeal viral load and the National Early Warning Score 2 (NEWS‐2) using an effect compartment model to relate viral dynamics and the evolution of clinical severity. The model is applied to 664 hospitalized patients included in the DisCoVeRy trial (NCT04315948; EudraCT 2020‐000936‐23) randomly assigned to either standard of care (SoC) or SoC + remdesivir. Then we use the model to simulate the impact of antiviral treatments on the time to clinical improvement, defined by a NEWS‐2 score lower than 3 (in patients with NEWS‐2 <7 at hospitalization) or 5 (in patients with NEWS‐2 ≥7 at hospitalization), distinguishing between patients with low or high viral load at hospitalization. The model can fit well the different observed patients trajectories, showing that clinical evolution is associated with viral dynamics, albeit with large interindividual variability. Remdesivir antiviral activity was 22% and 78% in patients with low or high viral loads, respectively, which is not sufficient to generate a meaningful effect on NEWS‐2. However, simulations predicted that antiviral activity greater than 99% could reduce by 2 days the time to clinical improvement in patients with high viral load, irrespective of the NEWS‐2 score at hospitalization, whereas no meaningful effect was predicted in patients with low viral loads. Our results demonstrate that time to clinical improvement is associated with time to viral clearance and that highly effective antiviral drugs could hasten clinical improvement in hospitalized patients with high viral loads. [ABSTRACT FROM AUTHOR]

Insolation is the engine of monsoon and Walker circulations over the tropical Indian Ocean. Here, we present Holocene coccolith‐related net primary productivity (NPP) signals from two sediment cores retrieved in the wind‐driven coastal upwelling systems off southern India and southern Sumatra. Upwelling‐induced NPP is enhanced during summer and autumn and is a powerful tool to reconstruct atmospheric features at a seasonal scale. Our records indicate that during summer and autumn, westerly winds off southern India strengthened from the early‐Holocene (EH) to late‐Holocene (LH), while southeasterly winds off southern Sumatra strengthened from the EH to mid‐Holocene (MH) and weakened from the MH to LH. Comparisons with previous paleoclimate records and simulations, allow us to confirm such wind patterns at a regional scale and identify distinct atmospheric features associated to insolation before and after the MH. From the EH to MH, as the insolation in the Northern Hemisphere weakens during summer and strengthens during autumn, the equatorial Indian Ocean is characterized by more vigorous Walker and monsoon circulations in summer and autumn, respectively. From the MH to LH, as the insolation weakens in the Northern Hemisphere during summer and over the equator during autumn, the equatorial Indian Ocean is influenced by a general reinforcement of the Walker circulation during both seasons, a feature that we relate to a modern negative IOD‐like mode. The changes in wind result in increasing precipitation over Indonesia and India from EH to MH and over Indonesia from MH to LH as India is getting dryer. Plain Language Summary: The aim of this study is to examine how monsoon and Walker circulations from the tropical Indian Ocean responded to changing insolation over the Holocene. Understanding their dynamics under varying boundary conditions is important for predicting future climate, as they shape precipitation of a region that sustains billions of people. First, we focus on reconstructing changes in seasonal surface wind intensity, based on net coccolith‐related primary productivity signal from two sediment cores retrieved in the coastal upwelling systems off southern India and off southern Sumatra. When these upwellings occur during summer and autumn, nutrient‐rich deep waters surface and enhance the primary productivity. Second, we use paleoclimate records and simulations to provide broad‐scale atmospheric changes and test our assumptions. Our results show that westerly winds off southern India strengthened from early to late Holocene, while southeasterly winds off southern Sumatra strengthened from early to mid‐Holocene and weakened from mid to late Holocene, thus implying distinct wind and precipitation dynamics patterns before and after mid‐Holocene. These features appear to result in weaker and stronger precipitation over Africa and Indonesia from early‐ to mid‐Holocene, respectively, and in a precipitation maximum over India during the mid‐Holocene. Key Points: Stronger zonal Walker circulation during summer from early‐ to late‐HoloceneStronger meridional monsoon circulation during autumn from early‐ to mid‐HoloceneStronger (weaker) precipitation over Indonesia (Africa) from early‐ to mid‐Holocene and precipitation maximum over India in mid‐Holocene [ABSTRACT FROM AUTHOR]

The Tonga eruption of 15 January 2022 has released a long‐lived stratospheric plume of sulfate aerosols. More than 17 months after, we focus on the high quality data series of SAGE III (Stratospheric Aerosol and Gas Experiment) on board the International Space Station (ISS) to determine the mean radius and size distribution of the aerosols and their total mass. The persisting volcanic aerosols—with a mode width of 1.25 and an effective radius of 0.4 μm—differ from the significantly smaller background aerosols and from those measured during recent stratospheric eruptions. The sulfuric acid mass between 50°S and 30°N is estimated to be very stable in spite of considerable redistribution in latitude at a value of 0.66 ± 0.1 Tg, corresponding to an initial sulfur dioxide emission of 0.44 Tg. Such properties are expected to facilitate the persistence of a climate warming due to the volcanic water vapor. Plain Language Summary: We study the stratospheric aerosol plume produced by the Hunga Tonga–Hunga Ha'apai eruption on 15 January 2022 based on the high quality solar occultation measurements of the instrument SAGE III (Stratospheric Aerosol and Gas Experiment) onboard the International Space Station. These data reveal that the aerosol sizes are about twice as large as after other documented volcanic eruptions and that the total mass of H2SO4 in the liquid droplets of sulfate in the stratosphere has been very stable from March 2022, when it started to be well homogeneized in longitude, to November 2022, when it started to decay. The total mass of 0.66 Tg of H2SO4 is in good agreement with the early estimates of a stratospheric emission of 0.4–0.5 Tg of SO2. The implication is that the aerosol radiative impact will not mask the persisting warming effect of the water vapor injected in the stratosphere by the eruption. Key Points: The extinction of the stratospheric plume of the 2022 Tonga eruption is well modeled by a unimodal distribution of sulfate particlesThe effective radius of the aerosols is large with values close to 0.4 μm, and a mode width of 1.25, from March 2022 to June 2023We estimate a total H2SO4 mass in stratospheric sulfate aerosols of about 0.66 corresponding to 0.44 Tg of SO2 initially injected [ABSTRACT FROM AUTHOR]

The emergence and sustained transmission of novel pathogens are exerting an increasing demand on the diagnostics sector worldwide, as seen with the ongoing severe acute respiratory coronavirus 2 (SARS‐CoV‐2) pandemic and the more recent public health concern of monkeypox virus (MPXV) since May 2022. Appropriate and reliable viral inactivation measures are needed to ensure the safety of personnel handling these infectious samples. In the present study, seven commercialized diagnosis buffers, heat (56°C and 60°C), and sodium dodecyl sulfate detergent (2.0%, 1.0%, and 0.5% final concentrations) were tested against infectious SARS‐CoV‐2 and MPXV culture isolates on Vero cell culture. Cytopathic effects were observed up to 7 days postinoculation and viral load evolution was measured by semiquantitative polymerase chain reaction. The World Health Organization recommends an infectious titer reduction of at least 4 log10. As such, the data show efficacious SARS‐CoV‐2 inactivation by all investigated methods, with >6.0 log10 reduction. MPXV inactivation was also validated with all investigated methods with 6.9 log10 reductions, although some commercial buffers required a longer incubation period to yield complete inactivation. These results are valuable for facilities, notably those without biosafety level‐3 capabilities, that need to implement rapid and reliable protocols common against both SARS‐CoV‐2 and MPXV. [ABSTRACT FROM AUTHOR]

The Arabian Sea (AS) is one of the most productive oceanic regions in the world due to several monsoon‐related processes that can increase nutrients contents in the euphotic zone. Previous studies of the imprint of oceanic primary productivity (PP) in AS sediments yielded diverse results depending on the studied area and the chosen proxies, with unprecise paleoclimatic interpretations. Here, we provide multi‐decennial PP and coastal upwelling dynamic records off northern Oman over the last 23 Kyr, based on the analysis of coccoliths from sediment core MD00‐2354. Our results have been compared with previous paleoenvironmental records as well as new modeling data to get precise paleoclimatic interpretations. We document higher PP and weaker coastal upwelling during the Last Glacial Maximum relative to the Holocene, and significant millennial‐scale variations over the last deglaciation corresponding to the fluctuations of the Atlantic Meridional Overturning Circulation strength. Higher PP and weaker upwelling are found during the cold stadials, while lower PP and stronger upwelling during the warm interstadial. We propose that the increases of PP were driven by increased bioavailable nutrient content in surface waters under both stronger winter monsoon conditions that strengthened the convective mixing, and higher aeolian inputs. Over the Holocene, stronger upwelling and slightly lower PP are found during the Early‐Mid Holocene, when higher summer insolation triggered stronger summer monsoon. At that time, the lower PP was probably the result of restricted advection of eutrophic summer upwelling seawater under negative wind stress curls and less aeolian inputs. Plain Language Summary: Ocean primary productivity (PP) is the production rate of organic carbon from inorganic carbon by ocean phytoplankton through photosynthesis, in which nutrients and sunlight are necessary. In tropical oceans, this rate is usually limited by the availability of nutrients in the sunlit ocean, which is controlled by physical processes such as seawater upward motion, ocean mixing, and dust storms. All these processes play a significant role in the northwestern Arabian Sea (AS) today. It is surrounded by arid lands that provide the highest amount of airborne material in the world and it is influenced by the Indian monsoon system that drives seawater upward motion and mixing in summer and winter, respectively. However, not much is known about their impact on PP in the past. This work aims to reconstruct changes of PP in the northwestern AS over the past twenty thousand years and understand by which process(es) they are impacted, based on a model‐data comparison approach. We have found that PP was higher during cold periods than during warm ones. The changes were mainly controlled by both, winter monsoon through changes in convective mixing, and dust storms through changes in nutrient‐enrich aeolian inputs. Key Points: Past primary productivity (PP) and upwelling in the NW Arabian Sea are reconstructed by coccolith assemblages from a marine sediment corePP was relatively high during the cold periods compared to the warm periods of the last 23 KyrPP changes were mainly controlled by winter monsoon through changes in convective mixing and by aeolian inputs [ABSTRACT FROM AUTHOR]

Following the Hunga Tonga eruption (20.6°S, 175.4°W, mid‐January 2022), we present a balloon‐borne characterization of the stratospheric aerosol plume one week after its injection (on 23 and 26 January 2022, La Réunion island at 21.1°S, 55.3°E). Satellite observations show that flight (a) took place during the overpass of a denser plume of sulfate aerosols (SA) compared to a more diluted plume during flight. (b) Observations show that the sampled plumes (at around 22, 25 and 19 km altitude, respectively) consist exclusively of very small particles (with radius <1 µm). Particles with radii between 0.5 and 1.0 µm show optically transparent features pointing to predominant SA. Particles with radii below 0.5 µm are partly absorbing, which could point to small sulfate coated ash particles, a feature not identified with space‐borne observations. This shows that in situ observations are necessary to fully characterize the microphysical properties of the plumes tracked by space‐borne instruments. Plain Language Summary: The Hunga Tonga‐Hunga Ha'apai volcano (at 20.6°S, 175.4°W) erupted on 13 and 15 January 2022 with injection of gases and aerosols up to 55 km altitude. Here, we present a study based on in situ aerosol observations on weather balloons on La Réunion (21.1°S, 55.3°E) within the injected Hunga Tonga aerosol plume one week after the eruption (23 and 26 January 2022). With respective satellite observations, we show that the first measurement flight took place during the overpass of a denser aerosol plume compared to the second flight. We find that the plume exhibits only small particles <1 μm, mainly consisting of sulfate aerosols (for particles between 0.5 and 1 μm in size) and an absorbing component for very small particles (<0.5 μm), possibly pointing to small ash particles coated by sulfur. This letter "absorbing" feature is a unique contribution brought by in situ measurements that fills a gap left by space‐borne instruments. Key Points: Predominant particle size range of <1 μm within the stratospheric aerosol plume of the Hunga Tonga eruptionOptically absorbing particles within the plume for particles <0.5 μm point to fractured, very small ash particlesMostly optically semi‐transparent particles, for particle sizes between 0.5 and 1.0 μm result from small sulfur coated ash particles [ABSTRACT FROM AUTHOR]

A comparison between two Dickson voltage multipliers realized in two technologies, fully depleted silicon on insulator (FDSOI) 28 nm and Bipolar CMOS (BiCMOS) 55 nm is presented. The assessment is based on the I–V characteristics measurements of transistors configured as diodes; and on the measurements of one and two stages of Dickson multipliers designed for RF energy harvesting. The I–V characteristics show that FDSOI technology is profitable owing to its smaller threshold voltage (Vth), and a leakage current less than that of BiCMOS. Consequently, for the same input voltage, the output voltage acquired in FDSOI is greater than that achieved with BiCMOS. Moreover, for rectifiers designed in FDSOI, a dynamic back gate bias could be employed to enhance the performance by adjusting dynamically the Vth and the leakage current. [ABSTRACT FROM AUTHOR]

High efficiency of charge–spin interconversion in spin Hall materials is a prime necessity to apprehend intriguing functionalities of spin–orbit torque for magnetization switching, auto‐oscillations, and domain wall motion in energy‐efficient and high‐speed spintronic devices. To this end, innovations in fabricating advanced materials that possess not only large charge–spin conversion efficiency but also viable electrical and spin Hall conductivity are of importance. Here, a new spin Hall material designed by implanting low energy 12 keV sulfur ions in heavy metal Pt, named as Pt(S), is reported that demonstrates eight times higher conversion efficiency as compared to pristine Pt. The figure of merit, spin Hall angle (θSH), up to θSHPt(S)of 0.502 together with considerable electrical conductivity σxxPt(S)of 1.65 × 106 Ω–1 m–1 is achieved. The spin Hall conductivityσSHPt(S) increases with increasing σxxPt(S), as σSHPt(S)∝σxxPt(S)1.7, implying an intrinsic mechanism in a dirty metal conduction regime. A comparatively large σSHPt(S) of 8.32 × 105 (ℏ2e) Ω–1 m–1 among the reported heavy‐metals‐based alloys can be useful for developing next‐generation spintronic devices using spin–orbit torque. [ABSTRACT FROM AUTHOR]

Obtaining estimates of animal population density is a key step in providing sound conservation and management strategies for wildlife. For many large carnivores however, estimating density is difficult because these species are elusive and wide‐ranging. Here, we focus on providing the first density estimates of the Eurasian lynx (Lynx lynx) in the French Jura and Vosges mountains. We sampled a total of 413 camera trapping sites (with two cameras per site) between January 2011 and April 2016 in seven study areas across seven counties of the French Jura and Vosges mountains. We obtained 592 lynx detections over 19,035 trap days in the Jura mountains and 0 detection over 6,804 trap days in the Vosges mountains. Based on coat patterns, we identified a total number of 92 unique individuals from photographs, including 16 females, 13 males, and 63 individuals of unknown sex. Using spatial capture–recapture (SCR) models, we estimated abundance in the study areas between 5 (SE = 0.1) and 29 (0.2) lynx and density between 0.24 (SE = 0.02) and 0.91 (SE = 0.03) lynx per 100 km2. We also provide a comparison with nonspatial density estimates and discuss the observed discrepancies. Our study is yet another example of the advantage of combining SCR methods and noninvasive sampling techniques to estimate density for elusive and wide‐ranging species, like large carnivores. While the estimated densities in the French Jura mountains are comparable to other lynx populations in Europe, the fact that we detected no lynx in the Vosges mountains is alarming. Connectivity should be encouraged between the French Jura mountains, the Vosges mountains, and the Palatinate Forest in Germany where a reintroduction program is currently ongoing. Our density estimates will help in setting a baseline conservation status for the lynx population in France. [ABSTRACT FROM AUTHOR]

The isolation, analysis, and enumeration of circulating tumor cells (CTCs) from cancer patient blood samples are a paradigm shift for cancer patient diagnosis, prognosis, and treatment monitoring. Most methods used to isolate and enumerate these target cells rely on the expression of cell surface markers, which varies between patients, cancer types, tumors, and stages. Here, we propose a label‐free high‐throughput platform to isolate, enumerate, and size CTCs on two coupled microfluidic devices. Cancer cells were purified through a Vortex chip and subsequently flowed in‐line to an impedance chip, where a pair of electrodes measured fluctuations of an applied electric field generated by cells passing through. A proof‐of‐concept of the coupling of those two devices was demonstrated with beads and cells. First, the impedance chip was tested as a stand‐alone device: (1) with beads (mean counting error of 1.0%, sizing information clearly separated three clusters for 8, 15, and 20 um beads, respectively) as well as (2) with cancer cells (mean counting error of 3.5%). Second, the combined setup was tested with beads, then with cells in phosphate‐buffered saline, and finally with cancer cells spiked in healthy blood. Experiments demonstrated that the Vortex HT chip enriched the cancer cells, which then could be counted and differentiated from smaller blood cells by the impedance chip based on size information. Further discrimination was shown with dual high‐frequency measurements using electric opacity, highlighting the potential application of this combined setup for a fully integrated label‐free isolation and enumeration of CTCs from cancer patient samples. © 2019 International Society for Advancement of Cytometry [ABSTRACT FROM AUTHOR]

Purified samples of Ho3N@C2(22010)‐C78 and Tb3N@C2(22010)‐C78 have been isolated by two distinct processes from the rich array of fullerenes and endohedral fullerenes present in carbon soot from graphite rods doped with Ho2O3 or Tb4O7. Crystallographic analysis of the endohedral fullerenes as cocrystals with Ni(OEP) (in which OEP is the dianion of octaethylporphyrin) shows that both molecules contain the chiral C2(22010)‐C78 cage. This cage does not obey the isolated pentagon rule (IPR) but has two sites where two pentagons share a common C−C bond. These pentalene units bind two of the metal ions, whereas the third metal resides near a hexagon of the cage. Inside the cages, the Ho3N or Tb3N unit is planar. Ho3N@C2(22010)‐C78 and Tb3N@C2(22010)‐C78 use the same cage previously found for Gd3N@C2(22010)‐C78 rather than the IPR‐obeying cage found in Sc3N@D3h‐C78. [ABSTRACT FROM AUTHOR]

The azafullerene Tb2@C79N is found to be a single‐molecule magnet with a high 100‐s blocking temperature of magnetization of 24 K and large coercivity. Tb magnetic moments with an easy‐axis single‐ion magnetic anisotropy are strongly coupled by the unpaired spin of the single‐electron Tb−Tb bond. Relaxation of magnetization in Tb2@C79N below 15 K proceeds via quantum tunneling of magnetization with the characteristic time τQTM=16 462±1230 s. At higher temperature, relaxation follows the Orbach mechanism with a barrier of 757±4 K, corresponding to the excited states, in which one of the Tb spins is flipped. New kids on the blocking: The azafullerene Tb2@C79N featuring a single‐electron Tb−Tb bond is found to be an air‐stable single‐molecule magnet with a high 100‐s blocking temperature of magnetization of 24 K and large coercivity. Tb magnetic moments with an easy‐axis single‐ion magnetic anisotropy are strongly coupled by the unpaired spin of the single‐electron Tb−Tb bond. [ABSTRACT FROM AUTHOR]

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Recently, Ruddlesden-Popper perovskites (RPPs) have attracted increasing interests due to their promising stability. However, the efficiency of solar cells based on RPPs is much lower than that based on 3D perovskites, mainly attributed to their poor charge transport. Herein, a simple yet universal method for controlling the quality of RPP films by a synergistic effect of two additives in the precursor solution is presented. RPP films achieved by this method show (a) high quality with uniform morphology, enhanced crystallinity, and reduced density of sub-bandgap states, (b) vertically oriented perovskite frameworks that facilitate efficient charge transport, and (c) type-II band alignment that favors self-driven charge separation. Consequently, a hysteresis-free RPP solar cell with a power conversion efficiency exceeding 12%, which is much higher than that of the control device (1.5%), is achieved. The findings will spur new developments in the fabrication of high-quality, aligned, and graded RPP films essential for realizing efficient and stable perovskite solar cells. [ABSTRACT FROM AUTHOR]

Abstract: Recently, Ruddlesden–Popper perovskites (RPPs) have attracted increasing interests due to their promising stability. However, the efficiency of solar cells based on RPPs is much lower than that based on 3D perovskites, mainly attributed to their poor charge transport. Herein, a simple yet universal method for controlling the quality of RPP films by a synergistic effect of two additives in the precursor solution is presented. RPP films achieved by this method show (a) high quality with uniform morphology, enhanced crystallinity, and reduced density of sub‐bandgap states, (b) vertically oriented perovskite frameworks that facilitate efficient charge transport, and (c) type‐II band alignment that favors self‐driven charge separation. Consequently, a hysteresis‐free RPP solar cell with a power conversion efficiency exceeding 12%, which is much higher than that of the control device (1.5%), is achieved. The findings will spur new developments in the fabrication of high‐quality, aligned, and graded RPP films essential for realizing efficient and stable perovskite solar cells. [ABSTRACT FROM AUTHOR]

Abstract: In this article, a voltage doubler circuit designed using 28 nm FD‐SOI technology has been studied for electromagnetic energy harvesting. NLVT transistor type is chosen and used as a diode for the realization of a Dickson voltage doubler circuit. Moreover, the impact of back gate polarization on circuit performance has been analyzed. The optimization of the circuit along with the measurement results has been presented (1.19 V for 1 stage at −26.3 dBm @ 2.45 GHz). [ABSTRACT FROM AUTHOR]

While large carnivores are recovering in Europe, assessing their distributions can help to predict and mitigate conflicts with human activities. Because they are highly mobile, elusive and live at very low density, modeling their distributions presents several challenges due to 1) their imperfect detectability, 2) their dynamic ranges over time and 3) their monitoring at large scales consisting mainly of opportunistic data without a formal measure of the sampling effort. Here, we focused on wolves Canis lupus that have been recolonizing France since the early 1990s. We evaluated the sampling effort a posteriori as the number of observers present per year in a cell based on their location and professional activities. We then assessed wolf range dynamics from 1994 to 2016, while accounting for species imperfect detection and time‐ and space‐varying sampling effort using dynamic site‐occupancy models. Ignoring the effect of sampling effort on species detectability led to underestimating the number of occupied sites by more than 50% on average. Colonization appeared to be negatively influenced by the proportion of a site with an altitude higher than 2500 m and positively influenced by the number of observed occupied sites at short and long‐distances, forest cover, farmland cover and mean altitude. The expansion rate, defined as the number of occupied sites in a given year divided by the number of occupied sites in the previous year, decreased over the first years of the study, then remained stable from 2000 to 2016. Our work shows that opportunistic data can be analyzed with species distribution models that control for imperfect detection, pending a quantification of sampling effort. Our approach has the potential for being used by decision‐makers to target sites where large carnivores are likely to occur and mitigate conflicts. [ABSTRACT FROM AUTHOR]

The article titled "Beyond the Realms of Death" explores the concept of creativity and the role of the Harlequin figure in the author's work. The author discusses their interest in artists such as Gian Lorenzo Bernini, Marcel Duchamp, Leonor Fini, Salvador Dalí, and George Melly, and how these influences have shaped their own artistic endeavors. The article also touches on the challenges of publishing a book related to the author's ongoing project, "Communicating Vessels," and includes a heartfelt eulogy for the late graphic designer Vaughan Oliver. Overall, the article offers a personal reflection on the creative process and the connections between different artistic influences. [Extracted from the article]

At the dawn of the 20th century, the development of the X‐ray and new‐found visions of the interior of bodies inspired artists including Marcel Duchamp. Visual artist and architect Paul O Robinson explores these 'bones and organs' within contemporary contexts, artistically exploiting the shadowy, invisible world of interiority, visible exterior form and the uncanny correspondence between them through transformative spatial and material manifestations. [ABSTRACT FROM AUTHOR]

Contents The effect of cysteamine on in vitro nuclear and cytoplasmic maturation of equine oocytes collected by transvaginal ultrasound guided follicular aspiration was assessed. Oocytes were matured in vitro with (cysteamine group) or without (control group) cysteamine. The nuclear stage after DNA Hoechst staining, penetration rates after two different in vitro fertilization (IVF) techniques (IVF media with ionophore and Hepes buffer with heparin) and the embryo yield following oocyte intra-oviductal transfer were used as a criterion for assessing nuclear and cytoplasmic maturation, respectively. Contrary to the data described in other domestic species, there was no effect of cysteamine on in vitro nuclear maturation, IVF or in vivo embryonic development under our conditions. Ovum pick up yields (52%) and maturation rates (control group: 47% and cysteamine group: 55%) were similar to those previously reported. From 57 oocytes transferred to the oviduct in each group, the number of embryos collected was 10 (17%) in the control group and five in the cysteamine group (9%). Those two percentages were not statistically different (p > 0.05). No effect of IVF technique was seen on the success rate (6%) in each group. [ABSTRACT FROM AUTHOR]

Contents The aim of the present study, was to evaluate whether a single subcutaneous administration of the GnRH analogue buserelin could induce ovulation in the mare during the breeding season. Two studies were carried out under field conditions. In Experiment 1, 90 cycles of trotter mares aged 2–7 years, were assigned to a buserelin group (Bus1) or to a control group (Control), in the presence of a ≥35 mm pre-ovulatory follicle, with uterine oedema and a relaxed cervix. Ten mares were assigned to the two groups for 32 cycles in Bus1 and 52 cycles in Control, two mares received only Bus1 for three cycles, and one mare was assigned to Control for three cycles. Mares treated with buserelin received 6 ml of SUPREFACT® s.c. (1.05 mg/ml buserelin acetate), and no treatment was given in Control. The ovulation rate between 24 and 48 h was higher (p < 0.0001) in Bus1 (31/35) than in Control (15/55). In Experiment 2, the condition of inducing ovulation with 6 ml SUPREFACT® s.c. (Bus2) or 1500 ui human chorionic gonadotropin were identical to the first study. Forty-nine mares of ages 2–21 years, were used for 120 cycles, 56 cycles were assigned to Bus2, and 64 cycles were induced with 1500 IU human chorionic gonadotropin i.v. No significant difference was found in the ovulation rate on day 2 (38/56, 50/64), or in the fertility rate (19/48, 26/57). No negative effect of the treatment was observed with repeated buserelin administration in either study during the breeding season. We can conclude that a single administration of buserelin induces ovulation in the mare, under suitable conditions for veterinary practitioners. [ABSTRACT FROM AUTHOR]

Spontaneous firing of olfactory receptor neurons (ORNs) was recently shown to be required for the survival of ORNs and the maintenance of their appropriate synaptic connections with mitral cells in the olfactory bulb. ORN spontaneous activity has never been described or characterized quantitatively in mammals. To do so we have made extracellular single unit recordings from ORNs of freely breathing (FB) and tracheotomized (TT) rats. We show that the firing behavior of TT neurons was relatively simple: they tended to fire spikes at the same average frequency according to purely random (Poisson) or simple (Gamma or Weibull) statistical laws. A minority of them were bursting with relatively infrequent and short bursts. The activity of FB neurons was less simple: their firing rates were more diverse, some of them showed trends or were driven by breathing. Although more of them were regular, only a minority could be described by simple laws; the majority displayed random bursts with more spikes than the bursts of TT neurons. In both categories bursts and isolated spikes (outside bursts) occurred completely at random. The spontaneous activity of ORNs in rats resembles that of frogs, but is higher, which may be due to a difference in body temperature. These results suggest that, in addition to the intrinsic thermal noise, spontaneous activity is provoked in part by mechanical, thermal, or chemical (odorant molecules) effects of air movements due to respiration, this extrinsic part being naturally larger in FB neurons. It is suggested that spontaneous activity may be modulated by respiration. Because natural sampling of odors is synchronized with breathing, such modulation may prepare and keep olfactory bulb circuits tuned to process odor stimuli. © 2005 Wiley Periodicals, Inc. J Neurobiol, 2005 [ABSTRACT FROM AUTHOR]

Most odours are complex mixtures. However, the capacities of olfactory sensory neurons (OSNs) to process complex odour stimuli have never been explored in air-breathing vertebrates. To face this issue, the present study compares the electrical responses of single OSNs to two odour molecules, delivered singly and mixed together, in rats in vivo. This work is the first aimed at demonstrating that single OSNs simultaneously integrate several chemical signals and which, furthermore, attempts to describe such processes for the whole concentration range over which single OSNs can work. The results stress that complex interactions occur between components in odour mixtures and that OSN responses to such mixtures are not simply predictable from the responses to their components. Three types of interactions are described. They are termed suppression, hypoadditivity and synergy, in accord with psychophysical terminology. This allows us to draw links between peripheral odour reception and central odour coding. Indeed, events occurring in single OSNs may account for the dominating or even the masking effects of odour molecules in complex mixtures, i.e. for the prevailing action of a minor component in the final qualitative perception of a mixture. We conclude that our observations with binary mixtures anticipate the complexity of processes which may rise at the level of a single OSN in physiological conditions. Following this hypothesis, a natural odour would induce a multi-chemical integration at the level of single OSNs which may result in refining their individual odour-coding properties, leading them to play a crucial role in the final performance of the olfactory system. [ABSTRACT FROM AUTHOR]

Mineralogical and geochemical analyses conducted on cores located on the active channel-levee system of the northern Bengal Fan are used to establish changes in the weathering pattern and the sediment transport of the Himalayan system, and evaluate the effect of Indian summer monsoon rainfall during the Holocene. Our data indicate that during the Holocene, sediments from the northern Bengal Fan originate mainly from the G-B river system without any significant changes in the relative contribution of these rivers. From 9.8 to around 6 ka, relatively low smectite/(illite+chlorite) ratios and relatively high K/Si* ratios indicate high physical denudation rates of the Himalayan highlands together with a rapid transfer of the detrital material to the Bengal Fan. The period between 9.2 and 7 ka is associated to lower values of K/Si* and corresponds to the maximum of Indian monsoon rainfall which indicates a more important chemical weathering material that rapidly transits by the G-B river system without a long storage in the Indo-Gangetic plain. From 6.0 ka to present day, higher smectite/(illite+chlorite) ratio and lower K/Si* ratio document a gradual increase of sediments originated from the Indo-Gangetic plain, characterized by higher degree of chemical weathering. During the last 2.5 ka, the drastic increase in the smectite/(illite+chlorite) ratio could be associated to enhanced alteration of the plain soils due to anthropogenic activity. The comparison of mineralogical and geochemical data with previous reconstructions of the Indian monsoon dynamic indicates a rapid response of erosion and sediment transfer of the G-B river system to changes of monsoon rainfall intensity. [ABSTRACT FROM AUTHOR]

Summary The objects of this study were to monitor the development of the cumulus complex and nuclear maturation in oocytes recovered from preovulatory follicles following treatment to induce ovulation and to investigate the in vitro maturation competence of oocytes recovered from smaller nonpreovulatory follicles of varying size. All follicles ≤5 mm in pony mares were individually punctured at 0, 6, 12, 24 and 35 h after an injection of LH to induce ovulation. The recovery rates of oocytes were 64% from 55 preovulatory follicles, 22% from 32 subordinate follicles and 52% from 227 small follicles. Cumulus expansion of the preovulatory oocytes occurred at 12 h post LH treatment while the metaphase I and II components of nuclear maturation were not completed until 24 and 35 h post LH respectively. For nonpreovulatory follicles, the frequency of atresia and oocyte competence for in vitro nuclear maturation both increased with increasing follicular size. [ABSTRACT FROM AUTHOR]

Single-crystalline vanadium dioxide (VO2) nanostructures are of great interest because of their single-domain metal-to-insulator transition. In this paper, single-crystalline W-doped VO2 nanobeams are synthesized for optical and electrical applications. As a result of differences in the polarization of the beams along their transverse and longitudinal axes, dual-surface plasmon resonance peaks at 1344 and 619 nm are generated, resulting in an increase in the solar modulating abilities of the VO2 nanobeams. The conductivity of the single-crystalline W-doped VO2 nanobeams changes by three to four orders of magnitude at the transition temperature, which is of great importance for electrical applications. [ABSTRACT FROM AUTHOR]

Contents The aim of this study was to compare the effects of treatment with repeated injections of sulpiride (a dopamine D[sub 2] antagonist) on prolactin secretion and induced lactation in ovariectomized and intact adult mares and to verify if this induction was possible at the beginning and at the end of the birth season. Two experiments were carried out in September [experiment (expt) 1], and in March (expt 2), in France (48°N). In expt 1, three groups of five mares were tested: intact-control, intact-treated and ovariectomized-treated mares. In expt 2, mares previously subjected to artificial photoperiod were assigned in two groups: four intact-control and five intact-treated mares. The cyclicity of intact mares was previously synchronized with PGF[sub 2α ] injections, then all the mares were in the follicular phase at the beginning of treatment. Sulpiride was intramuscularly injected (0.5 mg/kg of BW), twice a day. Mares were milked at 7:30, 11:45, 16:00 and 20:15 hours. Blood samples were collected every day during the treatment for progesterone, total oestrogen and prolactin assays. In the two experiments, only treated intact mares produced milk, with a large inter-animal variability. Prolactin increase after sulpiride treatment was not so great in the ovariectomized-treated mares as in the intact-treated mares. The total correlations between prolactin, progesterone, oestrogen plasma concentrations and daily milk production were significant (0.57, 0.25, 0.17 respectively). This induction of lactation can be performed during the entire birth season in intact mares, but not in ovariectomized mares, indicating that steroids are necessary for this induction in mares treated by dopamine D2 antagonist. [ABSTRACT FROM AUTHOR]

The phospholipid fatty acid (FA) composition and functional properties of skeletal muscle and liver mitochondria were examined in cold-acclimated (CA, 4°C) ducklings. Phospholipid FA of isolated muscle mitochondria from CA birds were longer and more unsaturated than those from thermoneutral (TN, 25°C) reared ducklings. The rise in long-chain and polyunsaturated FA (PUFA, mainly 20∶4n-6) was associated with a higher State 4 respiration rate and a lower respiratory control ratio (RCR). Hepatic mitochondria, by contrast, were much less affected by cold acclimation. The cold-induced changes in phospholipid FA profile and functional properties of muscle mitochondria were reproduced by giving TN ducklings a diet enriched in grapeseed oil (GO, rich in n-6 FA), suggesting a causal relationship between the membrane structure and mitochondrial functional parameters. However, hepatic mitochondria from ducklings fed the GO diet also showed an enrichment in long-chain PUFA but opposite changes in their biochemical characteristics (lower State 4, higher RCR). It is suggested that the differential modulation of mitochondrial functional properties by membrane lipid composition between skeletal muscle and liver may depend on muscle-specific factors possibly interacting with long-chain PUFA and affecting the proton leakiness of mitochondrial membranes. [ABSTRACT FROM AUTHOR]

An air‐filled substrate integrated waveguide (AFSIW) slot array antenna based on multilayer PCB process is proposed. For comparison and demonstration purposes, 1 × 4 slot array antennas based on both AFSIW and conventional dielectric‐filled SIW (DFSIW) operating at 30.5 GHz are designed, fabricated and measured. The exampled AFSIW 1 × 4 slot array antenna achieves 44 and 18% narrower measured H‐plane and E‐plane half‐power beamwidth, respectively, and simulated radiation efficiency improved by 1.6%, resulting in an overall measured gain improvement of 3.5 dB compared with its DFSIW counterpart. This antenna is of high interest for the design of efficient arrays based on high‐performance AFSIW feeding network. [ABSTRACT FROM AUTHOR]

A substantial reduction of substrate integrated waveguide (SIW) insertion loss can be achieved through the use of air as dielectric instead of usual dielectric material. However, air‐filled SIW (AFSIW) circuits exhibit larger footprint compared with their dielectric‐filled counterparts. A compact multilayer AFSIW bandpass filter is proposed to realise both high‐performance and small footprint. For demonstration purpose, a Ka‐band multilayer fourth‐order AFSIW bandpass filter has been designed and fabricated. Measured and simulated results are in good agreement. Retro‐simulations, taking into account fabrication tolerances, are also presented. Finally, a performance comparison with other multilayer technologies is presented. [ABSTRACT FROM AUTHOR]

Peripheral B-lymphocytes undergo a series of changes during the first few years of life. Encounters with foreign antigens lead to maturation and differentiation. Several primary antibody deficiencies (PADs) affecting B-cell development are associated with abnormalities in the composition and/or differentiation of B-cell compartments. The most recent international classifications of primary immunodeficiencies (PIDs) and common variable immunodeficiencies (CVID) have highlighted the importance of B-cell immunophenotyping and age-specific reference intervals for diagnostic purposes. We established national reference values for memory B-cell subpopulations, on the basis of CD27 and surface IgD expression in the peripheral blood of 242 healthy children. We report here the absolute counts and percentages of naive, switched and non-switched memory B-cells for seven age groups, from neonates to adults. We found that the naive B-cells percentage declined between the ages of 6 months and 8 years, after which it remained stable at about 70-80%. Memory B-cells are already present at birth and their numbers increase throughout childhood, stabilizing between the ages of 12 and 18 years. The definition of reference intervals for pediatric B-cell levels should facilitate the screening and diagnosis of various B-cell immunodeficiencies. This multicenter study, providing national reference values, should thus facilitate immunological diagnosis in children. [ABSTRACT FROM AUTHOR]

ABSTRACT Thyroid hormones (TH) are major contributor to oxidative stress in mammals because they (1) stimulate reactive oxygen species generation (ROS), (2) impair antioxidant defenses, and (3) increase the susceptibility to free radicals of most tissues. Unlike mammals, THs seem to diminish mitochondrial ROS while they have limited effect on the antioxidant machinery in birds. However, how THs modify the susceptibility to ROS has never been explored in an avian model, and very little is known about their effect on oxidative balance in birds. Therefore, the objective of our study was to examine the effect of chronic pharmacological hypo- and hyperthyroidism on (i) the susceptibility of mitochondrial membranes to ROS; and (ii) the level of oxidative stress assessed by measuring oxidative damage to lipids, nucleic acids and proteins in the gastrocnemius muscle of ducklings. We show that hypothyroidism had no effect on the susceptibility of mitochondrial membranes to free radicals. Hypothyroid ducklings had lower oxidized lipids (−31%) and DNA (−25%) but a similar level of protein carbonylation relative to controls. Conversely, mitochondrial membranes of hyperthyroid ducklings exhibited higher unsaturation (+12%) and peroxidation (+31%) indexes than in controls indicating a greater susceptibility to free radicals. However, hyperthyroid ducklings exhibited more oxidative damages on proteins (+67%) only, whereas lipid damages remained unchanged, and there was a slight reduction (−15%) in damages to DNA compared to euthyroid controls. Our results indicate that birds and mammals present fundamental differences in their oxidative stress response to thyroid status. J. Exp. Zool. 321A: 415-421, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Key points Olfactory function is largely under metabolic influence., Insulin, one of the major players between food intake and energy balance, is known to act at both central and peripheral levels., The present study assesses the action of insulin in olfactory bulb slices by using patch-clamp recordings in young rats., The results show that insulin can alter both spontaneous and olfactory nerve-induced firing activities in most of the main ouput neurons, this action being differentially exerted in two opposite directions., A mathematical model demonstrates that insulin, by acting in this way, could impact odour detection and discrimination mechanisms. Such an impact could be hypothesized as being exerted according to pertinent ecological characteristics, such as the alimentary/ethological valence of odour., Abstract Odour perception depends closely on nutritional status, in animals as in humans. Insulin, the principal anorectic hormone, appears to be one of the major candidates for ensuring the link between olfactory abilities and nutritional status, by modifying processing in the olfactory bulb (OB), one of its main central targets. The present study investigates whether and how insulin can act in OB, by evaluating its action on the main output neurons activities, mitral cells (MCs), in acute rat OB slices. Insulin was found to act at two OB network levels: (1) on MCs, by increasing their excitability, probably by inhibiting two voltage-gated potassium (K+) channels; (2) on interneurons by modifying the GABAergic and on glutamatergic synaptic activity impinging on MCs, mainly reducing them. Insulin also altered the olfactory nerve (ON)-evoked excitatory postsynaptic currents in 60% of MCs. Insulin decreased or increased the ON-evoked responses in equal proportion and the direction of its effect depended on the initial neuron ON-evoked firing rate. Indeed, insulin tended to decrease the high and to increase the low ON-evoked firing rates, thereby reducing inter-MC response firing variability. Therefore, the effects of insulin on the evoked firing rates were not carried out indiscriminately in the MC population. By constructing a mathematical model, the impact of insulin complex effects on OB was assessed at the population activity level. The model shows that the reduction of variability across cells could affect MC detection and discrimination abilities, mainly by decreasing and, less frequently, increasing them, depending on odour quality. Thus, as previously proposed, this differential action of insulin on MCs across odours would allow this hormone to put the olfactory function under feeding signal control, given the discerning valence of an odour as a function of nutritional status. [ABSTRACT FROM AUTHOR]

Summary In the mare, success rates for the in vitro maturation of oocytes are low. Accordingly, we attempted to determine if immature oocytes could be matured in vivo by injecting them into a preovulatory follicle. Groups of 3-9 oocytes collected from donor mares were transferred under ultrasound control into the preovulatory follicle of a recipient mare that was treated with crude equine pituitary gonadotrophin (CEG) to induce ovulation. Just before ovulation (34 h post treatment) the preovulatory follicle of the recipient mare was punctured to collect both the transferred and the indigenous oocytes to analyse the stages of nuclear maturation. The transfer technique did not impair significantly the final maturation of the recipient preovulatory follicle. The indigenous oocytes within the recipient follicles were recognisable by their larger expanded cumulus of yellow colouration due to high hyaluronic acid content; 7/12 of these oocytes were mature (metaphase II). Around half (42/86; 49%) of the oocytes transferred to preovulatory follicles were recovered subsequently. Most of them showed cumulus expansion (41/42, 6 of which were rich in hyaluronic acid), 13 (32%) were mature, 15 (36%) were immature and 13 (32%) were degenerate. When the indigenous oocyte of the recipient mare was mature, 38% of the transferred oocytes were mature, this rate being no different from the in vitro maturation rate of 46%. This study showed that in vivo maturation of immature oocytes by transfer into a preovulatory follicle in a recipient mare is possible. The maturation rate is not different from the in vitro maturation rate. The technique allows the generation of mature oocytes that have an expanded cumulus rich in hyaluronic acid, similar to the situation in preovulatory oocytes. This result has not been obtained in vitro previously. [ABSTRACT FROM AUTHOR]

Summary Samples of blood and follicular fluid were recovered from 27 Welsh Pony mares at 4 distinct stages of follicular development. Eighteen biochemical parameters were measured in each sample, including sodium, potassium, chloride, glucose, urea, creatinine, calcium, inorganic phosphate, total bilirubin, total protein, albumin, magnesium, triglyceride, total cholesterol, nonesterified fatty acids, alkaline phosphatase, γ-glutamyltransferase and aspartate aminotransferase. The concentrations of progesterone, 17β oestradiol and testosterone, pH and osmolarity, were also measured in all the follicular fluid samples. The concentrations of all proteins measured were lower in follicular fluid than serum whereas the reverse was true in the case of the lipids. Analysis of variance indicated that serum and follicular fluid concentrations of most of the parameters measured varied in parallel. [ABSTRACT FROM AUTHOR]