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Amino acid substitutions and deletions in the Spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants can reduce the effectiveness of monoclonal antibodies (mAbs). In contrast, heterologous polyclonal antibodies raised against S protein, through the recognition of multiple target epitopes, have the potential to maintain neutralization capacities. XAV-19 is a swine glyco-humanized polyclonal neutralizing antibody raised against the receptor binding domain (RBD) of the Wuhan-Hu-1 Spike protein of SARS-CoV-2. XAV-19 target epitopes were found distributed all over the RBD and particularly cover the receptor binding motives (RBMs), in direct contact sites with the angiotensin converting enzyme-2 (ACE-2). Therefore, in Spike/ACE-2 interaction assays, XAV-19 showed potent neutralization capacities of the original Wuhan Spike and of the United Kingdom (Alpha/B.1.1.7) and South African (Beta/B.1.351) variants. These results were confirmed by cytopathogenic assays using Vero E6 and live virus variants including the Brazil (Gamma/P.1) and the Indian (Delta/B.1.617.2) variants. In a selective pressure study on Vero E6 cells conducted over 1 month, no mutation was associated with the addition of increasing doses of XAV-19. The potential to reduce viral load in lungs was confirmed in a human ACE-2 transduced mouse model. XAV-19 is currently evaluated in patients hospitalized for COVID-19-induced moderate pneumonia in phase 2a-2b (NCT04453384) where safety was already demonstrated and in an ongoing 2/3 trial (NCT04928430) to evaluate the efficacy and safety of XAV-19 in patients with moderate-to-severe COVID-19. Owing to its polyclonal nature and its glyco-humanization, XAV-19 may provide a novel safe and effective therapeutic tool to mitigate the severity of coronavirus disease 2019 (COVID-19) including the different variants of concern identified so far.

Optical neural networks (ONNs) are promising hardware platforms for next-generation neuromorphic computing due to their high parallelism, low latency, and low energy consumption. However, previous integrated photonic tensor cores (PTCs) consume numerous single-operand optical modulators for signal and weight encoding, leading to large area costs and high propagation loss to implement large tensor operations. This work proposes a scalable and efficient optical dot-product engine based on customized multi-operand photonic devices, namely multi-operand optical neuron (MOON). We experimentally demonstrate the utility of a MOON using a multi-operand-Mach–Zehnder-interferometer (MOMZI) in image recognition tasks. Specifically, our MOMZI-based ONN achieves a measured accuracy of 85.89 % in the street view house number (SVHN) recognition dataset with 4-bit voltage control precision. Furthermore, our performance analysis reveals that a 128 × 128 MOMZI-based PTCs outperform their counterparts based on single-operand MZIs by one to two order-of-magnitudes in propagation loss, optical delay, and total device footprint, with comparable matrix expressivity.

Context. Due to the high visual extinction and lack of sensitive mid-infrared (MIR) telescopes, the origin and properties of outflows and jets from embedded Class 0 protostars are still poorly constrained. Aims. We aim to characterise the physical, kinematic, and dynamical properties of the HH 211 jet and outflow, one of the youngest protostellar flows. Methods. We used the James Webb Space Telescope (JWST) and its Mid-InfraRed Instrument (MIRI) in the 5–28 µm range to study the embedded HH 211 flow. We mapped a 0′.95 × 0′.22 region, covering the full extent of the blueshifted lobe, the central protostellar region, and a small portion of the redshifted lobe. We extracted spectra along the jet and outflow and constructed line and excitation maps of both atomic and molecular lines. Additional JWST NIRCam H2 narrow-band images (at 2.122 and 3.235 µm) provide a visualextinction map of the whole flow, and are used to deredden our data. Results. The jet-driving source is not detected even at the longest MIR wavelengths. The overall morphology of the flow consists of a highly collimated jet, which is mostly molecular (H2, HD) with an inner atomic ([Fe I], [Fe II], [S I], [Ni II]) structure. The jet shocks the ambient medium, producing several large bow shocks (BSs) that are rich in forbidden atomic ([Fe II], [S I], [Ni II], [Cl I], [Cl II], [Ar II], [Co II], [Ne II], [S III]) and molecular lines (H2, HD, CO, OH, H2O, CO2, HCO+), and is driving an H2 molecular outflow that is mostly traced by low- J, v = 0 transitions. Moreover, H2 0-0 S(1) uncollimated emission is also detected down to 2″-3″ (~650–1000 au) from the source, tracing a cold (T=200–400 K), less dense, and poorly collimated molecular wind. Two H2 components (warm, T =300–1000 K, and hot, T =1000–3500 K) are detected along the jet and outflow. The atomic jet ([Fe II] at 26 µm) is detected down to ~130 au from the source, whereas the lack of H2 emission (at 17 µm) close to the source is likely due to the large visual extinction (AV > 80 mag). Dust-continuum emission is detected at the terminal BSs and in the blue- and redshifted jet, and is likely attributable to dust lifted from the disc. Conclusions. The jet shows an onion-like structure, with layers of different size, velocity, temperature, and chemical composition. Moreover, moving from the inner jet to the outer BSs, different physical, kinematic, and excitation conditions for both molecular and atomic gas are observed. The mass-flux rate and momentum of the jet, as well as the momentum flux of the warm H2 component, are up to one order of magnitude higher than those inferred from the atomic jet component. Our findings indicate that the warm H2 red component is the main driver of the outflow, that is to say it is the most significant dynamical component of the jet, in contrast to jets from more evolved YSOs, where the atomic component is dominant. [ABSTRACT FROM AUTHOR]

Context. Characterising stellar jet asymmetries is key to setting robust constraints on jet launching models and improving our understanding of the underlying mechanisms behind jet launching. Aims. We aim to characterise the asymmetric properties of the bipolar jet coming from the Classical T Tauri Star Th 28. Methods. We combined data from integral field spectroscopy with VLT/MUSE and high-resolution spectra from VLT/X-shooter to map the optical emission line ratios in both jet lobes. We carried out a diagnostic analysis of these ratios to compare the density, electron temperature, and ionisation fraction within both lobes. The mass accretion rate was derived from the emission lines at the source and compared with the mass outflow rate derived for both lobes, using the estimated densities and measured [O I]λ6300 and [S II]λ6731 luminosities. Results. The blue-shifted jet exhibits a significantly higher electron temperature and moderately higher ionisation fraction than the red-shifted jet. In contrast to previous studies, we also estimated higher densities, denoted as nH , in the blue-shifted jet by a factor of ~2. These asymmetries are traced to within 1″ (160 au) of the source in the line ratio maps. We find Ṁacc = 2.4 × 10−7M⊙ yr−1, with an estimated obscuration factor of ~54 due to grey scattering around the star. Estimated values of Ṁout range between 0.66 and 13.7 × 10−9M⊙ yr−1 in the blue-shifted jet and 5–9 × 10−9M⊙ yr−1 in the red-shifted jet. Conclusions. The emission line maps and diagnostic results suggest that the jet asymmetries originate close to the source and are likely to be intrinsic to the jet. Furthermore, the combined dataset offers access to a broad array of accretion tracers. In turn, this enables a more accurate estimation of the mass accretion rate, revealing a value of Ṁacc that is higher by a factor >350 than would otherwise be determined. [ABSTRACT FROM AUTHOR]

The global trends of urbanization and industrialization have given rise to critical environmental and air pollution issues that often receive insufficient attention. Among the myriad pollution sources, volatile organic compounds (VOCs) stand out as a primary cluster, posing a significant threat to human society. Addressing VOCs emissions requires an effective mitigation action plan, placing technological development, especially in detection, at the forefront. Photonic sensing technologies rooted in the infrared (IR) light and matter interaction mechanism offer nondestructive, fast-response, sensitive, and selective chemical measurements, making them a promising solution for VOC detection. Recent strides in nanofabrication processes have facilitated the development of miniaturized photonic devices and thus sparked growing interest in the creation of low-cost, highly selective, sensitive, and fast-response IR optical sensors for VOC detection. This review work thus serves a timely need to provide the community a comprehensive understanding of the state of the art in this field and illuminate the path forward in addressing the pressing issue of VOC pollution. [ABSTRACT FROM AUTHOR]

The Manoomin ''wild rice'' Science Camp program, a partnership between the University of Minnesota, the Fond du Lac Tribal and Community College, and the Fond du Lac Band of Lake Superior Chippewa is an example of how a community-based participatory research project can become the catalyst for STEM learning for an entire community, providing effective learning opportunities for grades 5-12 and undergraduate students, elementary and secondary school teachers, and scientists from the reservation, tribal college, and university. Focusing the research on a resource (wild rice) that has important economic, cultural and spiritual meaning for a community, we promote place-based education and support the development of strong science/teacher/community partnerships. Key components of this approach are the Circle of Learning, a conceptual framework that emphasizes trust- and relationship-building between researchers, teachers, students, and American Indian community members, and the Seven Elements of STEM Learning, a pedagogical framework derived from an extensive review of the literature on American Indian education that focuses on a holistic approach to learning that emphasizes the whole student.

Among avian species, particularly those with altricial young, life‐history strategies are characterized by a 'slow' pace‐of‐life at lower latitudes, where relatively low annual investments in reproduction are traded‐off for increased survival. Evidence for this pattern in precocial species, however, is equivocal, and questions about ecological drivers of latitudinal variation in reproduction remain. To better understand spatial variation in pace‐of‐life and related reproductive traits across bird species and to test a hypothesis that might explain observed spatial patterns, we analysed breeding data from closely related Canada Geese Branta canadensis and Cackling Geese Branta hutchinsii, hereafter Canada‐type geese, comprising eight sub‐species from 16 sites across a broad gradient of latitude (32°N to 69°N) and season length. Unlike the pattern reported for many altricial species, Canada‐type geese did not show reduced annual fecundity at lower latitudes, and instead this reduced reproductive investment was at higher latitudes. For three of five reproductive traits, the relative influence of growing season length (GSL; an index of the time available to breed) was greater than that of latitude. A shorter GSL resulted in later nest initiations, shorter pre‐laying intervals and higher seasonal rates of clutch size decline. Our results suggest that these and other species of geese are able to circumvent nutritional and temporal constraints imposed by shorter GSL by storing and using nutrient reserves for egg laying and incubation. Relative flexibility in reproductive traits may permit Canada‐type geese to accommodate predicted increases in climatic variability, compared to species with more rigid reproductive strategies. [ABSTRACT FROM AUTHOR]

Abstract Background In a warmer and more globally connected Arctic, vector-borne pathogens of zoonotic importance may be increasing in prevalence in native wildlife. Recently, Bartonella henselae, the causative agent of cat scratch fever, was detected in blood collected from arctic foxes (Vulpes lagopus) that were captured and released in the large goose colony at Karrak Lake, Nunavut, Canada. This bacterium is generally associated with cats and cat fleas, which are absent from Arctic ecosystems. Arctic foxes in this region feed extensively on migratory geese, their eggs, and their goslings. Thus, we hypothesized that a nest flea, Ceratophyllus vagabundus vagabundus (Boheman, 1865), may serve as a vector for transmission of Bartonella spp. Methods We determined the prevalence of Bartonella spp. in (i) nest fleas collected from 5 arctic fox dens and (ii) 37 surrounding goose nests, (iii) fleas collected from 20 geese harvested during arrival at the nesting grounds and (iv) blood clots from 57 adult live-captured arctic foxes. A subsample of fleas were identified morphologically as C. v. vagabundus. Remaining fleas were pooled for each nest, den, or host. DNA was extracted from flea pools and blood clots and analyzed with conventional and real-time polymerase chain reactions targeting the 16S-23S rRNA intergenic transcribed spacer region. Results Bartonella henselae was identified in 43% of pooled flea samples from nests and 40% of pooled flea samples from fox dens. Bartonella vinsonii berkhoffii was identified in 30% of pooled flea samples collected from 20 geese. Both B. vinsonii berkhoffii (n = 2) and B. rochalimae (n = 1) were identified in the blood of foxes. Conclusions We confirm that B. henselae, B. vinsonii berkhoffii and B. rochalimae circulate in the Karrak Lake ecosystem and that nest fleas contain B. vinsonii and B. henselae DNA, suggesting that this flea may serve as a potential vector for transmission among Arctic wildlife.

Abstract An effective-area photovoltaic efficiency of 1.27% in power conversion, excluding the grid metal contact area and under 1 sun, AM 1.5G conditions, has been obtained for the p-GaN/i-InGaN/n-GaN diode arrays epitaxially grown on (111)-Si. The short-circuit current density is 14.96 mA/cm2 and the open-circuit voltage is 0.28 V. Enhanced light trapping acquired via multiple reflections within the strain and defect free III-nitride nanorod array structures and the short-wavelength responses boosted by the wide bandgap III-nitride constituents are believed to contribute to the observed enhancements in device performance.

Stars form by accreting material from their surrounding disks. There is a consensus that matter flowing through the disk is channelled onto the stellar surface by the stellar magnetic field. This is thought to be strong enough to truncate the disk close to the corotation radius, at which the disk rotates at the same rate as the star. Spectro-interferometric studies in young stellar objects show that hydrogen emission (a well known tracer of accretion activity) mostly comes from a region a few milliarcseconds across, usually located within the dust sublimation radius.sup.1-3. The origin of the hydrogen emission could be the stellar magnetosphere, a rotating wind or a disk. In the case of intermediate-mass Herbig AeBe stars, the fact that Brackett [gamma] (Br[gamma]) emission is spatially resolved rules out the possibility that most of the emission comes from the magnetosphere.sup.4-6 because the weak magnetic fields (some tenths of a gauss) detected in these sources.sup.7,8 result in very compact magnetospheres. In the case of T Tauri sources, their larger magnetospheres should make them easier to resolve. The small angular size of the magnetosphere (a few tenths of a milliarcsecond), however, along with the presence of winds.sup.9,10 make the interpretation of the observations challenging. Here we report optical long-baseline interferometric observations that spatially resolve the inner disk of the T Tauri star TW Hydrae. We find that the near-infrared hydrogen emission comes from a region approximately 3.5 stellar radii across. This region is within the continuum dusty disk emitting region (7 stellar radii across) and also within the corotation radius, which is twice as big. This indicates that the hydrogen emission originates in the accretion columns (funnel flows of matter accreting onto the star), as expected in magnetospheric accretion models, rather than in a wind emitted at much larger distance (more than one astronomical unit). The size of the inner disk of the T Tauri star TW Hydrae is determined using optical long-baseline interferometric observations, indicating that hydrogen emission comes from a region approximately 3.5 stellar radii across., Author(s): R. Garcia Lopez [sup.1] [sup.1] [sup.2] [sup.3] , A. Natta [sup.2] , A. Caratti o Garatti [sup.1] [sup.2] [sup.3] , T. P. Ray [sup.2] , R. Fedriani [sup.2] [sup.4] [...]

This document is a correction notice for an article titled "JOYS: Disentangling the warm and cold material in the high-mass IRAS 23385+6053 cluster." The article focuses on topics such as star formation, individual objects in the ISM (Interstellar Medium), stars with jets, and massive stars. The full text of the article is not available in HTML format. The authors of the article are listed as C. Gieser, H. Beuther, E. F. van Dishoeck, L. Francis, M. L. van Gelder, L. Tychoniec, P. J. Kavanagh, G. Perotti, A. Caratti o Garatti, T. P. Ray, P. Klaassen, K. Justtanont, H. Linnartz, W. R. M. Rocha, K. Slavicinska, L. Colina, M. Güdel, Th. Henning, P.-O. Lagage, G. Östlin, B. Vandenbussche, C. Waelkens, and G. Wright. [Extracted from the article]

Context. Two protoplanets have recently been discovered within the PDS 70 protoplanetary disk. JWST/NIRCam offers a unique opportunity to characterize them and their birth environment at wavelengths that are difficult to access from the ground. Aims. We image the circumstellar environment of PDS 70 at 1.87 μm and 4.83 μm, assess the presence of Pa-α emission due to accretion onto the protoplanets, and probe any IR excess indicative of heated circumplanetary material. Methods. We obtained noncoronagraphic JWST/NIRCam images of PDS 70 within the MIRI mid-INfrared Disk Survey (MINDS) program. We leveraged the Vortex Image Processing (VIP) package for data reduction, and we developed dedicated routines for optimal stellar point spread function subtraction, unbiased imaging of the disk, and protoplanet flux measurement in this type of dataset. A radiative transfer model of the disk was used to separate the contributions from the disk and the protoplanets. Results. We redetect both protoplanets and identify extended emission after subtracting a disk model, including a large-scale spiral-like feature. We interpret its signal in the direct vicinity of planet c as tracing the accretion stream that feeds its circumplanetary disk, while the outer part of the feature may rather reflect asymmetric illumination of the outer disk. We also report a bright signal that is consistent with a previously proposed protoplanet candidate enshrouded in dust near the 1:2:4 mean-motion resonance with planets b and c. The 1.87 μm flux of planet b is consistent with atmospheric model predictions, but the flux of planet c is not. We discuss potential origins for this discrepancy, including significant Pa-α line emission. The 4.83 μm fluxes of planets b and c suggest enshrouding dust or heated CO emission from their circumplanetary environment. Conclusions. The use of image-processing methods that are optimized for extended disk signals on high-sensitivity and high-stability from JWST can uniquely identify signatures of planet–disk interactions and enable accurate photometry of protoplanets at wavelengths that are difficult to probe from the ground. Our results indicate that more protoplanets can be identified and characterized in other JWST datasets. [ABSTRACT FROM AUTHOR]

Context. Space-based mid-infrared (IR) spectroscopy is a powerful tool for the characterization of important star formation tracers of warm gas which are unobservable from the ground. The previous mid-IR spectra of bright high-mass protostars with the Infrared Space Observatory (ISO) in the hot-core phase typically show strong absorption features from molecules such as CO2, C2H2, and HCN. However, little is known about their fainter counterparts at earlier stages. Aims. We aim to characterize the gas-phase molecular features in James Webb Space Telescope Mid-Infrared Instrument Medium Resolution Spectrometer (MIRI/MRS) spectra of the young and clustered high-mass star-forming region IRAS 23385+6053. Methods. Spectra were extracted from several locations in the MIRI/MRS field of view, targeting two mid-IR sources tracing embedded massive protostars as well as three H2 bright outflow knots at distances of >8000 au from the multiple. Molecular features in the spectra were fit with local thermodynamic equilibrium (LTE) slab models, with their caveats discussed in detail. Results. Rich molecular spectra with emission from CO, H2, HD, H2O, C2H2, HCN, CO2, and OH are detected towards the two mid-IR sources. However, only CO and OH are seen towards the brightest H2 knot positions, suggesting that the majority of the observed species are associated with disks or hot core regions rather than outflows or shocks. The LTE model fits to 12CO2, C2H2, HCN emission suggest warm 120–200 K emission arising from a disk surface around one or both protostars. The abundances of CO2 and C2H2 of ~10−7 are consistent with previous observations of high-mass protostars. Weak ~500 K H2O emission at ~6–7 µm is detected towards one mid-IR source, whereas 250–1050 K H2O absorption is found in the other. The H2O absorption may occur in the disk atmosphere due to strong accretion-heating of the midplane, or in a disk wind viewed at an ideal angle for absorption. CO emission may originate in the hot inner disk or outflow shocks, but NIRSpec data covering the 4.6 µm band head are required to determine the physical conditions of the CO gas, as the high temperatures seen in the MIRI data may be due to optical depth. OH emission is detected towards both mid-IR source positions and one of the shocks, and is likely excited by water photodissociation or chemical formation pumping in a highly non-LTE manner. Conclusions. The observed molecular spectra are consistent with disks having already formed around two protostars in the young IRAS 23385+6054 system. Molecular features mostly appear in emission from a variety of species, in contrast to the more evolved hot core phase protostars which typically show only absorption; however, further observations of young high-mass protostars are needed to disentangle geometry and viewing angle effects from evolution. [ABSTRACT FROM AUTHOR]

Photonic computing shows promise for transformative advancements in machine learning (ML) acceleration, offering ultrafast speed, massive parallelism, and high energy efficiency. However, current photonic tensor core (PTC) designs based on standard optical components hinder scalability and compute density due to their large spatial footprint. To address this, we propose an ultracompact PTC using customized programmable multi-operand multimode interference (MOMMI) devices, named M3ICRO. The programmable MOMMI leverages the intrinsic light propagation principle, providing a single-device programmable matrix unit beyond the conventional computing paradigm of one multiply-accumulate operation per device. To overcome the optimization difficulty of customized devices that often requires time-consuming simulation, we apply ML for optics to predict the device behavior and enable differentiable optimization flow. We thoroughly investigate the reconfigurability and matrix expressivity of our customized PTC and introduce a novel block unfolding method to fully exploit the computing capabilities of a complex-valued PTC for near-universal real-valued linear transformations. Extensive evaluations demonstrate that M3ICRO achieves a 3.5–8.9× smaller footprint, 1.6–4.4× higher speed, 9.9–38.5× higher compute density, 3.7–12× higher system throughput, and superior noise robustness compared to state-of-the-art coherent PTC designs. It also outperforms electronic digital A100 graphics processing unit by 34.8–403× higher throughput while maintaining close-to-digital task accuracy across various ML benchmarks. [ABSTRACT FROM AUTHOR]