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From March to December 2014, Loon LLC flew 107 super-pressure balloons in the lower stratosphere over the Southern Ocean. Their GPS sampling frequency of 1Hz allowed them to sample motion associated with atmospheric internal gravity waves generated by the Andes mountains, small islands, and non-orographic sources such as fronts. Analyzing the balloons’ data time series using wavelets, we present distributions of the gravity waves’ momentum fluxes, phase speeds, and wavelengths, both in the time-mean and as they vary from month to month. Many climate models parameterize gravity waves using a phase speed-momentum flux relationship, so we focus on the relationship between those quantities.

Ultra-high performance concrete (UHPC) is a relatively modern class of concrete with properties that include very high compressive strengths, increased tensile strengths, very low permeability, and superior durability compared to conventional, normal-strength concrete. As research of this material continues to progress, its applications under both military and civil works categories expand. However, mixture and structural design guidance using UHPC is limited, particularly in the United States. This special report provides an overview of UHPC as initial guidance for the US Army Corps of Engineers (USACE) so that the material may be more easily utilized in civil works infrastructure. The information contained in this report is based on years of experience researching and developing UHPC at the US Army Engineer Research and Development Center (ERDC) and is intended to be a basis for the incorporation of this material class into USACE Engineer Manual (EM) 1110-2-2000, Standard Practice for Concrete for Civil Works Structures, when it is next updated.

Convection-generated gravity waves (CGWs) transport momentum and energy, and this momentum is a dominant driver of global features of Earth’s atmosphere’s general circulation (e.g. the quasi-biennial oscillation, the pole-to-pole mesospheric circulation). As CGWs are not generally resolved by global weather and climate models, their effects on the circulation need to be parameterized. However, quality observations of GWs are spatiotemporally sparse, limiting understanding and preventing constraints on parameterizations. Convection-permitting or -resolving simulations do generate CGWs, but validation is not possible as these simulations cannot reproduce the forcing convection at correct times, locations, and intensities.Here, realistic convective diabatic heating, learned from full-physics convection-permitting Weather Research and Forecasting (WRF) simulations, is predicted from weather radar observations using neural networks and a previously developed look-up table. These heating rates are then used to force an idealized GW-resolving dynamical model. Simulated CGWs forced in this way did closely resemble those observed by the Atmospheric InfraRed Sounder in the upper stratosphere. CGW drag in these validated simulations extends 100s of kilometers away from the convective sources, highlighting errors in current gravity wave drag parameterizations due to the use of the ubiquitous single-column approximation. Such validatable simulations have significant potential to be used to further basic understanding of CGWs, improve their parameterizations physically, and provide more restrictive constraints on tuning \textit{with confidence}.

To assess the risk of aerosol transmission of SARS-CoV-2, measurements of the airborne viral concentrations in proximity to infected individuals, the persistence of the virus in aerosols, and the d...

Convection, both observed and modeled, generates gravity waves (GWs) that significantly impact large-scale circulations in the stratosphere and above. However, models that permit convection and resolve the GWs they generate cannot reproduce the timing, location, and intensity of the actual convective cells that generate the observed convective GWs. This issue prevents comparison of observed and modeled convective GWs and model validation/evaluation. Here, convective latent heating is predicted based on radar observations and provided to an idealized version of WRF, allowing WRF’s dynamics to generate convective updrafts/downdrafts and generated convective GWs both mechanically and diabatically. Two methods are used to predict convective latent heating: the composited lookup table of Bramberger et al. 2020 and neural networks (NNs) using the same, and additional, input variables. Offline performance of the NN-predicted latent heating can be improved over the previous method when more input variables are used. Preliminary comparisons of modeled and observed (via superpressure-balloon and satellite) convective GWs will be presented.

Previous studies have demonstrated that SARS-CoV-2 is stable on surfaces for extended periods under indoor conditions. In the present study, simulated sunlight rapidly inactivated SARS-CoV-2 suspended in either simulated saliva or culture media and dried on stainless steel coupons. Ninety percent of infectious virus was inactivated every 6.8 minutes in simulated saliva and every 14.3 minutes in culture media when exposed to simulated sunlight representative of the summer solstice at 40°N latitude at sea level on a clear day. Significant inactivation also occurred, albeit at a slower rate, under lower simulated sunlight levels. The present study provides the first evidence that sunlight may rapidly inactivate SARS-CoV-2 on surfaces, suggesting that persistence, and subsequently exposure risk, may vary significantly between indoor and outdoor environments. Additionally, these data indicate that natural sunlight may be effective as a disinfectant for contaminated nonporous materials., This study provides the first evidence that sunlight may rapidly inactivate SARS-CoV-2 on surfaces, suggesting that persistence, and subsequently exposure risk, may vary significantly between indoor and outdoor environments.

Due to the shortage of pediatric dermatologists and the abundance of skin disorders presenting in childhood, general pediatricians shoulder the management of many pediatric dermatologic disorders and would benefit from additional dermatology-specific training. To address this educational gap, general pediatricians were enrolled in a pediatric dermatology-specific Project Extension for Community Healthcare Outcomes (ECHO) program and surveyed to assess the efficacy of the program in increasing providers' ability and confidence in managing pediatric dermatologic conditions. Providers unanimously reported increased confidence and abilities in assessment and management of pediatric dermatologic conditions. Pediatric dermatology Project ECHO demonstrated high efficacy in improving general practitioners' comfort and knowledge on dermatology-specific topics and may be used as an education model for enhancing primary care providers' knowledge and management of common disorders.

Background Portal vein resection (PVR) with pancreaticoduodenectomy (PD) is often performed to achieve clear margins for patients with vascular involvement in pancreatic ductal adenocarcinoma (PDAC). However, there is evidence to suggest that patients undergoing PVR often have more advanced cancers, therefore the impact of PVR on survival and recurrence remains unclear. The aim of this study is to assess overall (OS) and recurrence free (RFS) survival in patients who underwent PVR during PD, with particular attention to margin positivity. Methods A retrospective analysis was performed on 638 patients who underwent PD during a 12-year period. Exclusion criteria included PD for non-PDAC tumours, neoadjuvant chemotherapy or intra-operative radiotherapy. 374 patients were included in the study (90 PVR and 284 non-PVR). Patient characteristics and histopathological factors associated with OS and RFS were then evaluated using univariate and multivariate Cox regression analyses. 270 patients (90 PVR and 180 non-PVR), were matched by propensity score based on perineural invasion, pT and pN staging. The Kaplan-Meier method was used to calculate survival and log-rank tests. Results Resection margin positivity was associated with shorter OS and RFS (p Conclusions Positive resection margins are associated with shorter survival times, and the SMV margin is the most significant prognostic indicator for overall survival and recurrence compared to other margins. PVR is a relatively safe procedure, however, it does not achieve the intended survival benefits of complete margin clearance. The impact on survival for margin positivity, particularly the SMV margin, and nodal metastasis should be considered when making decisions with regards to vein resection and adjuvant treatments.

While evidence exists supporting the potential for aerosol transmission of SARS-CoV-2, the infectious dose by inhalation remains unknown. In the present study, the probability of infection following inhalation of SARS-CoV-2 was dose-dependent in a nonhuman primate model of inhalational COVID-19. The median infectious dose, assessed by seroconversion, was 52 TCID50 (95% CI: 23–363 TCID50), and was significantly lower than the median dose for fever (256 TCID50, 95% CI: 102–603 TCID50), resulting in a group of animals that developed an immune response post-exposure but did not develop fever or other clinical signs of infection. In a subset of these animals, virus was detected in nasopharyngeal and/or oropharyngeal swabs, suggesting that infected animals without signs of disease are able to shed virus and may be infectious, which is consistent with reports of asymptomatic spread in human cases of COVID-19. These results suggest that differences in exposure dose may be a factor influencing disease presentation in humans, and reinforce the importance of public health measures that limit exposure dose, such as social distancing, masking, and increased ventilation. The dose-response data provided by this study are important to inform disease transmission and hazard modeling, and, ultimately, mitigation strategies. Additionally, these data will be useful to inform dose selection in future studies examining the efficacy of therapeutics and vaccines against inhalational COVID-19, and as a baseline in healthy, young adult animals for assessment of the importance of other factors, such as age, comorbidities, and viral variant, on the infectious dose and disease presentation., Author summary SARS-CoV-2 infection and subsequent disease presentation are dependent on exposure dose in a nonhuman primate model of inhalational COVID-19.

Motivated by observations of southward ocean heat transport (OHT) in the northern Indian Ocean during summer, the role of the ocean in modulating monsoon circulations is explored by coupling an atmospheric model to a slab ocean with an interactive representation of OHT and an idealized subtropical continent. Southward OHT by the cross-equatorial cells is caused by Ekman flow driven by southwesterly monsoon winds in the summer months, cooling sea surface temperatures (SSTs) south of the continent. This increases the reversed meridional surface gradient of moist static energy, shifting the precipitation maximum over the land and strengthening the monsoonal circulation, in the sense of enhancing the vertical wind shear. However, the atmosphere’s cross-equatorial meridional overturning circulation is also weakened by the presence of southward OHT, as the atmosphere is required to transport less energy across the equator. The sensitivity of these effects to varying the strength of the OHT, fixing the OHT at its annual-mean value, and to removing the land is explored. Comparisons with more realistic models suggest that the idealized model used in this study produces a reasonable representation of the effect of OHT on SSTs equatorward of subtropical continents, and hence can be used to study the role of OHT in shaping monsoon circulations on Earth.

Candida glabrata is an opportunistic pathogen of humans, responsible for up to 30% of disseminated candidiasis. Adherence of C. glabrata to host cells is mediated by adhesin-like proteins (ALPs), about half of which are encoded in the subtelomeres. We performed a de novo assembly of two C. glabrata strains, BG2 and BG3993, using long single-molecule real-time (SMRT) reads, and constructed high-quality telomere-to-telomere assemblies of all 13 chromosomes to assess differences between C. glabrata strains. We documented variation between strains, and in agreement with earlier studies, found high (~0.5%-1%) frequencies of SNVs across the genome, including within subtelomeric regions. We documented changes in ALP gene structure and complement: there are large length differences in ALP genes in different strains, resulting from copy number variation in tandem repeats. We compared strains to characterize chromosome rearrangement events including within the poorly characterized subtelomeric regions. We show that rearrangements within the subtelomere regions all affect ALP-encoding genes, and 14/16 involve just the most terminal ALP gene. We present evidence that these rearrangements are mediated by break-induced replication. This study highlights the constrained nature of subtelomeric changes impacting ALP gene complement and subtelomere structure.

Recent evidence suggests that respiratory aerosols may play a role in the spread of SARS-CoV-2 during the ongoing COVID-19 pandemic. Our laboratory has previously demonstrated that simulated sunlig...

Aerosols represent a potential transmission route of COVID-19. This study examined effect of simulated sunlight, relative humidity, and suspension matrix on stability of SARS-CoV-2 in aerosols. Simulated sunlight and matrix significantly affected decay rate of the virus. Relative humidity alone did not affect the decay rate; however, minor interactions between relative humidity and other factors were observed. Mean decay rates (± SD) in simulated saliva, under simulated sunlight levels representative of late winter/early fall and summer were 0.121 ± 0.017 min−1 (90% loss, 19 minutes) and 0.306 ± 0.097 min−1 (90% loss, 8 minutes), respectively. Mean decay rate without simulated sunlight across all relative humidity levels was 0.008 ± 0.011 min−1 (90% loss, 286 minutes). These results suggest that the potential for aerosol transmission of SARS-CoV-2 may be dependent on environmental conditions, particularly sunlight. These data may be useful to inform mitigation strategies to minimize the potential for aerosol transmission.

The atmospheric Hadley cells, which meet at the Intertropical Convergence Zone (ITCZ), play critical roles in transporting heat, driving ocean circulation and supplying precipitation to the most heavily populated regions of the globe. Paleo-reconstructions can provide concrete evidence of how these major features of the atmospheric circulation can change in response to climate perturbations. While most such reconstructions have focused on ITCZ-related rainfall, here we show that trade wind proxies can document dynamical aspects of meridional ITCZ shifts. Theoretical expectations based on angular momentum constraints and results from freshwater hosing simulations with two different climate models predict that ITCZ shifts due to anomalous cooling of one hemisphere would be accompanied by a strengthening of the Hadley cell and trade winds in the colder hemisphere, with an opposite response in the warmer hemisphere. This expectation of hemispherically asymmetric trade wind changes is confirmed by proxy data of coastal upwelling and windblown dust from the Atlantic basin during Heinrich stadials, showing trade wind strengthening in the Northern Hemisphere and weakening in the Southern Hemisphere subtropics in concert with southward ITCZ shifts. Data from other basins show broadly similar patterns, though improved constraints on past trade wind changes are needed outside the Atlantic Basin. The asymmetric trade wind changes identified here suggest that ITCZ shifts are also marked by intensification of the ocean's wind-driven subtropical cells in the cooler hemisphere and a weakening in the warmer hemisphere, which induces cross-equatorial oceanic heat transport into the colder hemisphere. This response would be expected to prevent extreme meridional ITCZ shifts in response to asymmetric heating or cooling. Understanding trade wind changes and their coupling to cross-equatorial ocean cells is key to better constraining ITCZ shifts and ocean and atmosphere dynamical changes in the past, especially for regions and time periods for which few paleodata exist, and also improves our understanding of what changes may occur in the future.

Multi-layer optical thin films can reflect light to guide it along a hollow tube that they internally line. However, reflecting broadband white light for a range of angles requires many precise thin optical layers, which can be too expensive for large-scale applications such as architectural illumination. Here, we present an alternative configuration that requires only one readily achievable aspect of precision—having a substantially constant cross section, perpendicular to the planned longitudinal propagation direction. This aspect conserves a light ray’s longitudinal directional component, while the ray’s path in the perpendicular direction can be macroscopically chaotic, much like the diffuse reflection characteristic arising from many non-absorbing pigment particles. This macroscopic characteristic is described here as “longitudinally specular” and “transversely diffuse.” This new design overcomes two problems that are found with current prism light guides (PLGs), which are a class of hollow light guides that also have a constant cross section. The PLG has two problems: (1) it requires structured surfaces having near-perfect linear prisms that are much larger than the wavelength of light, wasting optical material and increasing absorption; (2) it only works well with light that has been partially collimated, which limits étendue and requires expensive, inefficient input optics. In this paper, a new, to the best of our knowledge, approach, labeled a “multi-layer prism light guide,” simultaneously addresses both problems. Although the new structure is more complex than a conventional PLG, it may be simpler to manufacture. One potential application is for guiding sunlight into buildings for illumination purposes, without requiring complex sun-tracking solar collection optics.

The Intertropical Convergence Zone (ITCZ) is a global-scale band of tropical precipitation lying, in the annual mean, just north of the equator. Its position can be tied to the atmosphere's energy balance: the Northern Hemisphere is heated more strongly than the Southern Hemisphere, biasing the atmosphere's circulation and ITCZ north of the equator. In the context of this energy balance framework, we examine multidecadal connections between variations in the position of the global ITCZ and indices of extratropical sea surface temperature (SST) variability over the twentieth century. We find that the ITCZ and atmospheric circulation are shifted farther to the north during periods when North Atlantic and North Pacific SSTs are anomalously warm. Additionally, a warmer North Atlantic is correlated with a relatively warm Northern Hemisphere atmosphere. Our results suggest an important role for the ocean circulation in modulating ITCZ migrations on decade-and-longer timescales., United States. National Oceanic and Atmospheric Administration

Varanus rosenbergi females oviposit in nests excavated in termite mounds in summer, and hatching occurs the following spring after a seven-month incubation period. In this study, we characterized developmental features associated with the prolonged incubation of this species at Kangaroo Island in South Australia. Oviposition occurs shortly after limb buds have formed, and the subsequent pattern of organogenesis is similar to that of other lizards. Survival of eggs incubated at constant temperatures ranging from 26–33°C was 89–100%, whereas survival at 24°C and at 35°C was 0 and 14%, respectively. During the incubation period, mean ambient temperature at Kangaroo Island (14–15°C) is too low for successful reproduction, whereas mean temperatures in termite mounds (27–37°C) are substantially warmer and similar to the estimated mean incubation temperature (26–27°C). Therefore, successful reproduction by V. rosenbergi in southern Australia may be contingent on nesting in termitaria. Varanids, in gener...

The position of the intertropical convergence zone (ITCZ) is sensitive to the atmosphere’s hemispheric energy balance, lying in the hemisphere most strongly heated by radiative and turbulent surface energy fluxes. This study examines how the ocean circulation, through its cross-equatorial energy transport and associated surface energy fluxes, affects the ITCZ’s response to an imposed interhemispheric heating contrast in a coupled atmosphere–ocean general circulation model. Shifts of the ITCZ are strongly damped owing to a robust coupling between the atmosphere’s Hadley cells and the ocean’s subtropical cells by the trade winds and their associated surface stresses. An anomalous oceanic wind-driven cross-equatorial cell transports energy across the equator, strongly offsetting the imposed heating contrast. The circulation of this cell can be described by the combination of trade wind anomalies and the meridional gradient of sea surface temperature, which sets the temperature contrast between its upper and lower branches. The ability of the wind-driven ocean circulation to damp ITCZ shifts represents a previously unappreciated constraint on the atmosphere’s energy budget and indicates that the position of the ITCZ may be much less sensitive to interhemispheric heating contrasts than previously thought. Climatic implications of this damping are discussed.

Candida glabratais an opportunistic pathogen in humans, responsible for approximately 20% of disseminated candidiasis. Candida glabrata's ability to adhere to host tissue is mediated by GPI-anchored cell wall proteins (GPI-CWPs); the corresponding genes contain long tandem repeat regions. These repeat regions resulted in assembly errors in the reference genome. Here, we performed a de novo assembly of the C. glabrata type strain CBS138 using long single-molecule real-time reads, with short read sequences (Illumina) for refinement, and constructed telomere-to-telomere assemblies of all 13 chromosomes. Our assembly has excellent agreement overall with the current reference genome, but we made substantial corrections within tandem repeat regions. Specifically, we removed 62 genes of which 45 were scrambled due to misassembly in the reference. We annotated 31 novel ORFs of which 24 ORFs are GPI-CWPs. In addition, we corrected the tandem repeat structure of an additional 21 genes. Our corrections to the genome were substantial, with the length of new genes and tandem repeat corrections amounting to approximately 3.8% of the ORFeome length. As most corrections were within the coding regions of GPI-CWP genes, our genome assembly establishes a high-quality reference set of genes and repeat structures for the functional analysis of these cell surface proteins.

Bullous systemic lupus erythematosus (BSLE) is a rare complication of systemic lupus erythematosus (SLE) characterized by cutaneous vesicles and bullae with a primarily neutrophilic infiltrate on histopathology. Bullous SLE is a heterogeneous disease without pathognomonic clinical features, making the diagnosis and differentiation from other blistering diseases challenging. We present the case of a single patient with SLE in whom 3 different clinical appearances of BSLE manifested over 5 years. The cutaneous eruption dramatically improved with rituximab at the initial presentation and continued to respond to rituximab during subsequent flares over the subsequent 5 years.

Previous structural characterizations of marsupial milk oligosaccharides have been performed in the tammar wallaby, red kangaroo, koala, common brushtail possum and the eastern quoll. To clarify the homology and heterogeneity of milk oligosaccharides among marsupial species, which could provide information on their evolution, the oligosaccharides of wombat milk carbohydrate were characterized in this study. Neutral and acidic oligosaccharides were isolated from the carbohydrate fractions of two samples of milk of the common wombat and characterized by (1) H-nuclear magnetic resonance spectroscopy. The structures of six neutral saccharides were found to be Gal(β1-4)Glc (lactose), Gal(β1-3)Gal(β1-4)Glc (3'-galactosyllactose), Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc (3',3"-digalactosyllactose), Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Gal(β1-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (galactosyl lacto-N-novopentaose I) and Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (lacto-N-novooctaose), while those of six acidic saccharides were Neu5Ac(α2-3)Gal(β1-3)Gal(β1-4)Glc. (sialyl 3'-galactosyllactose), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc (sialyl 3',3"-digalactosyllactose), Neu5Ac(α2-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose a), Gal(β1-3)[Neu5Ac(α2-3)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose c), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc,, Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc and Gal(β1-3)Gal(β1-3)[Neu5Ac(α2-3)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc. In addition, small amounts of sulfated oligosaccharides but no oligosaccharides containing Neu5Gc or α(2-6) linked Neu5Ac were detected.

Across a range of simulations with a coupled atmosphere–ocean climate model, shifts in the intertropical convergence zone (ITCZ) are induced by an interhemispheric heating contrast. The response to heating anomalies which are polar amplified are contrasted with those which are largest in the tropics. First, we find that ITCZ shifts are always damped relative to simulations in which the ocean circulation is held fixed, irrespective of the heating distribution, keeping the ITCZ “stuck” to latitudes near the equator. The damping is primarily due to the ocean’s anomalous cross-equatorial energy transport associated with the coupling of the trade winds to an oceanic cross-equatorial cell (CEC). Second, we find that the damping effect is strongest when the forcing distribution is polar-amplified, which enhances the gross stability of the CEC and maximizes the efficiency of its cross-equatorial energy transport. Third, we argue that the ocean’s energy transport can have secondary impacts on ITCZ shifts through its interaction with climate feedbacks. Finally, we discuss the implications of our study for our understanding of the role of CECs in damping ITCZ shifts and the atmosphere’s energy balance.

The establishment of a well characterized non-human primate model of Zika virus (ZIKV) infection is critical for the development of medical interventions. In this study, challenging Indian rhesus macaques (IRMs) with ZIKV strains of the Asian lineage resulted in dose-dependent peak viral loads between days 2 and 5 post infection and a robust immune response which protected the animals from homologous and heterologous re-challenge. In contrast, viremia in IRMs challenged with an African lineage strain was below the assay’s lower limit of quantitation, and the immune response was insufficient to protect from re-challenge. These results corroborate previous observations but are contrary to reports using other African strains, obviating the need for additional studies to elucidate the variables contributing to the disparities. Nonetheless, the utility of an Asian lineage ZIKV IRM model for countermeasure development was verified by vaccinating animals with a formalin inactivated reference vaccine and demonstrating sterilizing immunity against a subsequent subcutaneous challenge.