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Airborne lidar altimetry can measure the sea surface height (SSH) over scales ranging from hundreds of kilometers to a few meters. Here, we analyze the spectrum of SSH observations collected during an airborne lidar campaign conducted off the California coast. We show that the variance in the surface wave band can be over 20 times larger than the variance at submesoscales and that the observed SSH variability is sensitive to the directionality of surface waves. Our results support the hypothesis that there is a spectral gap between meso‐to‐submesoscale motions and small‐scale surface waves and also indicate that aliasing of surface waves into lower wavenumbers may complicate the interpretation of SSH spectra. These results highlight the importance of better understanding the contributions of different physics to the SSH variability and considering the SSH spectrum as a continuum in the context of future satellite altimetry missions. Plain Language Summary: Using unique measurements of the sea surface height (SSH) taken from an instrument onboard an airplane off the California coast, we examine how the variance of the SSH is distributed across different spatial scales, ranging from hundreds of kilometers to a few meters. We show that surface waves can be 20 times more energetic than motions with larger scales (known as submesocales) and that the direction of surface waves impacts the SSH variability depending on different sampling and averaging strategies. These results highlight the importance of better understanding the contributions of different types of motions and physics to the SSH variability. In particular, we advocate measuring scales from meters to hundreds of kilometers as a continuum to better inform future satellite altimetry missions. Key Points: We present unique broadband airborne lidar observations of sea surface height spanning scales from hundreds of kilometers to a few metersThe sea surface height variance due to surface waves can be over an order of magnitude larger than the variance at submesoscalesThe observed sea surface height is sensitive to the direction of waves which may impact the interpretation of remote sensing measurements [ABSTRACT FROM AUTHOR]

Studies over the last two decades have shown that submicron particulates (SMPs) can be transferred from the seawater into sea spray aerosol (SSA), potentially impacting SSA cloud seeding ability. This work reports the first concurrent bulk and sea surface microlayer (SSML) SMP (0.4–1.0 μm) measurements, made during two mesocosm phytoplankton blooms in a region devoid of active wave breaking and bubble formation, providing insight into how biological and physicochemical processes influence seawater SMP distributions. Modal analyses of the SMP size distributions revealed contributions from multiple, biologically related particulate populations that were controlled by the microbial loop. With negligible bubble scavenging occurring, SSML enrichment of SMPs remained low throughout both experiments, suggesting scavenging is vital for SMP enrichment in the SSML. Our findings are discussed in the context of SMP transfer into SSA and its potential importance for SSA cloud seeding ability. Plain Language Summary: Research has shown that particulates can be transferred from the ocean into sea spray aerosol (SSA) when bubbles burst at the ocean surface. This transfer is important because incorporation of seawater particulates into SSA can impact its ability to seed water and ice clouds. During the Sea Spray Chemistry and Particulate Evolution (SeaSCAPE) study, submicron particulates (SMPs, 0.4–1.0 μm) were measured daily in the sea surface microlayer (SSML), the topmost 1–1,000 μm of the ocean surface, and the underlying bulk seawater over the course of two phytoplankton growth experiments. The objective of this study was to assess the influence of biological activity on SMP concentrations and distributions in the seawater. Our results indicate that biological growth led to increased SMP production, and the size distribution of SMPs produced was dependent on the phase of the bloom growth. Additionally, almost no SSML enrichment of SMPs occurred without active wave breaking and bubble formation, highlighting the significance of biological activity and bubble scavenging/bursting for particulate transfer into SSA. These findings are discussed in the context of potential SMP impacts on SSA cloud forming ability. Key Points: The concentration of 0.4–1.0 μm seawater particulates is higher during a phytoplankton bloomThe biologically induced increase in seawater submicron particulates is size dependent and influenced by the phase of the bloomParticulate enrichment in the sea surface microlayer is low in the absence of wave breaking and bubble scavenging [ABSTRACT FROM AUTHOR]

An individual's sense of themselves as a "STEM person" is largely formed through recognition feedback. Unfortunately, for many minoritized individuals who engage in STEM (science, technology, engineering, and mathematics) in formal and informal spaces, this recognition often adheres to long‐standing exclusionary expectations of what STEM participation entails and institutionalized stereotypes of what it means to be a STEM person. However, caregivers, who necessarily share cultural backgrounds, norms, and values with their children, can play an important role in recognizing their children's interest and inclination towards STEM in ways that support children's authoring of their STEM identity in the face of these marginalizing discourses. To explore this idea, we conducted phenomenological interviews with STEM students attending a Hispanic‐serving university, examining the nature of STEM‐related conversations these students had with their parents during childhood. Participant recollections provide evidence of conversational content, contexts, and structures that supported their identification with STEM even when faced with marginalizing experiences. We found that though this phenomenon was recounted across parent profiles, participant narratives also reflected differences in conversation content, context, and structure based on factors associated with STEM stereotypes, including gender, formal education or training in STEM, and parents' immigration experiences. Viewed within larger sociocultural discourses of whose knowledge "counts" in STEM, our work suggests the need for educational institutions to acknowledge and embrace families' ability to foster youths' affinity with STEM contexts, while also recognizing and responding to institutionalized impediments to authentic STEM participation. [ABSTRACT FROM AUTHOR]

In recent decades, the eastern Pacific green turtle (recognized as the subspecies Chelonia mydas agassizii, i.e., the black turtle) has occasionally been recorded around the Japanese Archipelago. However, whether its occurrence is a recent ecological response to global climate change or a response to oceanic conditions remains unknown. In the present study, we conducted a literature search using historical Japanese natural history documents called "Honzou Gaku," and present the first record of trans‐Pacific migration of the black turtle during the Edo period (1600–1868). This finding adds substantial knowledge to our understanding of the life history of this sea turtle species. Thus, a literature search on the historical heritage of other animal and plant species could provide more information about their past or lost biodiversity. [ABSTRACT FROM AUTHOR]

A diversity of discursive formations in the vernacular flourish on the margins of history, and even outside it. To better understand these formations, particularly in postcolonial societies such as India, I argue that it is important to eschew the sole use of the lens of veracity. I explore alternative lenses through which to more fruitfully examine historical narratives in the vernacular: the contrast between the "historical past" and the "practical past," the complexities involved in cultural translation, and the lyrical and fictionalized nature of prior accounts of the past. I employ these alternative lenses to make sense of Gujarati author Nandśaṅkar Tuḷjāśaṅkar Mehtā's use of the historical novel form in his pioneering historical work, Karaṇ Ghelo, Gujarātno chello Rajpūt rājā: ek vārtā (Karaṇ the Crazy, Gujarat's Last Rajput King: A Story), the first novel written in Gujarati. Writing at a time when the demand for histories and history textbooks was burgeoning, Mehtā made the curious choice to write a vārtā, or "story"—a choice that becomes more comprehensible when seen from the alternative perspectives I propose. [ABSTRACT FROM AUTHOR]

Summary: Changes in bed topography that build and maintain channel morphology are driven by the displacements of individual particles, either though their entrainment or deposition. However, the linkages between these topographic changes and individual grain displacements have not been comprehensively addressed, as many historical tracer studies have not included coincident topographic data. In this study, we compare the movements of bedload tracers to the differences in repeat topographic surveys across four gravel‐bed river reaches. To do this, we apply a 1‐D Bayesian survival process model to the starting and ending locations of tracers. This model estimates downstream trapping probabilities, which represent the likelihood that a given segment of channel will "trap" an entrained particle. We then adapt this model to estimate downstream trapping probabilities using digital elevation models of difference and compare the results. The estimates from the tracer and topographic trapping models showed general alignment, meaning that tracers were preferentially trapped in segments that experienced deposition along the channel. Thus, tracers in this study were able to identify downstream differences in bedload transport. The comparison also highlighted that tracer‐estimated trapping probabilities were larger than topographically estimated ones. This supports previous observations that sediment travel distances estimated using tracers are shorter than those estimated using morphological methods. We find that the differences between these two estimates vary systematically across study environments. These variations are attributable to either study design (i.e., tracers being larger than the median size of the sediment that deforms the bed) or differences in compensating scour and fill. We explore potential causes for differences in compensating scour and fill, including hydrograph shape, sediment delivery regime, channel deformation style, and channel width, highlighting that morphodynamics needs to be considered in designing bedload tracer studies. [ABSTRACT FROM AUTHOR]

In the era of big data in Chemistry, the need for automated tools for virtual screening is compelling. Here, we present PrepFlow a toolkit for chemical library preparation and management. Starting from a list of compounds in SMILES or 2D molecular format, PrepFlow outputs a set of 3D molecular structures ready for use in subsequent drug discovery projects. Our development stands out for speed and robustness of execution, the efficient exploitation of HPC resources, and the implementation of an archiving strategy to save computer time, storage, and human intervention. Using a random selection of 600 compounds from available drug banks, we show that the preparation time per ligand on a desktop computer is 6.6 s. Thanks to these performances and the automatic parallelization on HPC, a chemical library of the size of ChEMBL (2 M) was prepared in around 3 days on a computer cluster. PrepFlow is freely distributed at the following link: https://ifm.chimie.unistra.fr/prepflow. [ABSTRACT FROM AUTHOR]

Periodically flooded environments in the Amazon River basin are recognized as being highly productive because of their limnological dynamics and ecological heterogeneity. They also have been historically impacted by fishery activities, therefore being crucial ecosystems to be considered in small‐scale conservation policies. Previous studies, however, did not detect or assess significant or consistent positive effects of combinations between protected areas or environmental variables on ichthyofauna. Accordingly, the present study analysed the effects of fishery management (hereafter categorization of lakes) and environmental characteristics on the attributes of fish assemblages in 20 floodplain lakes (eight categorized as open access; 12 categorized as protected lakes) inserted in a legally protected area, the Reserva de Desenvolvimento Sustentável Piagaçu‐Purus (RDS‐PP) in the lower Purus River, Amazonas State, Brazil. The results of the present study indicated depth, surface area and lake categorization synergistically influenced the ichthyofauna of these floodplain lakes. It also suggests this influence should not be treated separately in management policies. It was concluded that the potential effectiveness of fishery management in floodplain lakes is closely related to small‐scale (i.e. local) interventions, with emphasis on the role of the lakes as a unit of effective management of ichthyofauna in floodplains. Furthermore, participatory decisions during the process of elaborating management plans for floodplain lakes should consider environmental attributes relevant to biological communities and traditional knowledge. [ABSTRACT FROM AUTHOR]

Atmospheric rivers (ARs) can provide as much as 50% of the total annual rainfall to the United States West Coast via orographic precipitation. Dust is thought to enhance orographic precipitation via the "seeder‐feeder" mechanism, in which ice particles from a high cloud fall through a lower orographic cloud, seeding precipitation in the low cloud. Using the Weather Research and Forecasting model, we vary dust concentrations in simulations of two‐dimensional flow over a mountain. This idealized framework allows us to test the sensitivity of the precipitation‐dust response to a variety of different dust concentrations and initial conditions. The model is run using an ensemble of 60 radiosondes collected from Bodega Bay, CA in 2017–2018, clustered based on their vertical moisture profile into "deep moist," "shallow moist," and "subsaturated" clusters. The principle impact on precipitation is to increase the ratio of precipitation falling as snow. This produces a "spillover" effect, decreasing precipitation upwind of the peak and increasing precipitation downwind of the peak. The largest impacts on the snow/rain ratio occur at the end of the event, during cold front passage. The ensemble mean does not produce a significant seeder‐feeder response, however, in individual cases with favorable initial conditions there is a significant increase in precipitation throughout the domain due to dust effects on the seeder‐feeder mechanism. These findings afford an opportunity to build a more comprehensive understanding for the conditions under which dust aerosol can have a significant impact on precipitation during ARs, with implications for future developments in forecasting. Key Points: Dust increases the percentage of precipitation falling as snow/graupel during landfalling atmospheric riversIncreases in dust tend to decrease orographic precipitation upwind of the peak and increase orographic precipitation downwind of the peakThe sensitivity of precipitation to dust depends on the initial thermodynamic structure of the atmosphere [ABSTRACT FROM AUTHOR]

Objective: Juvenile localized scleroderma (LS) is an autoimmune disease of the skin whose pathogenesis is not well understood due to the rarity of the disease. This study was undertaken to determine the skin transcriptome in skin biopsy tissue from children with juvenile LS compared to pediatric healthy controls, with identification of significant molecular targets using RNA sequencing (RNA‐Seq). In this study, differentially expressed genes (DEGs) were assessed for correlations with histopathologic and clinical features in children with juvenile LS, and were used to group the children into distinct genetic clusters based on immunophenotype. Methods: RNA‐Seq was performed on sections of paraffin‐embedded skin tissue obtained from 28 children with juvenile LS and 10 pediatric healthy controls. RNA‐Seq was carried out using an Illumina HTS TruSeq RNA Access library prep kit, with data aligned using STAR and data analysis using a DESeq2 platform. A standardized histologic scoring system was used to score skin sections for the severity of inflammation and levels of collagen deposition. Histologic scoring was completed by 2 pathologists who were blinded with regard to the status of each sample. Spearman's rank correlation coefficients were used to assess significant correlations between DEG expression profiles and skin histologic findings in patients with juvenile LS. Results: We identified 589 significant DEGs in children with juvenile LS as compared to healthy controls. Hierarchical clustering was used to demonstrate 3 distinct juvenile LS immunophenotype clusters. The histologic scores of skin inflammation (based on numbers and categories of inflammatory cell infiltrates) were significantly correlated with the expression levels of HLA–DPB1, HLA–DQA2, HLA–DRA, and STAT1 genes (rs > 0.5, P < 0.01). Collagen thickness correlated with the expression levels of collagen organization genes as well as with genes found to be correlated with the severity of inflammation, including genes for major histocompatibility complex (MHC) class I, MHC class II, and interferon‐γ signaling. Conclusion: Among children with juvenile LS, 3 distinct genetic signatures, or clusters, were identified. In one cluster, inflammation‐related pathways were up‐regulated, corresponding to the histologic skin inflammation score. In the second cluster, fibrosis‐related pathways were up‐regulated. In the third cluster, gene expression in the skin corresponded to the patterns seen in healthy controls. Up‐regulation of HLA class II genes was observed within the first cluster (characterized by predominant inflammation), a feature that has also been observed in the peripheral blood of patients with morphea and in the skin of patients with systemic sclerosis. [ABSTRACT FROM AUTHOR]

Well‐conducted systematic reviews are invaluable for synthesising research findings. The conclusions of a review depend on how the research question was formulated, how relevant studies were found and how studies were selected for synthesis.Here, we present a practical guide for ecologists and evolutionary biologists on formulating a question for a systematic review, and finding a representative sample of research findings.We explain the steps involved using a worked example and practical training exercises. Throughout this guide we share tricks of the trade, included rules of thumb and software that we have found useful.We hope our paper helps demystify the systematic search process and encourages more researchers to adopt a systematic and reproducible approach when searching the literature. [ABSTRACT FROM AUTHOR]

Regioselective hydrofunctionalization of alkynes represents a straightforward route to access alkenyl boronate and silane building blocks. In previously reported catalytic systems, high selectivity is achieved with a limited scope of substrates and/or reagents, with general solutions lacking. Herein, we describe a selective copper‐catalyzed Markovnikov hydrofunctionalization of terminal alkynes that is facilitated by strongly donating cyclic (alkyl)(amino)carbene (CAAC) ligands. Using this method, both alkyl‐ and aryl‐substituted alkynes are coupled with a variety of boryl and silyl reagents with high α‐selectivity. The reaction is scalable, and the products are versatile intermediates that can participate in various downstream transformations. Preliminary mechanistic experiments shed light on the role of CAAC ligands in this process. [ABSTRACT FROM AUTHOR]

Natural products (NPs), being evolutionary selected over millions of years to bind to biological macromolecules, remained an important source of inspiration for medicinal chemists even after the advent of efficient drug discovery technologies such as combinatorial chemistry and high‐throughput screening. Thus, there is a strong demand for efficient and user‐friendly computational tools that allow to analyze large libraries of NPs. In this context, we introduce NP Navigator – a freely available intuitive online tool for visualization and navigation through the chemical space of NPs and NP‐like molecules. It is based on the hierarchical ensemble of generative topographic maps, featuring NPs from the COlleCtion of Open NatUral producTs (COCONUT), bioactive compounds from ChEMBL and commercially available molecules from ZINC. NP Navigator allows to efficiently analyze different aspects of NPs ‐ chemotype distribution, physicochemical properties, biological activity and commercial availability of NPs. The latter concerns not only purchasable NPs but also their close analogs that can be considered as synthetic mimetics of NPs or pseudo‐NPs. [ABSTRACT FROM AUTHOR]

Introduction: Medicinal plants have been used in healthcare since time immemorial, as have their therapeutic activities and the production of plant‐based medicines. Objectives: This study aims to use gene‐targeted molecular markers for genetic diversity analysis of 16 medicinal plants. Besides, phytochemical analysis antibacterial and antifungal activities of some medicinal plant extracts commonly used in Egypt are compared to major compounds. Methods: DNA‐based classification of 16 medicinal species using Conserved DNA‐Derived Polymorphism (CDDP) and Start Codon Targeted (SCoT) primers. Three species representing three orders (Pelargonium graveolens, Matricaria chamomilla, and Hyoscyamus muticus were analysed [high‐performance liquid chromatography (HPLC), gas chromatography‐mass spectrometry (GC‐MS)] and evaluated for their antibacterial and antifungal activities against (Escherichia coli O157: H7 ATCC 93111, Salmonella typhimurium ATCC 14028, Methicillin‐resistant Staphylococcus aureus (MRSA) ATCC 43300, Bacillus ceruse ATCC 33018, and Sclerotinia sclerotiorum in comparison with some of their antimicrobial components. Results: Our results revealed 309 and 349 polymorphic bands with 100% polymorphism. Among them, 51 and 57 were unique loci for CDDP and SCoT, respectively. The 16 species were categorised into three groups depending on the similarity matrix. The results of antibacterial and antifungal activities revealed that Pelargonium oil showed significant antifungal and antibacterial activities against the tested pathogens. Gallic acid severely reduced all tested bacteria's growth, but atropine severely reduced the growth of the B. ceruse only. Molecular modelling revealed their activity against sclerotium development. Conclusion: The gene‐targeted marker techniques were highly useful tools for the classification of the 16 medicinal plant species, despite displaying high similarities at morphological and phytochemical analyses but, have antifungal and antibacterial activities. The sixteen species were categorized into 3 groups depending on the similarity matrix. The results of antibacterial and antifungal activities revealed that Pelargonium oil showed significant antifungal and antibacterial activities against the tested pathogens. Gallic acid severely reduced all tested bacteria's growth, but Atropine severely reduced the growth of the B. ceruse only. Molecular modelling revealed their activity against sclerotium development. The gene‐targeted marker techniques were highly useful tools for the classification of the 16 medicinal plant species. [ABSTRACT FROM AUTHOR]

The Cephaloscyllium ventriosum shark is present in the artisanal fisheries of elasmobranchs on the western coast of Baja California Sur, Mexico. The main characteristics of the sexual maturation of this species based on individuals captured from off north‐west Mexico in 2013–2016 are described. The size at maturity of this species was determined for the first time (total length 82 cm for females and 76 cm for males). Most females had one egg case per one uterus, and two per one uterus was an isolated event of low incidence. From the histological analysis of females, it was possible to show sperm storage in the oviducal gland. Fully developed sperm in immature organisms were identified in the testes. The main indicator of the maturity stage of males and their mating activity is the clasper. The present study provides evidence for a reliable estimation of the sexual maturity of these organisms, demonstrating the need for the combination of macroscopic and microscopic methods. [ABSTRACT FROM AUTHOR]

The article offers suggestions on how to choose books to aid English learners with language acquisition and reading comprehension. The term English learner is used here to represent individuals who are in the process of learning English after learning a first or other language. A few essential elements to consider are: content accessibility, language accessibility, visual accessibility and genre accessibility. Considering the special needs of English learners is important in choosing books more selectively and successfully. Fiction titles that spring from the students' cultures are ideal in providing familiarity for ease of comprehension as well as for identifying with story characters. Once teachers and librarians have enhanced their library collections, they need to call students' attention to the many options available for reading and language learning. After teachers and librarians have sparked student interest, they need to provide a regular time and freedom of choice for students to enjoy the books in the library and continue to add to the collection as students' language proficiencies develop and their reading tastes mature.

The article presents the author's views on the historical development of information infrastructures and the dissemination of knowledge. The author has published a number of historical studies examining utopian schemes for managing knowledge, the evolution of institutionalized or organizational aspects of information infrastructure, and the emergence of what he thinks of as an interdiscipline. The "Universe of Information: The Work of Paul Otlet for Documentation and International Organization" was an initial study of a hitherto neglected figure. A Russian translation of this book was published in 1977 and a Spanish edition in 1996. With the advent of the Internet and the Web, it has become clear how pioneering and important historically the work of Paul Otlet and his colleagues was. It seems yet even more relevant today with the recently announced agreement between Google and a number of research libraries to digitize and make their collections available through the Web. In Information Processing and Management, "Some Schemes for Restructuring and Mobilizing Information in Documents: A Historical Perspective," the author examines the utopian information management ideas of John Dury and Samuel Hartlib.