bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coronavirus disease 2019 (COVID-19) vaccine hesitancy among physicians, physician assistants, nurse practitioners, and nurses in two academic hospitals in Philadelphia
Authors: Browne Safa K. , Feemster Kristen A. , Shen Angela K. , Green-McKenzie Judith , Momplaisir Florence M. , Faig Walter , Offit Paul A. , Kuter Barbara J. 
Published: September 2021

AbstractObjective:To evaluate coronavirus disease 2019 (COVID-19) vaccine hesitancy among healthcare personnel (HCP) with significant clinical exposure to COVID-19 at 2 large, academic hospitals in Philadelphia, Pennsylvania.Design, setting, and participants:HCP were surveyed in November–December 2020 about their intention to receive the COVID-19 vaccine.Methods:The survey measured the intent among HCP to receive a COVID-19 vaccine, timing of vaccination, and reasons for or against vaccination. Among patient-facing HCP, multivariate regression evaluated the associations between healthcare positions (medical doctor, nurse practitioner or physician assistant, and registered nurse) and vaccine hesitancy (intending to decline, delay, or were unsure about vaccination), adjusting for demographic characteristics, reasons why or why not to receive the vaccine, and prior receipt of routine vaccines.Results:Among 5,929 HCP (2,253 medical doctors [MDs] and doctors of osteopathy [DOs], 582 nurse practitioners [NPs], 158 physician assistants [PAs], and 2,936 nurses), a higher proportion of nurses (47.3%) were COVID-vaccine hesitant compared with 30.0% of PAs and NPs and 13.1% of MDs and DOs. The most common reasons for vaccine hesitancy included concerns about side effects, the newness of the vaccines, and lack of vaccine knowledge. Regardless of position, Black HCP were more hesitant than White HCP (odds ratio [OR], ∼5) and females were more hesitant than males (OR, ∼2).Conclusions:Although most clinical HCP intended to receive a COVID-19 vaccine, intention varied by healthcare position. Consistent with other studies, hesitancy was also significantly associated with race or ethnicity across all positions. These results highlight the importance of understanding and effectively addressing reasons for hesitancy, especially among frontline HCP who are at increased risk of COVID exposure and play a critical role in recommending vaccines to patients.
Separable and semiparametric network-based counting processes applied to the international combat aircraft trades
Authors: Fritz Cornelius , Thurner Paul W. , Kauermann Göran 
Published: September 2021

AbstractWe propose a novel tie-oriented model for longitudinal event network data. The generating mechanism is assumed to be a multivariate Poisson process that governs theonsetandrepetitionof yearly observed events with two separate intensity functions. We apply the model to a network obtained from the yearly dyadic number of international deliveries of combat aircraft trades between 1950 and 2017. Based on the trade gravity approach, we identify economic and political factors impeding or promoting the number of transfers. Extensive dynamics as well as country heterogeneities require the specification of semiparametric time-varying effects as well as random effects. Our findings reveal strong heterogeneous as well as time-varying effects of endogenous and exogenous covariates on theonsetandrepetitionof aircraft trade events.
The sentence repetition task as a measure of sign language proficiency
Authors: Schönström Krister , Hauser Peter C. 
Published: September 2021

AbstractSign language research is important for our understanding of languages in general and for the impact it has on policy and on the lives of deaf people. There is a need for a sign language proficiency measure, to use as a grouping or continuous variable, both in psycholinguistics and in other sign language research. This article describes the development of a Swedish Sign Language Sentence Repetition Test (STS-SRT) and the evidence that supports the validity of the test’s interpretation and use. The STS-SRT was administered to 44 deaf adults and children, and was shown to have excellent internal reliability (Cronbach’s alpha of 0.915) and inter-rater reliability (Intraclass Correlation Coefficient [ICC] = 0.900, p < .001). A linear mixed model analysis revealed that adults scored 20.2% higher than children, and delayed sign language acquisition were associated with lower scores. As the sign span of sentences increased, participants relied on their implicit linguistic knowledge to scaffold their sentence repetitions beyond rote memory. The results provide reliability and validity evidence to support the use of STS-SRT in research as a measure of STS proficiency.
An improved minimal error model for the robotic kinematic calibration based on the POE formula
Authors: Luo Ruiqing , Gao Wenbin , Huang Qi , Zhang Yi 
Published: September 2021

SummaryThe conventional product of exponentials
$\left(\rm POE\right)$
-based methods dissatisfy the parametric minimality for the kinematic calibration of serial robots due to overlooking the magnitude and pitch constraints. Thus, the minimal kinematic model is presented to solve this problem, which can be developed further. This paper puts forward an improved algorithm for the minimal parameter calibration. An actual kinematic model with the minimal parameters
$\left(\rm MP\right)$
is constructed according to the geometric properties of actual joint twists in the auxiliary frames established on the basis of the nominal joint axes. Then, the initial pose error is defined in the tool coordinate frame, which is expressed as the exponential map of the twist, and all twist descriptions are unified, so as to give a unified kinematic model in mathematics. By differentiating the kinematic model, a minimal error model is derived in explicit form. Subsequently, we propose a novel parameter identification method, which identifies the orientation error and position error parameters separately by the iterative least-squares method and updates the MP uniformly. Finally, the simulations and experiments on the different serial robots are conducted to verify the correctness and effectiveness of the proposed algorithm. The simulation results show our calibration algorithm outperforms the existing ones in the accuracy aspect, and the experiment result shows that the absolute pose accuracy of the UR5 industrial robot is upgraded about 9 times under a statistics sense after the calibration.
Periphyton diversity in two different Antarctic lakes assessed using metabarcoding
Authors: Câmara Paulo E.A.S. , De Souza Láuren M.D. , Pinto Otávio Henrique Bezerra , Convey Peter , Amorim Eduardo T. , Carvalho-Silva Micheline , Rosa Luiz Henrique 
Published: September 2021

AbstractAntarctic lakes have generally simple periphyton communities when compared with those of lower latitudes. To date, assessment of microbial diversity in Antarctica has relied heavily on traditional direct observation and cultivation methods. In this study, sterilized cotton baits were left submerged for two years in two lakes on King George Island and Deception Island, South Shetland Islands (Maritime Antarctic), followed by assessment of diversity by metabarcoding using high-throughput sequencing. DNA sequences of 44 taxa belonging to four kingdoms and seven phyla were found. Thirty-six taxa were detected in Hennequin Lake on King George Island and 20 taxa were detected in Soto Lake on Deception Island. However, no significant difference in species composition was detected between the two assemblages (Shannon index). Our data suggest that metabarcoding provides a suitable method for the assessment of periphyton biodiversity in oligotrophic Antarctic lakes.
Use of an experimental design to optimise the saponification reaction and the quantification of vitamins A1 and A2 in whole fish
Authors: Sroy Sengly , Servent Adrien , Sriwichai Wichien , In Sokneang , Avallone Sylvie 
Published: September 2021

Abstract: In ASEAN countries, small freshwater fish species contribute to the nutritional needs of people with few livelihoods by providing them with significant amounts of protein, fat, vitamins and minerals. Some species are eaten whole (with their organs, skin, bones, head and eyes). To estimate the vitamin A content of these foods, conventional saponification has been applied but has not been able to fully release the retinol. Our objective was to optimise the conditions of vitamin A saponification in whole fish to have a reliable estimate of their contribution to intakes. The effects of temperature and saponification time on the retinol quantification of whole fish were evaluated using a two-factor experimental design. Reaction time had a significant effect on the saponification of standard retinyl palmitate and whole fish (p≤0.05). For whole fish, the best conditions for the saponification were to heat the samples to 80 °C for 43 minutes. Under these conditions, the retinol is well liberated from the matrix and protected from degradation and isomerisation reactions. The time-temperature couple used is more intense than that recommended for quantifying vitamin A in milk or enriched margarines. The protective effect of the food matrix against the release of retinol is evident. Vitamin A2 alcohol (3,4-didehydroretinol) was detected in five species and the overall vitamin A contents ranged from 9.6 to 737.5 μg RE/100 g in species frequently consumed in Cambodia. The two species of small fish consumed whole were the ones that contained significantly more vitamin A among the ten tested (p≤0.05). Highlights: Vitamin A2 alcohol was quantified in five fish species. The official saponification partially released retinol in whole fish. The optimised reaction required heating the sample to 80 °C for 43 min.
Process‐Based Flood Risk Assessment for Germany
Authors: Sairam Nivedita , Brill Fabio , Sieg Tobias , Farrag Mostafa , Kellermann Patric , Nguyen Viet Dung , Lüdtke Stefan , Merz Bruno , Schröter Kai , Vorogushyn Sergiy , Kreibich Heidi 
Published: September 2021

AbstractLarge‐scale flood risk assessments are crucial for decision making, especially with respect to new flood defense schemes, adaptation planning and estimating insurance premiums. We apply the process‐based Regional Flood Model (RFM) to simulate a 5000‐year flood event catalog for all major catchments in Germany and derive risk curves based on the losses per economic sector. The RFM uses a continuous process simulation including a multisite, multivariate weather generator, a hydrological model considering heterogeneous catchment processes, a coupled 1D–2D hydrodynamic model considering dike overtopping and hinterland storage, spatially explicit sector‐wise exposure data and empirical multi‐variable loss models calibrated for Germany. For all components, uncertainties in the data and models are estimated. We estimate the median Expected Annual Damage (EAD) and Value at Risk at 99.5% confidence for Germany to be €0.529 bn and €8.865 bn, respectively. The commercial sector dominates by making about 60% of the total risk, followed by the residential sector. The agriculture sector gets affected by small return period floods and only contributes to less than 3% to the total risk. The overall EAD is comparable to other large‐scale estimates. However, the estimation of losses for specific return periods is substantially improved. The spatial consistency of the risk estimates avoids the large overestimation of losses for rare events that is common in other large‐scale assessments with homogeneous return periods. Thus, the process‐based, spatially consistent flood risk assessment by RFM is an important step forward and will serve as a benchmark for future German‐wide flood risk assessments.
Canadian Arctic Archipelago Shelf‐Ocean Interactions: A Major Iron Source to Pacific Derived Waters Transiting to the Atlantic
Authors: Colombo Manuel , Rogalla Birgit , Li Jingxuan , Allen Susan E. , Orians Kristin J. , Maldonado Maria T. 
Published: September 2021

AbstractContinental shelves are important sources of iron (Fe) in the land‐dominated Arctic Ocean. To understand the export of Fe from the Arctic to Baffin Bay (BB) and the North Atlantic, we studied the alteration of the Fe signature in waters transiting the Canadian Arctic Archipelago (CAA). During its transit through the CAA, inflowing Arctic Waters from the Canada Basin become enriched in Fe as result of strong sediment resuspension and enhanced sediment‐water interactions (non‐reductive dissolution). These high Fe waters are exported to BB, where approximately 10.7 kt of Fe are delivered yearly from Lancaster Sound. Furthermore, if the two remaining main CAA pathways (Jones Sound and Nares Strait) are included, this shelf environment would be a dominant source term of Fe (dFe + pFe: 26–90 kt y−1) to Baffin Bay. The conservative Fe flux estimate (26 kt y−1) is 1.7–38 times greater than atmospheric inputs, and may be crucial in supporting primary production and nitrogen fixation in BB and beyond.
Scale‐Bridging in Three‐Dimensional Fracture Networks: Characterizing the Effects of Variable Fracture Apertures on Network‐Scale Flow Channelization
Authors: Hyman Jeffrey D. , Sweeney Matthew R. , Frash Luke P. , Carey J. William , Viswanathan Hari S. 
Published: September 2021

AbstractWe incorporate observations of real fracture aperture variability observed in laboratory experiments into an ensemble of three‐dimensional discrete fracture network (DFN) simulations to characterize how variations of this micro‐scale feature can influence flow and transport behavior at the network scale. A shear fracture is created within a Marcellus shale sample, and the fracture aperture is measured using a triaxial direct‐shear device coupled with real‐time X‐ray imaging at in‐situ stress conditions. We construct an ensemble of fracture networks based on natural fractures in Marcellus shale and project regions of the experimental aperture field onto each fracture in the networks. Our calculations demonstrate that the degree of flow channelization, a network‐scale flow field structure, is dramatically increased by local changes in the aperture field that in turn affects flow and transport properties.
Limited Carbon Cycle Response to Increased Sulfide Weathering Due to Oxygen Feedback
Authors: Maffre Pierre , Swanson‐Hysell Nicholas L. , Goddéris Yves 
Published: September 2021

AbstractThe chemical weathering of sulfide‐bearing rocks can result in the dissolution of carbonate rocks leading to degassing of to the atmosphere. While this process has been argued to be a significant geologic source of , it also perturbs the geological cycles of oxygen and sulfur, triggering a cascade of geochemical feedbacks. Using a numerical model of geochemical cycles and climate, we found that due to feedbacks on atmospheric oxygen associated with the organic carbon cycle, an increase of sulfide weathering leads to a limited source of followed by a longer sink of . This result is due to the stoichiometry of sulfide weathering where more is consumed than is released. If sulfide weathering increases progressively on a geological timescale, the duration of the carbon source is extended, but its magnitude is negligible before it becomes a carbon sink.
Kinetic‐Scale Magnetic Holes Inside Foreshock Transients
Authors: Liu Terry Z. , Zhang Hui , Turner Drew L. , Goodrich Katherine A. , An Xin , Zhang Xiaojia 
Published: September 2021

AbstractIn Earth’s foreshock, there are many foreshock transients that have core regions with low field strength, low density, high temperature, and bulk velocity variation. Through dynamic pressure perturbations, they can disturb the magnetosphere–ionosphere system. They can also accelerate particles contributing to particle acceleration at the bow shock. Recent Magnetospheric Multiscale (MMS) mission observations showed that inside the low field strength core region, there are usually kinetic‐scale magnetic holes with even lower field strength (<1 nT). However, their nature and effects are unknown. In this study, we used MMS observations to conduct case studies on these magnetic holes. We found that they could be subion‐scale current sheets without a magnetic normal component and guide field, driven by the motion of demagnetized electrons. These magnetic holes can also be subion‐scale flux ropes or magnetic helical structures with weak axial field. The low field strength inside them can be either driven by external expansion or electron mirror mode. Electrons inside them show flux depletion at 90° pitch angle resulting in an “electron hole” distribution. These magnetic holes can play a role in electron dynamics, wave excitation, and shaping the foreshock transient structures. Our detailed study of such features sheds light on the turbulent nature of foreshock transient cores.
Phosphorus Chemistry in the Earth's Upper Atmosphere
Authors: Plane John M. C. , Feng Wuhu , Douglas Kevin M. 
Published: September 2021

AbstractThe ablation of phosphorus from interplanetary dust particles entering the Earth's atmosphere is a potentially significant source of this key bioelement. In this study, the atmospheric chemistry of phosphorus is explored by developing a reaction network of possible routes from PO, the major ablation product in the upper mesosphere/lower thermosphere region, to the stable reservoirs H3PO3 and H3PO4 that become incorporated into meteoric smoke particles (MSPs) as metal phosphites and phosphates, respectively. The network is constructed with reactions whose kinetics have been measured experimentally, together with reactions where theoretical rate coefficients are estimated using a combination of electronic structure theory calculations and a Rice‐Ramsperger‐Kassel‐Markus master equation treatment. The network is then incorporated into a global chemistry‐climate model, together with a phosphorus meteoric input function. The estimated global mean P deposition flux, in the form of submicron‐sized MSPs, is 1 × 10−8 g m−2 yr−1, with a maximum of ∼5 × 10−8 g m−2 yr−1 over the northern Rockies, Himalayas, and southern Andes. The estimated fraction of ablated phosphorus forming bioavailable metal phosphites is 11%, which results from the very large concentrations of O and H compared to OH in the upper mesosphere. A layer of OPO is predicted to occur at 90 km with a peak of concentration of ∼50 cm−3; this is the counterpart of the well‐known layers of meteoric metals such as Na and Fe, and may be observable spectroscopically.
Key Factors Determining Heterogeneous Uptake Kinetics of NO2 Onto Alumina: Implication for the Linkage Between Laboratory Work and Modeling Study
Authors: Gao Xiaoyan , Zhong Cheng , Tang Mingjin , Ma Qingxin , Liu Chang 
Published: September 2021

AbstractHeterogeneous reactions on mineral dust play pivotal roles in the removal/production of gaseous pollutants and the formation of secondary particles. However, the uptake coefficient (γ), a key kinetic parameter for a heterogeneous reaction, could vary by several orders of magnitude in different laboratory analyses and give rise to great uncertainties in modeling studies. Thus, a detailed understanding of heterogeneous uptake kinetics is vital to accurately evaluate the impacts of heterogeneous reactions on atmospheric chemistry. In order to reveal the key factors affecting uptake kinetics, heterogeneous reaction of NO2 on surfaces of typical mineral component alumina (α‐Al2O3, γ‐Al2O3, δ‐Al2O3, and AlOOH) was comprehensively studied using two widely used methods, including diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and flow tube reactor. The discrepancy between the true uptake coefficients (γBET) obtained via two techniques was within 1–2 orders of magnitude for alumina samples. The γBET depended positively on NO2 concentration in the DRIFTS measurements but negatively on NO2 concentration in the flow tube experiments, and the discrepancy might be attributed to different calculation methods of γBET, which was calculated based on nitrate formation kinetics in DRIFTS experiments while based on NO2 consumption kinetics in flow tube experiments. The results implied that an accurate selection of the uptake coefficient for modeling studies should base on the consideration of factors such as the measurement method, the concentration range of the reaction gas, and the characteristics of the sample such as crystal structure and effective surface area.
Loss of Ice Cover, Shifting Phenology, and More Extreme Events in Northern Hemisphere Lakes
Authors: Sharma Sapna , Richardson David C. , Woolway R. Iestyn , Imrit M. Arshad , Bouffard Damien , Blagrave Kevin , Daly Julia , Filazzola Alessandro , Granin Nikolay , Korhonen Johanna , Magnuson John , Marszelewski Włodzimierz , Matsuzaki Shin‐Ichiro S. , Perry William , Robertson Dale M. , Rudstam Lars G. , Weyhenmeyer Gesa A. , Yao Huaxia 
Published: September 2021

AbstractLong‐term lake ice phenological records from around the Northern Hemisphere provide unique sensitive indicators of climatic variations, even prior to the existence of physical meteorological measurement stations. Here, we updated ice phenology records for 60 lakes with time‐series ranging from 107–204 years to provide the first re‐assessment of Northern Hemispheric ice trends since 2004 by adding 15 additional years of ice phenology records and 40 lakes to our study. We found that, on average, ice‐on was 11.0 days later, ice‐off was 6.8 days earlier, and ice duration was 17.0 days shorter per century over the entire record for each lake. Trends in ice‐on and ice duration were six times faster in the last 25‐year period (1992–2016) than previous quarter centuries. More extreme events in recent decades, including late ice‐on, early ice‐off, shorter periods of ice cover, or no ice cover at all, contribute to the increasing rate of lake ice loss. Reductions in greenhouse gas emissions could limit increases in air temperature and abate losses in lake ice cover that would subsequently limit ecological, cultural, and socioeconomic consequences, such as increased evaporation rates, warmer water temperatures, degraded water quality, and the formation of toxic algal blooms.
Seasonality of Recharge Drives Spatial and Temporal Nitrate Removal in a Karst Conduit as Evidenced by Nitrogen Isotope Modeling
Authors: Husic Admin , Fox James , Al Aamery Nabil , Ford William , Pollock Erik , Backus Jason 
Published: September 2021

AbstractNitrogen removal rates can vary with time, space, and external environmental drivers, but are underreported for karst environments. We carried out a multi‐year study of a karst conduit where we: (a) measured inputs and outputs of sediment nitrogen (SN and δ15NSed) and nitrate (NO3− and δ15NNO3); (b) developed, calibrated, and applied a numerical model of nitrogen physics and biogeochemistry; and (c) forecasted the impacts of climate and land use changes on nitrate removal and export. Data results from conduit inputs (SN = 0.43% ± 0.07%, δ15NSed = 5.07‰ ± 1.01‰) and outputs (SN = 0.36% ± 0.09%, δ15NSed = 6.45‰ ± 0.71‰) indicate net‐mineralization of SN and increase of δ15NSed (p < 10−2). However, δ15NSed increase cannot be explained by SN mineralization alone and is instead accompanied by immobilization of isotopically heavier mineral nitrogen (δ15NNO3 = 11.25‰ ± 6.96‰). Modeled SN and δ15NSed sub‐routines provided a boundary condition for DIN simulation and improved NO3− model performance (from NSE = 0.06 to NSE = 0.68). Modeled spatial zones of removal occur in close proximity to conduit entrances, where deposition of labile organic matter promotes a three‐fold increase in denitrification (∼60 mg N m−2 d−1). Modeled temporal periods of removal occur during the dry‐season where longer residence times cause up to 90% removal of NO3− inputs. Projected effects of environmental drivers suggest an increase in denitrification (+14.1%); however, this removal is largely offset by greater nitrate soil leaching (+28.1%) from wetter regional climate. Results suggest that conduits underlying mature karst terrain experience spatiotemporal removal gradients, which are modulated by solute and sediment delivery.