bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization and evolution of infection control practices among severe acute respiratory coronavirus virus 2 (SARS-CoV-2)–infected healthcare workers in acute-care hospitals and long-term care facilities in Québec, Canada, Spring 2020
Authors: Carazo Sara , Laliberté Denis , Villeneuve Jasmin , Martin Richard , Deshaies Pierre , Denis Geoffroy , Adib Georges , Tissot France , Dionne Marc , De Serres Gaston 
Published: April 2021

AbstractObjectives:In this study, we aimed to (1) estimate the severe acute respiratory coronavirus 2 (SARS-CoV-2) infection rate and the secondary attack rate among healthcare workers (HCWs) in Québec, the most affected province of Canada during the first wave; (2) describe the evolution of work-related exposures and infection prevention and control (IPC) practices in infected HCWs; and (3) compare the exposures and practices between acute-care hospitals (ACHs) and long-term care facilities (LTCFs).Design:Survey of cases.Participants:The study included Québec HCWs from private and public institutions with laboratory-confirmed coronavirus disease 2019 (COVID-19) diagnosed between March 1 and June 14, 2020. HCWs aged ≥18 years who worked during the exposure period and survived their illness were eligible for the survey.Methods:After obtaining consent, 4,542 HCWs completed a standardized questionnaire. COVID-19 rates and proportions of exposures and practices were estimated and compared between ACHs and LTCFs.Results:HCWs represented 13,726 (25%) of 54,005 reported COVID-19 cases in Québec and had an 11-times greater rate of COVID-19 than non-HCWs. Their secondary household attack rate was 30%. Most affected occupations were healthcare support workers, nurses and nurse assistants working in LTCFs (45%) and ACHs (30%). Compared to ACHs, HCWs in LTCFs had less training, higher staff mobility between working sites, similar PPE use, and better self-reported compliance with at-work physical distancing. Suboptimal IPC practices declined over time but were still present at the end of the first wave.Conclusion:Québec HCWs and their families were severely affected during the first wave of COVID-19. Insufficient pandemic preparedness and suboptimal IPC practices likely contributed to high transmission in both LTCFs and ACHs.
Job type, neighborhood prevalence, and risk of coronavirus disease 2019 (COVID-19) among healthcare workers in New York City
Authors: Ganz-Lord Fran A. , Segal Kathryn R. 
Published: April 2021

AbstractIn this study, we compared the risk of coronavirus disease 2019 (COVID-19) between clinical and nonclinical healthcare workers (HCWs) while adjusting for home ZIP codes. Clinical HCWs did not have a higher risk of COVID-19, but living in higher-risk ZIP codes was associated with increased infection rates. However, environmental services workers showed increased risk of COVID-19.
A SPARSITY RESULT FOR THE DYNAMICAL MORDELL–LANG CONJECTURE IN POSITIVE CHARACTERISTIC
Authors: GHIOCA DRAGOS , OSTAFE ALINA , SALEH SINA , SHPARLINSKI IGOR E. 
Published: April 2021

AbstractWe prove a quantitative partial result in support of the dynamical Mordell–Lang conjecture (also known as the DML conjecture) in positive characteristic. More precisely, we show the following: given a field K of characteristic p, a semiabelian variety X defined over a finite subfield of K and endowed with a regular self-map

$\Phi :X{\longrightarrow } X$
defined over K, a point

$\alpha \in X(K)$
and a subvariety

$V\subseteq X$
, then the set of all nonnegative integers n such that

$\Phi ^n(\alpha )\in V(K)$
is a union of finitely many arithmetic progressions along with a subset S with the property that there exists a positive real number A (depending only on X,

$\Phi $
,

$\alpha $
and V) such that for each positive integer M,

$$\begin{align*}\scriptsize\#\{n\in S\colon n\le M\}\le A\cdot (1+\log M)^{\dim V}.\end{align*}$$
The Threat from Within across Empires: Strikes, Labor Migration, and Violence in Central Europe, 1900–1914
Authors: Caruso Amerigo , Morelon Claire 
Published: April 2021

AbstractThe decade before the First World War saw a heightened level of social and political conflicts throughout Germany and Austria-Hungary. Strikes in pre-1914 central Europe have largely been examined as part of the development of the workers’ movement, but much less often from the perspective of the employers and government elites. Their strategies to counteract “strike terrorism” included hiring replacement workers through private strikebreaking agents, who provided a variety of services such as recruitment, transportation, housing, and providing “willing workers” with weapons for their self-defense. The discourses around “strike terrorism,” and the repressive strategies to counter it, are a lens through which we can look afresh at some of the most crucial issues in the history of central European empires in the prewar years, namely the structure of violence embedded in social conflicts, migration, growing political antagonism, and fears surrounding social democracy. This article analyzes the public debate around the protection of “willing workers” as well as concrete episodes of antilabor violence in a transnational framework. It offers a reassessment of social conflicts in the period following the 1905 social mobilizations in central Europe, and it explores the circulation of antilabor measures between Germany and Austria-Hungary, their radicalizing impact, and their connections with labor migration patterns.
On the size of the maximum of incomplete Kloosterman sums
Authors: BONOLIS DANTE 
Published: April 2021

AbstractLet $t:{\mathbb F_p} \to C$ be a complex valued function on ${\mathbb F_p}$. A classical problem in analytic number theory is bounding the maximum

$$M(t): = \mathop {\max }\limits_{0 \le H < p} \left| {{1 \over {\sqrt p }}\sum\limits_{0 \le n < H} {t(n)} } \right|$$

of the absolute value of the incomplete sums $(1/\sqrt p )\sum\nolimits_{0 \le n < H} {t(n)} $. In this very general context one of the most important results is the Pólya–Vinogradov bound

$$M(t) \le {\left\| {\hat t} \right\|_\infty }\log 3p,$$

where $\hat t:{\mathbb F_p} \to \mathbb C$ is the normalized Fourier transform of t. In this paper we provide a lower bound for certain incomplete Kloosterman sums, namely we prove that for any $\varepsilon > 0$ there exists a large subset of $a \in \mathbb F_p^ \times $ such that for $${\rm{k}}{1_{a,1,p}}:x \mapsto e((ax + \bar x)/p)$$ we have

$$M({\rm{k}}{1_{a,1,p}}) \ge \left( {{{1 - \varepsilon } \over {\sqrt 2 \pi }} + o(1)} \right)\log \log p,$$

as $p \to \infty $. Finally, we prove a result on the growth of the moments of ${\{ M({\rm{k}}{1_{a,1,p}})\} _{a \in \mathbb F_p^ \times }}$.
Surgical management of aortopulmonary window with pulmonary artery dilatation causing left main coronary compression
Authors: Mishra Anand Kumar , Hanumantacharya Naganur Sanjeev , Bansal Vidur , Rana Pratyaksha 
Published: April 2021

AbstractAortopulmonary window is a rare congenital heart defect. Left main coronary artery extrinsic compression by an enlarged pulmonary artery is a rare complication and a potential cause for chest pain and sudden cardiac death in patients with pulmonary hypertension. Here, we present the case of a 14-year-old boy with a large aortopulmonary window who was planned for a device closure, but during the procedure, he developed ST-T segment changes while the device was being deployed, and hence the procedure was abandoned. The boy subsequently underwent a successful surgical closure thereafter.
Health Care Needs in the Aftermath of Hurricane Maria in Puerto Rico: A Perspective from Federal Medical Shelter Manatí
Authors: Ghosh Arnab K. , Mecklenburg Max , Ibrahim Said , Daniel Pia 
Published: April 2021

AbstractIntroduction:On September 20, 2017, Hurricane Maria, a Category 4 hurricane, swept across Puerto Rico (PR), wreaking devastation to PR’s power, water, and health care infrastructure. To address the imminent humanitarian crisis, the US government mobilized Federal Medical Shelters (FMS) to serve the needs of hurricane victims. This study’s objective was to provide a description of the patients seeking emergency care at FMS and the changes in their needs over time.Methods:This retrospective, cross-sectional study included all patients presenting to the FMS Manatí from October 6, two weeks after Hurricane Maria’s landfall, to November 2, 2017. Categories were created to catalogue the nature of new acute medical issues by patients presenting to the Shelter. Descriptive, graphical analyses were performed to assess changes to presenting complaints over time, and by age groups defined as infant (age ≤1 years), child (1 year < age ≤10 years), adolescent (10 years < age ≤ 25 years), and adult (age > 25 years).Results:Over the 30-day period, 5,268 patients were seen in the FMS seeking medical care (average 188.1 patients per day), spending less than five hours in the facility. The distribution of patients’ age was bimodal: the first peak at one year and the second at age 50. The most common patient complaint was infection (38.8%), then musculoskeletal (MSK) complaints (11.8%) and management of chronic medical conditions (11.8%). The proportion of patients presenting with chronic disease complaints declined over the course of the period of observation (21.4% on Day 4 to 8.0% on Day 30) while the proportion of patients presenting with infection increased (31.0% on Day 4 to 48.6% on Day 30). Infection complaints were highest in all age groups, but most in infxants (80.2%), while MSK and chronic disease complaints were highest in adults (14.9% and 14.9%, respectively).Conclusion:Infection treatment and chronic disease management were important medical needs facing patients seeking care at FMS Manatí after Hurricane Maria. These findings suggest that basic needs related to sanitation and shelter remained important weeks after the hurricane, and a focus on access to medications, infection control, and injury prevention/management after a disaster needs to be prioritized during disaster response.
Multi‐Fluid MHD Simulations of Europa's Plasma Interaction Under Different Magnetospheric Conditions
Authors: Harris Camilla D. K. , Jia Xianzhe , Slavin James A. , Toth Gabor , Huang Zhenguang , Rubin Martin 
Published: April 2021

AbstractEuropa hosts a periodically changing plasma interaction driven by the variations of Jupiter's magnetic field and magnetospheric plasma. We have developed a multi‐fluid magnetohydrodynamic (MHD) model for Europa to characterize the global configuration of the plasma interaction with the moon and its tenuous atmosphere. The model solves the multi‐fluid MHD equations for electrons and three ion fluids (Jupiter's magnetospheric O+, as well as O+ and O2+ originating from Europa's atmosphere) while incorporating sources and losses in the MHD equations due to electron impact and photo‐ionization, charge exchange, recombination and other relevant collisional effects. Using input parameters constrained by the Galileo magnetic field and plasma observations, we first demonstrate the accuracy of our model by simulating the Galileo E4 and E14 flybys, which took place under different upstream conditions and sampled different regions of Europa's interaction. Our model produces 3D magnetic field and plasma bulk parameters that agree with and provide context for the flyby observations. We next present the results of a parameter study of Europa's plasma interaction at three different excursions from Jupiter's central plasma sheet, for three different global magnetospheric states, comprising nine steady‐state simulations. By separately tracking multiple ion fluids, our MHD model allows us to quantify the access of the Jovian magnetospheric plasma to Europa's surface and determine how that access is affected by changing magnetospheric conditions. We find that the thermal magnetospheric O+ precipitation rate ranges from (1.8–26) × 1024 ions/s, and that the precipitation rate increases with the density of the ambient magnetospheric plasma.
Frequency‐Dependent Rupture Characteristics of the 30 October 2016 Mw 6.5 Norcia, Italy Earthquake Inferred From Joint Multi‐Scale Slip Inversion
Authors: Liu Wei , Yao Huajian , Wei Shengji 
Published: April 2021

AbstractThe relationship between multi‐scale rupture characteristics and different frequency contents of the seismic waveforms has been revealed for moderate to great earthquakes by previous researches. To better understand such a relationship, we propose a two‐step strategy to perform finite fault inversion in the wavelet domain with multi seismic datasets, involving the seismic observations at both teleseismic and near‐field distances. In our two‐step strategy, the larger‐scale pattern of the seismic rupture is first constrained by using the lower‐frequency seismic waveforms and then based on the lower‐frequency rupture pattern, the higher‐frequency rupture features are obtained by performing inversion with higher‐frequency data. We apply this two‐step strategy with multi seismic datasets to study the 30 October 2016 Mw 6.5 Norcia, Italy earthquake, which is the largest event of the 2016–2017 central Italy seismic sequence. By analyzing the recovered slip patterns from different frequency bands, we notice the frequency‐dependent rupture features of this earthquake. The lower‐frequency slip concentrated at the shallower depths above the source, and the higher‐frequency slip appeared near the edges of the lower‐frequency slip patch, working as “barriers”, due to fault complexities in central Italy. The frequency‐dependent slip pattern of the 30 October 2016 Norcia earthquake shows a relation to the unevenly distributed pore fluid pressure, as indicated by Vp/Vs tomography from previous researches. Our results suggest that fault complexities and unevenly distributed fluids contribute to the frequency‐dependent rupture of this earthquake.
Opposite Contributions of Stationary and Traveling Planetary Waves in the Northern Hemisphere Winter Middle Atmosphere
Authors: Iwao Koki , Hirooka Toshihiko 
Published: April 2021

AbstractThis study investigates contributions of planetary waves (PWs) to the mean flow in the middle atmosphere during the Northern Hemisphere winter when PW activities are strong, by analyzing satellite data from Sounding of the Atmosphere using Broadband Emission Radiometry (SABER). It is suggested that there would be opposite contributions between easterly acceleration by monthly mean stationary planetary waves (STPWs) and westerly acceleration by remaining traveling planetary waves (TRPWs) in the high‐latitude lower mesosphere. When easterly winds appear in the mesosphere, STPWs propagating from the troposphere dissipate in the lower mesosphere to accelerate easterly winds because STPWs could not propagate in easterly wind regions. On the other hand, TRPWs develop there due to the zonal flow instability to accelerate westerly winds. The easterly wind in the mesosphere is frequently triggered by dissipation of westward TRPWs developed in the stratosphere, and would be maintained by these opposite contributions for more than 10 days. Further analyses suggest that the TRPW developing in the high‐latitude lower mesosphere would be an eastward TRPW of zonal wavenumber 1 and a period of 10–40 days. This TRPW would develop and propagate downward to dismiss the baroclinic instability by eliminating warm temperature anomalies formed below the easterly wind region due to the PW dissipation in the mesosphere.
Global Changes in Secondary Atmospheric Pollutants During the 2020 COVID‐19 Pandemic
Authors: Gaubert Benjamin , Bouarar Idir , Doumbia Thierno , Liu Yiming , Stavrakou Trissevgeni , Deroubaix Adrien , Darras Sabine , Elguindi Nellie , Granier Claire , Lacey Forrest , Müller Jean‐François , Shi Xiaoqin , Tilmes Simone , Wang Tao , Brasseur Guy P. 
Published: April 2021

AbstractWe use the global Community Earth System Model to investigate the response of secondary pollutants (ozone O3, secondary organic aerosols SOA) in different parts of the world in response to modified emissions of primary pollutants during the COVID‐19 pandemic. We quantify the respective effects of the reductions in NOx and in volatile organic carbon (VOC) emissions, which, in most cases, affect oxidants in opposite ways. Using model simulations, we show that the level of NOx has been reduced by typically 40% in China during February 2020 and by similar amounts in many areas of Europe and North America in mid‐March to mid‐April 2020, in good agreement with space and surface observations. We show that, relative to a situation in which the emission reductions are ignored and despite the calculated increase in hydroxyl and peroxy radicals, the ozone concentration increased only in a few NOx‐saturated regions (northern China, northern Europe, and the US) during the winter months of the pandemic when the titration of this molecule by NOx was reduced. In other regions, where ozone is NOx‐controlled, the concentration of ozone decreased. SOA concentrations decrease in response to the concurrent reduction in the NOx and VOC emissions. The model also shows that atmospheric meteorological anomalies produced substantial variations in the concentrations of chemical species during the pandemic. In Europe, for example, a large fraction of the ozone increase in February 2020 was associated with meteorological anomalies, while in the North China Plain, enhanced ozone concentrations resulted primarily from reduced emissions of primary pollutants.
Vertical Temperature Profile of Natural Lightning Return Strokes Derived From Optical Spectra
Authors: Boggs Levi D. , Liu Ningyu , Nag Amitabh , Walker T. Daniel , Christian Hugh J. , da Silva Caitano. L. , Austin Matthew , Aguirre Fernando , Rassoul Hamid K. 
Published: April 2021

AbstractThis study reports on spectroscopy results from a high‐speed optical spectrograph of two naturally occurring lightning return strokes. The two strokes occurred near Melbourne, FL and were from two separate flashes that were about 10 min apart and had National Lightning Detection Network (NLDN) peak currents of −19 and −63 kA. The larger peak current stroke was from a dart leader and was the last stroke in a 5 return stroke flash, while the −19 kA stroke originated from a stepped leader and was the only stroke in that flash. From the flash spectra, the return stroke channel temperature was calculated using the neutral lines of 715.7 nm (OI) and 777.4 nm (OI). In addition to the use of the neutral emission lines, the use of novel instrumentation and image processing techniques allowed the temperature to be calculated for nearly the entire visible channel (several km) and for long durations (several hundred μs). This enables temperature estimates on an unprecedented spatial and temporal scale, which show that the vertical temperature profile is not uniform across the channel. The lower altitudes are significantly hotter than higher altitudes near the time of the return stroke, with temperature gradients along the channel as large as 12,000 K/km. The rate of cooling of the channel is also initially 3–4 times larger at lower altitudes in comparison with the segments at higher altitudes. The stroke with the larger peak current shows larger maximum temperatures, larger temperature gradients along the channel, and also cools quicker.
Regionalizing Root‐Zone Soil Moisture Estimates From ESA CCI Soil Water Index Using Machine Learning and Information on Soil, Vegetation, and Climate
Authors: Grillakis Manolis G. , Koutroulis Aristeidis G. , Alexakis Dimitrios D. , Polykretis Christos , Daliakopoulos Ioannis N. 
Published: April 2021

AbstractThe European Space Agency (ESA), through the Climate Change Initiative (CCI), is currently providing nearly 4 decades of global satellite‐observed, fully homogenized soil moisture data for the uppermost 2–5 cm of the soil layer. These data are valuable as they comprise one of the most complete remotely sensed soil moisture data sets available in time and space. One main limitation of the ESA CCI soil moisture data set is the limited soil depth at which the moisture content is represented. In order to address this critical gap, we (a) estimate and calibrate the Soil Water Index using ESA CCI soil moisture against in situ observations from the International Soil Moisture Network and then (b) leverage machine learning techniques and physical soil, climate, and vegetation descriptors at a global scale to regionalize the calibration. We use this calibration to assess the root‐zone soil moisture for the period 2001–2018. The results are compared against the European Centre for Medium‐Range Weather Forecasts, ERA5 Land, and the Famine Early Warning Systems Network Land Data Assimilation System reanalyses soil moisture data sets, showing a good agreement, mainly over mid latitudes. This work contributes to the exploitation of ESA CCI soil moisture data, while the produced data can support large‐scale soil moisture‐related studies.
Polarized holographic lithography system for high-uniformity microscale patterning with periodic tunability
Authors: Xue Gaopeng , Zhai Qihang , Lu Haiou , Zhou Qian , Ni Kai , Lin Liyu , Wang Xiaohao , Li Xinghui 
Published: April 2021

AbstractPeriodic microscale array structures play an important role in diverse applications involving photonic crystals and diffraction gratings. A polarized holographic lithography system is proposed for patterning high-uniformity microscale two-dimensional crossed-grating structures with periodic tunability. Orthogonal two-axis Lloyd’s mirror interference and polarization modulation produce three sub-beams, enabling the formation of two-dimensional crossed-grating patterns with wavelength-comparable periods by a single exposure. The two-dimensional-pattern period can also be flexibly tuned by adjusting the interferometer spatial positioning. Polarization states of three sub-beams, defining the uniformity of the interference fringes, are modulated at their initial-polarization states based on a strict full polarization tracing model in a three-dimensional space. A polarization modulation model is established considering two conditions of eliminating the unexpected interference and providing the desired identical interference intensities. The proposed system is a promising approach for fabricating high-uniformity two-dimensional crossed gratings with a relatively large grating period range of 500–1500 nm. Moreover, our rapid and stable approach for patterning period-tunable two-dimensional-array microstructures with high uniformity could be applicable to other multibeam interference lithography techniques.