bluuebunny/crossref_metadata_2025_split huggingface dataset:
A prognostic dynamic model applicable to infectious diseases providing easily visualized guides: a case study of COVID-19 in the UK
Authors: Zhang Yuxuan , Gong Chen , Li Dawei , Wang Zhi-Wei , Pu Shengda D. , Robertson Alex W. , Yu Hong , Parrington John 
Published: April 2021

AbstractA reasonable prediction of infectious diseases’ transmission process under different disease control strategies is an important reference point for policy makers. Here we established a dynamic transmission model via Python and realized comprehensive regulation of disease control measures. We classified government interventions into three categories and introduced three parameters as descriptions for the key points in disease control, these being intraregional growth rate, interregional communication rate, and detection rate of infectors. Our simulation predicts the infection by COVID-19 in the UK would be out of control in 73 days without any interventions; at the same time, herd immunity acquisition will begin from the epicentre. After we introduced government interventions, a single intervention is effective in disease control but at huge expense, while combined interventions would be more efficient, among which, enhancing detection number is crucial in the control strategy for COVID-19. In addition, we calculated requirements for the most effective vaccination strategy based on infection numbers in a real situation. Our model was programmed with iterative algorithms, and visualized via cellular automata; it can be applied to similar epidemics in other regions if the basic parameters are inputted, and is able to synthetically mimic the effect of multiple factors in infectious disease control.
Tunable characteristics of low-frequency bandgaps in two-dimensional multivibrator phononic crystal plates under prestrain
Authors: Zhu Hai-Fei , Sun Xiao-Wei , Song Ting , Wen Xiao-Dong , Liu Xi-Xuan , Feng Jin-Shan , Liu Zi-Jiang 
Published: April 2021

AbstractIn view of the influence of variability of low-frequency noise frequency on noise prevention in real life, we present a novel two-dimensional tunable phononic crystal plate which is consisted of lead columns deposited in a silicone rubber plate with periodic holes and calculate its bandgap characteristics by finite element method. The low-frequency bandgap mechanism of the designed model is discussed simultaneously. Accordingly, the influence of geometric parameters of the phononic crystal plate on the bandgap characteristics is analyzed and the bandgap adjustability under prestretch strain is further studied. Results show that the new designed phononic crystal plate has lower bandgap starting frequency and wider bandwidth than the traditional single-sided structure, which is due to the coupling between the resonance mode of the scatterer and the long traveling wave in the matrix with the introduction of periodic holes. Applying prestretch strain to the matrix can realize active realtime control of low-frequency bandgap under slight deformation and broaden the low-frequency bandgap, which can be explained as the multiple bands tend to be flattened due to the localization degree of unit cell vibration increases with the rise of prestrain. The presented structure improves the realtime adjustability of sound isolation and vibration reduction frequency for phononic crystal in complex acoustic vibration environments.
Combined effects of crude oil exposure and warming on eggs and larvae of an arctic forage fish
Authors: Bender Morgan Lizabeth , Giebichenstein Julia , Teisrud Ragnar N. , Laurent Jennifer , Frantzen Marianne , Meador James P. , Sørensen Lisbet , Hansen Bjørn Henrik , Reinardy Helena C. , Laurel Benjamin , Nahrgang Jasmine 
Published: April 2021

AbstractClimate change, along with environmental pollution, can act synergistically on an organism to amplify adverse effects of exposure. The Arctic is undergoing profound climatic change and an increase in human activity, resulting in a heightened risk of accidental oil spills. Embryos and larvae of polar cod (Boreogadus saida), a key Arctic forage fish species, were exposed to low levels of crude oil concurrently with a 2.3 °C increase in water temperature. Here we show synergistic adverse effects of increased temperature and crude oil exposure on early life stages documented by an increased prevalence of malformations and mortality in exposed larvae. The combined effects of these stressors were most prevalent in the first feeding larval stages despite embryonic exposure, highlighting potential long-term consequences of exposure for survival, growth, and reproduction. Our findings suggest that a warmer Arctic with greater human activity will adversely impact early life stages of this circumpolar forage fish.
Ultrasensitive nucleic acid detection based on phosphorothioated hairpin-assisted isothermal amplification
Authors: Jung Yujin , Song Jayeon , Park Hyun Gyu 
Published: April 2021

AbstractHerein, we describe a phosphorothioated hairpin-assisted isothermal amplification (PHAmp) method for detection of a target nucleic acid. The hairpin probe (HP) is designed to contain a 5′ phosphorothioate (PS)-modified overhang, a target recognition site, and a 3′ self-priming (SP) region. Upon binding to the target nucleic acid, the HP opens and the SP region is rearranged to serve as a primer. The subsequent process of strand displacement DNA synthesis recycles the bound target to open another HP and produces an extended HP (EP) with a PS-DNA/DNA duplex at the end, which would be readily denatured due to its reduced thermal stability. The trigger then binds to the denatured 3′ end of the EP and is extended, producing an intermediate double-stranded (ds) DNA product (IP). The trigger also binds to the denatured 3′ end of the IP, and its extension produces the final dsDNA product along with concomitant displacement and recycling of EP. By monitoring the dsDNA products, the target nucleic acid can be identified down to 0.29 fM with a wide dynamic range from 1 nM to 1 fM yielding an excellent specificity to discriminate even a single base-mismatched target. The unique design principle could provide new insights into the development of novel isothermal amplification methods for nucleic acid detection.
Occurrence of bioluminescent and nonbioluminescent species in the littoral earthworm genus Pontodrilus
Authors: Seesamut Teerapong , Yano Daichi , Paitio José , Kin Ikuhiko , Panha Somsak , Oba Yuichi 
Published: April 2021

AbstractPontodrilus litoralis is a cosmopolitan littoral earthworm known to exhibit bioluminescence. Recently, a congeneric species, Pontodrilus longissimus, from Thailand was described. These species are sympatric, but their burrowing depths on Thai beaches are different. In this study, we examined the in vivo and in vitro bioluminescent properties of P. longissimus and P. litoralis. Mechanical stimulation induced in vivo luminescence in P. litoralis, as reported previously, but not in P. longissimus. In vitro cross-reaction tests between these species revealed the absence of luciferin and luciferase activities in P. longissimus. The coelomic fluid of P. litoralis had strong fluorescence that matched the spectral maximum of its bioluminescence, but the same result was not observed for P. longissimus. These results suggest that P. litoralis has luminescence abilities due to the creation of bioluminescent components (i.e., luciferin, luciferase, and light emitters). The presence of both luminous and nonluminous species in a single genus is likely widespread, but only a few examples have been confirmed. Our findings provide insight into the possible functions of bioluminescence in earthworms, such as avoiding predation by littoral earwigs.
The effect of age on the association between diabetes and mortality in adult patients with COVID-19 in Mexico
Authors: Woolcott Orison O. , Castilla-Bancayán Juan P. 
Published: April 2021

AbstractDiabetes is associated with severe COVID-19 and mortality. The aim of the present study was to determine the effect of age on the association between diabetes and mortality in patients with laboratory-confirmed COVID-19 in Mexico. This retrospective cohort study involved patients aged 20 years or older with symptoms of viral respiratory disease who were screened for SARS-CoV-2 infection across the System of Epidemiological Surveillance of Viral Respiratory Disease in Mexico from January 1 through November 4, 2020. Cox proportional-hazard regression was used to calculate the hazard ratio for 28-day mortality and its 95% confidence interval (CI). Among 757,210 patients with COVID-19 (outpatients and inpatients), 120,476 (16%) had diabetes and 80,616 died. Among 878,840 patients without COVID-19 (those who tested negative for SARS-CoV-2 infection), 88,235 (10.0%) had diabetes and 20,134 died. Among patients with COVID-19, diabetes was associated with a hazard ratio for death of 1.49 (95% CI 1.47–1.52), adjusting for age, sex, smoking habit, obesity, hypertension, immunodeficiency, and cardiovascular, pulmonary, and chronic renal disease. The strength of the association decreased with age (trend test: P = 0.004). For example, the adjusted hazard ratio for death was 3.12 (95% CI 2.86–3.40) for patients 20–39 years of age; in contrast, the adjusted hazard ratio of death for patients 80 years of age or older was 1.11 (95% CI 1.06–1.16). The adjusted hazard ratios were 1.66 (95% CI 1.58–1.74) in outpatients and 1.14 (95% CI 1.12–1.16) in inpatients. In hospitalized patients 80 years of age or older, no association was observed between diabetes and COVID-19-related mortality (adjusted hazard ratio: 1.03; 95% CI 0.98–1.08). Among patients without COVID-19, the adjusted hazard ratio for death was 1.78 (95% CI 1.73–1.84). In conclusion, in adult patients with COVID-19 in Mexico, the risk of death associated with diabetes decreased with age. No association between diabetes and mortality was observed among inpatients 80 years of age or older. Our findings should be verified in other populations.
One-pot thermal decomposition of commercial organometallic salt to Fe2O3@C–N and MnO@C–N for lithium storage
Authors: Wei Denghu , Xu Leilei , Jiao Ranran , Zhong Zhenlei , Ji Xiaoli , Zeng Suyuan 
Published: April 2021

Fe2O3@C–N was synthesized via a one-step thermal decomposition reaction of commercial C10H12FeN2NaO8 and used for lithium storage. The synthetic strategy can be simply extended to prepare other similar products, e.g. MnO@C–N and ZnO@C–N.
The CH radical at radio wavelengths: revisiting emission in the 3.3 GHz ground-state lines
Authors: Jacob Arshia M. , Menten Karl M. , Wiesemeyer Helmut , Ortiz-León Gisela N. 
Published: April 2021

Context. The intensities of the three widely observed radio-wavelength hyperfine structure (HFS) lines between the Λ-doublet components of the rotational ground state of CH are inconsistent with local thermodynamic equilibrium (LTE) and indicate ubiquitous population inversion. While this can be qualitatively understood assuming a pumping cycle that involves collisional excitation processes, the relative intensities of the lines and in particular the dominance of the lowest frequency satellite line are not well understood. This has limited the use of CH radio emission as a tracer of the molecular interstellar medium.
Aims. We aim to investigate the nature of the (generally) weak CH ground-state masers by employing synergies between the ground-state HFS transitions themselves and the far-infrared lines near 149 μm (2 THz) that connect these levels to the first HFS-split, rotationally excited level of the 2Π1∕2 spin–orbital manifold.
Methods. We present the first interferometric observations of the CH 9 cm ground-state HFS transitions at 3.264 GHz, 3.335 GHz, and 3.349 GHz towards the four high-mass star-forming regions (SFRs) Sgr B2 (M), G34.26+0.15, W49 (N), and W51 made with the Karl G. Jansky Very Large Array. We combine this data set with our high-spectral-resolution observations of the N, J = 2, 3∕2 → 1, 1∕2 transitions of CH near 149 μm observed towards the same sources made with the upGREAT receiver on SOFIA, which share common lower energy levels with the HFS transitions within the rotational ground state.
Results. Towards all four sources, we observe the 3.264 GHz lower satellite line in enhanced emission with a higher relative intensity than is expected at LTE, by a factor of between 4 and 20. Employing recently calculated collisional rate coefficients, we perform statistical equilibrium calculations with the non-LTE radiative-transfer code MOLPOP-CEP in order to model the excitation conditions traced by the ground-state HFS lines of CH and to infer the physical conditions in the emitting regions. The models account for effects of far-infrared line overlap with additional constraints provided by reliable column densities of CH estimated from the 149 μm lines.
Conclusions. The derived gas densities indicate that the CH radio emission lines (and the far-infrared absorption) arise from the diffuse and translucent outer regions of the envelopes of the SFRs as well as in such clouds located along the lines of sight. We infer temperatures ranging from 50 to 125 K. These elevated temperatures, together with astrochemical considerations, may indicate that CH is formed in material heated by the dissipation of interstellar turbulence, which has been invoked for other molecules. The excitation conditions we derive reproduce the observed level inversion in all three of the ground-state HFS lines of CH over a wide range of gas densities with an excitation temperature of ~−0.3 K, consistent with previous theoretical predictions.
Harnröhrenstrikturen der Frau: Aktuelles zu Diagnostik und Therapie
Authors: Kühnke Lennart , Fisch Margit , Vetterlein Malte W. 
Published: April 2021

ZusammenfassungHarnröhrenstrikturen der Frau sind ein seltenes Krankheitsbild mit individueller Symptomatik. Vor diesem Hintergrund mangelt es an klinischen Leitfäden, die sich mit Diagnostik und Therapie dieser Erkrankung befassen. Mittlerweile liegen einige Ergebnisse zu verschiedenen Operationstechniken vor, ein direkter inter-institutioneller Vergleich wird jedoch durch heterogene Patientenkohorten und kleine Fallzahlen erschwert. Die vorliegende Arbeit befasst sich mit einer aktuellen narrativen Literaturübersicht relevanter Artikel zur klinischen Diagnostik und zu den Therapiemöglichkeiten bei weiblicher Harnröhrenstriktur.Iatrogene Ursachen wie eine vorangegangene Katheterisierung oder ein urogenitaler operativer Eingriff sind die häufigsten Gründe für die Entstehung einer Harnröhrenstriktur bei der Frau. Im klinischen Alltag stellt die körperliche Untersuchung einen wichtigen Grundstein in der Differentialdiagnostik dar, um bei Verdacht auf eine anatomisch-morphologische Ursache der Harnblasenentleerungsstörung weitere diagnostische Maßnahmen (Urethrozystoskopie, Urethrographie, MRT) einzuleiten. Therapeutisch sind minimal-invasive Eingriffe wie Harnröhrenbougierungen oder Urethrotomien oftmals nur mit kurzfristigem Erfolg assoziiert, sodass die offene Harnröhrenrekonstruktion mit langfristigeren Therapieerfolgen hier eine Sonderstellung einnimmt. Zur Verfügung stehen neben offenen Harnröhrenplastiken mit gestielten Lappen aus Vaginal- oder Labialschleimhaut auch die Verwendung freier Transplantate, vor allem dem Mundschleimhaut-Autotransplantat. Aufgrund der genannten Seltenheit der Erkrankung mit nur kleinen publizierten Fallserien ist jedoch eine Beurteilung der vergleichenden Wirksamkeit der verschiedenen Techniken nur schwer möglich. Wie bei allen seltenen Erkrankungen bedarf es hier der Etablierung von multizentrischen, großen Serien, um die Standards im perioperativen Vorgehen zu verbessern.
The Promise of Youth Resistance Training
Authors: Faigenbaum Avery D , Geisler Stephan 
Published: April 2021

SummaryGlobal health reports indicate that a vast majority of children and adolescents are not accumulating the recommended amount of moderate to vigorous physical activity (MVPA) daily. This decline in MVPA has coincided with troubling temporal trends in muscular fitness in modern day youth. Since a prerequisite level of muscular strength is needed to move proficiently, developmentally appropriate interventions that target neuromuscular deficits are needed to prepare girls and boys for ongoing participation in active play, exercise and sport activities. Instead of focusing exclusively on aerobic activities, the promotion of youth physical activity should recognize the shared importance of strength, skill and aerobic activities for all youth regardless of body size or physical prowess. In addition to enhancing muscular fitness and improving motor skill performance, regular participation in resistance training has been found to have a favorable influence on musculoskeletal strength, cardiometabolic function, body composition, and mental health in children and adolescents. A new mindset that recognizes the critical importance of strength-building activities early in life is needed before this generation of girls and boys becomes resistant to exercise interventions later in life.
Statistische Signifikanz – was der p-Wert aussagt
Authors: Köppel Maximilian , Eckert Katharina ,   im Namen der AG Wissenschaft des DVGS e.V.
Published: April 2021

ZusammenfassungDer Begriff der statistischen Signifikanz geht oft mit Missverständnissen einher. Dies liegt u. a. daran, dass sich mit den theoretischen Konzepten und Kenngrößen, die hinter dem Signifikanztesten liegen, zu wenig auseinandergesetzt wird. Hierzu gehört beispielsweise der p-Wert, der aussagt, mit welcher Wahrscheinlichkeit der beobachtete oder ein extremerer Effekt gefunden würde, wenn dieser Effekt in Wirklichkeit gar nicht existieren würde. Anhand des Beispiels eines Münzwurfs soll das Konzept des Nullhypothesensignifikanztestens erläutert werden, um ein besseres Verständnis für die Interpretation von wissenschaftlichen Ergebnissen zu erzeugen.
Folgenreiche Liposuktion – was man im Umgang mit Prilocain beachten sollte
Authors: Mayer Julius Michael , Capellen Carl Ferdinand , Holzbach Thomas 
Published: April 2021

ZusammenfassungUnter der selten auftretenden erworbenen Methämoglobinämie ist die Prilocain-induzierte ätiologisch gesehen eine Rarität. Der folgende Fallbericht behandelt sie als potenziell gefährliche Komplikation nach Liposuktion mit Prilocain.Eine junge Patientin stellte sich nach präsynkopalem Sturzereignis mit blassem Hautkolorit, immobilisierendem Handgelenksschmerz und Platzwunde am Kinn in der interdisziplinären Notaufnahme vor. Etwa 12 Stunden zuvor sei bei der Patientin ambulant in Regionalanästhesie eine Liposuktion der unteren Extremität durchgeführt worden. Dabei sei ein größeres Volumen einer Tumeszenzlösung, bestehend u. a. aus Prilocain, in das Gewebe infiltriert worden.Bei initialer Vorstellung wurden ein normwertiger Blutdruck, eine leichte Tachykardie, eine periphere Sauerstoffsättigung von 90 % bei Raumluft gemessen und klinisch fielen ein reduzierter Allgemeinzustand und eine Lippenzyanose auf. Die Liposuktionszonen waren unauffällig.Die erste arterielle Blutgasanalyse zeigte einen erhöhten Methämoglobin(Met-Hb)anteil von 10,9 %. Konventionell-radiologisch ließ sich eine minimal dislozierte distale Radiusfraktur nachweisen. Unter Sauerstofftherapie fiel das Met-Hb innerhalb von 4 Stunden auf 6 %, die Lippenzyanose war rückläufig, die Vitalparameter stabilisierten sich, die Platzwunde wurde mittels primärer Wundnaht versorgt und es erfolgte eine Ruhigstellung des Handgelenks. Nach 12-stündigem Aufenthalt erfolgte die Entlassung bei gebessertem Allgemeinzustand. Sechs Wochen posttraumatisch zeigte sich eine Konsolidierung der Fraktur und funktionell-ästhetisch regelrechte Wundheilung des Kinns. Wir möchten für die Differenzialdiagnose einer Prilocain-induzierten Methämoglobinämie nach Liposuktion mit Tumeszenzlösung sensibilisieren und im Allgemeinen die Verwendung von Prilocain diskutieren.
Procoagulant Platelets: Mechanisms of Generation and Action
Authors: Podoplelova N.A. , Nechipurenko D.Y. , Ignatova A.A. , Sveshnikova A.N. , Panteleev M.A. 
Published: April 2021

AbstractDuring the past decades, it has been increasingly recognized that the major function of accelerating membrane-dependent reactions of blood coagulation is predominantly implemented by a subset of activated platelets. These procoagulant platelets (also called collagen- and thrombin-activated or COAT, coated, necrotic, although there could be subtle differences between these definitions) are uniquely characterized by both procoagulant activity and, at the same time, inactivated integrins and profibrinolytic properties. The mechanisms of their generation both in vitro and in situ have been increasingly becoming clear, suggesting unique and multidirectional roles in hemostasis and thrombosis. In this mini-review, we shall highlight the existing concepts and challenges in this field.
Effect of the Perception of Knee Pain on Muscle Strength and Endurance among Elite Female Handball Players
Authors: Kim ChanWoo , Park Ki Jun 
Published: April 2021

Abstract
Objectives This study aimed to examine the effect of knee pain perception on muscle strength and endurance among elite female handball players.
Methods This study included 60 handball players who participated in training and competition from January to December 2019. Muscle strength, endurance, and hamstring/quadriceps ratio of the knee were estimated using Computer Sports Medicine, INC (Cybex, HUMAC, USA). The independent samples t-test was used for inter-group comparison. The Pearson’s correlation and simple linear regression analyses were used to assess associations among the variables and identify factors affecting pain perception, respectively.
Results No significant differences in knee muscle strength, endurance of both the flexor and extensor muscles, and muscle strength (hamstring/quadriceps ratio) were noted between the high and low groups. However, the ratio of muscle endurance of the flexor and extensor of the knee in the high group was significantly lower than that in the low group. Furthermore, pain was found to correlate only with muscle endurance (hamstring/quadriceps ratio). The pain scale reading increased by 1. Moreover, muscle endurance ratio of the flexor and extensor muscles of the knee decreased by 3.07.
Conclusion Muscle endurance (hamstring/quadriceps ratio) of the flexor and extensor muscles, classified based on an average pain scale, differed between the high and low groups. These results can aid in development of rehabilitation and exercise programs for players involved in handball and similar sports in the future.
Radical Carbosulfonylation of Propellane: Synthesis of Sulfonyl β-Keto-bicyclo[1,1,1]pentanes
Authors: Wei Yunlong , Chen Zhiqi , Zhu Chen , Wu Zhen , Xu Yaohui , Wu Xinxin 
Published: April 2021

AbstractThe construction of multiply functionalized bicyclo[1.1.1]pentanes (BCPs) is of high synthetic value, as they are frequently harnessed as bioisosteres of 1,3-disubstituted benzene rings, alkynes, and tert-butyl groups in medicinal chemistry. Herein, we disclose a practical radical-mediated carbosulfonylation of propellane for the synthesis of sulfonyl β-keto-substituted BCPs by using vinyl sulfonates as dual-function reagent. This protocol features broad functional group tolerance and excellent atom-economy, leading to a variety of valuable difunctionalized BCP derivatives under mild photochemical conditions.
Recent Advances in C–Br Bond Formation
Authors: Yeung Ying-Yeung , Wong Jonathan 
Published: April 2021

AbstractOrganobromine compounds are extremely useful in organic synthesis. In this perspective, a focused discussion on some recent advancements in C–Br bond-forming reactions is presented.1	Introduction2	Selected Recent Advances2.1	Catalytic Asymmetric Bromopolycyclization of Olefinic Substrates2.2	Catalytic Asymmetric Intermolecular Bromination2.3	Some New Catalysts and Reagents for Bromination2.4	Catalytic Site-Selective Bromination of Aromatic Compounds2.5	sp3 C–H Bromination via Atom Transfer/Cross-Coupling3	Outlook