bluuebunny/crossref_metadata_2025_split huggingface dataset:
COVID-19 Risk Factors and Mortality among Native Americans
Authors: Leggat-Barr Katherine , Uchikoshi Fumiya , Goldman Noreen 
Published: March 2021

AbstractBACKGROUNDAcademic research on the disproportionate impact of COVID-19 among Native Americans has largely been restricted to particular indigenous groups or reservations.OBJECTIVEWe estimate COVID-19 mortality for Native Americans relative to other racial/ethnic groups and explore how state-level mortality is associated with known risk factors. METHODS: We use the Standard Mortality Ratio (SMR), adjusted for age, to estimate COVID-19 mortality by racial/ethnic groups for the U.S. and 16 selected states that account for three-quarters of the Native American population. The prevalence of risk factors is derived from the American Community Survey and the Behavioral Risk Factor Surveillance System.RESULTSThe SMR for Native Americans greatly exceeds those for Black and Latino populations and varies enormously across states. There is a strong positive correlation across states between the share of Native Americans living on a reservation and the SMR. The SMR for Native Americans is highly correlated with the income-poverty ratio, the prevalence of multigenerational families, and health insurance (excluding the Indian Health Service). Risk factors associated with socioeconomic status and co-morbidities are generally more prevalent for Native Americans living on homelands, a proxy for reservation status, than for those living elsewhere.CONCLUSIONSMost risk factors for COVID-19 are disproportionately high among Native Americans. Reservation life appears to increase the risk of COVID-19 mortality.CONTRIBUTIONWe assemble and analyze a broader set of COVID-19-related risk factors for Native Americans than previous studies, a critical step toward understanding the exceptionally high COVID-19 death rates in this population.
What makes our lungs look red?
Authors: Huang Song , Lopez Cindia 
Published: March 2021

AbstractWhat makes our lungs look red? This seems to be a naÏve and trivial question. Indeed, all the textbooks tell us that what makes our body red is the presence of blood, or more precisely the red blood cells (RBC). Here we provide some experimental evidence as well arguments to prove that this belief is wrong, or only partially true. In fact, we identified an important population of red cells located outside of the blood vessels as highly compacted clusters, in the connection tissues of the lungs of several species of animals including rat and human being. These red cells possessed each a nucleus, expressing several biomarkers of different cell types such as PF4, vWF, SCF-1R, CD200R, TGF-b, etc… Interestingly, being morphologically heterogeneous, they react collectively to certain stimuli. For example, they aggregated on collagen fibers forming clusters of cells resembling that observed in vivo. The red cells may have some features of Hematopoietic Stem Cells, since they were capable of differentiating into other cell types such as alveolar macrophages. In nasal polyps, these cells formed vessel-like structures, confined within a CD31-positive tubes. Upon exposure to toxic chemicals, they formed dense networks, suggesting a possible role in coagulation. Furthermore, the number of these red cells was greatly increased in the lungs of diseased donors, especially in the lungs of CF patients. Instead of being secreted as what happens in normal red cells, vWF proteins were tethered on the cytoplasmic membrane of the red cells isolated from the lungs of CF donors, which may explain at least partially the fibrotic nature of the CF lungs.Taken together, we conclude that what makes the lungs look red is not the red blood cells, rather a distinct population of red cells, we call them Red Soma Cells (RSC). We believe that the discovery and characterization of this important population of cells will have profound theoretic as well as therapeutic implications.
Programmed mechano-chemical coupling in reaction-diffusion active matter
Authors: Senoussi Anis , Galas Jean-Christophe , Estevez-Torres André 
Published: March 2021

AbstractEmbryo morphogenesis involves a complex combination of pattern-forming mechanisms. However, classicalin vitropatterning experiments explore only one mechanism at a time, thus missing coupling effects. Here, we conjugate two major pattern-forming mechanisms —reaction-diffusion and active matter— by integrating dissipative DNA/enzyme reaction networks within an active gel composed of cytoskeletal motors and filaments. We show that the strength of the flow generated by the active gel controls the mechano-chemical coupling between the two subsystems. This property was used to engineer a synthetic material where contractions trigger chemical reaction networks both in time and space, thus mimicking key aspects of the polarization mechanism observed inC. elegansoocytes. We anticipate that reaction-diffusion active matter will promote the investigation of mechano-chemical transduction and the design of new materials with life-like properties.
Temporally distinct oscillatory codes of retention and manipulation of verbal working memory
Authors: Pavlov Yuri G. , Kotchoubey Boris 
Published: March 2021

AbstractMost psychophysiological studies of working memory (WM) target only the short-term memory construct, while short-term memory is only a part of the WM responsible for the storage of sensory information. Here, we aimed to further investigate oscillatory brain mechanisms supporting the executive components of WM – the part responsible for the manipulation of information. We conducted an exploratory reanalysis of a previously published EEG dataset where 156 participants (82 females) performed tasks requiring either simple retention or retention and manipulation of verbal information in WM. A relatively long delay period (>6s) was employed to investigate the temporal trajectory of the oscillatory brain activity. Compared to baseline, theta activity was significantly enhanced during encoding and the delay period. Alpha-band power decreased during encoding and switched to an increase in the first part of the delay before returning to the baseline in the second part; beta-band power remained below baseline during encoding and the delay. The difference between the manipulation and retention tasks in spectral power had diverse temporal trajectories in different frequency bands. The difference maintained over encoding and the first part of the delay in theta, during the first part of the delay in beta, and during the whole delay period in alpha. Our results suggest that task-related modulations in theta power co-vary with the demands on the executive control network; beta suppression during mental manipulation can be related to the activation of motor networks; alpha is likely to reflect the activation of language areas simultaneously with sensory input blockade.
Transitioning to online learning during the COVID-19 pandemic: differences in access and participation among students in disadvantaged school districts
Authors: Catalano Amy J. , Torff Bruce , Anderson Kevin S. 
Published: March 2021

PurposeThe novel coronavirus, COVID-19, which emerged in 2019 and quickly spread to the United States, resulted in widespread closure of PreK-12 schools and universities and a rapid transition to online learning. There are concerns about how students in high-needs school districts will engage with online learning, given the limited access many disadvantaged students have to Internet and computers. Accordingly, the purpose of this study is to determine teacher perceptions of students' access and participation to online learning, as well as concerns about educational outcomes among different groups of learners.Design/methodology/approachThe authors surveyed 300 K-12 teachers in NY state about the tools and accommodations they employed in their online teaching, whether their students were participating in the online learning and the reasons for their lack of participation.FindingsRespondents reported that nearly 30% of all of their students were not regularly completing their assignments. Students in high-needs districts were significantly more likely to not complete their work. Teachers reported being very concerned about their students' educational outcomes, particularly students with disabilities (SWDs) and English language learners (ELLs). Respondents also provided suggestions for improving educational access to online learning in the future.Originality/valueNo published research has yet examined student compliance in online learning during an emergency and, in particular, during this unprecedented time of the COVID-19 pandemic and months-long stay-at-home orders.
An improved imperfect maintenance strategy for multiperiod randomly failing equipment with stochastic repair times
Authors: Dellagi Sofiene , Darghouth Mohamed Noomane 
Published: March 2021

PurposeIn this paper, a maintenance strategy based on improved imperfect maintenance actions with stochastic repair times for multiperiod randomly failing equipment is developed. The main objective is to minimize the total maintenance cost by jointly finding the optimal preventive maintenance (PM) cycle and planning horizon.Design/methodology/approachA model based on the mathematical theory of reliability is developed to minimize the total maintenance cost by jointly finding the optimal couple: PM cycle T* and planning horizon H*. The proposed model aims to characterize the evolutionary impact of imperfect PM actions on the equipment failure rate and the resulting mean number of failures. The conventional threshold accepting (TA) algorithm is implemented to solve the proposed model. A numerical example for a given set of input parameters is presented in order to show the usefulness of the proposed model. A sensitivity analysis of some of the key parameters is performed to demonstrate the coherence of the developed maintenance policy.FindingsThe obtained results showed a sensitive trade-off between PM frequency and the total maintenance cost. Performing PM actions more frequently helps significantly to reduce the expected number of corrective maintenance actions and the corresponding total cost. It has also been found that improving the efficiency of the PM actions allows for maintaining the equipment less frequently by increasing the time between successive PM actions.Research limitations/implicationsGiven the complexity of the objective function to be minimized and the stochastic nature of the model's parameters, the authors limited this study to equally cyclic production periods over the planning horizon.Practical implicationsThe present model aims to provide an integrated maintenance/production comprehensive framework to assist planners in establishing maintenance schedules considering multiperiod randomly failing production systems and the evolutionary impact of imperfect PM actions on the equipment failure rate.Originality/valueContrary to the majority of existing works in the literature dealing with maintenance strategies, the authors consider that repair times are stochastic to provide a more realistic framework. In addition, the developed model considers the impact of imperfect maintenance on the equipment's mean time to failure. Thus, the evolutionary impact of imperfect PM actions on the equipment failure rate and the resulting mean number of failures is characterized. Simultaneously, the production planning horizon along with the length of each PM cycle is optimized in order to minimize the total maintenance cost over the planning horizon.
Five‐year survival with nivolumab in previously untreated Japanese patients with advanced or recurrent malignant melanoma
Authors: Uhara Hisashi , Kiyohara Yoshio , Uehara Jiro , Fujisawa Yasuhiro , Takenouchi Tatsuya , Otsuka Masaki , Uchi Hiroshi , Fukushima Satoshi , Minami Hironobu , Hatsumichi Masahiro , Yamazaki Naoya 
Published: March 2021

AbstractWe report the 5‐year follow‐up results from a single‐arm, open‐label, multicenter phase II study (ONO‐4538‐08) conducted in Japan. Twenty‐four patients with treatment‐naïve, recurrent, or unresectable stage III/IV malignant melanoma received 3 mg/kg nivolumab every 2 weeks until progressive disease or unacceptable toxicity occurred. The 5‐year overall survival (OS) rate was 26.1%. Five years after the start of nivolumab treatment, there were six survivors. The 5‐year OS rate was 66.7% for patients with a superficial spreading type, 14.3% for acral lentiginous type, and 16.7% for mucosal type. The 5‐year progression‐free survival rate was 17.2%. No new cases of partial response or complete response were observed after 3 years, and overall response and disease control rates were similar to those reported at 3 years. The treatment‐related adverse events reported between the 3‐ and 5‐year follow‐up periods were anemia (grade 2), white blood cell count decrease (grade 2), and psoriasiform dermatitis (grade 2) in one patient each. No new grade 3 or higher treatment‐related adverse events occurred in this period. In conclusion, first‐line treatment with nivolumab in Japanese patients with unresectable or metastatic melanoma resulted in confirmed long‐term survival. No new safety signals were reported in the studied population.
Early warning indicators of population collapse in a seasonal environment
Authors: Burant Joseph B. , Park Candace , Betini Gustavo S. , Norris D. Ryan 
Published: March 2021

Abstract

Recent studies have demonstrated that generic statistical signals derived from time series of population abundance and fitness‐related traits of individuals can provide reliable indicators of impending shifts in population dynamics. However, how the seasonal timing of environmental stressors influences these early warning indicators is not well understood.

The goal of this study was to experimentally assess whether the timing of stressors influences the production, detection and sensitivity of abundance‐ and trait‐based early warning indicators derived from declining populations.

In a multi‐generation, season‐specific habitat loss experiment, we exposed replicate populations of Drosophila melanogaster to one of two rates of chronic habitat loss (10% or 20% per generation) in either the breeding or the non‐breeding period. We counted population abundance at the beginning of each season, and measured body mass and activity levels in a sample of individuals at the end of each generation.

When habitat was lost during the breeding period, declining populations produced signals consistent with those documented in previous studies. Inclusion of trait‐based indicators generally improved the detection of impending population collapse. However, when habitat was lost during the non‐breeding period, the predictive capacity of these indicators was comparatively diminished.

Our results have important implications for interpreting signals in the wild because they suggest that the production and detection of early warning indicators depends on the season in which stressors occur, and that this is likely related to the capacity of populations to respond numerically the following season.
Early and systematic administration of fibrinogen concentrate in postpartum haemorrhage following vaginal delivery: the FIDEL randomised controlled trial
Authors: Ducloy‐Bouthors AS , Mercier FJ , Grouin JM , Bayoumeu F , Corouge J , Le Gouez A , Rackelboom T , Broisin F , Vial F , Luzi A , Capronnier O , Huissoud C , Mignon A ,   the FIDEL working group
Published: March 2021

ObjectiveTo assess the benefits and safety of early human fibrinogen concentrate in postpartum haemorrhage (PPH) management.DesignMulticentre, double‐blind, randomised placebo‐controlled trial. Setting: 30 French hospitals.PopulationPatients with persistent PPH after vaginal delivery requiring a switch from oxytocin to prostaglandins.MethodsWithin 30 minutes after introduction of prostaglandins, patients received either 3 g fibrinogen concentrate or placebo.Main outcome measuresFailure as composite primary efficacy endpoint: at least 4 g/dl of haemoglobin decrease and/or transfusion of at least two units of packed red blood cells within 48 hours following investigational medicinal product administration. Secondary endpoints: PPH evolution, need for haemostatic procedures and maternal morbidity–mortality within 6 ± 2 weeks after delivery.Results437 patients were included: 224 received FC and 213 placebo. At inclusion, blood loss (877 ± 346 ml) and plasma fibrinogen (4.1 ± 0.9 g/l) were similar in both groups (mean ± SD). Failure rates were 40.0% and 42.4% in the fibrinogen and placebo groups, respectively (odds ratio [OR] = 0.99) after adjustment for centre and baseline plasma fibrinogen; (95% CI 0.66–1.47; P = 0.96). No significant differences in secondary efficacy outcomes were observed. The mean plasma FG was unchanged in the Fibrinogen group and decreased by 0.56 g/l in the placebo group. No thromboembolic or other relevant adverse effects were reported in the Fibrinogen group versus two in the placebo group.ConclusionsAs previous placebo‐controlled studies findings, early and systematic administration of 3 g fibrinogen concentrate did not reduce blood loss, transfusion needs or postpartum anaemia, but did prevent plasma fibrinogen decrease without any subsequent thromboembolic events.Tweetable abstractEarly systematic blind 3 g fibrinogen infusion in PPH did not reduce anaemia or transfusion rate, reduced hypofibrinogenaemia and was safe.
Utility of non‐contrast head computed tomography in poisoned patients
Authors: McNulty Richard , Bandaranayake Lashnika , Wong Timothy , Garner Alex , Tahmid Farhan , Symes Emily , Mohammad Mohammad , Salter Mark , Gunja Naren 
Published: March 2021

AbstractObjectiveTo investigate the utility of non‐contrast head computed tomography (CT) in poisoned patients.MethodsA retrospective cohort study of patients referred to a toxicology unit between August 2010 and December 2017. Our database yielded patients who underwent head CT at presentation to the ED. Pre‐specified information was compiled from the medical records.ResultsThere were 6261 presentations of which 1142 underwent head CT (17%). Median age was 41 years, and 437 (38%) were female. There were 492 (43%) recreational ingestions and 466 (41%) deliberate self‐poisonings. The commonest agents were sedatives 376 (33%) and opioids 282 (24%); 334 (29%) cases were intubated. Signs of head injury were found in 153 cases (13%) and focal neurological signs in 68 (6%). No acute pathology was reported in 884 head CTs (77%), chronic changes in 193 (17%) and incidental findings in 26 (2%). Acute pathology was found in 39 (4%) patients: 15 with hypoxic‐ischaemic injury, three infarctions, nine with intra‐cranial haemorrhage, 11 facial bone fractures and one retro‐bulbar haematoma. No patient required an immediate surgical intervention, and only one patient had a change to clinical treatment. Acute head CT pathology was associated with at least one of the following clinical features: need for intubation, signs of head injury, seizure, headache, and unexpected neurological signs.ConclusionNon‐contrast head CT is a low‐yield investigation in patients presenting with poisoning. Consideration should be given as to whether the clinical presentation is consistent with the expected toxidrome and whether the patient would benefit from head CT.
A library preparation optimized for metagenomics of RNA viruses
Authors: Gil Patricia , Dupuy Virginie , Koual Rachid , Exbrayat Antoni , Loire Etienne , Fall Assane G. , Gimonneau Geoffrey , Biteye Biram , Talla Seck Momar , Rakotoarivony Ignace , Marie Albane , Frances Benoît , Lambert Gregory , Reveillaud Julie , Balenghien Thomas , Garros Claire , Albina Emmanuel , Eloit Marc , Gutierrez Serafin 
Published: March 2021

AbstractOur understanding of the viral communities associated to animals has not yet reached the level attained on the bacteriome. This situation is due to, among others, technical challenges in adapting metagenomics using high‐throughput sequencing to the study of RNA viromes in animals. Although important developments have been achieved in most steps of viral metagenomics, there is yet a key step that has received little attention: the library preparation. This situation differs from bacteriome studies in which developments in library preparation have largely contributed to the democratisation of metagenomics. Here, we present a library preparation optimized for metagenomics of RNA viruses from insect vectors of viral diseases. The library design allows a simple PCR‐based preparation, such as those routinely used in bacterial metabarcoding, that is adapted to shotgun sequencing as required in viral metagenomics. We first optimized our library preparation using mock viral communities and then validated a full metagenomic approach incorporating our preparation in two pilot studies with field‐caught insect vectors; one including a comparison with a published metagenomic protocol. Our approach provided a fold increase in virus‐like sequences compared to other studies, and nearly‐full genomes from new virus species. Moreover, our results suggested conserved trends in virome composition within a population of a mosquito species. Finally, the sensitivity of our approach was compared to a commercial diagnostic PCR for the detection of an arbovirus in field‐caught insect vectors. Our approach could facilitate studies on viral communities from animals and the democratization of metagenomics in community ecology of viruses.
The influence of pastoral and native forest land cover, flooding disturbance, and stream size on the trophic ecology of New Zealand streams
Authors: Fraley Kevin M. , Warburton Helen J. , Jellyman Phillip G. , Kelly Dave , McIntosh Angus R. 
Published: March 2021

AbstractDescribing trophic structure within freshwater food webs can be a useful tool for understanding relationships to make ecological inferences and to inform management action. A complementary analysis examining both stable isotope (SI) and biomass community components may be useful, because these two responses may be influenced differently by habitat factors and perturbations (e.g. flooding disturbance). To test this, stable isotope‐derived trophic height and biomass were characterised, as was coarse allochthonous, periphyton, invertebrate and fish components, for 27 stream communities in Canterbury, New Zealand. Using piecewise structural equation modelling to test relationships between components, it was found that increased catchment agricultural land cover was associated with increased periphyton biomass and δ15N (trophic height) in stream invertebrates and invertivorous fishes, likely due to nitrate runoff, but did not affect piscivorous fishes. Additionally, native forest land cover was associated with increased instream allochthonous biomass. Increased discharge (i.e. larger habitat size) did not affect the trophic height or biomass per‐unit‐area of large‐bodied piscivorous fishes (non‐native trout and native eels), although it did result in decreased biomass of small‐bodied invertivorous fishes (primarily native benthic taxa), likely due to high water velocities in larger habitats rendering habitat less suitable for small‐bodied fishes. Finally, flooding disturbance negatively affected both trophic height and biomass of large‐bodied fishes, but did not affect small‐bodied invertivorous fishes. Overall, describing stream trophic structure with complementary SI and biomass structural equation models appears to be a useful approach for constructing an integrative picture of how abiotic and biotic habitat factors affect freshwater communities. Our findings indicate that land cover, stream size and flooding disturbance should be taken into consideration by stream managers when conducting habitat restoration efforts or setting fish harvest regulations.