bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estimating survival of unmarked neonates with camera traps
Authors: Horne Jon S. , Thompson Sarah J. 
Published: June 2021

AbstractSurvival and recruitment of offspring are important drivers of population dynamics. Yet, studying wildlife shortly after parturition is logistically challenging and oftentimes cost‐prohibitive. As a result, our ecological understanding of neonate survival is limited for many species and management decisions are often made without an adequate understanding of their implications. We developed a model to estimate the overall survival rate of neonates and the timing of mortality (i.e., shape of the survival curve) based on changes in the ratio of neonates to adult females observed in camera trap photographs. We evaluated the model with simulations and provided an example application using North American elk (Cervus canadensis) in Idaho. Our simulations suggested that estimates of the overall neonate survival rate and the shape of the survival curve are accurate when researchers provide unbiased estimates of adult female survival, birth rate (offspring per adult female), and the distribution of birth dates. When researchers can provide a priori values for just adult female survival and birth rate, estimates of the overall survival rate were accurate, but early neonate mortality was underestimated. Our estimate of neonate elk survival in Idaho was consistent with values generated by capture‐based studies. Our ratio‐based model provides an alternative to traditional methods for estimating neonate survival and does not rely on invasive or expensive capture and monitoring techniques. We believe this method could apply to a wide variety of species due to the ease of data collection and the relatively small number of critical model assumptions. A major benefit of our model is the ability to simultaneously monitor other species in the community, which will facilitate a better understanding of drivers of variation in neonate survival.
Hippopotamus movements structure the spatiotemporal dynamics of an active anthrax outbreak
Authors: Stears Keenan , Schmitt Melissa H. , Turner Wendy C. , McCauley Douglas J. , Muse Epaphras A. , Kiwango Halima , Mathayo Daniel , Mutayoba Benezeth M. 
Published: June 2021

AbstractGlobally, anthrax outbreaks pose a serious threat to people, livestock, and wildlife. Furthermore, environmental change can exacerbate these outbreak dynamics by altering the host–pathogen relationship. However, little is known about how the quantitative spatial dynamics of host movement and environmental change may affect the spread of Bacillus anthracis, the causative agent of anthrax. Here, we use real‐time observations and high‐resolution tracking data from a population of common hippopotamus (Hippopotamus amphibius) in Tanzania to explore the relationship between river hydrology, H. amphibius movement, and the spatiotemporal dynamics of an active anthrax outbreak. We found that extreme river drying, a consequence of anthropogenic disturbances to our study river, indirectly facilitated the spread of B. anthracis by modulating H. amphibius movements. Our findings reveal that anthrax spread upstream in the Great Ruaha River (~3.5 km over a 9‐day period), which followed the movement patterns of infected H. amphibius, who moved upstream as the river dried in search of remaining aquatic refugia. These upstream movements can result in large aggregations of H. amphibius. However, despite these aggregations, the density of H. amphibius in river pools did not influence the number of B. anthracis‐induced mortalities. Moreover, infection by B. anthracis did not appear to influence H. amphibius movement behaviors, which suggests that infected individuals can vector B. anthracis over large distances right up until their death. Finally, we show that contact rates between H. amphibius‐ and B. anthracis‐infected river pools are highly variable and the frequency and duration of contacts could potentially increase the probability of mortality. While difficult to obtain, the quantitative insights that we gathered during a real‐time anthrax outbreak are critical to better understand, predict, and manage future outbreaks.
Efficient Homogeneous Hydridoirida‐β‐Diketone‐Catalyzed Methanolysis of Ammonia‐Borane for Hydrogen Release in Air. Mechanistic Insights
Authors: Bustos Itxaso , Freixa Zoraida , Pazos Ariadna , Mendicute‐Fierro Claudio , Garralda María A. 
Published: June 2021

AbstractThe hydridoirida‐β‐diketone [(IrH{(PPh2(o‐C6H4CO))2H})2(μ‐Cl)][BF4] (2) has been used as a homogeneous catalyst for the methanolysis of ammonia‐borane to release up to 3 equivalents of hydrogen in the presence of air. With catalyst loadings as low as 0.2 mol%, ammonia‐borane undergoes methanolysis within 6 min at 30 °C, with TOF50% of 320 molH2 ⋅ molIr−1 ⋅ min−1, or within 80 s at 60 °C, with an excellent TOF50% of 1991 molH2 ⋅ molIr−1 ⋅ min−1, and maintains its catalytic activity in consecutive runs. Triethylamine‐borane fails to undergo methanolysis. Kinetic studies indicate first‐order dependence on substrate and on catalyst concentration and suggest cleavage of the solvent O−H bond being involved in the rate determining step of the reaction. In methanol solution 2 forms cationic [IrH(MeOH){(PPh2(o‐C6H4CO))2H}]+ (3) and reacts with Me3N−BH3 to afford a hydridoirida‐β‐diketone [IrH(Me3NBH3){(PPh2(o‐C6H4CO))2H}]+ (4), with the borane adduct η1‐coordinated to iridium. Compound [4][BArF4] shows dynamic behaviour in solution due to exchange of bridging and terminal B−H bonds. A multinuclear NMR study of the catalyzed reaction shows the formation of two ammonia‐methoxyborane adduct intermediates, H3N−BH2(OCH3) and H3N−BH(OCH3)2, and an iridium species proposed of the hydridodiacyl type [IrH(H3NBH3−x(OCH3)x)(PPh2(o‐C6H4CO))2] with a coordinated borane adduct. On account of experimental evidence, a simplified catalytic cycle is suggested for the methanolysis of AB to release hydrogen.
Diaminoterephthalate‐EDTA and ‐EGTA Conjugates – “Turn on” Fluorescence Sensors for Zinc Ions
Authors: Schröder Nils , Schmidtmann Marc , Christoffers Jens 
Published: June 2021

AbstractA highly effective “turn‐on” fluorescence sensor with high selectivity for Zn2+ ions is reported. Its constitution simply consists of two units of the fluorescence dye diaminoterephthalate (DAT) and the chelate ligand EDTA. In total, four products (DAT)2EDTA and (DAT)2EGTA were prepared by conjugation of DATs with chelate ligands EDTA and EGTA as sensors for metal ions in solution. The fluorescence of all four compounds is strongly quenched by coordination of Cu2+ and Ni2+ ions. For one EDTA‐derivative, the fluorescence quantum yield is increased by the factor of five with ten equivalents of ScCl3. For both EDTA derivatives, the fluorescence quantum yield increased by the factor of five with one equivalent Zn(OAc)2. Therefore, the (DAT)2EDTA structures constitute fluorescence sensors with a high selectivity for Zn2+ accompanied by a strong “turn‐on” effect with Zn2+ ions. Furthermore, the coordination geometry of (DAT)2EDTA with Zn2+ was elucidated by X‐ray single crystal structure analysis of the trinuclear complex [ZnCl2]{Zn(OH2)[(DAT)2EDTA – 2 H]}2 ⋅ 6.5 H2O.
Modeling the duration and size of wildfires using joint mixture models
Authors: Xi Dexen D. Z. , Dean Charmaine B. , Taylor Stephen W. 
Published: June 2021

AbstractFire duration and fire size are key outcomes for quantifying the survivorship of extended attack fires, here considered to be fires with duration greater than 2 days and size greater than 4 ha. Past studies suggest that these key outcomes are correlated. As well, fire behavior, linked to hidden effects, tends to yield that fires arise from different subpopulations. Indeed, it is not unusual for fire behavior to be identified as arising from normal or extreme subpopulations, for example. Here, we embed these two concepts into a new framework for jointly modeling fire duration and fire size. We develop a bivariate finite mixture framework that can be used to model duration and size with four subpopulations of the outcomes whereby duration and size are either normal or extreme. We utilize a shared random effect model as well as a bivariate Gaussian mixture model for such mixture modeling. We also incorporate the effect of explanatory variables associated with each fire event, on the posterior probability of the component that the fire belongs to, through a Dirichlet model. In an analysis of fire outcomes from British Columbia, Canada, we find that the majority of the fires are of normal or extreme magnitude in both outcomes, with strong evidence indicating correlation between duration and size. The effect of fire center, month, and several environmental covariates are identified as key predictors and we are able to determine through these approaches how these covariates differentially affect the four subpopulations.
A discontinuous Nitsche‐based finite element formulation for the imposition of the Navier‐slip condition over embedded volumeless geometries
Authors: Zorrilla Rubén , Larese de Tetto Antonia , Rossi Riccardo 
Published: June 2021

AbstractThis work describes a novel formulation for the simulation of incompressible Navier–Stokes problems involving nonconforming discretizations of membrane‐like bodies. The new proposal relies on the use of a modified finite element space within the elements intersected by the embedded geometry, which is represented by a discontinuous (or element‐by‐element) level set function. This is combined with a Nitsche‐based imposition of the general Navier‐slip boundary condition, to be intended as a wall law model. Thanks to the use of an alternative finite element space, the formulation is capable of reproducing exactly discontinuities across the embedded interface, while preserving the structure of the graph of the discrete matrix. The performance, accuracy and convergence of the new proposal is compared with analytical solutions as well as with a body fitted reference technique. Moreover, the proposal is tested against another similar embedded approach. Finally, a realistic application showcasing the possibilities of the method is also presented.
Effect of oven and sun drying on the chemical properties, lipid profile of soursop (Annona muricata) seed oil, and the functional properties of the defatted flour
Authors: Tiencheu Bernard , Claudia Egbe Agbor , Achidi Aduni Ufuan , Ngongang Eurydice Flore Tiepma , Tenyang Noel , Tonfack Djikeng Fabrice , Tatsinkou Fossi Bertrand 
Published: June 2021

AbstractSoursop seeds present a potential source of edible oil production. This work was aimed at determining the effect of oven and sun drying on the chemical properties and lipid profile of soursop seed oil as well as the functional properties of the defatted seed flour. The chemical properties, lipid profiles, and functional properties of soursop seeds dried for 0, 6, 12, 18, 24, and 30 hr, and 0, 1, 3, and 5 days, respectively, in the oven and on the sun using time T0 as the control sample were determined using oil quality indices, gas phase chromatography, and functionality tests for flours, respectively, with a view of highlighting the potentials of the defatted seed. The result of the study revealed that the chemical properties of oils for oven‐dried and sun‐dried seeds changed with drying technique and time, with iodine value being the more affected parameter, and peroxide value (PV) being the least. The control exhibited the highest free fatty acids (FFAs), peroxide value (PV), thiobarbituric acid (TBA) value, and saponification value compared with dried samples. The fatty acid profiling showed that the predominant fatty acids were C18:1n‐9, C18:2n‐6, and C16:0 and that unsaturated fatty acids (UFA), monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), and omega‐fats were not significantly affected by the oven drying time. The mean PUFA content ranged from 31.72% with sundried seeds to 30.92% after 30 hr of oven‐drying and was not significantly affected by the drying technique. The oils contained more n‐6 (30.60%) fatty acids than n‐3 (1.12%). The PUFA/SFA ratios [1.14–1.37] as well as the Atherogenic index (AI) [0.25–0.27] were acceptable because of the recommended range of FAO/WHO. PUFA/SFA, n‐6/n‐3, and Atherogenic index (AI) did not change much with the sun‐drying technique compared with oven‐drying. Flours from sun‐dried seeds had better functional properties than oven‐dried and more than 3 different types of proteins (based on isoelectric points of proteins). It can be concluded that soursop seed contains good quality oil, which can be exploited to improve nutrition. Manufacturers of animal feeds should explore the agro‐industrial use of its oil and defatted seed flour.
EEG and fMRI evidence for autobiographical memory reactivation in empathy
Authors: Meconi Federica , Linde‐Domingo Juan , S. Ferreira Catarina , Michelmann Sebastian , Staresina Bernhard , Apperly Ian A. , Hanslmayr Simon 
Published: June 2021

AbstractEmpathy relies on the ability to mirror and to explicitly infer others' inner states. Theoretical accounts suggest that memories play a role in empathy, but direct evidence of reactivation of autobiographical memories (AM) in empathy is yet to be shown. We addressed this question in two experiments. In Experiment 1, electrophysiological activity (EEG) was recorded from 28 participants. Participants performed an empathy task in which targets for empathy were depicted in contexts for which participants either did or did not have an AM, followed by a task that explicitly required memory retrieval of the AM and non‐AM contexts. The retrieval task was implemented to extract the neural fingerprints of AM and non‐AM contexts, which were then used to probe data from the empathy task. An EEG pattern classifier was trained and tested across tasks and showed evidence for AM reactivation when participants were preparing their judgement in the empathy task. Participants self‐reported higher empathy for people depicted in situations they had experienced themselves as compared to situations they had not experienced. A second independent fMRI experiment replicated this behavioural finding and showed increased activation for AM compared to non‐AM in the brain networks underlying empathy: precuneus, posterior parietal cortex, superior and inferior parietal lobule, and superior frontal gyrus. Together, our study reports behavioural, electrophysiological, and fMRI evidence that robustly supports AM reactivation in empathy.
Ketamine for Refractory Chronic Migraine: An Observational Pilot Study and Metabolite Analysis
Authors: Schwenk Eric S. , Torjman Marc C. , Moaddel Ruin , Lovett Jacqueline , Katz Daniel , Denk William , Lauritsen Clinton , Silberstein Stephen D. , Wainer Irving W. 
Published: June 2021

AbstractPatients with refractory chronic migraine have substantial disability and have failed many acute and preventive medications. When aggressive intravenous therapy is indicated, both lidocaine and (R,S)‐ketamine infusions have been used successfully to provide relief. Retrospective studies have shown that both agents may be associated with short‐term analgesia. In this prospective, observational pilot study of 6 patients, we compared the effects of lidocaine and (R,S)‐ketamine infusions and performed metabolite analyses of (R,S)‐ketamine to determine its metabolic profile in this population. One of (R,S)‐ketamine's metabolites, (2R,6R)‐hydroxynorketamine, has been shown in animal studies to reduce pain, but human studies in patients undergoing continuous (R,S)‐ketamine infusions for migraine are lacking. All 6 patients tolerated both infusions well with mild adverse effects. The baseline mean pain rating (0‐10 numeric rating scale) decreased from 7.5 ± 2.2 to 4.7 ± 2.8 by end of lidocaine treatment () but increased to 7.0 ± 1.4 by the postdischarge visit at 4 weeks (P > .05 vs baseline). The baseline mean pain rating prior to ketamine treatment was 7.4 ± 1.4, which decreased to 3.7 ± 2.3 by the end of the hospitalization () but increased to 7.2 ± 1.7 by the postdischarge visit at 6 weeks (P > .05 vs baseline). For the primary outcome the change in pain from baseline to end of treatment was greater for ketamine than lidocaine (–3.7 vs –2.8; ), but this has minimal clinical significance. Ketamine metabolite analysis revealed that (2R,6R)‐hydroxynorketamine was the predominant metabolite during most of the infusion, consistent with previous studies.
Hepatic Steatosis Has No Effect in Diagnosis Accuracy of LI‐RADS v2018 Categorization of Hepatocellular Carcinoma in MR Imaging
Authors: Yao Shan , Wei Yi , Ye Zheng , Chen Jie , Duan Ting , Zhang Zhen , Song Bin 
Published: June 2021

BackgroundIn clinical practice, hepatocellular carcinoma (HCC) is widely diagnosed by using MRI, however, whether the imaging features are affected by hepatic steatosis (HS) is still unknown.PurposeTo investigate and compare the differences in HCC related imaging features between with‐ and without‐HS groups, and to further determine whether HS affects the diagnosis accuracy of Liver Imaging Reporting and Data System (LI‐RADS) v2018 of HCC in MRI.Study TypeProspective.SubjectsOne hundred and seventy‐one patients (mean age, 52 ± 11 years; range, 26–83 years) including 137 men and 34 women.Field Strength/Sequence3.0 T, gradient echo (GRE).AssessmentSubjects were classified as HS and non‐HS groups according to MRI‐proton density fat‐fraction (PDFF). HS was defined as MRI‐PDFF >5.6%. Three radiologists accessed HCC features and assigned LI‐RADS categories in MRI independently based on LI‐RADS v2018. Frequencies of HCC major features and LR categorization assignment between the two groups as well as interobserver agreement between the two radiologists were assessed.Statistical TestsUnpaired t‐test, Chi‐square test, Fisher's exact test, kappa statistic, intraclass correlation coefficient (ICC). A two‐sided P value <0.05 was considered as statistically significant.ResultsMajor features including arterial hyperenhancement (APHE), enhancing “capsule” and nonperipheral “washout” observed between HS and non‐HS groups were not significantly different (78.95% vs.78.62%, P = 0.866; 57.89% vs.52.98%, P = 0.483; and 75% vs.81.46%, P = 0.257, respectively), and the assessment of observation size showed a borderline difference (P = 0.059). No significant difference in LR‐5 assignment between the two groups (69.74% vs. 72.85% for reader 1, P = 0.641; 71.05% vs. 72.19% for reader 2, P = 0.877). Interobserver agreement between the two radiologists showed almost perfect in LR‐5 assignment (κ = 0.869) and size observation (ICC = 0.997).Data ConclusionThe diagnosis of HCC based on LI‐RADS v2018 in MRI is of comparable performance regardless of HS, in which there is no significant difference in either the major imaging features or LR categorization.Level of Evidence: 2Technical Efficacy Stage: 2
COVID‐19 induced bradyarrhythmia and relative bradycardia: An overview
Authors: Douedi Steven , Mararenko Anton , Alshami Abbas , Al‐Azzawi Mohammed , Ajam Firas , Patel Swapnil , Douedi Hani , Calderon Dawn 
Published: June 2021

AbstractNovel coronavirus 2019 (COVID‐19) has been the focus of the medical community since its emergence in December 2019 and has already infected more than 100 million patients globally. Primarily described to cause a respiratory illness, COVID‐19 has been found to affect almost every organ system. Bradycardia is a newly recognized ramification of COVID‐19 that still has unknown prognostic value. Studies have shown an increase in the incidence of arrhythmias, cardiomyopathies, myocarditis, acute coronary syndromes, and coagulopathies in infected patients as well as an increased risk of mortality in patients with preexisting cardiovascular disease. While the pathogenesis of bradycardia in COVID‐19 may be multifactorial, clinicians should be aware of the mechanism by which COVID‐19 affects the cardiovascular system and the medication side effects which are used in the treatment algorithm of this deadly virus. There has yet to be a comprehensive review analyzing bradyarrhythmia and relative bradycardia in COVID‐19 infected patients. We aim to provide a literature review including the epidemiology, pathogenesis, and management of COVID‐19 induced bradyarrhythmia.
Peritraumatic Distress and Posttraumatic Stress Symptoms During the COVID‐19 Pandemic: The Contributions of Psychosocial Factors and Pandemic‐Related Stressors
Authors: Antičević Vesna , Bubić Andreja , Britvić Dolores 
Published: June 2021

AbstractThe present study aimed to identify the contributions of sociodemographic factors, psychological hardiness, and pandemic‐related stressors to the development of peritraumatic distress and posttraumatic stress symptoms (PTSS) during the peak of the COVID‐19 pandemic. We also examined the mediating contribution of peritraumatic distress with respect to the associations between PTSS and (a) individual characteristics and (b) pandemic‐related stressors. A total of 1,238 participants (82.1% women, 17.9% men) aged 18–75 years were included in the study. Participants completed the Dispositional Resilience Scale, Peritraumatic Distress Inventory, and Posttraumatic Stress Disorder (PTSD) Checklist. The results showed that 11.5% of participants scored above the clinical cutoff for peritraumatic distress, and 12.8% of participants scored above the clinical cutoff for PTSS. Regression models showed that higher levels of peritraumatic distress were statistically predicted by female gender, β = ‐.12, p < .001; exposure to more than one stressor, β = .21, p < .001; lower levels of commitment to people and activities, β = –.12, p = .002; and resistance to challenges, β = –.17, p < .001. Additionally, male gender, β = .05, p = .007; younger age, β = –.05, p = .005; lower levels of commitment to people and activities, β = –.11, p < .001; lower ratings of hardiness with regard to challenge, β = –.04, p = .043; and more severe peritraumatic distress, β = .75, p < .001, predicted more severe PTSS during the pandemic. Peritraumatic distress mediated the associations between PTSS and both the number of experienced stressors and psychological hardiness.