bluuebunny/crossref_metadata_2025_split huggingface dataset:
A novel approach for discovering stochastic models behind data applied to El Niño–Southern Oscillation
Authors: Olson Roman , An Soon-Il , Kim Soong-Ki , Fan Yanan 
Published: January 2021

AbstractStochastic differential equations (SDEs) are ubiquitous across disciplines, and uncovering SDEs driving observed time series data is a key scientific challenge. Most previous work on this topic has relied on restrictive assumptions, undermining the generality of these approaches. We present a novel technique to uncover driving probabilistic models that is based on kernel density estimation. The approach relies on few assumptions, does not restrict underlying functional forms, and can be used even on non-Markov systems. When applied to El Niño–Southern Oscillation (ENSO), the fitted empirical model simulations can almost perfectly capture key time series properties of ENSO. This confirms that ENSO could be represented as a two-variable stochastic dynamical system. Our experiments provide insights into ENSO dynamics and suggest that state-dependent noise does not play a major role in ENSO skewness. Our method is general and can be used across disciplines for inverse and forward modeling, to shed light on structure of system dynamics and noise, to evaluate system predictability, and to generate synthetic datasets with realistic properties.
Reconstructing population dynamics of a threatened marine mammal using multiple data sets
Authors: Hostetler Jeffrey A. , Martin Julien , Kosempa Michael , Edwards Holly H. , Rood Kari A. , Barton Sheri L. , Runge Michael C. 
Published: January 2021

AbstractModels of marine mammal population dynamics have been used extensively to predict abundance. A less common application of these models is to reconstruct historical population dynamics, filling in gaps in observation data by integrating information from multiple sources. We developed an integrated population model for the Florida manatee (Trichechus manatus latirostris) to reconstruct its population dynamics in the southwest region of the state over the past 20 years. Our model improved precision of key parameter estimates and permitted inference on poorly known parameters. Population growth was slow (averaging 1.02; 95% credible interval 1.01–1.03) but not steady, and an unusual mortality event in 2013 led to an estimated net loss of 332 (217–466) manatees. Our analyses showed that precise estimates of abundance could be derived from estimates of vital rates and a few input estimates of abundance, which may mean costly surveys to estimate abundance don’t need to be conducted as frequently. Our study also shows that retrospective analyses can be useful to: (1) model the transient dynamics of age distribution; (2) assess and communicate the conservation status of wild populations; and (3) improve our understanding of environmental effects on population dynamics and thus enhance our ability to forecast.
Intra-bundle contractions enable extensile properties of active actin networks
Authors: Bleicher P. , Nast-Kolb T. , Sciortino A. , de la Trobe Y. A. , Pokrant T. , Faix J. , Bausch A. R. 
Published: January 2021

AbstractThe cellular cortex is a dynamic and contractile actomyosin network modulated by actin-binding proteins. We reconstituted a minimal cortex adhered to a model cell membrane mimicking two processes mediated by the motor protein myosin: contractility and high turnover of actin monomers. Myosin reorganized these networks by extensile intra‑bundle contractions leading to an altered growth mechanism. Hereby, stress within tethered bundles induced nicking of filaments followed by repair via incorporation of free monomers. This mechanism was able to break the symmetry of the previously disordered network resulting in the generation of extensile clusters, reminiscent of structures found within cells.
Chimeric synthetic reference standards enable cross-validation of positive and negative controls in SARS-CoV-2 molecular tests
Authors: Madala Bindu Swapna , Reis Andre L. M. , Deveson Ira W. , Rawlinson William , Mercer Tim R. 
Published: January 2021

AbstractDNA synthesis in vitro has enabled the rapid production of reference standards. These are used as controls, and allow measurement and improvement of the accuracy and quality of diagnostic tests. Current reference standards typically represent target genetic material, and act only as positive controls to assess test sensitivity. However, negative controls are also required to evaluate test specificity. Using a pair of chimeric A/B RNA standards, this allowed incorporation of positive and negative controls into diagnostic testing for the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). The chimeric standards constituted target regions for RT-PCR primer/probe sets that are joined in tandem across two separate synthetic molecules. Accordingly, a target region that is present in standard A provides a positive control, whilst being absent in standard B, thereby providing a negative control. This design enables cross-validation of positive and negative controls between the paired standards in the same reaction, with identical conditions. This enables control and test failures to be distinguished, increasing confidence in the accuracy of results. The chimeric A/B standards were assessed using the US Centres for Disease Control real-time RT-PCR protocol, and showed results congruent with other commercial controls in detecting SARS-CoV-2 in patient samples. This chimeric reference standard design approach offers extensive flexibility, allowing representation of diverse genetic features and distantly related sequences, even from different organisms.
Saccadic reaction time in mirror image sectors across horizontal meridian in eye movement perimetry
Authors: Mazumdar Deepmala , Meethal Najiya S. Kadavath , George Ronnie , Pel Johan J. M. 
Published: January 2021

AbstractIn eye movement perimetry (EMP), the saccadic reaction time (SRT) to ‘seen’ visual stimuli are delayed in glaucoma. Evaluating SRT behaviour in hemi-field sectors could refine its clinical implication. The development phase included 60 controls retrospectively and for the test cohort in evaluation phase, another 30 healthy subjects and 30 glaucoma patients were recruited prospectively. The SRTs were used to calculate the normative limits within 5 predefined hemi-field sectors. Scores were assigned to probabilities for SRT at the level of 5%, 2.5% 1% and 0.5%. Per sector pair, a probability score limit (PSL) was calculated at each of the four levels and were compared with the scores obtained from the test cohort. The classification accuracy ‘normal versus abnormal’ was assessed for PSL in EMP and compared with glaucoma hemi-field test in standard automated perimetry. We found no statistically significant differences in SRTs between the mirror sectors in healthy subjects. The PSL at 2.5% had moderate classification accuracy with a specificity of 77% and sensitivity 70%. This could be suggestive of an SRT delay in the overall visual field in glaucoma.
Transmission dynamics and control measures of COVID-19 outbreak in China: a modelling study
Authors: Zhang Xu-Sheng , Vynnycky Emilia , Charlett Andre , De Angelis Daniela , Chen Zhengji , Liu Wei 
Published: January 2021

AbstractCOVID-19 is reported to have been brought under control in China. To understand the COVID-19 outbreak in China and provide potential lessons for other parts of the world, in this study we apply a mathematical model with multiple datasets to estimate the transmissibility of the SARS-CoV-2 virus and the severity of the illness associated with the infection, and how both were affected by unprecedented control measures. Our analyses show that before 19th January 2020, 3.5% (95% CI 1.7–8.3%) of infected people were detected; this percentage increased to 36.6% (95% CI 26.1–55.4%) thereafter. The basic reproduction number (R0) was 2.33 (95% CI 1.96–3.69) before 8th February 2020; then the effective reproduction number dropped to 0.04(95% CI 0.01–0.10). This estimation also indicates that control measures taken since 23rd January 2020 affected the transmissibility about 2 weeks after they were introduced. The confirmed case fatality rate is estimated at 9.6% (95% CI 8.1–11.4%) before 15 February 2020, and then it reduced to 0.7% (95% CI 0.4–1.0%). This shows that SARS-CoV-2 virus is highly transmissible but may be less severe than SARS-CoV-1 and MERS-CoV. We found that at the early stage, the majority ofR0comes from undetected infectious people. This implies that successful control in China was achieved through reducing the contact rates among people in the general population and increasing the rate of detection and quarantine of the infectious cases.
Study of mouse behavior in different gravity environments
Authors: Shimomura Michihiko , Yumoto Akane , Ota-Murakami Naoko , Kudo Takashi , Shirakawa Masaki , Takahashi Satoru , Morita Hironobu , Shiba Dai 
Published: January 2021

AbstractMany experiments have analyzed the effect of the space environment on various organisms. However, except for the group-rearing of mice in space, there has been little information on the behavior of organisms in response to gravity changes. In this study, we developed a simple Active Inactive Separation (AIS) method to extract activity and inactivity in videos obtained from the habitat cage unit of a space experiment. This method yields an activity ratio as a ratio of ‘activity’ within the whole. Adaptation to different gravitational conditions from 1gto hypergravity (HG) and from microgravity (MG) to artificial 1g(AG) was analyzed based on the amount of activity to calculate the activity ratio and the active interval. The result for the activity ratios for the ground control experiment using AIS were close to previous studies, so the effectiveness of this method was indicated. In the case of changes in gravity from 1gto HG, the ratio was low at the start of centrifugation, recovered sharply in the first week, and entered a stable period in another week. The trend in the AG and HG was the same; adapting to different gravity environments takes time.
Dexamethasone increased the survival rate in Plasmodium berghei-infected mice
Authors: Moreira Danilo Reymão , Uberti Ana Carolina Musa Gonçalves , Gomes Antonio Rafael Quadros , Ferreira Michelli Erica Souza , da Silva Barbosa Aline , Varela Everton Luiz Pompeu , Dolabela Maria Fani , Percário Sandro 
Published: January 2021

AbstractThe present study aimed to evaluate the effects of dexamethasone on the redox status, parasitemia evolution, and survival rate of Plasmodium berghei-infected mice. Two-hundred and twenty-five mice were infected with Plasmodium berghei and subjected to stimulation or inhibition of NO synthesis. The stimulation of NO synthesis was performed through the administration of L-arginine, while its inhibition was made by the administration of dexamethasone. Inducible NO synthase (iNOS) inhibition by dexamethasone promoted an increase in the survival rate of P. berghei-infected mice, and the data suggested the participation of oxidative stress in the brain as a result of plasmodial infection, as well as the inhibition of brain NO synthesis, which promoted the survival rate of almost 90% of the animals until the 15th day of infection, with possible direct interference of ischemia and reperfusion syndrome, as seen by increased levels of uric acid. Inhibition of brain iNOS by dexamethasone caused a decrease in parasitemia and increased the survival rate of infected animals, suggesting that NO synthesis may stimulate a series of compensatory redox effects that, if overstimulated, may be responsible for the onset of severe forms of malaria.
Experimental warming increases ecosystem respiration by increasing above-ground respiration in alpine meadows of Western Himalaya
Authors: Tiwari Pankaj , Bhattacharya Pamela , Rawat Gopal Singh , Rai Ishwari Datt , Talukdar Gautam 
Published: January 2021

AbstractAlpine ecosystems in the Himalaya, despite low primary productivity, store considerable amount of organic carbon. However, these ecosystems are highly vulnerable to climate warming which may stimulate ecosystem carbon efflux leading to carbon-loss and positive feedback. We used open-top chambers to understand warming responses of ecosystem respiration (ER) and soil respiration (SR) in two types of alpine meadows viz., herbaceous meadow (HM) and sedge meadow (SM), in the Western Himalaya. Experimental warming increased ER by 33% and 28% at HM and SM, respectively. No significant effect on SR was observed under warming, suggesting that the increase in ER was primarily due to an increase in above-ground respiration. This was supported by the warming-induced increase in above-ground biomass and decrease in SR/ER ratio. Soil temperature was the dominant controlling factor of respiration rates and temperature sensitivity of both ER and SR increased under warming, indicating an increase in contribution from plant respiration. The findings of the study suggest that climate warming by 1.5–2 °C would promote ER via increase in above-ground respiration during the growing season. Moreover, net C uptake in the alpine meadows may increase due to enhanced plant growth and relatively resistant SR under warming.
Biomechanical properties of a novel nonfusion artificial vertebral body for anterior lumbar vertebra resection and internal fixation
Authors: Liu Jiantao , He Xijing , Niu Binbin , Yang Yin , Gao Yanzheng , Xiu Jintao , Wang Hongbo , Wang Yanbiao 
Published: January 2021

AbstractThe aim of the study was to evaluate the biomechanical properties of a novel nonfused artificial vertebral body in treating lumbar diseases and to compare with those of the fusion artificial vertebral body. An intact finite element model of the L1–L5 lumbar spine was constructed and validated. Then, the finite element models of the fusion group and nonfusion group were constructed by replacing the L3 vertebral body and adjacent intervertebral discs with prostheses. For all finite element models, an axial preload of 500 N and another 10 N m imposed on the superior surface of L1. The range of motion and stress peaks in the adjacent discs, endplates, and facet joints were compared among the three groups. The ranges of motion of the L1–2 and L4–5 discs in flexion, extension, left lateral bending, right lateral bending, left rotation and right rotation were greater in the fusion group than those in the intact group and nonfusion group. The fusion group induced the greatest stress peaks in the adjacent discs and adjacent facet joints compared to the intact group and nonfusion group. The nonfused artificial vertebral body could better retain mobility of the surgical site after implantation (3.6°–8.7°), avoid increased mobility and stress of the adjacent discs and facet joints.
Effects of sagging breasts and other risk factors associated with mastalgia: a case–control study
Authors: Çomçalı Bülent , Kocaoz Servet , Özdemir Buket Altun , Parlak Ömer , Korukluoğlu Birol 
Published: January 2021

AbstractThe aim of this study is to compare patients with and without mastalgia and to analyze the factors affecting mastalgia and its severity. The patient’s age, height, weight, educational status, marital status, and occupation were recorded in all subjects. In addition, the women were asked about the presence of any risk factors for mastalgia, such as tea and coffee consumption, smoking, alcohol consumption, and weight gain. The sternal notch to nipple distance (SNND) was measured to determine whether there was breast sagging. Mastalgia was significantly more common in women with BMIs of > 30 kg/m2 (OR: 2.94, CI 1.65–5.24), those who were primary school graduates or illiterate (OR: 2.96, CI 1.6–5.46), and those with SNND values of 22–25 cm (OR: 2.94, CI 1.79–4.82). In these women, drinking more than 6 cups of tea a day (OR: 2.15, CI 1.32–3.5), smoking at least 10 cigarettes a day (OR: 2.94, CI 1.78–4.83), and drinking alcohol at least once a week (OR: 2.1, CI 1.12–3.91) were found to be important factors that increased the risk of mastalgia. As a result, it has been found that severe mastalgia complaints cause by obesity, sagging breasts, never giving birth, unemployment anxiety, regular smoking, alcohol use, and excessive tea consumption.
Optimal location of water level sensors for monitoring mine water inrush based on the set covering model
Authors: Wu Qiang , Du Zhili , Zhao Yingwang , Xu Hua , Zhang Xiaoyan 
Published: January 2021

AbstractWater inrush is one of the major mining disasters that may lead to numerous casualties. The development of information techniques makes it possible to monitor the occurrence and evolution of water inrush. Then, locating monitors for water inrush becomes a primary problem. This study presents a method of optimal location of water level sensors by constructing a set covering model. The monitoring scope of the water level sensor at each location in a given time is computed first based on the numerical simulation of water spreading along mine tunnels. In this simulation, the water inrush quantity is assigned using the mine drainage capability over which an accident may occur. Then the greedy algorithm is used to optimize the number and positions of water level sensors. As results, a mine water disaster can be monitored in the given time after it happened. The proposed method is then verified in the Beiyangzhuang coal mine in the North China. The results show that at least 22, 36, 42, 64 and 106 water level sensors are needed to monitor water disasters in the whole mine within 60, 30, 20, 10 and 5 min, respectively.
The influence of distance weight on the inverse distance weighted method for ore-grade estimation
Authors: Liu Zhan-Ning , Yu Xiao-Yan , Jia Li-Feng , Wang Yuan-Sheng , Song Yu-Chen , Meng Hai-Dong 
Published: January 2021

AbstractIn order to study the influence of distance weight on ore-grade estimation, the inverse distance weighted (IDW) is used to estimate the Ni grade and MgO grade of serpentinite ore based on a three-dimensional ore body model and related block models. Manhattan distance, Euclidean distance, Chebyshev distance, and multiple forms of the Minkowski distance are used to calculate distance weight of IDW. Results show that using the Minkowski distance for the distance weight calculation is feasible. The law of the estimated results along with the distance weight is given. The study expands the distance weight calculation method in the IDW method, and a new method for improving estimation accuracy is given. Researchers can choose different weight calculation methods according to their needs. In this study, the estimated effect is best when the power of the Minkowski distance is 3 for a 10 m × 10 m × 10 m block model. For a 20 m × 20 m × 20 m block model, the estimated effect is best when the power of the Minkowski distance is 9.
Bilateral vestibulopathy causes selective deficits in recombining novel routes in real space
Authors: Schöberl Florian , Pradhan Cauchy , Grosch Maximilian , Brendel Matthias , Jostes Florian , Obermaier Katrin , Sowa Chantal , Jahn Klaus , Bartenstein Peter , Brandt Thomas , Dieterich Marianne , Zwergal Andreas 
Published: January 2021

AbstractThe differential impact of complete and incomplete bilateral vestibulopathy (BVP) on spatial orientation, visual exploration, and navigation-induced brain network activations is still under debate. In this study, 14 BVP patients (6 complete, 8 incomplete) and 14 age-matched healthy controls performed a navigation task requiring them to retrace familiar routes and recombine novel routes to find five items in real space. [18F]-fluorodeoxyglucose-PET was used to determine navigation-induced brain activations. Participants wore a gaze-controlled, head-fixed camera that recorded their visual exploration behaviour. Patients performed worse, when recombining novel routes (p < 0.001), whereas retracing of familiar routes was normal (p = 0.82). These deficits correlated with the severity of BVP. Patients exhibited higher gait fluctuations, spent less time at crossroads, and used a possible shortcut less often (p < 0.05). The right hippocampus and entorhinal cortex were less active and the bilateral parahippocampal place area more active during navigation in patients. Complete BVP showed reduced activations in the pontine brainstem, anterior thalamus, posterior insular, and retrosplenial cortex compared to incomplete BVP. The navigation-induced brain activation pattern in BVP is compatible with deficits in creating a mental representation of a novel environment. Residual vestibular function allows recruitment of brain areas involved in head direction signalling to support navigation.
Optimisation of virtual cooperative spectrum sensing for UAV‐based interweave cognitive radio system
Authors: Wu Jun , Chen Yang , Li Pei , Zhang Jia , Wang Cong , Tang Jifei , Xia Lanhua , Lu Conghui , Song Tiecheng 
Published: January 2021

AbstractIn an interweave cognitive radio system, cooperative spectrum sensing has been recognised as a key technology to enable secondary users to opportunistically access licensed spectrum band without harmful interference to primary users. At the same time, the unmanned aerial vehicle equipped with spectrum sensing and data transmission facilities is gaining more popularity in different applications. An unmanned aerial vehicle‐based interweave cognitive radio is investigated in which the unmanned aerial vehicle is used as a secondary user, but unlike the participation of multiple secondary users in traditional cooperative spectrum sensing, a virtual cooperative spectrum sensing model is introduced into the periodic spectrum sensing frame structure. Afterwards, the authors further propose an energy‐efficient virtual cooperative spectrum sensing with the sequential 0/1 fusion rule to reduce the average number of decisions without any loss in the detection performance. Sequentially, the authors formulate the optimisation of virtual cooperative spectrum sensing for unmanned aerial vehicle‐based interweave cognitive ratio system as the optimal sequential 0/1 fusion problem on the basis of the K‐out‐of‐N fusion rule and prove the formulated problem indeed has one optimal K, which yields the highest throughput. Finally, numerical simulations are presented to demonstrate the correctness of theoretical analyses and the effectiveness of the virtual cooperative spectrum sensing with the sequential 0/1 fusion rule.
A specific perspective: Subway driver behaviour recognition using CNN and time‐series diagram
Authors: Huang Shize , Yang Lingyu , Chen Wei , Tao Ting , Zhang Bingjie 
Published: January 2021

AbstractUrban rail transit, especially the subway, has been booming in China for a decade, imposing safety challenges on all related parties. Drivers’ behaviours are particularly crucial. Typically, drivers’ actions are recorded by cameras, and the surveillance videos are evaluated manually. Current driver behaviour recognition methods mostly target the bus or car drivers and can hardly be implemented for subways, because subway drivers follow a rigid working code that needs a time sequence of movements to describe. In this study, we propose a recognition model to automatically recognise behaviours from single‐frame images that are extracted from surveillance videos; second, we convert the recognition results into time series diagrams, thus the recognised behaviours can be interpreted and analysed statistically and effectively. The validation experiments demonstrate that the convolutional neural network model can recognise 96.20% driver behaviours, and time series diagrams add time information to the behaviours, providing a convincible reference for subway driver evaluation.