bluuebunny/crossref_metadata_2025 huggingface dataset:
Heat shock during in vitro maturation of bovine oocytes disturbs bta‐miR‐19b and DROSHA transcripts abundance after in vitro fertilization
Authors: Souza Vanessa das Graças Pereira de , Souza Gustavo Torres de , Lemos Diana Rangel de , Guimarães Judith Maria de Oliveira , Quintão Carolina Capobiango Romano , Munk Michele , Saraiva Naiara Zoccal , Camargo Luiz Sérgio de Almeida
Published: May 2021

While microRNAs (miRNAs) are a class of non‐coding RNAs important for embryo development, the relationship between them and heat stress during oocyte maturation has not yet been established. This study investigated the effect of heat shock during in vitro maturation (IVM) on the abundance of bta‐miR‐20a, −27b, −103, −21‐5p, −19b, −1246 miRNAs and DROSHA and DICER1 mRNAs, previously reported for being involved in oocyte maturation, response to heat stress and miRNA biogenesis. Oocytes were exposed for 12h to heat shock during IVM, fertilized in vitro and the presumptive zygotes cultured for eight days. The relative quantification of miRNAs and mRNAs was performed by real‐time PCR in vitro‐matured oocytes and 8‐cell stage embryos. Progression of meiosis, embryonic development and apoptotic indices was also evaluated. Heat shock compromised (p < .05) oocyte nuclear maturation, cleavage and embryo development, with a higher (p < .05) embryonic apoptotic index than the control group. The abundance of bta‐miR‐19b increased (p < .05) whereas the abundance of DROSHA transcripts decreased (p < .05) in embryos derived from heat‐shocked oocytes. In conclusion, heat shock during IVM influences the abundance of bta‐miR‐19b and DROSHA in pre‐implantation embryos, indicating a persistent effect of heat shock that can be associated with impaired embryo development.
G protein‐coupled estrogen receptor 1 inhibits the epithelial–mesenchymal transition of goat mammary epithelial cells via NF‐κB signalling pathway
Authors: Zhao Ying , Yang Zhenshan , Miao Yuyang , Fan Mingzhen , Zhao Xiaoe , Wei Qiang , Ma Baohua
Published: May 2021

Mastitis is one of the most frequent clinical diseases in dairy animals. Epithelial cells undergoing epithelial–mesenchymal transition (EMT) promote the process of mastitis. Oestrogen deficiency is disadvantaged of many tissue inflammation and regeneration, while exogenous oestrogen treatment can reverse these effects. G protein‐coupled estrogen receptor 1 (GPER1) is a membrane estrogen receptor. However, the potential effects of oestrogen via GPER1 on EMT in goat mammary epithelial cells (GMECs) are still unclear. Here, this study discovered that the activation of GPER1 by oestrogen could inhibit the EMT in GMECs via NF‐κB signalling pathway. The activation of GPER1 by oestrogen inhibited the EMT accompanied by upregulation of E‐cadherin and downregulation of N‐cadherin and vimentin. Meanwhile, mRNA expression of transcription factors including Snail1 and ZEB1 was decreased. Further, like to oestrogen, GPER1 agonist G1 repressed the EMT progression. Conversely, GPER1 antagonist G15 reversed all these features induced by oestrogen. What's more, GPER1 silencing with shRNA promoted GMECs undergoing EMT. Additionally, oestrogen increased the phosphorylation of Erk1/2, which then decreased the phosphorylation and nuclear translocation of NF‐κB, inhibiting the NF‐κB signalling pathway activity. Taken, GPER1 may act as a suppressor through the regulation of EMT to prevent the development of mastitis.
True substrates: The exceptional resolution and unexceptional preservation of deep time snapshots on bedding surfaces
Authors: Davies Neil S. , Shillito Anthony P.
Published: May 2021

Rock outcrops of the sedimentary–stratigraphic record often reveal bedding planes that can be considered to be true substrates: preserved surfaces that demonstrably existed at the sediment–water or sediment–air interface at the time of deposition. These surfaces have high value as repositories of palaeoenvironmental information, revealing fossilized snapshots of microscale topography from deep time. Some true substrates are notable for their sedimentary, palaeontological and ichnological signatures that provide windows into key intervals of Earth history, but countless others occur routinely throughout the sedimentary–stratigraphic record. They frequently reveal patterns that are strikingly familiar from modern sedimentary environments, such as ripple marks, animal trackways, raindrop impressions or mudcracks: all phenomena that are apparently ephemeral in modern settings, and which form on recognizably human timescales. This paper sets out to explain why these short‐term, transient, small‐scale features are counter‐intuitively abundant within a 3.8 billion year‐long sedimentary–stratigraphic record that is known to be inherently time‐incomplete. True substrates are fundamentally related to a state of stasis in ancient sedimentation systems, and distinguishable from other types of bedding surfaces that formed from a dominance of states of deposition or erosion. Stasis is shown to play a key role in both their formation and preservation, rendering them faithful and valuable archives of palaeoenvironmental and temporal information. Further, the intersection between the time–length scale of their formative processes and outcrop expressions can be used to explain why they are so frequently encountered in outcrop investigations. Explaining true substrates as inevitable and unexceptional by‐products of the accrual of the sedimentary–stratigraphic record should shift perspectives on what can be understood about Earth history from field studies of the sedimentary–stratigraphic record. They should be recognized as providing high‐definition information about the mundane day to day operation of ancient environments, and critically assuage the argument that the incomplete sedimentary–stratigraphic record is unrepresentative of the geological past.
Circulating microRNAs after a 24‐h ultramarathon run in relation to muscle damage markers in elite athletes
Authors: Chalchat Emeric , Charlot Keyne , Garcia‐Vicencio Sebastian , Hertert Pierre , Baugé Stéphane , Bourdon Stéphanie , Bompard Julie , Farges Cédric , Martin Vincent , Bourrilhon Cyprien , Siracusa Julien
Published: May 2021

Ultra‐endurance sports are growing in popularity but can be associated with adverse health effects, such as exercise‐induced muscle damage (EIMD), which can lead to exertional rhabdomyolysis. Circulating microRNAs (miRNAs) may be useful to approach the degree of EIMD. We aimed to (1) investigate the relevance of circulating miRNAs as biomarkers of muscle damage and (2) examine the acute response of skeletal/cardiac muscle and kidney biomarkers to a 24‐h run in elite athletes. Eleven elite athletes participated in the 24‐h run World Championships. Counter‐movement jump (CMJ), creatine kinase (CK), myoglobin (Mb), creatinine (Cr), high‐sensitive cardiac troponin T (hs‐cTnT), and muscle‐specific miRNA (myomiR) levels were measured before, immediately after, and 24 and 48h after the race. CMJ height was reduced immediately after the race (−84.0 ± 25.2%, p < 0.001) and remained low at 24 h (−43.6 ± 20.4%, p = 0.002). We observed high CK activity (53 239 ± 63 608 U/L, p < 0.001) immediately after the race, and it remained elevated 24h after (p < 0.01). Circulating myomiR levels (miR‐1‐3p, miR‐133a‐3p, miR‐133b, miR‐208a‐3p, miR‐208b‐3p, and miR‐499a‐5p) were elevated immediately after the 24‐h run (fold changes: 18–124,723, p<0.001) and significantly (p < 0.05) correlated or tended to significantly (p < 0.07) correlate with the reduction in CMJ height at 24 h. We found no significant correlation between CMJ height loss at 24 h and CK (p = 0.23) or Mb (p = 0.41) values. All elite ultramarathon runners included in our study were diagnosed with exertional rhabdomyolysis after the 24‐h ultramarathon race. MyomiR levels may be useful to approach the degree of muscle damage.
Going against the grain: Unravelling the habitus of older farmers to help facilitate generational renewal in agriculture
Authors: Conway Shane Francis , McDonagh John , Farrell Maura , Kinsella Anne
Published: May 2021

Limited uptake of financial incentives, designed to confront global trends of an ageing farming population and low levels of land mobility, reveal resistance or at best ambivalence, amongst farmers towards altering existing farm management and ownership structures in later life. To uncover facets governing the mindset, disposition and practices of older farmers towards succession and retirement, this study draws on Bourdieu's notion of habitus. A multi‐method triangulation methodology is employed to obtain in‐depth understandings of the senior generation's deeply embedded views, and the changes they perceive will occur upon their engagement in the process. Findings reveal that the attitudes and behaviour required to ‘step aside’ and retire from farming not only ‘go against the grain’ of the older farmers’ habitus, appearing to be instinctively ‘wrong’, they also appear incompatible with what is necessary to earn recognition as a ‘good farmer’. The article concludes by recommending that a shift in thinking towards succession and retirement must be confronted at an earlier life stage in order to inculcate a new farming habitus. In doing this, long‐term resolutions through generating a regularised, accepted and well‐regarded practice of intergenerational farm transfer within the farming community would be promoted.
Reconstructing craton‐scale tectonic events via in situ Rb‐Sr geochronology of poly‐phased vein mineralization
Authors: Tillberg Mikael , Drake Henrik , Zack Thomas , Hogmalm Johan , Kooijman Ellen , Åström Mats
Published: May 2021

Fault‐ and fracture‐hosted multi‐stage mineral assemblages that formed by fracture reactivation and fluid migration, constitute archives of the tectonic evolution of Precambrian cratons. Complex intergrowth patterns of these mineral records often hinder absolute dating of mineralization events for geological models. We apply LA‐ICP‐MS/MS in situ Rb‐Sr dating of single crystal growth zones in sub‐mm‐wide vein mineralization assemblages including illite, K‐feldspar, albite, calcite, mica, zeolites, fluorite and/or epidote at three Palaeoproterozoic crystalline bedrock sites over 300 km apart in the Fennoscandian Shield. The dating campaign reveals multiple age clusters between ca. 1757 ± 15 and 355 ± 12 Ma correlating with fluid flow and fracture reactivation events initiated by far‐field orogens and their foreland basin evolution. This new approach for reconstructing geological histories of Precambrian cratons connects micro‐scale age determinations of different mineral growth zones in fractures with regional‐scale crustal dynamic responses to tectonic events.
A eulogy for Dr Francisco Miguel Marty Forero
Authors: Koo Sophia , Bold Tyler D. , Cheng Matthew Pellan , Farmakiotis Dimitrios , Hill Joshua A. , Knoll Bettina , Koullias Yiannis , Letourneau Alyssa R. , Little Jessica , Moulton Elizabeth A. , Weiss Zoe Freeman , Hammond Sarah P.
Published: May 2021

As some of those who were lucky enough to have been mentored by Dr Francisco Marty in transplant infectious diseases, we stand with the larger medical community in mourning his untimely death and in commemorating him as a uniquely exceptional and talented physician, investigator, teacher, mentor, friend, artist, and human being.
MeRAV5 promotes drought stress resistance in cassava by modulating hydrogen peroxide and lignin accumulation
Authors: Yan Yu , Wang Peng , Lu Yi , Bai Yujing , Wei Yunxie , Liu Guoyin , Shi Haitao
Published: May 2021

Cassava, an important food and energy crop, is relatively more resistant to drought stress than other crops. However, the molecular mechanism underlying this resistance remains elusive. Herein, we report that silencing a drought stress‐responsive transcription factor MeRAV5 significantly reduced drought stress resistance, with higher levels of hydrogen peroxide (H2O2) and less lignin during drought stress. Yeast two‐hybrid, pull down and bimolecular fluorescence complementation (BiFC) showed that MeRAV5 physically interacted with peroxidase (MePOD) and lignin‐related cinnamyl alcohol dehydrogenase 15 (MeCAD15) in vitro and in vivo. MeRAV5 promoted the activities of both MePOD and MeCAD15 to affect H2O2 and endogenous lignin accumulation respectively, which are important in drought stress resistance in cassava. When either MeCAD15 or MeRAV5 was silenced, or both were co‐silenced, cassava showed lower lignin content and drought‐sensitive phenotype, whereas exogenous lignin alkali treatment increased drought stress resistance and alleviated the drought‐sensitive phenotype of these silenced cassava plants. This study documents that the modulation of H2O2 and lignin by MeRAV5 is essential for drought stress resistance in cassava.
Characterizing the molecular and immune landscape of canine bladder cancer
Authors: Cronise Kathryn E. , Das Sunetra , Hernandez Belen G. , Regan Daniel P. , Dailey Deanna D. , McGeachan Robert I. , Lana Susan E. , Page Rodney L. , Gustafson Daniel L. , Duval Dawn L.
Published: May 2021

Transitional cell carcinoma (TCC), also known as urothelial carcinoma, is the most common bladder cancer in humans and dogs. Approximately one‐quarter of human TCCs are muscle‐invasive and associated with a high risk of death from metastasis. Canine TCC (cTCC) tumours are typically high‐grade and muscle‐invasive. Shared similarities in risk factors, histopathology, and clinical presentation suggest that cTCC may serve as a model for the assessment of novel therapeutics that may inform therapies for human muscle‐invasive TCC. The goal of this study was to characterize cTCC at the molecular level to identify drivers of oncogenesis and druggable targets. We performed whole exome sequencing (WES) of 11 cTCC tumours and three matched normal samples, identifying 583 variants in protein‐coding genes. The most common variant was a V‐to‐E missense mutation in BRAF, identified in 4 out of 11 samples (36%) via WES. Sanger sequencing identified BRAF variants in 8 out of the same 11 cTCC samples, as well as in 22 out of 32 formalin‐fixed paraffin embedded (FFPE) cTCC samples, suggesting an overall prevalence of 70%. RNA‐Seq was performed to compare the gene expression profiles of cTCC tumours to normal bladder tissue. cTCC tumours exhibited up‐regulation of genes involved in the cell cycle, DNA repair, and antiviral immunity. We also analysed the immune landscape of cTCC using immune gene signatures and immunohistochemical analysis. A subset of tumours had characteristics of a hot tumour microenvironment and exhibited high expression of signatures associated with complete response to PD‐1/PD‐L1 blockade in human bladder cancer.
Serial-robot Wrist-singularity Mitigation Along Alternative Optimally Adjusted Paths
Authors: Milenkovic Paul H.
Published: May 2021

Adjusting the displacement path of a serial robot encountering the wrist singularity to pass either through the singularity or around it mitigates its adverse effects. Both such path adjustments are commonly called singularity avoidance and are applied here to either a spherical or an offset wrist. These adjustments avoid high joint rates that can occur at singularity encounter. A recent through-the singularity method limits joint rates and accelerations in the robot with either a spherical or offset wrist when conducting a constant rate of traversal of the tool manipulated by the robot. A kinematic model adding multiple virtual joints allows a modified high-order path-following algorithm to maintain accurate tool position while achieving an optimal level of tool deviation in orientation. Whereas a path reversal resulting from a turning-point type singularity had been revealed for an offset wrist over a finite range of close-approach, these conditions are met when connecting the isolated path segments. Procedures are developed here with this capability for an around-the-singularity path. Choosing between the through and around-singularity alternatives offers the overall optimum.
Geometric Nonlinear Effect on Biaxial Bending Strength of Thin Silicon Die in the Ball-on-Ring Test
Authors: Tsai M. Y. , Liu H. Y.
Published: May 2021

The ball-on-ring (BoR) test, one of the most popular biaxial bending tests, is thoroughly investigated in this study for determining the bending strength of thin silicon dies. The application of this test method with a linear theory to the thin dies is also reevaluated using a nonlinear finite element method (NFEM) by taking into account the geometric nonlinearities, including large-deflection (global) and contact (local) nonlinearities. Mechanics of the BoR test is also discussed in terms of geometric linearity and nonlinearity. It is found that the bending strength calculated by the existing linear theory for the BoR test is still valid for the nonthin die specimens, but not for thin ones. The reason is that the thin-die specimens in the test suffer a contact-nonlinearity effect, due to a maximum applied stress moving away from the loading pin center during the loading process. The global geometric nonlinear (large-deflection) behavior occurring in the three-point bending test is not observed in the test. For applications, the fitting equations of the maximum stress in terms of applied load are proposed based on the NFEM results. Those fitting equations only depend on the specimen thickness, the head radius of the loading pin, and the elastic modulus of the specimen, but not on the specimen radius, a supporting ring radius and the head radius of the ring. The 110 μm and 160 μm-thick silicon dies in the BoR test are also demonstrated with the related fitting equations.
Holocene sedimentary architecture and paleoclimate variability at Mono Lake, California
Authors: Zimmerman* S.R.H. , Hemming S.R. , Starratt S.W.
Published: May 2021

Mono Lake occupies an internally drained basin on the eastern flank of the Sierra Nevada, and it is sensitive to climatic changes affecting precipitation in the mountains (largely delivered in the form of snowpack). Efforts to recover cores from the lake have been impeded by coarse tephra erupted from the Mono Craters, and by disruption of the lake floor due to the uplift of Paoha Island ~300 yr ago. In this study, we describe the stratigraphy of cores from three recent campaigns, in 2007, 2009, and 2010, and the extents and depths of the tephras and disturbed sediments. In the most successful of these cores, BINGO-MONO10-4A-1N (BINGO/10-4A, 2.8 m water depth), we used core stratigraphy, geochemistry, radiocarbon dates, and tephrostratigraphy to show that the core records nearly all of the Holocene in varying proportions of detrital, volcanic, and authigenic sediment. Both the South Mono tephra of ca. 1350 cal yr B.P. (calibrated years before A.D. 1950) and the 600-yr-old North Mono–Inyo tephra are present in the BINGO/10-4A core, as are several older, as-yet-unidentified tephras. Laminated muds are inferred to indicate a relatively deep lake (≥10 m over the core site) during the Early Holocene, similar to many records across the region during that period. The Middle and Late Holocene units are more coarsely bedded, and coarser grain size and greater and more variable amounts of authigenic carbonate detritus in this interval are taken to suggest lower lake levels, possibly due to lower effective wetness. A very low lake level, likely related to extreme drought, is inferred to have occurred sometime between 3500 and 2100 cal yr B.P. This interval likely corresponds to the previously documented Marina Low Stand and the regional Late Holocene Dry Period. The BINGO/10-4A core does not preserve a complete record of the period encompassing the Medieval Climate Anomaly, the Little Ice Age, and the historical period, probably due to erosion because of its nearshore position.
Male to hermaphrodite sex change in gametophytes of the fernCeratopteris richardiiis affected by hermaphrodite density, male age, and male size
Authors: Ganger Michael T. , Wilczynski Sam , Bronder Melissa
Published: May 2021

Gametophytes of the fern Ceratopteris richardii Brongn. are either male or hermaphrodite. The presence of hermaphrodite-secreted antheridiogen influences gametophytes to develop as male (induction), while its absence leads to hermaphrodite development. Males require the continued presence of antheridiogen to remain male. Removal of males from antheridiogen leads to sex change (conversion) of males to hermaphrodites. The density of hermaphrodites that males were exposed to and the amount of time males were exposed to antheridiogen were experimentally manipulated to determine whether conversion time was affected. Analysis of covariance was employed with male size serving as a covariate. The results suggest that males continuously sample the neighborhood for information regarding the density of hermaphrodites by perceiving hermaphrodite-secreted antheridiogen, then use this information to determine whether to convert to hermaphrodite. Larger males converted faster than smaller males, suggesting a potential for smaller males to remain male once larger males convert. Conversion time was longer in males grown in higher densities of hermaphrodites and shorter in males exposed to antheridiogen for a longer time, suggesting that males increase sensitivity to antheridiogen with higher doses but decrease sensitivity as they age. It is thought that such “decision making” is important for C. richardii populations to maintain beneficial sex ratios.
On the existence of marginally trapped tubes in spacetimes with local rotational symmetry
Authors: Sherif Abbas
Published: May 2021

Let M be a locally rotationally symmetric spacetime with at least one of the rotation or spatial twist being non-zero. It is proved that M cannot admit a non-minimal marginally trapped tube of the form $$\chi =X(t)$$

χ
=
X
(
t
)

.
Massive scalar field perturbation on Kerr black holes in dynamical Chern–Simons gravity
Authors: Zhang Shao-Jun
Published: May 2021

We study massive scalar field perturbation on Kerr black holes in dynamical Chern–Simons gravity by performing a $$(2+1)$$

(
2
+
1
)

-dimensional simulation. Object pictures of the wave dynamics in time domain are obtained. The tachyonic instability is found to always occur for any nonzero black hole spin and any scalar field mass as long as the coupling constant exceeds a critical value. The presence of the mass term suppresses or even quench the instability. The quantitative dependence of the onset of the tachyonic instability on the coupling constant, the scalar field mass and the black hole spin is given numerically.
Optimal Scale of Hierarchical Image Segmentation with Scribbles Guidance for Weakly Supervised Semantic Segmentation
Authors: Al-Huda Zaid , Zhai Donghai , Yang Yan , Algburi Riyadh Nazar Ali
Published: May 2021

Deep convolutional neural networks (DCNNs) trained on the pixel-level annotated images have achieved improvements in semantic segmentation. Due to the high cost of labeling training data, their applications may have great limitation. However, weakly supervised segmentation approaches can significantly reduce human labeling efforts. In this paper, we introduce a new framework to generate high-quality initial pixel-level annotations. By using a hierarchical image segmentation algorithm to predict the boundary map, we select the optimal scale of high-quality hierarchies. In the initialization step, scribble annotations and the saliency map are combined to construct a graphic model over the optimal scale segmentation. By solving the minimal cut problem, it can spread information from scribbles to unmarked regions. In the training process, the segmentation network is trained by using the initial pixel-level annotations. To iteratively optimize the segmentation, we use a graphical model to refine segmentation masks and retrain the segmentation network to get more precise pixel-level annotations. The experimental results on Pascal VOC 2012 dataset demonstrate that the proposed framework outperforms most of weakly supervised semantic segmentation methods and achieves the state-of-the-art performance, which is [Formula: see text] mIoU.
Evaluation of Livable City Based on GIS and PSO-SVM: A Case Study of Hunan Province
Authors: Li Qizhen , Fu Qian , Zou Yi , Hu Xijun
Published: May 2021

Under the background of accelerating urbanization and increasing stress of ecological environment, the construction of livable city has attracted extensive attention and become a hot spot in the study of urban problems in the world. The evaluation of livable city is a reference for the comparison of urban development and also one of the evaluation criteria for the comparison of urban competitiveness. This paper focuses on three different evaluation factors of ecological environment, economic development and public service to construct an evaluation model of environmental quality of livable cities. Then particle swarm optimization (PSO) is introduced to optimize the parameters of support vector machine (SVM), and a SVM algorithm based on PSO (PSO-SVM) is proposed to solve the livable city evaluation model. Finally, the spatial analysis combined with ArcGIS software obtained the livable city evaluation and division results of Hunan Province. The results show that PSO-SVM algorithm is superior to SVM, BA-SVM, GA-SVM, and has the advantages of faster speed and higher classification accuracy.
Radar Waveform Design Based on Multi-Agent Reinforcement Learning
Authors: Yang Qingpei , Han Zhuangzhi , Wang Han , Dong Jian , Zhao Yang
Published: May 2021

Under the actual combat background, prior information on radar targets has great uncertainty. The waveform designed based on prior information does not meet the requirements for the estimation of parameter. Thus, an algorithm for designing a waveform based on reinforcement learning is proposed to solve the above-mentioned problem. The problem on radar target parameter estimation is modeled as a framework for multi-agent reinforcement learning. Each frequency band acts as an agent, collectively interacts with the environment, independently receives observation results, shares rewards, and constantly updates the Q-network. The results of the simulation experiments indicate that the algorithm exhibits a significant improvement in terms of the mutual information obtained using the water injection method. In the case of simulation experiment, the SINR of the waveform designed based on multi-agent reinforcement learning is more than 3[Formula: see text]dB higher than that of LFM waveform. Under the condition of different time width and power, the mutual information obtained by the algorithm is better than that of water injection method. Moreover, such algorithm is also found to effectively improve the parameter estimation performance of target detection.
Analysis of the Correlation between Static Visual Stimuli, Eye Movements, and Brain Signals
Authors: Namazi Hamidreza , Menon Avinash , Krejcar Ondrej
Published: May 2021

Analysis of the correlation among the activities of the eyes and brain is an important research area in physiological science. In this paper, we analyzed the correlation between the reactions of eyes and the brain during rest and while watching different visual stimuli. Since every external stimulus transfers information to the human brain, and on the other hand, eye movements and EEG signals contain information, we utilized Shannon entropy to evaluate the coupling between them. In the experiment, 10 subjects looked at 4 images with different information contents while we recorded their EEG signals and eye movements simultaneously. According to the results, the information contents of eye fluctuations, EEG signals, and visual stimuli are coupled, which reflect the coupling between the brain and eye activities. Similar analyses could be performed to evaluate the correlation among the activities of other organs versus the brain.
The threshold for a stochastic within-host CHIKV virus model with saturated incidence rate
Authors: Gokila C. , Sambath M.
Published: May 2021

This paper deals with stochastic Chikungunya (CHIKV) virus model along with saturated incidence rate. We show that there exists a unique global positive solution and also we obtain the conditions for the disease to be extinct. We also discuss about the existence of a unique ergodic stationary distribution of the model, through a suitable Lyapunov function. The stationary distribution validates the occurrence of disease; through that, we find the threshold value for prevail and disappear of disease within host. With the help of numerical simulations, we validate the stochastic reproduction number [Formula: see text] as stated in our theoretical findings.
Revisiting polyanionic LiFePO4 battery material for electric vehicles
Authors: Lu Liming , Jiang Guoqiang , Gu Chunyan , Ni Jiangfeng
Published: May 2021

Although oxide cathodes have been widely used in these Li-ion batteries, these cathodes suffer from instability of the oxygen close-packed structure. In contrast, polyanionic phosphates such as LiFePO4 have incredible lattice stability and safety features owing to the strong covalent bond of P–O, which constrains the oxygen atoms and minimizes the defects of the oxygen site, resulting in stable frameworks. In addition, the presence of the strong P–O covalent bond stabilizes the anti-bonding transitional metal redox couple through an M–O–P inductive effect to generate a relatively high potential. Hence, polyanionic LiFePO4 has been an ideal choice of cathode materials for batteries deployed in electric vehicles. In this review, we revisit the basic features and development of LiFePO4, as an attempt to speeding its future deployment in massive electric vehicles.
Low-Rank Iteration Schemes for the Multi-Frequency Solution of Acoustic Boundary Element Equations
Authors: Baydoun Suhaib Koji , Voigt Matthias , Marburg Steffen
Published: May 2021

The implicit frequency dependence of linear systems arising from the acoustic boundary element method necessitates an efficient treatment for problems in a frequency range. Instead of solving the linear systems independently at each frequency point, this paper is concerned with solving them simultaneously at multiple frequency points within a single iteration scheme. The proposed concept is based on truncation of the frequency range solution and is incorporated into two well-known iterative solvers - BiCGstab and GMRes. The proposed method is applied to two acoustic interior problems as well as to an exterior problem in order to assess the underlying approximations and to study the convergence behavior. While this paper provides the proof of concept, its application to large-scale acoustic problems necessitates efficient preconditioning for multi-frequency systems, which are yet to be developed.
Telehealth Interventions for Family Caregivers of Persons with Chronic Health Conditions: A Systematic Review of Randomized Controlled Trials
Authors: Graven Lucinda J. , Glueckauf Robert L. , Regal Rachel A. , Merbitz Nancy K. , Lustria Mia L. A. , James Brittny A.
Published: May 2021

Objective. The purpose of this study was to provide an in-depth analysis of the components and outcomes of telehealth interventions for family caregivers of individuals with chronic health conditions. Methods. A systematic review of 17 databases was conducted for randomized controlled trials published between January 2002 and January 2017. Interventions were analyzed based on type of telecommunication modality, caregiver and care recipient characteristics, intervention components, and caregiver outcomes. Results. A total of 57 articles met criteria for inclusion. Telephone was the most frequently used mode of telehealth delivery and focused primarily on caregivers of older adults with dementia and stroke. Skills training was the most prevalent treatment strategy across telephone, web, and combined telephone and web modalities. Improved psychological functioning was reported most frequently across telehealth modalities. Conclusion. Telehealth is an effective tool in delivering caregiver interventions and leads to significant improvement in caregiver outcomes. Telephone was used most often to deliver cognitive-behavioral and psychoeducational strategies as compared to web and combined telephone and web modalities. Further research is needed to examine the effects of telehealth interventions on caregiving skills and self-efficacy, as well as health outcomes.
Study on the High-Birefringence Hollow-Core Anti-Resonant Fiber with Semicircular Cladding
Authors: Liu Shuo , Li Yuanwei , Ma Rui , Zhao Linwan , lv Jiaqi , Dong Xiaolong
Published: May 2021

For the purpose of satisfying the demands of polarization-maintaining fibers for fiber optic gyroscopes, this article proposes a semicircular cladding birefringent hollow-core anti-resonant fiber. The influence of structural parameters on the birefringence, loss, and bending loss of the fiber is studied. The simulation results demonstrate that at 1550 nm, the ultimate loss of the fundamental mode of x and y polarization is 1.76 dB/m and 0.93 dB/m, respectively. The birefringence can reach 1 × 10−4, and the wavelength range of birefringence greater than 10−4 can reach 60 nm. This indicates that it has excellent bending properties. The proposed optical fiber has excellent performance in polarization maintenance and can supply ideas for the research of high-precision fiber optic gyroscopes and other optical devices.
Some Generalizations of Frames in Hilbert Modules
Authors: Rossafi Mohamed , Kabbaj Samir
Published: May 2021

Frames play significant role in various areas of science and engineering. In this paper, we introduce the concept of frames for the set of all adjointable operators from

ℋ

to

K

and their generalizations. Moreover, we obtain some new results for generalized frames in Hilbert modules.
Information Security Terminal Architecture of Power Transportation Mobile Internet of Things Based on Big Data Analysis
Authors: Tang Xianzhi , Ding Chunyan
Published: May 2021

The progress of the social economy and the rapid development of the power field have created more favorable conditions for the construction of my country’s power grid. In this network age, how to further realize the connection between the power system and the Internet of Things is the key content of many scholars’ research. In the Internet of Things environment, there have been many excellent results in the collection, storage, and management of electric power big data, but the problem of information security has not been completely solved. Based on big data analysis and Internet of Things technology, this paper studies the architecture design of power information security terminals. In view of the diverse types of power grid mobile information and the large amount of data, this paper designs a power transportation mobile information security management system structure, which improves the effective management of power data by the system through big data, smart sensors, and wireless communication technology. According to the experiment, the power information security terminal constructed in this paper can effectively reduce communication resources and save communication costs in the process of aggregating multidimensional data. In the user satisfaction survey, residents’ satisfaction with the convenience and safety of the intelligent power system is also as high as 9.312 and 9.233. On the whole, the application of big data and Internet of Things technology to the construction of power information security terminals can indeed improve the service efficiency of power companies under the premise of ensuring safety and allow users to have a better experience.
A Novel MPE‐LPP‐ELM Recognition Method for the Fault Diagnosis of Spiral Bevel Gears
Authors: Lingli Jiang , Hongchuang Tan , Xuejun Li , Dalian Yang
Published: May 2021

Spiral bevel gears are basic transmission components which are widely used in mechanical equipment. These components are important elements used in the monitoring and diagnosis of running states for ensuring the safe operations of entire equipment setups. The vibration signals of spiral bevel gears are typically quite complicated, as they present both nonlinear and nonstationary characteristics. In previous studies, multiscale permutation entropy (MPE) has been proven to be an effective nonlinear analysis tool for complexity and irregularity evaluations of complex mechanical systems. Therefore, it is considered that MPE values can be used as the sensitive features for spiral bevel gears fault identifications. However, if the MPEs are used to directly construct the feature vectors, some problems will be encountered, such as large numbers of characteristic quantities, high dimensions, and issues related to diagnosis accuracy and efficiency, which have been proven difficult to obtain at the same time. In order to improve the accuracy and efficiency of fault recognition in spiral bevel gear evaluations, locality preserving projection (LPP) methods can be applied to reduce the high dimensionality feature vectors constructed by MPEs. They have the ability to extract low‐dimensional sensitive information from high‐dimensional feature data. In order to directly obtain the diagnostic results, classifications are necessary. When compared with traditional neural networks, it has been found that extreme learning machines (ELMs) have the advantages of faster training speeds and stronger learning abilities. In summary, this study proposed the use of MPE values which could be optimized and dimensionality reduced by LPP as the feature vectors, along with ELMs as the classifiers of the fault mode identifications, in order to carry out valuable research of fault diagnosis methods for spiral bevel gears. The proposed method was applied to the diagnoses of four types of fault state spiral bevel gears. Then, the MPE‐LPP‐ELM results were compared with those obtained using MPE‐PCA‐ELM and MPE‐ELM methods. Their respective diagnostic accuracy is 100%, 98.75%, and 98.75%, and diagnostic time is 0.0023 s, 0.0033 s, and 0.0078 s. It was determined in this study that the results confirmed the accuracy and superiority of the proposed method.
Qiyusanlong Formula Induces Autophagy in Non-Small-Cell Lung Cancer Cells and Xenografts through the mTOR Signaling Pathway
Authors: Gao Yating , Wang Xinheng , Yang Qinjun , Wang Xiaole , Zhang Xingxing , Tong Jiabing , Yang Cheng , Wu Di , Li Zegeng
Published: May 2021

Objective. Qiyusanlong (QYSL) formula has been used in the clinic for more than 20 years and has been proved to have pronounced efficacy in the treatment of non-small-cell lung cancer (NSCLC). This work aims to evaluate the molecular mechanism of QYSL formula action on NSCLC, specifically in relation to autophagy induction. Methods. In vitro, CCK-8 was used to detect the effect of QYSL serum on cell viability in A549 cells. In vivo, A549 cells were implanted subcutaneously in nude mice to establish a xenograft model. TUNEL staining was used to measure cell apoptosis and TEM to observe the autophagy-related morphological changes in vitro and in vivo. Western blotting, RT-qPCR, and immunofluorescence were used to measure autophagy-related proteins. In addition, rapamycin (an inhibitor of mTOR and inducer of autophagy) and MHY1485 (an activator of mTOR and inhibitor of autophagy) were used to determine whether QYSL-induced autophagy was regulated by the mTOR pathway. Results. QYSL serum inhibited the cell viability of A549 cells in a concentration‐dependent manner. In vivo, the QYSL formula inhibited xenograft growth. The QYSL formula promoted apoptosis in A549 cells and induced autophagosome formation in vitro and in vivo. In addition, the QYSL formula downregulated the expression of mTOR and p62, while it upregulated the expression of ATG-7 and Beclin-1 and increased the LC3-II/LC3-I ratio. QYSL serum inhibited p-mTOR in a similar manner to rapamycin while reducing the activating effects of MHY1485 on p-mTOR. Conclusion. The QYSL formula has anti-lung cancer effects and promotes autophagy through the mTOR signaling pathway.
A Rare Case of Pyogenic Granuloma in the Tooth Extraction Socket
Authors: Iijima Yosuke , Nakayama Nami , Kashimata Leona , Yamada Miki , Kawano Ryutaro , Hino Shunsuke , Kaneko Takahiro , Horie Norio
Published: May 2021

Pyogenic granuloma (PG) refers to a common, acquired, benign, and vascular tumor that arises in tissues such as the skin and mucous membranes. However, it is extremely rare for PG to arise from an empty socket after tooth extraction. Herein, we describe a rare case of PG that arose from the empty extraction socket of the second molar adjacent to a dentigerous cyst of the left mandibular wisdom tooth in a 57-year-old man. The patient’s second molar was extracted during the same procedure in which the wisdom tooth and cyst were removed. Subsequently, at 42 days after surgery, an exophytic mass was found in the socket of the second molar. An excisional biopsy was performed, and the histopathological diagnosis was PG. Since the PG recurred 90 days after the surgery, a complete excision with bone curettage was performed. During the 12 months of follow-up, there has been no recurrence observed. In conclusion, as tooth extraction is a routine dental practice, clinicians should be aware that PGs can also develop from an extraction socket.
A Detection Approach for Vulnerability Exploiter Based on the Features of the Exploiter
Authors: Hu Jinchang , Chen Jinfu , Ali Sher , Liu Bo , Chen Jingyi , Zhang Chi , Yang Jian
Published: May 2021

With the wide application of software system, software vulnerability has become a major risk in computer security. The on-time detection and proper repair for possible software vulnerabilities are of great importance in maintaining system security and decreasing system crashes. The Control Flow Integrity (CFI) can be used to detect the exploit by some researchers. In this paper, we propose an improved Control Flow Graph with Jump (JCFG) based on CFI and develop a novel Vulnerability Exploit Detection Method based on JCFG (JCFG-VEDM). The detection method of the exploit program is realized based on the analysis results of the exploit program. Then the JCFG is addressed through combining the features of the exploit program and the jump instruction. Finally, we implement JCFG-VEDM and conduct the experiments to verify the effectiveness of the proposed method. The experimental results show that the proposed detection method (JCFG-VEDM) is feasible and effective.
Masked Face Recognition Algorithm for a Contactless Distribution Cabinet
Authors: Wu GuiLing
Published: May 2021

A contactless delivery cabinet is an important courier self-pickup device, for the reason that COVID-19 can be transmitted by human contact. During the pandemic period of COVID-19, wearing a mask to take delivery is a common application scenario, which makes the study of masked face recognition algorithm greatly significant. A masked face recognition algorithm based on attention mechanism is proposed in this paper in order to improve the recognition rate of masked face images. First, the masked face image is separated by the local constrained dictionary learning method, and the face image part is separated. Then, the dilated convolution is used to reduce the resolution reduction in the subsampling process. Finally, according to the important feature information of the face image, the attention mechanism neural network is used to reduce the information loss in the subsampling process and improve the face recognition rate. In the experimental part, the RMFRD and SMFRD databases of Wuhan University were selected to compare the recognition rate. The experimental results show that the proposed algorithm has a better recognition rate.
Prognostic Value of Blood Urea Nitrogen/Creatinine Ratio for Septic Shock: An Analysis of the MIMIC‐III Clinical Database
Authors: Han Didi , Zhang Luming , Zheng Shuai , Xu Fengshuo , Li Chengzhuo , Yang Rui , Ma Wen , Yin Haiyan , Lyu Jun
Published: May 2021

Background. Research has previously been done into the risk factors for mortality in septic shock patients. However, there has been no epidemiological study investigating the effect of the blood urea nitrogen/creatinine ratio (BCR) on the prognosis of critically ill septic shock patients. This study is aimed at determining the relationship between BCR and all‐cause mortality in adult septic shock patients. Methods. Data were extracted from the MIMIC‐III database. The clinical endpoints were 28‐, 90‐, and 365‐day all‐cause mortality rates in critically ill septic shock patients. Cox proportional hazards models and subgroup analyses were used to analyze the relationship between BCR quartiles and all‐cause mortality in septic shock patients. Receiver operator characteristic (ROC) curves and areas under the ROC curves (AUCs) were calculated to evaluate how accurately BCR predicts the mortality of septic shock patients. Results. Among the 2484 septic shock patients extracted from the database, 619, 563, 677, and 625 fell into the first (<14.4 mg/dL), second (≥14.4 mg/dL and <20.0 mg/dL), third (≥20.0 mg/dL and <27.3 mg/dL), and fourth (≥27.3 mg/dL) quartiles of BCR, respectively. Male and white patients accounted for 53.8% (1336 patients) and 74.8% (1857 patients) of the population, respectively. The mean age of the population was 67.7 ± 15.8 years. An inverse M‐shaped relationship between BCR and mortality in septic shock patients was identified, with a value of ≥27.3 mg/dL providing the highest risk (HR = 1.596, 95% CI: 1.396‐1.824, P < 0.001). In the Cox regression model adjusted for different confounding variables, BCR values in the fourth quartiles were significantly associated with increased mortality, using the first quartiles as a reference. The areas under the ROC curves (AUCs) for BCR plus the Sequential Organ Failure Assessment (SOFA) score and BCR plus Acute Physiology Score III (APSIII) were 0.694 (95% CI: 0.673‐0.716) and 0.724 (95% CI: 0.703‐0.744), respectively. Conclusion. An inverse M‐shaped curve was determined between BCR and the mortality of septic shock patients. BCR was identified as a readily available and independent prognostic biomarker for septic shock patients, and higher BCRs were associated with increased mortality in these patients.
Referral Activity in Three Store-and-Forward Networks during the COVID-19 Coronavirus Pandemic
Authors: Wootton Richard , Otero Hansel , Moretti Meghan
Published: May 2021

We surveyed three well-established store-and-forward telemedicine networks to identify any changes during the first half of 2020, which might have been due to the effect of the COVID-19 coronavirus pandemic on their telemedicine operations. The three networks all used the Collegium Telemedicus system. Various quantitative performance indicators, which included the numbers of referrals and the case-mix, were compared with their values in previous years. Two of the three networks surveyed (A and B) provided telemedicine services for any type of medical or surgical case, while the third (network C) handled only pediatric radiology cases. All networks operated in Africa, but networks A and C also provided services in other resource-constrained regions. Two of the networks (networks B and C) used local staff to submit referrals, while network A relied mainly on its expatriate staff. During the first half of 2020, the numbers of referrals received on network B increased substantially, while in contrast, the numbers of referrals on network A declined. All three networks had relatively stable referral rates during 2018 and 2019. All three networks delivered a service that was rated highly by the referrers. One network operated at relatively high efficiency compared to the other two, although it is not known if this is sustainable. The networks which were more reliant on local referrers saw little reduction—or even an increase—in submitted cases, while the network that had the most dependence on international staff saw a big fall in submitted cases. This was probably due to the effect of international travel restrictions on the deployment of its staff. We conclude that organizations wanting to build or expand their telemedicine services should consider deliberately empowering local providers as their referrers.