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Habitat prioritization and corridor restoration are important steps for reconnecting fragmented habitats and species populations, and spatial modelling approaches are useful in identifying suitable habitat for elusive tropical rainforest mammals. The Endangered Bornean banteng Bos javanicus lowi, a wild bovid endemic to Borneo, occurs in habitat that is highly fragmented as a result of extensive agricultural expansion. Based on the species’ historical distribution in Sabah (Malaysia), we conducted camera-trap surveys in 14 forest reserves during 2011–2016. To assess suitable habitat for the banteng we used a presence-only maximum entropy (MaxEnt) approach with 11 spatial predictors, including climate, infrastructure, land cover and land use, and topography variables. We performed a least-cost path analysis using Linkage Mapper, to understand the resistance to movement through the landscape. The surveys comprised a total of 44,251 nights of camera trapping. We recorded banteng presence in 11 forest reserves. Key spatial predictors deemed to be important in predicting suitable habitat included soil associations (52.6%), distance to intact and logged forests (11.8%), precipitation in the driest quarter (10.8%), distance to agro-forest and regenerating forest (5.7%), and distance to oil palm plantations (5.1%). Circa 11% of Sabah had suitable habitat (7,719 km2), of which 12.2% was in protected forests, 60.4% was in production forests and 27.4% was in other areas. The least-cost path model predicted 21 linkages and a relatively high movement resistance between core habitats. Our models provide information about key habitat and movement resistance for bantengs through the landscape, which is crucial for constructive conservation strategies and land-use planning.
Guangxi, a province in southwestern China, has the second highest reported number of HIV/AIDS cases in China. This study aimed to develop an accurate and effective model to describe the tendency of HIV and to predict its incidence in Guangxi. HIV incidence data of Guangxi from 2005 to 2016 were obtained from the database of the Chinese Center for Disease Control and Prevention. Long short-term memory (LSTM) neural network models, autoregressive integrated moving average (ARIMA) models, generalised regression neural network (GRNN) models and exponential smoothing (ES) were used to fit the incidence data. Data from 2015 and 2016 were used to validate the most suitable models. The model performances were evaluated by evaluating metrics, including mean square error (MSE), root mean square error, mean absolute error and mean absolute percentage error. The LSTM model had the lowest MSE when the N value (time step) was 12. The most appropriate ARIMA models for incidence in 2015 and 2016 were ARIMA (1, 1, 2) (0, 1, 2)12 and ARIMA (2, 1, 0) (1, 1, 2)12, respectively. The accuracy of GRNN and ES models in forecasting HIV incidence in Guangxi was relatively poor. Four performance metrics of the LSTM model were all lower than the ARIMA, GRNN and ES models. The LSTM model was more effective than other time-series models and is important for the monitoring and control of local HIV epidemics.
Alanyl-glutamine (Ala-Gln), a highly soluble and stable glutamine dipeptide, is known to improve gut integrity and function. The aim of this study was to evaluate whether dietary Ala-Gln supplementation could improve growth performance, intestinal development and digestive-absorption function in weaned piglets. A total of 100 purebred Yorkshire piglets weaned at 21 days of age were assigned randomly to four dietary treatment groups and fed a basal diet (control group) or a basal diet containing 0.15%, 0.30% and 0.45% Ala-Gln, respectively. Compared with the control group, piglets fed the Ala-Gln diets had higher average daily gain and lower feed : gain and diarrhea rate (P < 0.05). Moreover, dietary Ala-Gln supplementation increased villous height and villous height : crypt depth ratio in duodenum and jejunum (P < 0.05), as well as the activities of maltase and lysozyme in jejunum mucosa (P < 0.05). In addition, a decrease in serum diamine oxidase activity and crypt depth in duodenum and jejunum was observed in piglets fed the Ala-Gln diets (P < 0.05). Serum cytosolic phospholipase A2 (cPLA2) concentration and gene expression of cPLA2, Na+-dependent glucose transporter 1, glucose transporter 2 and peptide transporter 1 in jejunum were increased by feeding Ala-Gln diets relative to control diet (P < 0.05). These results indicated that feeding Ala-Gln diet has beneficial effects on the growth performance of weaned piglets, which associated with maintaining intestinal morphology and digestive-absorption function.
This paper reports a visible and thermal drone monitoring system that integrates deep-learning-based detection and tracking modules. The biggest challenge in adopting deep learning methods for drone detection is the paucity of training drone images especially thermal drone images. To address this issue, we develop two data augmentation techniques. One is a model-based drone augmentation technique that automatically generates visible drone images with a bounding box label on the drone's location. The other is exploiting an adversarial data augmentation methodology to create thermal drone images. To track a small flying drone, we utilize the residual information between consecutive image frames. Finally, we present an integrated detection and tracking system that outperforms the performance of each individual module containing detection or tracking only. The experiments show that, even being trained on synthetic data, the proposed system performs well on real-world drone images with complex background. The USC drone detection and tracking dataset with user labeled bounding boxes is available to the public.
Transition metal perovskite chalcogenides, a class of materials with rich tunability in functionalities, are gaining increased attention as candidate materials for renewable energy applications. Perovskite oxides are considered excellent n-type thermoelectric materials. Compared to oxide counterparts, we expect the chalcogenides to possess more favorable thermoelectric properties such as lower lattice thermal conductivity and smaller band gap, making them promising material candidates for high temperature thermoelectrics. Thus, it is necessary to study the thermal properties of these materials in detail, especially thermal stability, to evaluate their potential. In this work, we report the synthesis and thermal stability study of five compounds, α-SrZrS3, β-SrZrS3, BaZrS3, Ba2ZrS4, and Ba3Zr2S7. These materials cover several structural types including distorted perovskite, needle-like, and Ruddlesden–Popper phases. Differential scanning calorimeter and thermogravimetric analysis measurements were performed up to 1200 °C in air. Structural and chemical characterizations such as X-ray diffraction, Raman spectroscopy, and energy dispersive analytical X-ray spectroscopy were performed on all the samples before and after the heat treatment to understand the oxidation process. Our studies show that perovskite chalcogenides possess excellent thermal stability in air at least up to 550 °C.
Hepatitis C virus (HCV) infection is one of the leading causes of death and morbidity associated with liver disease. Risk factors identified for the transmission of HCV include contaminated blood products, intravenous drug use, body piercing, an infected mother at birth, sexual activity, and dental therapy, among others. However, the exact diversity of the HCV genotype and genetic variation among patients with low-risk factors is still unknown. In this study, we briefly described and analysed the genotype distribution and genetic variation of HCV infections with low-risk factors using molecular biology techniques. The results suggested that genotype 1b was predominant, followed by genotypes 2a and 1a. Genetic variations in the 5′ UTR sequences of HCV were identified, including point mutations, deletions, and insertions. The frequency of genetic variations in 1b was higher than in 2a. This study provides considerable value for the prevention and treatment of liver disease caused by HCV among patients with low-risk factors and for the development of HCV diagnostic reagents and vaccines.
OBJECTIVES/SPECIFIC AIMS: Key factors causing irreproducibility of research include those related to inappropriate study design methodologies and statistical analysis. In modern statistical practice irreproducibility could arise due to statistical (false discoveries, p-hacking, overuse/misuse of p-values, low power, poor experimental design) and computational (data, code and software management) issues. These require understanding the processes and workflows practiced by an organization, and the development and use of metrics to quantify reproducibility. METHODS/STUDY POPULATION: Within the Foundation of Discovery – Population Health Research, Center for Clinical and Translational Science, University of Utah, we are undertaking a project to streamline the study design and statistical analysis workflows and processes. As a first step we met with key stakeholders to understand the current practices by eliciting example statistical projects, and then developed process information models for different types of statistical needs using Lucidchart. We then reviewed these with the Foundation’s leadership and the Standards Committee to come up with ideal workflows and model, and defined key measurement points (such as those around study design, analysis plan, final report, requirements for quality checks, and double coding) for assessing reproducibility. As next steps we are using our finding to embed analytical and infrastructural approaches within the statisticians’ workflows. This will include data and code dissemination platforms such as Box, Bitbucket, and GitHub, documentation platforms such as Confluence, and workflow tracking platforms such as Jira. These tools will simplify and automate the capture of communications as a statistician work through a project. Data-intensive process will use process-workflow management platforms such as Activiti, Pegasus, and Taverna. RESULTS/ANTICIPATED RESULTS: These strategies for sharing and publishing study protocols, data, code, and results across the spectrum, active collaboration with the research team, automation of key steps, along with decision support. DISCUSSION/SIGNIFICANCE OF IMPACT: This analysis of statistical methods and process and computational methods to automate them ensure quality of statistical methods and reproducibility of research.
Diarrhea is a common cause of morbidity and mortality and the incidence of diarrhea in the world has changed little over the past four decades. To assess the prevalence of and healthcare practices for diarrhea, a cross-sectional study was conducted in Pudong, Shanghai, China. In October 2014, a total of 5324 community residents were interviewed. Respondents were asked if they had experienced diarrhea (defined as ⩾3 passages of watery, loose, bloody, or mucoid stools within a 24-h period) in the previous month prior to the interview. The monthly prevalence of diarrhea was 4·1% (95% CI: 3·3–4·8), corresponding to an incidence rate of 0·54 episodes per person-year. The proportion of individuals with diarrhea who sought healthcare was 21·2% (95% CI: 13·4–29·0). Diarrhea continues to impose a considerable burden on the community and healthcare system in Pudong. Young age and travel were identified as predictors of increased diarrhea occurrence.
This study aimed to evaluate subjective symptom changes in obstructive sleep apnoea hypopnea syndrome patients following nasal surgery, and to explore treatment efficacy in improving patient quality of life.
Patients with nasal blockage accompanied by habitual snoring were stratified into four groups. Their subjective symptoms were evaluated before and after nasal surgery.
There was a significant decrease in the nasal blockage symptom visual analogue scale, Epworth Sleepiness Scale, Snore Outcomes Survey, Spouse/Bed Partners Survey and Sino-Nasal Outcome Test 20 scores for all patients at six months after surgery. The visual analogue scale score for subjective olfactory function was significantly improved in the severe obstructive sleep apnoea hypopnea syndrome patient group.
Nasal surgery can effectively improve the subjective symptoms of patients with simple snoring accompanied by nasal blockage and of patients with obstructive sleep apnoea hypopnea syndrome, thus improving their quality of life.
EVA foams, like all other polymers, also exhibit strain-rate effects and hysteresis. However, currently available approaches for predicting the mechanical response of polymeric foam subjected to an arbitrarily imposed loading history and strain-rate effect are highly limited. Especially, the strain rates in the intermediate rate domain (between 100 and 102 s–1) are extremely difficult to study. The use of data generated through the drop tower technique for implementation in constitutive equations or numerical models has not been considered in past studies. In this study, an experiment including a quasi-static compression test and drop impact tests with a high speed camera was conducted. An inverse analysis technique combined with a finite element model for material parameter identification was developed to determine the stress–strain behavior of foam at different specific strain rates. It was used in this study to simulate multiple loading and unloading cycles on foam specimens, and the results were compared with experimental measurements.
The simulations of flow past a two-dimensional circular cylinder are conducted to investigate the feasibility of adaptive mesh refinement applied on curved spectral elements. The nonconforming spectral element method and adaptive meshes technique are used to the curve surfaces and observe whether any discontinuity of the solutions. The adaptive nonconforming spectral element method is implemented to compare with those obtained by conforming mesh method with respect to several existing numerical and experimental studies. Meanwhile, three kinds of estimated error base mesh adaptation are conducted to compare their accuracy and efficiency with conforming mesh method. The results show adaptive nonconforming mesh method is more efficient than the conforming method. Especially, the vorticity error based method performs highest accuracy and fastest convergence. The results show this mesh refinement technique is applicable on the curved elements with satisfactory accuracy. It releases this technique may be applied on the simulations of flow past objects with more general geometries.
Glyphosate-resistant (GR) horseweed has become an especially problematic
weed in different crop production systems across the United States and the
world. In this field study, we used a nondestructive measurement system to
analyze the pollen production, deposition, and dispersion of a Tennessee
glyphosate resistant (TNR) horseweed biotype in Knoxville, TN during the
2013 pollination season. We observed that the pollination season of TNR
horseweed lasted about 2 mo (54 d). About 78.93% of horseweed pollen was
released between 9:00 A.M. and 7:00 P.M. during each sampling day and the
release peak was at about 1:30 P.M. The seasonal release of pollen grains
was estimated to be 5.11 million grains plant−1. The release rate
data indicated that the integrated horizontal flux density and deposition
flux density contributed to 78.17% and 21.83% of the release rate,
respectively. We also found that pollen concentration decreased with
distance from the source field; the average pollen concentration decreased
to 50.69% at a distance of 16 m from the source plot. This is the first
result of a systematic, direct examination of the release rate (emission and
deposition), release pattern (daily and seasonal), and dispersion pattern of
GR horseweed pollen.
Floral organ development influences plant reproduction and crop yield. The mechanism of floral organ specification is generally conserved in angiosperms as demonstrated by the ‘ABC’ model. However, mechanisms underlying the development of floral organs in specific groups of species such as grasses remain unclear. In the genus Oryza (rice), a spikelet consists of a fertile floret sub-tended by a lemma, a palea, two sterile lemmas and rudimentary glumes. To understand how the lemma is formed, a curve-shaped lemma-distortion1 (ld1) mutant was identified. Genetic analysis confirmed that the ld1 mutant phenotype was due to a single recessive gene mutation. Using a large F2 population, the LD1 gene was mapped between markers Indel-7-15 and Indel-7-18, which encompassed a region of 15·6 kilo base pairs (kbp). According to rice genome annotations, two putative genes, LOC_Os07g32510 and LOC_Os07g32520, were located in this candidate region. However, DNA sequencing results indicated only 1 base pair (bp) substitution (T⇨C) was found in LOC_Os07g32510 between the wild-type and the ld1 mutant. Thus LOC_Os07g32510, encoding a DNA binding with one zinc finger (DoF) containing protein, was the candidate gene for LD1. Further analysis showed that mutation of the amino acid cysteine (C) to arginine (R) was likely to lead to zinc finger protein deactivation. Phylogenetic and conservation analysis of the gene from different species revealed that cysteine was critical to LD1 function. As a new gene controlling lemma development, the study of LD1 could provide insights into rice floral organ formation mechanisms.
Nitrogen (N) supply is essential for achieving high grain yield in maize production, but excessive N application can lead to lodging risks and potential yield loss. The main objective of the present study was to investigate the effect of ethephon application under different N fertilizer rates in reducing maize lodging. Field experiments were conducted to determine the interactive effects of ethephon (0 and 180 g/ha) and N rate (0, 75, 150 and 225 kg N/ha) on the morphological and chemical characteristics of basal internode and yield across two summer maize-growing seasons (2011/12) in Wuqiao of the North China Plain. Findings showed that ethephon significantly increased the maximum diameter of the 7th to 14th internodes, and decreased the internode lengths, which led to a decrease in plant and ear heights under different N rates. Significant ethephon × N interaction effects were observed on the diameter and length of internode, dry weight per unit internode length and breaking resistance. Ethephon significantly increased N, cellulose and hemicellulose contents of the basal internode, but cellulose and hemicellulose contents decreased as the rate of N application increased. Internode diameter, dry weight per unit internode length, and N content of the basal internode were significantly positively correlated with breaking resistance. Ethephon significantly increased grain yield and harvest index in 2011, but not in 2012. Grain yield and above-ground biomass were increased with increasing N application in both growing seasons, showing linear and quadratic responses. These results suggested that ethephon could increase stalk strength by improving the morphological and chemical characteristics of the basal internode, and maintain high yield and biomass under high N rates.
Multidrug-resistant Pseudomonas aeruginosa (MDRPA) infections are major threats to healthcare-associated infection control and the intrinsic molecular mechanisms of MDRPA are also unclear. We examined 348 isolates of P. aeruginosa, including 188 MDRPA and 160 non-MDRPA, obtained from five tertiary-care hospitals in Guangzhou, China. Significant correlations were found between gene/enzyme carriage and increased rates of antimicrobial resistance (P < 0·01). gyrA mutation, OprD loss and metallo-β-lactamase (MBL) presence were identified as crucial molecular risk factors for MDRPA acquisition by a combination of univariate logistic regression and a multifactor dimensionality reduction approach. The MDRPA rate was also elevated with the increase in positive numbers of those three determinants (P < 0·001). Thus, gyrA mutation, OprD loss and MBL presence may serve as predictors for early screening of MDRPA infections in clinical settings.
Hand, foot and mouth disease (HFMD) is an acute contagious condition caused by a spectrum of human enteroviruses. HFMD reinfection is common in the absence of cross-protection from other virus subtypes. This study focused on reinfection in children in Anhui province, China between 2008 and 2013 using surveillance system data. We classified 8960 cases as reinfected, corresponding to a rate of 2·02%. The reinfection rate was higher in boys than in girls [odds ratio (OR) 1·27, 95% confidence interval (CI) 1·21–1·32, P < 0·001], children aged < 3 years (OR 3·82, 95% CI 3·58–4·07, P < 0·001), and children living in rural areas (OR 1·09, 95% CI 1·04–1·14, P = 0·001). The reinfection rate in children who were originally infected with non-enterovirus A71 (non-EVA71) enteroviruses was higher than those infected with EVA71 (OR 1·36, 95% CI 1·02–1·80, P = 0·034). Influential factors of reinfection rate included annual incidence (β coefficient = 0·715, P = 0·002) and the proportion of EVA71 in patients with mild HFMD (β coefficient = −0·509, P = 0·018). These results demonstrate that boys aged <3 years, especially those in rural areas or regions with a lower EVA71 proportion are more prone to reinfection, and specific health education programmes should be developed to protect these susceptible populations.
Ag–reduced graphene oxide (Ag/rGO) nanoparticle composites were synthesized through a facile one-step hydrothermal reaction using GO and silver carbonate (Ag2CO3) as raw materials. The homogeneous silver nanospheres with an average size of 50 nm well dispersed on the surface of rGO were obtained without other additives. During the formation process, GO both promotes the dispersion of Ag2CO3 in aqueous solution and acts as the substrate of silver cations, and the hydrolysis of Ag2CO3 provides silver cations and alkaline condition. Moreover, GO further serves as reducing agent to generate elemental silver in the alkaline condition. The as-prepared materials exhibit excellent surface-enhanced Raman scattering activities when used to detect the Raman signals of R6G absorbed on the Ag/rGO substrate.
To evaluate the accuracy of real-time polymerase chain reaction (PCR) for Clostridium difficile–associated disease (CDAD) detection, after hospital CDAD rates significantly increased following real-time PCR initiation for CDAD diagnosis.
Hospital-wide surveillance study following examination of CDAD incidence density rates by interrupted time series design.
Large university-based hospital.
Hospitalized adult patients.
CDAD rates were compared before and after real-time PCR implementation in a university hospital and in the absence of physician and infection control practice changes. After real-time PCR introduction, all hospitalized adult patients were screened for C. difficile by testing a fecal specimen by real-time PCR, toxin enzyme-linked immunosorbent assay, and toxigenic culture.
CDAD hospital rates significantly increased after changing from cell culture cytotoxicity assay to a real-time PCR assay. One hundred ninety-nine hospitalized subjects were enrolled, and 101 fecal specimens were collected. C. difficile was detected in 18 subjects (18%), including 5 subjects (28%) with either definite or probable CDAD and 13 patients (72%) with asymptomatic C. difficile colonization.
The majority of healthcare-associated diarrhea is not attributable to CDAD, and the prevalence of asymptomatic C. difficile colonization exceeds CDAD rates in healthcare facilities. PCR detection of asymptomatic C. difficile colonization among patients with non-CDAD diarrhea may be contributing to rising CDAD rates and a significant number of CDAD false positives. PCR may be useful for CDAD screening, but further study is needed to guide interpretation of PCR detection of C. difficile and the value of confirmatory tests. A gold standard CDAD diagnostic assay is needed.