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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.
A new species of Paurodontoides, P. siddiqii n. sp., is described and illustrated based on its morphological, morphometric, and molecular characters. The new species is characterized by a female 550–729 μm long, lip region continuous with body contour, stylet length 7.0–8.0 μm long or c. 1.0–1.2 times the lip region diameter, lateral fields with four smooth incisures, excretory pore at 85–125 μm from anterior end located at the base of the pharyngeal bulb or posterior to it, basal pharyngeal bulb with a short posterior extension projecting into the intestine, monodelphic–prodelphic reproductive system with prominent 19–22 μm long post-uterine sac, and elongate conoid tail with a filiform terminus. The new species is compared with two known species of the genus. It differs from the type species of the genus, P. linfordi, by having slightly shorter stylet, lateral field with smooth incisures, different position of the excretory pore, and absence of male. Compared to P. latus, the new species has a shorter body, shorter stylet, different position of the excretory pore, female tail shape and absence of male. The new species was also compared with close species of the genus Paurodontus because of lateral field marked with four lines, asymmetrical stylet knobs and absence of male. Molecular phylogenetic studies of the new species using partial sequences of 18S rDNA revealed that it forms a clade with a species of the genus Ficotylus. In phylogenetic analyses using partial sequences of the 28S rDNA D2-D3 domain, the new species formed a monophyletic group with a species of the genus Veleshkinema and Sphaerularia spp. (Sphaerulariinae).
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.
An experimental investigation into laser ablation of secondary explosives, cyclotetramethylene tetranitramine (HMX), has been carried out by using a solid-state laser at the wavelength of 1064 nm. The ion particles of decomposition were detected by using a time-of-flight mass spectrometer. Possible attributions of both negative ions and positive ions were obtained. Some obvious peaks were found at m/z = 18, 28, 46, 60, and 106, corresponding to H2O, CO/N2/H2CN, NO2, CH2NO2/N2O2, and N(NO2)2/CH2(NO2)2, respectively. According to the distribution of the particles, three possible pathways were proposed to explain the process of particles. The results may shed some light on the possible decomposition mechanism of HMX under laser initiation.
Background: Historically, description of patient visual acuity and visual field changes following intracranial procedures has been very rudimentary. Clinicians and researchers have relied on the use of vague descriptions like “improved”, “worsened”, and “unchanged” to describe outcomes following resections of tumours affecting the optic apparatus, which are difficult to quantify in a clinical setting. Methods: We present a novel way to describe a patient’s visual function as a combination of visual acuity and visual field assessment that is simple to use and can be used by surgeons, and researchers to gauge visual outcomes following tumour resection. Results: With our scale we were able to capture the overall visual change while being sensitive enough to define the overall quantity of improvement or worsening quantitatively, using categories that are clinically relevant and understandable. Conclusions: The implementation of pre- and post- operative assessment provides clinically relevant information for surgeons and is robust for routine use.
The objective of this study was to evaluate the potential of using Multiplex 3, a hand-held canopy fluorescence sensor, to determine rice nitrogen (N) status at different growth stages. In 2013, a paddy rice field experiment with five N fertilizer treatments and two varieties was conducted in Northeast China. Field samples and fluorescence data were collected simultaneously at the panicle initiation (PI), stem elongation (SE), and heading (HE) stages. Four N status indicators, leaf N concentration (LNC), plant N concentration (PNC), plant N uptake (PNU) and N nutrition index (NNI), were determined. The preliminary results indicated that different N application rates significantly affected most of the fluorescence variables, especially the simple fluorescence ratios (SFR_G, SFR_R), flavonoid (FLAV), and N balance indices (NBI_G, NBI_R). These variables were highly correlated with N status indicators. More studies are needed to further evaluate the accuracy of rice N status diagnosis using fluorescence sensing at different growth stages.
Previous studies have investigated the association between dietary inflammatory potential and the development of cancer. For breast cancer the results have been equivocal. The present study aimed to investigate whether higher Dietary Inflammatory IndexTM (DII) scores were associated with increased risk of breast cancer among Chinese women. A total of 867 cases and 824 controls were recruited into the present case–control study from September 2011 to February 2016. DII scores were computed based on baseline dietary intake assessed by a validated 81-item FFQ. The OR and 95 % CI were assessed by multivariable logistic regression after adjusting for various potential confounders. DII scores in this study ranged from −5·87 (most anti-inflammatory score) to +5·71 (most proinflammatory score). A higher DII score was associated with a higher breast cancer risk (adjusted ORquartile 4 v. 1 2·28; 95 % CI 1·71, 3·03; adjusted ORcontinuous 1·40; 95 %CI 1·25, 1·39). In stratified analyses, positive associations also were observed except for underweight women or women with either oestrogen receptor+ or progesterone receptor+ status (but not both). Results from this study indicated that higher DII scores, corresponding to more proinflammatory diets, were positively associated with breast cancer risk among Chinese women.
The 2083 m Vostok Antarctic ice core provides a unique opportunity for access to many paleoclimatic and paleo-environmental proxy data. This core, which has been dated by using a glaciological model, fully covers the last glacial-interglacial cycle, and goes back to the ice age which preceded the last interglaciai (−160 ka B P ).
A continuous deuterium record is now available and we have interpreted it in terms of local temperature changes. This record is dominated by the large 100 ka glacial-inter-glacial oscillation, with a maximum temperature amplitude of about 11°C; the long Last Glacial period is very well documented and it is confirmed that the warmest part of the Last Interglaciai period was about 2°C warmer than the Holocene. Comparison with the ice-volume marine record shows that the Vostok climate record is of relatively large geographical significance, which makes it possible to establish, over the last 160 ka, the link between worldwide climatic changes and the Vostok dust record that we present here.
This dust content corresponds to the non-soluble microparticles. It was obtained on a discontinuous basis (1 sample = about ∼10 m). Due to the very low concentration of some samples (down to 20 x 10−9gg−1) and cracks in the ice from the first 1000 m depth, we used stringent decontamination procedures. Size distribution and total concentration were measured, using a Coulter counter and an optical microscope; the results were tested against chemical measurements (aluminium concentration). In previous studies, it has been shown that the main proportion of insoluble microparticles is of terrigenous origin and represents the small-sized (radius <2 μm) dust produced on the continents.
The Vostok record displays an increase in dust concentration of up to 20 times during the coldest climatic periods, coupled with the presence of larger particles. It confirms, on a much longer time-scale, a characteristic previously noted in Antarctic and Greenland ice cores over the Last Glacial Maximum. This large increase is attributed to a greater areal extent of global tropical aridity during the cold periods, coupled with higher efficiency of atmospheric circulation in respect of dust production and transport. Beyond this, the relationship between the dust input and the successive stages during the Last Glacial is now very well documented and will be discussed with a view to correlating the Vostok climatic record with other marine and terrestrial paleodata.
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.
A new death line for radio pulsars is presented in this paper within the framework of vacuum gap and inverse Compton scattering (ICS) induced pair production process. The 8.5s period pulsar PSR J2144-3933 is located above the death line without any additional assumptions. An “appearance line” instead of the so-called “Hubble line”, is also presented in this paper. Both of those two lines fit observations well.
While the chief function and methods of operation of the Commission have remained much the same as in the past, there has been a gradual evolution in the nature of the proposals submitted. A greater fraction now come from countries in which the study of astronomy on a professional basis is as yet very recent and more proposals are being received from relatively young astronomers, although admittedly the distinction between a “young” and an “established” astronomer is not always easy to make. The commission may wish to consider whether or not it is advisable to reconsider its guidelines. Grants awarded during the interval 30 November 1981 and 31 January 1985 were the following.
In preparing the present report, which covers the period July 1, 1981, to June 30, 1984, close collaboration has taken place between Commissions 10 and 12, the two solar commissions, in order to avoid duplications and to insure that pertinent subjects are treated. The reader is referred to the report of Commission 12 for further solar topics. It is a pleasure to acknowledge the excellent work of the reviewers who wrote the different sections of this report, and all the members of the commission who provided information on research to be included.
For the members of the compact group of galaxies Shahbazian 4 the radial velocities are defined. The velocity dispersion is 440 km s−1. Moreover the appparent and absolute magnitudes of galaxies in the V band as well as the mass-to-luminosity ratio are obtained. The latter is approximately 220 M⊙/L⊙. The “crossing time” for the group Shahbazian 4 is equal to 4.7 × 107 years. It is one of the densest group of galaxies with n ~ 104 galaxies Mpc−3.
In late 2010, the online services giant Google released a tool for public use called the Google Books Ngram Viewer. The Ngram viewer was a Web interface that enabled virtually anyone with an Internet connection to run frequency searches of character strings in a corpus of more than 5.2 million digitized books, or roughly 500 billion words, published between the sixteenth and twenty-first centuries. With these massive corpora at hand, a new branch of humanistic research has been established, dubbed “culturomics” (Michel et al., 2011). Culturomics enables investigators to examine changes over time reflected in print material associated with the lexicon being used and can offer evidence of social patterns and orientations within a language community. For example, one could use the Ngram viewer to chart how often the word “slavery” was printed over time and see that it increased dramatically in the years leading up to the US Civil War and had since declined substantially. Similarly, one could look at the appearance of technological innovations, such as the radio and the telephone, in print material and infer that the rate of cultural adoption of these technologies has increased over time. These kinds of capabilities are not contingent on the existence of the Ngram Viewer, but rather reflective of how analysts can look toward word usage in print materials from different times to understand changes within a community and culture (e.g., Lieberman et al., 2007).
What would such an approach tell us about the learning sciences (LS)? Granted, the field spans decades rather than centuries, and the corpus of associated text is modest even against the wide range of education research literature published during the same period of time. However, it is our suspicion that even for a field that is still emerging and establishing its academic identity, an examination of frequency of word use across different times could be informative for our understanding of the field. This chapter summarizes some of our efforts to do that work. Building upon an analysis presented in 2012 (Lee, Ye, & Recker, 2012), we provide here an elaborated comparative analysis of proceedings from the first and the most recent (at the time of this writing) LS conferences (Birnbaum, 1991; Polman et al., 2014), as well as a third conference, roughly collocated with the first LS conference (Gomez, Lyons, & Radinsky, 2010).
We aimed to investigate the prevalence and associated factors of HSV-2 discordance and concordance in HIV-1-discordant couples. This study used the baseline data from a cohort study of HIV-1-discordant couples in Dehong prefecture of Yunnan province, China. Of 954 participating couples, 42·4% were affected by HSV-2, of which 20·4% were HSV-2-concordant positive, 7·6% were HSV-2-discordant where the male was HSV-2 positive, and 14·4% were HSV-2 discordant where the female was HSV-2 positive. Compared to HSV-2-negative concordance, HSV-2 discordance with an HSV-2-positive male spouse was significantly associated with characteristics of the male spouse, including Han ethnicity and being in a second marriage. HSV-2 discordance with an HSV-2-positive female spouse was significantly associated with characteristics of the female spouse, including Han ethnicity, having engaged in commercial sex, having a sexual relationship of <3 years and being HIV-1 infected. Compared to HSV-2 discordance, HSV-2-positive concordance was significantly associated with an education level of middle school or higher for both spouses, a sexual relationship of ⩾3 years, more frequent sex and having an HIV-1-infected male spouse. The findings highlight the need for HSV-2 prevention and treatment efforts to reduce HSV-2 transmission in this population, and emphasize the importance of implementing prevention interventions early in couples' relationships.
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.