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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.
Dietary supplementation with the organic chromium (Cr) has been shown to positively affect the immune function of poultry. However, to our knowledge, no experiment has been done to directly compare the impacts of Cr chloride and chromium picolinate (CrPic) on the immune responses of broilers vaccinated with Avian Influenza (AI) virus vaccine. Therefore, the present experiment was conducted to investigate the effects of supplemental Cr sources (Cr chloride and CrPic) and levels on the growth performance and immune responses of broilers vaccinated with AI virus vaccine so as to provide an effective nutritional strategy for improving immune function of broilers. A total of 432 1-day (d)-old male broiler chicks were used in a 1 plus 2×4 design. Chickens were given either a diet without Cr supplementation (control) or diets supplemented with 0.4, 0.8, 1.6, or 3.2 mg Cr/kg as either Cr chloride or CrPic for 42 d. Compared to the control, dietary Cr supplementation had no effect (P>0.05) on average daily gain, average daily feed intake and gain : feed of broilers during the starter and grower phases, but increased (P<0.05) the relative weights of bursa of fabricius on d 21 and thymus, spleen, or bursa of fabricius on d 42, serum antibody titers against AI virus on d 21, 28, 35 and 42, blood T-lymphocyte transformation rate on d 28 and 42, blood T-lymphocyte percentage on d 42, and serum interleukin-2 contents on d 28. Broilers fed the diets supplemented with the inorganic Cr chloride had higher (P<0.05) weights of thymus, spleen and bursa of fabricius than those fed the diets supplemented with the CrPic on d 42. In addition, broilers fed the diets supplemented with the CrPic had higher (P<0.05) antibody titers against AI virus than those fed the diets supplemented with the inorganic Cr chloride on d 21 and 35. These results indicate that dietary Cr supplementation improved immune responses of broilers vaccinated with AI virus, and the inorganic Cr chloride was more effective than the CrPic in increasing the relative weights of lymphoid organs, however, the CrPic was more effective than the inorganic Cr chloride in enhancing the serum antibody titer against AI virus.
When a power module is under a continuous electrical load, a temperature effect is induced by the current load in the module configuration. The joint material therefore has long-term temperature and mechanical loadings under supplied power. A long-term temperature load can change the material and mechanical properties, including voiding, cracking, creeping and fracturing. Au/20Sn eutectic alloy, a highly temperature resistant material, is typically used for electric interconnections in high-power modules. The Au/20Sn is converted into AuSn and an Au5Sn intermetallic compound (IMC) by solid liquid inter-diffusion (SLID) bonding to form joints with high melting points. In this study, a test vehicle based on an actual power module was designed and fabricated to investigate and understand the material properties and mechanical behavior of Au/20Sn solder under a temperature load. The joint microstructure exhibited variation under different thermal treatment conditions such as temperature and load durations. The shear strength test was conducted to examine the mechanical strength of the joints under different thermal load conditions. The failure mode of the joint was further determined using fracture morphology after the shear test. Finally, the shear strength of Au/20Sn was identified to investigate the high temperature resistance of joints under different temperatures. The mechanical strengths of joints under different temperature loads are expressions of different mechanical characteristics and can be used to determine reliability at an intended high application temperature.
This study investigates numerically the performance of applying aerospike nozzle in a hydrogen peroxide mono-propellant propulsion system. A set of governing equations, including continuity, momentum, energy and species conservation equations with extended k-ε turbulence equations, are solved using the finite-volume method. The hydrogen peroxide mono-propellant is assumed to be fully decomposed into water vapor and oxygen after flowing through a catalyst bed before entering the nozzle. The aerospike nozzle is expected to have high performance even in deep throttling cases due to its self-compensating characteristics in a wide range of ambient pressure environments. The results show that the thrust coefficient efficiency (Cf,η) of this work exceeds 90% of the theoretical value with a nozzle pressure ratio (PR) in the range of 20 ~ 45. Many complex gas dynamics phenomena in the aerospike nozzle are found and explained in the paper. In addition, performance of the aerospike nozzle is compared with that of the bell-shape nozzle.
Fermented soybean meal (FSM), which has lower anti-nutritional factors and higher active enzyme, probiotic and oligosaccharide contents than its unfermented form, has been reported to improve the feeding value of soybean meal, and hence, the growth performance of piglets. However, whether FSM can affect the bacterial and metabolites in the large intestine of piglets remains unknown. This study supplemented wet-FSM (WFSM) or dry-FSM (DFSM) (5% dry matter basis) in the diet of piglets and investigated its effects on carbon and nitrogen metabolism in the piglets’ large intestines. A total of 75 41-day-old Duroc×Landrace×Yorkshire piglets with an initial BW of 13.14±0.22 kg were used in a 4-week feeding trial. Our results showed that the average daily gain of piglets in the WFSM and DFSM groups increased by 27.08% and 14.58% and that the feed conversion ratio improved by 18.18% and 7.27%, respectively, compared with the control group. Data from the prediction gene function of Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) based on 16S ribosomal RNA (rRNA) sequencing showed that carbohydrate metabolism function families in the WFSM and DFSM groups increased by 3.46% and 2.68% and that the amino acid metabolism function families decreased by 1.74% and 0.82%, respectively, compared with the control group. These results were consistent with those of other metabolism studies, which showed that dietary supplementation with WFSM and DFSM increased the level of carbohydrate-related metabolites (e.g. 4-aminobutanoate, 5-aminopentanoate, lactic acid, mannitol, threitol and β-alanine) and decreased the levels of those related to protein catabolism (e.g. 1,3-diaminopropane, creatine, glycine and inosine). In conclusion, supplementation with the two forms of FSM improved growth performance, increased metabolites of carbohydrate and reduced metabolites of protein in the large intestine of piglets, and WFSM exhibited a stronger effect than DFSM.
In this paper, finite amplitude steady-state wave groups with multiple nearly resonant interactions in deep water are investigated theoretically. The nonlinear water wave equations are solved by the homotopy analysis method (HAM), which imposes no constraint on either the number or the amplitude of the wave components, to resolve the small-divisor problems caused by near resonances. A new kind of auxiliary linear operator in the framework of the HAM is proposed to transform the small divisors associated with the non-trivial nearly resonant components to singularities associated with the exactly resonant ones. Primary components, exactly resonant components together with nearly resonant components are considered as the initial non-trivial components, since all of them are homogeneous solutions to the auxiliary linear operator. For wave groups with weak nonlinearity, the energy transfer between nearby nearly resonant components is remarkable. As the nonlinearity increases, the number of steady-state wave groups increases as more components join the near resonance. This indicates that the probability of existence of steady-state resonant waves increases with the nonlinearity of wave groups. The frequency band broadens and spectral asymmetry becomes more and more pronounced. The amplitude of each component may either increase or decrease with the nonlinearity of wave groups, while the amplitude of the whole wave group increases continuously and finite amplitude wave groups are obtained. This work shows the wide existence of steady-state waves when multiple nearly resonant interactions are considered.
The objectives of this study were to determine the effect and mode of action of Saccharomyces cerevisiae (YST2) on enteric methane (CH4) mitigation in pigs. A total of 12 Duroc×Landrace×Yorkshire male finisher pigs (60±1 kg), housed individually in open-circuit respiration chambers, were randomly assigned to two dietary groups: a basal diet (control); and a basal diet supplemented with 3 g/YST2 (1.8×1010 live cells/g) per kg diet. At the end of 32-day experiment, pigs were sacrificed and redox potential (Eh), pH, volatile fatty acid concentration, densities of methanogens and acetogens, and expression of methyl coenzyme-M reductase subunit A gene were determined in digesta contents from the cecum, colon and rectum. Results showed that S. cerevisiae YST2 decreased (P<0.05) the average daily enteric CH4 production by 25.3%, lowered the pH value from 6.99 to 6.69 in the rectum, and increased the Eh value in cecum and colon by up to −55 mV (P<0.05). Fermentation patterns were also altered by supplementation of YST2 as reflected by the lower acetate, and higher propionate molar proportion in the cecum and colon (P<0.05), resulting in lower acetate : propionate ratio (P<0.05). Moreover, there was a 61% decrease in Methanobrevibacter species in the upper colon (P<0.05) and a 19% increase in the acetogen community in the cecum (P<0.05) of treated pigs. Results of our study concluded that supplementation of S. cerevisiae YST2 at 3 g/kg substantially decreased enteric CH4 production in pigs.
Vortex-induced vibration (VIV) is an important physical phenomenon as one design a riser or a cylindrical structure in ocean. As the riser or the cylindrical structure is adjacent to a seabed, the boundary effect on VIV is not fully understood yet. The direct-forcing immersed boundary (DFIB) method is used to investigate a two-degree-of-freedom VIV of a flexible supported circular cylinder adjacent to a plane boundary in this study. Furthermore, the effect of the VIV of cylinder on skin friction of the plane boundary is investigated. The effects of varying reduced velocity and gap ratio on VIV are discussed. Only a single vortex street is found when the cylinder is close to plane boundary. Hydrodynamic coefficients of the freely vibrating cylinder are analyzed in time and spectral domains. Furthermore, nearly round oval-shaped motion is observed as the so-called lock-in phenomenon occurs. The skin friction of the plane boundary is predicted by the DFIB model. Results show that the vibrating cylinder in the boundary layer flow can reduce the friction effectively. This proposed DFIB model can be useful for the investigation of VIV of the structures under the plane boundary effect even for a small gap between the cylinder and the boundary.
In recent years, the material Au-20Sn eutectic solder, which is resistant to high temperatures, is used for electric interconnections in high-power modules, the material properties such as temperature and strain rate dependent stress-strain curve are critically needed for reliability assessment of Au-20Sn solder joint. Thus, this study was performed to determine the material properties of Au-20Sn eutectic solder under various strain rates and temperature loads. Many researches using shear test to determine the shear resistance of solder joint, however, the mechanical strength as measured by the shear test is the maximum shear strength of the package joint, but this measurement does not represent the stress-strain behavior of Au-20Sn material. To identify the material properties of Au-20Sn eutectic solder, the tensile test was performed to measure its mechanical strength and nonlinear material properties. The strain rate effect was examined in terms of the influence of the mechanical strength on the Au-20Sn eutectic solder at different tensile rates. The temperature-dependent material properties of Au-20Sn solder were also measured under various thermal loadings, and material properties of Au-20Sn obtained in this research can be applied to the simulation model, the thermomechanical behavior and reliability of the power module can be further analyzed and evaluated.
The Weibel instability of the collimated MeV fast electron beams in a nanotube array target is researched in this work. It is found that the filamentation of the fast electrons is significantly suppressed. When fast electrons propagate the nanotube array, a strong magnetic field is created near the surface of tubes to obstruct the transverse movement of the fast electrons and bend them into the inner vacuum spaces between the successive tubes. In consequence, the positive feedback loop between the magnetic field perturbation and the electrons density perturbation is broken and the Weibel instability is thus weakened. Furthermore, the calculated results by a hybrid particle-in-cell code have also proven this weakening effect on the Weibel instability. Because of the high-energy density delivered by the MeV electrons, these results indicate some significant applications in the high-energy physics, such as radiography, fast-electron beam focusing, and perhaps fast ignition.
To examine the incidence of asthma in adult patients with major depressive disorder (MDD).
From the National Health Insurance database of Taiwan, we identified 30 169 adult patients who were newly diagnosed with MDD between 2000 and 2010. Individuals without depression were randomly selected four times and frequency matched for sex, age and year of diagnosis. Both cohorts were followed-up for the occurrence of asthma up to the end of 2011. Adjusted hazard ratios (aHRs) of asthma were estimated using the Cox proportional hazards method.
The overall incidence of asthma was 1.91-fold higher in the MDD cohort than in the non-depression cohort (7.55 v. 3.96 per 1000 person-years), with an aHR of 1.66 (95% confidence interval (CI) 1.55–1.78). In both cohorts, the incidence of asthma was higher in patients and controls who were female, aged, with comorbidities and users of aspirin or beta-adrenergic receptor blockers. No significant difference was observed in the occurrence of asthma between patients with MDD treated with selective serotonin reuptake inhibitors (SSRIs) and those treated with non-SSRIs (SSRIs to non-SSRIs aHR = 1.03, 95% CI 0.91–1.17).
Adult patients with MDD are at a higher risk of asthma than those without depression are.
It remains unclear whether the topological deficits of the white matter network documented in cross-sectional studies of chronic schizophrenia patients are due to chronic illness or to other factors such as antipsychotic treatment effects. To answer this question, we evaluated the white matter network in medication-naive first-episode schizophrenia patients (FESP) before and after a course of treatment.
We performed a longitudinal diffusion tensor imaging study in 42 drug-naive FESP at baseline and then after 8 weeks of risperidone monotherapy, and compared them with 38 healthy volunteers. Graph theory was utilized to calculate the topological characteristics of brain anatomical network. Patients’ clinical state was evaluated using the Positive and Negative Syndrome Scale (PANSS) before and after treatment.
Pretreatment, patients had relatively intact overall topological organizations, and deficient nodal topological properties primarily in prefrontal gyrus and limbic system components such as the bilateral anterior and posterior cingulate. Treatment with risperidone normalized topological parameters in the limbic system, and the enhancement positively correlated with the reduction in PANSS-positive symptoms. Prefrontal topological impairments persisted following treatment and negative symptoms did not improve.
During the early phase of antipsychotic medication treatment there are region-specific alterations in white matter topological measures. Limbic white matter topological dysfunction improves with positive symptom reduction. Prefrontal deficits and negative symptoms are unresponsive to medication intervention, and prefrontal deficits are potential trait biomarkers and targets for negative symptom treatment development.
Background: Disease-modifying therapies (DMT) have been shown to reduce relapses and delay disability in individuals with relapsing-remitting multiple sclerosis (MS). However, these medications can cause adverse events (AE) leading to poor adherence. To better understand their clinical utility, this study examined real-life experiences with DMT in a tertiary MS clinic. Methods: A retrospective chart review (1999-2015) was conducted to evaluate the prevalence of AE and discontinuation rates of Health Canada approved DMT. Results: 445 MS patients who have used at least one DMT in their lifetime were reviewed. Among first-line injectable therapies, interferon beta (IFNβ) 1-α IM users (49.6%) were most likely to report an AE. Flu-like reactions and injection site reactions were the most commonly reported AE. Among first-line oral therapies, BG-12 users (58.5%) were most likely to report an AE. The most common AE were flushing and gastrointestinal upset. DMT that were most frequently discontinued as a result of AE were IFNβ 1-α SC (39.3%), IFNβ 1-α IM (36.8%) and BG-12 (34.6%). Conclusions: The prevalence of AE and discontinuation rate were congruent. In comparison with recent literature, this study demonstrated lower prevalence of AE but equivocal or higher discontinuation rates. This discrepancy could represent a more realistic depiction of the impact that DMT AE have on patients.
Post-irradiation rhinosinusitis is one of the most common untoward side effects in patients with nasopharyngeal carcinoma. This study aimed to evaluate the effect of fluticasone propionate aqueous nasal spray on post-irradiation rhinosinusitis.
Nasopharyngeal carcinoma patients who had undergone radiotherapy and subsequently developed chronic rhinosinusitis were randomised to receive either fluticasone propionate aqueous nasal spray 200 µg plus nasal irrigation or a single nasal irrigation, for six months. A questionnaire, nasal endoscopy and computed tomography were used to evaluate rhinosinusitis severity, at the beginning of treatment, and at three and six months after treatment.
The group who received fluticasone propionate aqueous nasal spray combined with irrigation had fewer nasal complaints (overall symptoms, blocked nose and headache were reduced), a better quality of life and less severe endoscopic findings than those who only received nasal irrigation at three and six months after treatment.
Nasal steroids are a safe and effective therapy for patients with post-irradiation rhinosinusitis.
Hepatitis C virus (HCV) has become a global public health problem. Many studies have been conducted to identify risk factors for HCV infection. However, some of these studies reported inconsistent results. Using data collected from 11 methadone clinics, we fit both a non-spatial logistical regression and a geographically weighted logistic regression to analyse the association between HCV infection and some factors at the individual level. This study enrolled 5401 patients with 30·0% HCV infection prevalence. The non-spatial logistical regression found that injection history, drug rehabilitation history and senior high-school education or above were related to HCV infection; and being married was negatively associated with HCV infection. Using the spatial model, we found that Yi ethnicity was negatively related to HCV infection in 62·0% of townships, and being married was negatively associated with HCV infection in 81·0% of townships. Senior high-school education or above was positively associated with HCV infection in 55·2% of townships of the Yi Autonomous Prefecture. The spatial model offers better understanding of the geographical variations of the risk factors associated with HCV infection. The geographical variations may be useful for customizing intervention strategies for local regions for more efficient allocation of limited resources to control transmission of HCV.
This paper describes an experimental investigation of steady-state resonant waves. Several co-propagating short-crested wave trains are generated in a basin at the State Key Laboratory of Ocean Engineering (SKLOE) in Shanghai, and the wavefields are measured and analysed both along and normal to the direction of propagation. These steady-state resonant waves are first calculated theoretically under the exact resonance criterion with sufficiently high nonlinearity, and then are generated in the basin by means of the main wave components that contain at least 95 % of the wave energy. The steady-state wave spectra are quantitatively observed within the inherent system error of the basin and identified by means of a contrasting experiment. Both symmetrical and anti-symmetrical steady-state resonant waves are observed and the experimental and theoretical results show excellent agreement. These results offer the first experimental evidence of the existence of steady-state resonant waves with multiple solutions.
Dengue, one of the most important mosquito-borne diseases, is a major international public health concern. This study aimed to assess potential dengue infection risk from Aedes aegypti in Kaohsiung and the implications for vector control. Here we investigated the impact of dengue transmission on human infection risk using a well-established dengue–mosquito–human transmission dynamics model. A basic reproduction number (R0)-based probabilistic risk model was also developed to estimate dengue infection risk. Our findings confirm that the effect of biting rate plays a crucial role in shaping R0 estimates. We demonstrated that there was 50% risk probability for increased dengue incidence rates exceeding 0·5–0·8 wk−1 for temperatures ranging from 26°C to 32°C. We further demonstrated that the weekly increased dengue incidence rate can be decreased to zero if vector control efficiencies reach 30–80% at temperatures of 19–32°C. We conclude that our analysis on dengue infection risk and control implications in Kaohsiung provide crucial information for policy-making on disease control.