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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.
The detection and monitoring of meltwater within firn presents a significant monitoring challenge. We explore the potential of small wireless sensors (ETracer+, ET+) to measure temperature, pressure, electrical conductivity and thus the presence or absence of meltwater within firn, through tests in the dry snow zone at the East Greenland Ice Core Project site. The tested sensor platforms are small, robust and low cost, and communicate data via a VHF radio link to surface receivers. The sensors were deployed in low-temperature firn at the centre and shear margins of an ice stream for 4 weeks, and a ‘bucket experiment’ was used to test the detection of water within otherwise dry firn. The tests showed the ET+ could log subsurface temperatures and transmit the recorded data through up to 150 m dry firn. Two VHF receivers were tested: an autonomous phase-sensitive radio-echo sounder (ApRES) and a WinRadio. The ApRES can combine high-resolution imaging of the firn layers (by radio-echo sounding) with in situ measurements from the sensors, to build up a high spatial and temporal resolution picture of the subsurface. These results indicate that wireless sensors have great potential for long-term monitoring of firn processes.
The phase-sensitive radio-echo sounder (pRES) is a powerful new instrument that can measure the depth of internal layers and the glacier bed to millimetre accuracy. We use a stationary 16-antenna pRES array on Store Glacier in West Greenland to measure the three-dimensional orientation of dipping internal reflectors, extending the capabilities of pRES beyond conventional depth sounding. This novel technique portrays the effectiveness of pRES in deriving the orientation of dipping internal layers that may complement profiles obtained through other geophysical surveying methods. Deriving ice vertical strain rates from changes in layer depth as measured by a sequence of pRES observations assumes that the internal reflections come from vertically beneath the antenna. By revealing the orientation of internal reflectors and the potential deviation from nadir of their associated reflections, the use of an antenna array can correct this assumption. While the array configuration was able to resolve the geometry of englacial layers, the same configuration could not be used to accurately image the glacier bed. Here, we use simulations of the performance of different array geometries to identify configurations that can be tailored to study different types of basal geometry for future deployments.
Compulsory admission can be experienced as devaluing and stigmatising by people with mental illness. Emotional reactions to involuntary hospitalisation and stigma-related stress may affect recovery, but longitudinal data are lacking. We, therefore, examined the impact of stigma-related emotional reactions and stigma stress on recovery over a 2-year period.
Shame and self-contempt as emotional reactions to involuntary hospitalisation, stigma stress, self-stigma and empowerment, as well as recovery were assessed among 186 individuals with serious mental illness and a history of recent involuntary hospitalisation.
More shame, self-contempt and stigma stress at baseline were correlated with increased self-stigma and reduced empowerment after 1 year. More stigma stress at baseline was associated with poor recovery after 2 years. In a longitudinal path analysis more stigma stress at baseline predicted poorer recovery after 2 years, mediated by decreased empowerment after 1 year, controlling for age, gender, symptoms and recovery at baseline.
Stigma stress may have a lasting detrimental effect on recovery among people with mental illness and a history of involuntary hospitalisation. Anti-stigma interventions that reduce stigma stress and programs that enhance empowerment could improve recovery. Future research should test the effect of such interventions on recovery.
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.
There is a need for interventions that effectively reduce compulsory admission to psychiatry. We conducted a randomised controlled trial to investigate whether an innovative intervention programme prevents compulsory re-admission in people with serious mental illness.
The programme addresses primarily patients’ self-management skills. It consists of individualised psychoeducation focusing on behaviours prior to and during illness-related crises, crisis cards and, after discharge from the psychiatric hospital, a 24-month preventive monitoring. A total of 238 inpatients with compulsory admission(s) in the past were randomised to the intervention group or to treatment as usual (TAU).
Fewer participants who completed the 24-month programme were compulsorily readmitted to psychiatry (28%), compared with those receiving TAU (43%). Likewise, the number of compulsory readmissions per patient was significantly lower (0.6 v. 1.0) and involuntary episodes were shorter (15 v. 31 days), compared with TAU. A negative binomial regression model showed a significant intervention effect (RR 0.6; 95% confidence interval 0.3–0.9); further factors linked to the risk of compulsory readmission were the number of compulsory admissions in the patient's history (RR 2.8), the diagnosis of a personality disorder (RR 2.8), or a psychotic disorder (RR 1.9). Dropouts (37% intervention group; 22% TAU) were characterised by a high number of compulsory admissions prior to the trial, younger age and foreign nationality.
This study suggests that this intervention is a feasible and valuable option to prevent compulsory re-hospitalisation in a high-risk group of people with severe mental health problems, social disabilities, and a history of hospitalisations.
The musk deer (Moschus berezovskii) is an economically important species from which musk is extracted and used in perfumes and medicines. Cestodes (parasitic flatworms) of the genus Moniezia are important parasites that infect this endangered species and can cause high mortality in young deer. In 1982, Moniezia (S.) sichuanensis sp. nov. was described from a specimen obtained from wild musk deer. The new species was distinct from the other described species of Moniezia by the sawtooth-shaped interproglottidal glands, the thick vagina and the absence of a cirrus spine. In the present study, 12 cestodes collected from musk deer were examined morphologically and confirmed to be M. sichuanensis. Molecular characterization was performed by amplifying and comparing the internal transcribed spacer 1 (ITS1) and 5.8S rRNA gene (ITS1–5.8S) of ribosomal DNA with available sequences from other Moniezia species. The amplified sequences ranged from 761 to 764 bp and similarity ranged from 98.7–100%, compared to 67.8–92.4% with other Moniezia spp. Construction of a phylogenetic tree using the neighbour-joining method indicated that all 12 ITS1–5.8S sequences formed a single clade, confirming M. sichuanensis as a separate species. This study provides novel molecular insight into M. sichuanensis that could prove useful for future diagnosis and control of monieziasis in musk deer.
The ApRES (autonomous phase-sensitive radio-echo sounder) instrument is a robust, lightweight and relatively inexpensive radar that has been designed to allow long-term, unattended monitoring of ice-shelf and ice-sheet thinning. We describe the instrument and demonstrate its capabilities and limitations by presenting results from three trial campaigns conducted in different Antarctic settings. Two campaigns were ice sheet-based – Pine Island Glacier and Dome C – and one was conducted on the Ross Ice Shelf. The ice-shelf site demonstrates the ability of the instrument to collect a time series of basal melt rates; the two grounded ice applications show the potential to recover profiles of vertical strain rate and also demonstrate some of the limitations of the present system.
A compact hybrid rocket motor design that incorporates a dual-vortical-flow (DVF) concept is proposed. The oxidizer (nitrous oxide, N2O) is injected circumferentially into various sections of the rocket motor, which are sectored by several solid fuel “rings” (made of hydroxyl-terminated polybutadiene, HTPB) that are installed along the central axis of the motor. The proposed configuration not only increases the residence time of the oxidizer flow, it also implies an inherent “roll control” capability of the motor. Based on a DVF motor geometry with a designed thrust level of 11.6 kN, the characteristics of the turbulent reacting flow within the motor and its rocket performance were analyzed with a comprehensive numerical model that implements both real-fluid properties and finite-rate chemistry. Data indicate that the vacuum specific impulse (Isp) of the DVF motor could reach 278 s. The result from a preliminary ground test of a lab-scale DVF hybrid rocket motor (with a designed thrust level of 3,000 N) also shows promising performance. The proposed DVF concept is expected to partly resolve the issue of scalability, which remains challenging for hybrid rocket motors development.
Autism spectrum disorder (ASD) is a highly heritable neurodevelopmental disorder, yet the search for definite genetic etiologies remains elusive. Delineating ASD endophenotypes can boost the statistical power to identify the genetic etiologies and pathophysiology of ASD. We aimed to test for endophenotypes of neuroanatomy and associated intrinsic functional connectivity (iFC) via contrasting male youth with ASD, their unaffected brothers and typically developing (TD) males.
The 94 participants (aged 9–19 years) – 20 male youth with ASD, 20 unaffected brothers and 54 TD males – received clinical assessments, and undertook structural and resting-state functional magnetic resonance imaging scans. Voxel-based morphometry was performed to obtain regional gray and white matter volumes. A seed-based approach, with seeds defined by the regions demonstrating atypical neuroanatomy shared by youth with ASD and unaffected brothers, was implemented to derive iFC. General linear models were used to compare brain structures and iFC among the three groups. Assessment of familiality was investigated by permutation tests for variance of the within-family pair difference.
We found that atypical gray matter volume in the mid-cingulate cortex was shared between male youth with ASD and their unaffected brothers as compared with TD males. Moreover, reduced iFC between the mid-cingulate cortex and the right inferior frontal gyrus, and increased iFC between the mid-cingulate cortex and bilateral middle occipital gyrus were the shared features of male ASD youth and unaffected brothers.
Atypical neuroanatomy and iFC surrounding the mid-cingulate cortex may be a potential endophenotypic marker for ASD in males.
An infant with residual severe mitral regurgitation following mitral commissurotomy developed cardiogenic unilateral pulmonary oedema and subsegmental atelectasis that resolved with mechanical mitral valve replacement.
Life satisfaction is an important indicator of wellbeing and successful ageing, while boosting life satisfaction in later life has long been a policy and service challenge. Based on a questionnaire survey with 415 Chinese older adults aged 60 years and over in Hong Kong, this study examined how older adults' travel motivations influenced their travel actions and how the travel affected their life satisfaction using structural equation modelling. A proposed ‘travel motivation–action–life satisfaction’ model showed an acceptable fit with the data. It was found that travel motivations stimulated older adults' travel actions, while their travels further contributed to greater life satisfaction. The findings of this study indicated the need for improved knowledge and understanding of older adults' travel preferences and requirements, and highlight the importance of enhancing awareness among professionals and service providers about the benefit of travelling in enhancing life satisfaction of older adults.
With good combustion characteristics, hydrogen has been developing as a clean alternative fuel of engines. This study is to develop a diesel/hydrogen dual fuel engine. The hydrogen was added at inlet port in a 4-cylinder direct injection turbocharged diesel engine with an EGR (Exhaust Gas Recirculation) system to investigate engine performance and exhaust pollutant. The measured items are composed of the gas pressure of cylinder, crank angle, consumption rate of diesel, consumption rate of hydrogen, air flow rate, emissions (HC, CO2, NOX, and Smoke), and so on. The authors analyze how the addition of hydrogen with EGR system influences the engine performance and emissions. The diesel/hydrogen dual fuel turbocharged engine can increase the brake thermal efficiency with a greater decrease in emissions compared with the turbocharged diesel engine. Furthermore, the authors little altered the engine structure to get the positive effect of energy saving and pollutant decreasing.
In long-term care facilities (LTCFs), the elderly are apt to be infected because those with latent tuberculosis infections (LTBIs) are at an increased risk for reactivation and post-primary TB disease. We report an outbreak of TB in staff and residents in a LTCF. An outbreak investigation was conducted after two TB cases were reported from the LTCF. A tuberculin skin test (TST), bacteriological examination and chest radiograph were administered to all facility staff and residents. An outbreak is defined as at least two epidemiologically linked cases that have identical Mycobacterium tuberculosis genotype isolates. This outbreak infected eight residents and one staff member, who were confirmed to have TB in a LTCF between September 2011 and October 2012. Based on the Becker method, the latent and infectious periods were estimated at 223·6 and 55·9 days. Two initial TST-negative resident contacts were diagnosed as TB cases through comprehensive TB screening. Observing elderly people who have a negative TST after TB screening appears to be necessary, given the long latent period for controlling a TB outbreak in a LTCF. It is important to consider providing LTBI treatment for elderly contacts.
Solar wind protons impinging on interplanetary dust grains are trapped, deionized, and subsequently desorbed. The steady state distribution of desorbed neutral hydrogen inside of 0.4 AU can be deduced by observation of resonantly scattered solar 121.6 nm radiation. Calculated integral intensities and spectral profiles are given, showing the clear spectral separation of the different radiation components. Given a specific solar wind proton flux, the interplanetary dust distribution can be determined. Conversely, dust density profiles from zodiacal light measurements can be used to deduce solar wind proton fluxes at heliocentric distances of 0.4 to 0.15 AU. Observations of latitudinal and short-term temporal proton flux variations seem feasible.
A numerical scheme based on the immersed interface method (IIM) is developed to simulate the dynamics of an axisymmetric viscous drop under an electric field. In this work, the IIM is used to solve both the fluid velocity field and the electric potential field. Detailed numerical studies on the numerical scheme show a second-order convergence. Moreover, our numerical scheme is validated by the good agreement with previous analytical models, and numerical results from the boundary integral simulations. Our method can be extended to Navier-Stokes fluid flow with nonlinear inertia effects.
Hypoplastic left heart syndrome is the most expensive birth defect managed in the United States, with a 5-year survival rate below 70%. Increasing evidence suggests that hospital volumes are inversely associated with mortality for infants with single ventricles undergoing stage 1 surgical palliation. Our aim was to examine the relative effects of surgeon and institutional volumes on outcomes and resource utilisation for these children.
A retrospective study was conducted using the Pediatric Health Information System database to examine the effects of the number of procedures performed per surgeon and per centre on mortality, costs, and post-operative length of stay for infants undergoing Risk Adjustment for Congenital Heart Surgery risk category six operations at tertiary-care paediatric hospitals, from 1 January, 2004 to 31 December, 2013. Multivariable modelling was used, adjusting for patient and institutional characteristics. Gaussian kernel densities were constructed to show the relative distributions of the effects of individual institutions and surgeons, before and after adjusting for the number of cases performed.
A total of 2880 infants from 35 institutions met the inclusion criteria. Mortality was 15.0%. Median post-operative length of stay was 24 days (IQR 14–41). Median standardized inpatient hospital costs were $156,000 (IQR $108,000–$248,000) in 2013 dollars. In the multivariable analyses, higher institutional volume was inversely associated with mortality (p=0.001), post-operative length of stay (p=0.004), and costs (p=0.001). Surgeon volume was associated with none of the measured outcomes. Neither institutional nor surgeon volumes explained much of the wide variation in outcomes and resource utilization observed between institutions and between surgeons.
Increased institutional – but not surgeon – volumes are associated with reduced mortality, post-operative length of stay, and costs for infants undergoing stage 1 palliation.
Anorexia nervosa (AN) and body dysmorphic disorder (BDD) are characterized by distorted body image and are frequently co-morbid with each other, although their relationship remains little studied. While there is evidence of abnormalities in visual and visuospatial processing in both disorders, no study has directly compared the two. We used two complementary modalities – event-related potentials (ERPs) and functional magnetic resonance imaging (fMRI) – to test for abnormal activity associated with early visual signaling.
We acquired fMRI and ERP data in separate sessions from 15 unmedicated individuals in each of three groups (weight-restored AN, BDD, and healthy controls) while they viewed images of faces and houses of different spatial frequencies. We used joint independent component analyses to compare activity in visual systems.
AN and BDD groups demonstrated similar hypoactivity in early secondary visual processing regions and the dorsal visual stream when viewing low spatial frequency faces, linked to the N170 component, as well as in early secondary visual processing regions when viewing low spatial frequency houses, linked to the P100 component. Additionally, the BDD group exhibited hyperactivity in fusiform cortex when viewing high spatial frequency houses, linked to the N170 component. Greater activity in this component was associated with lower attractiveness ratings of faces.
Results provide preliminary evidence of similar abnormal spatiotemporal activation in AN and BDD for configural/holistic information for appearance- and non-appearance-related stimuli. This suggests a common phenotype of abnormal early visual system functioning, which may contribute to perceptual distortions.