99 research outputs found
Analisis Hidrolika Bangunan Krib Permeabel pada Saluran Tanah (Uji Model Laboratorium)
One of the structures to protect river bank erosion is groyne. Groyne can serve and control water flow, reducing flow velocity and scour of river bank. The purposes of this study is to analyze the changes in the river bed elevation (morphology) and the depth of scour in the upstream groyne caused by the permeable groyne installed at the river meanders. The experiment was conducted at Fluid Mechanics and Hydraulics Laboratory, Sriwijaya University. The study tested the hydraulics models, a trapezoidal channel, meanders angle of 90˚, five permeable groynes at meanders, and the water flowing in the channels was clear water. The observations were carried out with a flow rate was 63,32 Lt / min, three variations of permeable groynes angle were 45˚, 90˚ and 135˚ to the upstream within 1 hour, 2,5 hours and 4 hours for each angle variations . The results of this study showed that the flow velocity of meanders was decreasing to the end of the meanders, and the changes of channel only occurred at the riverbed. Maximum riverbed changes (Bt / Bo) for permeable groyne angle of 45˚, 90˚ and 135 ˚ were 1,376 cm, 1,346 cm dan 1,452 cm. The maximum depth of scour (ds/y) for permeable groyne angle of 45˚, 90˚ and 135˚ were 1,05 cm, 0,95 cm dan 1,17 cm. Thus, permeable groyne with angle of 90 proved to be the best with the smallest riverbed changes (Bt /Bo) was 1,346 cm and the coefficient of determination (R2) was 0,9384, and also the smallest scour depth (ds/y) was 0,95 cm and the coefficient of determination (R2) was 0,8317 compared to other groyne permeable angles
When a Factor is Measured with Error: The Role of Conditional Heteroskedasticity in Identifying and Estimating Linear Factor Models
AIDS Vaccine for Asia Network (AVAN): Expanding the Regional Role in Developing HIV Vaccines
Yiming Shao and colleagues describe the work of AVAN, the AIDS Vaccine for Asia Network, which aims to strengthen its regional efforts in finding an AIDS vaccine
Broad and narrow personality traits as markers of one-time and repeated suicide attempts: A population-based study
<p>Abstract</p> <p>Background</p> <p>Studying personality traits with the potential to differentiate between individuals engaging in suicide attempts of different degrees of severity could help us to understand the processes underlying the link of personality and nonfatal suicidal behaviours and to identify at-risk groups. One approach may be to examine whether narrow, i.e., lower-order personality traits may be more useful than their underlying, broad personality trait dimensions.</p> <p>Methods</p> <p>We investigated qualitative and quantitative differences in broad and narrow personality traits between one-time and repeated suicide attempters in a longitudinal, population-based sample of young French Canadian adults using two multivariate regression models.</p> <p>Results</p> <p>One broad (Compulsivity: OR = 2.0; 95% CI 1.2–3.5) and one narrow personality trait (anxiousness: OR = 1.1; 95% CI 1.01–1.1) differentiated between individuals with histories of repeated and one-time suicide attempts. Affective instability [(OR = 1.1; 95% CI 1.04–1.1)] and anxiousness [(OR = .92; 95% CI .88–.95)], on the other hand, differentiated between nonattempters and one-time suicide attempters.</p> <p>Conclusion</p> <p>Emotional and cognitive dysregulation and associated behavioural manifestations may be associated with suicide attempts of different severity. While findings associated with narrow traits may be easier to interpret and link to existing sociobiological theories, larger effect sizes associated with broad traits such as Compulsivity may be better suited to objectives with a more clinical focus.</p
Intra-abdominal candidiasis: The importance of early source control and antifungal treatment
Intra-abdominal candidiasis (IAC) is poorly understood compared to candidemia. We described the clinical characteristics, microbiology, treatment and outcomes of IAC, and identified risk factors for mortality. We performed a retrospective study of adults diagnosed with IAC at our center in 2012-2013. Risk factors for mortality were evaluated using multi-variable logistic regression. We identified 163 patients with IAC, compared to 161 with candidemia. Types of IAC were intra-abdominal abscesses (55%), secondary peritonitis (33%), primary peritonitis (5%), infected pancreatic necrosis (5%), and cholecystitis/cholangitis (3%). Eighty-three percent and 66% of secondary peritonitis and abscesses, respectively, stemmed from gastrointestinal (GI) tract sources. C. albicans (56%) and C. glabrata (24%) were the most common species. Bacterial co-infections and candidemia occurred in 67% and 6% of patients, respectively. Seventy-two percent of patients underwent an early source control intervention (within 5 days) and 72% received early antifungal treatment. 100-day mortality was 28%, and highest with primary (88%) or secondary (40%) peritonitis. Younger age, abscesses and early source control were independent predictors of survival. Younger age, abscesses and early antifungal treatment were independently associated with survival for IAC stemming from GI tract sources. Infectious diseases (ID) consultations were obtained in only 48% of patients. Consulted patients were significantly more likely to receive antifungal treatment. IAC is a common disease associated with heterogeneous manifestations, which result in poor outcomes. All patients should undergo source control interventions and receive antifungal treatment promptly. It is important for the ID community to become more engaged in treating IAC
Drought analysis and water resource availability using standardised precipitation evapotranspiration index
Trend analysis for potential evapotranspiration (PET) and climatic water balance (CWB) is critical in identifying the wetness or dryness episodes with respect to the water surplus or deficit. The PET is computed based on the monthly average temperature for the entire Peninsular Malaysia using Thornthwaite parameterization. The trends and slope's magnitude for the PET and CWB were then investigated using Mann-Kendall, Spearman's rho tests and Thiel-Sen estimator. The 1-, 3-, 6- and 12-month standardised precipitation evapotranspiration index (SPEI) is applied to determine the drought episodes and the average recurrence interval are calculated based on the SPEI. The results indicate that most of the stations show an upward trend in annual and monthly PET while majority of the regions show an upward trend in annual CWB except for the Pahang state. The increasing trends detected in the CWB describe water is in excess especially during the northeast monsoons while the decreasing trends imply water insufficiency. The excess water is observed mostly in January especially in the west coast, east coast and southwest regions that suggest more water is available for crop requirement. The average recurrence interval for drought episodes is almost the same for the smaller severity with various time scale of SPEI and high probability of drought occurrence is observed for some regions. The findings are useful for policymakers and practitioners to improve water resources planning and management, in particular to minimise drought effects in the future. Future research shall address the influence of topography on drought behaviour using more meteorological stations and to include east Malaysia in the analysis
Bivariate copula in Johor rainfall data
Copula is a probability distribution that allows a joint distribution function build from different univariate marginal distribution function. The climate in Malaysia is very humid, which cause the rainfall data is usually skewed. Gumbel, Clayton and skew t copula are distributions that good in analyze data that is extreme. Five rain gauge stations in Johor will be used in this study. The most suitable copula function that best suit the bivariate relation among the five stations will be studied. The Akaike information criterion and Bayesian information criterion will be the used as the moderators to decide the best suit copula function. Gumbel copula is the best suit copula function among the five rain gauge stations
- …