TSS Removal Efficiency and Permeability Degradation of Sand Filters in Permeable Pavement.

Permeable pavement is a highly effective technology in Low-Impact Development (LID) for managing stormwater runoff, which helps mitigate environmental impacts. Filters are essential components of permeable pavement systems as they prevent permeability reduction, remove pollutants, and enhance the system's overall efficiency. This research paper focuses on exploring the influence of three factors, including total suspended solids (TSS) particle size, TSS concentration, and hydraulic gradient, on the permeability degradation and TSS removal efficiency of sand filters. A series of tests were conducted using different values of these factors. The results demonstrate that these factors have an influence on permeability degradation and TSS removal efficiency (TRE). A larger TSS particle size results in higher permeability degradation and TRE than a smaller particle size. Higher TSS concentrations lead to higher permeability degradation and lower TRE. Additionally, smaller hydraulic gradients are associated with higher permeability degradation and TRE. However, the influence of TSS concentration and hydraulic gradient seems less significant than that of TSS particle size for the values of the factors considered in the tests. In summary, this study provides valuable insights into the effectiveness of sand filters in permeable pavement and identifies the main factors that influence permeability degradation and TRE.

Infertility-related stress, social support, and coping of women experiencing infertility in Vietnam.

BACKGROUND: Women with an infertility problem living in traditional and developing countries face extensive social pressure, infertility-related stress, and distress, which possibly affect their choices of coping strategies. The present study aims to investigate the impact of infertility-related stress and social support on coping of Vietnamese women who live with an infertility diagnosis. PARTICIPANTS AND PROCEDURE: A cross-sectional study was conducted with 192 women diagnosed with infertility at two hospitals in the north and central regions of Vietnam. Participants completed a questionnaire consisting of the Multidimensional Scale of Perceived Social Support, the Copenhagen Multi-centre Psychosocial Infertility coping scales and the Fertility Problem Inventory, and questions about their sociodemographic characteristics, infertility-related history, and key social relationships. Four linear regression analyses were performed on four coping strategies: active-avoidance coping (AAC), active-confronting coping (ACC), passive-avoidance coping (PAC), and meaning-based coping (MBC). RESULTS: The findings show that high infertility-related stress significantly predicted the use of avoidance coping strategies (AAC and PAC) among these women, while those with a high level of perceived social support tended to use ACC and MBC. None of the four linear regression models support the moderating role of social support in the relationship between infertility-related stress and coping styles. CONCLUSIONS: The study findings show that levels of infertility-related stress and perceived social support have a direct effect on the choice of coping strategies among Vietnamese women diagnosed with infertility. The study results have practical implications in the Vietnamese context, including: (i) the development and adaptation of evidence-based and culturally appropriate interventions and counselling strategies; and (ii) social policy advocacy to better support women diagnosed with infertility, their husbands, and both as couples.

Diagnostic value of cerebral vasospasm by transcranial doppler ultrasound in Vietnamese patients with subarachnoid hemorrhage.

OBJECTIVE: Although the application of transcranial Doppler (TCD) ultrasonography in clinical diagnosis of cerebral vasospasm is popular in clinical practice in Vietnam, available evidence of the predictive value of vasospasm on TCD in the literature was mostly reported from large institutions in developed countries. Hence, this study was conducted to evaluate the value of TCD ultrasonography in the diagnosis of vasospasm in patients with subarachnoid hemorrhage (SAH) in Vietnam. PATIENTS AND METHODS: This is a prospective observational study of all aneurysmal SAH patients consecutively admitted to a single center between 2008 and December 2011. TCD and 64-slice computed tomographic angiography (CTA) were used to cerebral vasospasm in SAH patients. RESULTS: 316 patients were analyzed (mean age = 52.97±12.27 years, 52.2% males). There were statistically significant difference rates of the cerebral vasospasm by Hunt and Hess Classification and Fisher classification (p <0.01). The proportion of the patients with cerebral vasospasm who were diagnosed exactly by TCD was 95.2%, while the proportion of the patients without cerebral vasospasm diagnosed exactly was 91.5%. TCD predictive diagnostic value was the highest, with the sensitivity of 0.95 (95% CI: 0.91-0.98), specificity of 0.91 (95% CI: 0.85-0.96), positive predictive value of 0.94 (5% CI: 0.90-0.97) and negative predictive value of 0.93 (95 CI: 0.87-0.97). Hemiplegia was the clinical symptom with the highest diagnostic value with the sensitivity of 0.34 (95% CI: 0.27-0.41), specificity of 0.92 (95% CI: 0.86-0.96), positive predictive value of 0.86 (95% CI: 0.76-0.93) and negative predictive value of 0.49 (95% CI: 0.41-0.54). CONCLUSIONS: Evidence of vasospasm diagnosis on TCD ultrasonography was found with high accuracy. Current study enables to suggest the wide application of TCD in Vietnam health facilities from central to grassroots levels instead of the CTA use.