Urine culture doubtful in determining etiology of diffuse symptoms among elderly individuals: a cross-sectional study of 32 nursing homes

Background: The high prevalence of bacteriuria in elderly individuals makes it difficult to know if a new symptom is related to bacteria in the urine. There are different views concerning this relationship and bacteriuria often leads to antibiotic treatments. The aim of this study was to investigate the relationship between bacteria in the urine and new or increased restlessness, fatigue, confusion, aggressiveness, not being herself/himself, dysuria, urgency and fever in individuals at nursing homes for elderly when statistically considering the high prevalence of asymptomatic bacteriuria in this population.\ud \ud Methods: In this cross-sectional study symptoms were registered and voided urine specimens were collected for urinary cultures from 651 elderly individuals. Logistic regressions were performed to evaluate the statistical correlation between bacteriuria and presence of a symptom at group level. To estimate the clinical relevance of statistical correlations at group level positive and negative etiological predictive values (EPV) were calculated.\ud \ud Results: Logistic regression indicated some correlations at group level. Aside from Escherichia coli in the urine and not being herself/himself existing at least one month, but less than three months, EPV indicated no clinically useful correlation between any symptoms in this study and findings of bacteriuria.\ud \ud Conclusions: Urinary cultures provide little or no useful information when evaluating diffuse symptoms among elderly residents of nursing homes. Either common urinary tract pathogens are irrelevant, or urine culture is an inappropriate test

Numerical Simulation of Aging by Water-Trees of XPLE Insulator Used in a Single Hi-Voltage Phase of Smart Composite Power Cables for Offshore Farms

Submarine power cables are expected to last 20 years without maintenance to be considered technologically reliable enough and economically beneficial. One of the main issues facing this target is the development of what is called commonly water-trees (nanometer-sized flaws filled with residual humidity), that form within XLPE (cross-linked Polyethylene) insulators and then migrate towards copper, thus leading to its corrosion and further to possible shut-down. Water trees are resulting from the coalescence of nanovoids filled with residual humidity that migrate towards copper under the combined effects of electrical forces and plastic deformation. The nanovoids are originated during manufacturing, shipping, handling and embedding in deep seas. The formation of these nanovoids leads to the degradation of the service lifetime of submarine power cables. Current research is intended to come up with a way to go a little further towards the generalization of coalescence of n nanovoids. In the perspective of multi-physics modeling, a preliminary 3D finite element model was built. Although water voids are distributed randomly inside XLPE, in this study, two extreme cases where the voids are present parallel and perpendicular to the copper surface, were considered for simplification. This will enable checking the electric field effect on neighbouring voids, in both cases as well as the influence of the proximity of the conductor on the plasticity of voids, that further leads to their coalescence. It is worthwhile to note that assessing water-trees formation and propagation through an experimental campaign of ageing tests may extend over decades. It would therefore be an exceptional opportunity to be able to get insight into this mechanism through numerical modeling that needs a much shorter time. The premilinary model suggested is expected to be extended in the future so that to include more variables (distribution and shapes of nano-voids, water pressure, molecular modeling, electric discharge

Prevention of Perinatal HIV Transmission in an Area of High HIV Prevalence in the United States

Objective: To evaluate the uptake of perinatal HIV preventive interventions by the risk of perinatal HIV transmission in mother–infant pairs in a high–HIV prevalence area in the US. Study design: This was a retrospective cohort study of mother–infant pairs with perinatal HIV exposure during 2013-2017 managed at a subspecialty pediatric HIV program in Washington, DC. We collected demographic data, maternal HIV history, delivery mode, maternal and infant antiretroviral drug (ARV) use, and infant HIV test results. We compared the uptake of recommended preventive interventions in low-risk (ie, mothers on antiretroviral therapy [ART] with viral suppression) and high-risk (mothers without ART or viral suppression) mother–infant pairs using the Pearson chi-square, Fisher exact, and Wilcoxon rank-sum tests and logistic regression. Results: We analyzed 551 HIV-exposed infants (HEIs) and 542 mothers living with HIV. The majority of mothers received ARVs (95.5%), had HIV RNA ≤1000 copies/mL before delivery (81.9%), and received intrapartum zidovudine (ZDV; 65.5%). The majority of all HEIs were low risk (82.6%) and received postpartum ARVs (98.9%). Among the low-risk infants, 53.2% were delivered via cesarean delivery (CD), and 62.9% and 96.5% were administered intrapartum and postpartum ZDV, respectively. Among high-risk infants, 84.4% were delivered via CD, 78.1% received intrapartum ZDV, and 62.5% received combination ART. Nine high-risk infants acquired HIV perinatally. Conclusion: In an area of high HIV prevalence in the US, a large proportion of low-risk HEIs received intrapartum ZDV and were delivered via CD. We also observed missed opportunities for the prevention of perinatal HIV transmission