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Authors: Jerry John Ouner, Agani Afaya, Jaffer Okiring, Sera Young, Rachel G. A. Thompson, Torsten B. Neilands, Tarik Benmarhnia, Isaac Yeboah, Raymond Aborigo, Monica Getahun, Sheri Weiser

Although recent literature increasingly recognizes HIV, food insecurity, water insecurity, and depression as interconnected syndemics, research simultaneously evaluating the role of all these factors is limited among people living with HIV. We assessed the associations between water insecurity and food insecurity and how they relate to depression among people living with HIV in Ghana. This was a cross-sectional analysis of the baseline data of an ongoing cohort in three regions of Ghana. PHQ-9 depression scale was used, summed up to generate a depression score, which was then recoded into 4 categories of ‘none-minimal’,’mild’,’moderate’, and ‘severe’. Multivariable ordered logistic regression analysis (controlling for a priori identified confounders) was used to quantify the association between water insecurity and depression. Overall average depression score was 5.88 (SD = 4.82), with 47.1% of the participants having ‘none-minimal’ depression, 32.2% having mild, 19.9% having moderate, and only 0.8% having severe depression. In the multivariate model, depression was more prevalent among participants experiencing low (aOR = 1.96; 95% CI: 1.30–2.95) or moderate water insecurity (aOR = 2.64; 95% CI: 1.45–4.82), and moderate (aOR = 2.22; 95% CI: 1.27–3.87) or high food insecurity (aOR = 3.32; 95% CI: 2.22–4.95). Higher odds of depression were also observed among females (aOR = 1.73; 95% CI: 1.23–2.44), and those reporting moderate (aOR = 6.22; 95% CI: 1.85–20.86) or high perceived stress (aOR = 21.07; 95% CI: 6.75–65.80). Lower odds of depression was observed among widowed women (aOR = 0.61; 95% CI: 0.41–0.86). The study demonstrates that both water insecurity and food insecurity are strongly associated with depression among people living with HIV. The substantially higher odds of depression among women and those experiencing moderate to high perceived stress highlight the importance of incorporating gender-responsive and stress-focused mental health interventions into HIV care.

Source: PLOS Water. DOI: 10.1371/journal.pwat.0000546. Abstract from the publisher’s feed; HTML formatting and repeated author line removed.

Authors: Vu Quang Huy, Tran Minh The Uyen, Pham Son Minh, Van-Thuc Nguyen, Hai Nguyen Le Dang

An Artificial Neural Network (ANN) model was created to predict how injection-molded parts made from flexible mechanisms would hold up under twisting fatigue. These parts were made from three common plastics—ABS (Acrylonitrile Butadiene Styrene), PP (polypropylene), and PA6 (Polyamide 6)—strengthened with up to 30 wt.% short glass fibers. The team also looked at how many times the parts were cycled during manufacturing.To test them, the samples were twisted back and forth ±40° for 100 cycles. The study examined how the type of plastic, the amount of glass fiber, and key injection molding settings affected the results. It turned out that PA6’s ability to withstand fatigue really improved when it had more glass fiber, especially 20 wt.% or more. PA6 turned out to be the strongest material in this test, followed by ABS. PP was the most consistent but also the weakest in terms of twisting strength. The ANN model was quite successful at predicting the twisting force, with a match range (R ≈ 0.94 to 0.98) and cross validation 0.93 and 0.97. The research also pointed out specific injection molding conditions—like melt temperature, filling pressure, and packing pressure—as being particularly important for the final performance. Overall, this proposed approach offers a tool to help engineers design and make plastic flexible mechanisms more effectively.

Source: PLOS ONE. DOI: 10.1371/journal.pone.0361201. Abstract from the publisher’s feed; HTML formatting and repeated author line removed.

Authors: Pham Son Minh, Thanh Trung Do, Pham Ngoc Chuong, Hung-Son Dang

The injection molding of bridge-type compliant mechanisms is sensitive to non-uniform mold temperature because the thin flexure hinges are prone to premature solidification and incomplete filling. This study evaluates a fluid-layer-assisted mold temperature-control architecture using experimental thermography, transient thermo-fluid simulation, a representative straight-channel thermal baseline, melt-filling analysis, and displacement testing of molded HDPE mechanisms. The fluid-layer thermo-fluid model was validated against infrared measurements, yielding a mean absolute error (MAE) of 5.01 °C and a root mean square error (RMSE) of 6.44 °C across six validation points. Under the numerical benchmark condition of an 80 °C inlet temperature, a mass flow rate of 59.5 g/s, and 40 s heating, the fluid-layer architecture was predicted to increase the average cavity-surface temperature by approximately 4.0 °C and reduce the maximum longitudinal temperature difference by 28.6% relative to the straight-channel model. Independent thermography of a representative steel straight-channel insert under the same inlet-temperature and flow-rate conditions showed a lower and more non-uniform surface-temperature field than the steel fluid-layer configuration, confirming the direction of the predicted thermal advantage. Melt-filling simulations subsequently predicted incomplete filling at the thin flexure region for the straight-channel configuration and complete filling for the fluid-layer configuration; this filling comparison remains simulation-based. For HDPE blends containing 0–25 wt% recycled material, the molded mechanisms retained an approximately linear input–output displacement response over the investigated range. At an input displacement of approximately 175 µm, the mean output displacement decreased from 857 µm for virgin HDPE to 745 µm at 25 wt% recycled HDPE. The results support the fluid-layer architecture as a conventionally machinable approach for improving mold-surface thermal control, while polymer morphology, fatigue durability, and experimental straight-channel filling remain subjects for future work.

Source: PLOS ONE. DOI: 10.1371/journal.pone.0361383. Abstract from the publisher’s feed; HTML formatting and repeated author line removed.

Authors: Thanh Trung Do, Tran Minh The Uyen, Pham Son Minh

Control of mold-cavity surface temperature strongly affects filling, premature frozen-layer formation, and cycle time in thin-wall injection molding. This study evaluates an induction self-heating insert with a thin heating zone directly coupled to a cooling layer using experiments, a sequentially coupled electromagnetic-thermal model, and an Artificial Neural Network (ANN). The design space contains 25 Taguchi L25 geometries defined by T, W, and L; X and Y coordinates are added so that the ANN predicts the surface temperature field. Three cooling states are considered: No Water (NW), Stagnant Water (SW), and Flowing Water (FW). Experimental ANN targets are the mean of five repeated tests. The simulation reproduced the location of the hot zone; among four cases with reported quantitative differences, three differed by no more than about 10 °C and one showed a peak difference of about 20 °C. To prevent data leakage, all 846 points from each geometry were kept together during geometry-wise validation. The resulting R² values were 0.746, 0.653, and 0.493 for NW, SW, and FW, with Root Mean Square Error (RMSE) values of 17.03, 12.97, and 12.62 °C, respectively. The effects of T, W, and L depended on the cooling state and were not consistently monotonic. A proof-of-concept molding test showed complete filling of a Chip 2 part using Low-Density Polyethylene (LDPE); the mean spacing was 28.6 µm for a nominal 30 µm, and the mean height was 106.6 µm for a nominal 100 µm. These results show that combining insert geometry, cooling-water state, and a surrogate model can support local thermal design, delay frozen-layer formation, and improve filling in injection molding.

Source: PLOS ONE. DOI: 10.1371/journal.pone.0359849. Abstract from the publisher’s feed; HTML formatting and repeated author line removed.

Authors: Ganesh Malayath, Fei Wang, Chao Zhou, Nathaniel Huebsch

Standard cell-culture ware is mass-produced in fixed designs, whereas many tissue-engineering workflows require custom inserts, lids, chambers, or patterned substrates, especially during early-stage research and method development. Conventional fabrication methods for cell culture accessories involve injection molding and machining, which are too costly and time-consuming to implement for producing custom designs in small batches, and/or while testing the usefulness of a new design before mass production. Here, we propose polycarbonate (PC) thermoforming as a solution for creating customized transparent and autoclavable accessories. We demonstrate that optimized preheating of PC overcomes issues with bubbling during thermoforming. The use of high heat deflection temperature (HDT) resins allows these PC devices to be thermoformed off molds created by Digital Light Processing (DLP) 3D prints, enabling rapid prototyping of the PC. Using this approach, we fabricated custom PC well plate inserts, staining chambers and other custom accessories. We next validated the cytocompatibility of these devices by demonstrating culture and cardiomyocyte differentiation of human induced pluripotent stem cells (iPSC). Finally, we demonstrated the utility of thermoformed PC for creating 3D engineered tissues (cardiospheres). These results establish DLP-assisted PC thermoforming as a rapid, low-cost workflow for fabricating transparent, autoclavable, user-defined cell-culture accessories during prototyping and small-batch bioengineering applications.

Source: PLOS ONE. DOI: 10.1371/journal.pone.0361065. Abstract from the publisher’s feed; HTML formatting and repeated author line removed.

Authors: Xiaoxue Sun, Qinqin Wang, Wei Zheng

Objective To address the occupational exposure risks caused by instantaneous steam overflow when opening the top cover of hatch-type boiling disinfectors in the central sterile supply department, this study developed an interlocked centrifugal exhaust system (ICES) characterized by operational simplicity and high adaptability. Methods The ICES was assembled using a centrifugal fan, Hall effect switch, instant relay, time-delay relay, solid-state relay, and piping. The system achieved automatic start/stop of the fan based on the open‑or‑closed status of the top cover. A self-controlled design was adopted on one hatch-type boiling disinfector. Temperature was measured at the chamber edge (T1) and at the technician’s facial position (T2). Airborne particle counts were also measured at the technician’s facial position. Measurements were performed under conditions with and without the ICES enabled. Data were analyzed using the Wilcoxon signed-rank test. Results After enabling the ICES, T1 and T2 decreased by 20.89% and 31.31%, respectively. The median temperature at T2 was 21.5 °C, which was close to the ambient temperature. The reduction ratios for airborne particle counts of six different sizes at the technician’s facial position ranged from 53.09% to 67.83%. All differences between groups were statistically significant (all P < 0.001). Conclusion The ICES effectively reduces steam overflow upon the top-cover opening of hatch-type boiling disinfectors and lowers the risk of occupational injury. With advantages such as wide installation adaptability, imperceptible operation, and convenient maintenance, it provides a stable and reliable solution for the safety retrofitting of existing hatch-type boiling disinfectors.

Source: PLOS ONE. DOI: 10.1371/journal.pone.0360909. Abstract from the publisher’s feed; HTML formatting and repeated author line removed.

Authors: Joseph Wells, Joseph Waiswa, Anifa Vala, Bahtisen Golla, Grace Mwashigadi, Hawanatu Jah, Marleen Temmerman, Robin Okello, Isaac Mwaniki, Herminio Cossa, Moses Mukhanya, Esperança Sevene, Yahaya Idris, Onesmus Wanje, Angela Koech, Anna Roca, Laura Braun, Marie-Laure Volvert, Fatima Touray, Umberto D’Alessandro, Peter von Dadelszen, Wendy Graham, Hannah Blencowe, the PRECISE and PRECISE-DYAD Networks

Placenta-related complications contribute substantially to maternal and perinatal mortality globally, with the greatest burden in low- and middle-income countries (LMICs). However, the potential influence of inadequate household water, sanitation and hygiene (WASH) on these outcomes remains poorly characterised. We investigated associations between household WASH conditions and selected placenta-related complications, including pre-eclampsia, small-for-gestational-age (SGA) and stillbirth, in The Gambia, Kenya and Mozambique. This secondary analysis was nested within PRECISE (PREgnancy Care Integrating Translational Science, Everywhere), a prospective observational cohort of 5,745 unselected pregnant women. Multivariable modified Poisson regression with robust standard errors was used to assess associations between household WASH exposures and pre-eclampsia, SGA or stillbirth. Missing exposure and covariate data were low (<5%) and handled using multiple imputation. Compared with water piped into the dwelling or plot, other improved water sources (adjusted relative risk [aRR] 1.18, 95% confidence interval [CI] 1.07–1.31, p = 0.002) and unimproved water sources (aRR 1.23, 95% CI 1.00–1.50, p = 0.049) were associated with a higher risk of any selected placenta-related complication. Unimproved sanitation facilities, compared with improved facilities, were also associated with increased risk (aRR 1.15, 95% CI 1.02–1.30, p = 0.019). The findings suggest that household‑level WASH conditions may be associated with selected placenta‑related complications through both direct and indirect pathways. Water sources, whether unimproved or improved, may be contaminated, and collection, transport, and storage further increase contamination risks while adding a physical burden to water collectors. Unsafe sanitation may also increase exposure to enteric pathogens. Given the observed associations, targeted WASH interventions warrant investigation as a potential strategy to reduce placenta-related complications and improve maternal and neonatal health outcomes in LMICs. Future research should explore the mechanisms linking WASH to pre-eclampsia, SGA, stillbirth and other placenta-related complications, and assess the effect of comprehensive WASH interventions.

Source: PLOS Global Public Health. DOI: 10.1371/journal.pgph.0005004. Abstract from the publisher’s feed; HTML formatting and repeated author line removed.

Authors: Yarrow Linden, Erin Kowalsky, Kevin Zhu, Christine Fagnant-Sperati, Sandra McGunegill, Arnaldo Cumbana, Magalhães Mangamela, Rassul Nalá, Matthew C. Freeman, Karen Levy, Joe Brown, The PAASIM Study Authorship Consortium

While nearly three-quarters of the globe use safely managed drinking water services, water quality can deteriorate between the point of service provision and point of consumption due to intermittent supply and the need to store water at the household level. To test if water storage contributes to waterborne pathogen hazards, we estimated prevalence and concentration of enteric pathogens in piped and stored drinking water samples in Beira, Mozambique, using large-volume sampling methods. We assessed water sample concentrates for microbial contamination from bacterial, protozoan, viral, helminthic, antimicrobial resistance (AMR), and microbial source tracking targets with RT-qPCR using a custom TaqMan Array Card. We found that enteric pathogens, AMR targets, and human mtDNA were more prevalent in stored drinking water compared to household tap water. We also detected enteric pathogens— including Cryptosporidium, Giardia, pathogenic Escherichia coli, and rotavirus— directly from 13% (11/87) of piped sources connected to a well-managed, but intermittent, water supply system, albeit less frequently than in stored water. These findings suggest that without continuity in service delivery combined with effective filtration treatment in piped supplies and safe storage microbial contamination of drinking water at the point of use may continue to occur.

Source: PLOS Water. DOI: 10.1371/journal.pwat.0000523. Abstract from the publisher’s feed; HTML formatting and repeated author line removed.

Authors: Ting Zhang, Sheng Ye, Liang Ye, Zekai Qian

This study investigates the efficacy and safety of steam cleaning technology for the removal of surface contaminants from stone cultural relics at the Tomb of Yue Fei, a nationally protected heritage site in China. The research focuses on common pollutants including dust accumulation, surface encrustation, hydro erosion, bioerosion, and anthropogenic graffiti. An evaluation method based on infrared thermography is proposed to assess cleaning effectiveness by analyzing temperature variation (T) before and after treatment. Field experiments were conducted using a steam cleaner with controlled parameters (pressure, temperature, angle, distance, and duration), and cleaning outcomes were evaluated through visual inspection, chromatic aberration measurement, and microscopic imaging. Results demonstrate that steam cleaning effectively removes most contaminants without causing significant damage to the stone substrate. The study also provides a set of recommended steam cleaning parameters for different pollutant types on limestone surfaces. The findings validate the feasibility of using infrared thermography as a non-destructive evaluation tool for cleaning efficacy, contributing to the development of standardized protocols for the conservation of stone heritage.

Source: PLOS ONE. DOI: 10.1371/journal.pone.0359835. Abstract from the publisher’s feed; HTML formatting and repeated author line removed.

Authors: Cameron Smith, Emily M. H. Woerner, Alan Leslie, Benjamin Beale, Kelly Nichols, Shannon Dill, Sarah Hirsh, Jeff Semler, Andrew Kness, Jack Keane, Marina Costa, Julie Yang, Raul Cruz-Cano, Andrew Lazur, Rachel Rosenberg Goldstein

Over 43 million individuals in the United States use private wells for drinking water, but these wells are not regulated by the Safe Drinking Water Act. Unmaintained private wells on farms could become contaminated from pathogens from various potential sources including on-farm animal waste. Microbial contaminants in private wells could increase infectious disease risks among well users, therefore it is important to conduct well water testing and keep a well maintained system. We distributed surveys and collected water samples from private wells that supply drinking water on farms from all seven regions of Maryland. Our objective was to evaluate the presence of total coliforms and E. coli in private wells and the impact of well, geographic, and precipitation factors on the bacterial contamination risk. Eighty-four water samples were collected from 79 private wells on farms across Maryland. Samples were analyzed for total coliforms and E. coli with U.S. EPA Method 1604. Data were analyzed using Fisher’s Exact test and logistic regression. Forty-three percent (34/79) of the sampled wells were positive for total coliforms and 10% (8/79) were positive for E. coli. Total coliform presence was significantly associated with county (p = 0.02), region (p < 0.01), and well condition description (p = 0.02). E. coli presence was significantly associated with region (p < 0.01), geological province type (p < 0.01), county (p = 0.04), and wellhead cover type (p = 0.03). Based on the multivariable logistic regression, wells that were described as being in okay or fair condition had significantly lower odds of total coliforms compared to wells described as being in good or excellent condition (p = 0.03), suggesting a lack of understanding about actual well conditions. There was a significant decrease in the odds of E. coli presence as precipitation levels 14 days prior to sampling increased (p = 0.02). These results emphasize the importance of private well water testing, particularly for farmers.

Source: PLOS Water. DOI: 10.1371/journal.pwat.0000636. Abstract from the publisher’s feed; HTML formatting and repeated author line removed.

Authors: Rebecca S. Kann, Sydney Hubbard, Jedidiah Snyder, Sandy McGunegill, Bacelar Muneme, João Luis Manuel, Lance A. Waller, Rassul Nalá, Karen Levy, Matthew C. Freeman, the PAASIM Study Authorship Consortium

Diarrhea remains a leading cause of morbidity and mortality for children under five, despite reductions in its global burden in recent decades. However, climate change, and its associated meteorological conditions - heavy rainfall, temperature, flooding - has the potential to impede or reverse progress, particularly in low-income, climate-vulnerable communities. Better characterization of the impact of weather and season on drinking water quality and child health will allow us to capture the anticipated health burden associated with climate change. We characterized the associations of weather and season on infant diarrhea and household stored water quality in Beira, Mozambique. We collected data from mother-child dyads in the third trimester of pregnancy and when the infant was 3-, 6-, 9-, and 12-months old. Using modified Poisson regression mixed effects models, we evaluated associations between weather (i.e., season, heavy rainfall events, ambient temperature, and flooding) and (1) household stored water quality and (2) infant diarrhea. Rainy season (aPR: 1.49; 95% CI: [1.34, 1.67]) was associated with a higher prevalence of stored water contamination, and higher temperatures were associated with a higher prevalence of stored water contamination during the dry season only (aPR: 1.14; 95% CI: [1.03, 1.27]). Source water contamination was associated with a higher prevalence of stored water contamination during both rainy (aPR: 1.32; 95% CI: [1.11, 1.56]) and dry seasons (aPR: 1.56; 95% CI: [1.22, 2.00]). Rainy season (aPR: 1.18; 95% CI: [1.01, 1.38]) was associated with a higher prevalence of infant diarrhea, as was higher temperatures, though only during the dry season (aPR: 1.19; 95% CI: [1.05, 1.35]). This study highlights the importance of addressing household water contamination for reducing the burden of diarrheal disease as well as the importance of understanding the seasonal and weather-dependent variation in both water contamination and infant diarrhea.

Source: PLOS Water. DOI: 10.1371/journal.pwat.0000599. Abstract from the publisher’s feed; HTML formatting and repeated author line removed.

Authors: Xiaofen Wu, Michelle Mut, Lauren M. Walsh, Mary G. Boyle, Rinat M. Tal, Steve M. Liao, Cherie McElroy, Cynthia Rodriguez, Stephanie A. Fritz, Lori R. Holtz

Water is an important source of microbial infections for humans and contributes to the composition of the human gut bacterial microbiome. However, viral metagenomic data from household water is lacking. We collected 110 water samples from 12 homes at 5 time points, allowing us to investigate the unique characteristics and longitudinal stability of each household’s water virome, and compare across households. Households were supplied by three different utilities and samples included point of use filtered tap and direct from the tap water. We observed that household water contains a community of viruses which is dominated by bacteriophage. Water company source is the main driver of variation of household water viromes. Viral abundance of specific taxa varied by filtration status; household water viromes are remarkably stable over time. Our results indicate that household water could be an overlooked source of bacteriophage which could affect human health by impacting gut bacterial microbiome composition, modulating immunity, or being a source of antibiotic resistance and virulence loci. These findings support the importance of future studies on the impact of the household water virome on the human gut virome.

Source: PLOS Water. DOI: 10.1371/journal.pwat.0000585. Abstract from the publisher’s feed; HTML formatting and repeated author line removed.