Bacteroidales as a fecal contamination indicator in fresh produce industry: A baseline measurement.

Foodborne outbreaks caused by fecal contamination of fresh produce represent a serious concern to public health and the economy. As the consumption of fresh produce increases, public health officials and organizations have pushed for improvements in food safety procedures and environmental assessments to reduce the risk of contamination. Visual inspections and the establishment of "buffer zones" between animal feeding operations and producing fields are the current best practices for environmental assessments. However, a generalized distance guideline and visual inspections may not be enough to account for all environmental risk variables. Here, we report a baseline measurement surveying the background Bacteroidales concentration, as a quantitative fecal contamination indicator, in California's Salinas Valley. We collected a total of 1632 samples from two romaine lettuce commercial fields at the time of harvesting through two seasons in a year. The quantification of Bacteroidales concentration was performed using qPCR, revealing a notably low concentration (0-2.00 copies/cm2) in the commercial fields. To further enhance the applicability of our findings, we developed a user-friendly method for real-world fecal contamination risk assessment that seamlessly integrates with industry practices. Through the generation of heatmaps that visually illustrate varying risk levels across fields, this approach can identify site-specific risks and offer fresh produce stakeholders a more comprehensive understanding of their land. We anticipate this work can encourage the use of Bacteroidales in the fresh produce industry to monitor fecal contamination and prevent future foodborne outbreaks.

Dual-Functional Electrochromic Smart Window Using WO3·H2O-rGO Nanocomposite Ink Spray-Coated on a Low-Cost Hybrid Electrode.

Electrochromic windows have gained growing interest for their ability to change their optical state in the visible and NIR ranges with minimal input power, making them energy-efficient. However, material processing costs, fabrication complexity, and poor electrochromic properties can be barriers to the widespread adoption of this technology. To address these issues, electrochromic material and fabrication processes are designed to realize their potential as a cost-effective and energy-efficient technology. In this work, an electrochromic composite material-based ink is synthesized consisting of WO3·H2O nanoplates supported on rGO (reduced graphene oxide) nanosheets (WH-rGO), wherein an optimized amount of rGO (0.05 to 0.5 wt %) is introduced for providing a higher conduction pathway for efficient charge transport without sacrificing the electrochromic performance of WO3·H2O nanoplates. The stable ink dispersion prepared in the study is deposited by spray coating on transparent conducting electrodes over large areas (25 cm2). The WH-rGO nanocomposite (0.4 wt %) results in 43% optical modulation at 700 nm, with bleaching and coloration times of 6 and 8 s, respectively. Interestingly, the device also possesses an electrochemical energy storage capability with an areal capacitance of 16.3 mF/cm2. The electrochromic composite material is successfully translated on tin doped indium oxide (ITO)-coated Al metal mesh hybrid electrodes (T = 80%, Rs = 40 Ω/□) to replace ITO. Finally, an electrochromic device of 5 × 5 cm2 is fabricated by spray-coating the ink on cost-effective ITO/Al-mesh hybrid electrodes. The device displays blue to colorless modulation with an excellent bleaching time of 0.43 s and a coloration time of 2.16 s, making it one among the fast-operating devices fabricated by complete solution processing. This work showcases the economical production of a dual-function electrochromic device, which can be a feasible option as an alternative to existing ITO-based devices in both automotive and infrastructure applications.

Water security and health risk assessment of an urban household-level drinking water and sanitation system, Punjab, India.

The water scarcity and deteriorating water quality are major issues of concern to the agrarian state of Punjab, India. The focus of the study is to assess the status of drinking water and sanitation systems of Punjab using an exhaustive dataset of 1575 drinking water samples from 433 sampling locations in 63 urban local bodies of Punjab. Water security index (WSI) indicate that out of 63 urban local bodies, 13 are categorized into good class, 31 fall under fair class, and 19 fall under poor class. The access indicator under sanitation dimension shows that Bathinda region has maximum sewerage network coverage relative to other regions, whereas ca. 50% of the ULBs in Amritsar region do not have sewerage facility. It is clearly depicted that the variation in WSI is mainly attributable to sanitation dimension (10-22.5) as variation in water supply dimension (29-35) is relatively less. Hence, emphasis on indicators and variables of sanitation dimension is required for the improvement of overall WSI. The assessment of qualitative aspects of drinking water and health risk depicts that the drinking water quality of southwest part of the state (i.e. Malwa region) is under good quality class contrary to its poor groundwater quality. Kapurthala district shows high health risk due to the presence of trace metals despite being classified into good class within water security index. The drinking water quality is better and health risks are minimal in regions where drinking water is supplied via treated surface water sources (e.g. Bathinda region). Furthermore, the results of health risk assessment correlate with M[Formula: see text]-Water Quality Index outcome owing to presence of trace metals in groundwater above permissible limits. These results will help in identification of shortcomings in water supply and sanitation infrastructure and its management in urban areas.