Survival of Respiratory Viruses on Fresh Produce

In addition to enteric viruses of fecal origin, emerging zoonotic viruses such as respiratory coronaviruses and influenza viruses may potentially be transmitted via contaminated foods. The goal of this study was to determine the recovery efficiencies and the survival of two respiratory viruses, namely, adenovirus 2 (Ad2) and coronavirus 229E (CoV229E), on fresh produce in comparison to the enteric poliovirus 1 (PV1). Adenovirus was recovered with efficiencies of 56.5, 31.8, and 34.8 % from lettuce, strawberries, and raspberries, respectively. Coronavirus was recovered from lettuce with an efficiency of 19.6 % yet could not be recovered from strawberries. Poliovirus was recovered with efficiencies of 76.7 % from lettuce, but only 0.06 % from strawberries. For comparison purposes, the survival of Ad2, CoV229E, and PV1 was determined for periods up to 10 days on produce. The enteric PV1 survived better than both respiratory viruses on lettuce and strawberries, with only ≤1.03 log₁₀ reductions after 10 days of storage at 4 °C compared to CoV229E not being recovered after 4 days on lettuce and reductions of 1.97 log₁₀ and 2.38 log₁₀ of Ad2 on lettuce and strawberries, respectively, after 10 days. Nevertheless, these respiratory viruses were able to survive for at least several days on produce. There is therefore the potential for transfer to the hands and subsequently to the mucosa via rubbing the eyes or nose. In addition, some respiratory coronaviruses (e.g., severe acute respiratory syndrome coronavirus) and adenoviruses are also capable of replication in the gut and there is thus some potential for acquisition through the consumption of contaminated produce.     

The variation of risk estimates through pregnancy in second trimester maternal serum screening for Down syndrome

The variation of risk estimates in second trimester maternal serum screening for Down's syndrome has been shown to be considerable in quality control schemes, i.e. UKNEQAS. We studied the biological variation of risk estimates in 16 women through pregnancy. The maternal serum markers alpha-fetoprotein (AFP), human chorionic gonadotrophin (hCG), unconjugated estriol (uE3) and β-hCG were determined six times during late first to late second trimester, and the associated likelihood ratios for Down syndrome were calculated. The interpersonal variation of markers, as well as that of the likelihood ratio, was much greater than the intrapersonal variation. The average intrapersonal standard deviation (SD) of the triple test log likelihood ratio was 0.2291, corresponding to a central 95-percentile interval 0.36–2.81 of the likelihood ratio. The interpersonal SD of the log likelihood ratio was 0.5482, corresponding to a central 95-percentile interval 0.08–11.87 of the likelihood ratio. The large difference between the intra- and interpersonal variation makes it unlikely that biological variation through pregnancy is a major contributor to the variation of risk estimates obtained several times in the same pregnancy. Rather, improvements in analytical quality and laboratory management must be expected to result in reduced variation and, in consequence, better performance of screening. Copyright © 2002 John Wiley & Sons, Ltd.     

Itaconic Acid Grafted Starch Hydrogels as Metal Remover: Capacity,Selectivity and Adsorption Kinetics

Hydrogels were synthesized by free radical graft copolymerization of itaconic acid (IA) onto corn starch (S-g-IA). For this purpose, potassium permanganate (KMnO₄)-sodium bisulfite (NaHSO₃) was used as redox initiation system. The formation of grafted starches was confirmed by Fourier transform infrared spectroscopy, wide angle X-ray scattering, thermogravimetric analysis and scanning electron microscopy. The effect of monomer concentration, neutralization, addition of crosslinking agent, N,N-bismetilenacrilamide (MBAm), and initiator concentration on grafting efficiency and adsorption capacity of the starch hydrogels was investigated. It was demonstrated that the introduction of carboxyl and carbonyl groups promoted starch hydration and swelling. Grafting degree increased with the decrease of monomer concentration, increase of initiator concentration, grade of neutralization and the addition of MBAm without neutralization. Remarkably the resulting materials exhibited water absorption capacities between 258 and 1878% and the ability to adsorb metal ions. It was experimentally confirmed the metal uptake, obtaining the higher adsorption capacity (q _e  = 35 mg/g) for the product prepared with the pre-oxidation and lower initiator concentration. The removal capacity order was Pb²⁺>Ni²⁺>Zn²⁺>Cd²⁺. Moreover, the experimental kinetic and the equilibrium adsorption data for Ni²⁺ and Pb²⁺ were best fitted to the pseudo-second order and Freundlich isotherm models, respectively. This work describes for the first time the preparation of metal removal hydrogels based on starch and itaconic acid using the pair redox system KMnO₄/NaHSO₃, which avoids the starch hydrolysis and allows itaconic acid grafting incorporation without the requirement of more reactive comonomers.     

Organizational networks in road safety: Case studies of U.S. Vision Zero cities

Objective: Each year, more than 30,000 deaths occur on U.S. roads. Recognizing the magnitude and persistence of this public health problem, a number of U.S. cities have adopted a relatively new approach to prevention, termed Vision Zero (VZ). VZ has been adopted by more than 30?U.S. cities and calls for creating a transportation system that ensures that no road traffic crash results in death or serious injury. A core component of VZ is strong multidisciplinary and multisector stakeholder engagement, and cities adopting VZ often establish a VZ coalition to foster stakeholder collaboration. However, there is little information on the structure, development, and functioning of coalitions working to achieve VZ and on tools available to study and evaluate such coalition functioning. We sought to describe the characteristics of prominent U.S. VZ city coalitions and context surrounding VZ uptake and advancement in these cities. Moreover, we demonstrate use of network analysis as one tool for exploring the structure of interorganizational relationships in coalitions.

Methods: We conducted case studies of 4 prominent U.S. VZ city coalitions in 2017–2018. We summarized coalition members’ characteristics and responses to questions about their cities’ VZ adoption, planning, and implementation. We asked each coalition member to provide information on their contact frequency, perceived productivity, and resource sharing with every other coalition member in their city and used network analysis techniques in 2 cities to understand the structures and relationships in coalitions.

Results: Findings indicated that government agencies generally constituted the majority of coalition members and often played central roles in terms of coalition network contact, productivity, and resource flow. Other emerging similarities regarding coalition establishment and VZ implementation included the need for political support, the importance of formal plan development, and increased collaboration and cooperation among partners.

Conclusions: Organizational network analyses, enriched with coalition member interviews, can elucidate key aspects of coalition creation, attributes, and relationship structure. The case studies of leading VZ coalition networks presented here highlight the use of these tools. Ultimately, understanding associations between VZ network structures and attributes and road safety outcomes could help inform effective coalition adoption, implementation, and maintenance to optimize safety outcomes.     

Water-Quality Performance of a Constructed Stormwater Wetland for All Flow Conditions1

Wadzuk, Bridget M., Matthew Rea, Gregg Woodruff, Kelly Flynn, and Robert G. Traver, 2010. Water-Quality Performance of a Constructed Stormwater Wetland for All Flow Conditions. Journal of the American Water Resources Association (JAWRA) 46(2):385-394. DOI: 10.1111/j.1752-1688.2009.00408.x Abstract: Results from a multiyear study demonstrate that a constructed stormwater wetland (CSW) improves urban stormwater runoff quality mitigating downstream impacts. Best management practices, such as CSWs, can comprehensively treat the various scales of stormwater runoff issues. Discrete sample analysis was used to investigate the CSW effect for storm events and base-flow periods on water-quality parameters [i.e., total suspended solids, total dissolved solids, total nitrogen, phosphorous (total and reactive), chloride, heavy metals (zinc, lead, and copper), and Escherichia coli]. The primary finding was that stormwater sediment load was removed through the CSW for all flow conditions during all seasons. The mechanisms responsible for the removal of suspended solids, including slower flow velocity, longer retention times, and vegetative contact, also reduced the mass of nutrients discharged downstream throughout the year. Exceedance probabilities were used to evaluate the expected pollutant reductions of nutrients and to incorporate the effect of natural flow variation on quality. Other findings included the observation that there was no significant difference in the performance of the CSW over two-year-long periods four years apart, indicating that a CSW is effective for an extended period.     

Preliminary Evaluation of the Use of Phosphogypsum for Reef Substrate. Ii. A Study of the Effects of Phosphogypsum Exposure On Diversity and Biomass of Aquatic Organisms

The effects of cement consolidated phosphogypsum (PG) on marine organisms was investigated under natural conditions in four 1000 m² estuarine ponds. Two ponds were seeded with 160 kg of PG arranged in aggregations of blocks and two ponds received similar mass of sand/cement blocks. Meiofauna were sampled quarterly and PG did not affect total meiofauna or major taxa (nematodes and copepods) density. Abundant species of copepods either were slightly increased in ponds with PG or were inconsistently affected.

All ponds were drained after one year. Three species of macroinvertebrates and 15 species of fishes were collected. Diversity indices showed modest but inconsistent variation among ponds. Only Pond 1 (control) and Pond 4 (experimental) had similar species abundances and all ponds showed unique distributions of biomasses among species. Thus, no differences in community structure attributable to the presence of PG could be detected among benthic invertebrates, natant invertebrates, or fishes.     

Experience affects mating behavior, but does not impact parental reproductive allocation in a lizard

Investment into reproduction is influenced by multiple factors and varies substantially between males and females. Theory predicts that males should adjust their ejaculate size or quality in response to variation in female experience or phenotypic quality. In addition, sperm investment by males may also be influenced by their own status and experience. Although such adjustments of male ejaculate size can impact reproductive success (via fertilization success), fitness returns from male sperm investment may be influenced (either limited or facilitated) by the level of maternal investment. To test this hypothesis, we conducted an experiment that simultaneously evaluated the effect of paternal and maternal experience (which incorporates mating status, age, body size, and other related variables) on paternal sperm investment and maternal reproductive allocation in the lizard Anolis sagrei. During staged mating trials, experienced males were more likely to copulate with females, but these individuals were less likely to transfer sperm during mating than were naïve individuals. Maternal experience had no impact on these mating behaviors. In contrast to expectations, experience and phenotypic quality (of both sexes) had no impact on male ejaculate size or quality (proportion of live sperm) or on maternal reproductive investment (in terms of egg size and yolk steroids). These findings were intriguing given the mating system and past evidence for differential maternal investment in relation to sire quality in A. sagrei. The results found in this study highlight the complexity of reproductive investment patterns, and we urge caution when applying general conclusions across populations or taxa.     

ASSESSMENT OF METHODS FOR MEASURING EMBEDDEDNESS: APPLICATION TO SEDIMENTATION IN FLOW REGULATED STREAMS1

Abstract: Five commonly used methods for measuring embeddedness the — degree to which fine particles surround coarse substrate on the surface of the streambed — are assessed and used to evaluate the sedimentation pattern resulting from impoundment on tributaries of the Connecticut River. Results show that the U.S. Environmental Protection Agency (USEPA) method best reflects the sediment regime on these rivers. On the Ompompanoosuc River, regulated by a run-of-the-river/flood control dam, embeddedness increases significantly directly downstream of the dam. On the unregulated White River, no downstream trends in embeddedness are observed. The USEPA results on the Ompompanoosuc River reflect the movement of a local decrease in embeddedness, interpreted as a moving region of scour, with a calculated transport rate of approximately 5 to 25 m/day. Observed transport rates are similar to previously measured sediment transport rates and consistent with results from a multifraction sediment transport model. Application of the USEPA method to an additional regulated tributary demonstrates the effects of dam management on embeddedness. Flow regulation with high sediment trapping efficiency results in a decrease in embeddedness downstream of the dam. Results provide insight into the utility of available methods for evaluating the effects of management practice on streambed composition.