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Liquid biopsies such as circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) have great potential to serve as prognostic and predictive biomarkers in urologic cancers. The possibility of using liquid biopsies for real-time noninvasive and dynamic monitoring of response to therapy has been an active area of investigation. In this brief review, we outline the evidence for the potential clinical utility of CTC and ctDNA analyses in prostate, urothelial, and renal cancers.

Concerns regarding children’s health and physical activity levels have prompted a growing interest in understanding the school mode choice decision. Walking and biking to school can help school-age children achieve recommended daily physical activity levels. The growing literature in this area has provided valuable insights but has often failed to adequately consider the influence of parents on children’s decision making. This study aims to provide additional insights by examining the school mode choice with a focus on active travel and the role of parental effects. A multinomial logit model was estimated for children’s school mode choice using the 2009 National Household Travel Survey with the add-on sample for Texas. A comprehensive set of variables, including individual and household characteristics, built and travel environment measures, and parental characteristics and attitudes, were found to be influential on the decision of active travel to school. Although the focus of this study is on children’s school mode, a model examining parent’s active travel was also estimated to provide a picture of parents and their own active travel decisions through a Poisson count regression model for the parents’ non-motorized travel frequency (weekly). Findings strongly suggested that mothers’ concerns regarding traffic conditions in the neighborhood can discourage children’s active mode use. In contrast, fathers’ work flexibility seemed to facilitate more non-motorized school travel. Similarly, many factors were important in determining non-motorized trip frequency. A flexible work environment, particularly for the mothers, was observed to increase the overall trip frequency of parents. The results from this study corroborate the findings from several earlier studies while also indicating new factors not previously identified. The work done in this study can be extended in several directions. One particularly interesting avenue of future research is to model the two decisions in a joint model to identify the causal direction while accounting for unobserved factors.

The application of antiviral coatings to masks and respirators is a potential mitigating step toward reducing viral transmission during the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) pandemic. The use of appropriate masks, social distancing, and vaccines is the immediate solution for limiting the viral spread and protecting people from this virus. N95 respirator masks are effective in filtering the virus particles, but they cannot kill or deactivate the virus. We report a possible approach to deactivating SARS-CoV-2 by applying an antimicrobial coating (Goldshield 75) to masks and respirators, rendering them suitable for repeated use. Masks coated with Goldshield 75 demonstrated continuous inactivation of the Alpha and Beta variants of the SARS-CoV-2 over a 3-day period and no loss of inactivation when stored at temperatures at 50 °C.

The growth of online shopping will likely impact rates of in-store shopping, signaling potentially significant ramifications for shopping-related vehicle travel. To better understand this relationship, we studied shoppers in Davis, California using a comprehensive survey dataset to explore the effect of personal characteristics, attitudes, perceptions, and the built environment on the frequencies of shopping online and within three distinct shopping settings. Overall, results showed that attitudes and perceptions played an important role in the shopping decision. The ordered response models of shopping frequency also revealed that the shopping motivations for each setting differed. Most notably, many of the factors influencing the frequency of shopping outside Davis had the opposite effect on shopping within Davis. Joint copula models subsequently suggested that online shopping had a complementary relationship with in-store shopping frequency, even after controlling for demographic variables and attitudes. Rather than reducing shopping travel, it appears that online shopping is associated with higher in-store shopping rates.

A prior report demonstrated an unacceptably low level of accuracy in silica analytical testing, with a general negative bias (i.e., underreporting) although other inaccuracies included false-positive results when analyzing blank filters. The possible bias may have been due to the loss of sample during shipping and or sample preparation. We report on a follow-up study that was designed to mimic the original study, but in which sources of variability were evaluated. We found no effect on silica recoveries due to shipping and confirmed the prior study results that the muffle furnace ashing process led to low overall recoveries (49-104%), depending on the adherence to the recommended preparation method. Plasma ashing recoveries ranged from 89 to 108%. Our results suggest that muffle-furnace ashing using a crucible should be restricted. More broadly, however, muffle-furnace ashing is only one source of analytical error that contributes to the relatively poor overall performance revealed by Cox et al. Whatever the case, OSHA should ensure that its proposed requirements to improve laboratory performance will actually lead to the discovery and correction of all major sources of error by participating laboratories. This is particularly important in light of OSHA's proposed reduction in the PEL and action level proposed by OSHA.

Hard-carbon materials are considered as one of the most promising anodes for the emerging sodium-ion batteries. Here, we report a low-cost, scalable waste tire-derived carbon as an anode for sodium-ion batteries (SIBs). Tire-derived carbons obtained by pyrolyzing acid-treated tire at 1100 °C, 1400 °C and 1600 °C show capacities of 179, 185 and 203 mAh g −1 , respectively, after 100 cycles at a current density of 20 mA g −1 in sodium-ion batteries with good electrochemical stability. The portion of the low-voltage plateau region in the charge-discharge curves increases as the heat-treatment temperature increases. The low-voltage plateau is beneficial to enhance the energy density of the full cell. This study provides a new pathway for inexpensive, environmentally benign and value-added waste tire-derived products towards large-scale energy storage applications.

Transit has the potential to increase an individual’s level of physical activity due to the need to walk or bike at the beginning and end of each trip. Consideration of these health benefits would allow transit proponents to better demonstrate its true costs and benefits. In light of transit’s potential health-related impacts, this study contributes to the growing discussion in the emerging field of health and transportation by providing a review of the current level of understanding and evidence related to the physical activity implications of transit use and its associated health cost benefits. Findings from the review revealed that transit use is associated with increased levels of physical activity and improved health outcomes, but the magnitude of these effects is uncertain. There were few studies that estimated the health care cost savings of transit systems, and those that did tended to be imprecise and simplistic. Objective physical activity measures and frequency-based transit measures would allow for greater consistency across studies and help more directly attribute physical activity gains to transit ridership. Additionally, research in this area would benefit from disaggregate estimation techniques and more robust health datasets that can be better linked with existing transit data.

To determine how reliably commercial laboratories measure crystalline silica concentrations corresponding to OSHA's proposed limits, 105 filters were prepared with known masses of 20, 40, and 80 μg of respirable quartz corresponding to airborne silica concentrations of 25, 50, and 100 μg/m(3) and were submitted, in a blind test, to qualified commercial laboratories over a nine month period. Under these test conditions, the reported results indicated a lack of accuracy and precision needed to reliably inform regulatory compliance decisions. This was true even for filters containing only silica, without an interfering matrix. For 36 filters loaded with 20 or more micrograms of silica, the laboratories reported non-detected levels of silica. Inter-laboratory variability in this performance test program was so high that the reported results could not be used to reliably discriminate among filters prepared to reflect 8-h exposures to respirable quartz concentrations of 25, 50 and 100 μg/m(3). Moreover, even in intra-laboratory performance, there was so much variability in the reported results that 2-fold variations in exposure concentrations could not be reliably distinguished. Part of the variability and underreporting may result from the sample preparation process. The results of this study suggest that current laboratory methods and practices cannot necessarily be depended on, with high confidence, to support proposed regulatory standards with reliable data.

Background Active travel can provide solutions to both public health and transportation sustainability issues. Switching from vehicle trips to active modes can bring traffic and safety gains, easing congestion and creating a safer, more walkable environment. Furthermore, active travel can contribute to reaching medically recommended levels of physical activity. Walking and biking to school can help school-age children achieve recommended daily physical activity levels. Similarly, parents who are physically active, whether through non-motorized utilitarian trips or trips for physical and recreational purposes, can improve their own health while influencing the decisions of their children. Methods This study analyzed the topic of children's school travel decisions and parents’ non-motorized travel frequency in order to understand the determinants of these two household-level decisions that affect the overall physical activity levels of household members. The 2009 National Household Travel Survey with the add-on sample for Texas was used for the model estimation. A multinomial logit model was estimated for the children's school mode choice, and a Poisson count regression model was estimated for the parents’ non-motorized travel frequency (weekly). Results Overall, an opportunity appears to be present for increased active school travel among children in Texas. Rates of walking and biking to school were lower in Texas than the national average. Additionally, the lower rate of walking in the morning indicates that there are children able and willing to walk to school who do so only in one direction. Findings from this research highlight the importance of parental attitudes and characteristics on the school mode choice decision, with notable differences between mothers and fathers. For example, results strongly suggested that mothers’ concerns regarding traffic conditions in the neighborhood can discourage children's active mode use. In contrast, fathers’ work flexibility seemed to facilitate more non-motorized school travel. Similarly, many factors were important in determining non-motorized trip frequency. A flexible work environment, particularly for the mothers, was observed to increase the overall trip frequency of parents. Conclusions Concerns regarding health and physical activity levels have prompted a growing interest in understanding the mode choice decisions. The results from this study corroborate the findings from several earlier studies while also indicating new factors not previously identified. The work done in this study can be extended in several directions. One particularly interesting avenue of future research is to model the two decisions in a joint model to identify the causal direction while accounting for unobserved factors.

Background Policy makers are placing an increased emphasis on reducing automobile dependency and developing transportation systems that are multimodal. To help develop strategies to increase the use of alternative modes of transportation, the Texas A&M Transportation Institute (TTI) worked with the El Paso Metropolitan Planning Organization (MPO) on a research project to develop methodologies, data, analysis, and tools that can be integrated into a regional multimodal transportation plan. This paper summarizes a component of this study that included a regional population survey. The El Paso transportation survey contributes to the field by integrating various elements from transportation research, behavioral and social sciences and public health. Methods The survey was implemented between September and October 2015, and the study area included all of El Paso County, Texas, and parts of Dona Ana and Otero Counties, New Mexico. An address-based sample was used to get a representative sample of individuals age 18+ in the metropolitan area. Several analyses (e.g. bivariate descriptive analysis and spatial analysis) were conducted to examine the behaviors or motivators for using or not using the various modes of transportation, with a particular focus on alternative modes. Results The results indicated the important role of understanding regional and population characteristics, as well as behavioral barriers and motivators, as an important first step in designing effective alternative travel programs and interventions. Several factors, including neighborhood environment variables, personal and social characteristics, and attitudes and habits work together to influence residents’ participation in alternative transportation. While the personal automobile is the current dominant travel mode in El Paso, residents see great value in extending public transportation infrastructure in the future. Improving connectivity, safety and the neighborhood environment were found to be particularly essential to encourage walking and bicycling in the region. Conclusions This study was one of the first known regional transportation surveys in the United States to incorporate several elements of health and well-being. Because costs and political constraints can derail physical interventions, policy interventions aimed at addressing personal and social barriers to alternative transportation modes can be an attractive alternative. These include educational programs, marketing and promotion, regulatory measures, and financial incentives. There are various policy measures used to encourage alternative modes of transportation and not only one correct solution. The most effective strategies tend to be customized to the specific target population, work at both the individual and community levels, and incorporate a combination of intervention methods.

Fibrous minerals are common in nature but asbestiform minerals are rare. The unique mineralogical characteristic common to all the asbestos minerals is their morphologic form (or habit of crystallization) as polyfilamentous fiber bundles. The individual fibrils within the bundles have a tendency to be very long with a narrow range of diameters and grow with their long fiber axis in parallel orientation to the bundle length. The asbestiform habit imparts to the asbestos minerals sufficient flexibility and tensile strength so that most can be woven into cloth. In the past application has focused on their ability to insulate against the transfer of heat. However, these minerals possess other properties which make them useful in many industrial applications.

The potential environmental hazards and associated public health issues related to exposure to respirable dusts from the vicinity of natural in-place asbestos deposits (commonly referred to as naturally occurring asbestos, NOA) have gained the regulatory and media spotlight in many areas around the United States, such as Libby, MT, Fairfax County, VA, and El Dorado Hills, CA, among others. NOA deposits may be present in a variety of geologic formations. It has been suggested that airborne asbestos may be released from NOA deposits, and absent appropriate engineering controls, may pose a potential health hazard if these rocks are crushed or exposed to natural weathering and erosion or to human activities that create dust. The issue that needs to be addressed at a policy level is the method of assessing exposures to elongated rock fragments ubiquitous in dust clouds in these same environments and the associated risk. Elongated rock fragments and single crystal minerals present in NOA have been construed by some as having attributes, including the health effects, of asbestos fibers. However, the Occupational Safety and Health Administration (OSHA), Mine Safety and Health Administration (MSHA), and the Consumer Products Safety Commission (CPSC) found that the scientific evidence did not support this assumption. As in many environmental fields of study, the evidence is often disputed. Regulatory policy is not uniform on the subject of rock fragments, even within single agencies. The core of the issue is whether the risk parameters associated with exposures to commercial asbestos can or should be applied to rock fragments meeting an arbitrary set of particle dimensions used for counting asbestos fibers. Inappropriate inclusion of particles or fragments results in dilution of risk and needless expenditure of resources. On the other hand, inappropriate exclusion of particles or fragments may result in increased and unnecessary risk. Some of the fastest growing counties in the United States are in areas where NOA is known to exist and therefore this issue takes on national significance. This ongoing national dilemma has raised public and business concerns. There has been continuing political and scientific debate and widespread miscommunication over perceived versus actual health risks, the validity of various analytical sampling and testing methods, the questionable necessity and escalating costs of remediation procedures, and the combined negative impact on numerous commercial and public interests. Thus, conflicting research and regulatory positions on the distinctions between and hazards of true asbestos and ordinary rock fragments is all that is presently available to the public until the differing scientific communities and government agencies arrive at a consensus on these issues. The risk assessment methodology and the analytical technology needed to support inferences drawn from existing research are available, but have not been organized and implemented in the manner needed to resolve the NOA controversy. There should exist nationally adopted and peer-reviewed NOA standards (developed jointly by the scientific community, health risk professionals, and government regulators) that establish: (1) a scientific basis for risk evaluation and assessment of NOA and rock fragments; (2) accepted analytical protocols for determining if NOA actually exists in a given area and for separating NOA from related non-asbestos rock fragments and single crystal minerals; and (3) effective public policies for managing NOA, minimizing potential hazards, and protecting public health. This article will review some of the key issues involved with the current NOA debate, propose improved analytical methodologies, describe potential solutions for dealing with NOA, and outline the benefits to be gained by creating a practical national NOA public policy.

The evaluation of asbestos fibers by transmission electron microscopy requires that particulate be deposited on a filter and that the filter be prepared for analysis in a manner that retains the spatial characteristics of the particulate as it was deposited. Occasionally, the samples are prepared by redistributing the particulate onto a second filter. While numerous reports have described the effect of the redistribution of the particulate in terms of the number of particles or the resulting size of particles, no study has attempted to model the effect of redistribution. The effect of this redistribution on particle size is evaluated here and is described using standard comminution models. The proposed model is shown to reasonably fit the observed data.

A methodology has been developed for the determination of the water–cement ratio (w/c) in hardened concrete using backscattered electron imaging (BEI) by a scanning electron microscope. The method is based on concrete sections that have been vacuum impregnated with epoxy and polished to a flat surface. During impregnation of a dried concrete specimen, epoxy fills capillary porosity, cracks, and voids. The epoxy-impregnated porosity appears dark in BEI, while other phases such as calcium silicate hydrate, unhydrated cement grain and aggregate appear as brighter phases. The backscattered intensity of the epoxy is the lowest compared to all other phases present within a concrete. By using image analysis program and setting an appropriate threshold of the gray scale the capillary porosity of the concrete can be quantified. Reproducible quantitative data is obtained for a concrete sample of unknown w/c by using a set of standardized instrument parameters such as brightness, contrast and working distance. The water–cement ratio, which is directly related to the capillary porosity, can therefore be measured. Signal production, brightness, contrast, sample preparation, and general methodology are discussed. The measured data using this method is compared with data generated by using optical fluorescence microscopy, according to Nordtest NT Build 361-1999.

The by-products of the desulfurization process in a spray drier usually contain a mixture of hannebachite (CaSO3·1/2H2O), gypsum (CaSO4·2H2O), and the finer fraction of the fly ash. This material was mixed with an additional fly ash and stabilized by adding about 3 wt% lime kiln dust (LKD). The stabilized product was used either as a structural fill or was left in the storage yard for several years. Samples extracted from these sites were analyzed using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The analytical results show the formation of thaumasite (Ca3Si(OH)6(CO3)(SO4)·12H2O), ettringite (Ca6Al2(SO4)3(OH)12·26H2O), and an intermediate phase with varying chemical composition of calcium, aluminum, silicon, and sulfur.

Lewis acid-mediated reaction of monoperoxyacetals with silyl ketene acetals (SKAs) provides an efficient approach to 3-peroxyalkanoates. Propionate SKAs react with aliphatic peroxyacetals to furnish 3-peroxy-2-methyl alkanoates with modest anti -selectivity. Although acetate and thioacetate SKAs are less reactive, the latter react with unsaturated peroxyacetals to furnish peroxyalkenoates and -alkadienoates which undergo chemoselective reduction to 3-peroxyalkenals and 3-peroxyalkadienals.

Background Policymakers and researchers are increasingly recognizing the connection between public health and transportation, but health improvements are typically framed from a physical activity or active travel perspective rather than considering broader quality of life impacts. Currently, there is an inadequate understanding of the ways in which transportation and quality of life intersect, and little is known about what metropolitan planning organizations in the United States are doing to address quality of life outcomes. This study aims to develop a framework for transportation-related quality of life which we then used to examine the extent to which quality of life is being considered in metropolitan long-range transportation planning. Methods Based on a review of the literature, a conceptual framework was developed which can aid planners and policymakers in incorporating quality of life into the transportation planning process. Long-range transportation plans were then collected for 148 of the largest metropolitan planning organizations in the United States for an aggregate content analysis. The proposed framework provided the basis for the selection of multiple quality-of-life-related search terms. 11 plans were examined in further detail to assess the context in which quality of life outcomes were referenced. Results: (Analysis Ongoing) The framework identified four domains of transportation-related quality of life: physical, mental, social, and functional well-being. Physical well-being was well-represented in the plans, typically in the context of safety, air quality/emissions, active transport, or environmental justice, but references to the other domains were scarcer. Terms explicitly referenced within federal transportation legislation planning factors such as “safety,” “accessibility,” or “mobility” appeared most frequently. Larger metropolitan planning organizations tended to reference “quality of life,” “mobility,” and “economic“ more frequently, but were less likely to mention “safety“ or “social.“ Conclusions The proposed framework indicates that quality of life is not being holistically considered in long-range transportation planning. Plans primarily targeted quality of life enhancements from a physical health perspective, but other dimensions such as mental or social well-being were rarely addressed. While several of the plans explicitly mentioned the improvement of quality of life as a key objective within their vision statements, others appeared to only address quality of life in so far as it satisfied federal requirements. Furthermore, references to improving quality of life were often vague, perhaps owing to its inconsistent interpretation. More than simply mirroring the language put forth by federal legislation, metropolitan planning organizations should actively work to achieve positive quality of life outcomes.

On October 17, 1989, an earthquake struck central, coastal California including San Francisco and the Bay Area, damaging many buildings. Because of concern over the possible exposure to asbestos in the damaged buildings, building owners/managers hired several Bay Area industrial hygiene firms to collect air samples in suspect buildings. RJ Lee Group analyzed a total of 419 air samples from 55 buildings (25 school, 3 university, 20 commercial, 5 public, and 2 residential buildings) using transmission electron microscopy and has compiled the results. The data from each building were averaged and grouped accordingly into three classifications: indoor buildings, buildings with asbestos abatement in progress at the time of the earthquake, and buildings where sampling was performed to monitor clean-up of debris. Several buildings were sampled on more than 1 day. The results indicate that asbestos levels differed little from outdoor levels, even immediately after the earthquake. Exceptions to this were samples collected in the vicinity of debris clean-up and in buildings undergoing abatement which were higher than the indoor or outdoor samples. However, these samples generally had concentrations below the AHERA clearance levels and all were well below the OSHA action limit.

Indisputable evidence of alkali-silica reaction (ASR) in field concrete depends on positive identification of alkali-silica gel, the reaction product of ASR. Experimental results are given on the unambiguous detection of gel by microscopic techniques using fractured concrete surfaces.

The concentration of airborne asbestos in buildings and its implication for the health of building occupants is a major public health issue. A total of 2892 air samples from 315 public, commercial, residential, school, and university buildings has been analyzed by transmission electron microscopy. The buildings that were surveyed were the subject of litigation related to suits alleging the general building occupants were exposed to a potential health hazard as a result of exposure to the presence of asbestos containing materials (ACM). The average concentration of all asbestos structures was 0.02 structures/ml (s/ml) and the average concentration of asbestos greater than or equal to 5 microns long was 0.00013 fibers/ml (f/ml). The concentration of asbestos was higher in schools than in other buildings. In 48% of indoor samples and 75% of outdoor samples, no asbestos fibers were detected. The observed airborne concentration in 74% of the indoor samples and 96% of the outdoor samples is below the Asbestos Hazard Emergency Response Act clearance level of 0.01 s/ml. Finally, using those fibers which could be seen optically, all indoor samples and all outdoor samples are below the Occupational Safety and Health Administration permissible exposure level of 0.1 f/ml for fibers greater than or equal to 5 microns in length. These results provide substantive verification of the findings of the U.S. Environmental Protection Agency public building study which found very low ambient concentrations of asbestos fibers in buildings with ACM, irrespective of the condition of the material in the buildings.

A total of 473 air samples from 71 schools scheduled for abatement (328 indoor static samples, 51 personal samples, and 94 outdoor samples) were analyzed by transmission electron microscopy techniques. Six measures of asbestos-in-air concentration were considered: (1) total asbestos structures per cubic centimeter: (2) chrysotile structures per cubic centimeter; (3) amphibole structures per cubic centimeter; (4) structures per cubic centimeter at least 0.5 micron long and at least five times wide; (5) structures per cubic centimeter at least 5 microns long; and (6) structures per cubic centimeter at least 5 microns long and at least 0.2 micron wide. The average concentration of chrysotile structures in indoor air samples was 0.017 structures/cm3; the average concentration of amphibole structures was 0.0015 structure/cm3. Ninety-five percent of structures found were chrysotile. The average concentrations of all structures were significantly higher indoors than outdoors (P less than 0.001). The average concentration of structures more than 5 microns long indoors was 0.00023 structure/cm3. None of the following factors were significantly correlated with asbestos concentrations in air: type of asbestos-containing materials (ACM) present, condition of ACM, accessibility of ACM to students, whether ACM were covered, air flow, or whether sweeping was noted during sample collection. In addition, asbestos-in-air concentrations were not significantly different in different types of schools (high, intermediate or elementary) or in schools constructed in different time periods. Lastly, there was no correlation between the mineral type of asbestos found in the air and the type found in samples of bulk material.