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The dissemination of antibiotic resistance genes (ARGs) in the environment contributes to the global rise in antibiotic resistant infections. Therefore, it is of importance to further research the exposure pathways of these emerging contaminants to humans. This study explores commercially available garden products containing animal manure as a source of ARGs in a survey of 34 garden products, 3 recently landscaped soils, and 5 native soils. DNA was extracted from these soils and quantified for 5 ARGs, intI1, and 16S rRNA. This study found that both absolute and relative gene abundances in garden products ranged from approximately two to greater than four orders of magnitude higher than those observed in native soils. Garden products with Organic Materials Review Institute (OMRI) certification did not have significantly different ARG abundances. Results here indicate that garden products are important sources of ARGs to gardens, lawns, and parks. Graphical abstract

Background The environmental impact of meat consumption requires immediate action. Cultured meat—which is emerging through technologies to grow meat ex vivo—has exciting potential to offset the burden of livestock agriculture by providing an alternative method to sustainably produce meat without requiring individuals to become vegetarian. However, consumer uptake of cultured meat may be challenged by negative public perceptions. Scope and approach In this Review, we assert that the academic sector can play a vital role by understanding and communicating the science of cultured meat to the public. Here, we discuss how crosstalk between the science and technology of cultured meat and the behavioral sciences will be critical to overcome challenges in public perceptions, and ultimately to realize the environmental benefits of cultured meat. We identify research and outreach priorities for the academic sector as well as potential policy actions to achieve the maximum benefits of cultured meat for planetary health.

Most climate change mitigation policies, including those of higher education institutions, do not include food system greenhouse gas emissions (GHGE). Yet the food system contributes ∼30% of anthro...

Green stormwater infrastructure systems, such as biofilters, provide many water quality and other environmental benefits, but their ability to remove human pathogens and antibiotic resistance genes (ARGs) from stormwater runoff is not well documented. In this study, a field scale biofilter in Southern California (USA) was simultaneously evaluated for the breakthrough of a conservative tracer (bromide), conventional fecal indicators, bacterial and viral human-associated fecal source markers (HF183, crAssphage, and PMMoV), ARGs, and bacterial and viral pathogens. When challenged with a 50:50 mixture of untreated sewage and stormwater (to mimic highly contaminated storm flow) the biofilter significantly removed (p0.05) 14 of 17 microbial markers and ARGsin descending order of concentration reduction: ermB (2.5 log(base 10) reduction)Salmonella (2.3)adenovirus (1.9)coliphage (1.5)crAssphage (1.2)E. coli (1.0) ∼ 16S rRNA genes (1.0) ∼ fecal coliform (1.0) ∼ intl1 (1.0)Enterococcus (0.9) ∼ MRSA (0.9) ∼ sul1 (0.9)PMMoV (0.7)Entero1A (0.5). No significant removal was observed for GenBac3, Campylobacter, and HF183. From the bromide data, we infer that 0.5 log-units of attenuation can be attributed to the dilution of incoming stormwater with water stored in the biofilter; removal above this threshold is presumably associated with non-conservative processes, such as physicochemical filtration, die-off, and predation. Our study documents high variability (100-fold) in the removal of different microbial contaminants and ARGs by a field-scale stormwater biofilter operated under transient flow and raises further questions about the utility of human-associated fecal source markers as surrogates for pathogen removal.

Nitrogen (N) in urban runoff is often treated with green infrastructure including biofilters. However, N fates across biofilters are insufficiently understood because prior studies emphasize low N loading under laboratory conditions, or use "steady-state" flow regimes over short time scales. Here, we tested field scale biofilter N fates during simulated storms delivering realistic transient flows with high N loading. Biofilter outflow ammonium (NH

A research-based course was developed to investigate the legacy of soil lead (Pb) pollution in Los Angeles, California. During the course, undergraduate and graduate students collected a total of 270 soil samples for analyses of metal (loid) concentrations in different land-use types (residential, park, and school). Residential soils had significantly higher Pb concentrations than other land uses (p 0.01) exceeding the California recommended safety level for soil Pb (80 mg/kg) at the highest frequency (64% of samples), followed by schools (42%) and parks (6.0%). Soil Pb from all 87 census block groups was correlated with battery recycling plant and railroad proximity as geospatial indicators of childhood Pb exposure risk. Meanwhile, census block groups with higher Pb levels were correlated with higher percentages of the following population: those without health insurance, without college degrees, with a lower median household income and income below the poverty line, and ethnic and racial minorities (r = -0.46 to 0.59, p 0.05). Principal component regression models significantly improved soil Pb estimation over correlation analysis by incorporating sociodemographic, economic, and geospatial risk factors for Pb exposure (R

Wildfires increase runoff and sediment yields that impact downstream ecosystems. While the effects of wildfire on stream water quality are well documented, oceanic responses to wildfire remain poorly understood. Therefore, this study investigated oceanic responses to the 2018 Woolsey Fire using satellite remote sensing and in situ data analyses. We examined 2016–2020 turbidity plume (n = 192) and 2008–2020 fecal indicator bacteria (FIB, n = 15,015) measurements at variable proximity to the Woolsey Fire. Shifts in coastal water quality were more pronounced in the “inside” region, which drained the burn area. The inside region experienced 2018–2019 plume surface area monthly means that were 10 and 9 times greater than 2016–2017 and 2017–2018 monthly means, respectively. Further, linear regressions showed that 2018–2019 three-day precipitation totals produced plumes of greater surface area. We also noted statistically significant increases in the inside region in 2018–2019 total coliform and Enterococcus monthly means that were 9 and 53 times greater than 2008–2018 monthly means, respectively. These results indicate that sediment and microbial inputs to coastal ecosystems can increase substantially post-wildfire at levels relevant to public and environmental health, and underscore the benefit of considering remote sensing and in situ measurements for water quality monitoring.

The goal of this study was to evaluate the impact of a two-quarter freshman course series entitled “Food: A Lens for Environment and Sustainability” (Food cluster) on the carbon footprint of food choices by college freshmen attending a large public university in California. Students enrolled in the course completed a baseline questionnaire about their diets in early fall quarter and then again at follow-up, about 6 months later at the end of the winter quarter. The control group consisted of freshmen enrolled in a different course series entitled “Evolution of the Cosmos and Life” (Cosmos cluster). The instruction in the Food cluster included lecture material on general environmental science and life cycle analyses of food, an analysis of a reading comparing the environmental footprint of various types of meats, and classroom exercises to calculate the environmental footprint of typical foods. The Cosmos cluster instruction included climate change, but no information about food. While the two groups were statistically indistinguishable at baseline, throughout the period of the study, Food cluster students decreased (a) their overall dietary carbon footprint for a 2000-kcal normalized diet by 7% (p = 0.062), (b) the beef component of their dietary carbon footprint by 19% (p = 0.024), and (c) their reported ruminant consumption by 28% (p

In urban areas, untreated stormwater runoff can pollute downstream surface waters. To intercept and treat runoff, low-impact or "green infrastructure" approaches such as using biofilters are adopted. Yet, actual biofilter pollutant removal is poorly understood; removal is often studied in laboratory columns, with variable removal of viable and culturable microbial cell numbers including pathogens. Here, to assess bacterial pollutant removal in full-scale planted biofilters, stormwater was applied, unspiked or spiked with untreated sewage, in simulated storm events under transient flow conditions, during which biofilter influents versus effluents were compared. Based on microbial biomass, sequences of bacterial community genes encoding 16S rRNA, and gene copies of the human fecal marker HF183 and of the Enterococcus spp. marker Entero1A, removal of bacterial pollutants in biofilters was limited. Dominant bacterial taxa were similar for influent versus effluent aqueous samples within each inflow treatment of either spiked or unspiked stormwater. Bacterial pollutants in soil were gradually washed out, albeit incompletely, during simulated storm flushing events. In post-storm biofilter soil cores, retained influent bacteria were concentrated in the top layers (0-10 cm), indicating that the removal of bacterial pollutants was spatially limited to surface soils. To the extent that plant-associated processes are responsible for this spatial pattern, treatment performance might be enhanced by biofilter designs that maximize influent contact with the rhizosphere.

The synergetic effects of metal(loid)s and soil characteristics on bacterial antibiotic resistance genes (ARGs) in green stormwater infrastructure (GSI) has been relatively understudied. Surface soil samples from six GSIs in Southern California over three time periods were assessed for selected ARGs, class 1 integron-integrase genes (intI1), 16S rRNA genes, and bioavailable and total concentrations of nine metal(loid)s, to investigate the relationships among ARGs, soil characteristics, and co-occurring metal(loid)s. Significant correlations existed among relative gene abundances (sul1, sul2, tetW, and intI1), total metal(loid)s (arsenic, copper, lead, vanadium, and zinc), and bioavailable metal(loid) (arsenic) (r = 0.29-0.61, padj

In this paper, we explore the use of unsteady transit time distribution (TTD) theory to model pollutant removal in biofilters, a popular form of nature-based or “green” stormwater infrastructure (G...

Many important diseases are showing resistance to commonly used antibiotics, and the resistance is potentially caused by widespread use of antibiotics for maintaining human health and improving food production. Antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB) are associated with this increase, and their fate in water resource recovery facilities is an important, emerging area of research. This literature review summarizes current findings of worldwide research on the fate of ARB and ARGs in various types of treatment plants. Twenty-five published studies were reviewed which contained 215 observations in activated sludge, membrane bioreactors, anaerobic digestion, constructed wetlands, coagulation-filtration, and three types of disinfection. We found 70% decreased observations, 18% increased observations, and 12% unchanged observations of all observations in all treatment processes. Resistance genes to tetracycline were most often observed, but more studies are needed in other antibiotic resistance genes. The causes for increased abundance of ARGs and ARB are not well understood, and further studies are warranted. PRACTITIONER POINTS: Antibiotic resistance is increasing with concern that treatment plants may acclimate bacteria to antibiotics. A literature survey found 215 resistance observations with 70% decreased, 18% increased, 12% unchanged after treatment. The type of treatment process is important with activated sludge showing the greatest reductions.

Los Angeles has a long history of lead (Pb) contamination due to automobile emissions, industrial processes, and Pb-containing paint. Although the amount of Pb coming from these sources has been reduced or eliminated, exposure to Pb-contaminated soil is still a concern. Contaminated soil in urban parks may constitute an important exposure route, since children are particularly vulnerable to the toxic effects of Pb. While the current EPA clean up level is 400 parts per million (ppm) in recreational and residential areas, the Office of Environmental Health Hazard Assessment (OEHHA) of California revised the soil-screening level to 80 ppm, based on a 1 μg/dL increase of blood level that children experience. In this work, top soil samples in triplicate were taken from each of 100 urban parks in Los Angeles and analyzed to determine Pb concentrations and soil properties. Results show that the average Pb concentration in park soil was 65.5 ppm (range: 0.969–363 ppm), with 35 parks exceeding the California guideline of 80 ppm based on the average Pb concentration measured at each park. Pb concentrations in 42 parks exceeded the background value of 19.7 ppm (by a factor of 3–17). However, variation in measured levels of Pb within most parks was high (>10% RSD in 89 parks). Parks containing elevated Pb concentrations in soil were distributed across many areas of Los Angeles, including central Los Angeles, Beverly Hills, Inglewood, and Central Alameda. Children might potentially suffer from an estimated 1–4 μg/dL increase of blood Pb level according to LeadSpread model. Pb concentrations did not significantly correlate with most soil properties, except for silt (ρ = 0.226, p = 0.012). Additionally, soil from sandy loam contained significantly higher Pb concentrations as compared to soil from loamy sand (p = 0.008). Pb concentrations were significantly correlated with park age (ρ = −0.319, p = 0.033) and were generally lower in areas located away from major roads. Monitoring of parks with high levels of Pb as well as investigation of unexamined regions in Los Angeles are needed.

As both the need for reuse of reclaimed wastewater and the burden placed on existing wastewater treatment plants increase, so does the need for methods that can reliably, rapidly and economically identify human-associated contamination. A survey of surface water quality was conducted in Baja California, Mexico where inadequate infrastructure or its inefficient operation leads to poor water quality. The HF183 and Bacteroides thetaiotaomicron (B. theta) human-associated gene markers were detected in 84% and 82% of samples collected during dry weather, illustrating evidence of widespread human fecal contamination. In addition, an inversely-coupled (Inv-IMS/ATP) viability-based assay for detection of B. theta was developed and applied for rapid detection and screening of human-associated fecal contamination. The Inv-IMS/ATP assay was able to effectively differentiate between surface waters impacted with human fecal contamination, and B. theta levels measured by Inv-IMS/ATP were highly correlated with HF183 and B. theta human marker measurements (r = 0.76; r = 0.82) in complex surface water samples. In areas with widespread human fecal contamination and limited access to more expensive methods, a multi-pronged approach utilizing a combination of methods including the Inv-IMS/ATP assay for rapid evaluation and screening of surface water quality alongside human-associated genetic markers may improve risk assessment and surveillance capabilities.

We have reported that motivation for sucrose is increased in rats fed a moderate (31%) mixed-fat diet for 4–6 wk. In this study, rats were fed diets containing 32% stearic (STEAR) or palmitic (PALM) acid, and behavior, metabolic profile, and cell signals were compared with those of rats fed a matched low-fat diet (LF; 11% fat) diet. Rats fed STEAR or PALM increased sucrose motivation relative to LF rats (one-way ANOVA for lever presses; P = 0.03). Diet did not change fasting glucose, insulin, total cholesterol, triglycerides, intravenous glucose tolerance test glucose profile, percent body fat, or total kilocalories, although kilocalories as fat were increased (ANOVA, P < 0.05). Cell signals were assessed in rats ranked from high to low sucrose motivation. Diet did not alter Thr and Ser phosphorylation of Akt in the medial hypothalamus (HYP) and striatum (STR). However, Ser phosphorylation of GSK3Β was decreased in HYP and STR from both high- and low-performer tertiles of STEAR and PALM rats (ANOVA within each brain region, P < 0.05). Two histone 3 (H3) modifications were also assessed. Although there was no effect of diet on the transcription-repressive H3 modification, H3K27me3, the transcription-permissive H3 modification, H3K4me3, was significantly decreased in the HYP of high performers fed PALM or STEAR (ANOVA, P = 0.013). There was no effect of diet on H3K4me3 levels in HYP of low performers, or in STR. Our findings suggest signal-specific and brain region-specific effects of PALM or STEAR diets and may link downstream signaling effects of GSK3Β activity and H3 modifications with enhanced motivational behavior.

In this study, the aging of culturable FIB and DNA representing genetic markers for Enterococcus spp. (ENT1A), general Bacteroides (GB3), and human-associated Bacteroides (HF183) in freshwater sediments was evaluated. Freshwater sediment was collected from four different sites within the upper and lower reach of the Topanga Creek Watershed and two additional comparator sites within the Santa Monica Bay, for a total of six sites. Untreated (ambient) and oven-dried (reduced microbiota) sediment was inoculated with 5% sewage and artificial freshwater. Microcosms were held for a 21-day period and sampled on day 0, 1, 3, 5, 7, 12, and 21. There were substantial differences in decay among the sediments tested, and decay rates were related to sediment characteristics. In the ambient sediments, smaller particle size and higher levels of organic matter and nutrients (nitrogen and phosphorus) were associated with increased persistence of the GB3 marker and culturable Escherichia coli (cEC) and enterococci (cENT). The HF183 marker exhibited decay rates of −0.50 to −0.96 day −1 , which was 2–5 times faster in certain ambient sediments than decay of culturable FIB and the ENT1A and GB3 markers. The ENT1A and GB3 markers decayed at rates of between −0.07 and −0.28 and −0.10 to −0.44 day −1 , and cEC and cENT decayed at rates of between −0.22 and −0.81 and −0.03 and −0.40 day −1 , respectively. In the oven-dried sediments, increased persistence of all indicators and potential for limited growth of culturable FIB and the GB3 and ENT1A markers was observed. A simplified two-box model using the HF183 marker and cENT decay rates generated from the microcosm experiments was applied to two reaches within the Topanga Canyon watershed in order to provide context for the variability in decay rates observed. The model predicted lower ambient concentrations of enterococci in sediment in the upper (90 MPN g −1 ) versus lower Topanga watershed (530 MPN g −1 ) and low ambient levels of the HF183 marker (below the LLOQ) in sediments in both lower and upper watersheds. It is important to consider the variability in the persistence of genetic markers and FIB when evaluating indicators of fecal contamination in sediments, even within one watershed.

Groundwater contamination by arsenic (As) is a serious public health concern in many different areas worldwide, particularly in the Bengal region. Mobilization and fate of As in natural waters is controlled by a variety of factors including the presence of natural organic matter (NOM). This study experimentally determined conditional distribution coefficients (with KD defined as the ratio between As bound to NOM and truly dissolved As) and apparent stability constants between AsIII oxyanions and NOM from cow dung, chicken dung, and Bangladeshi aquaculture pond sediment prior to and after one year of operation. As-sorption experiments with cow dung as the source of NOM resulted in the highest range for log KD, from 4.7 to 6.3. Pond sediment from Bangladesh after a year of operation for fish production showed greater affinity for binding As oxyanions than fresh sediment prior to fish production. PHREEQCI modeling using constants derived from the experiments along with water chemistry parameters typical for the site supports the dominance of AsIII oxyanion-NOM complexation in this system. Models employing constants from previous studies using purified NOM considerably underestimate observed complexation by environmental NOM; thus, applying site-specific constants to geochemical models will better predict As speciation for the field site.

This study investigated causes of persistent fecal indicator bacteria (FIB) in beach sand under the pier in Santa Monica, CA. FIB levels were up to 1,000 times higher in sand underneath the pier than that collected from adjacent to the pier, with the highest concentrations under the pier in spring and fall. Escherichia coli (EC) and enterococci (ENT) under the pier were significantly positively correlated with moisture (ρ = 0.61, p < 0.001, n = 59; ρ = 0.43, p < 0.001, n = 59, respectively), and ENT levels measured by qPCR (qENT) were much higher than those measured by membrane filtration (cENT). Microcosm experiments tested the ability of EC, qENT, cENT, and general Bacteroidales (GenBac) to persist under in-situ moisture conditions (10% and 0.1%). Decay rates of qENT, cENT, and GenBac were not significantly different from zero at either moisture level, while decay rates for EC were relatively rapid during the microcosm at 10% moisture (k = 0.7 days(−1)). Gull/pelican marker was detected at eight of 12 sites and no human-associated markers (TaqHF183 and HumM2) were detected at any site during a one-day site survey. Results from this study indicate that the high levels of FIB observed likely stem from environmental sources combined with high persistence of FIB under the pier.

Background: Dietary patterns affect both human health and environmental sustainability. Prior research found a ten-unit course on food systems and environmental sustainability shifted dietary intake and reduced dietary carbon footprint among college students. This research evaluated the impact of a similar, more scalable one-unit Foodprint seminar taught at multiple universities. Methods: We used a quasi-experimental pre-post nonequivalent comparison group design (n = 176). As part of the Menus of Change University Research Collaborative, research was conducted at three university campuses in California over four academic terms. All campuses used the same curriculum, which incorporates academic readings, group discussions, and skills-based exercises to evaluate the environmental footprint of different foods. The comparison group comprised students taking unrelated one-unit courses at the same universities. A questionnaire was administered at the beginning and end of each term. Results: Students who took the Foodprint seminar significantly improved their reported vegetable intake by 4.7 weekly servings relative to the comparison group. They also reported significantly decreasing intake of ruminant meat and sugar-sweetened beverages. As a result of dietary shifts, Foodprint seminar students were estimated to have significantly decreased their dietary carbon footprint by 14%. Conclusions: A scalable, one-unit Foodprint seminar may simultaneously promote environmental sustainability and human health.

Background. Many children in low- and middle-income countries face enhanced risks of exposure to contaminants via the environment, parental occupation, and other routes. While mercury (Hg) is a global pollutant whose transport properties allow it to have an impact even in pristine areas, the presence of significant Hg sources in the developing world can cause localized effects that are more severe than those observed in other areas. Objectives. This paper provides a narrative review of sources of Hg exposure to people in the developing world with a particular focus on children, and presents an overview of key aspects to this important issue. Methods. We searched Web of Knowledge and Google Scholar using keywords including combinations of “mercury” and one or more of the following: “children,” “exposure,” “breast milk,” “artisanal mining,” “prenatal,” “religion,” “medicine,” “dental amalgam,” “chlor-alkali,” “VCM,” “vaccine,” “e-waste,” “industry,” “beauty,” “cosmetics,” “strategies,” “child labor,” “costs,” and “developing countries” to find peer-reviewed articles pertaining to Hg exposure in the developing world. Results. Sources of Hg exposure include mining, consumption, industrial operations, religious practices, traditional medicines, beauty products, vaccines, dental amalgams, and waste scavenging and recycling. Conclusion. Children in the developing world are often subject to higher levels of Hg exposure than those living in developed countries due to the higher prevalence of Hg-intensive industrial processes and consumer products, lack of environmental regulation, and limits in mobility and food choices, among other factors. This issue can be addressed through additional research to fill in data gaps on exposure sources, establish sound and enforceable policies, and increase education and participation in affected communities. Challenges to addressing this problem include limited resources for needed equipment, training, and manpower to implement solutions. Competing Interests. The authors declare no competing financial interests.

Elevated levels of fecal indicator bacteria (FIB) have been observed at Topanga Beach, CA, USA. To identify the FIB sources, a microbial source tracking study using a dog-, a gull- and two human-associated molecular markers was conducted at 10 sites over 21 months. Historical data suggest that episodic discharge from the lagoon at the mouth of Topanga Creek is the main source of bacteria to the beach. A decline in creek FIB/markers downstream from upper watershed development and a sharp increase in FIB/markers at the lagoon sites suggest sources are local to the lagoon. At the lagoon and beach, human markers are detected sporadically, dog marker peaks in abundance mid-winter, and gull marker is chronically elevated. Varied seasonal patterns of FIB and source markers were identified showing the importance of applying a suite of markers over long-term spatial and temporal sampling to identify a complex combination of sources of contamination.

Widespread prevalence of multidrug and pandrug-resistant bacteria has prompted substantial concern over the global dissemination of antibiotic resistance genes (ARGs). Environmental compartments can behave as genetic reservoirs and hotspots, wherein resistance genes can accumulate and be laterally transferred to clinically relevant pathogens. In this work, we explore the ARG copy quantities in three environmental media distributed across four cities in California and demonstrate that there exist city-to-city disparities in soil and drinking water ARGs. Statistically significant differences in ARGs were identified in soil, where differences in blaSHV gene copies were the most striking; the highest copy numbers were observed in Bakersfield (6.0 × 10–2 copies/16S-rRNA gene copies and 2.6 × 106 copies/g of soil), followed by San Diego (1.8 × 10–3 copies/16S-rRNA gene copies and 3.0 × 104 copies/g of soil), Fresno (1.8 × 10–5 copies/16S-rRNA gene copies and 8.5 × 102 copies/g of soil), and Los Angeles (5.8 × 10–6 copies/16S-rRNA gene copies and 5.6 × 102 copies/g of soil). In addition, ARG copy numbers in the air, water, and soil of each city are contextualized in relation to globally reported quantities and illustrate that individual genes are not necessarily predictors for the environmental resistome as a whole.

This study investigated causes of persistent fecal indicator bacteria (FIB) in beach sand under the pier in Santa Monica, CA. FIB levels were up to 1000 times higher in sand underneath the pier than that collected from adjacent to the pier, with the highest concentrations under the pier in spring and fall. Escherichia coli (EC) and enterococci (ENT) under the pier were significantly positively correlated with moisture (ρ = 0.61, p

The performance and specificity of the covalently linked immunomagnetic separation-ATP (Cov-IMS/ATP) method for the detection and enumeration of enterococci was evaluated in recreational waters. Cov-IMS/ATP performance was compared with standard methods: defined substrate technology (Enterolert; IDEXX Laboratories), membrane filtration (EPA Method 1600), and an Enterococcus -specific quantitative PCR (qPCR) assay (EPA Method A). We extend previous studies by (i) analyzing the stability of the relationship between the Cov-IMS/ATP method and culture-based methods at different field sites, (ii) evaluating specificity of the assay for seven ATCC Enterococcus species, (iii) identifying cross-reacting organisms binding the antibody-bead complexes with 16S rRNA gene sequencing and evaluating specificity of the assay to five nonenterococcus species, and (iv) conducting preliminary tests of preabsorption as a means of improving the assay. Cov-IMS/ATP was found to perform consistently and with strong agreement rates (based on exceedance/compliance with regulatory limits) of between 83% and 100% compared to the culture-based Enterolert method at a variety of sites with complex inputs. The Cov-IMS/ATP method is specific to five of seven different Enterococcus spp. tested. However, there is potential for nontarget bacteria to bind the antibody, which may be reduced by purification of the IgG serum with preabsorption at problematic sites. The findings of this study help to validate the Cov-IMS/ATP method, suggesting a predictable relationship between the Cov-IMS/ATP method and traditional culture-based methods, which will allow for more widespread application of this rapid and field-portable method for coastal water quality assessment.

Some molecular methods for tracking fecal pollution in environmental waters have both PCR and quantitative PCR (qPCR) assays available for use. To assist managers in deciding whether to implement newer qPCR techniques in routine monitoring programs, we compared detection limits (LODs) and costs of PCR and qPCR assays with identical targets that are relevant to beach water quality assessment. For human-associated assays targeting Bacteroidales HF183 genetic marker, qPCR LODs were 70 times lower and there was no effect of target matrix (artificial freshwater, environmental creek water, and environmental marine water) on PCR or qPCR LODs. The PCR startup and annual costs were the lowest, while the per reaction cost was 62% lower than the Taqman based qPCR and 180% higher than the SYBR based qPCR. For gull-associated assays, there was no significant difference between PCR and qPCR LODs, target matrix did not effect PCR or qPCR LODs, and PCR startup, annual, and per reaction costs were lower. Upgrading to qPCR involves greater startup and annual costs, but this increase may be justified in the case of the human-associated assays with lower detection limits and reduced cost per sample.

Evidence from experimental models has suggested that acute activation of brain stress and anxiety pathways impacts subsequent behaviors that are mediated or modulated by limbic circuitry. There have been limited investigations of prior or chronic activation of these pathways on subsequent limbic-mediated behaviors. In this study, we tested whether recurrent administration of the anxiogenic compound yohimbine (YOH) could have post-injection effects on brain activation, stress hormones, and performance in sucrose self-administration and startle response paradigms. Rats received six injections across two weeks of either 2mg/kg YOH or saline. Behavioral evaluation confirmed the continued efficacy of the YOH regimen, and increased adrenal corticosterone (CORT) was observed. Several days following YOH or SAL administration, cFos, CORT and adrenocorticotropin hormone (ACTH), and behavioral performance were measured. cFos was elevated post-YOH in the hippocampus; ventral tegmental area/zona inserta; and central and medial nuclei of the amygdala. This activation is consistent with a sustained effect of YOH to activate fear and anxiety circuitries in the CNS. CORT but not ACTH was elevated in the YOH-rats following startle testing. Self-administration and startle tests suggested an increase of non-specific activity in the post-YOH rats; there was no increase in sucrose self-administration or startle response per se. Our findings suggest that recurrent YOH administration may prove a useful and reliable model for simulating recurrent stress/anxiety, and that enhancements to the paradigm such as higher or more frequent dosing of YOH could yield stronger or more extensive behavioral effects.

The Destruction of the Medieval Chinese Aristocracy, by Nicolas Tackett. Cambridge, Harvard University Asia Center, 2014. Harvard-Yenching Institute Monograph Series 93. xv, 281 pp. $49.95 US (cloth). The book under review is a substantive contribution to social history, historiography, human geography, and material culture in Tang China (618-906). It is an admirable application of gis (China Historical System) and social network analysis to sinology. The research undertaken by Tackett is remarkable, with the creation of a huge database derived from several thousands of excavated epitaphs recording the lives of men and women from the seventh to the tenth centuries. He used the gis to generate comparative charts plotting the transformation and migratory pathways of descendants of the medieval aristocracy that traced its origins to the first century. Checking the epigraphic evidence against digital biographies, anecdotal collections, and dynastic histories, he provides empirical data to confirm the research outcomes of two generations of Chinese, Japanese, and western scholarship on the Chinese medieval aristocracy. Tackett begins with the tomb epitaph of Ms. Lu, who hailed from the prestigious Fanyang (Beijing) clan and married into an eminent clan in Luoyang. Her son passed the highest level of examinations and her son-in-law became chief minister. In 880 when the Huang Chao (d. 884) rebels swept into the capitals of Luoyang and Chang'an, she perished along with four of her five children, who died without heirs. Only one son survived, and a nephew buried her with three epitaphs that form part of Tackett's epigraphic data. The extinction of the clans of her father, husband, and son-in-law mirrored the broader crisis of the medieval aristocracy and its total disappearance from the mass killings of the members. Chapter one presents the medieval aristocracy as a hierarchy of top-ranked, eminent, and famous-surname clans that survived several dynastic changes, on the strength of breeding, education, morality, public service and a strong social network sustained by endogamous marriages. The epitaph shows the individual's life passages as well as clan descent and social networks. The materiality of the epitaph (such as the length of the epitaph, calligraphy, and quality of tombstone) is indicative of clan hierarchy and differentiated wealth among the elites. Charts generated from plotting 6,255 epitaphs show that the top-ranked and eminent great clans moved into Chang'an and Luoyang while less distinguished clans relocated to peripheral regions. The next chapter uses geographic data to show that the capital elites were sharply distinct from the provincial elites. Based in the Chang'an/ Luoyang / surrounding region, the capital elites dominated key central government posts for a number of generations. The provincial elite spread in the provinces and only one or two generations held public office. Downward mobility is observed when certain capital elites transferred to the provinces for term appointments, while upward mobility can be seen where wealthy merchants, clergy, military, and other non-officeholder elite families moved into the capital region. …

A biographer of outstanding women, art and music critic Hayter-Menzies recently published Imperial Masquerade: The Legend of Princess Der Ling (2008) and The Empress and Mrs. Conger (2011) with Hon...

We have previously reported that a moderately high fat diet increases motivation for sucrose in adult rats. In this study, we tested the motivational, neurochemical, and metabolic effects of the high fat diet in male rats transitioning through puberty, during 5-8 weeks of age. We observed that the high fat diet increased motivated responding for sucrose, which was independent of either metabolic changes or changes in catecholamine neurotransmitter metabolites in the nucleus accumbens. However, AGRP mRNA levels in the hypothalamus were significantly elevated. We demonstrated that increased activation of AGRP neurons is associated with motivated behavior, and that exogenous (third cerebroventricular) AGRP administration resulted in significantly increased motivation for sucrose. These observations suggest that increased expression and activity of AGRP in the medial hypothalamus may underlie the increased responding for sucrose caused by the high fat diet intervention. Finally, we compared motivation for sucrose in pubertal vs. adult rats and observed increased motivation for sucrose in the pubertal rats, which is consistent with previous reports that young animals and humans have an increased preference for sweet taste, compared with adults. Together, our studies suggest that background diet plays a strong modulatory role in motivation for sweet taste in adolescent animals.

Current microbial source tracking methods heavily rely on the use of quantitative PCR (qPCR) assays to differentiate human and non-human sources of fecal contamination. However, traditional qPCR measures DNA from viable, viable but not culturable (VBNC), and dead cells, which may confound the use of this technique for detecting recent fecal contamination from waters receiving treated sewage effluent. In this study, fecal indicator bacteria (FIB), six host-associated markers, and two viability-based methods for rapid detection and assessment of fecal contamination were used in a microbial source tracking study to identify sources impairing water quality and sediments within the San Antonio de los Buenos watershed in Tijuana, Mexico. Horse- and gull-associated markers were detected in 4 and 8% of samples tested, respectively. The human- and dog-associated markers were positive in 74 and 63% of watershed samples and 92 and 75% of storm drain samples, respectively. Propidium monoazide (PMA) successfully inhibited amplification of DNA from dead cells in environmental creek waters that receive large volumes of treated wastewater effluent. Accordingly, PMA-qPCR measurements were more comparable to measurements made by culture-based methods (IDEXX). The covalently linked immunomagnetic separation/adenosine triphosphate (Cov-IMS/ATP) method showed a strong linear relationship to culture methods when compared to measurements made by the qPCR Entero1a assay. Both the PMA-qPCR and the Cov-IMS/ATP methods show promise for improved assessment of water quality and recent fecal contamination in sewage impacted waters, including areas receiving discharge from wastewater treatment plants, where measurement by qPCR does not effectively differentiate between DNA from live and dead cells. This study serves as an important positive control for non-point source pollution studies.

Batch and column laboratory experiments were conducted on natural sediment and groundwater samples from a contaminated site in Maine, USA with the aim of lowering the dissolved arsenate [As(V)] concentrations through chemical enhancement of natural attenuation capacity. In batch factorial experiments, two levels of treatment for three parameters (pH, Ca, and Fe) were studied at different levels of phosphate to evaluate their impact on As(V) solubility. Results illustrated that lowering pH, adding Ca, and adding Fe significantly increased the sorption capacity of sediments. Overall, Fe amendment had the highest individual impact on As(V) levels. To provide further evidence for the positive impact of Ca on As(V) adsorption, isotherm experiments were conducted at three different levels of Ca concentrations. A consistent increase in adsorption capacity (26-37%) of sediments was observed with the addition of Ca. The observed favorable effect of Ca on As(V) adsorption is likely caused by an increase in the surface positive charges due to surface accumulation of Ca2+ ions. Column experiments were conducted by flowing contaminated groundwater with elevated pH, As(V), and phosphate through both uncontaminated and contaminated sediments. Potential in-situ remediation scenarios were simulated by adding a chemical amendment feed to the columns injecting Fe(II) or Ca as well as simultaneous pH adjustment. Results showed a temporary and limited decrease in As(V) concentrations under the Ca treatment (39-41%) and higher levels of attenuation in Fe(II) treated columns (50-91%) but only after a certain number of pore volumes (18-20). This study illustrates the importance of considering geochemical parameters including pH, redox potential, presence of competing ions, and sediment chemical and physical characteristics when considering enhancing the natural attenuation capacity of sediments to mitigate As contamination in natural systems.