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Soil organic carbon (SOC) is a soil health indicator and understanding dynamics changing SOC stocks will help achieving net zero goals. Here we present four datasets featuring 11,750 data points covering co-located aboveground and below-ground metrics for exploring ecosystem SOC dynamics. Five sites across England with an established land use contrast, grassland and woodland next to each other, were rigorously sampled for aboveground (n = 109), surface (n = 33 soil water release curves), topsoil, and subsoil metrics. Commonly measured soil metrics were analysed in five soil increments for 0-1 metre (n = 4550). Less commonly measured soil metrics which were assumed to change across the soil profile were measured on a subset of samples only (n = 3762). Additionally, we developed a simple method for soil organic matter fractionation using density fractionation which is part of the less common metrics. Finally, soil metrics which may impact SOC dynamics, but with less confidence as to their importance across the soil profile were only measured on topsoil (~5-15 cm = mineral soil) and subsoil (below 50 cm) samples (n = 2567).
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Carbono , Pradaria , Solo , Solo/química , Carbono/análise , Inglaterra , Florestas , EcossistemaRESUMO
The transfer of dissolved organic carbon (DOC) from land to watercourses plays a major role in the carbon cycle, and in the transport and fate of associated organic and inorganic contaminants. We investigated, at global scale, how the concentrations and properties of riverine DOC depend upon combinations of terrestrial source solutions. For topsoil, subsoil, groundwater and river solutions in different Köppen-Geiger climatic zones, we compiled published and new values of DOC concentration ([DOC]), radiocarbon signature (DO14C), and specific UV absorbance (SUVA). The average value of each DOC variable decreased significantly in magnitude from topsoil to subsoil to groundwater, permitting the terrestrial sources to be distinguished. We used the terrestrial data to simulate the riverine distributions of each variable, and also relationships between pairs of variables. To achieve good matches between observed and simulated data, it was necessary to optimise the distributions of water fractions contributed by each of the three terrestrial sources, and also to reduce the mean input terrestrial [DOC] values, to about 60% of the measured ones. One possible explanation for the required lowering of the modelled terrestrial [DOC] values might be unrepresentative sampling of terrestrial DOC, including dilution effects; another is the loss of DOC during riverine transport. High variations in simulated riverine DOC variables, which match observed data, are due predominantly to variations in source solution values, with a lesser contribution from the different combinations of source waters. On average, most DOC in rivers draining catchments with forest and/or grass-shrub land cover comes in similar amounts from topsoil and subsoil, with about 10% from groundwater. In rivers draining croplands, subsoil and groundwater solutions are the likely dominant DOC sources, while in wetland rivers most DOC is from topsoil.
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Matéria Orgânica Dissolvida , Monitoramento Ambiental , Carbono/análise , Ciclo do Carbono , RiosRESUMO
The carbon cycle is a key regulator of Earth's climate. On geological time-scales, our understanding of particulate organic matter (POM), an important upper ocean carbon pool that fuels ecosystems and an integrated part of the carbon cycle, is limited. Here we investigate the relationship of planktonic foraminifera-bound organic carbon isotopes (δ13Corg-pforam) with δ13Corg of POM (δ13Corg-POM). We compare δ13Corg-pforam of several planktonic foraminifera species from plankton nets and recent sediment cores with δ13Corg-POM on a N-S Atlantic Ocean transect. Our results indicate that δ13Corg-pforam of planktonic foraminifera are remarkably similar to δ13Corg-POM. Application of our method on a glacial sample furthermore provided a δ13Corg-pforam value similar to glacial δ13Corg-POM predictions. We thus show that δ13Corg-pforam is a promising proxy to reconstruct environmental conditions in the upper ocean, providing a route to isolate past variations in δ13Corg-POM and better understanding of the evolution of the carbon cycle over geological time-scales.
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Foraminíferos , Oceano Atlântico , Carbono/análise , Ciclo do Carbono , Isótopos de Carbono/análise , Ecossistema , Material Particulado , PlânctonRESUMO
INTRODUCTION: Post-traumatic stress disorder (PTSD) and chronic pain are frequently co-morbid conditions in the U.S. veteran population. Although several theories about the cause of increased pain prevalence in individuals with PTSD have been presented, no synthesis of primary data informing the impact of co-morbid PTSD and pain has been completed. The purpose of this study was to systematically review the literature and quantify disability, function, and pain-related beliefs and outcomes in veterans with PTSD compared to veterans without PTSD. MATERIALS AND METHODS: A systematic search of three electronic databases was conducted. Inclusion criteria required pain-related comparison of veterans with PTSD to those without PTSD. Primary outcome measures and standardized mean differences (SMDs) were assessed for pain, function, disability, pain beliefs, and healthcare utilization using a random effects model. RESULTS: 20 original research studies met inclusion criteria and were assessed for quality and outcomes of interest. The majority of studies were cross-sectional. Veterans with PTSD and pain demonstrated higher pain (SMD = 0.58, 95% CI 0.28-0.89), disability (SMD = 0.52, 95%CI 0.33-0.71), depression (SMD = 1.40, 95%CI 1.2-1.6), catastrophizing beliefs (SMD = 0.95, 95% CI 0.69-1.2), sleep disturbance (SMD = 0.80, 95% CI 0.57-1.02), and healthcare utilization; they had lower function (SMD = 0.41, 95% CI 0.25-0.56) and pain self-efficacy (SMD = 0.77, 95% CI 0.55-0.99) compared to veterans without PTSD. CONCLUSION: In veterans with chronic pain, PTSD symptomology has a large effect for many negative health-related outcomes. This review supports the need for clinicians to screen and understand the effects of PTSD symptoms on patients with pain. Clinicians should recognize that veterans with PTSD and pain likely have elevated pain catastrophizing beliefs and decreased self-efficacy that should be targeted for intervention.
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Transtornos de Estresse Pós-Traumáticos , Veteranos , Comorbidade , Estudos Transversais , Humanos , Avaliação de Resultados em Cuidados de Saúde , Dor/epidemiologia , Transtornos de Estresse Pós-Traumáticos/complicações , Transtornos de Estresse Pós-Traumáticos/epidemiologiaRESUMO
3D bioprinting is a rapidly evolving industry that has been utilized for a variety of biomedical applications. It differs from traditional 3D printing in that it utilizes bioinks comprised of cells and other biomaterials to allow for the generation of complex functional tissues. Bioprinting involves computational modeling, bioink preparation, bioink deposition, and subsequent maturation of printed products; it is an intricate process where bioink composition, bioprinting approach, and bioprinter type must be considered during construct development. This technology has already found success in human studies, where a variety of functional tissues have been generated for both in vitro and in vivo applications. Although the main driving force behind innovation in 3D bioprinting has been utility in human medicine, recent efforts investigating its veterinary application have begun to emerge. To date, 3D bioprinting has been utilized to create bone, cardiovascular, cartilage, corneal and neural constructs in animal species. Furthermore, the use of animal-derived cells and various animal models in human research have provided additional information regarding its capacity for veterinary translation. While these studies have produced some promising results, technological limitations as well as ethical and regulatory challenges have impeded clinical acceptance. This article reviews the current understanding of 3D bioprinting technology and its recent advancements with a focus on recent successes and future translation in veterinary medicine.
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Vitamin C is an essential nutrient with important antioxidant properties. Higher vitamin C intake appears to be associated with positive effects on cardiovascular risk factors in cohort studies, whereas large randomized controlled clinical trials did not confirm the benefits of supplemental vitamin C on cardiovascular disease (CVD) outcomes. In this overview of systematic reviews and meta-analyses, an "umbrella review," we investigated the effects of vitamin C supplementation on biomarkers of cardiovascular risk, that is, arterial stiffness, blood pressure, endothelial function, glycemic control, and lipid profile. In addition, we assessed the strength of the evidence and the methodological qualities of available studies. Two independent investigators searched 4 databases (Medline, Embase, Scopus, and The Cochrane Library databases) from inception until February 2018. After full text examination, 10 systematic reviews and meta-analyses were included in the umbrella review which included 6409 participants. Three systematic reviews investigated the effects of vitamin C on endothelial function with contrasting results (2 reviews reported a significant effect, and all 3 showed a high heterogeneity [I2>â¯50%]); 1 systematic review reported significant improvement for each of the following risk factors: blood pressure, and blood concentrations of glucose, low-density lipoprotein cholesterol, and triglycerides. There were no overall effects of vitamin C on arterial stiffness and blood concentration of insulin, total cholesterol, and high-density lipoprotein cholesterol, but subgroup analyses revealed some evidence for significant improvements in subpopulations with higher body mass index, higher plasma concentrations of glucose or cholesterol, and low plasma concentration of vitamin C. Results from this umbrella review emphasize the weakness of the current evidence base about effects of vitamin C supplementation on markers of CVD risk. There is limited evidence that some population subgroups (older people, the obese, those with lower vitamin C status at baseline, and those at higher CVD risk) may be more responsive to vitamin C supplementation and offer opportunities for tailored nutritional interventions to improve cardiometabolic health. Future studies should implement a selective recruitment strategy that is informed by evidence-based literature synthesis.
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Antioxidantes/uso terapêutico , Ácido Ascórbico/uso terapêutico , Doenças Cardiovasculares/prevenção & controle , Suplementos Nutricionais , Vitaminas/uso terapêutico , Antioxidantes/farmacologia , Ácido Ascórbico/sangue , Ácido Ascórbico/farmacologia , Biomarcadores/sangue , Pressão Sanguínea , Índice de Massa Corporal , Doenças Cardiovasculares/etiologia , Humanos , Lipídeos/sangue , Metanálise como Assunto , Revisões Sistemáticas como Assunto , Rigidez Vascular/efeitos dos fármacos , Vitaminas/sangue , Vitaminas/farmacologiaRESUMO
The intent of this study was to assess passerine eastern equine encephalitis virus (EEEv) seroprevalence during the breeding season in southern Maine by testing songbird species identified in the literature as amplifying hosts of this virus. In 2013 and 2014, we collected serum samples from songbirds at a mainland site and an offshore island migratory stopover site, and screened samples for EEEv antibodies using plaque reduction neutralization tests. We compared seasonal changes in EEEv antibody seroprevalence in young (hatched in year of capture) and adult birds at the mainland site, and also compared early season seroprevalence in mainland versus offshore adult birds. EEEv seroprevalence did not differ significantly between years at either site. During the early season (May), EEEv antibody seroprevalence was substantially lower (9.6%) in the island migrant adults than in mainland adults (42.9%), 2013-2014. On the mainland, EEEv antibody seroprevalence in young birds increased from 12.9% in midseason (June-August) to 45.6% in late season (September/October), 2013-2014. Seroprevalence in adult birds did not differ between seasons (48.8% vs. 53.3%). EEEv activity in Maine has increased in the past decade as measured by increased virus detection in mosquitoes and veterinary cases. High EEEv seroprevalence in young birds-as compared to that of young birds in other studies-corresponded with two consecutive active EEEv years in Maine. We suggest that young, locally hatched songbirds be sampled as a part of long-term EEEv surveillance, and provide a list of suggested species to sample, including EEEv "superspreaders."
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Anticorpos Antivirais/sangue , Vírus da Encefalite Equina do Leste/imunologia , Estações do Ano , Aves Canoras/sangue , Envelhecimento , Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/veterinária , Infecções por Alphavirus/virologia , Animais , Doenças das Aves/sangue , Doenças das Aves/epidemiologia , Doenças das Aves/virologia , Feminino , Maine/epidemiologia , Masculino , Estudos SoroepidemiológicosRESUMO
OBJECTIVE: To evaluate the performance of a rapid HIV antibody test used with whole blood and oral fluid in settings where the test is likely to be used. DESIGN: In four separate studies, we compared the accuracy of the rapid test performed on whole blood and oral fluid specimens with the results of conventional HIV tests. METHODS: Oral fluid and whole blood from persons of unknown HIV status recruited from clinics, labor and delivery units, and outreach venues were tested with the OraQuick Advance rapid HIV-1/2 antibody test. Sensitivity and specificity were compared with results of the enzyme immunoassay (EIA) and Western blot algorithm used by the study sites. RESULTS: OraQuick sensitivity was 99.7% with whole blood and 99.1% with oral fluid from 327 persons who were HIV antibody positive by the conventional algorithm. OraQuick specificity was 99.9% with whole blood and 99.6% with oral fluid from 12 010 HIV-negative persons; EIA specificity was 99.7%. A cluster of 16 false-positive oral fluid tests occurred in one study, in which specificity was lower (99.0%) than in the other three studies (99.6-99.8%). CONCLUSIONS: In diverse settings in four studies, the OraQuick test showed high sensitivity and specificity for HIV antibody in whole blood and oral fluid specimens. Slightly more false-positive and false-negative results occurred with oral fluid than with whole blood, but performance with both specimen types was similar to, or better than, that of conventional EIAs.
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Sorodiagnóstico da AIDS/métodos , Infecções por HIV/diagnóstico , Saliva/virologia , Western Blotting/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Anticorpos Anti-HIV/análise , Infecções por HIV/imunologia , HIV-1/imunologia , HIV-2/imunologia , Humanos , Valor Preditivo dos Testes , Gravidez , Kit de Reagentes para Diagnóstico , Saliva/imunologia , Sensibilidade e EspecificidadeRESUMO
In this paper we report new data on peat carbon (C), nitrogen (N) and phosphorus (P) concentrations and accumulation rates for 15 sites in the UK. Concentrations of C, N and P measured in peat from five ombrotrophic blanket mires, spanning 4000-10,000years to present were combined with existing nutrient data from ten Scottish ombrotrophic peat bogs to provide the first UK perspective on millennial scale macronutrient concentrations in ombrotrophic peats. Long-term average C, N and P concentrations (0-1.25m) for the UK are 54.8, 1.56 and 0.039wt%, of similar magnitude to the few published comparable sites worldwide. The uppermost peat (0-0.2m) is enriched in P and N (51.0, 1.86, and 0.070wt%) relative to the deeper peat (0.5-1.25m, 56.3, 1.39, and 0.027wt%). Long-term average (whole core) accumulation rates of C, N and P are 25.3±2.2gCm-2year-1 (mean±SE), 0.70±0.09gNm-2year-1 and 0.018±0.004gPm-2year-1, again similar to values reported elsewhere in the world. The two most significant findings are: 1) that a regression model of N concentration on P concentration and mean annual precipitation, based on global meta data for surface peat samples, can explain 54% of variance in N concentration in these UK peat profiles; and 2) budget calculations for the UK peat cores yield an estimate for long-term average N-fixation of 0.8gm-2year-1. Our UK results, and comparison with others sites, corroborate published estimates of N storage in northern boreal peatlands through the Holocene as ranging between 8 and 15Pg N. However, the observed correlation of N% with both mean annual precipitation and P concentration allows a potential bias in global estimates that do not take this into account. The peat sampling data set has been deposited at the NERC Data Centre (Toberman et al., 2016).
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The bill structures of different call types of red crossbills (Loxia curvirostra complex) in western North America usually approximate the predicted optima for foraging on single species of conifers. One clear exception is the call type in the South Hills, Idaho, that is coevolving in an evolutionary arms race with Rocky Mountain lodgepole pine (Pinus contorta ssp. latifolia). Although South Hills crossbills forage only on the cones of these lodgepole pines, their average bill depth is smaller than that predicted to be optimal. Because preliminary data showed that large-billed males were more likely to exhibit symptoms of ectoparasitic mite (Knemidokoptes jamaicensis) infestation, the goal of our study was to further quantify the incidence of mite infestation and determine whether selection by mites may have favored smaller-billed crossbills and thus driven crossbills away from the foraging optimum. We estimated annual survival of both infected and uninfected South Hills crossbills using program MARK, which allows for auxiliary variables such as bill size and sex to be included in survival analyses. Mite infestation depressed crossbill survival and, especially for males, caused directional selection against larger-billed individuals. Such selection may explain why South Hills crossbills have smaller bills than the optimum and why average bill size for males has decreased from 1998 to 2003. This selection may also explain why the degree of sexual size dimorphism has decreased by nearly 50% since 1998.
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Adaptação Biológica , Bico/anatomia & histologia , Ácaros/fisiologia , Passeriformes/anatomia & histologia , Passeriformes/parasitologia , Seleção Genética , Simbiose , Animais , Pesos e Medidas Corporais , Idaho , Masculino , Passeriformes/fisiologia , Pinus/anatomia & histologia , Caracteres Sexuais , Análise de SobrevidaRESUMO
Recent breakthroughs in technology have produced tests for HIV antibody that are highly accurate and easy to use and can give a preliminary result in 20 minutes or less. These rapid HIV tests will be used increasingly in labor and delivery wards, emergency departments, urgent care centers, and the primary care office. They have unique applications for healthcare worker exposures, military operations, public health venues, and developing countries. In this article, Drs Keenan, Keenan, and Branson discuss the advantages and limitations of rapid HIV testing in various settings.
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Infecções por HIV/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , Kit de Reagentes para Diagnóstico , Sorodiagnóstico da AIDS/métodos , Países em Desenvolvimento , Serviço Hospitalar de Emergência , Infecções por HIV/transmissão , Humanos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Medicina Militar , Exposição Ocupacional , Atenção Primária à Saúde , Saúde PúblicaRESUMO
Empirical monitoring studies of catchment-scale Escherichia coli burden to land from agriculture are scarce. This is not surprising given the complexity associated with the temporal and spatial heterogeneity in the excretion of livestock faecal deposits and variability in microbial content of faeces. However, such information is needed to appreciate better how land management and landscape features impact on water quality draining agricultural landscapes. The aim of this study was to develop and test a field-based protocol for determining the burden of E. coli in a small headwater catchment in the UK. Predictions of E. coli burden using an empirical model based on previous best estimates of excretion and shedding rates were also evaluated against observed data. The results indicated that an empirical model utilising key parameters was able to satisfactorily predict E. coli burden on pasture most of the time, with 89% of observed values falling within the minimum and maximum range of predicted values. In particular, the overall temporal pattern of E. coli burden on pasture is captured by the model. The observed and predicted values recorded a disagreement of >1 order of magnitude on only one of the nine sampling dates throughout an annual period. While a first approximation of E. coli burden to land, this field-based protocol represents one of the first comprehensive approaches for providing a real estimate of a dynamic microbial reservoir at the headwater catchment scale and highlights the utility of a simple dynamic empirical model for a more economical prediction of catchment-scale E. coli burden.
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Monitoramento Ambiental/métodos , Escherichia coli/crescimento & desenvolvimento , Microbiologia da Água , Poluição da Água/estatística & dados numéricos , Agricultura , Fezes/microbiologia , Modelos Biológicos , Modelos Teóricos , Qualidade da ÁguaRESUMO
Discharges of coloured effluents into surface waters provide conspicuous evidence of the impact of industry on the environment. The textile industry is an obvious candidate for sources of such discharges. Conventional treatment methods appear to alleviate this situation by removing colour, however the affect on toxicity is less obvious. The objective of this study was to examine the changes in effluent toxicity during the course of two alternative wastewater treatment methods, ozonation and electrochemical oxidation, using a novel toxicity biosensor, GreenScreen EM. The biosensor is capable of measuring both general acute toxicity (cytotoxicity), and more specifically genotoxicity, that is damage to a cell's DNA structure, replication or distribution, caused by substances that may be mutagenic and/or carcinogenic. The biosensor utilises a modified strain of the brewers yeast Saccharomyces cerevisiae, incorporating a gene encoding green fluorescent protein (GFP) linked to the inducible promoter of the DNA damage responsive RAD54 gene. Upon exposure to a genotoxin, the production of GFP is up-regulated in parallel with RAD54, and the resulting cellular fluorescence provides a measure of genotoxicity. Acute toxicity is simultaneously determined by monitoring relative total growth of the cell culture during incubation. The results presented in this paper show that a reduction in colouration does not necessarily correspond to a reduction in effluent toxicity.
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Técnicas Biossensoriais , Mutagênicos/toxicidade , Saccharomyces cerevisiae/efeitos dos fármacos , Eliminação de Resíduos Líquidos/instrumentação , Poluentes Químicos da Água/toxicidade , Cor , Resíduos Industriais , Oxidantes/química , Oxirredução , Ozônio/química , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Purificação da Água/métodosRESUMO
BACKGROUND: In March 2004, the OraQuick rapid HIV antibody test became the first rapid HIV test approved by the US Food and Drug Administration for use on oral fluid specimens. Test results are available in 20 minutes, and the oral fluid test is non-invasive. From August 2004-June 2005, we investigated a sudden increase in false-positive results occurring in a performance study of OraQuick oral-fluid rapid HIV tests in Minnesota. METHODOLOGY/PRINCIPAL FINDINGS: In a field investigation, we reviewed performance study data on oral-fluid and whole-blood OraQuick rapid HIV test device lots and expiration dates and assessed test performance and interpretation with oral-fluid and whole-blood specimens by operators who reported false-positive results. We used multivariate logistic regression to evaluate client demographic and risk characteristics associated with false-positive results. Next, we conducted an incidence study of false-positive OraQuick rapid HIV tests in nine US cities and tested both oral-fluid and finger-stick whole-blood specimens from clients; reactive tests were confirmed with Western blot. Sixteen (4.1%) false-positive oral-fluid results occurred in the performance study from April 15, 2004 through August 31, 2004 with unexpired devices from six test lots among 388 HIV-uninfected clients (specificity, 95.9%; 95% CI: 93.4-97.6). Three test operators who had reported false-positive results performed and interpreted the test according to package-insert instructions. In multivariate analysis, only older age was significantly associated with false-positive results (adjusted odds ratio = 4.5, 95% CI: 1.2-25.7). In the incidence study, all valid oral-fluid and whole-blood results from 2,268 clients were concordant and no false-positive results occurred (100% specificity). CONCLUSIONS/SIGNIFICANCE: The field investigation did not identify a cause for the increase in false-positive oral-fluid results, and the incidence study detected no false-positive results. The findings suggest this was an isolated cluster; the test's overall performance was as specified by the manufacturer.
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Sorodiagnóstico da AIDS/métodos , Reações Falso-Positivas , Infecções por HIV/diagnóstico , Soropositividade para HIV/diagnóstico , HIV-1/imunologia , Kit de Reagentes para Diagnóstico/normas , Adulto , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/imunologia , Humanos , Masculino , Vigilância de Produtos Comercializados/métodos , Fatores de RiscoRESUMO
An assay capable of simultaneously measuring both general toxicity and more subtle genotoxicity, in aqueous environmental samples, is described. The assay uses eukaryotic (yeast) cells, genetically modified to express a green fluorescent protein (GFP) whenever DNA damage, as a result of exposure to genotoxic agents, is repaired. A measure of the reduction in cell proliferation is used to characterise general toxicity producing familiar EC(50) and LOEC data. The assay protocol has been developed for proposed use in the field and hence employs dedicated, portable instrumentation, the development of which is described. A range of environmentally relevant substances has been evaluated using the assay, including solutions of metal ions, solvents and pesticides. Preliminary data comparing the yeast assay's response to that of a standard Daphnia test in the analysis of the toxicity of 34 varied industrial waste effluents are also presented. The sensitivity to a wide range of substances and effluents suggests the assay should be useful for environmental toxicity monitoring.