Right Dorsolateral Frontal Lobe N-Acetyl Aspartate and Myoinositol Concentration Estimation in Type 2 Diabetes with Magnetic Resonance Spectroscopy.

PubMed

Nagothu, Rajani Santhakumari; Reddy, Yogananda Indla; Rajagopalan, Archana; Varma, Ravi

2015-07-01

Chronic hyperglycaemia in type 2 diabetes, effects the central nervous system by altering the concentrations of brain metabolites like N-acetyl aspartate (NAA) and myoinositol (mI), which are indicators of neuronal integrity and glial cell damage respectively. Dorsolateral frontal lobe is associated with aspects of cognition especially right frontal lobe is involved in episodic memory retrieval, ninety percent of the diabetic cases are type 2 in nature globally and yoga is very effective in stabilizing the brain metabolites by bringing the blood glucose levels to near or within the physiological range in type 2 diabetes. The aim of the study was to observe the effects of yogasana and pranayama on glycosilated haemoglobin (HbA1c) levels and right dorsolateral frontal cortical NAA and mI concentration in type 2 diabetic subjects. It's a case control study. Sixty eight type 2 diabetic subjects of both the sex, aged between 35-65 years are included in the study, subjects are divided in to test and control group 34 each. Test group subjects did the yogasana and pranayama for a period of 6 months, 6 days in a week, 45-60 minutes daily under the supervision of a qualified yoga teacher. Control group subjects are not on any specific exercise regimen. Both the group subjects are taking oral hypoglycaemic agents. HbA1c levels are measured using the Bio-Rad D-10™ haemoglobin A1c program and Magnetic Resonance Spectroscopy (MRS) is used in assessing the metabolite concentrations. Analysis of data was done by using unpaired t-test. P-value for HbA1c level is <0.001, which is highly significant statistically. P-value for NAA was < 0.02 and for myoinositol was < 0.01, which are statistically significant. HbA1c levels in control and test group subjects are 7.7 ± 1.84 and 6.02 ± 0.46 respectively. NAA concentrations in the right dorsolateral frontal lobe of control and test group are 1.44 ± 0.15 and 1.54 ± 0.19 respectively. The mI concentrations in the right dorsolateral frontal lobe of control and test group are 0.61 ± 0.22 and 0.47 ± 0.24 respectively. Yogasana and pranayama minimized the neuronal and glial cellular damage in test group, which is evident by minimal changes in right dorsolateral frontal lobe NAA and mI levels in type 2 diabetic subjects.

Noninvasive and Painless Urine Glucose Detection by Using Computer-based Polarimeter

NASA Astrophysics Data System (ADS)

Sutrisno; Laksono, Y. A.; Hidayat, N.

2017-05-01

Diabetes kills millions of people worldwide each year. It challenges us as researchers to give contribution in early diagnosis to ensure a healthy life. As a matter of fact, common glucose testing devices that have been widely used so far are, at least, glucose meter and urine glucose test strip. The glucose meter ordinarily requires blood taken from patient’s finger. The glucose test strip uses patient’s urine but records unspecific urine glucose level, since the strip only provides the glucose level in some particular ranges. Instead of detecting the glucose level in blood and using the non-specific technique, a noninvasive and painless technique that can detect glucose level accurately will provide a more feasible approach for diabetes diagnosis. The noninvasive and painless urine glucose level monitoring by means of computer-based polarimeter is presented in this paper. The instrument consisted of a power source, a sample box, a light sensor, a polarizer, an analyzer, an analog to digital converter (ADC), and a computer. The concentration of urine glucose concentration was evaluated from the curve of the change in detected optical rotation angle and output potential by the computer-based polarimeter. Statistical analyses by means of Gaussian fitting and linear regression were applied to investigate the rotation angle and urine glucose concentration, respectively. From our experiment, the urine glucose level, measured by glucose test strips, of the normal patient was 100 mg/dl, and the diabetic patient was 500 mg/dl. Our polarimeter even read more precise values for the urine glucose concentrations of those normal and diabetic of the same patients, i.e. 50.61 mg/dl and 502.41 mg/dl, respectively. In other words, the results showed that our polarimeter was able to quantitatively measure the urine glucose level more accurate than urine glucose test strips. Hence, this computer-based polarimeter could be used as an alternative for early detection of urine glucose with noninvasive and painless characteristics.

Head-space, small-chamber and in-vehicle tests for volatile organic compounds (VOCs) emitted from air fresheners for the Korean market.

PubMed

Jo, Wan-Kuen; Lee, Jong-Hyo; Kim, Mo-Keun

2008-02-01

The present study investigated the emission characteristics of gel-type air fresheners (AFs), using head-space, small-chamber, and in-vehicle tests. Five toxic or hazardous analytes were found in the headspace phase of AFs (toluene, benzene, ethyl benzene, and m,p-xylene) at a frequency of more than 50%. Limonene and linalool, which are known to be unsaturated ozone-reactive VOCs, were detected at a frequency of 58 and 35%, respectively. The empirical model fitted well with the time-series concentrations in the chamber, thereby suggesting that the empirical model was suitable for testing emissions. Limonene exhibited the highest emission rate, followed by m,p-xylene, toluene, ethyl benzene, and benzene. For most target VOCs, higher air change per hour (ACH) levels exhibited increased emission rates. In contrast, higher ACH levels resulted in lower chamber concentrations. The mean concentration of limonene was significantly higher in passenger cars with an AF than without. For other target compounds, there were no significant differences between the two conditions tested. Consequently, it was suggested that unlike limonene, the emission strength for aromatic compounds identified in the chamber tests was not strong enough to elevate in-vehicle levels.

Toxicity profiles and solvent-toxicant interference in the planarian Schmidtea mediterranea after dimethylsulfoxide (DMSO) exposure.

PubMed

Stevens, An-Sofie; Pirotte, Nicky; Plusquin, Michelle; Willems, Maxime; Neyens, Thomas; Artois, Tom; Smeets, Karen

2015-03-01

To investigate hydrophobic test compounds in toxicological studies, solvents like dimethylsulfoxide (DMSO) are inevitable. However, using these solvents, the interpretation of test compound-induced responses can be biased. DMSO concentration guidelines are available, but are mostly based on acute exposures involving one specific toxicity endpoint. Hence, to avoid solvent-toxicant interference, we use multiple chronic test endpoints for additional interpretation of DMSO concentrations and propose a statistical model to assess possible synergistic, antagonistic or additive effects of test compounds and their solvents. In this study, the effects of both short- (1 day) and long-term (2 weeks) exposures to low DMSO concentrations (up to 1000 µl l(-1) ) were studied in the planarian Schmidtea mediterranea. We measured different biological levels in both fully developed and developing animals. In a long-term exposure set-up, a concentration of 500 µl l(-1) DMSO interfered with processes on different biological levels, e.g. behaviour, stem cell proliferation and gene expression profiles. After short exposure times, 500 µl l(-1) DMSO only affected motility, whereas the most significant changes on different parameters were observed at a concentration of 1000 µl l(-1) DMSO. As small sensitivity differences exist between biological levels and developmental stages, we advise the use of this solvent in concentrations below 500 µl l(-1) in this organism. In the second part of our study, we propose a statistical approach to account for solvent-toxicant interactions and discuss full-scale solvent toxicity studies. In conclusion, we reassessed DMSO concentration limits for different experimental endpoints in the planarian S. mediterranea. Copyright © 2014 John Wiley & Sons, Ltd.

Impact of fetal and childhood mercury exposure on immune status in children.

PubMed

Hui, Lai Ling; Chan, Michael Ho Ming; Lam, Hugh Simon; Chan, Peggy Hiu Ying; Kwok, Ka Ming; Chan, Iris Hiu Shuen; Li, Albert Martin; Fok, Tai Fai

2016-01-01

Mercury exposure have been shown to affect immune status in animals as reflected by cytokine expression. It is unclear whether low levels of exposure during fetal and/or childhood periods could impact on immune status in humans. To test the hypothesis that fetal and childhood mercury exposure is associated with childhood cytokine profiles and to investigate whether childhood selenium levels interact with any of the associations found. Children were recruited from a previously established birth cohort between the ages of 6-9 years for assessment and measurement of blood mercury, selenium and cytokine profile (interleukin (IL)-4, IL-6, IL-8, IL-10, IL-13 and TNF-alpha). Multivariable linear regression models were used to assess the adjusted association of cord blood mercury concentration and current mercury concentrations with levels of the cytokine levels. We tested whether the association with current mercury level varied by current selenium level and cord blood mercury level. IL-10 was negatively associated with current blood mercury concentration. The effect was greatest in cases with low cord blood mercury and low current selenium concentrations. None of the other cytokine levels were associated with either cord blood or current blood mercury concentrations, except that cord blood mercury was negatively associated with IL-6. Childhood mercury exposure was negatively associated with childhood IL-10 levels. It is postulated that while selenium is protective, low levels of fetal mercury exposure may increase the degree of this negative association during childhood. Further studies into the clinical significance of these findings are required. Copyright © 2015 Elsevier Inc. All rights reserved.

[Effect of different oxygen concentrations on biological properties of bone marrow hematopoietic stem cells of mice].

PubMed

Ma, Yi-Ran; Ren, Si-Hua; He, Yu-Xin; Wang, Lin-Lin; Jin, Li; Hao, Yi-Wen

2012-10-01

This study purposed to investigate the effects of different oxygen concentrations and reactive oxygen species (ROS) on the biological characteristics of hematopoietic stem cells (HSC) and their possible mechanisms through simulating oxygen environment to which the peripheral blood HSC are subjected in peripheral blood HSCT. The proliferation ability, cell cycle, directed differentiation ability, ROS level and hematopoietic reconstitution ability of Lin(-)c-kit(+)Sca-1(+) BMHSC were detected by using in vitro amplification test, directional differentiation test, cell cycle analysis, ROS assay and transplantation of Lin(-)c-kit(+)Sca-1(+) HSC from sublethally irradiated mice respectively. The results showed that oxygen concentrations lower than normal oxygen concentration, especially in hypoxic oxygen environment, could reduce ROS generation and amplify more primitive CD34(+)AC133(+) HSC and active CD34(+) HSC, and maintain more stem cells in the G(0)/G(1) phase, which is more helpful to the growth of CFU-S and viability of mice. At the same time, BMHSC exposed to normal oxygen level or inconstant and greatly changed oxygen concentrations could produce a high level of ROS, and the above-mentioned features and functional indicators are relatively low. It is concluded that ROS levels of HSC in BMHSCT are closely related with the oxygen concentration surrounding the cells and its stability. Low oxygen concentration and antioxidant intervention are helpful to transplantation of BMHSC.

Defining the baseline for inhibition concentration calculations for hormetic hazards.

PubMed

Bailer, A J; Oris, J T

2000-01-01

The use of endpoint estimates based on modeling inhibition of test organism response relative to a baseline response is an important tool in the testing and evaluation of aquatic hazards. In the presence of a hormetic hazard, the definition of the baseline response is not clear because non-zero levels of the hazard stimulate an enhanced response prior to inhibition. In the present study, the methodology and implications of how one defines a baseline response for inhibition concentration estimation in aquatic toxicity tests was evaluated. Three possible baselines were considered: the control response level; the pooling of responses, including controls and all concentration conditions with responses enhanced relative to controls; and, finally, the maximal response. The statistical methods associated with estimating inhibition relative to the first two baseline definitions were described and a method for estimating inhibition relative to the third baseline definition was derived. These methods were illustrated with data from a standard aquatic zooplankton reproductive toxicity test in which the number of young produced in three broods of a cladoceran exposed to effluent was modeled as a function of effluent concentration. Copyright 2000 John Wiley & Sons, Ltd.

Vehicle occupants' exposure to aromatic volatile organic compounds while commuting on an urban-suburban route in Korea.

PubMed

Jo, W K; Choi, S J

1996-08-01

This study identified in-auto and in-bus exposures to six selected aromatic volatile organic compounds (VOCs) for commutes on an urban-suburban route in Korea. A bus-service route was selected to include three segments of Taegu and one suburban segment (Hayang) to satisfy the criteria specified for this study. This study indicates that motor vehicle exhaust and evaporative emissions are major sources of both auto and bus occupants' exposures to aromatic VOCs in both Taegu and Hayang. A nonparametric statistical test (Wilcoxon test) showed that in-auto benzene levels were significantly different from in-bus benzene levels for both urban-segment and suburban-segment commutes. The test also showed that the benzene-level difference between urban-segment and suburban-segment commutes was significant for both autos and buses. An F-test showed the same statistical results for the comparison of the summed in-vehicle concentration of the six target VOCs (benzene, toluene, ethylbenzene, and o,m,p-xylenes) as those for the comparison of the in-vehicle benzene concentration. On the other hand, the in-vehicle benzene level only and the sum were not significantly different among the three urban-segment commutes and between the morning and evening commutes. The in-auto VOC concentrations were intermediate between the results for the Los Angeles and Boston. The in-bus VOC concentrations were about one-tenth of the Taipei, Taiwan results.

Preliminary measurement of gas concentrations of perfluropropane using an analytical weighing balance.

PubMed

Clarkson, Douglas McG; Manna, Avinish; Hero, Mark

2014-02-01

We describe the use of an analytical weighing balance of measurement accuracy 0.00001g for determination of concentrations of perfluropropane (C3F8) gas used in ophthalmic surgical vitrectomy procedures. A range of test eyes corresponding to an eye volume of 6.1ml were constructed using 27 gauge needle exit ducts and separately 20 gauge (straight) and 23 gauge (angled) entrance ports. This method allowed determination of concentration levels in the sample preparation syringe and also levels in test eyes. It was determined that a key factor influencing gas concentrations accuracy related to the method of gas fill and the value of dead space of the gas preparation/delivery system and with a significant contribution arising from the use of the particle filter. The weighing balance technique was identified as an appropriate technique for estimation of gas concentrations. Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.

Dynamics of carbon dioxide concentrations in the air and its effect on the cognitive ability of school students

NASA Astrophysics Data System (ADS)

Sidorin, D. I.

2015-12-01

The carbon dioxide (CO2) production intensity by a secondary school student is studied using a nondispersive infrared CO2 logger for different conditions: relaxation, mental stress, and physical stress. CO2 production measured for mental stress is 24% higher than that for relaxation, while CO2 production for physical stress is more than 2.5 times higher than relaxation levels. Dynamics of CO2 concentration in the classroom air is measured for a typical school building. It is shown that even when the classroom is ventilated between classes, CO2 concentration exceeds 2100 parts per million (ppm), which is significantly higher than the recommended limits defined in developed countries. The ability of seventh-grade school students to perform tasks requiring mental concentration is tested under different CO2 concentration conditions (below 1000 ppm and above 2000 ppm). Five-letter word anagrams are used as test tasks. Statistical analysis of the test results revealed a significant reduction in the number of provided correct answers and an increase in the number of errors when CO2 levels exceeded 2000 ppm.

Characteristics of cabin air quality in school buses in Central Texas

NASA Astrophysics Data System (ADS)

Rim, Donghyun; Siegel, Jeffrey; Spinhirne, Jarett; Webb, Alba; McDonald-Buller, Elena

This study assessed in-cabin concentrations of diesel-associated air pollutants in six school buses with diesel engines during a typical route in suburban Austin, Texas. Air exchange rates measured by SF 6 decay were 2.60-4.55 h -1. In-cabin concentrations of all pollutants measured exhibited substantial variability across the range of tests even between buses of similar age, mileage, and engine type. In-cabin NO x concentrations ranged from 44.7 to 148 ppb and were 1.3-10 times higher than roadway NO x concentrations. Mean in-cabin PM 2.5 concentrations were 7-20 μg m -3 and were generally lower than roadway levels. In-cabin concentrations exhibited higher variability during cruising mode than frequent stops. Mean in-cabin ultrafine PM number concentrations were 6100-32,000 particles cm -3 and were generally lower than roadway levels. Comparison of median concentrations indicated that in-cabin ultrafine PM number concentrations were higher than or approximately the same as the roadway concentrations, which implied that, by excluding the bias caused by local traffic, ultrafine PM levels were higher in the bus cabin than outside of the bus. Cabin pollutant concentrations on three buses were measured prior to and following the phased installation of a Donaldson Spiracle Crankcase Filtration System and a Diesel Oxidation Catalyst. Following installation of the Spiracle, the Diesel Oxidation Catalyst provided negligible or small additional reductions of in-cabin pollutant levels. In-cabin concentration decreases with the Spiracle alone ranged from 24 to 37% for NO x and 26 to 62% and 6.6 to 43% for PM 2.5 and ultrafine PM, respectively. Comparison of the ranges of PM 2.5 and ultrafine PM variations between repetitive tests suggested that retrofit installation could not always be conclusively linked to the decrease of pollutant levels in the bus cabin.

Low pCO2 Air-Polarized CO2 Concentrator Development

NASA Technical Reports Server (NTRS)

Schubert, Franz H.

1997-01-01

Life Systems completed a Ground-based Space Station Experiment Development Study Program which verifies through testing the performance and applicability of the electrochemical Air-Polarized Carbon Dioxide Concentrator (APC) process technology for space missions requiring low (i.e., less than 3 mm Hg) CO2 partial pressure (pCO2) in the cabin atmosphere. Required test hardware was developed and testing was accomplished at an approximate one-person capacity CO2 removal level. Initially, two five-cell electrochemical modules using flight-like 0.5 sq ft cell hardware were tested individually, following by their testing at the integrated APC system level. Testing verified previously projected performance and established a database for sizing of APC systems. A four person capacity APC system was sized and compared with four candidate CO2 removal systems. At its weight of 252 lb, a volume of 7 cu ft and a power consumption of 566 W while operating at 2.2 mm Hg pCO2, the APC was surpassed only by an Electrochemical Depolarized CO2 Concentrator (EDC) (operating with H2), when compared on a total equivalent basis.

Toxicity of DEGDN (Diethyleneglycol Dinitrate), Synthetic-HC Smoke Combustion Products, Solvent Yellow 33 and Solvent Green 3 to Freshwater Aquatic Organisms. Phase 2

DTIC Science & Technology

1987-01-15

algicidal effect on the * alga. LC50 values for the rainbow trout and the water flea were 2.2% and 9.3% of the stock solution, respectively. Additional...significantly from the initial inoculum level. " Algicidal concentration. This is the lowest concentration tested which causes an apparent algistatic...86.9 - 335.5 mg/L). The minimum algicidal concentration was greater than 542.4 mg/L, the highest concentration tested. When algal cultures from this

Carbon Concentration and Carbon-to-Nitrogen Ratio Influence Submerged-Culture Conidiation by the Potential Bioherbicide Colletotrichum truncatum NRRL 13737

PubMed Central

Jackson, Mark A.; Bothast, Rodney J.

1990-01-01

We assessed the influence of various carbon concentrations and carbon-to-nitrogen (C:N) ratios on Colletotrichum truncatum NRRL 13737 conidium formation in submerged cultures grown in a basal salts medium containing various amounts of glucose and Casamino Acids. Under the nutritional conditions tested, the highest conidium concentrations were produced in media with carbon concentrations of 4.0 to 15.3 g/liter. High carbon concentrations (20.4 to 40.8 g/liter) inhibited sporulation and enhanced the formation of microsclerotiumlike hyphal masses. At all the carbon concentrations tested, a culture grown in a medium with a C:N ratio of 15:1 produced more conidia than cultures grown in media with C:N ratios of 40:1 or 5:1. While glucose exhaustion was often coincident with conidium formation, cultures containing residual glucose sporulated and those with high carbon concentrations (>25 g/liter) exhausted glucose without sporulation. Nitrogen source studies showed that the levels of C. truncatum NRRL 13737 conidiation were similar for all protein hydrolysates tested. Reduced conidiation occurred when amino acid and inorganic nitrogen sources were used. Of the nine carbon sources evaluated, acetate as the sole carbon source resulted in the lowest level of sporulation. Images PMID:16348348

Toxicity of manganese to Ceriodaphnia dubia and Hyalella azteca

USGS Publications Warehouse

Lasier, P.J.; Winger, P.V.; Bogenrieder, K.J.

2000-01-01

Manganese is a toxic element frequently overlooked when assessing toxicity of effluents, sediments and pore waters. Manganese can be present at toxic levels in anoxic solutions due to its increased solubility under chemically-reducing conditions, and it can remain at those levels for days in aerated test waters due to slow precipitation kinetics. Ceriodaphnia dubia and Hyalella azteca are freshwater organisms often used for toxicity testing and recommended for assessments of effluents and pore waters. Lethal and reproductive-inhibition concentrations of Mn were determined for C. dubia in acute 48h tests and chronic 3-brood tests using animals <24 h old and between 24 and 48 h old. Sensitivity of H. azteca was determined with 7d old animals in acute 96h tests. Tests were run at three levels of water hardness to assess the amelioratory effect, which was often significant. Manganese concentrations were measured analytically at test initiation and after 96 h for calculations of toxicity endpoints and determinations of Mn precipitation during the tests. Minimal amounts of Mn (below 3%) precipitated within 96 h. LC50s determined for H. azteca progressively increased from 3.0 to 8.6 to 13.7 mg Mn/L in soft, moderately-hard and hard waters, respectively. The tolerance of C. dubia to Mn was not significantly different between moderately-hard and hard waters, but was significantly lower in soft water. There was no significant difference in Mn sensitivity between the ages of C. dubia tested. Acute LC50 values for C. dubia averaged 6.2, 14.5 and 15.2 mg Mn/L and chronic IC50 values averaged 3.9, 8.5 and 11.5 mg Mn/L for soft, moderately-hard and hard waters, respectively. Manganese toxicity should be considered when assessing solutions with concentrations near these levels.

Comparison of in-house biotin-avidin tetanus IgG enzyme-linked-immunosorbent assay (ELISA) with gold standard in vivo mouse neutralization test for the detection of low level antibodies.

PubMed

Sonmez, Cemile; Coplu, Nilay; Gozalan, Aysegul; Akin, Lutfu; Esen, Berrin

2017-06-01

Detection of anti-tetanus antibody levels is necessary for both determination of the immune status of individuals and also for planning preventive measures. ELISA is the preferred test among in vitro tests however it can be affected by the cross reacting antibodies. A previously developed in-house ELISA test was found not reliable for the antibody levels ≤1.0IU/ml. A new method was developed to detect low antibody levels correctly. The aim of the present study was to compare the results of the newly developed in-house biotin-avidin tetanus IgG ELISA test with the in vivo mouse neutralization test, for the antibody levels ≤1.0IU/ml. A total of 54 serum samples with the antibody levels of three different levels, =0.01IU/ml, 0.01-0.1IU/ml, 0.1-1IU/ml, which were detected by in vivo mouse neutralization test were studied by the newly developed in-house biotin-avidin tetanus IgG ELISA test. Test was validated by using five different concentrations (0.01IU/ml, 0.06IU/ml, 0.2IU/ml, 0.5IU/ml, 1.0IU/ml). A statistically significant correlation (r 2 =0.9967 p=0,001) between in vivo mouse neutralization test and in-house biotin-avidin tetanus IgG ELISA test, was observed. For the tested concentrations intra-assay, inter-assay, accuracy, sensitivity, specificity and coefficients of variations were determined as ≤15%. In-house biotin-avidin tetanus IgG ELISA test can be an alternative method to in vivo mouse neutralization method for the detection of levels ≤1.0IU/ml. By using in-house biotin-avidin tetanus IgG ELISA test, individuals with non protective levels, will be reliably detected. Copyright © 2017. Published by Elsevier B.V.

Assessment of combinations of antiandrogenic compounds vinclozolin and flutamide in a yeast based reporter assay.

PubMed

Kolle, Susanne N; Melching-Kollmuss, Stephanie; Krennrich, Gerhard; Landsiedel, Robert; van Ravenzwaay, Bennard

2011-08-01

Humans are exposed to a combination of various substances such as cosmetic ingredients, drugs, biocides, pesticides and natural-occurring substances in food. The combined toxicological effects of two or more substances can simply be additive on the basis of response-addition, or it can be greater (synergistic) or smaller (antagonistic) than this. The need to assess combined effects of compounds with endocrine activity is currently discussed for regulatory risk assessment. We have used a well described yeast based androgen receptor transactivation assay YAS to assess the combinatorial effects of vinclozolin and flutamide; both mediating antiandrogenicity via the androgen receptor. Both vinclozolin and flutamide were antiandrogens of similar potency in the YAS assay. In the concentration range tested the two antiandrogens vinclozolin and flutamide did not act synergistically. Concentration additivity was observed in the linear, non-receptor-saturated concentration range. At high concentrations of one of the two substances tested the contribution of the second at lower concentration levels was less than additive. The combined response of both compounds at high concentration levels was also less than additive (saturation effect). At concentration levels which did not elicit a response of the individual compounds, the combination of these compounds also did not elicit a response. Copyright © 2011 Elsevier Inc. All rights reserved.

Early pregnancy fasting plasma glucose and lipid concentrations in pregnancy and association to offspring size: a retrospective cohort study.

PubMed

Liu, Bin; Geng, Huizhen; Yang, Juan; Zhang, Ying; Deng, Langhui; Chen, Weiqing; Wang, Zilian

2016-03-17

Hyperlipidemia and high fasting plasma glucose levels at the first prenatal visit (First Visit FPG) are both related to gestational diabetes mellitus, maternal obesity/overweight and fetal overgrowth. The purpose of the present study is to investigate the correlation between First Visit FPG and lipid concentrations, and their potential association with offspring size at delivery. Pregnant women that received regular prenatal care and delivered in our center in 2013 were recruited for the study. Fasting plasma glucose levels were tested at the first prenatal visit (First Visit FPG) and prior to delivery (Before Delivery FPG). HbA1c and lipid profiles were examined at the time of OGTT test. Maternal and neonatal clinical data were collected for analysis. Data was analyzed by independent sample t test, Pearson correlation, and Chi-square test, followed by partial correlation and multiple linear regression analyses to confirm association. Statistical significance level was α =0.05. Analyses were based on 1546 mother-baby pairs. First Visit FPG was not correlated with any lipid parameters after adjusting for maternal pregravid BMI, maternal age and gestational age at First Visit FPG. HbA1c was positively correlated with triglyceride and Apolipoprotein B in the whole cohort and in the NGT group after adjusting for maternal age and maternal BMI at OGTT test. Multiple linear regression analyses showed neonatal birth weight, head circumference and shoulder circumference were all associated with First Visit FPG and triglyceride levels. Fasting plasma glucose at first prenatal visit is not associated with lipid concentrations in mid-pregnancy, but may influence fetal growth together with triglyceride concentration.

Milk urea testing as a tool to monitor reproductive performance in Ontario dairy herds.

PubMed

Godden, S M; Kelton, D F; Lissemore, K D; Walton, J S; Leslie, K E; Lumsden, J H

2001-06-01

Dairy herd improvement test-day data, including milk urea concentrations measured using infrared test method, were collected from 60 commercial Ontario Holstein dairy herds for a 13-mo period between December 1, 1995, and December 31, 1996. The objective of the study was to describe, at the cow and the group level, the relationship between DHI milk urea concentrations and reproductive performance in commercial dairy herds. When interpreted at the cow level, there was no association between milk urea and the risk for pregnancy from an insemination occurring within the 45-d period preceding test day. However, a negative curvilinear relationship existed between milk urea and the risk for pregnancy from a first, second, or third insemination event occurring within the 45-d period following test day, with the odds for pregnancy being highest when the milk urea on the test day preceding the insemination was either below 4.5 mmol/L or greater than 6.49 mmol/L, compared with a concentration between 4.5 and 6.49 mmol/L. When interpreted at the group level, there was no association between group mean milk urea for cows between 50 and 180 DIM, and the group conception rate for cows receiving a first, second, or third insemination event in the 45-d period either preceding or following test day. Thus, while DHI milk urea measurements may be useful as a management tool to improve the efficiency of production or reduce nitrogen excretion, through helping to optimize the efficiency of protein utilization, they may have limited utility as a monitoring or diagnostic tool for reproductive performance. The results of this study suggest that good fertility may be achieved across a broad range of milk urea concentrations.

Cadmium Alters the Concentration of Fatty Acids in THP-1 Macrophages.

PubMed

Olszowski, Tomasz; Gutowska, Izabela; Baranowska-Bosiacka, Irena; Łukomska, Agnieszka; Drozd, Arleta; Chlubek, Dariusz

2018-03-01

Fatty acid composition of human immune cells influences their function. The aim of this study was to evaluate the effects of known toxicant and immunomodulator, cadmium, at low concentrations on levels of selected fatty acids (FAs) in THP-1 macrophages. The differentiation of THP-1 monocytes into macrophages was achieved by administration of phorbol myristate acetate. Macrophages were incubated with various cadmium chloride (CdCl 2 ) solutions for 48 h at final concentrations of 5 nM, 20 nM, 200 nM, and 2 μM CdCl 2 . Fatty acids were extracted from samples according to the Folch method. The fatty acid levels were determined using gas chromatography. The following fatty acids were analyzed: long-chain saturated fatty acids (SFAs) palmitic acid and stearic acid, very long-chain saturated fatty acid (VLSFA) arachidic acid, monounsaturated fatty acids (MUFAs) palmitoleic acid, oleic acid and vaccenic acid, and n-6 polyunsaturated fatty acids (PUFAs) linoleic acid and arachidonic acid. Treatment of macrophages with very low concentrations of cadmium (5-200 nM) resulted in significant reduction in the levels of arachidic, palmitoleic, oleic, vaccenic, and linoleic acids and significant increase in arachidonic acid levels (following exposure to 5 nM Cd), without significant reduction of palmitic and stearic acid levels. Treatment of macrophages with the highest tested cadmium concentration (2 μM) produced significant reduction in the levels of all examined FAs: SFAs, VLSFA, MUFAs, and PUFAs. In conclusion, cadmium at tested concentrations caused significant alterations in THP-1 macrophage fatty acid levels, disrupting their composition, which might dysregulate fatty acid/lipid metabolism thus affecting macrophage behavior and inflammatory state.

Salivary testosterone levels are unrelated to handedness or cerebral lateralization for language.

PubMed

Papadatou-Pastou, Marietta; Martin, Maryanne; Mohr, Christine

2017-03-01

Behavioural and cerebral lateralization are thought to be controlled, at least in part, by prenatal testosterone (T) levels, explaining why sex differences are found in both laterality traits. The present study investigated hormonal effects on laterality using adult salivary T levels, to explore the adequacy of competing theories: the Geschwind, Behan and Galaburda, the callosal, and the sexual differentiation hypotheses. Sixty participants (15 right-handers and 15 left-handers of each sex) participated. Behavioural lateralization was studied by means of hand preference tests (i.e., the Edinburgh Handedness Inventory and the Quantification of Hand Preference test) and a hand skill test (i.e., the Peg-Moving test) whereas cerebral lateralization for language was studied using the Consonant-Vowel Dichotic Listening test and the Visual Half-Field Lexical Decision test. Salivary T and cortisol (C) concentrations were measured by luminescence immunoassay. Canonical correlations did not reveal significant relationships between T levels and measures of hand preference, hand skill, or language laterality. Thus, our findings add to the growing literature showing no relationship between T concentrations with behavioural or cerebral lateralization. It is claimed that prenatal T is not a major determinant of individual variability in either behavioural or cerebral lateralization.

Role of cellular antioxidants (glutathione and ascorbic acid) in the growth and development of wild carrot suspension cultures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Earnshaw, B.A.

1986-01-01

Determinations of endogenous glutathione (GSH), glutathione disulfide (GSSG), ascorbic acid (AA) and dehydroascorbic acid (DHA) in proliferating and developing wild carrot cultures showed that lower levels of GSH and AA were associated with developing cultures. The GSSG and DHA levels did not account for the changes in the levels of antioxidants between proliferating and developing cultures. Studies were designed to test an observed auxin (2,4-Dichlorophenoxyacetic acid, 2,4-D)-antioxidant association. Two fractions (embryo and less developed) were obtained by screening developed cultures which were previously grown in the presence of /sup 14/C-2, 4-D. The embryo fraction had a lower concentration of /supmore » 14/C than the less developed fraction, supporting the association, since the two fractions showed this relationship with respect to GSH and AA concentrations. Determinations of GSH and AA levels of cells grown in various concentrations of 2,4-D showed the association, decreases in the 2,4-D concentration correlated with decreases in the GSH and AA concentrations. The existence of a respiratory pathway involving GSSG reductase, DHA reductase, and AA oxidase was investigated to test whether inhibition of AA oxidase by 2,4-D could explain the auxin-antioxidant association; however, AA oxidase activity was not detected.« less

Decreasing airborne contamination levels in high-risk hospital areas using a novel mobile air-treatment unit.

PubMed

Bergeron, V; Reboux, G; Poirot, J L; Laudinet, N

2007-10-01

To evaluate the performance of a new mobile air-treatment unit that uses nonthermal-plasma reactors for lowering the airborne bioburden in critical hospital environments and reducing the risk of nosocomial infection due to opportunistic airborne pathogens, such as Aspergillus fumigatus. Tests were conducted in 2 different high-risk hospital areas: an operating room under simulated conditions and rooms hosting patients in a pediatric hematology ward. Operating room testing provided performance evaluations of removal rates for airborne contamination (ie, particles larger than 0.5 microm) and overall lowering of the airborne bioburden (ie, colony-forming units of total mesophilic flora and fungal flora per cubic meter of air). In the hematology service, opportunistic and nonpathogenic airborne fungal levels in a patient's room equipped with an air-treatment unit were compared to those in a control room. In an operating room with a volume of 118 m(3), the time required to lower the concentration of airborne particles larger than 0.5 microm by 90% was decreased from 12 minutes with the existing high-efficiency particulate air filtration system to less than 2 minutes with the units tested, with a 2-log decrease in the steady-state levels of such particles (P<.01). Concurrently, total airborne mesophilic flora concentrations dropped by a factor of 2, and the concentrations of fungal species were reduced to undetectable levels (P<.01). The 12-day test period in the hematology ward revealed a significant reduction in airborne fungus levels (P<.01), with average reductions of 75% for opportunistic species and 82% for nonpathogenic species. Our data indicate that the mobile, nonthermal-plasma air treatment unit tested in this study can rapidly reduce the levels of airborne particles and significantly lower the airborne bioburden in high-risk hospital environments.

WSN based indoor air quality monitoring in classrooms

NASA Astrophysics Data System (ADS)

Wang, S. K.; Chew, S. P.; Jusoh, M. T.; Khairunissa, A.; Leong, K. Y.; Azid, A. A.

2017-03-01

Indoor air quality monitoring is essential as the human health is directly affected by indoor air quality. This paper presents the investigations of the impact of undergraduate students' concentration during lecture due to the indoor air quality in classroom. Three environmental parameters such as temperature, relative humidity and concentration of carbon dioxide are measured using wireless sensor network based air quality monitoring system. This simple yet reliable system is incorporated with DHT-11 and MG-811 sensors. Two classrooms were selected to install the monitoring system. The level of indoor air quality were measured and students' concentration was assessed using intelligent test during normal lecturing section. The test showed significant correlation between the collected environmental parameters and the students' level of performances in their study.

Optimizing bulk milk dioxin monitoring based on costs and effectiveness.

PubMed

Lascano-Alcoser, V H; Velthuis, A G J; van der Fels-Klerx, H J; Hoogenboom, L A P; Oude Lansink, A G J M

2013-07-01

Dioxins are environmental pollutants, potentially present in milk products, which have negative consequences for human health and for the firms and farms involved in the dairy chain. Dioxin monitoring in feed and food has been implemented to detect their presence and estimate their levels in food chains. However, the costs and effectiveness of such programs have not been evaluated. In this study, the costs and effectiveness of bulk milk dioxin monitoring in milk trucks were estimated to optimize the sampling and pooling monitoring strategies aimed at detecting at least 1 contaminated dairy farm out of 20,000 at a target dioxin concentration level. Incidents of different proportions, in terms of the number of contaminated farms, and concentrations were simulated. A combined testing strategy, consisting of screening and confirmatory methods, was assumed as well as testing of pooled samples. Two optimization models were built using linear programming. The first model aimed to minimize monitoring costs subject to a minimum required effectiveness of finding an incident, whereas the second model aimed to maximize the effectiveness for a given monitoring budget. Our results show that a high level of effectiveness is possible, but at high costs. Given specific assumptions, monitoring with 95% effectiveness to detect an incident of 1 contaminated farm at a dioxin concentration of 2 pg of toxic equivalents/g of fat [European Commission's (EC) action level] costs €2.6 million per month. At the same level of effectiveness, a 73% cost reduction is possible when aiming to detect an incident where 2 farms are contaminated at a dioxin concentration of 3 pg of toxic equivalents/g of fat (EC maximum level). With a fixed budget of €40,000 per month, the probability of detecting an incident with a single contaminated farm at a dioxin concentration equal to the EC action level is 4.4%. This probability almost doubled (8.0%) when aiming to detect the same incident but with a dioxin concentration equal to the EC maximum level. This study shows that the effectiveness of finding an incident depends not only on the ratio at which, for testing, collected truck samples are mixed into a pooled sample (aiming at detecting certain concentration), but also the number of collected truck samples. In conclusion, the optimal cost-effective monitoring depends on the number of contaminated farms and the concentration aimed at detection. The models and study results offer quantitative support to risk managers of food industries and food safety authorities. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

State test-anxiety, selective attention and concentration in university students.

PubMed

Fernández-Castillo, Antonio; Caurcel, María J

2015-08-01

The principal aim of this study was to assess the level of selective attention and mental concentration before exams in a sample of university students and to determine a possible relationship between anxiety and reduction of levels of attention in this circumstance. A total of 403 university students, 176 men and 227 women, aged from 18 to 46 years, participated in the study. Of them, 169 were first-year undergraduates, 118 were second to fourth-year undergraduates and 116 were postgraduate Master's degree students. All of them completed the Spanish version of the Spielberger State-Anxiety Inventory and the D2 Attention Test just before taking an exam. Our results showed that participants with lower levels of anxiety had higher levels of selective attention and mental concentration before the exam. These results specifically indicate that when anxiety levels are very high, this could over-activate the orientating and alerting functions and to reduce the capacity of attentional control. These processes could have a negative impact on specific attentional processes and become a negative influence on performance in exams. © 2014 International Union of Psychological Science.

Immunochemical analytical methods for the determination of peanut proteins in foods.

PubMed

Whitaker, Thomas B; Williams, Kristina M; Trucksess, Mary W; Slate, Andrew B

2005-01-01

Peanut proteins can cause allergenic reactions that can result in respiratory and circulatory effects in the body sometimes leading to shock and death. The determination of peanut proteins in foods by analytical methods can reduce the risk of serious reactions in the highly sensitized individual by allowing for the detection of these proteins in a food at various stages of the manufacturing process. The method performance of 4 commercially available enzyme-linked immunosorbent assay (ELISA) kits was evaluated for the detection of peanut proteins in milk chocolate, ice cream, cookies, and breakfast cereals: ELISA-TEK Peanut Protein Assay, now known as "Bio-Kit" for peanut proteins, from ELISA Technologies Inc.; Veratox for Peanut Allergens from Neogen Corp.; RIDASCREEN Peanut Kit from R-Biopharm GmbH; and ProLisa from Canadian Food Technology Ltd. The 4 test kits were evaluated for accuracy (recovery) and precision using known concentrations of peanut or peanut proteins in the 4 food matrixes. Two different techniques, incurred and spiked, were used to prepare samples with 4 known concentrations of peanut protein. Defatted peanut flour was added in the incurred samples, and water-soluble peanut proteins were added in the spiked samples. The incurred levels were 0.0, 10, 20, and 100 microg whole peanut per g food; the spiked levels were 0.0, 5, 10, and 20 microg peanut protein per g food. Performance varied by test kit, protein concentration, and food matrix. The Veratox kit had the best accuracy or lowest percent difference between measured and incurred levels of 15.7% when averaged across all incurred levels and food matrixes. Recoveries associated with the Veratox kit varied from 93 to 115% for all food matrixes except cookies. Recoveries for all kits were about 50% for cookies. The analytical precision, as measured by the variance, increased with an increase in protein concentration. However, the coefficient of variation (CV) was stable across the 4 incurred protein levels and was 7.0% when averaged across the 4 food matrixes and analytical kits. The R-Biopharm test kit had the best precision or a CV of 4.2% when averaged across all incurred levels and food matrixes. Because measured protein values varied by test kit and food matrix, a method was developed to normalize or transform measured protein concentrations to an adjusted protein value that was equal to the known protein concentration. The normalization method adjusts measured protein values to equal the true protein value regardless of the type test kit or type food matrix.

Electrochemical probing of high-level radioactive waste tanks containing washed sludge and precipitates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bickford, D.F.; Congdon, J.W.; Oblath, S.B.

1986-12-01

At the US Department of Energy's Savannah River Plant, corrosion of carbon steel storage tanks containing alkaline, high-level radioactive waste is controlled by specification of limits on waste composition and temperature. Processes for the preparation of waste for final disposal will result in waste with low corrosion inhibitor concentrations and, in some cases, high aromatic organic concentrations, neither of which are characteristic of previous operations. Laboratory tests, conducted to determine minimum corrosion inhibitor levels indicated pitting of carbon steel near the waterline for proposed storage conditions. In situ electrochemical measurements of full-scale radioactive process demonstrations have been conducted to assessmore » the validity of laboratory tests. Probes included pH, Eh (potential relative to a standard hydrogen electrode), tank potential, and alloy coupons. In situ results are compared to those of the laboratory tests, with particular regard given to simulated solution composition. Transition metal hydroxide sludge contains strong passivating species for carbon steel. Washed precipitate contains organic species that lower solution pH and tend to reduce passivating films, requiring higher inhibitor concentrations than the 0.01 molar nitrite required for reactor fuel reprocessing wastes. Periodic agitation, to keep the organic phase suspended, or cathodic protection are possible alternatives to higher nitrite inhibitor concentrations.« less

Micro-abrasion-corrosion behaviour of a biomedical Ti-25Nb-3Mo-3Zr-2Sn alloy in simulated physiological fluid.

PubMed

Wang, Zhenguo; Li, Yan; Huang, Weijiu; Chen, Xiaoli; He, Haoran

2016-10-01

The micro-abrasion-corrosion behaviour of the biomedical Ti-25Nb-3Mo-3Zr-2Sn alloy in Hank׳s solution with protein has been investigated using electrochemical measurements, tribological tests and scanning electron microscope (SEM) observations. The potentiodynamic polarization tests showed that the corrosion potential (Ecorr) exhibits the maximum value at the abrasive concentration of 0.05gcm(-3) despite of the load level. The tribological results indicated that the total material loss of the Ti-25Nb-3Mo-3Zr-2Sn alloy during micro-abrasion increased with the increasing abrasive concentration at a certain applied load. When the abrasive concentration is no more than 0.15gcm(-3), the total material loss increases with increasing load, while the total material loss exhibits the maximum value at a moderate load in case of higher abrasive concentration levels. This was ascribed to the three-body or two-body micro-abrasion-corrosion at different abrasive concentration levels. The wastage map, abrasion mode map and synergy map associated with the applied load and the abrasive concentration were constructed to evaluate the micro-abrasion-corrosion behaviour of the Ti-25Nb-3Mo-3Zr-2Sn alloy in potential biomedical applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Blood alcohol concentration testing and reporting by the states : traffic tech.

DOT National Transportation Integrated Search

2012-08-01

Accurate and complete data on blood alcohol concentration : (BAC) levels for drivers in fatal crashes are critical in monitoring : alcohol-impaired-driving rates across the country, developing : alcohol-impaired-driving programs, and evaluating : the...

Toxic effects of isoproturon on periphyton communities a microcosm study

NASA Astrophysics Data System (ADS)

Schmitt-Jansen, Mechthild; Altenburger, Rolf

2005-02-01

Coastal and estuarine ecosystems are increasingly exposed to herbicide contamination. To study the potential risks of these pollutants, the establishment of periphyton communities under exposure of a concentration series of isoproturon in a range of 0.0024-0.312 mg L -1 was investigated in a microcosm study. After two weeks of growth, chronic effects on biomass development, measured as Chl a fluorescence, taxonomic composition and photosynthetic capacity of PS II of attached microalgae were analysed using a pulse-amplitude modulated (PAM) fluorescence-based method. Algal classes were differentiated according to their pigment systems using four excitation wavelengths. Biomass remained constant up to pre-exposure concentrations of 0.02 mg L -1 isoproturon but decreased within one order of magnitude at the highest test concentration. Algal classes shifted from diatoms to chlorophytes at pre-exposure concentrations of 0.02-0.39 mg L -1. Community structure of diatoms representing the dominant group of attached algae at lower test concentrations was studied by microscopic analysis revealing that species numbers were highest at lowest test concentrations as compared to controls. At higher test concentrations Navicula halophila dominated with 89% of the diatom biomass but was abnormally shaped. Pollution-induced community tolerance (PICT) of periphyton to isoproturon was determined by short-term inhibition tests of photosynthesis. Pre-exposed communities increased their effect concentrations (EC 50) up to threefold within the 0.039 mg L -1 pre-treatment. Our results suggest that attached microalgal communities have a high potential of tolerance development to isoproturon at lower levels of contamination due to the replacement of sensitive species by more tolerant algae, although these species seemed to be affected too. We conclude that herbicide concentrations in river basins, estuaries or coastal zones may change community structure and primary production of microphytobenthos even when the contamination does not exceed levels of acute toxicity.

Numerical Simulation of the Effect about Groundwater Level Fluctuation on the Concentration of BTEX Dissolved into Source Zone

NASA Astrophysics Data System (ADS)

Sun, Liqun; Chen, Yudao; Jiang, Lingzhi; Cheng, Yaping

2018-01-01

The water level fluctuation of groundwater will affect the BTEX dissolution in the fuel leakage source zone. In order to study the effect, a leakage test of gasoline was performed in the sand-tank model in the laboratory, and the concentrations of BTEX along with water level were monitored over a long period. Combined with VISUAL MODFLOW software, RT3D module was used to simulate the concentrations of BTEX, and mass flux method was used to evaluate the effects of water level fluctuation on the BTEX dissolution. The results indicate that water level fluctuation can significantly increase the concentration of BTEX dissolved in the leakage source zone. The dissolved amount of BTEX can reach up to 2.4 times under the water level fluctuation condition. The method of numerical simulation combined with mass flux calculation can be used to evaluate the effect of water level fluctuation on BTEX dissolution.

Rapid measurement of fibrinogen concentration in whole blood using a steel ball coagulometer

PubMed Central

Schlimp, Christoph J.; Khadem, Anna; Klotz, Anton; Solomon, Cristina; Hochleitner, Gerald; Ponschab, Martin; Redl, Heinz; Schöchl, Herbert

2015-01-01

BACKGROUND Fibrinogen plays a key role in hemostasis and is the first coagulation factor to reach critical levels in bleeding patients. Current European guidelines on the management of traumatic or perioperative bleeding recommend fibrinogen supplementation at specific threshold levels. Whole blood viscoelastic tests provide fast evaluation of fibrin deficits. Fast measurement of plasma fibrinogen concentration is not yet available. We investigated a method to rapidly determine whole blood fibrinogen concentration using standard Clauss assays and a steel ball coagulometer and provide an estimate of the “plasma-equivalent” fibrinogen concentration within minutes by adjustment of the measured whole blood fibrinogen concentration with a quickly measureable hemoglobin-derived hematocrit. METHODS The feasibility of this approach was tested with a Clauss assay using multiple porcine fresh blood samples obtained during in vivo bleeding, hemodilution, and after treatment with hemostatic therapy. Two different Clauss assays were then tested using multiple human volunteers’ blood samples diluted in vitro and supplemented with fibrinogen concentrate. Comparative measurements with fibrin-based thromboelastometry tests were performed. RESULTS Regression and Bland-Altman analyses of derived “plasma-equivalent” fibrinogen and measured plasma fibrinogen concentration was excellent in porcine and human blood samples, especially in the ranges relevant to traumatic or perioperative bleeding. CONCLUSION Fast whole blood fibrinogen measurements could be considered as an alternative to plasma fibrinogen measurement for acute bleeding management in trauma and perioperative care settings. Further studies are needed to prove this concept and determine the turnaround times for its clinical application in emergency departments and operating theaters. PMID:25742256

Trace elements and electrolytes in human resting mixed saliva after exercise

PubMed Central

Chicharro, J. L.; Serrano, V.; Urena, R.; Gutierrez, A. M.; Carvajal, A.; Fernandez-, H; Lucia, A.

1999-01-01

OBJECTIVES: Exercise is known to cause changes in the concentration of salivary components such as amylase, Na, and Cl. The aim of this investigation was to evaluate the effect of physical exercise on the levels of trace elements and electrolytes in whole (mixed) saliva. METHODS: Forty subjects performed a maximal exercise test on a cycle ergometer. Samples of saliva were obtained before and immediately after the exercise test. Sample concentrations of Fe, Mg, Sc, Cr, Mn, Co, Cu, Zn, Se, Sr, Ag, Sb, Cs, and Hg were determined by inductively coupled plasma mass spectrometry and concentrations of Ca and Na by atomic absorption spectrometry. RESULTS: After exercise, Mg and Na levels showed a significant increase (p < 0.05) while Mn levels fell (p < 0.05). Zn/Cu molar ratios were unaffected by exercise. CONCLUSIONS: Intense physical exercise induced changes in the concentrations of only three (Na, Mg, and Mn) of the 16 elements analysed in the saliva samples. Further research is needed to assess the clinical implications of these findings. 


 PMID:10378074

The influence of occupational heat exposure on cognitive performance and blood level of stress hormones: a field study report.

PubMed

Mazlomi, Adel; Golbabaei, Farideh; Farhang Dehghan, Somayeh; Abbasinia, Marzieh; Mahmoud Khani, Somayeh; Ansari, Mohammad; Hosseini, Mostafa

2017-09-01

This article aimed to investigate the effect of heat stress on cognitive performance and the blood concentration of stress hormones among workers of a foundry plant. Seventy workers within the exposed (35 people) and unexposed (35 people) groups were studied. The wet bulb globe temperature (WBGT) index was measured for heat stress assessment. The cognitive performance tests were conducted using the Stroop color word test (SCWT) before and during working hours. For the assessment of the serum level of cortisol and the plasma level of adrenaline and noradrenaline, blood samples were taken during working hours from both groups. Only for SCWT III was there a significant relationship between heat stress and test duration, error rate and reaction time. The laboratory test results revealed significantly higher concentrations of cortisol, adrenaline and noradrenaline in the exposed subjects than in the unexposed group. There existed a positive correlation between cortisol, adrenaline, noradrenaline and WBGT index and also test duration and reaction time of SCWT III, and number of errors of SCWT I, SCWT II and SCWT III during work. Heat stress can lead to an increase in the blood level of stress hormones, resulting in cognitive performance impairment.

Decreased expression of indolamine 2,3-dioxygenase in childhood allergic asthma and its inverse correlation with fractional concentration of exhaled nitric oxide.

PubMed

Hu, Ying; Chen, Zhiqiang; Jin, Ling; Wang, Mei; Liao, Wei

2017-11-01

The tryptophan metabolic pathway mediated by indolamine 2,3-dioxygenase (IDO), a tryptophan-degrading enzyme, plays an important role in controlling the development of allergic inflammation. The fractional concentration of exhaled nitric oxide (FeNO) is closely associated with the allergic state and is extensively used for the clinical evaluation of airway allergic inflammation. Clinical trials have rarely assessed the expression of IDO in childhood allergic asthma and its correlation with FeNO. To evaluate the IDO level in children with childhood allergic asthma and the relation between IDO levels and FeNO. Thirty children older than 5 years who were diagnosed the first time with allergic asthma were selected from the pediatric outpatient department. Another 30 healthy children were selected as controls. The subjects were evaluated by complete medical history, pulmonary function test results, skin prick test reaction, FeNO concentration test result, eosinophil count, and a disease severity score. Peripheral venous blood and induced sputum were obtained to measure the concentrations of IDO metabolites (ie, tryptophan and kynurenine). The IDO levels in the peripheral blood and induced sputum were significantly lower in patients with childhood allergic asthma than in children in the control group. The IDO level was negatively correlated with FeNO but was not significantly correlated with age, sex, blood eosinophil count, or disease severity scale. The expression of IDO was significantly lower in childhood allergic asthma, particularly in children with high FeNO levels. There was no significant relation between IDO levels and asthma severity. Chinese Clinical Trial Register (www.chictr.org.cn) Identifier: ChiCTR-COC-15006080. Copyright © 2017 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Analysis of the safety and pharmacodynamics of human fibrinogen concentrate in animals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beyerle, Andrea, E-mail: andrea.beyerle@cslbehring.com; Nolte, Marc W.; Solomon, Cristina

Fibrinogen, a soluble 340 kDa plasma glycoprotein, is critical in achieving and maintaining hemostasis. Reduced fibrinogen levels are associated with an increased risk of bleeding and recent research has investigated the efficacy of fibrinogen concentrate for controlling perioperative bleeding. European guidelines on the management of perioperative bleeding recommend the use of fibrinogen concentrate if significant bleeding is accompanied by plasma fibrinogen levels less than 1.5–2.0 g/l. Plasma-derived human fibrinogen concentrate has been available for therapeutic use since 1956. The overall aim of the comprehensive series of non-clinical investigations presented was to evaluate i) the pharmacodynamic and pharmacokinetic characteristics and ii)more » the safety and tolerability profile of human fibrinogen concentrate Haemocomplettan P® (RiaSTAP®). Pharmacodynamic characteristics were assessed in rabbits, pharmacokinetic parameters were determined in rabbits and rats and a safety pharmacology study was performed in beagle dogs. Additional toxicology tests included: single-dose toxicity tests in mice and rats; local tolerance tests in rabbits; and neoantigenicity tests in rabbits and guinea pigs following the introduction of pasteurization in the manufacturing process. Human fibrinogen concentrate was shown to be pharmacodynamically active in rabbits and dogs and well tolerated, with no adverse events and no influence on circulation, respiration or hematological parameters in rabbits, mice, rats and dogs. In these non-clinical investigations, human fibrinogen concentrate showed a good safety profile. This data adds to the safety information available to date, strengthening the current body of knowledge regarding this hemostatic agent. - Highlights: • A comprehensive series of pre-clinical investigations of human fibrinogen concentrate. • Human fibrinogen concentrate was shown to be pharmacodynamically active. • Human fibrinogen concentrate was well tolerated, with no adverse events. • Overall, human fibrinogen concentrate demonstrated a good safety profile. • This data adds to the safety information available to date on this hemostatic agent.« less

Are There Dangerous Levels of Lead in Local Soil?

NASA Astrophysics Data System (ADS)

Pita, I.

2017-12-01

The purpose of this experiment was to show that comparing random soil samples from areas in New Orleans; the Garden District will have the highest levels of lead in soil. My Independent variable was the soil samples collected from locations in the Garden District area of New Orleans, and other locations throughout New Orleans. The control was the soil samples collected from the local playground in the New Orleans area. My dependent variable was the lead soil test kit, using ppm (parts per million) of lead to show concentration. 400 ppm + in bare soil where children play is considered dangerous hazard levels. 1,000 + ppm in all other areas is considered dangerous hazard levels. The first step to my experiment, I collected soil samples from different locations throughout the Garden District area of New Orleans. The second step to my experiment, I conducted the lead soil testing in a controlled area at home in a well ventilated room, using all the necessary safety equipment needed, I began testing a 24 hour test period and a 48 hour test period. I then collected the data from both test. The results showed that soil samples from the Garden District area compared to the other sample locations had higher lead concentrations in the soil. This backed my hypothesis when comparing soil samples from areas in New Orleans, the Garden District will have the highest lead levels. In conclusion these experiments showed that with the soil samples collected, there were higher concentrations of lead in the soil from the Garden District area compared to the other areas where soil was collected. Reconstruction and renovations, from the devastation that Hurricane Katrina created, are evident of the lead in paint of older homes which now show the lead concentration in the soil. Lead is a lethal element if consumed or inhaled in high doses, which can damage key organs in our body, which can be deadly. Better awareness through social media, television, radio, doctors, studies, pamphlets, environmental agencies, and other forms to address the steps in protecting your family and home for a lead free environment.

Interaction of DRD4 Methylation and Phthalate Metabolites Affects Continuous Performance Test Performance in ADHD.

PubMed

Kim, Johanna Inhyang; Kim, Jae-Won; Shin, Inkyung; Kim, Bung-Nyun

2018-05-01

We investigated the interaction effect between the methylation of dopamine receptor D4 (DRD4) and phthalate exposure in ADHD on continuous performance test (CPT) variables. Urine concentrations of mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), and mono-n-butyl phthalate (MBP) were tested. The methylation status was analyzed for CpG sites of DRD4. Multivariable linear regression models were applied to investigate the interaction effects of methylation and phthalate levels. There was a significant interaction effect of the methylation of CpG26 and CpG28 with the MEHHP level on omission errors in ADHD patients, but not in controls. The post hoc analysis revealed a significant correlation between the MEHHP concentration and omission errors in the methylated group, but not in the unmethylated group. The interaction between the methylation status of CpG sites of DRD4, particularly CpG26 and CpG28, and phthalate metabolite levels affects the attention level in ADHD patients.

Expression of the androgen receptor in the testes and the concentrations of gonadotropins and sex steroid hormones in male turkeys (Meleagris gallopavo) during growth and development.

PubMed

Kiezun, J; Leska, A; Kaminska, B; Jankowski, J; Dusza, L

2015-04-01

Androgens, including testosterone (T) and androstenedione (A4), are essential for puberty, fertility and sexual functions. The biological activity of those hormones is mediated via the androgen receptor (AR). The regulation of androgen action in birds is poorly understood. Therefore, the present study analysed mRNA and protein expression of AR in the testes, plasma concentrations of the luteinizing hormone (LH), follicle-stimulating hormone (FSH), T, A4 and oestradiol (E2), as well as the levels of T, A4 and E2 in testicular homogenates of male turkeys (Meleagris gallopavo) at the age of 4, 8, 12, 16, 20, 24 and 28weeks. Plasma concentrations of LH and FSH, as well as plasma and testicular levels of T and A4 began to increase at 20weeks of age. The lowest plasma levels of E2 were noted at 20weeks relative to other growth stages. The 20th week of life seems to be the key phase in the development of the reproductive system of turkeys. The AR protein was found in the nuclei of testicular cells in all examined growth stages. Higher expression of AR protein in the testes beginning at 20weeks of age was accompanied by high plasma concentrations of LH and high plasma and testicular levels of androgens. This relationship seems to be necessary to regulate male sexual function. Copyright © 2014 Elsevier Inc. All rights reserved.

Electrochemical probing of high-level radioactive waste tanks containing washed sludge and precipitates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bickford, D.F.; Congdon, J.W.; Oblath, S.B.

1987-01-01

At the U.S. Department of Energy's Savannah River Plant, corrosion of carbon steel storage tanks containing alkaline, high-level radioactive waste is controlled by specification of limits on waste composition and temperature. Processes for the preparation of waste for final disposal will result in waste with low corrosion inhibitor concentrations and, in some cases, high aromatic organic concentrations, neither of which are characteristic of previous operations. Laboratory tests, conducted to determine minimum corrosion inhibitor levels indicated pitting of carbon steel near the waterline for proposed storage conditions. In situ electrochemical measurements of full-scale radioactive process demonstrations have been conducted to assessmore » the validity of laboratory tests. Probes included pH, Eh (potential relative to a standard hydrogen electrode), tank potential, and alloy coupons. In situ results are compared to those of the laboratory tests, with particular regard given to simulated solution composition.« less

Simultaneously reducing CO2 and particulate exposures via fractional recirculation of vehicle cabin air.

PubMed

Jung, Heejung S; Grady, Michael L; Victoroff, Tristan; Miller, Arthur L

2017-07-01

Prior studies demonstrate that air recirculation can reduce exposure to nanoparticles in vehicle cabins. However when people occupy confined spaces, air recirculation can lead to carbon dioxide (CO 2 ) accumulation which can potentially lead to deleterious effects on cognitive function. This study proposes a fractional air recirculation system for reducing nanoparticle concentration while simultaneously suppressing CO 2 levels in the cabin. Several recirculation scenarios were tested using a custom-programmed HVAC (heat, ventilation, air conditioning) unit that varied the recirculation door angle in the test vehicle. Operating the recirculation system with a standard cabin filter reduced particle concentrations to 1000 particles/cm 3 , although CO 2 levels rose to 3000 ppm. When as little as 25% fresh air was introduced (75% recirculation), CO 2 levels dropped to 1000 ppm, while particle concentrations remained below 5000 particles/cm 3 . We found that nanoparticles were removed selectively during recirculation and demonstrated the trade-off between cabin CO 2 concentration and cabin particle concentration using fractional air recirculation. Data showed significant increases in CO 2 levels during 100% recirculation. For various fan speeds, recirculation fractions of 50-75% maintained lower CO 2 levels in the cabin, while still reducing particulate levels. We recommend fractional recirculation as a simple method to reduce occupants' exposures to particulate matter and CO 2 in vehicles. A design with several fractional recirculation settings could allow air exchange adequate for reducing both particulate and CO 2 exposures. Developing this technology could lead to reductions in airborne nanoparticle exposure, while also mitigating safety risks from CO 2 accumulation.

Simultaneously reducing CO2 and particulate exposures via fractional recirculation of vehicle cabin air

PubMed Central

Jung, Heejung S.; Grady, Michael L.; Victoroff, Tristan; Miller, Arthur L.

2017-01-01

Prior studies demonstrate that air recirculation can reduce exposure to nanoparticles in vehicle cabins. However when people occupy confined spaces, air recirculation can lead to carbon dioxide (CO2) accumulation which can potentially lead to deleterious effects on cognitive function. This study proposes a fractional air recirculation system for reducing nanoparticle concentration while simultaneously suppressing CO2 levels in the cabin. Several recirculation scenarios were tested using a custom-programmed HVAC (heat, ventilation, air conditioning) unit that varied the recirculation door angle in the test vehicle. Operating the recirculation system with a standard cabin filter reduced particle concentrations to 1000 particles/cm3, although CO2 levels rose to 3000 ppm. When as little as 25% fresh air was introduced (75% recirculation), CO2 levels dropped to 1000 ppm, while particle concentrations remained below 5000 particles/cm3. We found that nanoparticles were removed selectively during recirculation and demonstrated the trade-off between cabin CO2 concentration and cabin particle concentration using fractional air recirculation. Data showed significant increases in CO2 levels during 100% recirculation. For various fan speeds, recirculation fractions of 50–75% maintained lower CO2 levels in the cabin, while still reducing particulate levels. We recommend fractional recirculation as a simple method to reduce occupants’ exposures to particulate matter and CO2 in vehicles. A design with several fractional recirculation settings could allow air exchange adequate for reducing both particulate and CO2 exposures. Developing this technology could lead to reductions in airborne nanoparticle exposure, while also mitigating safety risks from CO2 accumulation. PMID:28781568

Simultaneously reducing CO2 and particulate exposures via fractional recirculation of vehicle cabin air

NASA Astrophysics Data System (ADS)

Jung, Heejung S.; Grady, Michael L.; Victoroff, Tristan; Miller, Arthur L.

2017-07-01

Prior studies demonstrate that air recirculation can reduce exposure to nanoparticles in vehicle cabins. However when people occupy confined spaces, air recirculation can lead to carbon dioxide (CO2) accumulation which can potentially lead to deleterious effects on cognitive function. This study proposes a fractional air recirculation system for reducing nanoparticle concentration while simultaneously suppressing CO2 levels in the cabin. Several recirculation scenarios were tested using a custom-programmed HVAC (heat, ventilation, air conditioning) unit that varied the recirculation door angle in the test vehicle. Operating the recirculation system with a standard cabin filter reduced particle concentrations to 1000 particles/cm3, although CO2 levels rose to 3000 ppm. When as little as 25% fresh air was introduced (75% recirculation), CO2 levels dropped to 1000 ppm, while particle concentrations remained below 5000 particles/cm3. We found that nanoparticles were removed selectively during recirculation and demonstrated the trade-off between cabin CO2 concentration and cabin particle concentration using fractional air recirculation. Data showed significant increases in CO2 levels during 100% recirculation. For various fan speeds, recirculation fractions of 50-75% maintained lower CO2 levels in the cabin, while still reducing particulate levels. We recommend fractional recirculation as a simple method to reduce occupants' exposures to particulate matter and CO2 in vehicles. A design with several fractional recirculation settings could allow air exchange adequate for reducing both particulate and CO2 exposures. Developing this technology could lead to reductions in airborne nanoparticle exposure, while also mitigating safety risks from CO2 accumulation.

Stratifying low level Isoniazid resistance using additional intermediate drug concentration.

PubMed

Lakshmi, Rajagopalan; Ramachandran, Ranjani; Sundar, A Syam; Rahman, Fathima; Kumar, Vanaja

2014-06-01

Isoniazid (INH) susceptibility testing for 100 Mycobacterium tuberculosis performed by conventional minimum inhibitory concentration (MIC) method was stratified using additional drug concentrations. Introduction of additional drug concentrations did not greatly improve the discriminatory capacity, but can be used in specialized studies pertaining to cross resistance between structural analogues of INH. Copyright © 2014 Asian-African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.

Plutonium in the atmosphere: A global perspective.

PubMed

Thakur, P; Khaing, H; Salminen-Paatero, S

2017-09-01

A number of potential source terms have contributed plutonium isotopes to the atmosphere. The atmospheric nuclear weapon tests conducted between 1945 and 1980 and the re-entry of the burned SNAP-9A satellite in 1964, respectively. It is generally believed that current levels of plutonium in the stratosphere are negligible and compared with the levels generally found at surface-level air. In this study, the time trend analysis and long-term behavior of plutonium isotopes ( 239+240 Pu and 238 Pu) in the atmosphere were assessed using historical data collected by various national and international monitoring networks since 1960s. An analysis of historical data indicates that 239+240 Pu concentration post-1984 is still frequently detectable, whereas 238 Pu is detected infrequently. Furthermore, the seasonal and time-trend variation of plutonium concentration in surface air followed the stratospheric trends until the early 1980s. After the last Chinese test of 1980, the plutonium concentrations in surface air dropped to the current levels, suggesting that the observed concentrations post-1984 have not been under stratospheric control, but rather reflect the environmental processes such as resuspension. Recent plutonium atmospheric air concentrations data show that besides resuspension, other environmental processes such as global dust storms and biomass burning/wildfire also play an important role in redistributing plutonium in the atmosphere. Copyright © 2017 Elsevier Ltd. All rights reserved.

Analysis of the origin and importance of acetone and isopropanol levels in the blood of the deceased for medico-legal testimony.

PubMed

Borowska-Solonynko, A; Siwińska-Ziółkowska, A; Piotrkowicz, M; Wysmołek, M; Demkow, M

2014-01-01

The aim of the study was to analyze the incidence of acetone and isopropanol in the blood of the deceased, and to assess cases in which the compounds have been detected with a focus on their origin and usefulness for medico-legal testimony. The study material consisted of results of tests detecting ethyl alcohol and reports of autopsies performed at the Department of Forensic Medicine, Medical University of Warsaw, from January 2008 to April 2009 - a total of 2,475 cases. The test group proper (group B) comprised only those cases in which acetone was detected in blood, either with or without isopropanol [n = 202 (8.2%)]. The blood levels of isopropanol varied depending on the cause of death. The need for differentiating the origin of isopropanol in the case of its presence in the blood of the deceased was pointed out. The results of the present study show that the differentiation should be based on the isopropanol and acetone concentration ratio, as isopropanol concentration alone is not sufficient for preparing expert opinions. Even high concentrations of isopropanol, when accompanied by even higher concentrations of acetone, imply that isopropanol could have been formed as a result of acetone transformations. Isopropanol concentrations exceeding acetone levels strongly point to the exogenous origin of isopropanol, particularly when high levels of ethanol are concurrently detected.

Higher direct bilirubin levels during mid-pregnancy are associated with lower risk of gestational diabetes mellitus.

PubMed

Liu, Chaoqun; Zhong, Chunrong; Zhou, Xuezhen; Chen, Renjuan; Wu, Jiangyue; Wang, Weiye; Li, Xiating; Ding, Huisi; Guo, Yanfang; Gao, Qin; Hu, Xingwen; Xiong, Guoping; Yang, Xuefeng; Hao, Liping; Xiao, Mei; Yang, Nianhong

2017-01-01

Bilirubin concentrations have been recently reported to be negatively associated with type 2 diabetes mellitus. We examined the association between bilirubin concentrations and gestational diabetes mellitus. In a prospective cohort study, 2969 pregnant women were recruited prior to 16 weeks of gestation and were followed up until delivery. The value of bilirubin was tested and oral glucose tolerance test was conducted to screen gestational diabetes mellitus. The relationship between serum bilirubin concentration and gestational weeks was studied by two-piecewise linear regression. A subsample of 1135 participants with serum bilirubin test during 16-18 weeks gestation was conducted to research the association between serum bilirubin levels and risk of gestational diabetes mellitus by logistic regression. Gestational diabetes mellitus developed in 8.5 % of the participants (223 of 2969). Two-piecewise linear regression analyses demonstrated that the levels of bilirubin decreased with gestational week up to the turning point 23 and after that point, levels of bilirubin were increased slightly. In multiple logistic regression analysis, the relative risk of developing gestational diabetes mellitus was lower in the highest tertile of direct bilirubin than that in the lowest tertile (RR 0.60; 95 % CI, 0.35-0.89). The results suggested that women with higher serum direct bilirubin levels during the second trimester of pregnancy have lower risk for development of gestational diabetes mellitus.

The Effects of Oxygen Concentration on Benthic Foraminiferal Growth and Size

NASA Astrophysics Data System (ADS)

Ng, B.; Keating-Bitonti, C.; Payne, J.

2015-12-01

Many organisms use oxygen through cellular respiration in order to gain energy. For this reason, oxygen has a significant influence on organism size and growth. The amount of oxygen an organism needs depends on its metabolic demand, which is partially a function organism size (i.e., mass). The Santa Monica Basin (SMB) is an oxygen minimum zone located off the southern coast of California that maintains a steep oxygen gradient and is thus an ideal location for conducting research on how oxygen influences organism size. Here we use benthic foraminifera, widespread single-celled protists that produce shells (tests), to study the controls of oxygen on organism size. Because cell mass and cell volume are correlated, we study trends in the log test volume of four abundant species from SMB: Uvigerina peregrina, Bolivina spissa, B. argentea, Loxostomum pseudobeyrichi. These foraminifera make multi-chambered tests, thus we also count the number of chambers per specimen in order to further assess their growth under varying oxygen concentrations. We analyzed the data using quantile regressions to determine trends in not only median values of the log test volume and number of chambers as a function of oxygen concentrations, but also in the 10th, 25th, 75th, and 90th percentiles because oxygen availability often constrains the maximum and minimum size of organisms. Our results show a positive correlation between oxygen concentration and the maximum log test volumes of L. pseudobeyrichi and B. argentea, supporting our hypothesis. However, we observed a negative correlation between oxygen concentration and the maximum percentiles of log test volume in U. peregrina. Nevertheless, U. peregrina still displays a positive correlation between chamber number and oxygen concentrations in line with our hypothesis. The preponderance of trends supporting a direct correlation between log test volume or chamber number and oxygen concentration suggest that oxygen limits the maximum obtainable size of benthic foraminifera through its effects on test volume or chamber growth. This study is important because it holds a glimpse into how changes in oxygen levels can affect organisms given current fluctuations in oxygen level around the world due to man-made climate change.

Some effects of Heptachlor on bluegills (Lepomis macrochirus)

USGS Publications Warehouse

Andrews, Austin K.; Stebbings, Bruce E.; Van Valin, Charles C.

1966-01-01

In complementary studies of the chronic effects of heptachlor on bluegills, four similar earthen ponds were treated once with different concentrations of heptachlor, and the fish in six plastic pools were routinely fed different levels of heptachlor. A fifth pond and two plastic pools were used as controls. Higher dosages resulted in higher concentrations of heptachlor residues, more pronounced tissue pathology, and higher mortality in the test fish. Heptachlor reached a maximum in the pond fish about 3 days after treatment, and could no longer be found in the fish or mud after 56 days. The fish fed continuous levels of heptachlor developed their highest residues at 56 days. Invertebrate populations in the two higher treatment level ponds were eliminated. Lesser effects appeared in the two lower concentrations. At the termination of the experiment, invertebrate populations in the treated ponds and the control were not significantly different, and had achieved or surpassed pretreatment levels. Degenerative liver lesions became pronounced in fish from the two higher exposure ponds, but a heavy infestation of trematode metacercariae in the fish of all the test ponds, except the control, clouded further interpretation of histopathological examinations. Pathology results from the fish in the feeding test, although inconclusive, tended to support the trends which were developing in the contact test. There was an inverse proportional relationship between growth of fish in the feeding test and the amount of heptachlor introduced. The control group showed the highest growth rate, and the groups with progressively higher intake of heptachlor had progressively lower growth rates.

A CO2 concentration gradient facility for testing CO2 enrichment and soil effects on grassland ecosystem function

USDA-ARS?s Scientific Manuscript database

Continuing increases in atmospheric CO2 concentrations mandate techniques for examining impacts on terrestrial ecosystems. Most experiments examine only two or a few levels of CO2 concentration and a single soil type, but if CO2 can be varied as a gradient from subambient to superambient concentra...

Fourier Transform Infrared Absorption Spectroscopy for Quantitative Analysis of Gas Mixtures at Low Temperatures for Homeland Security Applications.

PubMed

Meier, D C; Benkstein, K D; Hurst, W S; Chu, P M

2017-05-01

Performance standard specifications for point chemical vapor detectors are established in ASTM E 2885-13 and ASTM E 2933-13. The performance evaluation of the detectors requires the accurate delivery of known concentrations of the chemical target to the system under test. Referee methods enable the analyte test concentration and associated uncertainties in the analyte test concentration to be validated by independent analysis, which is especially important for reactive analytes. This work extends the capability of a previously demonstrated method for using Fourier transform infrared (FT-IR) absorption spectroscopy for quantitatively evaluating the composition of vapor streams containing hazardous materials at Acute Exposure Guideline Levels (AEGL) to include test conditions colder than laboratory ambient temperatures. The described method covers the use of primary reference spectra to establish analyte concentrations, the generation of secondary reference spectra suitable for measuring analyte concentrations under specified testing environments, and the use of additional reference spectra and spectral profile strategies to mitigate the uncertainties due to impurities and water condensation within the low-temperature (7 °C, -5 °C) test cell. Important benefits of this approach include verification of the test analyte concentration with characterized uncertainties by in situ measurements co-located with the detector under test, near-real-time feedback, and broad applicability to toxic industrial chemicals.

Fourier Transform Infrared Absorption Spectroscopy for Quantitative Analysis of Gas Mixtures at Low Temperatures for Homeland Security Applications

PubMed Central

Meier, D.C.; Benkstein, K.D.; Hurst, W.S.; Chu, P.M.

2016-01-01

Performance standard specifications for point chemical vapor detectors are established in ASTM E 2885-13 and ASTM E 2933-13. The performance evaluation of the detectors requires the accurate delivery of known concentrations of the chemical target to the system under test. Referee methods enable the analyte test concentration and associated uncertainties in the analyte test concentration to be validated by independent analysis, which is especially important for reactive analytes. This work extends the capability of a previously demonstrated method for using Fourier transform infrared (FT-IR) absorption spectroscopy for quantitatively evaluating the composition of vapor streams containing hazardous materials at Acute Exposure Guideline Levels (AEGL) to include test conditions colder than laboratory ambient temperatures. The described method covers the use of primary reference spectra to establish analyte concentrations, the generation of secondary reference spectra suitable for measuring analyte concentrations under specified testing environments, and the use of additional reference spectra and spectral profile strategies to mitigate the uncertainties due to impurities and water condensation within the low-temperature (7 °C, −5 °C) test cell. Important benefits of this approach include verification of the test analyte concentration with characterized uncertainties by in situ measurements co-located with the detector under test, near-real-time feedback, and broad applicability to toxic industrial chemicals. PMID:28090126

Effect of various kinds of beverages on stress oxidative, F2 isoprostane, serum lipid and blood glucose of elite taekwondo players.

PubMed

Maghsoudi, Zahra; Shiranian, Ashfin; Askai, Gholamreza; Ghaisvand, Reza

2016-01-01

Athletes' recovery is important in improving their performance. Nutritional strategies can be effective in enhancing recovery rate. Choosing the best food items in appropriate intervals can play effective roles in resynthesis of fuels and recovery of muscle injury. Beverage micro and macronutrient content are helpful in fuel restoration. In this study, we assess the effects of various kinds of beverages on oxidative stress, muscle injury, and metabolic risk factors in taekwondo players. This quasi-experimental study was performed on 21 taekwondo players of Isfahan. After collecting fasting blood, they performed runningbased anaerobic sprint test (RAST). Blood lactate was tested again and participants were divided into 3 intervention groups, that is, receiving 500 cc dough, non-alcoholic beer, and chocolate milk at 4 day intervals. After a 2-h recovery period, blood sampling was repeated. Elites consumed other beverages in later phases. Dietary intake and fasting triglyceride, cholesterol, blood sugar, lactate dehydrogenase, and F 2 -isoprostane concentrations were determined. Data were analyzed with a simple repeated-measures test and post-hoc tests using the Statistical Package for the Social Sciences software. Data showed that cholesterol levels non-significantly decreased after intervention. Triglyceride level was lower after taking dough and carbohydrate replacement drink. Blood glucose concentration increased after intervention periods, however, this increase was significant only after non-alcoholic beverage consumption. Lactate dehydrogenase levels reduced after all cycles, however, F 2 -isoprostane level showed no significant change. There was not significant change in lactate dehydrogenase and F 2 -isoprostane levels. Non-alcoholic beer consumption can reduce lactate dehydrogenase concentration; however, it leads to blood sugar increase. Moreover, dough consumption significantly reduced triglyceride level in taekwondo players.

Utilizing the ultrasensitive Schistosoma up-converting phosphor lateral flow circulating anodic antigen (UCP-LF CAA) assay for sample pooling-strategies.

PubMed

Corstjens, Paul L A M; Hoekstra, Pytsje T; de Dood, Claudia J; van Dam, Govert J

2017-11-01

Methodological applications of the high sensitivity genus-specific Schistosoma CAA strip test, allowing detection of single worm active infections (ultimate sensitivity), are discussed for efficient utilization in sample pooling strategies. Besides relevant cost reduction, pooling of samples rather than individual testing can provide valuable data for large scale mapping, surveillance, and monitoring. The laboratory-based CAA strip test utilizes luminescent quantitative up-converting phosphor (UCP) reporter particles and a rapid user-friendly lateral flow (LF) assay format. The test includes a sample preparation step that permits virtually unlimited sample concentration with urine, reaching ultimate sensitivity (single worm detection) at 100% specificity. This facilitates testing large urine pools from many individuals with minimal loss of sensitivity and specificity. The test determines the average CAA level of the individuals in the pool thus indicating overall worm burden and prevalence. When requiring test results at the individual level, smaller pools need to be analysed with the pool-size based on expected prevalence or when unknown, on the average CAA level of a larger group; CAA negative pools do not require individual test results and thus reduce the number of tests. Straightforward pooling strategies indicate that at sub-population level the CAA strip test is an efficient assay for general mapping, identification of hotspots, determination of stratified infection levels, and accurate monitoring of mass drug administrations (MDA). At the individual level, the number of tests can be reduced i.e. in low endemic settings as the pool size can be increased as opposed to prevalence decrease. At the sub-population level, average CAA concentrations determined in urine pools can be an appropriate measure indicating worm burden. Pooling strategies allowing this type of large scale testing are feasible with the various CAA strip test formats and do not affect sensitivity and specificity. It allows cost efficient stratified testing and monitoring of worm burden at the sub-population level, ideally for large-scale surveillance generating hard data for performance of MDA programs and strategic planning when moving towards transmission-stop and elimination.

Comparison of heavy metal toxicity in continuous flow and batch reactors

NASA Astrophysics Data System (ADS)

Sengor, S. S.; Gikas, P.; Moberly, J. G.; Peyton, B. M.; Ginn, T. R.

2009-12-01

The presence of heavy metals may significantly affect microbial growth. In many cases, small amounts of particular heavy metals may stimulate microbial growth; however, larger quantities may result in microbial growth reduction. Environmental parameters, such as growth pattern may alter the critical heavy metal concentration, above which microbial growth stimulation turns to growth inhibition. Thus, it is important to quantify the effects of heavy metals on microbial activity for understanding natural or manmade biological reactors, either in situ or ex situ. Here we compare the toxicity of Zn and Cu on Arthrobacter sp., a heavy metal tolerant microorganism, under continuous flow versus batch reactor operations. Batch and continuous growth tests of Arthrobacter sp. were carried out at various individual and combined concentrations of Zn and Cu. Biomass concentration (OD) was measured for both the batch and continuous reactors, whereas ATP, oxygen uptake rates and substrate concentrations were additionally measured for the continuous system. Results indicated that Cu was more toxic than Zn under all conditions for both systems. In batch reactors, all tested Zn concentrations up to 150 uM showed a stimulatory effect on microbial growth. However, in the case of mixed Zn and Cu exposures, the presence of Zn either eliminated (at the 50 uM level both Zn and Cu) or reduced by ~25% (at the 100 and 150 uM levels both Zn and Cu) the Cu-induced inhibition. In the continuous system, only one test involved combined Cu (40uM) and Zn (125uM) and this test showed similar results to the 40uM Cu continuous test, i.e., no reduction in inhibition. The specific ATP concentration, i.e., ATP/OD, results for the continuous reactor showed an apparent recovery for both Cu-treated populations, although neither the OD nor glucose data showed any recovery. This may reflect that the individual microorganisms that survived after the addition of heavy metals, kept maintaining the usual ATP levels, as before metal addition. The last may imply a short of adaptation by some microorganisms to the presence of heavy metals. Overall, the batch reactor tests underestimated significantly the heavy metal inhibition, as compared to the continuous flow reactors. Therefore, the results of batch reactor tests should be used with some caution when heavy metal inhibition is to be interpreted for continuous flow natural environmental systems, such as rivers or wetlands.

Effects of ration level on immune functions in chinook salmon (Oncorhynchus tshawytscha)

USGS Publications Warehouse

Alcorn, S.W.; Pascho, R.J.; Murray, A.L.; Shearer, K.D.

2003-01-01

The relationship between nutritional status and disease resistance in cultured salmonids can be affected by dietary manipulations. Careful attention to feeding levels may be important to avoid imbalances in nutrient levels that could ultimately impair a fish's ability to resist infectious microorganisms. In the current study, fish in three feed-level groups were fed an experimental diet either to satiation, 64% of satiation or 40% of satiation. A fourth group of fish were fed a commercial diet at the 64% of satiation level and served as controls. To evaluate certain indices of disease resistance in the test and control fish, a panel of assays was employed to measure humoral and cellular immune functions 30, 39 and 54 weeks after starting the dietary treatments. The panel included measures of blood hematocrit and leucocrit levels, plasma protein concentration and serum lysozyme and complement activity. Cellular analyses included differential blood leucocyte counts, NBT reduction and phagocytosis by pronephros macrophages and myeloperoxidase activity of pronephros neutrophils. No differences were observed in those indices between fish tested from the control-diet group (commercial diet fed at the 64% rate) and fish tested from the 64% feed-level group, except that fish fed the commercial diet had a greater concentration of plasma protein. Leucocrit values and plasma protein concentrations tended to increase among the experimental feed groups as the ration increased from 40% to satiation. More importantly, phagocytic activity by anterior kidney leucocytes was found to be inversely proportional to the feed level. Whereas the results of this study provide evidence that the salmonid immune system may be fairly robust with regard to available metabolic energy, the significant changes observed in phagocytic cell activity suggest that some cellular immune functions may be affected by the feed level.

Elevated serum MDA and depleted non-enzymatic antioxidants, macro-minerals and trace elements are associated with bipolar disorder.

PubMed

Chowdhury, Manjurul Islam; Hasan, Maimuna; Islam, Mohammad Safiqul; Sarwar, Md Shahid; Amin, Mohammad Nurul; Uddin, S M Naim; Rahaman, Md Zahedur; Banik, Sujan; Hussain, Md Saddam; Yokota, Kazushige; Hasnat, Abul

2017-01-01

Genetic and neurobiological factors are considered to be the major causes of mood and mental disorders. However, over the past few years, increased levels of serum malondialdehyde and altered levels of various non-enzymatic antioxidants and essential minerals involved in abnormal functional activity have been identified as major contributing factors to the pathogenesis of several neurological disorders. The aim of this study was to determine the levels of the serum lipid peroxidation product malondialdehyde (MDA), antioxidants (vitamin A, E and C), macro-minerals (calcium, potassium and sodium) and trace elements (zinc, iron and selenium) in patients with bipolar disorder and to explore their role in disease progression. This is a prospective case-control study that evaluated 55 patients with bipolar disorder and 55 healthy volunteers matched by age and sex. Serum MDA levels were determined by UV spectrophotometry as a marker of lipid peroxidation. RP-HPLC was employed to investigate the serum vitamin A and E concentrations, whereas UV spectrophotometry was used to quantify levels of vitamin C. Serum macro-minerals and trace elements were analyzed by atomic absorption spectroscopy (AAS). Statistical analysis was performed with independent sample t-tests and Pearson's correlation test. We found significantly higher concentrations of MDA (p<0.05) and significantly lower concentrations of antioxidants (vitamin A, E and C) (p<0.05) in the patient group compared with control group. Regarding trace elements and macro-minerals, lower concentrations of zinc, calcium, iron, selenium, sodium and potassium were found in the patient group compared with control subjects (p<0.05). Our study suggests that high serum MDA concentrations and low serum concentrations of antioxidants, macro-minerals and trace elements are strongly associated with bipolar disorder. Copyright © 2016 Elsevier GmbH. All rights reserved.

Beta lactam antibiotics residues in cow's milk: comparison of efficacy of three screening tests used in Bosnia and Herzegovina.

PubMed

Fejzic, Nihad; Begagic, Muris; Šerić-Haračić, Sabina; Smajlovic, Muhamed

2014-08-27

Beta lactam antibiotics are widely used in therapy of cattle, particularly for the treatment of mastitis.  Over 95% of residue testing in dairies in Bosnia and Herzegovina is for Beta lactams. The aim of this paper is to compare the efficacy of three most common screening tests for Beta lactam residues in cow's milk in our country. The tests used in the study are SNAP β Lactam test (Idexx), Rosa Charm β Lactam test and Inhibition MRL test. Study samples included: standardized concentrations of penicillin solution (0, 2, 3, 4, 5 and 6 ppb). In addition we tested milk samples from three equal size study groups (not receiving any antibiotic therapy, treated with Beta lactams for mastitis and treated with Beta lactams for diseases other than mastitis). Sensitivity and specificity were determined for each test, using standard penicillin concentrations with threshold value set at concentration of 4 ppb (Maximum residue level - MLR). Additionally we determined proportions of presumably false negative and false positive results for each test using results of filed samples testing. Agreement of test results for each test pair was assessed through Kappa coefficients interpreted by Landis-Koch scale. Detection level of all tests was shown to be well below MRL. This alongside with effects of natural inhibitors in milk contributed to finding of positive results in untreated and treated animals after the withholding period. Screening tests for beta lactam residues are important tools for ensuring that milk for human consumption is free from antibiotics residues.

Beta lactam antibiotics residues in cow’s milk: comparison of efficacy of three screening tests used in Bosnia and Herzegovina

PubMed Central

Fejzić, Nihad; Begagić, Muris; Šerić-Haračić, Sabina; Smajlović, Muhamed

2014-01-01

Beta lactam antibiotics are widely used in therapy of cattle, particularly for the treatment of mastitis. Over 95% of residue testing in dairies in Bosnia and Herzegovina is for Beta lactams. The aim of this paper is to compare the efficacy of three most common screening tests for Beta lactam residues in cow’s milk in our country. The tests used in the study are SNAP β Lactam test (Idexx), Rosa Charm β Lactam test (Charm Sciences) and Inhibition MRL test (A&M). Study samples included: standardized concentrations of penicillin solution (0, 2, 3, 4, 5 and 6 ppb). In addition we tested milk samples from three equal size study groups (not receiving any antibiotic therapy, treated with Beta lactams for mastitis and treated with Beta lactams for diseases other than mastitis). Sensitivity and specificity were determined for each test, using standard penicillin concentrations with threshold value set at concentration of 4 ppb (Maximum residue level – MLR). Additionally we determined proportions of presumably false negative and false positive results for each test using results of filed samples testing. Agreement of test results for each test pair was assessed through Kappa coefficients interpreted by Landis-Koch scale. Detection level of all tests was shown to be well below MRL. This alongside with effects of natural inhibitors in milk contributed to finding of positive results in untreated and treated animals after the withholding period. Screening tests for beta lactam residues are important tools for ensuring that milk for human consumption is free from antibiotics residues. PMID:25172975

Antibiotic Concentrations Decrease during Wastewater Treatment but Persist at Low Levels in Reclaimed Water

PubMed Central

Kulkarni, Prachi; Olson, Nathan D.; Raspanti, Greg A.; Rosenberg Goldstein, Rachel E.; Gibbs, Shawn G.; Sapkota, Amir; Sapkota, Amy R.

2017-01-01

Reclaimed water has emerged as a potential irrigation solution to freshwater shortages. However, limited data exist on the persistence of antibiotics in reclaimed water used for irrigation. Therefore, we examined the fate of nine commonly-used antibiotics (ampicillin, azithromycin, ciprofloxacin, linezolid, oxacillin, oxolinic acid, penicillin G, pipemidic acid, and tetracycline) in differentially treated wastewater and reclaimed water from two U.S. regions. We collected 72 samples from two Mid-Atlantic and two Midwest treatment plants, as well as one Mid-Atlantic spray irrigation site. Antibiotic concentrations were measured using liquid-chromatography- tandem mass spectrometry. Data were analyzed using Mann-Whitney-Wilcoxon tests and Kruskal Wallis tests. Overall, antibiotic concentrations in effluent samples were lower than that of influent samples. Mid-Atlantic plants had similar influent but lower effluent antibiotic concentrations compared to Midwest plants. Azithromycin was detected at the highest concentrations (of all antibiotics) in influent and effluent samples from both regions. For most antibiotics, transport from the treatment plant to the irrigation site resulted in no changes in antibiotic concentrations, and UV treatment at the irrigation site had no effect on antibiotic concentrations in reclaimed water. Our findings show that low-level antibiotic concentrations persist in reclaimed water used for irrigation; however, the public health implications are unclear at this time. PMID:28635638

Dry-Enzyme Test For Gaseous Chemicals

NASA Technical Reports Server (NTRS)

Barzana, Eduardo; Karel, Marcus; Klibanov, Alexander

1990-01-01

Simple, dry-chemical test detects ethanol in human breath. Method of test also adapted to detection of such toxic chemicals as formaldehyde in airstreams. Used qualitatively to detect chemical compounds above present level; for example, ethanol above legal level for driving. Also used to indicate quantitatively concentrations of compounds. Involves dry enzyme and color indicator. Adapted to detect any gaseous compound transformed by enzymes to produce change evident to human eye or to instrument.

Progress In Fresnel-Köhler Concentrators

NASA Astrophysics Data System (ADS)

Mohedano, Rubén; Cvetković, Aleksandra; Benítez, Pablo; Chaves, Julio; Miñano, Juan C.; Zamora, Pablo; Hernandez, Maikel; Vilaplana, Juan

2011-12-01

The Fresnel Köhler (FK) concentrator was first presented in 2008. Since then, various CPV companies have adopted this technology as base for their future commercial product. The key for this rapid penetration is a mixture of simplicity (the FK is essentially a Fresnel lens concentrator, a technology that dominates the market) and excellent performance: high concentration without giving up large manufacturing/aiming tolerances, enabling high efficiency even at the array level. All these features together have a great potential to lower energy costs. This work shows recent results and progress regarding this device, covering new design features, measurements and tests along with first performance achievements at the array level (pilot 6.5 Kwp plant). The work also discusses the potential impact of the FK enhanced performance on the Levelized Cost Of Electricity (LCOE).

Forecasting model of Corylus, Alnus, and Betula pollen concentration levels using spatiotemporal correlation properties of pollen count.

PubMed

Nowosad, Jakub; Stach, Alfred; Kasprzyk, Idalia; Weryszko-Chmielewska, Elżbieta; Piotrowska-Weryszko, Krystyna; Puc, Małgorzata; Grewling, Łukasz; Pędziszewska, Anna; Uruska, Agnieszka; Myszkowska, Dorota; Chłopek, Kazimiera; Majkowska-Wojciechowska, Barbara

The aim of the study was to create and evaluate models for predicting high levels of daily pollen concentration of Corylus , Alnus , and Betula using a spatiotemporal correlation of pollen count. For each taxon, a high pollen count level was established according to the first allergy symptoms during exposure. The dataset was divided into a training set and a test set, using a stratified random split. For each taxon and city, the model was built using a random forest method. Corylus models performed poorly. However, the study revealed the possibility of predicting with substantial accuracy the occurrence of days with high pollen concentrations of Alnus and Betula using past pollen count data from monitoring sites. These results can be used for building (1) simpler models, which require data only from aerobiological monitoring sites, and (2) combined meteorological and aerobiological models for predicting high levels of pollen concentration.

Simultaneous Determination of Residue from 58 Pesticides in the Wheat Flour Consumed in Tehran, Iran by GC/MS

PubMed Central

Rezaei, Mohammad; Shariatifar, Nabi; Shoeibi, Shahram; Amir Ahmadi, Maryam; Jahed Khaniki, Gholamreza

2017-01-01

Food safety has a direct impact on human health and as such is a growing concern worldwide. Presence of harmful pesticide residue in food is a serious cause for concern among consumers so it is important to monitor levels of pesticides in foods. The aim of this study was simultaneous determination of concentrations of 58 pesticides in 40 wheat flour samples collected from Tehran market in January, 2014. The city under study (Tehran) was divided into five districts and samples were collected independently from each district and sourced from different bakeries (n=40). A gas chromatography-mass spectrometry single quadrupole selected ion monitoring «GC/MS-SQ-SIM» method was used to quantify residue of 58 pesticides in the wheat flour samples. Four of the 40 samples showed contamination with Malathion (2 samples: 50.96 ± 11.38 and 62.088 ± 11.38 ppb) and 2, 4-DDE (2 samples: 19.88±15.24 and 13.7 ± 15.24 ppb). that had levels below MRLs of these pesticides in Iran. Averages of recovery of pesticides at 6 concentration levels were in the range of 81.61-118.41%. The method was proven as repeatable with RSDr in the range of 6.5-29.45% for all concentration levels. The limit of quantification for 37 of the tested pesticides was calculated as 15 ppb and for the other 21 tested pesticides, the concentration was 25 ppb. In summary, results of these tests suggested that the wheat flour consumed in Tehran, was within safety limits in terms of levels of pesticide residues. PMID:29201093

Effects of methomyl on steroidogenic gene transcription of the hypothalamic-pituitary-gonad-liver axis in male tilapia.

PubMed

Meng, ShunLong; Qiu, LiPing; Hu, GengDong; Fan, LiMin; Song, Chao; Zheng, Yao; Wu, Wei; Qu, JianHong; Li, DanDan; Chen, JiaZhang; Xu, Pao

2016-12-01

Male tilapia were exposed to sub-lethal methomyl concentrations of 0, 0.2, 2, 20 or 200 μg/L for 30 d, and were subsequently cultured in methomyl-free water for 18 d. Relative transcript abundance of steroidogenic genes involved in the HPGL axis of male tilapia was examined at 30 d in the exposure test and at 18 d in the recovery test. The results revealed that low concentrations of methomyl (0.2 and 2 μg/L) did not cause significant changes in gene mRNA levels in the HPGL axis of male tilapia; thus, we considered 2 μg/L concentrations as the level that showed no apparent adverse endocrine disruption effects. However, higher concentrations of methomyl (20 and 200 μg/L) disrupted the endocrine system and caused significant increase in the levels of GnRH2, GnRH3, ERα, and ERβ genes in the hypothalamus, GnRHR and FSHβ genes in the pituitary, CYP19a, FSHR, and ERα genes in the testis, and VTG and ERα genes in the liver, and significantly decreased the levels of LHR, StAR, 3β-HSD, and ARα genes in the testis and LHβ gene in the pituitary, leading to changes in sex steroid hormone and vitellogenin levels in the serum and ultimately resulting in reproductive dysfunction in male tilapia. The recovery tests showed that the toxicity effect caused by 20 μg/L methomyl was reversible; however, the toxicity effect at 200 μg/L of methomyl was irreversible after 18 d. Therefore, we concluded that 200 μg/L was the threshold concentration for methomyl-induced irreversible endocrine disruption in male tilapia. Copyright © 2016 Elsevier Ltd. All rights reserved.

ACTUAL WASTE TESTING OF GYCOLATE IMPACTS ON THE SRS TANK FARM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martino, C.

2014-05-28

Glycolic acid is being studied as a replacement for formic acid in the Defense Waste Processing Facility (DWPF) feed preparation process. After implementation, the recycle stream from DWPF back to the high-level waste Tank Farm will contain soluble sodium glycolate. Most of the potential impacts of glycolate in the Tank Farm were addressed via a literature review and simulant testing, but several outstanding issues remained. This report documents the actual-waste tests to determine the impacts of glycolate on storage and evaporation of Savannah River Site high-level waste. The objectives of this study are to address the following: Determine the extentmore » to which sludge constituents (Pu, U, Fe, etc.) dissolve (the solubility of sludge constituents) in the glycolate-containing 2H-evaporator feed. Determine the impact of glycolate on the sorption of fissile (Pu, U, etc.) components onto sodium aluminosilicate solids. The first objective was accomplished through actual-waste testing using Tank 43H and 38H supernatant and Tank 51H sludge at Tank Farm storage conditions. The second objective was accomplished by contacting actual 2H-evaporator scale with the products from the testing for the first objective. There is no anticipated impact of up to 10 g/L of glycolate in DWPF recycle to the Tank Farm on tank waste component solubilities as investigated in this test. Most components were not influenced by glycolate during solubility tests, including major components such as aluminum, sodium, and most salt anions. There was potentially a slight increase in soluble iron with added glycolate, but the soluble iron concentration remained so low (on the order of 10 mg/L) as to not impact the iron to fissile ratio in sludge. Uranium and plutonium appear to have been supersaturated in 2H-evaporator feed solution mixture used for this testing. As a result, there was a reduction of soluble uranium and plutonium as a function of time. The change in soluble uranium concentration was independent of added glycolate concentration. The change in soluble plutonium content was dependent on the added glycolate concentration, with higher levels of glycolate (5 g/L and 10 g/L) appearing to suppress the plutonium solubility. The inclusion of glycolate did not change the dissolution of or sorption onto actual-waste 2H-evaporator pot scale to an extent that will impact Tank Farm storage and concentration. The effects that were noted involved dissolution of components from evaporator scale and precipitation of components onto evaporator scale that were independent of the level of added glycolate.« less

Toxicological assessment of concentrations of volatile organic compounds found in the ambient air of Seabrook, Texas and surrounding areas

NASA Astrophysics Data System (ADS)

Babin, Latrice Bundage

Seabrook, Texas, a residential community located in the southeast fringes of Houston, Texas, the fourth largest metropolis in the United States, is adjacent to a major industrial complex of petrochemical plants, chemical plants, refineries, hazardous materials storage facilities, and the intertwining of pipelines. The close proximity of residential communities to industrial complexes and their emission sources creates concern of the potential adverse health effects that could be a result of long-term exposure to Hazardous Air Pollutants (HAPs) even at low concentration. The purpose of this study is to assess the potential adverse health affects of low-level exposure of benzene, styrene, and 1, 1-dichloroethene that residents may experience. The case study utilized the screening data performed in a previous study conducted by the TSU NASA URC Laboratory. The sample results were compared to Texas Commission on Environmental Quality (TCEQ) guideline standards known as Effects Screening Levels (ESLs) to determine whether the ambient concentration levels were aligned with the TCEQ's pre-determined health cut off values. Special interest in the probable affects on lung epithelial cells and hepatic cells by the inhalation of benzene, styrene and 1,1-dichloroethene was examined by low level exposure (0.100ppm to 4ppm) of these chemicals for 4- and 6-hour exposure periods to determine whether the cells metabolic activity is adversely affected. Cytotoxicity of test chemicals was investigated utilizing MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide] assay protocol. Validation of the presence of benzene, styrene and 1,1-dichloroethene was performed by incubating a known dilution of the respective chemical for 4- and 6-hours to determine the approximate remaining concentration that should remain in the test media after the given exposure in the 37° incubator. Results of the study show little difference in the viability of the cells at the concentrations tested; however, there is evidence to indicate the benzene and styrene remained in the aqueous media and therefore provided a more toxic environment for both the lung and liver cells tested. The 1,1-dichloroethene was the most volatile of the chemicals tested and did not stabilize in the aqueous media well. Therefore, any exposure to the cells was made in the initial application of the chemical to the attached cell monolayer. The result of the case study revealed that although the concentration level exceeded the TCEQ ESL level for both short and long term exposure, a 4- and 6-hour exposures respectively, no significant adverse effect was observed in the cell lines used.

Serum neurotrophin concentrations in polish adolescent girls with anorexia nervosa.

PubMed

Dmitrzak-Weglarz, Monika; Skibinska, Maria; Slopien, Agnieszka; Tyszkiewicz, Marta; Pawlak, Joanna; Maciukiewicz, Małgorzata; Zaremba, Dorota; Rajewski, Andrzej; Hauser, Joanna

2013-01-01

Several lines of evidence suggest that brain-derived neurotrophic factor (BDNF) plays an important role in weight regulation and eating behaviors as well as in the activity-dependent neuroplasticity underlying learning and memory behaviors involving the hippocampus. In anorexia nervosa (AN) patients, abnormal serum BDNF concentrations, cognitive impairments and specific personality traits have been traditionally observed. This study explores the levels of four serum neurotrophins [BDNF, neurotrophin 3 (NTF3), neurotrophin 4 (NTF4) and glial cell line-derived neurotrophic factor (GDNF)] with respect to their use as potential biomarkers for AN. This study also investigates any associations that might exist between serum neurotrophin levels and neurocognitive impairment or personality traits. Serum neurotrophin concentrations were measured in 60 AN patients (AN group) and 45 healthy controls (HC group). We correlated the serum levels of the four neurotrophins BDNF, NTF3, NTF4 and GDNF and the clinical type of anorexia. We also analyzed the relationship between serum neurotrophin levels and the Beck Depression Inventory, body mass index, executive functions by the Wisconsin Card Sorting test (WCST) and personality dimensions by the Temperament and Character Inventory (TCI) test. Serum NTF4 concentrations were significantly lower when comparing all AN patients (34.7 ± 72.5 pg/ml) or restriction type AN patients (29.1 ± 62.5 pg/ml) with the HC group (58.4 ± 135.8 pg/ml; p = 0.004 and p = 0.005, respectively). A significant correlation (p < 0.005) between BDNF serum levels and patient personality dimensions as measured by the TCI test was observed. Furthermore, significant correlations were observed between NTF4 and GDNF serum levels and executive function as measured by the WCST. These data suggest that NTF4 might serve as a biomarker for AN. Furthermore, BDNF and GDNF serum levels appear to be associated with personality traits and executive function. Copyright © 2012 S. Karger AG, Basel.

Functional central hypothyroidism in the elderly.

PubMed

Sell, Maren A; Schott, Matthias; Tharandt, Lutz; Cissewski, Klaus; Scherbaum, Werner A; Willenberg, Holger S

2008-06-01

Previous studies have shown that blood concentrations of free thyroxin and basal thyroid-stimulating hormone (TSH) decrease during adult life. Suggested mechanisms include reduced thyroid activity resulting from decreased serum TSH concentrations, impairment of peripheral 5'-deiodinase, and an increase in reverse 3,5,3'-triiodothyronine due to non-thyroidal illness. However, testing of pituitary reserves leads to contradictory results and has infrequently been evaluated in studies. We investigated whether the response of TSH to thyrotropin-releasing hormone (TRH) is preserved during aging. This was tested in a cohort of 387 subjects aged 13 to 100 years in whom thyroid disease was excluded by normal thyroid ultrasound, normal values for free thyroxin, free triiodothyronin, TSH, and negative thyroid peroxidase antibodies. Serum concentrations of free thyroxin remained almost unchanged, whereas free triiodothyronin and TSH levels were lower in older subjects. In addition, the TSH response to TRH was blunted in older subjects, especially in male individuals. There is evidence that the decreased thyroid hormone levels observed in aging are due to lower TSH concentrations, and that lower TSH concentrations may be linked to an impaired pituitary activity.

The association between socio-demographic marginalization and plasma glucose levels at diagnosis of gestational diabetes.

PubMed

Sampson, L; Dasgupta, K; Ross, N A

2014-12-01

We examined the association between socio-demographic marginalization and plasma glucose levels at diagnosis of gestational diabetes in a multi-ethnic and socio-economically diverse patient group. Medical charts at a Toronto gestational diabetes clinic were reviewed for women with a recorded pregnancy between 1 March 2006 and 26 April 2011. One-hour 50-g glucose challenge test values and postal code data were abstracted. Postal codes were merged with 2006 Canadian census data to compute neighbourhood-level ethnic concentration (% recent immigrants, % visible minorities) and material deprivation (% low education, % low income, single-parent households). We compared women in the highest neighbourhood quintiles for both ethnic concentration and material deprivation with all other women to explore an association between marginalization and diagnostic glucose levels. Multivariate regression models of glucose challenge test values and insulin prescription were adjusted for age, prior gestational diabetes, parity and diabetes family history. Among 531 patients with complete glucose challenge test data (mean 11.94 mmol/l, sd 1.83), those in the most marginalized neighbourhoods had 0.43 mmol/l higher glucose challenge test values (95% CI 0.08-0.78) compared with the rest of the study population. Other factors associated with higher glucose challenge test values were prior gestational diabetes (0.59 mmol/l increment, 95% CI 0.19-0.99) and diabetes family history (0.32 mmol/l increment, 95% CI -0.01 to 0.66). Each additional 1 mmol/l glucose challenge test result was associated with an increased likelihood of being prescribed insulin (odds ratio 1.33, 95% CI 1.17-1.51). Women living in the most materially deprived and ethnically concentrated neighbourhoods have higher glucose levels at diagnosis of gestational diabetes. They may need close monitoring for timely initiation of insulin. © 2014 The Authors. Diabetic Medicine © 2014 Diabetes UK.

Cumulative exposure to lead and cognition in persons with Parkinson’s disease

PubMed Central

Weuve, Jennifer; Press, Daniel Z.; Grodstein, Francine; Wright, Robert O.; Hu, Howard; Weisskopf, Marc G.

2012-01-01

Background Dementia is an important consequence of Parkinson’s disease (PD), with few known modifiable risk factors. Cumulative exposure to lead, at levels experienced in the community, may exacerbate PD-related neural dysfunction, resulting in impaired cognition. Methods Among 101 persons with PD (“cases”) and, separately, 50 persons without PD (“controls”), we evaluated cumulative lead exposure, gauged via tibia and patella bone lead concentrations, in relation to cognitive function, assessed using a telephone battery developed and validated in a separate sample of PD patients. We also assessed the interaction between lead and case-control status. Results After multivariable adjustment, higher tibia bone lead concentration among PD cases was associated with worse performance on all of the individual telephone tests. In particular, tibia lead levels corresponded to significantly worse performance on a telephone analogue of the Mini-Mental State Examination and tests of working memory and attention. Moreover, higher tibia bone lead concentration was associated with significantly worse global composite score encompassing all the cognitive tests (P=0.04). The magnitude of association per standard deviation increment in tibia bone lead level was equivalent to the difference in global scores among controls in our study who were about seven years apart in age. The tibia lead-cognition association was notably stronger within cases than within controls (Pdifference=0.06). Patella bone lead concentration was not consistently associated with performance on the tests. Conclusions These data provide evidence suggesting that cumulative exposure to lead may result in worsened cognition among persons with PD. PMID:23143985

Cumulative exposure to lead and cognition in persons with Parkinson's disease.

PubMed

Weuve, Jennifer; Press, Daniel Z; Grodstein, Francine; Wright, Robert O; Hu, Howard; Weisskopf, Marc G

2013-02-01

Dementia is an important consequence of Parkinson's disease (PD), with few known modifiable risk factors. Cumulative exposure to lead, at levels experienced in the community, may exacerbate PD-related neural dysfunction, resulting in impaired cognition. Among 101 persons with PD ("cases") and, separately, 50 persons without PD ("controls"), we evaluated cumulative lead exposure, gauged by tibia and patella bone lead concentrations, in relation to cognitive function, assessed using a telephone battery developed and validated in a separate sample of PD patients. We also assessed the interaction between lead and case-control status. After multivariable adjustment, higher tibia bone lead concentration among PD cases was associated with worse performance on all of the individual telephone tests. In particular, tibia lead levels corresponded to significantly worse performance on a telephone analog of the Mini-Mental State Examination and tests of working memory and attention. Moreover, higher tibia bone lead concentration was associated with significantly worse global composite score encompassing all the cognitive tests (P = 0.04). The magnitude of association per standard deviation increment in tibia bone lead level was equivalent to the difference in global scores among controls in our study, who were approximately 7 years apart in age. The tibia lead-cognition association was notably stronger within cases than within controls (P(difference) = 0.06). Patella bone lead concentration was not consistently associated with performance on the tests. These data provide evidence suggesting that cumulative exposure to lead may result in worsened cognition among persons with PD. Copyright © 2012 Movement Disorders Society.

Noise suppression due to annulus shaping of conventional coaxial nozzle

NASA Technical Reports Server (NTRS)

Vonglahn, U.; Goodykoontz, J.

1980-01-01

A method which shows that increasing the annulus width of a conventional coaxial nozzle with constant bypass velocity will lower the noise level is described. The method entails modifying a concentric coaxial nozzle to provide an eccentric outer stream annulus while maintaining approximately the same through flow as that for the original concentric bypass nozzle. Acoustical tests to determine the noise generating characteristics of the nozzle over a range of flow conditions are described. The tests involved sequentially analyzing the noise signals and digitally recording the 1/3 octave band sound pressure levels. The measurements were made in a plane passing through the minimum and maximum annulus width points, as well as at 90 degrees in this plane, by rotating the outer nozzle about its axis. Representative measured spectral data in the flyover plane for the concentric nozzle obtained at model scale are discussed. Representative spectra for several engine cycles are presented for both the eccentric and concentric nozzles at engine size.

A COMPARISON OF WINTER SHORT-TERM AND ANNUAL AVERAGE RADON MEASUREMENTS IN BASEMENTS OF A RADON-PRONE REGION AND EVALUATION OF FURTHER RADON TESTING INDICATORS

PubMed Central

Barros, Nirmalla G.; Steck, Daniel J.; Field, R. William

2014-01-01

The primary objective of this study was to investigate the temporal variability between basement winter short-term (7 to 10 days) and basement annual radon measurements. Other objectives were to test the short-term measurement’s diagnostic performance at two reference levels and to evaluate its ability to predict annual average basement radon concentrations. Electret ion chamber (short-term) and alpha track (annual) radon measurements were obtained by trained personnel in Iowa residences. Overall, the geometric mean of the short-term radon concentrations (199 Bq m−3) was slightly greater than the geometric mean of the annual radon concentrations (181 Bq m−3). Short-term tests incorrectly predicted that the basement annual radon concentrations would be below 148 Bq m−3 12% of the time and 2% of the time at 74 Bq m−3. The short-term and annual radon concentrations were strongly correlated (r=0.87, p<0.0001). The foundation wall material of the basement was the only significant factor to have an impact on the absolute difference between the short-term and annual measurements. The findings from this study provide evidence of a substantially lower likelihood of obtaining a false negative result from a single short-term test in a region with high indoor radon potential when the reference level is lowered to 74 Bq m−3. PMID:24670901

Investigating Indoor Radon Levels and Influencing Factors in Primary Schools of Zulfi City, Saudi Arabia

NASA Astrophysics Data System (ADS)

Al-Ghamdi, S. S.; Al-Garawi, M. S.; Al-Mosa, Tahani M.; Baig, M. R.

2011-10-01

Measurement of indoor Concentrations were performed in Zulfi city of Saudi Arabia, using CR-39 track etch detectors. This investigation focused on the influence of different parameters, namely different locations, school categories, school building types, and room type as well as on the existence of differences in radon concentration at floor levels. We divided the Zulfi city into five regions, keeping in mind their geographical locations between Tuwaiq Mountains and Al-Thuwayrat sands. The measured average radon concentrations for regions 1-5 respectively are: 87.0±14.2 Bq/m3, 83.4±6.0 Bq/m3, 61.6±6.4 Bq/m3, 63.7±5.4 Bq/m3 and 87.5±6.Bq/m3 and the minimum concentrations are 28.0 Bq/m3, 5.5 Bq/m3, 1.1 Bq/m3, 1.0 Bq/m3 and 24 Bq/m3 respectively. These results are still within normal limits and below the action level of 148 Bqm-3 set by the U.S. Environmental Protection Agency (EPA). A test of significance using Minitab program was applied to investigate if radon levels in regions are significantly different from each other. We tried all combinations, and found the following results. The "within regions" (different location) test yielded, region 2 is not significant versus region "1" (p = 0.783) and versus region "5" (P = 0.646), whereas it is significant versus region "3" ( P = 0.0160) and also versus region "4" (p = 0.018). We investigated government and rented school's building also and none was found significantly different (p = 0.052). Floors of the same building were tested in order to examine the radon concentration as a function of storey level. No significant difference was observed at floor levels (p = 0.009). When girl's schools versus Boys and kindergartens schools were tested they were found significantly different. It is believed that this significant difference is due to geographical nature of the area, since most of the girl's schools were selected from regions 2 and 3, these regions are relatively close to the Tuwaiq mountains whereas other regions are near to the Al-Thuwayrat sands.

Temporal variations of 90Sr and 137Cs concentrations in Japanese coastal surface seawater and sediments from 1974 to 1998

NASA Astrophysics Data System (ADS)

Ikeuchi, Yoshihiro

2003-09-01

90Sr and 137Cs concentrations were determined in surface water and bottom sediments collected at 11 sites offshore from Japan during the period 1974-1998, to investigate their temporal variations and behaviour in the coastal marine environment. The concentrations of 90Sr and 137Cs in surface water have decreased with time since 1974. After the period of atmospheric nuclear weapons tests, the mean residence times of 90Sr and 137Cs were about 41 and 51 years, respectively. The 137Cs/ 90Sr activity ratios in coastal seawater during the atmospheric nuclear weapons tests (up until 1980) were lower than those after the tests due to the inflow of 90Sr in river water. A sharp increase in 137Cs levels was observed in airborne dust, in precipitation on the Japanese islands, and in coastal surface seawater in 1986 following the Chernobyl accident. However, the 137Cs levels in surface water returned to pre-1986 levels quickly, indicating rapid removal of Cs from the surface to deeper water. Concentrations of 90Sr in sediments were generally much lower than those for 137Cs, reflecting the more effective scavenging of Cs from the water column. In Ca-rich sediments, consisting of corals and shells, higher 90Sr levels and 90Sr/ 137Cs activity ratios were found, reflecting higher accumulation of Sr than Cs in marine organisms. Higher accumulation of 90Sr than 137Cs was also found in seaweed (gulfweed and wakame).

Correlation of Oxygenated Hemoglobin Concentration and Psychophysical Amount on Speech Recognition

NASA Astrophysics Data System (ADS)

Nozawa, Akio; Ide, Hideto

The subjective understanding on oral language understanding task is quantitatively evaluated by the fluctuation of oxygenated hemoglobin concentration measured by the near-infrared spectroscopy. The English listening comprehension test wihch consists of two difficulty level was executed by 4 subjects during the measurement. A significant correlation was found between the subjective understanding and the fluctuation of oxygenated hemoglobin concentration.

Performance Comparison of Field Portable Instruments to the Scanning Mobility Particle Sizer Using Monodispersed and Polydispersed Sodium Chloride Aerosols.

PubMed

Vo, Evanly; Horvatin, Matthew; Zhuang, Ziqing

2018-05-21

This study compared the performance of the following field portable aerosol instrument sets to performance of the reference Scanning Mobility Particle Sizer (SMPS): the handheld CPC-3007, the portable aerosol mobility spectrometer (PAMS), the NanoScan scanning mobility particle sizer (NanoScan SMPS) combined with an optical particle sizer (OPS). Tests were conducted with monodispersed and polydispersed aerosols. Monodispersed aerosols were controlled at the approximate concentration of 1 × 105 particles cm-3 and four monodispersed particle sizes of 30, 60, 100, and 300 nm were selected and classified for the monodispersed aerosol test, while three different steady-state concentration levels (low, medium, and high: ~8 × 103, 5 × 104, and 1 × 105 particles cm-3, respectively) were selected for the polydispersed aerosol test. For all four monodispersed aerosol sizes, particle concentrations measured with the NanoScan SMPS were within 13% of those measured with the reference SMPS. Particle concentrations measured with the PAMS were within 25% of those measured with the reference SMPS. Concentrations measured with the handheld condensation particle counter were within 30% of those measured with the reference SMPS. For the polydispersed aerosols, the particle sizes and concentrations measured with the NanoScan-OPS compared most favorably with those measured with the reference SMPS for three different concentration levels of low, medium, and high (concentration deviations ≤10% for all three concentration levels; deviations of particle size ≤4%). Although the particle-size comparability between the PAMS and the reference SMPS was quite reasonable with the deviations within 10%, the polydispersed particle concentrations measured with the PAMS were within 36% of those measured with the reference SMPS. The results of this evaluation will be useful for selecting a suitable portable device for our next workplace study phase of respiratory protection assessment. This study also provided the advantages and limitations of each individual portable instrument and therefore results from this study can be used by industrial hygienists and safety professionals, with appropriate caution, when selecting a suitable portable instrument for aerosol particle measurement in nanotechnology workplaces.

Influence of chloride on the chronic toxicity of sodium nitrate to Ceriodaphnia dubia and Hyalella azteca.

PubMed

Soucek, David J; Dickinson, Amy

2016-09-01

While it has been well established that increasing chloride concentration in water reduces the toxicity of nitrite to freshwater species, little work has been done to investigate the effect of chloride on nitrate toxicity. We conducted acute and chronic nitrate (as sodium nitrate) toxicity tests with the cladoceran Ceriodaphnia dubia and the amphipod Hyalella azteca (chronic tests only) over a range of chloride concentrations spanning natural chloride levels found in surface waters representative of watersheds of the Great Lakes Region. Chronic nitrate toxicity test results with both crustaceans were variable, with H. azteca appearing to be one of the more sensitive invertebrate species tested and C. dubia being less sensitive. While the variability in results for H. azteca were to an extent related to chloride concentration in test water that was distinctly not the case for C. dubia. We concluded that the chloride dependent toxicity of nitrate is not universal among freshwater crustaceans. An additional sodium chloride chronic toxicity test with the US Lab strain of H. azteca in the present study suggested that when present as predominantly sodium chloride and with relatively low concentrations of other ions, there is a narrow range of chloride concentrations over which this strain is most fit, and within which toxicity test data are reliable.

Activity levels of tamoxifen metabolites at the estrogen receptor and the impact of genetic polymorphisms of phase I and II enzymes on their concentration levels in plasma.

PubMed

Mürdter, T E; Schroth, W; Bacchus-Gerybadze, L; Winter, S; Heinkele, G; Simon, W; Fasching, P A; Fehm, T; Eichelbaum, M; Schwab, M; Brauch, H

2011-05-01

The therapeutic effect of tamoxifen depends on active metabolites, e.g., cytochrome P450 2D6 (CYP2D6) mediated formation of endoxifen. To test for additional relationships, 236 breast cancer patients were genotyped for CYP2D6, CYP2C9, CYP2B6, CYP2C19, CYP3A5, UGT1A4, UGT2B7, and UGT2B15; also, plasma concentrations of tamoxifen and 22 of its metabolites, including the (E)-, (Z)-, 3-, and 4'-hydroxymetabolites as well as their glucuronides, were quantified using liquid chromatography-tandem mass spectrometry (MS). The activity levels of the metabolites were measured using an estrogen response element reporter assay; the strongest estrogen receptor inhibition was found for (Z)-endoxifen and (Z)-4-hydroxytamoxifen (inhibitory concentration 50 (IC50) 3 and 7 nmol/l, respectively). CYP2D6 genotypes explained 39 and 9% of the variability of steady-state concentrations of (Z)-endoxifen and (Z)-4-hydroxytamoxifen, respectively. Among the poor metabolizers, 93% had (Z)-endoxifen levels below IC90 values, underscoring the role of CYP2D6 deficiency in compromised tamoxifen bioactivation. For other enzymes tested, carriers of reduced-function CYP2C9 (*2, *3) alleles had lower plasma concentrations of active metabolites (P < 0.004), pointing to the role of additional pathways.

Use of anti-Müllerian hormone testing during ovarian reserve screening to identify women at risk of polycystic ovary syndrome.

PubMed

Safier, Lauren Z; Grossman, Lisa C; Chan, Cariann W; Sauer, Mark V; Lobo, Rogerio A; Douglas, Nataki C

2016-10-01

To assess the applicability of anti-Müllerian hormone (AMH) testing in the identification of women at risk for polycystic ovary syndrome (PCOS) when AMH is used in ovarian reserve screening in the general population. A secondary analysis was undertaken of a large cross-sectional study. Women aged 27-37years, presently delaying childbearing but interested in future fertility, completed an online questionnaire to assess knowledge and attitudes about ovarian reserve testing, and underwent serum AMH testing between October 2014 and April 2015 in New York, NY, USA. For the secondary analysis, women considered to have elevated AMH levels (≥4.7ng/mL) were invited for physical examination and transvaginal ultrasonography. Among 97 women who underwent AMH testing, 32 (33.0%) had elevated AMH levels. Hyperandrogenism was reported by 8 (25.0%) women with elevated AMH and none with AMH concentrations lower than 4.7ng/mL (P<0.001). Irregular menstrual cycles before hormonal contraceptive use were reported by 16 (24.6%) of 65 women with AMH concentrations lower than 4.7ng/mL and 11 (34.4%) with elevated AMH (P=0.34). Of the 20 women with elevated AMH who returned for further evaluation, 16 (80.0%) had polycystic ovaries and 13 (65.0%) were diagnosed with PCOS (Rotterdam criteria). When AMH levels are used as a screening test for fertility, elevated concentrations can identify women at risk for PCOS. Copyright © 2016 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

Comparison of Pumped and Diffusion Sampling Methods to Monitor Concentrations of Perchlorate and Explosive Compounds in Ground Water, Camp Edwards, Cape Cod, Massachusetts, 2004-05

USGS Publications Warehouse

LeBlanc, Denis R.; Vroblesky, Don A.

2008-01-01

Laboratory and field tests were conducted at Camp Edwards on the Massachusetts Military Reservation on Cape Cod to examine the utility of passive diffusion sampling for long-term monitoring of concentrations of perchlorate and explosive compounds in ground water. The diffusion samplers were constructed of 1-inch-diameter rigid, porous polyethylene tubing. The results of laboratory tests in which diffusion samplers were submerged in containers filled with ground water containing perchlorate, RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine), and HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) indicate that concentrations inside the diffusion samplers equilibrated with concentrations in the containers within the 19-day-long test period. Field tests of the diffusion samplers were conducted in 15 wells constructed of 2- or 2.5-inch-diameter polyvinyl chloride pipe with 10-foot-long slotted screens. Concentrations of perchlorate, RDX, and HMX in the diffusion samplers placed in the wells for 42 to 52 days were compared to concentrations in samples collected by low-flow pumped sampling from 53 days before to 109 days after retrieval of the diffusion samples. The results of the field tests indicate generally good agreement between the pumped and diffusion samples for concentrations of perchlorate, RDX, and HMX. The concentration differences indicate no systematic bias related to contaminant type or concentration levels.

40 CFR 798.4350 - Inhalation developmental toxicity study.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) HEALTH EFFECTS TESTING GUIDELINES Specific Organ/Tissue... million (ppm). (6) “No-observed-effect level” is the maximum concentration in a test which produces no observed adverse effects. A no-observed-effect level is expressed in terms of weight or volume of test...

40 CFR 798.4350 - Inhalation developmental toxicity study.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) HEALTH EFFECTS TESTING GUIDELINES Specific Organ/Tissue... million (ppm). (6) “No-observed-effect level” is the maximum concentration in a test which produces no observed adverse effects. A no-observed-effect level is expressed in terms of weight or volume of test...

40 CFR 798.4350 - Inhalation developmental toxicity study.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) TOXIC SUBSTANCES CONTROL ACT (CONTINUED) HEALTH EFFECTS TESTING GUIDELINES Specific Organ/Tissue... million (ppm). (6) “No-observed-effect level” is the maximum concentration in a test which produces no observed adverse effects. A no-observed-effect level is expressed in terms of weight or volume of test...

Cow-level association between serum 25-hydroxyvitamin D concentration and Mycobacterium avium subspecies paratuberculosis antibody seropositivity: a pilot study.

PubMed

Sorge, U S; Molitor, T; Linn, J; Gallaher, D; Wells, S W

2013-02-01

Vitamin D deficiency has been associated with various human diseases. Therefore, the objective of this study was to evaluate the cow-level association between serum 25-hydroxyvitamin D [25(OH)D] concentration and Mycobacterium avium ssp. paratuberculosis (MAP) seropositivity of dairy cows, adjusting for diet, breed, hair coat color, stage of lactation, reproductive status, and cow age. The sera of 80 MAP antibody ELISA-positive and 80 test-negative herd mates from 5 Minnesota dairy herds were analyzed for 25(OH)D and 1,25-dihydroxyvitamin D [1,25(OH)(2)D]. The cows' age, production records, and hair coat color were recorded. Additionally, feed samples were obtained and analyzed for vitamin D(2) and vitamin D(3) content. A linear mixed model was used to identify potential predictors for serum 25(OH)D concentration, accounting for herd of origin. The majority of rations analyzed had over 22,000 IU of vitamin D/day (maximum: 52,000 I U/d) and the study cows' average serum 25(OH)D concentration was 62.5 ± 13.8 ng/mL. Serum ELISA-positive cows had, on average, 5.3 ng/mL lower 25(OH)D serum levels than test-negative herd mates. The reproductive status of cows was also associated with the 25(OH)D levels, with fresh cows having the lowest serum concentration. In this cross-sectional study, a temporal or causal association between MAP antibody ELISA status and serum 25(OH)D concentration could not be evaluated. In addition, the high levels of vitamin D in the rations of participating farms and the average 25(OH)D serum concentration suggest that additional supplementation with vitamin D in the ration is likely to be ineffective. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of Two Cancer Chemotherapeutic Agents on the Antibacterial Activity of Three Antimicrobial Agents

PubMed Central

Moody, Marcia R.; Morris, Maureen J.; Young, Viola Mae; Moyé, Lemuel A.; Schimpff, Stephen C.; Wiernik, Peter H.

1978-01-01

Cancer chemotherapeutic agents and antibacterial antibiotics are often given concomitantly. Daunorubicin, cytosine arabinoside, and three antibiotics (gentamicin, amikacin, and ticarcillin) were tested individually and in combinations to determine their antimicrobial activity against Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli. These cytotoxic agents are commonly employed in the therapy of acute nonlymphocytic leukemia for remission induction therapy, and these antimicrobial agents are used in infection therapy. The maximum concentrations of the two cytotoxic drugs were chosen to be twice the known peak plasma levels of commonly employed dosage schedules. Neither of the cancer chemotherapeutic agents, alone or in combination, demonstrated bactericidal activity at the levels tested. However, in the presence of these agents, the antimicrobial activity of gentamicin and amikacin, although not that of ticarcillin, was depressed for 11 of 15 K. pneumoniae strains and 8 of 15 P. aeruginosa strains, but for none of the strains of E. coli. This level of decreased activity occasionally resulted in a minimal inhibitory concentration of the tested aminoglycoside well above the standard serum levels. Daunorubicin was more likely to antagonize gentamicin than was cytosine arabinoside. PMID:103494

Module Measurements | Photovoltaic Research | NREL

Science.gov Websites

prototype concentrator evaluation test bed, and the Daystar DS-10/125 portable I-V curve tracer. Standard Evaluation Test Bed. We developed this test bed to be able to evaluate I-V characteristics throughout the day a function of time, temperature, and light level. This test bed data set is also used to evaluate

Competitive-level differences in Yo-Yo intermittent recovery and twelve minute run test performance in soccer referees.

PubMed

Castagna, Carlo; Abt, Grant; D'Ottavio, Stefano

2005-11-01

The aim of this study was to examine yo-yo intermittent recovery test (Yo-Yo test) and 12-minute run test (12MRT) performances in experienced soccer referees of different competitive levels. Three groups (n = 14 each) of experienced Italian soccer referees officiating in the first (series AB, top-level), third (series C, medium-level), and fourth (series D, low-level) division, were randomly submitted to the 12MRT and the Yo-Yo test during 2 testing sessions, 48-hours apart. 12MRT performances were 3,000 +/- 112 m; 2,894 +/- 99 m; and 2,896 +/- 171 m for top-level, medium-level and low-level referees, respectively (p > 0.05). In the Yo-Yo test, the top-level, medium-level, and low-level referees covered 1,874 +/- 431 m; 1,360 +/- 172 m; and 1,272 +/- 215 m, respectively. The test performances of top-level referees in the Yo-Yo test was significantly different from those scored by medium-level and low-level referees (p < 0.05). After the Yo-Yo test, blood lactate concentrations (BLC) were higher in the medium-level and low-level referees compared with the top-level referees (p < 0.05). The results of the present study show that the Yo-Yo test and not the 12MRT can discriminate endurance performance in experienced elite level soccer referees. With respect to its discriminative and match performance validity, the Yo-Yo test may be considered a relevant field test to assess endurance preparedness for experienced soccer referees and a useful tool in talent selection.

A statistical approach to investigating enhancement of polonium-210 in the Eastern Irish Sea arising from discharges from a former phosphate processing plant.

PubMed

Dewar, Alastair; Camplin, William; Barry, Jon; Kennedy, Paul

2014-12-01

Since the cessation of phosphoric acid production (in 1992) and subsequent closure and decommissioning (2004) of the Rhodia Consumer Specialties Limited plant in Whitehaven, the concentration levels of polonium-210 ((210)Po) in local marine materials have declined towards a level more typical of natural background. However, enhanced concentrations of (210)Po and lead-210 ((210)Pb), due to this historic industrial activity (plant discharges and ingrowth of (210)Po from (210)Pb), have been observed in fish and shellfish samples collected from this area over the last 20 years. The results of this monitoring, and assessments of the dose from these radionuclides, to high-rate aquatic food consumers are published annually in the Radioactivity in Food and the Environment (RIFE) report series. The RIFE assessment uses a simple approach to determine whether and by how much activity is enhanced above the normal background. As a potential tool to improve the assessment of enhanced concentrations of (210)Po in routine dose assessments, a formal statistical test, where the null hypothesis is that the Whitehaven area is contaminated with (210)Po, was applied to sample data. This statistical, modified "green", test has been used in assessments of chemicals by the OSPAR commission. It involves comparison of the reported environmental concentrations of (210)Po in a given aquatic species against its corresponding Background Assessment Concentration (BAC), which is based upon environmental samples collected from regions assumed to be not enhanced by industrial sources of (210)Po, over the period for which regular monitoring data are available (1990-2010). Unlike RIFE, these BAC values take account of the variability of the natural background level. As an example, for 2010 data, crab, lobster, mussels and winkles passed the modified "green" test (i.e. the null hypothesis is rejected) and as such are deemed not to be enhanced. Since the cessation of phosphoric acid production in 1992, the modified "green" test pass rate for crustaceans is ∼53% and ∼64% for molluscs. Results of dose calculations are made (i) using the RIFE approach and (ii) with the application of the modified "green" test, where samples passing the modified "green" test are assumed to have background levels and hence zero enhancement of (210)Po. Applying the modified "green" test reduces the dose on average by 44% over the period of this study (1990-2010). Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

Evaluation of micron size carbon fibers released from burning graphite composites

NASA Technical Reports Server (NTRS)

Sussholz, B.

1980-01-01

Quantitative estimates were developed of micron carbon fibers released during the burning of graphite composites. Evidence was found of fibrillated particles which were the predominant source of the micron fiber data obtained from large pool fire tests. The fibrillation phenomena were attributed to fiber oxidation effects caused by the fire environment. Analysis of propane burn test records indicated that wind sources can cause considerable carbon fiber oxidation. Criteria estimates were determined for the number of micron carbon fibers released during an aircraft accident. An extreme case analysis indicated that the upper limit of the micron carbon fiber concentration level was only about half the permissible asbestos ceiling concentration level.

NO2/NO partitioning as a test of stratospheric ClO concentrations over Antarctica

NASA Technical Reports Server (NTRS)

Webster, Christopher R.

1987-01-01

Physical conditions in the 10-20 km region of the Antarctic stratosphere make the (NO2)/(NO) ratio particularly sensitive to high chlorine levels in the form of ClO. According to simple known photochemical relationships between NO2, NO, ClO, and O3, high ClO levels of 1 ppbv over Antarctica must be accompanied by large values of the (NO2)/(NO) ratio. At high ClO abundances, the (NO2)/(NO) ratio is approximately proportional to the ClO concentration. It is proposed that in-situ measurements of the (NO2)/(NO) ratio could be used to test the high chlorine hypothesis.

Variability in the blood/breath alcohol ratio and implications for evidentiary purposes.

PubMed

Jaffe, Dena H; Siman-Tov, Maya; Gopher, Asher; Peleg, Kobi

2013-09-01

The breath analyzer is an indispensable tool for identifying alcohol levels among drivers. While numerous studies have shown high correlations between blood and breath alcohol concentrations, most are limited by the study design. This study seeks to assess this relationship by minimizing potential measurement bias, document time from alcohol consumption to testing, and adjusting for potential confounders. A blinded study was performed using conditions closely resembling those in the field. The Draeger 7110 MKIII IL breath analyzer was used to assess breath alcohol concentrations (BrAC). Participants were 61 healthy volunteers aged 21-37 years with body mass index ≤30 and no history of alcoholism. A total of 242 valid blood/breath tests were performed in four test sets. The study results showed a high correlation coefficient between BrAC and blood alcohol concentration (BAC) levels (r = 0.983) with high sensitivity (97%) and specificity (93%). This strong association between the breath analyzer and BAC persisted even after adjustment for various stages of alcohol absorption. These results illustrate the high diagnostic sensitivity of the breath analyzer in field-tested conditions. © 2013 American Academy of Forensic Sciences.

Geographical mapping of fluoride levels in drinking water sources in Nigeria.

PubMed

Akpata, Enosakhare S; Danfillo, I S; Otoh, E C; Mafeni, J O

2009-12-01

Knowledge of fluoride levels in drinking water is of importance in dental public health, yet this information is lacking, at national level, in Nigeria. To map out fluoride levels in drinking water sources in Nigeria. Fluoride levels in drinking water sources from 109 randomly selected Local Government Areas (LGAs) in the 6 Nigerian geopolitical zones were determined. From the results, maps showing LGAs with fluoride concentrations exceeding 0.3 ppm, were drawn. ANOVA and t-test were used to determine the significance of the differences between the fluoride levels in the drinking water sources. Fluoride levels were low in most parts of the country, being 0.3 ppm or less in 62% of the LGAs. Fluoride concentrations were generally higher in North Central geopolitical zone, than the other zones in the country (p<0.05). In a few drinking water sources, fluoride concentrations exceeded 1.5 ppm, but was as high as 6.7 ppm in one well. Only 9% of the water sources were from waterworks. Most of the water sources in Nigeria contained low fluoride levels; but few had excessive concentrations and need to be partially defluoridated, or else alternative sources of drinking water provided for the community.

Initial Test Bed for Very High Efficiency Solar Cells

DTIC Science & Technology

2008-05-01

efficiency, both at the solar cell and module levels. The optical system consists of a tiled nonimaging concentrating system, coupled with a spectral...Benítez, P. (2005). Nonimaging Optics . Boston: Elsevier Academic Press. [6] Luque, A.L. & Andreev, V.M. (2007). Concentrator Photovoltaics. New York: Springer. ...lateral optical concentrating system, which splits the incident solar spectrum into several bands and allows different optical and photovoltaic

Influence of bismuth oxide concentration on the pH level and biocompatibility of white Portland cement.

PubMed

Marciano, Marina Angélica; Garcia, Roberto Brandão; Cavenago, Bruno Cavalini; Minotti, Paloma Gagliardi; Midena, Raquel Zanin; Guimarães, Bruno Martini; Ordinola-Zapata, Ronald; Duarte, Marco Antonio Hungaro

2014-01-01

To investigate if there is a relation between the increase of bismuth oxide and the decrease of pH levels and an intensification of toxicity in the Portland cement. White Portland cement (WPC) was mixed with 0, 15, 20, 30 and 50% bismuth oxide, in weight. For the pH level test, polyethylene tubes were filled with the cements and immersed in Milli-Q water for 15, 30 and 60 days. After each period, the increase of the pH level was assessed. For the biocompatibility, two polyethylene tubes filled with the cements were implanted in ninety albino rats (n=6). The analysis of the intensity of the inflammatory infiltrate was performed after 15, 30 and 60 days. The statistical analysis was performed using the Kruskal-Wallis, Dunn and Friedman tests for the pH level and the Kruskal-Wallis and Dunn tests for the biological analysis (p<0.05). The results showed an increase of the pH level after 15 days, followed by a slight increase after 30 days and a decrease after 60 days. There were no significant statistical differences among the groups (p>0.05). For the inflammatory infiltrates, no significant statistical differences were found among the groups in each period (p>0.05). The 15% WPC showed a significant decrease of the inflammatory infiltrate from 15 to 30 and 60 days (p<0.05). The addition of bismuth oxide into Portland cement did not affect the pH level and the biological response. The concentration of 15% of bismuth oxide resulted in significant reduction in inflammatory response in comparison with the other concentrations evaluated.

An optical spot test for the detection of dopamine in human urine using stabilized in air lipid films.

PubMed

Nikolelis, Dimitrios P; Drivelos, Dimitrios A; Simantiraki, Maria G; Koinis, Spyros

2004-04-15

The present technique describes a simple, sensitive spot test for the rapid one-shot detection of dopamine in human urine using lipid films with incorporated resorcin[4]arene receptor that are synthesized by a chemical reaction with a methacrylate polymer on a glass fiber filter. The lipid films without the receptor provided fluorescence under a UV lamp. The use of the receptor in these films quenched this fluorescence, and the color became similar to that of the filters without the lipid films. A drop of dopamine or urine containing this stimulant provided a "switching on" of the fluorescence, which allows the rapid detection of this stimulant in human urine at 10(-8) M concentrations. The novelty of the present work is that it opens new routes in the field of biosensing, i.e., development of sensitive, rapid, and simple methods for detecting species based on the fluorescence of the lipid membranes on a polymer film, and provides a spot test technique for the rapid detection of dopamine. The effect of potent interferences including a wide range of compounds usually found in human urine (i.e., ascorbic aid, glucose, leucine, glycine, tartrate, citrate, bicarbonate, and caffeine) was examined using an aqueous buffered solution that contained the potent interference and dopamine at two lower concentration levels (i.e., 3 x 10(-8)-10(-8) M). The effect of proteins and lipids was also investigated at these two lower dopamine concentration levels in aqueous buffered solution. The results showed no interferences from all these constituents at concentrations usually found in human urine samples; for example, albumin up to 3.22 g/L concentration levels did not provide any interference (i.e., no fluorescence). A drop of urine containing this stimulant provided similar results, i.e., a "switching on" of the fluorescence that allows a technique for the rapid detection of this stimulant in human urine at 10(-8) M concentrations. The technique is not based on a calibration graph but is a semiquantitative method for the detection of dopamine in real samples of urine that can be complimentary to HPLC methods. The difference in color between the samples containing dopamine at concentration levels of 10(-8)-10(-7) M can be easily distinguished by naked eye and a digital camera. An increase of dopamine concentration from 10(-8) to 10(-7) M makes the color more blue whereas the color of the filters remains purple in the blank test (i.e., addition of a urine sample without dopamine or dopamine at concentration levels of 10(-9) M to the filters that contain the lipid membranes with incorporated receptor). The reproducibility of the method was checked in approximately 100 samples, and all of them were found to provide similar results. Note that it was also found that the colors remain stable in the samples containing dopamine for periods of more than two months.

Naphthalene emissions from moth repellents or toilet deodorant blocks determined using head-space and small-chamber tests.

PubMed

Jo, Wan-Kuen; Lee, Jong-Hyo; Lim, Ho-Jin; Jeong, Woo-Sik

2008-01-01

The present study investigated the emissions of naphthalene and other compounds from several different moth repellents (MRs) and one toilet deodorant block (TDB) currently sold in Korea, using a headspace analysis. The emission factors and emission rates of naphthalene were studied using a small-scale environmental chamber. Paper-type products emitted a higher concentration of the total volatile organic compounds (VOCs) (normalized to the weight of test piece) than ball-type products, which in turn emitted higher concentration than a gel-type product. In contrast, naphthalene was either the most or the second highest abundant compound for the four ball products, whereas for paper and gel products it was not detected or was detected at much lower levels. The abundance of naphthalene ranged between 18.4% and 37.3% for ball products. The results showed that the lower the air changes per hour (ACH) level was, the higher the naphthalene concentrations became. In general, a low ACH level suggests a low ventilation rate. The emission factor for naphthalene was nearly 100 times higher for a ball MR than for a gel or a paper MR. For the ball MR, the lower ACH level resulted in higher emission rate.

Effect of light and atmosphere on the cultivation of the golden oyster culinary-medicinal mushroom, Pleurotus citrinopileatus (higher Basidiomycetes).

PubMed

Hu, Shu-Hui; Wu, Chiu-Yeh; Chen, Yu-Kuei; Wang, Jinn-Chyi; Chang, Sue-Joan

2013-01-01

With an aim to explore the productivity and quality of the fruiting body of culinary-medicinal golden oyster mushroom Pleurotus citrinopileatus, the carbon dioxide (CO₂) concentration of the ambient atmosphere was adjusted and a light-emitting diode panel was used to illuminate the colonized mycelium at different wavelengths. Biological efficiency and yield were higher at CO₂ levels of 0.05 and 0.1% than other tested CO₂ levels, and the mature fruiting body showed the highest yellow value at a CO₂ level of 0.1% (of all tested CO₂ levels). The highest biological efficiency and yield was obtained at the 720-nm wavelength. The ergosterol content of the pileus of the fruiting body was higher than that of the stipe in any flush time at a 720-nm wavelength of light and a CO₂ concentration of 0.1%. The decreased percentages of cellulose and lignin at the appearance of primordia were larger than those of mycelial growth duration. The fruiting quality of P. citrinopileatus might thus be enhanced by 720-nm illumination and an atmosphere with a CO₂ concentration of 0.1 to 0.15%.

Loss on drying, calcium concentration and pH of fluoride dentifrices

PubMed Central

Brito, Arella Cristina Muniz; Dantas, Lívia Rocha; De Brito, André Luiz Fiquene; Muniz, Ana Cristina Silva; Ramos, Ianny Alves; Cardoso, Andreia Medeiros Rodrigues; Xavier, Alidianne Fábia Cabral; Cavalcanti, Alessandro Leite

2015-01-01

Introduction: Fluoride dentifrices containing calcium carbonate have advantages such as control of dental plaque and progression of dental caries, also contributing to oral hygiene, represent most dentifrices marketed in Brazil. Aim: To evaluate the physicochemical properties of seven fluoride dentifrices containing calcium carbonate in relation to hydrogen potential (pH), loss on drying and calcium concentration. Materials and Methods: Data collection was performed using the potentiometric method for pH ranges, gravimetric analysis for loss on drying and atomic absorption spectrometry for the concentration of calcium ions. All tests were performed in triplicate and the analysis was performed entirely at random according to one-way analysis of variance at 5% significance level. Results: The pH values were alkaline and ranged from 8.67 (Oral-B 123®) to 10.03 (Colgate Máxima Proteção Anticáries®). The results of loss on drying ranged from 33.81% (Oral-B 123®) to 61.13% (Close Up®), with significant differences between brands tested. In relation to the calcium content, the highest and lowest concentrations were found in dentifrices Even® (155.55 g/kg) and Colgate Ultra Branco® (129 g/kg), respectively, with significant difference (P < 0.05). Conclusion: Fluoride dentifrices analyzed showed alkaline pH and high levels of loss on drying and calcium concentration. However, these physicochemical characteristics differed according to the different brands tested. PMID:25821380

Confirmation of elevated arsenic levels in groundwater of Myanmar

PubMed Central

van Geen, Alexander; Win, Kyi Htut; Zaw, Than; Naing, Win; Mey, Jacob L.; Mailloux, Brian

2014-01-01

Millions of villagers across South and Southeast Asia are exposed to toxic levels of arsenic (As) by drinking well water. In order to confirm field-kit results that Myanmar is also affected, a total of 55 wells were tested in the field in January 2013 and sampled for laboratory analysis across seven villages spanning a range of As contamination in the lower Ayeyarwady basin. Elevated concentrations of As (50–630 μg/L) were measured in wells up to 60 m deep and associated with high levels of Fe (up to 21 mg/L) and low concentrations of SO4 (<0.05 mg/L). Concentrations of As <10 μg/L were measured in some shallow (<30 m) grey sands and in both shallow and deep orange sands. These results indicate that the main mechanism of As release to groundwater in Myanmar is the reductive dissolution of Fe oxyhydroxides, as in the neighboring Bengal, Mekong, and Red River basins. Concentrations of As in groundwater of Myanmar are therefore unlikely to change rapidly over time and switching to existing low-As wells is a viable way of reducing exposure in the short term. However, only 17 of the 55 well owners interviewed correctly recalled the status of their well despite extensive testing in the region. A renewed effort is thus needed to test existing wells and new wells that continue to be installed and to communicate the health risks of exposure to As for infants, children, and adults. PMID:24530581

Serum levels of fatty acid binding protein 4 and fat metabolic markers in relation to catecholamines following exercise.

PubMed

Iso, Tatsuya; Sunaga, Hiroaki; Matsui, Hiroki; Kasama, Shu; Oshima, Naomi; Haruyama, Hikari; Furukawa, Nozomi; Nakajima, Kiyomi; Machida, Tetsuo; Murakami, Masami; Yokoyama, Tomoyuki; Kurabayashi, Masahiko

2017-11-01

Lipolysis is stimulated by activation of adrenergic inputs to adipose tissues. Our recent study showed that serum concentrations of fatty acid binding protein 4 (FABP4) are robustly elevated in patients with acute myocardial infarction and ventricular tachyarrhythmia, that display a marked activation of the sympathetic nervous system (SNS). However, it remains unknown whether circulating FABP4 concentrations are associated with exercise-induced SNS activation. Thirty one healthy volunteers underwent cardiopulmonary exercise testing on a cycle ergometer up to the workload levels below and above anaerobic threshold, low- and high-intensity exercise, respectively. Serial blood samplings were performed before and after exercise. High-intensity exercise significantly increased serum concentrations of FABP4 and catecholamines, and their concentrations declined fast thereafter in a similar fashion. These changes were accompanied by little, if any, changes in other metabolic markers. Regardless of adiposity, percent change from baseline to peak FABP4 levels (%FABP4) was comparable in all subjects. Stepwise regression analysis revealed that %FABP4 was highly correlated with that in norepinephrine. Our study reveals the significant correlation between circulating FABP4 and norepinephrine levels during exercise testing. Together with the fact that FABP4 is secreted from adipocytes via β-adrenergic-mediated lipolytic mechanisms, this study suggests FABP4 as a potential biomarker for adrenergic overdrive. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Elevated serum homocysteine level is not associated with serum C-reactive protein in patients with probable Alzheimer's disease.

PubMed

Lepara, Orhan; Alajbegovic, Azra; Zaciragic, Asija; Nakas-Icindic, Emina; Valjevac, Amina; Lepara, Dzenana; Hadzovic-Dzuvo, Almira; Fajkic, Almir; Kulo, Aida; Sofic, Emin

2009-12-01

Elevated plasma homocysteine (Hcy) levels have been associated with Alzheimer's disease (AD) and cognitive impairment. Studies have shown that Hcy may have direct and indirect neurotoxicity effects. The aim of the study was to investigate serum Hcy concentration in patients with probable AD with age-matched controls and to determine whether there was an association between serum Hcy and C-reactive protein concentration in patients with probable AD. We also aimed to determine whether there was an association between serum tHcy concentration and cognitive impairment in patients with probable AD. Serum concentration of total Hcy was determined by the fluorescence polarization immunoassay on the AxSYM system, and serum C-reactive protein (CRP) concentration was determined by means of particle-enhanced immunonephelometry with the use of BN II analyzer. Cognitive impairment was tested by the MMSE score. Body mass index (BMI) was calculated for each subject included in the study. Age, systolic and diastolic blood pressure and BMI did not differ significantly between the two groups. Mean serum tHcy concentration in the control group of subjects was 12.60 mumol/L, while in patients with probable AD the mean serum tHcy concentration was significantly higher than 16.15 mumol/L (p < 0.01). A significant negative association between serum tHcy concentration and cognitive impairment tested by the MMSE score in patients with probable AD was determined (r = -0.61634; p < 0.001). Positive, although not significant correlation between CRP and serum tHcy concentrations in patients with AD, was observed. Increased tHcy concentration in patients with probable AD, and the established negative correlation between serum tHcy concentration and cognitive damage tested by MMSE score in the same group of patients, suggests the possible independent role of Hcy in the pathogenesis of AD and cognitive impairment associated with this disease.

Serum concentrations of soluble (s)L- and (s)P-selectins in women with ovarian cancer.

PubMed

Majchrzak-Baczmańska, Dominika B; Głowacka, Ewa; Wilczyński, Miłosz; Malinowski, Andrzej

2018-03-01

The aim of the study was to compare serum concentration of soluble L- and P-selectins in women with ovarian cancer (OC) and healthy controls, and to investigate sL- and sP-selectin levels with regard to clinical and pathological parameters. Correlation analysis was used to measure the following: sL- and sP-selectin concentration and Ca125; sP-selectin and platelet concentrations; and sL-selectin and serum leukocyte levels in women with OC. The study included 29 patients with OC and 23 healthy controls. Serum concentrations of sL- and sP-selectins were measured in all subjects. Routine diagnostic tests: CBC and USG (both groups) and Ca125 (study group) were performed. Significantly higher serum concentrations of sL- and sP-selectins were found in the study group as compared to controls. Lower levels of serum sL-selectin were observed in women with poorly-differentiated OC (G3) and advanced stages of the disease (FIGO III, IV), but the results were statistically insignificant. No statistically significant relationship was detected between sP-selectin serum concentration in women with OC and tumour differentiation, histological type, and stage of the disease. No significant correlation was found between sL- and sP-selectins and Ca125 levels. A weak correlation was found between serum concentration of sP-selectin in women with OC and platelet count. No statistically significant correlation was observed between sL-selectin concentration and serum leukocyte levels in women with OC. The analysis of sL- and sP-selectin concentrations may be a useful tool in the diagnosis of OC. The levels of sL-selectin decrease with disease progression.

Predicting ground level impacts of solid rocket motor testing

NASA Technical Reports Server (NTRS)

Douglas, Willard L.; Eagan, Ellen E.; Kennedy, Carolyn D.; Mccaleb, Rebecca C.

1993-01-01

Beginning in August of 1988 and continuing until the present, NASA at Stennis Space Center, Mississippi has conducted environmental monitoring of selected static test firings of the solid rocket motor used on the Space Shuttle. The purpose of the study was to assess the modeling protocol adapted for use in predicting plume behavior for the Advanced Solid Rocket Motor that is to be tested in Mississippi beginning in the mid-1990's. Both motors use an aluminum/ammonium perchlorate fuel that produces HCl and Al2O3 particulates as the major combustion products of concern. A combination of COMBUS.sr and PRISE.sr subroutines and the INPUFF model are used to predict the centerline stabilization height, the maximum concentration of HCl and Al2O3 at ground level, and distance to maximum concentration. Ground studies were conducted to evaluate the ability of the model to make these predictions. The modeling protocol was found to be conservative in the prediction of plume stabilization height and in the concentrations of the two emission products predicted.

Concentrations of metals and trace elements in blood of spectacled and king eiders in northern Alaska, USA

USGS Publications Warehouse

Wilson, Heather M.; Petersen, Margaret R.; Troy, Declan

2004-01-01

In 1996, we measured concentrations of arsenic, barium, cadmium, lead, mercury, and selenium in blood of adult king (Somateria spectabilis) and spectacled (Somateria fischeri) eiders and duckling spectacled eiders from northern Alaska, USA. Concentrations of selenium exceeded background levels in all adults sampled and 9 of 12 ducklings. Mercury was detected in all adult spectacled eiders and 5 of 12 ducklings. Lead concentrations were above the clinical toxicity threshold in one duckling (0.64 ppm) and two adult female spectacled eiders (0.54 and 4.30 ppm). Concentrations of cadmium and mercury varied between species; barium, cadmium, mercury, and selenium varied between sexes. In female spectacled eiders, mercury concentrations increased during the breeding season and barium and selenium levels decreased through the breeding season. Selenium declined at 2.3 ± 0.9% per day and levels were lower in spectacled eiders arriving to the breeding grounds in northern Alaska than in western Alaska. The variation in selenium levels between breeding areas may be explained by differences in timing and routes of spring migration. Most trace elements for which we tested were not at levels currently considered toxic to marine birds. However, the presence of mercury and elevated lead in ducklings and adult female spectacled eiders suggests these metals are available on the breeding grounds.

Differential expression of lactic acid isomers, extracellular matrix metalloproteinase inducer, and matrix metalloproteinase-8 in vaginal fluid from women with vaginal disorders.

PubMed

Beghini, J; Linhares, I M; Giraldo, P C; Ledger, W J; Witkin, S S

2015-11-01

Do metabolites in vaginal samples vary between women with different vaginal disorders. Cross-sectional study. Campinas, Brazil. Seventy-seven women (39.9%) with no vaginal disorder, 52 women (26.9%) with vulvovaginal candidiasis (VVC), 43 women (22.3%) with bacterial vaginosis (BV), and 21 women (10.9%) with cytolytic vaginosis (CTV). Concentrations of D- and L-lactic acid, extracellular matrix metalloproteinase inducer (EMMPRIN), and matrix metalloproteinase-8 (MMP-8), and the influence of Candida albicans on EMMPRIN production by cultured vaginal epithelial cells, were determined by enzyme-linked immunosorbent assay (ELISA). Associations were determined by the Mann-Whitney U-test and by Spearman's rank correlation test. Metabolite levels and their correlation with diagnoses. Vaginal concentrations of D- and L-lactic acid were reduced from control levels in BV (P < 0.0001); L-lactic acid levels were elevated in CTV (P = 0.0116). EMMPRIN and MMP-8 concentrations were elevated in VVC (P < 0.0001). EMMPRIN and L-lactic acid concentrations (P ≤ 0.008), but not EMMPRIN and D-lactic acid, were correlated in all groups. EMMPRIN also increased in proportion with the ratio of L- to D-lactic acid in controls and in women with BV (P ≤ 0.009). Concentrations of EMMPRIN and MMP-8 were correlated in controls and women with VVC (P ≤ 0.0002). Candida albicans induced EMMPRIN release from vaginal epithelial cells. Vaginal secretions from women with BV are deficient in D- and L-lactic acid, women with VVC have elevated EMMPRIN and MMP-8 levels, and women with CTV have elevated L-lactic acid levels. These deviations may contribute to the clinical signs, symptoms, and sequelae that are characteristic of these disorders. © 2014 Royal College of Obstetricians and Gynaecologists.

RESEARCH REPORT: USE OF VEGETATIVE VIGOR TEST TO DETECT EFFECTS OF LOW LEVELS OF HERBICIDES ON SELECTED NON-CROP PLANTS

EPA Science Inventory

To address the need for improved phytotoxicity testing protocols, we evaluated use of the vegetative vigor test methodology for use in determining effects of low concentrations of chemical herbicides on terrestrial non-crop plant species. Species included native plants from Illi...

Weakening of ion-channel interactions of Na+ and Li+ in acetylcholine-receptor channels of frog skeletal muscle with an increase in agonist concentration.

PubMed

Manthey, A A

1998-05-01

The possibility that increases in agonist concentration beyond threshold levels may force changes in the character of high-conductance open states of skeletal muscle nicotinic acetylcholine receptor channels (nAChR) was examined by seeing whether differences in several critical ionic properties of nAChR currents could be detected with changes in agonist level. Single- and bi-ionic whole-cell currents of Na+ and Li+ in voltage-clamped frog (Rana pipiens) muscle fibers were measured during local superfusion of endplates with carbamylcholine (carb) at concentrations of 54 microm (low-carb) and 270 microM (high-carb). Three ionic properties that would be affected by changes in the open-state configuration of channel subunits were tested. First, ion-saturation characteristics. Peak Na+ and Li+ currents in low-carb trials showed sublinear dependence on ion concentrations from 0 to 60 mM with Km values of 78 (Na+) and 49 (Li+) mM and a power function slope of 0. 75 on double-log plot. In contrast, the concentration dependence of Na+ and Li+ currents in high-carb tests was linear through the origin with a power function slope of 1.02. Second, Na+/Li+ selectivity. The ratio of peak Na+ and Li+ currents in low-carb tests varied from 1.86 to 2.28 for ion concentrations of from 20 to 60 mM [mean = 2.02 +/- 0.06 (SEM)] whereas the ratio for high-carb trials ranged from only 1.29 to 1.52 [mean = 1.42 +/- 0.40 (SEM)]. Third, competitive interactions of Na+ and Li+ currents. Equimolar mixtures of Na+ and Li+ in low-carb tests produced bi-ionic inward currents which were never larger than the single-ion Na+ current alone, but bi-ionic currents at the high-carb level were always greater than the single-ion Na+ current, approximating the sum of the single-ion Na+ and Li+ currents in most cases. The results are consistent with a decrease in ion-channel binding at the high-carb level and support the possibility of agonist-induced changes in the high-conductance open-state configuration of nAChR subunits which result in a weakening of constraints on cation movements through the channel.

The ecological competition and grazing reverse the effects of sulfamethoxazole on plankton: a case study on characterizing community-level effect.

PubMed

Wang, Changyou; Liang, Shengkang; Zhang, Yong

2018-04-12

The toxic effects of sulfamethoxazole (SMX) on densities of two algae, Platymonas helgolandica var. tsingtaoensis, Isochrysis galbana, and of a rotifer, Brachionus plicatilis, were tested by the population and community experiments. Two endpoints, the carrying capacity and the densities array of community in steady state (DACS), were used to characterize the toxic effects at a population level and a community one, respectively. The results showed that the carrying capacity of P. helgolandica var. tsingtaoensis and B. plicatilis did not decline significantly in population test when the concentration of SMX was lower than 6.0 mg L -1 and 12.0 mg L -1 , respectively. However, I. galbana was sensitive to SMX and had presented toxic effect at 3.0 mg L -1 . By extrapolation of toxic effect at a population level to a community one, a derived community-NOEC was 3.0 mg L -1 , representing an inference from data of toxic effects at population level. In community experiment, when the customized community was in steady state, the density of I. galbana increased as a whole with SMX concentration in the range of tested concentration (0-144 mg L -1 ), while that of P. helgolandica var. tsingtaoensis assumed the trend of a reversed "v" in this range. Only the density of B. plicatilis decreased with SMX concentration. With the DACS as endpoint, a NOEC for the customized community was determined to be 6.0 mg L -1 . This indicates that interspecific interactions can reverse the toxic effects of SMX on phytoplankton. The DACS was reliable and stable, serving as the endpoints in assessment of the effects of the pollutants on the ecosystems.

Design Characteristics and Tobacco Metal Concentrations in Filtered Cigars.

PubMed

Caruso, Rosalie V; O'Connor, Richard J; Travers, Mark J; Delnevo, Cristine D; Stephens, W Edryd

2015-11-01

While U.S. cigarette consumption has declined, cigar use has steadily increased, for reasons including price compared to cigarettes and the availability of filtered varieties resembling cigarettes, and flavors that have been banned in cigarettes (excluding menthol). Little published data exists on the design characteristics of such cigars. A variety of filtered cigar brands were tested for design characteristics such as whole cigar weight, ventilation, and per-cigar tobacco weight. Cigar sticks were then sent to the University of St. Andrews for metal concentration testing of As, Pb, Cr, Ni, and Cd. Large and small cigars were statistically different between cigar weight (p ≤ .001), per-cigar tobacco weight (p = .001), rod diameter (p = .006), and filter diameter (p = .012). The differences in mean ventilation (overall mean = 19.6%, min. = 0.84%, max. = 57.6%) across filtered cigar brands were found to be statistically significant (p = .031), and can be compared to the ventilation of the average of 2013 U.S. Marlboro Red, Gold, and Silver packs at 29% ventilation. There were no significant differences for metal concentrations between cigar types (p = .650), with Pb and As levels being similar to U.S. 2009 cigarette concentrations, Cd cigar levels being slightly higher, and Cr and Ni levels much lower than cigarette levels. With cigar use rising, and filtered cigars displaying substantial similarities to filtered cigarettes, more research on product characteristics is warranted. Future plans include testing tobacco alkaloid and more observation of cigar weight for tax bracket purposes. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The sky is falling II: Impact of deposition produced during the static testing of solid rocket motors on corn and alfalfa.

PubMed

Doucette, William J; Mendenhall, Scout; McNeill, Laurie S; Heavilin, Justin

2014-06-01

Tests of horizontally restrained rocket motors at the ATK facility in Promontory, Utah, USA result in the deposition of an estimated 1.5million kg of entrained soil and combustion products (mainly aluminum oxide, gaseous hydrogen chloride and water) on the surrounding area. The deposition is referred to as test fire soil (TFS). Farmers observing TFS deposited on their crops expressed concerns regarding the impact of this material. To address these concerns, we exposed corn and alfalfa to TFS collected during a September 2009 test. The impact was evaluated by comparing the growth and tissue composition of controls relative to the treatments. Exposure to TFS, containing elevated levels of chloride (1000 times) and aluminum (2 times) relative to native soils, affected the germination, growth and tissue concentrations of various elements, depending on the type and level of exposure. Germination was inhibited by high concentrations of TFS in soil, but the impact was reduced if the TFS was pre-leached with water. Biomass production was reduced in the TFS amended soils and corn grown in TFS amended soils did not develop kernels. Chloride concentrations in corn and alfalfa grown in TFS amended soils were two orders of magnitude greater than controls. TFS exposed plants contained higher concentrations of several cations, although the concentrations were well below livestock feed recommendations. Foliar applications of TFS had no impact on biomass, but some differences in the elemental composition of leaves relative to controls were observed. Washing the TFS off the leaves lessened the impact. Results indicate that the TFS deposition could have an effect, depending on the amount and growth stage of the crops, but the impact could be mitigated with rainfall or the application of additional irrigation water. The high level of chloride associated with the TFS is the main cause of the observed impacts. Copyright © 2014 Elsevier B.V. All rights reserved.

Association between neurotrophin 4 and long-chain polyunsaturated fatty acid levels in mid-trimester amniotic fluid.

PubMed

Benn, Kiesha; Passos, Mariana; Jayaram, Aswathi; Harris, Mary; Bongiovanni, Ann Marie; Skupski, Daniel; Witkin, Steven S

2014-11-01

The omega-3 long-chain polyunsaturated fatty acid (LCPUFA) docosahexaenoic acid (DHA) and the omega-6 LCPUFA arachidonic acid (AA) are essential nervous system components that increase in concentration throughout gestation. The neurotrophins, brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin 3 (NT3), and neurotrophin 4 (NT4) are small basic peptides crucial for fetal brain development. The DHA supplementation during pregnancy has been suggested to enhance neural development. We evaluated whether amniotic fluid DHA and AA concentrations correlated with intra-amniotic neurotrophin levels. Amniotic fluid, obtained at 15 to 19 weeks gestation from 62 women, was tested for BDNF, NGF, NT3, and NT4 by enzyme-linked immunosorbent assay. Concentrations of DHA and AA, and saturated and monounsaturated fatty acids, were determined by gas chromatography. Associations were analyzed by the Spearman rank correlation test. Median levels of AA and DHA were 2.3% and 1.3% of the total intra-amniotic fatty acids, respectively. Median neurotrophin levels (pg/mL) were 36.7 for NT3, 26.8 for BDNF, 5.2 for NT4, and 0.8 for NGF. Intra-amniotic NT4 and BDNF levels were correlated (P = .0016), while NT3 and NGF levels were unrelated to each other or to BDNF or NT4. Only NT4 was positively correlated with amniotic fluid DHA (P < .0001) and AA (P = .0003) concentrations. There were no associations between DHA, AA, or any neurotrophin and maternal age, gestational age at time of amniocentesis, amniocentesis indication, parity, or gestational age at delivery. Elevations in intra-amniotic NT4 with increasing levels of DHA and AA suggest that these LCPUFAs may specifically influence the extent of NT4-mediated fetal brain neurogenesis. © The Author(s) 2014.

Emodin opposes chronic unpredictable mild stress induced depressive-like behavior in mice by upregulating the levels of hippocampal glucocorticoid receptor and brain-derived neurotrophic factor.

PubMed

Li, Meng; Fu, Qiang; Li, Ying; Li, Shanshan; Xue, Jinsong; Ma, Shiping

2014-10-01

Emodin, the major active component of Rhubarb, has shown neuroprotective activity. This study is attempted to investigate whether emodin possesses beneficial effects on chronic unpredictable mild stress (CUMS)-induced behavioral deficits (depression-like behaviors) and explore the possible mechanisms. ICR mice were subjected to chronic unpredictable mild stress for 42 consecutive days. Then, emodin and fluoxetine (positive control drug) were administered for 21 consecutive days at the last three weeks of CUMS procedure. The classical behavioral tests: open field test (OFT), sucrose preference test (SPT), tail suspension test (TST) and forced swimming test (FST) were applied to evaluate the antidepressant effects of emodin. Then plasma corticosterone concentration, hippocampal glucocorticoid receptor (GR) and brain-derived neurotrophic factor (BDNF) levels were tested to probe the mechanisms. Our results indicated that 6 weeks of CUMS exposure induced significant depression-like behavior, with high, plasma corticosterone concentration and low hippocampal GR and BDNF expression levels. Whereas, chronic emodin (20, 40 and 80 mg/kg) treatments reversed the behavioral deficiency induced by CUMS exposure. Treatment with emodin normalized the change of plasma corticosterone level, which demonstrated that emodin could partially restore CUMS-induced HPA axis impairments. Besides, hippocampal GR (mRNA and protein) and BDNF (mRNA) expressions were also up-regulated after emodin treatments. In conclusion, emodin remarkably improved depression-like behavior in CUMS mice and its antidepressant activity is mediated, at least in part, by the up-regulating GR and BDNF levels in hippocampus. Copyright © 2014 Elsevier B.V. All rights reserved.

Receptor activator of nuclear factor kappa B ligand and osteoprotegerin levels in gingival crevicular fluid

PubMed Central

Sarlati, Fatemeh; Sattari, Mandana; Razzaghi, Shilan; Nasiri, Malihe

2012-01-01

Background: Osteoclastogenesis is coordinated by the interaction of three members of the tumor necrosis factor (TNF) superfamily: Osteoprotegerin (OPG)/receptor activator of nuclear factor kappa B ligand (RANKL)/receptor activator of nuclear factor kappa B (RANK). The aim of this study was to investigate RANKL and OPG levels, and their relative ratio in gingival crevicular fluid (GCF) of patients with chronic and aggressive periodontitis, as well as healthy controls. Materials and Methods: In this analytical study, GCF was obtained from healthy (n = 10), mild chronic periodontitis (n = 18), moderate chronic periodontitis (n = 18), severe chronic periodontitis (n = 20), and generalized aggressive periodontitis (n = 20) subjects. RANKL and OPG concentrations were measured by enzyme-linked immunosorbent assay. Statistical tests used were Kruskal–Wallis test, Mann–Whitney U rank sum test, and Spearman's rank correlation analysis. The level of statistical significance was set at P < 0.05. Results: Mean RANKL concentration showed no statistically significant differences between groups (P = 0.58). There were also no significant differences between mean OPG concentration in the five groups (P = 0.0.56). Moreover, relative RANKL/OPG ratio did not reveal a significant difference between the three study group subjects: healthy, chronic periodontitis (mild, moderate, severe), and aggressive periodontitis (P = 0.41). There was statistically significant correlation between the concentration of sRANKL and Clinical Attachment Level (CAL) in moderate chronic periodontitis patients (R = 0.48, P = 0.04). There was also negative correlation between OPG concentration and CAL in moderate chronic periodontitis patients, although not significant (R = −0.13). Conclusion: RANKL was prominent in periodontitis sites, especially in moderate periodontitis patients, whereas OPG was not detectable in some diseased sites with bleeding on probing, supporting the role of these two molecules in the bone loss developed in this disease. PMID:23559954

Data Concentrator

NASA Technical Reports Server (NTRS)

Willett, Mike

2015-01-01

Orbital Research, Inc., developed, built, and tested three high-temperature components for use in the design of a data concentrator module in distributed turbine engine control. The concentrator receives analog and digital signals related to turbine engine control and communicates with a full authority digital engine control (FADEC) or high-level command processor. This data concentrator follows the Distributed Engine Controls Working Group (DECWG) roadmap for turbine engine distributed controls communication development that operates at temperatures at least up to 225 C. In Phase I, Orbital Research developed detailed specifications for each component needed for the system and defined the total system specifications. This entailed a combination of system design, compiling existing component specifications, laboratory testing, and simulation. The results showed the feasibility of the data concentrator. Phase II of this project focused on three key objectives. The first objective was to update the data concentrator design modifications from DECWG and prime contractors. Secondly, the project defined requirements for the three new high-temperature, application-specific integrated circuits (ASICs): one-time programmable (OTP), transient voltage suppression (TVS), and 3.3V. Finally, the project validated each design by testing over temperature and under load.

An evaluation of the toxicity of potassium chloride, active compound in the molluscicide potash, on salmonid fish and their forage base

USGS Publications Warehouse

Densmore, Christine L.; Iwanowicz, Luke R.; Henderson, Anne P.; Blazer, Vicki S.; Reed-Grimmett, Baileigh M.; Sanders, Lakyn R.

2018-06-29

Potash, with the active ingredient potassium chloride (KCl) is a chemical that is currently being evaluated for potential use as a molluscicide to combat invasive zebra mussels and quagga mussels in Western United States waters. Although data available for other freshwater fishes indicate that recommended treatment levels of potash as a molluscicide are sublethal, this has not been demonstrated for all salmonid species. The objectives of this study were to perform toxicity testing to determine the lethality of potassium chloride against selected species of salmonid fish (brook trout and Chinook salmon) and selected invertebrate forage, and to identify any potential adverse physiological impacts of KCl to these salmonids in water at treatment levels used for mollusk eradication. Minimal mortality (n=1 fish) was observed during 96-hour toxicity testing at KCl concentrations of 0 to 800 milligrams per liter (mg/L), indicating that the lethal concentration (LC50) values in these salmonid species were considerably higher than realistic molluscicide treatment concentrations. Sublethal effects were examined through evaluation of behavioral and morphological (histological) observation as well as specific blood chemistry parameters (electrolytes, osmolality, glucose, and cortisol). There was no strong evidence of significant physiological impairment among the two salmonid species due to KCl exposure. Whereas statistically significant differences in some parameters were observed in association with KCl treatments, it is unlikely that these differences indicate adverse biological impacts. Acute toxicity tests were conducted with invertebrate species at KCl exposure concentrations of 0–3,200 mg/L. Daphniid exposure trials resulted in differences in mortality among the test groups with higher mortality evident among the higher KCl exposure concentrations with a calculated LC50 value of 196 mg/L KCl for a 48-hour exposure. Crayfish exposed to higher concentrations of KCl at or above 800 mg/L as specimens exhibited death or reversible paralysis. Chironomid larvae exposures were largely inconclusive because of cannibalistic behavior among the various test groups.

Association between posttest dexamethasone and cortisol concentrations in the 1 mg overnight dexamethasone suppression test.

PubMed

Asvold, Bjørn O; Grill, Valdemar; Thorstensen, Ketil; Bjørgaas, Marit R

2012-11-01

It has been suggested that comparison of posttest dexamethasone and cortisol concentrations may improve the evaluation of the dexamethasone suppression test (DST) for Cushing's syndrome. In particular, this would be reasonable if posttest cortisol differs by dexamethasone levels within the range that is usually attained in the DST. Using fractional polynomial regression, we therefore studied the association between posttest 0800 h dexamethasone and cortisol levels in 53 subjects without Cushing's syndrome who were tested with the 1 mg overnight DST. Plasma dexamethasone was associated with plasma cortisol (P<0.001), and the regression line suggested a strong negative association related to dexamethasone levels <5 nmol/l. However, among the 94% of subjects with plasma dexamethasone >5.0 nmol/l, there was no association between dexamethasone and cortisol levels (P=0.55). In conclusion, subjects tested with the 1 mg overnight DST usually attain an 0800 h plasma dexamethasone >5 nmol/l, and plasma cortisol does not differ by plasma dexamethasone in these subjects. This suggests that routine comparison of dexamethasone and cortisol levels may not be a useful approach to improve the performance of the 1 mg DST. However, dexamethasone measurements may identify subjects with inadequately low plasma dexamethasone and may therefore be of value when retesting subjects with possibly false-positive DST results.

Association between posttest dexamethasone and cortisol concentrations in the 1 mg overnight dexamethasone suppression test

PubMed Central

Åsvold, Bjørn O; Grill, Valdemar; Thorstensen, Ketil; Bjørgaas, Marit R

2012-01-01

It has been suggested that comparison of posttest dexamethasone and cortisol concentrations may improve the evaluation of the dexamethasone suppression test (DST) for Cushing's syndrome. In particular, this would be reasonable if posttest cortisol differs by dexamethasone levels within the range that is usually attained in the DST. Using fractional polynomial regression, we therefore studied the association between posttest 0800 h dexamethasone and cortisol levels in 53 subjects without Cushing's syndrome who were tested with the 1 mg overnight DST. Plasma dexamethasone was associated with plasma cortisol (P<0.001), and the regression line suggested a strong negative association related to dexamethasone levels <5 nmol/l. However, among the 94% of subjects with plasma dexamethasone >5.0 nmol/l, there was no association between dexamethasone and cortisol levels (P=0.55). In conclusion, subjects tested with the 1 mg overnight DST usually attain an 0800 h plasma dexamethasone >5 nmol/l, and plasma cortisol does not differ by plasma dexamethasone in these subjects. This suggests that routine comparison of dexamethasone and cortisol levels may not be a useful approach to improve the performance of the 1 mg DST. However, dexamethasone measurements may identify subjects with inadequately low plasma dexamethasone and may therefore be of value when retesting subjects with possibly false-positive DST results. PMID:23781306

Potential supplementary utility of combined PFA-100 and functional von Willebrand factor testing for the laboratory assessment of desmopressin and factor concentrate therapy in von Willebrand disease.

PubMed

Favaloro, Emmanuel J; Thom, Jim; Patterson, David; Just, Sarah; Baccala, Maria; Dixon, Tracy; Meiring, Muriel; Koutts, Jerry; Rowell, John; Baker, Ross

2009-09-01

We performed a retrospective audit of cross-laboratory testing of desmopressin and factor concentrate therapy to assess the potential utility of supplementary testing using the PFA-100 with functional von Willebrand factor (VWF) activity testing. Data were evaluated for a large number of patients with von Willebrand disease of type 1, type 2A or type 2M, as well as a comparative subset of individuals with haemophilia or carriers of haemophilia. Laboratory testing comprised pre and postdesmopressin, or pre and postconcentrate, evaluation of factor VIII, VWF antigen (VWF:Ag) and VWF ristocetin cofactor activity as traditionally performed, supplemented with collagen-binding (VWF:CB) testing and PFA-100 closure times. In brief, both therapies tended to normalize VWF test parameters and closure times in individuals with type 1 von Willebrand disease, with the level of correction in closure times related to the level of normalization of VWF, particularly the VWF:CB. However, although occasional correction of closure times was observed in patients with type 2A or type 2M von Willebrand disease, these did not in general normalize PFA-100 closure times either with desmopressin or factor concentrate therapy. In these patients, improvement in closure times was more likely in those in whom VWF:CB values normalized or when VWF:CB/VWF:Ag ratios normalized. This study confirms that there is a strong relationship between the presenting levels of plasma VWF and PFA-100 closure times, and that the supplementary combination of PFA-100 and VWF:CB testing might provide added clinical utility to current broadly applied testing strategies limited primarily to VWF:Ag, VWF ristocetin cofactor and factor VIII:coagulant. Future prospective investigations are warranted to validate these relationships and to investigate their therapeutic implications.

Effects of sediment characteristics on the toxicity of chromium(III) and chromium(VI) to the amphipod, Hyalella azteca

USGS Publications Warehouse

Besser, J.M.; Brumbaugh, W.G.; Kemble, N.E.; May, T.W.; Ingersoll, C.G.

2004-01-01

We evaluated the influence of sediment characteristics, acid-volatile sulfide (AVS) and organic matter (OM), on the toxicity of chromium (Cr) in freshwater sediments. We conducted chronic (28-42-d) toxicity tests with the amphipod Hyalella azteca exposed to Cr(VI) and Cr(III) in water and in spiked sediments. Waterborne Cr(VI) caused reduced survival of amphipods with a median lethal concentration (LC50) of 40 ??g/L. Cr(VI) spiked into test sediments with differing levels of AVS resulted in graded decreases in AVS and sediment OM. Only Cr(VI)-spiked sediments with low AVS concentrations (<1 ??mol/g) caused significant amphipod mortality. Waterborne Cr(III) concentrations near solubility limits caused decreased survival of amphipods at pH 7 and pH 8 but not at pH 6. Sediments spiked with high levels of Cr(III) did not affect amphipod survival but had minor effects on growth and inconsistent effects on reproduction. Pore waters of some Cr(III)-spiked sediments contained measurable concentrations of Cr(VI), but observed toxic effects did not correspond closely to Cr concentrations in sediment or pore waters. Our results indicate that risks of Cr toxicity are low in freshwater sediments containing substantial concentrations of AVS.

Simulated Waste Testing Of Glycolate Impacts On The 2H-Evaporator System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martino, C. J.

2013-08-13

Glycolic acid is being studied as a total or partial replacement for formic acid in the Defense Waste Processing Facility (DWPF) feed preparation process. After implementation, the recycle stream from DWPF back to the high-level waste tank farm will contain soluble sodium glycolate. Most of the potential impacts of glycolate in the tank farm were addressed via a literature review, but several outstanding issues remained. This report documents the non-radioactive simulant tests impacts of glycolate on storage and evaporation of Savannah River Site high-level waste. The testing for which non-radioactive simulants could be used involved the following: the partitioning ofmore » glycolate into the evaporator condensate, the impacts of glycolate on metal solubility, and the impacts of glycolate on the formation and dissolution of sodium aluminosilicate scale within the evaporator. The following are among the conclusions from this work: Evaporator condensate did not contain appreciable amounts of glycolate anion. Of all tests, the highest glycolate concentration in the evaporator condensate was 0.38 mg/L. A significant portion of the tests had glycolate concentration in the condensate at less than the limit of quantification (0.1 mg/L). At ambient conditions, evaporator testing did not show significant effects of glycolate on the soluble components in the evaporator concentrates. Testing with sodalite solids and silicon containing solutions did not show significant effects of glycolate on sodium aluminosilicate formation or dissolution.« less

Microbial Challenge Testing of Single Liquid Cathode Feed Water Electrolysis Cells for the International Space Station (ISS) Oxygen Generator Assembly (OGA)

NASA Technical Reports Server (NTRS)

Roy, Robert J.; Wilson, Mark E.; Diderich, Greg S.; Steele, John W.

2011-01-01

The International Space Station (ISS) Oxygen Generator Assembly (OGA) operational performance may be adversely impacted by microbiological growth and biofilm formation over the electrolysis cell membranes. Biofilms could hinder the transport of water from the bulk fluid stream to the membranes and increase the cell concentration overpotential resulting in higher cell voltages and a shorter cell life. A microbial challenge test was performed on duplicate single liquid-cathode feed water electrolysis cells to evaluate operational performance with increasing levels of a mixture of five bacteria isolated from ISS and Space Shuttle potable water systems. Baseline performance of the single water electrolysis cells was determined for approximately one month with deionized water. Monthly performance was also determined following each inoculation of the feed tank with 100, 1000, 10,000 and 100,000 cells/ml of the mixed suspension of test bacteria. Water samples from the feed tank and recirculating water loops for each cell were periodically analyzed for enumeration and speciation of bacteria and total organic carbon. While initially a concern, this test program has demonstrated that the performance of the electrolysis cell is not adversely impacted by feed water containing the five species of bacteria tested at a concentration measured as high as 1,000,000 colony forming units (CFU)/ml. This paper presents the methodologies used in the conduct of this test program along with the performance test results at each level of bacteria concentration.

Critical level setting of continuous air monitor.

PubMed

Li, Huibin; Jia, Mingyan; Wang, Kailiang

2013-01-01

Algorithms used to compensate the radon and thoron progeny's interference are one of the key technologies for continuous air monitors (CAMs). In this study, a CAM that can automatically change filter was manufactured, and equations used to calculate the transuranic aerosol concentration and the corresponding critical level were derived. The parameters used in calculation were acquired by continuous measurement in a high radon environment. At last, validation of the calculation was tested in a cave where the radon concentration fluctuated frequently, and the results were analysed.

The detection of THC, CBD and CBN in the oral fluid of Sativex® patients using two on-site screening tests and LC-MS/MS.

PubMed

Molnar, Anna; Fu, Shanlin; Lewis, John; Allsop, David J; Copeland, Jan

2014-05-01

Sativex(®) is an oromucosal spray used to treat spasticity in multiple sclerosis sufferers in some European countries, the United Kingdom, Canada and New Zealand. The drug has also recently been registered by the Therapeutic Goods Administration (TGA) in Australia for treatment of multiple sclerosis. Sativex(®) contains high concentrations of Δ(9)-tetrahydrocannabinol (THC) and cannabidiol (CBD), with the former being the subject of random roadside drug tests across Australia to detect cannabis use. This pilot study aims to determine whether or not patients taking Sativex(®) will test positive to THC using these roadside screening tests. Detectable levels of THC, CBD and cannabinol (CBN) in their oral fluid were also confirmed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The study was a double-blind, placebo controlled design. Oral fluid was tested prior to and immediately after dosing with either Sativex(®) or placebo at intervals up to 2h after the dose. Two Sativex(®) doses were studied. The low dose contained 5.4mg THC, the high dose 21.6mg THC. Results indicate that the primary screening test used in Australian roadside drug testing, the DrugWipe(®) II Twin, often gave a false negative response for THC, even with high concentrations present. However, secondary screening test, Cozart(®) DDS (used by police after a DrugWipe test gives a positive result), gave true positive results in all cases where patients were being treated with Sativex(®). Confirmatory testing showed high concentrations of THC and CBD (>5356ng/mL THC and >3826ng/mL CBD) in the oral fluid shortly after dosing and also elevated concentrations of CBN. Levels dropped quickly but remained at detectable concentrations (>67.6ng/mL) two hours after drug administration. The average concentration ratio of THC/CBD across all positive samples was 1.10 (%RSD 19.9) reflecting the composition of the Sativex(®) spray. In conclusion, Sativex(®) users may test positive for THC by roadside drug testing within 2-3h of use. Confirmatory analysis can identify Sativex(®) treatment through use of THC/CBD ratios, however, these ratios would unlikely be sufficient to differentiate non-medicinal cannabis use from Sativex(®) use if both are taken concurrently. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Incidence of anaphylactic reactions after propofol administration in dogs.

PubMed

Onuma, Mamoru; Terada, Misao; Ono, Sadaharu; Murakami, Akiyoshi; Ishida, Tomoko; Sano, Tadashi

2017-08-18

Propofol is an anesthetic agent suspended in an emulsion system that includes egg yolk lecithin and soybean oil, because of which, there is concern about the use of propofol in patients allergic to these substances. We examined the association between propofol administration and incidence of adverse events in dogs with allergy to egg yolk lecithin and soybean oil. On the basis of the findings of an allergen-specific immunoglobulin E (IgE) test, 14 dogs with high levels (high-IgE group) and 7 dogs with low levels (normal-IgE group) of IgE were selected. Following intravenous administration of propofol, the incidence of anaphylactic reactions and plasma histamine concentrations under general anesthesia maintained with isoflurane throughout surgery were compared between the two groups. The frequency of anaphylactic reactions and plasma histamine concentrations were compared by the chi-square test and Student t-test, respectively. The statistical significance for both tests was set at P<0.05. In the high- and normal-IgE groups, the average frequencies of anaphylactic reactions after propofol administration were 21.4 and 14.3%, and the mean plasma histamine concentrations were 167.9 ± 94.5 nM and 65.7 ± 40.3 nM, respectively. Animals of neither groups experienced shock-like symptoms. These results revealed that propofol might be relatively safe, although careful perioperative anesthesia monitoring and standby protocols are required when using propofol in dogs with a history of allergic diseases or high chicken- or soybean-specific IgE levels.

Incidence of anaphylactic reactions after propofol administration in dogs

PubMed Central

ONUMA, Mamoru; TERADA, Misao; ONO, Sadaharu; MURAKAMI, Akiyoshi; ISHIDA, Tomoko; SANO, Tadashi

2017-01-01

Propofol is an anesthetic agent suspended in an emulsion system that includes egg yolk lecithin and soybean oil, because of which, there is concern about the use of propofol in patients allergic to these substances. We examined the association between propofol administration and incidence of adverse events in dogs with allergy to egg yolk lecithin and soybean oil. On the basis of the findings of an allergen-specific immunoglobulin E (IgE) test, 14 dogs with high levels (high-IgE group) and 7 dogs with low levels (normal-IgE group) of IgE were selected. Following intravenous administration of propofol, the incidence of anaphylactic reactions and plasma histamine concentrations under general anesthesia maintained with isoflurane throughout surgery were compared between the two groups. The frequency of anaphylactic reactions and plasma histamine concentrations were compared by the chi-square test and Student t-test, respectively. The statistical significance for both tests was set at P<0.05. In the high- and normal-IgE groups, the average frequencies of anaphylactic reactions after propofol administration were 21.4 and 14.3%, and the mean plasma histamine concentrations were 167.9 ± 94.5 nM and 65.7 ± 40.3 nM, respectively. Animals of neither groups experienced shock-like symptoms. These results revealed that propofol might be relatively safe, although careful perioperative anesthesia monitoring and standby protocols are required when using propofol in dogs with a history of allergic diseases or high chicken- or soybean-specific IgE levels. PMID:28717055

Development of rearing and testing protocols for a new freshwater sediment test species: the gastropod Valvata piscinalis.

PubMed

Ducrot, Virginie; Cognat, Claudine; Mons, Raphaël; Mouthon, Jacques; Garric, Jeanne

2006-03-01

This paper aimed at proposing rearing and testing protocols for Valvata piscinalis, a new potential species for sediment toxicity testing. Such tests were developed since this species reliably represents the bio/ecological characteristics of other gastropods. It may thus be representative of their sensitivity to chemicals. V. piscinalis was successfully cultured in our laboratory for six generations. Cultures provided a high productivity for a low working time and low costs. The tests conditions we proposed seemed to be relevant for the development of reliable tests with this species. Indeed, hatching probability of egg-capsules, as well as embryo, newborn and juvenile survival rates, were close to 100%. Moreover, growth rates and fecundity were significantly higher than in field and in other laboratory studies. Partial life-cycle tests on clean sediments were achieved for various feeding levels to determine survival, growth and reproduction patterns, ad libitum feeding level and life cycle parameters values. Ad libitum feeding levels for newborn, juveniles and adults were 0.1, 0.4 and 0.8 mg Tetramin/individual/working day. Growth tests with zinc-spiked sediments provided a no-effect concentration and a lowest effect concentration of respectively 200 and 624 mg zinc/kg dry sediment. Other growth tests on spiked sediments we ran at our laboratory with second, third and fourth instars larvae of Chironomus riparius pointed out that V. piscinalis was more sensible to zinc than the chironomid, which is a routine test species in ecotoxicology. According to these results, V. piscinalis is a promising candidate species for sediment toxicity testing.

Cognitive disparities, lead plumbing, and water chemistry: prior exposure to water-borne lead and intelligence test scores among World War Two U.S. Army enlistees.

PubMed

Ferrie, Joseph P; Rolf, Karen; Troesken, Werner

2012-01-01

Higher prior exposure to water-borne lead among male World War Two U.S. Army enlistees was associated with lower intelligence test scores. Exposure was proxied by urban residence and the water pH levels of the cities where enlistees lived in 1930. Army General Classification Test scores were six points lower (nearly 1/3 standard deviation) where pH was 6 (so the water lead concentration for a given amount of lead piping was higher) than where pH was 7 (so the concentration was lower). This difference rose with time exposed. At this time, the dangers of exposure to lead in water were not widely known and lead was ubiquitous in water systems, so these results are not likely the effect of individuals selecting into locations with different levels of exposure. Copyright © 2011 Elsevier B.V. All rights reserved.

Swimming performance of young lake trout after chronic exposure to PCBs and DDE

USGS Publications Warehouse

Rottiers, Donald V.; Bergstedt, Roger A.

1981-01-01

Swimming performance was measured in fry of lake trout (Salvelinus namaycush) exposed to PCB's, DDE, and a combination of these two contaminants in both food and water at concentrations equal to, and 5 and 25 times higher than, levels found in Lake Michigan water and plankton. Fry were tested after about 50, 110, and 165 days of exposure. We measured swimming performance by forcing the fry to swim through a continuous series of incrementally increased velocities until the fish were exhausted. Although we observed significant differences in swimming performance between a few test groups, we detected no relation between swimming performance of the fry and exposure to PCB's or DDE, or both, at the concentrations tested. Inasmuch as swimming performance apparently was not affected by the levels of contamination by PCB's and DDE in Lake Michigan, impairment of swimming by these contaminants cannot account for the failure of lake trout reproduction in Lake Michigan.

Variation of Metallothionein I and II Gene Expression in the Bank Vole (Clethrionomys glareolus) Under Environmental Zinc and Cadmium Exposure.

PubMed

Mikowska, Magdalena; Dziublińska, Barbara; Świergosz-Kowalewska, Renata

2018-07-01

The main idea of the study was to assess how environmental metal pollution activates defence responses at transcription levels in the tissues of bank voles (Clethrionomys glareolus). For this purpose, the metallothioneine (MT) genes expression (a well known biomarker of exposure and response to various metals) was measured. The real-time PCR method was used for relative quantification of metallothionein I and metallothionein II expressions in the livers, kidneys and testes of bank voles from six populations exposed to different contaminants, mainly zinc, cadmium and iron. The assessment of Zn, Cu and Fe concentrations in the tissues allowed to study the MTs gene expression responses to these metals. ANOVA analysis showed differences between populations in terms of metal concentration in tissues, livers and kidneys. Student T test showed significant differences in metal concentration between unpolluted and polluted sites only for the liver tissue: significantly lower Zn levels and significantly higher Fe levels in the unpolluted sites. Kruskal-Wallis test performed on C T data shows differences in the gene expressions between populations for both MT genes for liver and testes. In the liver metallothionein I gene expression was upregulated in populations considered as more polluted (up to 7.5 higher expression in Miasteczko Śląskie comparing to Mikołajki). Expression of metallothionein II revealed a similar pattern. In kidneys, differences in expression of both MT genes were not that evident. In testes, MT upregulation in polluted sites was noted for metallothionein II. For metallothionein however, we found downregulation in populations from more contaminated sites. The expressions of both MTs were positively influenced by cadmium in kidney (concentration data from the previous study) and zinc and copper in liver, while cadmium had effects only on the liver MT II gene expression. Positive relationship was obtained for lead and metallothionein II expression in the liver.

Study of metals concentration levels in Patella piperata throughout the Canary Islands, Spain.

PubMed

Bergasa, Oscar; Ramírez, Rubén; Collado, Cayetano; Hernández-Brito, J Joaquín; Gelado-Caballero, María Dolores; Rodríguez-Somozas, María; Haroun, Ricardo J

2007-04-01

In order to assess the extent of metal contamination at rocky shores of the Canarian Archipelago, metal concentrations have been measured in Patella piperata (Gould, 1846), using the standard atomic absorption spectrophotometer technique. Ranges of elements concentrations measured (in microg g(-1)) found in the biota were: Cd (0.36 +/- 0.26 microg g(-1) dry wt.), Cu (2.05 +/- 0.91 dry wt.), Pb (1.57 +/- 1.14 microg g(-1)dry wt.) and Zn (10.37 +/- 4.60 microg g(-1) dry wt.). Variation in metal concentrations in Patella, was tested by using non-parametric statistical methods. Cd content had a maximum in the Archipelago Chinijo, northward of Lanzarote Island. The metal concentrations recorded at the clean stations may be considered carefully if they are used like background levels.

Instrumentation for accelerated life tests of concentrator solar cells.

PubMed

Núñez, N; Vázquez, M; González, J R; Jiménez, F J; Bautista, J

2011-02-01

Concentrator photovoltaic is an emergent technology that may be a good economical and efficient alternative for the generation of electricity at a competitive cost. However, the reliability of these new solar cells and systems is still an open issue due to the high-irradiation level they are subjected to as well as the electrical and thermal stresses that they are expected to endure. To evaluate the reliability in a short period of time, accelerated aging tests are essential. Thermal aging tests for concentrator photovoltaic solar cells and systems under illumination are not available because no technical solution to the problem of reaching the working concentration inside a climatic chamber has been available. This work presents an automatic instrumentation system that overcomes the aforementioned limitation. Working conditions have been simulated by forward biasing the solar cells to the current they would handle at the working concentration (in this case, 700 and 1050 times the irradiance at one standard sun). The instrumentation system has been deployed for more than 10 000 h in a thermal aging test for III-V concentrator solar cells, in which the generated power evolution at different temperatures has been monitored. As a result of this test, the acceleration factor has been calculated, thus allowing for the degradation evolution at any temperature in addition to normal working conditions to be obtained.

Degradation of soil cyanide by single and mixed cultures of Pseudomonas stutzeri and Bacillus subtilis.

PubMed

Nwokoro, Ogbonnaya; Dibua, Marie Esther Uju

2014-03-01

The aim of this investigation was to study whether certain bacteria could be used for cyanide degradation in soil. The bacteria Pseudomonas stutzeri and Bacillus subtilis were selected based on their good growth in a minimal medium containing 0.8 mg mL-1 potassium cyanide (KCN). In this study we tested their ability to reduce cyanide levels in a medium containing 1.5 mg mL-1 of KCN. Although both microorganisms reduced cyanide levels, Pseudomonas stutzeri was the more effective test organism. Later on, the selected cultures were grown, diluted and their various cell concentrations were used individually and in combination to test their ability of cyanide degradation in soil samples collected around a cassava processing mill. Bacillus subtilis caused degradation of soil cyanide from 0.218 mg g-1 soil immediately with an inoculum concentration of 0.1 (OD600nm) to 0.072 mg g-1 soil after 10 days with an inoculum concentration of 0.6 (OD600nm) implying a 66.9 % reduction. Pseudomonas stutzeri cell concentration of 0.1 (OD600nm) decreased soil cyanide from 0.218 mg g-1 soil initially to 0.061 mg g-1 soil after 10 days with an inoculum concentration of 0.6 (OD600nm) (72 % reduction). The mixed culture of the two bacteria produced the best degradation of soil cyanide from 0.218 mg g-1 soil sample with a combined inoculum concentration of 0.1 (OD600nm) initially to 0.025 mg g-1 soil with a combined inoculum concentration of 0.6 (OD600nm) after 10 days incubation resulting in an 88.5 % degradation of soil cyanide. The analysed bacteria displayed high cyanide degradation potential and may be useful for efficient decontamination of cyanide contaminated sites.

Effects of processed oil shale on the element content of Atriplex cancescens

USGS Publications Warehouse

Anderson, B.M.

1982-01-01

Samples of four-wing saltbush were collected from the Colorado State University Intensive Oil Shale Revegetation Study Site test plots in the Piceance basin, Colorado. The test plots were constructed to evaluate the effects of processed oil shale geochemistry on plant growth using various thicknesses of soil cover over the processed shale and/or over a gravel barrier between the shale and soil. Generally, the thicker the soil cover, the less the influence of the shale geochemistry on the element concentrations in the plants. Concentrations of 20 elements were larger in the ash of four-wing saltbush growing on the plot with the gravel barrier (between the soil and processed shale) when compared to the sample from the control plot. A greater water content in the soil in this plot has been reported, and the interaction between the increased, percolating water and shale may have increased the availability of these elements for plant uptake. Concentrations of boron, copper, fluorine, lithium, molybdenum, selenium, silicon, and zinc were larger in the samples grown over processed shale, compared to those from the control plot, and concentrations for barium, calcium, lanthanum, niobium, phosphorus, and strontium were smaller. Concentrations for arsenic, boron, fluorine, molybdenum, and selenium-- considered to be potential toxic contaminants--were similar to results reported in the literature for vegetation from the test plots. The copper-to-molybdenum ratios in three of the four samples of four-wing saltbush growing over the processed shale were below the ratio of 2:1, which is judged detrimental to ruminants, particularly cattle. Boron concentrations averaged 140 ppm, well above the phytotoxicity level for most plant species. Arsenic, fluorine, and selenium concentrations were below toxic levels, and thus should not present any problem for revegetation or forage use at this time.

The effects of serum leptin levels on thrombocyte aggregation in peritoneal dialysis patients.

PubMed

Bakirdogen, Serkan; Eren, Necmi; Bek, Sibel Gokcay; Mehtap, Ozgur; Cekmen, Mustafa Baki

2016-01-01

Serum leptin levels of chronic kidney disease patients have been detected higher than normal population. The aim of this study was to investigate the effects of serum leptin levels on thrombocyte aggregation in peritoneal dialysis patients. Fourty three peritoneal dialysis patients were included in the study. Thrombocyte aggregation was calculated from the whole blood subsequently the effects of different concentrations of human recombinant leptin on thrombocyte aggregations were investigated. Four test cells were used for this process. While leptin was not added into the first test cell, increasing amounts of leptin was added into the second, third and fourth test cells to attain the concentrations of 25, 50 and 100 ng/ml respectively. Thrombocyte aggregation was inhibited by recombinant leptin in peritoneal dialysis patients. Thrombocyte aggregation mean values were found statistically significantly higher in first test cell when compared to leptin groups in peritoneal dialysis patients. For leptin groups we could not find any statistically significant differences for thrombocyte aggregation mean values between any of the groups. Further studies with larger number of peritoneal dialysis patients are required to prove the action of leptin on thrombocyte aggregation.

The effects of serum leptin levels on thrombocyte aggregation in peritoneal dialysis patients

PubMed Central

Bakirdogen, Serkan; Eren, Necmi; Bek, Sibel Gokcay; Mehtap, Ozgur; Cekmen, Mustafa Baki

2016-01-01

Objective: Serum leptin levels of chronic kidney disease patients have been detected higher than normal population. The aim of this study was to investigate the effects of serum leptin levels on thrombocyte aggregation in peritoneal dialysis patients. Methods: Fourty three peritoneal dialysis patients were included in the study. Thrombocyte aggregation was calculated from the whole blood subsequently the effects of different concentrations of human recombinant leptin on thrombocyte aggregations were investigated. Four test cells were used for this process. While leptin was not added into the first test cell, increasing amounts of leptin was added into the second, third and fourth test cells to attain the concentrations of 25, 50 and 100 ng/ml respectively. Results: Thrombocyte aggregation was inhibited by recombinant leptin in peritoneal dialysis patients. Thrombocyte aggregation mean values were found statistically significantly higher in first test cell when compared to leptin groups in peritoneal dialysis patients. For leptin groups we could not find any statistically significant differences for thrombocyte aggregation mean values between any of the groups. Conclusion: Further studies with larger number of peritoneal dialysis patients are required to prove the action of leptin on thrombocyte aggregation. PMID:28083046

Microbial destruction by low concentrations of hypochlorite and iodophor germicides in alkaline and acidified water.

PubMed

Hays, H; Elliker, P R; Sandine, W E

1967-05-01

Hypochlorite and iodophor germicides were evaluated for their ability to destroy a variety of organisms at levels approximating those used for final sanitizing rinse for dairy and food equipment and beverage bottles (3 to 50 ppm). Test organisms included Escherichia coli, Streptococcus lactis, Lactobacillus plantarum, Pediococcus cerevisiae, and Saccharomyces cerevisiae. The hypochlorites and iodophors demonstrated approximate rates of destruction at equivalent concentrations for the bacterial species tested, except where the hypochlorite contained excess alkalinity. The hypochlorite responded more readily to a downward shift to a pH of 5.0 than did the iodophor. Excess alkalinity of the hypochlorite significantly affected its bactericidal activity. The iodophor exhibited a consistently greater rate of destruction of yeast cells than the hypochlorite. Successive treatment with low levels of iodophor (6 ppm) followed by a hypochlorite (12 to 25 ppm) resulted in a high level of destruction of all test organisms. Possibilities for employing these measures in a sanitizing rinse of bottles for maximal destruction of organisms were discussed. Among the test organisms, S. lactis showed a comparatively high resistance and was a useful organism for comparing the halogen preparations.

Automated screening method for determining optimum preservative systems for personal and home care products.

PubMed

Lenczewski, M E; Kananen, L L

1998-01-01

A procedure was designed to determine the minimum preservative level (MPL) for personal and home care products. A highly preserved sample and an unpreserved sample were combined at different concentrations within a 96-well microtiter plate by using an autodilutor. A unique tip design made it possible to accurately deliver viscous test materials that cannot be dispensed using vacuum- or fluid-filled systems. After inoculation, the sample was evaluated at a specified time interval for the presence of surviving bacteria, yeast, and mold. The lowest concentration of preservative with no microbial growth is the recommended level of preservative for the product. Because sample turbidity may interfere with determination of the endpoint, a colorimetric endpoint was used to indicate growth of microorganisms and to differentiate product from growth. The predicted levels were tested with a modified Cosmetic, Toiletry, and Fragrance Association method. The method successfully predicted effective preservative levels in many personal and home care products with a broad range of viscosities.

Serum concentrations of polychlorinated dibenzo-p-dioxins among ceramicists.

PubMed

Demond, Avery; Jiang, Xiaohui; Broadwater, Kendra; Meeker, John; Luksemburg, William; Maier, Martha; Garabrant, David; Franzblau, Alfred

2015-01-01

Polychlorinated dibenzo-p-dioxins (PCDDs) occur naturally in ball clay at elevated concentrations. Thus, persons who habitually work with clay may be at risk for exposure to PCDDs. An earlier case report provided some evidence of elevated PCDD levels in serum for long-term hobby ceramicists; however, no previous study has measured serum dioxin concentrations among ceramicists. This study measured PCDD serum levels for 27 individuals involved in ceramics making. The average residual, defined as the average of the [log measured serum lipid concentration – log background serum lipid concentration], was calculated and then tested to determine whether it was significantly different from zero. The p-values for the average residuals indicated that the serum lipid concentrations for several PCDD congeners were elevated relative to background. The number of significant residuals increased dramatically if the background concentrations were adjusted to account for the fact that they were not contemporaneous with the measurements for the ceramicists. The ratio of the 1,2,3,6,7,8-HxCDD concentration to the 1,2,3,7,8,9-HxCDD concentration was greater than 1.0, unlike in ball clay, suggesting that although long-term working with ball clay elevates the PCDD levels in serum somewhat, it is not the predominant source of the PCDD body burden for ceramicists.

Low-Dose Aronia melanocarpa Concentrate Attenuates Paraquat-Induced Neurotoxicity

PubMed Central

Case, A. J.; Agraz, D.; Ahmad, I. M.; Zimmerman, M. C.

2016-01-01

Herbicides containing paraquat may contribute to the pathogenesis of neurodegenerative disorders such as Parkinson's disease. Paraquat induces reactive oxygen species-mediated apoptosis in neurons, which is a primary mechanism behind its toxicity. We sought to test the effectiveness of a commercially available polyphenol-rich Aronia melanocarpa (aronia berry) concentrate in the amelioration of paraquat-induced neurotoxicity. Considering the abundance of antioxidants in aronia berries, we hypothesized that aronia berry concentrate attenuates the paraquat-induced increase in reactive oxygen species and protects against paraquat-mediated neuronal cell death. Using a neuronal cell culture model, we observed that low doses of aronia berry concentrate protected against paraquat-mediated neurotoxicity. Additionally, low doses of the concentrate attenuated the paraquat-induced increase in superoxide, hydrogen peroxide, and oxidized glutathione levels. Interestingly, high doses of aronia berry concentrate increased neuronal superoxide levels independent of paraquat, while at the same time decreasing hydrogen peroxide. Moreover, high-dose aronia berry concentrate potentiated paraquat-induced superoxide production and neuronal cell death. In summary, aronia berry concentrate at low doses restores the homeostatic redox environment of neurons treated with paraquat, while high doses exacerbate the imbalance leading to further cell death. Our findings support that moderate levels of aronia berry concentrate may prevent reactive oxygen species-mediated neurotoxicity. PMID:26770655

Low-Dose Aronia melanocarpa Concentrate Attenuates Paraquat-Induced Neurotoxicity.

PubMed

Case, A J; Agraz, D; Ahmad, I M; Zimmerman, M C

2016-01-01

Herbicides containing paraquat may contribute to the pathogenesis of neurodegenerative disorders such as Parkinson's disease. Paraquat induces reactive oxygen species-mediated apoptosis in neurons, which is a primary mechanism behind its toxicity. We sought to test the effectiveness of a commercially available polyphenol-rich Aronia melanocarpa (aronia berry) concentrate in the amelioration of paraquat-induced neurotoxicity. Considering the abundance of antioxidants in aronia berries, we hypothesized that aronia berry concentrate attenuates the paraquat-induced increase in reactive oxygen species and protects against paraquat-mediated neuronal cell death. Using a neuronal cell culture model, we observed that low doses of aronia berry concentrate protected against paraquat-mediated neurotoxicity. Additionally, low doses of the concentrate attenuated the paraquat-induced increase in superoxide, hydrogen peroxide, and oxidized glutathione levels. Interestingly, high doses of aronia berry concentrate increased neuronal superoxide levels independent of paraquat, while at the same time decreasing hydrogen peroxide. Moreover, high-dose aronia berry concentrate potentiated paraquat-induced superoxide production and neuronal cell death. In summary, aronia berry concentrate at low doses restores the homeostatic redox environment of neurons treated with paraquat, while high doses exacerbate the imbalance leading to further cell death. Our findings support that moderate levels of aronia berry concentrate may prevent reactive oxygen species-mediated neurotoxicity.

Hyaluronic acid coated poly-epsilon-caprolactone nanospheres deliver high concentrations of cyclosporine A into the cornea.

PubMed

Yenice, Irem; Mocan, Mehmet C; Palaska, Erhan; Bochot, Amélie; Bilensoy, Erem; Vural, Imran; Irkeç, Murat; Hincal, A Atilla

2008-09-01

The objective of this study was to determine cyclosporine A (Cy A) levels in ocular tissues and fluids after topical administration of poly-epsilon-caprolactone (PCL)/benzalkonium chloride (BKC) nanospheres and hyaluronic acid (HA) coated PCL/BKC nanospheres onto healthy rabbit corneas. Nanospheres were prepared by nanoprecipitation and purified by gradient-rate centrifugation. Cy A (0.1%) in either castor oil solution (group 1), PCL/BKC nanosphere formulation (group 2) or HA coated PCL/BKC nanosphere formulation (group 3) was instilled onto rabbit corneas. Tear samples were adsorbed onto Schirmer tear strips. Cy A concentrations of fluid (blood, aqueous humor, tear) and specimen extracts (cornea, conjunctiva, iris/ciliary body) were determined by high performance liquid chromatography-mass spectrometry (LC-MS). The mean corneal Cy A concentration obtained at 0.5, 1, 2, 4, 8 and 24h following instillation of the formulations ranged between 0.12 and 1.2 ng/mg tissue for group 1, 5.9-15.5 ng/mg tissue for group 2 and 11.4-23.0 ng/mg for group 3 (one-way analysis of variance (ANOVA) and pairwise tests (SNK (Student-Newman-Keuls) and Tukey); p<0.05). Conjunctival Cy A levels of group 2 and 3 were not significantly different at any of the time points tested. However, there was a significant difference between Cy A concentration of castor oil formulation and that of PCL/BKC nanosphere formulation at 1 and 8h (p<0.05). The mean iris/ciliary body concentrations obtained with the three formulations were not significantly different at any time point with the exception of group 2 levels being higher than those of groups 1 and 3 at 1h (p<0.05). The lowest ocular tear Cy A concentrations (16-114 ng/ml) were found following the instillation of HA coated PCL/BKC nanoparticles (group 3) during the time period tested. Cy A loaded PCL/BKC and HA coated PCL/BKC nanospheres are able to achieve high levels of Cy A in the cornea that is 10-15-fold higher than that is achieved with Cy A solution in castor oil. Nanosphere formulation and HA may play an important role in delivering high levels of cyclosporine A into the cornea.

Acute effects of the electromagnetic waves emitted by mobile phones on attention in emergency physicians.

PubMed

Altuntas, Gurkan; Sadoglu, Davut; Ardic, Senol; Yilmaz, Hakan; Imamoglu, Melih; Turedi, Suleyman

2018-03-01

The purpose of this study was to investigate the acute effects of the electromagnetic waves (EMW) emitted by mobile phones on attention in emergency physicians. This single-center, prospective, randomized, double-blinded clinical study was performed among emergency physicians in a tertiary hospital. Thirty emergency physicians were enrolled in the study. Initial d2 test was applied in the evaluation of attention and concentration of all the physicians, who were randomly assigned into one of two groups. The control group members hold mobile phones in 'off' mode to their left ears for 15min. The members of the intervention group hold mobile phones in 'on' mode to their left ears for 15min, thus exposing them to 900-1800MHz EMW. The d2 test was re-applied to both groups after this procedure. Differences in attention and concentration levels between the groups were compared. Difference between initial and final d2 test in total performance (TN-E, p=0.319), in total number of figures marked (TN, p=0.177), in test performance percentile (PR, p=0.619) and in attention fluctuation (FR, p=0.083) were similar between the groups. However, difference in the number of figures missed (E1 selective attention, p=0.025), difference between numbers of incorrectly marked figures (E2, p=0,018) and difference in focus levels (E, p=0.016) were significantly in favor of the intervention group. According to our study findings, the EMW emitted by mobile phones has no deleterious effect on the attention and concentration levels of emergency physicians, and even has a positive impact on selective attention levels. Copyright © 2017 Elsevier Inc. All rights reserved.

40 CFR 799.9539 - TSCA mammalian erythrocyte micronucleus test.

Code of Federal Regulations, 2010 CFR

2010-07-01

... peripheral blood). (iv) Limit test. If a test at one dose level of at least 2,000 mg/kg body weight using a... dose is 2,000 mg/kg/body weight/day for treatment up to 14 days, and 1,000 mg/kg/body weight/day for... water test substance concentration parts per million (ppm) to the actual dose (mg/kg body weight/day...

Elevation of serum CA 125 and D-dimer levels associated with rupture of ovarian endometrioma.

PubMed

Uharcek, P; Mlyncek, M; Ravinger, J

2007-01-01

Patients with endometriosis rarely have a serum CA 125 concentration >100 IU/mL. A raised plasma level of D-dimer indicates active fibrinolysis, either secondary to clot formation or primarily activated. This condition is seldom diagnosed in patients with endometriosis. A 53-year-old woman was referred to our institution for acute abdominal pain. Laparoscopic surgery revealed a large ovarian cyst with rupture on the left side. Preoperative laboratory tests detected high serum CA 125 and D-dimer levels. Adnexectomy was performed, resulting in a sharp decrease in serum CA 125 and D-dimer concentration. We describe the clinical course of the patient. Rupture of a large ovarian endometrioma can lead to a high serum concentration of CA 125, a condition which, in addition to the detected pelvic mass, may mimic a malignant process. The increased D-dimer plasma level indicated that a ruptured endometriotic cyst can induce coagulation reactions.

Early cannabinoid exposure influences neuroendocrine and reproductive functions in male mice: I. Prenatal exposure.

PubMed

Dalterio, S; Steger, R; Mayfield, D; Bartke, A

1984-01-01

Maternal exposure to delta 9-tetrahydrocannabinol (THC), the major psychoactive constituent in marihuana, or to the non-psychoactive cannabinol (CBN) or cannabidiol (CBD) alters endocrine functions and concentrations of brain biogenic amines in their male offspring. Prenatal CBN exposure on day 18 of gestation resulted in decreased plasma FSH levels, testicular testosterone (T) concentrations, and seminal vesicles weights, but increased plasma levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) post-castration in adulthood. Prenatal exposure to THC significantly enhanced the responsiveness of the testes to intratesticular LH injection in vivo and tended to increase human chorionic gonadotropin (hCG)-stimulated T production by decapsulated testes in vitro. In the CBN-exposed mice, hCG-stimulated T production was enhanced, while CBD exposure had no effect. Prenatal THC exposure altered the negative feedback effects of exogenous gonadal steroids in castrated adults, with lower plasma T and FSH levels after 20 micrograms T than in castrated controls. In contrast, CBD-exposed mice had higher levels of LH in plasma post-castration. In CBN-exposed adults, two weeks post-castration the concentration of norepinephrine (NE) and dopamine (DA) in hypothalamus and remaining brain were reduced, while levels of serotonin (5-HT) and its metabolite, 5-HIAA, were elevated compared to that in castrated OIL-controls. Prenatal CBD-exposure also reduced NE and elevated 5-HT and 5-HIAA, but did not affect DA levels post-castration. Concentrations of brain biogenic amines were not influenced by prenatal THC exposure in the present study. A single prenatal exposure to psychoactive or non-psychoactive components of marihuana results in long term alterations in the function of the hypothalamo-pituitary-gonadal axis. Changes in the concentrations of brain biogenic amines may be related to these effects of prenatal cannabinoids on endocrine function in adult male mice.

Effects of cadmium ingestion and food restriction on energy metabolism and tissue metal concentrations in mallard ducks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Di Giulio, R.T.; Scanlon, P.F.

1985-08-01

The single and combined effects of cadmium ingestion and food restriction were examined in a 42-day experiment with male, juvenile mallard ducks. A 2 x 3 factorial design was employed consisting of two levels of food supply (ad libitum and 55% of ad libitum intake) and three levels of cadmium in the food (0, 5 or 50 ..mu..g Cd/g food). Cadmium ingestion alone had no effect on body or tissue weights, liver glycogen, plasma concentrations of glucose, urea, uric acid, nonesterified fatty acids (NEFA), triiodothyronine (T/sub 3/), thyroxine (T/sub 4/), or plasma or adrenal concentrations of corticosterone. The food restrictionmore » resulted in reduced body weights and reduced weights of livers, kidneys, and testes, increased adrenal weights, reduced liver glycogen, increased plasma NEFA concentrations, reduced plasma T/sub 3/ and T/sub 4/ concentrations, and increased adrenal corticosterone concentrations. In combination with the food restrictions, cadmium ingestion further reduced plasma T/sub 3/ concentrations and a similar trend was noted for T/sub 4/. Additionally, the highest plasma NEFA concentrations and highest plasma and adrenal concentrations of corticosterone were observed in food-restricted ducks receiving the highest level of dietary cadmium. These results suggest that ability of cadmium ingestion to enhanced food restriction-induced alterations in energy metabolism at levels of dietary cadmium that are by themselves without apparent effect. Also, cadmium ingestion resulted in increased kidney concentrations of copper and zinc: this effect on kidney zinc concentrations was increased in food-restricted ducks.« less

A Novel Hypoxia Challenge Test Demonstrates Cardiovascular and Pulmonary Susceptibility to Acrolein Gas in Hypertensive Rats.

EPA Science Inventory

High levels of air pollution increase the risk of cardiovascular morbidity and mortality, especially in susceptible populations including those with hypertension. Stress tests are useful for manifesting latent effects of exposure, particularly at low concentrations, often when no...

Suitability of shredded tyres as a substitute for a landfill leachate collection medium.

PubMed

Park, Jae K; Edil, Tuncer B; Kim, Jae Y; Huh, Mock; Lee, Sung Ho; Lee, Jung Jun

2003-06-01

A series of tests were conducted to investigate the fate of heavy metals and gasoline components in a simulated landfill, consisting of a 30 cm thick clay liner and a leachate collection layer containing tyres as well as in two test cells installed in a landfill. Arsenic, selenium, mercury, barium, and lead concentrations were lower while zinc concentration was higher in the tank containing tyre-chips than the tank without tyre-chips. When samples were filtered, however, concentrations of zinc as well as other inorganics were lower in the tank containing tyre-chips, indicating that metals in the leachate exposed to tyre-chips travel more slowly in a subsurface environment due to filtering effect. In a test cell study, arsenic, cobalt, lead and nickel concentrations were lower in the cell containing tyre-chips than in the cell without tyre-chips, except iron and zinc. Both tests indicate that some inorganic contaminants are sorbed to tyre-chips. Gasoline components were also significantly sorbed by tyre-chips in field cell tests. Although tyre-chips are known to leach organic and inorganic contaminants, concentrations in field conditions will be lower than the reported experimental results since the tests were performed under worst-case scenarios. If tyre-chips are used in areas where contamination levels are high, then they can be used as a sorbent for environmental clean-up.

Using nonesterified fatty acids and β-hydroxybutyrate concentrations during the transition period for herd-level monitoring of increased risk of disease and decreased reproductive and milking performance.

PubMed

Ospina, Paula A; McArt, Jessica A; Overton, Thomas R; Stokol, Tracy; Nydam, Daryl V

2013-07-01

Dairy cows visit a state of negative energy balance (NEB) as they transition from late gestation to early lactation. At the individual level, there are several metabolic adaptations to manage NEB, including mobilization of nonesterified fatty acids (NEFA) from body fat reserves and glucose sparing for lactogenesis. Based on current pen-level feeding and management practices, strategies to minimize excessive NEB in both the individual and herd should focus on herd-level testing and management. This article reviews strategies for testing and monitoring of excessive NEB at the herd level through individual testing of 2 energy markers: NEFA and β-hydroxybutyrate. Copyright © 2013 Elsevier Inc. All rights reserved.

F100 Engine Emissions Tested in NASA Lewis' Propulsion Systems Laboratory

NASA Technical Reports Server (NTRS)

Wey, Chowen C.

1998-01-01

Recent advances in atmospheric sciences have shown that the chemical composition of the entire atmosphere of the planet (gases and airborne particles) has been changed due to human activity and that these changes have changed the heat balance of the planet. National Research Council findings indicate that anthropogenic aerosols1 reduce the amount of solar radiation reaching the Earth's surface. Atmospheric global models suggest that sulfate aerosols change the energy balance of the Northern Hemisphere as much as anthropogenic greenhouse gases have. In response to these findings, NASA initiated the Atmospheric Effects of Aviation Project (AEAP) to advance the research needed to define present and future aircraft emissions and their effects on the Earth's atmosphere. Although the importance of aerosols and their precursors is now well recognized, the characterization of current subsonic engines for these emissions is far from complete. Furthermore, since the relationship of engine operating parameters to aerosol emissions is not known, extrapolation to untested and unbuilt engines necessarily remains highly uncertain. Tests in 1997-an engine test at the NASA Lewis Research Center and the corresponding flight measurement test at the NASA Langley Research Center-attempted to address both issues by measuring emissions when fuels containing different levels of sulfur were burned. Measurement systems from four research groups were involved in the Lewis engine test: A Lewis gas analyzer suite to measure the concentration of gaseous species 1. including NO, NOx, CO, CO2, O2, THC, and SO2 as well as the smoke number; 2. A University of Missouri-Rolla Mobile Aerosol Sampling System to measure aerosol and particulate properties including the total concentration, size distribution, volatility, and hydration property; 3. An Air Force Research Laboratory Chemical Ionization Mass Spectrometer to measure the concentration of SO2 and SO3/H2SO4; and 4. An Aerodyne Research Inc. Tunable Diode Laser System to measure the concentrations of SO2, SO3, NO, NO2, CO2, and H2O. By September 1997, an F100 engine operating at several power levels at sea level and up to six simulated altitudes had been tested with commercial jet fuels with three levels of sulfur content and one military jet fuel. The data are being vigorously analyzed. A complete report is anticipated for the 1998 Atmospheric Effects of Aviation Project Annual Conference.

Elements in whole blood of Northwestern Crows (Corvus caurinus) in Alaska: No evidence for an association with beak deformities

USGS Publications Warehouse

Van Hemert, Caroline R.; Handel, Colleen M.

2016-01-01

A recent outbreak of beak deformities among resident birds in Alaska has raised concern about environmental contamination as a possible underlying factor. We measured whole blood concentrations of 30 essential and nonessential elements to determine whether any were associated with beak deformities in Northwestern Crows (Corvus caurinus). We tested for differences between 1) adults with versus those without beak deformities and 2) unaffected adults versus juveniles. Crows with beak deformities had slightly higher levels of barium, molybdenum, and vanadium (all P<0.05), but concentrations were generally low and within the range of values reported from other apparently healthy wild birds. Concentrations of several elements, including selenium, were higher in birds without versus birds with beak deformities (all P<0.05), a difference that may be explained in part by compromised foraging ability associated with the deformities. Adult crows had higher concentrations of cadmium, silicon, and zinc than juveniles (all P<0.05), although differences were relatively small and values were similar to those from other wild birds. Our results suggest that neither selenium nor other tested elements are likely to be causing beak deformities in Alaskan crows. We also provide the first data on elemental concentrations in Northwestern Crows. Levels of selenium far exceeded those typically found in passerine birds and were similar to those in marine-associated waterfowl, suggesting that background levels should be interpreted relative to a species's environment.

Occurrence of brominated diphenyl ethers, dibenzo-p-dioxins and dibenzofurans in foam materials in scrapped car seats from 1985 to 2012.

PubMed

Redin, L; Niinipuu, M; Jansson, S

2017-03-01

The purpose of this study was to evaluate the occurrence of polybrominated diphenyl ethers (PBDEs), dibenzo-p-dioxins (PBDDs) and dibenzofurans (PBDFs) in polyurethane foam (PUF) from car seats of end-of-life vehicles (ELVs) and compare the concentrations of PBDEs with the stipulated regulations in the POP Directive. The method comprised screening by X-ray fluorescence (XRF) and GG-MS analysis. Of 59 tested samples from ELVs, 17 samples showed lines above limit of detection (LOD) levels when screening by XRF. Those samples were selected as replicates and for further analysis by GC-MS. The majority of the studied samples showed low or non-detectable concentrations of PBDEs and PBDD/Fs, but two samples showed concentrations of Σ Te-HpBDEs close to the regulated level for Te-HpBDEs in waste (1000mgkg -1 ); one was slightly higher (1390mgkg -1 ) and the other slightly lower (570mgkg -1 ). It was concluded that brominated pollutants such as Te-HpBDEs occur in low levels in automotive applications in scrapped cars produced in years when brominated flame retardants were used. However, two of the 59 samples tested showed levels close to those stipulated by regulations concerning POPs in waste. Copyright © 2016 Elsevier Ltd. All rights reserved.

Endocrine, immune, and behavioral effects of aldicarb (carbamate), atrazine (triazine) and nitrate (fertilizer) mixtures at groundwater concentrations.

PubMed

Porter, W P; Jaeger, J W; Carlson, I H

1999-01-01

This paper describes the results of 5 years of research on interactive effects of mixtures of aldicarb, atrazine, and nitrate on endocrine, immune, and nervous system function. The concentrations of chemicals used were the same order of magnitude as current maximum contaminant levels (MCLs) for all three compounds. Such levels occur in groundwater across the United States. Dosing was through voluntary consumption of drinking water. We used fractional and full factorial designs with center replicates to determine multifactor effects. We used chronic doses in experiments that varied in duration from 22 to 103 days. We tested for changes in thyroid hormone levels, ability to make antibodies to foreign proteins, and aggression in wild deer mice, Peromyscus maniculatus, and white outbred Swiss Webster mice, Mus musculus, ND4 strain. Endocrine, immune, and behavior changes occurred due to doses of mixtures, but rarely due to single compounds at the same concentrations. Immune assay data suggest the possibility of seasonal effects at low doses. We present a multiple-level model to help interpret the data in the context of human health and biological conservation concerns. We discuss six testing deficiencies of currently registered pesticides, and suggest areas of human health concerns if present trends in pesticide use continue.

Training Status as a Marker of the Relationship between Nitric Oxide, Oxidative Stress, and Blood Pressure in Older Adult Women.

PubMed

Jacomini, André Mourão; de Souza, Hugo Celso Dutra; Dias, Danielle da Silva; Brito, Janaina de Oliveira; Pinheiro, Lucas Cezar; da Silva, Anderson Bernardino; da Silva, Roberta Fernanda; Trapé, Atila Alexandre; De Angelis, Kátia; Tanus-Santos, José Eduardo; do Amaral, Sandra Lia; Zago, Anderson Saranz

2015-01-01

The purpose of this study was to evaluate the influence of functional fitness and oxidative capacity on the nitric oxide concentration associated with hemodynamic control in older adult women. The sample consisted of 134 women (65.73 ± 6.14 years old). All subjects underwent a physical examination to assess body mass index, waist-hip ratio, body fat measurement by dual energy X-ray absorptiometry, and blood pressure (BP). Training status (TS) was evaluated by indirect determination of maximal oxygen uptake by a treadmill test using Balke protocol modified for older adults. Functional fitness was also evaluated through a "Functional Fitness Battery Test" to determine the general fitness functional index (GFFI). All participants were separated according to the functional fitness (TS1, very weak and weak; TS2, regular; TS3, good and very good). Plasma blood samples were used to evaluate prooxidant and antioxidant activity and nitrite and nitrate concentrations. The general results of this study showed that good levels of TS were related to lower levels of lipoperoxidation and protein damage, higher levels of antioxidant, and higher concentration of nitrite and nitrate. This combination may be responsible for the lower levels of BP in subjects with better TS.

Cypermethrin and lambda-cyhalothrin induced alterations in nucleic acids and protein contents in a freshwater fish, Channa punctatus.

PubMed

Kumar, Amit; Sharma, Bechan; Pandey, Ravi Shankar

2008-12-01

In this study, a freshwater fish Channa punctatus was exposed to subacute concentrations of synthetic pyrethroid insecticides (cypermethrin and lambda-cyhalothrin) for 96 h to evaluate their impact on the levels of nucleic acids and protein in its different organs. Significant enhancement in the level of DNA was recorded in all tissues of the fish at high concentration of cypermethrin, whereas RNA and protein contents increased in tissues at all concentrations of cypermethrin tested. In contrast, lambda-cyhalothrin treatment caused an increase in the level of DNA only in liver and brain, whereas increase of RNA and protein varied to different levels in different tissues. Cypermethrin treatment induced RNA/DNA ratio in all fish organs tested, whereas lambda-cyhalothrin caused a sharp decrease in the ratio. Protein/DNA ratios were found to be tissue specific in treatments with both of the insecticides. The results clearly indicated that both of these pyrethroids exerted their effects in a similar manner in fish liver but differed in other tissues. These insecticides acted as potential biomodulators in C. punctatus, though following different routes. The results may be an indicator of aquatic pollution affecting freshwater fauna and flora and thus signaling the need for strict regulation on the indiscriminate input of pyrethroids from agricultural sites.

Investigating Indoor Radon Levels and Influencing Factors in Primary Schools of Zulfi City, Saudi Arabia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Al-Ghamdi, S. S.; Al-Garawi, M. S.; Al-Mosa, Tahani M.

Measurement of indoor Concentrations were performed in Zulfi city of Saudi Arabia, using CR-39 track etch detectors. This investigation focused on the influence of different parameters, namely different locations, school categories, school building types, and room type as well as on the existence of differences in radon concentration at floor levels. We divided the Zulfi city into five regions, keeping in mind their geographical locations between Tuwaiq Mountains and Al-Thuwayrat sands. The measured average radon concentrations for regions 1-5 respectively are: 87.0{+-}14.2 Bq/m{sup 3}, 83.4{+-}6.0 Bq/m{sup 3}, 61.6{+-}6.4 Bq/m{sup 3}, 63.7{+-}5.4 Bq/m{sup 3} and 87.5{+-}6.Bq/m{sup 3} and the minimum concentrationsmore » are 28.0 Bq/m{sup 3}, 5.5 Bq/m{sup 3}, 1.1 Bq/m{sup 3}, 1.0 Bq/m{sup 3} and 24 Bq/m{sup 3} respectively. These results are still within normal limits and below the action level of 148 Bqm{sup -3} set by the U.S. Environmental Protection Agency (EPA). A test of significance using Minitab program was applied to investigate if radon levels in regions are significantly different from each other. We tried all combinations, and found the following results. The ''within regions''(different location) test yielded, region 2 is not significant versus region ''1''(p = 0.783) and versus region ''5''(P = 0.646), whereas it is significant versus region ''3''(P = 0.0160) and also versus region ''4''(p = 0.018). We investigated government and rented school's building also and none was found significantly different (p = 0.052). Floors of the same building were tested in order to examine the radon concentration as a function of storey level. No significant difference was observed at floor levels (p = 0.009). When girl's schools versus Boys and kindergartens schools were tested they were found significantly different. It is believed that this significant difference is due to geographical nature of the area, since most of the girl's schools were selected from regions 2 and 3, these regions are relatively close to the Tuwaiq mountains whereas other regions are near to the Al-Thuwayrat sands.« less

Evaluation of genotoxicity in workers exposed to low levels of formaldehyde in a furniture manufacturing facility.

PubMed

Peteffi, Giovana Piva; da Silva, Luciano Basso; Antunes, Marina Venzon; Wilhelm, Camila; Valandro, Eduarda Trevizani; Glaeser, Jéssica; Kaefer, Djeine; Linden, Rafael

2016-10-01

Formaldehyde (FA) is a chemical widely used in the furniture industry and has been classified as a potential human carcinogen. The purpose of this study was to evaluate the occupational exposure of workers to FA at a furniture manufacturing facility and the relationship between environmental concentrations of FA, formic acid concentration in urine, and DNA damage. The sample consisted of 46 workers exposed to FA and a control group of 45 individuals with no history of occupational exposure. Environmental concentrations of FA were determined by high-performance liquid chromatography. Urinary formic acid concentrations were determined by gas chromatography with flame ionization detector. DNA damage was evaluated by the micronucleus (MN) test performed in exfoliated buccal cells and comet assay with venous blood. The 8-h time-weighted average of FA environmental concentration ranged from 0.03 ppm to 0.09 ppm at the plant, and the control group was exposed to a mean concentration of 0.012 ppm. Workers exposed to higher environmental FA concentrations had urinary formic acid concentrations significantly different from those of controls (31.85 mg L(-1) vs. 19.35 mg L(-), p ≤ 0.01 Mann-Whitney test). Significant differences were found between control and exposed groups for the following parameters: damage frequency and damage index in the comet assay, frequency of binucleated cells in the MN test, and formic acid concentration in urine. The frequency of micronuclei, nuclear buds, and karyorrhexis did not differ between groups. There was a positive correlation between environmental concentrations of FA and damage frequency (Spearman's rank correlation coefficient [r s] = 0.24), damage index (r s = 0.21), binucleated cells (r s = 0.34), and urinary formic acid concentration (r s = 0.63). The results indicate that, although workers in the furniture manufacturing facility were exposed to low environmental levels of FA, this agent contributes to the observed increase in cytogenetic damage. In addition, urinary formic acid concentrations correlated strongly with occupational exposure to FA. © The Author(s) 2015.

Groundwater level and nitrate concentration trends on Mountain Home Air Force Base, southwestern Idaho

USGS Publications Warehouse

Williams, Marshall L.

2014-01-01

Mountain Home Air Force Base in southwestern Idaho draws most of its drinking water from the regional aquifer. The base is located within the State of Idaho's Mountain Home Groundwater Management Area and is adjacent to the State's Cinder Cone Butte Critical Groundwater Area. Both areas were established by the Idaho Department of Water Resources in the early 1980s because of declining water levels in the regional aquifer. The base also is listed by the Idaho Department of Environmental Quality as a nitrate priority area. The U.S. Geological Survey, in cooperation with the U.S. Air Force, began monitoring wells on the base in 1985, and currently monitors 25 wells for water levels and 17 wells for water quality, primarily nutrients. This report provides a summary of water-level and nitrate concentration data collected primarily between 2001 and 2013 and examines trends in those data. A Regional Kendall Test was run to combine results from all wells to determine an overall regional trend in water level. Groundwater levels declined at an average rate of about 1.08 feet per year. Nitrate concentration trends show that 3 wells (18 percent) are increasing in nitrate concentration trend, 3 wells (18 percent) show a decreasing nitrate concentration trend, and 11 wells (64 percent) show no nitrate concentration trend. Six wells (35 percent) currently exceed the U.S. Environmental Protection Agency's maximum contaminant limit of 10 milligrams per liter for nitrate (nitrite plus nitrate, measured as nitrogen).

Maternal Vitamin D Levels and the Autism Phenotype among Offspring

ERIC Educational Resources Information Center

Whitehouse, Andrew J. O.; Holt, Barbara J.; Serralha, Michael; Holt, Patrick G.; Hart, Prue H.; Kusel, Merci M. H.

2013-01-01

We tested whether maternal vitamin D insufficiency during pregnancy is related to the autism phenotype. Serum 25(OH)-vitamin D concentrations of 929 women were measured at 18 weeks' pregnancy. The mothers of the three children with a clinical diagnosis of autism spectrum disorder had 25(OH)-vitamin D concentrations above the population mean.…

Effects of Blood-Alcohol Concentration (BAC) Feedback on BAC Estimates Over Time

ERIC Educational Resources Information Center

Bullers, Susan; Ennis, Melissa

2006-01-01

This study examines the effects of self-tested blood alcohol concentration (BAC) feedback, from personal hand-held breathalyzers, on the accuracy of BAC estimation. Using an e-mail prompted web-based questionnaire, 19 participants were asked to report both BAC estimates and subsequently measured BAC levels over the course of 27 days. Results from…

40 CFR Table 4 to Subpart Uuuu of... - Requirements for Performance Tests

Code of Federal Regulations, 2011 CFR

2011-07-01

... 25A if: an exhaust gas volatile organic matter concentration of 50 ppmv or less is required in order to comply with the emission limit; the volatile organic matter concentration at the inlet to the control device and the required level of control are such as to result in exhaust volatile organic matter...

40 CFR Table 4 to Subpart Uuuu of... - Requirements for Performance Tests

Code of Federal Regulations, 2012 CFR

2012-07-01

... 25A if: an exhaust gas volatile organic matter concentration of 50 ppmv or less is required in order to comply with the emission limit; the volatile organic matter concentration at the inlet to the control device and the required level of control are such as to result in exhaust volatile organic matter...

40 CFR Table 4 to Subpart Uuuu of... - Requirements for Performance Tests

Code of Federal Regulations, 2014 CFR

2014-07-01

... 25A if: an exhaust gas volatile organic matter concentration of 50 ppmv or less is required in order to comply with the emission limit; the volatile organic matter concentration at the inlet to the control device and the required level of control are such as to result in exhaust volatile organic matter...

40 CFR Table 4 to Subpart Uuuu of... - Requirements for Performance Tests

Code of Federal Regulations, 2013 CFR

2013-07-01

... 25A if: an exhaust gas volatile organic matter concentration of 50 ppmv or less is required in order to comply with the emission limit; the volatile organic matter concentration at the inlet to the control device and the required level of control are such as to result in exhaust volatile organic matter...

Rumen modulatory effect of thyme, clove and peppermint oils in vitro using buffalo rumen liquor.

PubMed

Roy, Debashis; Tomar, S K; Kumar, Vinod

2015-02-01

The present study was conducted to examine the rumen modulatory effect of thyme, clove and peppermint oils on rumen fermentation pattern in vitro using roughage based diet. Thyme, clove and peppermint oils were tested at concentration of 0, 30, 300 and 600 mg/l (ppm) of total culture fluid using in vitro gas production technique in wheat straw based diet (concentrate: Wheat straw 50:50). Different in vitro parameters e.g., total gas production, methane production, nutrient degradability, volatile fatty acid (VFA) production and ammonia nitrogen concentration were studied using buffalo rumen liquor. Thyme oil at higher dose level (600 ppm) reduced (p<0.05) total gas production, feed degradability and ammonia nitrogen (NH3-N) concentration whereas total VFA concentration was significantly lower (p>0.05) in 300 and 600 ppm dose levels. 600 ppm dose level of clove oil reduced (p<0.05) total gas production, feed degradability, total VFA and acetate to propionate ratio. Methane production was significantly reduced (p<0.05) in 300 and 600 ppm dose levels of clove and peppermint oil. Right combination of these essential oils may prove to enhance performance of animals by reducing methane production and inhibiting protein degradation in rumen.

Modeling extreme PM10 concentration in Malaysia using generalized extreme value distribution

NASA Astrophysics Data System (ADS)

Hasan, Husna; Mansor, Nadiah; Salleh, Nur Hanim Mohd

2015-05-01

Extreme PM10 concentration from the Air Pollutant Index (API) at thirteen monitoring stations in Malaysia is modeled using the Generalized Extreme Value (GEV) distribution. The data is blocked into monthly selection period. The Mann-Kendall (MK) test suggests a non-stationary model so two models are considered for the stations with trend. The likelihood ratio test is used to determine the best fitted model and the result shows that only two stations favor the non-stationary model (Model 2) while the other eleven stations favor stationary model (Model 1). The return level of PM10 concentration that is expected to exceed the maximum once within a selected period is obtained.

Posaconazole in Human Serum: a Greater Pharmacodynamic Effect than Predicted by the Non-Protein-Bound Serum Concentration ▿

PubMed Central

Lignell, Anders; Löwdin, Elisabeth; Cars, Otto; Chryssanthou, Erja; Sjölin, Jan

2011-01-01

It is generally accepted that only the unbound fraction of a drug is pharmacologically active. Posaconazole is an antifungal agent with a protein binding of 98 to 99%. Taking into account the degree of protein binding, plasma levels in patients, and MIC levels of susceptible strains, it can be assumed that the free concentration of posaconazole sometimes will be too low to exert the expected antifungal effect. The aim was therefore to test the activity of posaconazole in serum in comparison with that of the calculated unbound concentrations in protein-free media. Significant differences (P < 0.05) from the serum control were found at serum concentrations of posaconazole of 1.0 and 0.10 mg/liter, with calculated free concentrations corresponding to 1× MIC and 0.1× MIC, respectively, against one Candida lusitaniae strain selected for proof of principle. In RPMI 1640, the corresponding calculated unbound concentration of 0.015 mg/liter resulted in a significant effect, whereas that of 0.0015 mg/liter did not. Also, against seven additional Candida strains tested, there was an effect of the low posaconazole concentration in serum, in contrast to the results in RPMI 1640. Fluconazole, a low-grade-protein-bound antifungal, was used for comparison at corresponding concentrations in serum and RPMI 1640. No effect was observed at the serum concentration, resulting in a calculated unbound concentration of 0.1× MIC. In summary, there was a substantially greater pharmacodynamic effect of posaconazole in human serum than could be predicted by the non-protein-bound serum concentration. A flux from serum protein-bound to fungal lanosterol 14α-demethylase-bound posaconazole is suggested. PMID:21502622

Concentrated affluence, concentrated disadvantage, and children's readiness for school: a population-based, multi-level investigation.

PubMed

Carpiano, Richard M; Lloyd, Jennifer E V; Hertzman, Clyde

2009-08-01

A number of studies demonstrates a relationship between neighbourhood concentration of affluence and disadvantage and the health and development of its residents. We contribute to this literature by testing hypotheses about the relationship between neighbourhood-level concentrated affluence/disadvantage and child-level developmental outcomes in a study population of 37,798 Kindergarten children residing in 433 neighbourhoods throughout the province of British Columbia, Canada. We utilise a previously-validated measure of neighbourhood socioeconomic composition--the Index of Concentration at the Extremes (ICE)--which not only allows for more precise estimation of the competing influences of concentrated affluence and disadvantage, but also facilitates examination of the potential impact of neighbourhood-level income inequality. Our findings show that increases in neighbourhood affluence are associated with increases in children's scores on the Early Development Instrument (EDI), a holistic measure of Kindergarteners' readiness for school. Particularly noteworthy is that, for four of the five EDI scales (physical, social, emotional, and communication) and the total score, results indicate a significant curvilinear relationship--whereby the highest average child-level outcomes are not found in locations with the highest concentrations of affluence, but rather in locations with relatively equal proportions of affluent and disadvantaged families. This finding suggests, first, that concentrated affluence may have diminishing rates of return on contributing to enhanced child development, and, second, that children residing in mixed-income neighbourhoods may benefit both from the presence of affluent residents and from the presence of services and institutions aimed at assisting lower-income residents. Implications and future directions are discussed.

Impurities in silicon solar cells

NASA Technical Reports Server (NTRS)

Hopkins, R. H.

1985-01-01

Metallic impurities, both singly and in combinations, affect the performance of silicon solar cells. Czochralski silicon web crystals were grown with controlled additions of secondary impurities. The primary electrical dopants were boron and phosphorus. The silicon test ingots were grown under controlled and carefully monitored conditions from high-purity charge and dopant material to minimize unintentional contamination. Following growth, each crystal was characterized by chemical, microstructural, electrical, and solar cell tests to provide a detailed and internally consistent description of the relationships between silicon impurity concentration and solar cell performance. Deep-level spectroscopy measurements were used to measure impurity concentrations at levels below the detectability of other techniques and to study thermally-induced changes in impurity activity. For the majority of contaminants, impurity-induced performance loss is due to a reduction of the base diffusion length. From these observations, a semi-empirical model which predicts cell performance as a function of metal impurity concentration was formulated. The model was then used successfully to predict the behavior of solar cells bearing as many as 11 different impurities.

Concentrations and Risks of p-Dichlorobenzene in Indoor and Outdoor Air

PubMed Central

Chin, Jo-Yu; Godwin, Christopher; Jia, Chunrong; Robins, Thomas; Lewis, Toby; Parker, Edith; Max, Paul; Batterman, Stuart

2012-01-01

p-Dichlorobenzene (PDCB) is a chlorinated volatile organic compound (VOC) that can be encountered at high concentrations in buildings due to its use as pest repellent and deodorant. This study characterizes PDCB concentrations in four communities in southeast Michigan. The median concentration outside 145 homes was 0.04 µg m−3, and the median concentration inside 287 homes was 0.36 µg m−3. The distribution of indoor concentrations was extremely skewed. For example, 30% of the homes exceeded 0.91 µg m−3, which corresponds to a cancer risk level of 10−5 based on the California unit risk estimate, and 4% of homes exceeded 91 µg m−3, equivalent to a 10−3 risk level. The single highest measurement was 4,100 µg m−3. Estimates of whole house emission rates were largely consistent with chamber test results in the literature. Indoor concentrations that exceed a few µg m−3 indicate use of PDCB products. PDCB concentrations differed among households and the four cities, suggesting the importance of locational, cultural and behavioral factors in the use patterns of this chemical. The high PDCB levels found suggest the need for policies and actions to lower exposures, e.g., sales or use restrictions, improved labeling, and consumer education. PMID:22725685

Concentration Measurements in a Cold Flow Model Annular Combustor Using Laser Induced Fluorescence

NASA Technical Reports Server (NTRS)

Morgan, Douglas C.

1996-01-01

A nonintrusive concentration measurement method is developed for determining the concentration distribution in a complex flow field. The measurement method consists of marking a liquid flow with a water soluble fluorescent dye. The dye is excited by a two dimensional sheet of laser light. The fluorescent intensity is shown to be proportional to the relative concentration level. The fluorescent field is recorded on a video cassette recorder through a video camera. The recorded images are analyzed with image processing hardware and software to obtain intensity levels. Mean and root mean square (rms) values are calculated from these intensity levels. The method is tested on a single round turbulent jet because previous concentration measurements have been made on this configuration by other investigators. The previous results were used to comparison to qualify the current method. These comparisons showed that this method provides satisfactory results. 'Me concentration measurement system was used to measure the concentrations in the complex flow field of a model gas turbine annular combustor. The model annular combustor consists of opposing primary jets and an annular jet which discharges perpendicular to the primary jets. The mixing between the different jet flows can be visualized from the calculated mean and rms profiles. Concentration field visualization images obtained from the processing provide further qualitative information about the flow field.

A Novel Chronic Opioid Monitoring Tool to Assess Prescription Drug Steady State Levels in Oral Fluid.

PubMed

Shaparin, Naum; Mehta, Neel; Kunkel, Frank; Stripp, Richard; Borg, Damon; Kolb, Elizabeth

2017-11-01

Interpretation limitations of urine drug testing and the invasiveness of blood toxicology have motivated the desire for the development of simpler methods to assess biologically active drug levels on an individualized patient basis. Oral fluid is a matrix well-suited for the challenge because collections are based on simple noninvasive procedures and drug concentrations better correlate to blood drug levels as oral fluid is a filtrate of the blood. Well-established pharmacokinetic models were utilized to generate oral fluid steady state concentration ranges to assess the interpretive value of the alternative matrix to monitor steady state plasma oxycodone levels. Paired oral fluid and plasma samples were collected from patients chronically prescribed oxycodone and quantitatively analyzed by liquid chromatography tandem mass spectrometry. Steady state plasma concentration ranges were calculated for each donor and converted to an equivalent range in oral fluid. Measured plasma and oral fluid oxycodone concentrations were compared with respective matrix-matched steady state ranges, using each plasma steady state classification as the control. A high degree of correlation was observed between matrices when classifying donors according to expected steady state oxycodone concentration. Agreement between plasma and oral fluid steady state classifications was observed in 75.6% of paired samples. This study supports novel application of basic pharmacokinetic knowledge to the pain management industry, simplifying and improving individualized drug monitoring and risk assessment through the use of oral fluid drug testing. Many benefits of established therapeutic drug monitoring in plasma can be realized in oral fluid for patients chronically prescribed oxycodone at steady state. © 2017 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Evaluation of the performance of a micromethod for measuring urinary iodine by using six sigma quality metrics.

PubMed

Hussain, Husniza; Khalid, Norhayati Mustafa; Selamat, Rusidah; Wan Nazaimoon, Wan Mohamud

2013-09-01

The urinary iodine micromethod (UIMM) is a modification of the conventional method and its performance needs evaluation. UIMM performance was evaluated using the method validation and 2008 Iodine Deficiency Disorders survey data obtained from four urinary iodine (UI) laboratories. Method acceptability tests and Sigma quality metrics were determined using total allowable errors (TEas) set by two external quality assurance (EQA) providers. UIMM obeyed various method acceptability test criteria with some discrepancies at low concentrations. Method validation data calculated against the UI Quality Program (TUIQP) TEas showed that the Sigma metrics were at 2.75, 1.80, and 3.80 for 51±15.50 µg/L, 108±32.40 µg/L, and 149±38.60 µg/L UI, respectively. External quality control (EQC) data showed that the performance of the laboratories was within Sigma metrics of 0.85-1.12, 1.57-4.36, and 1.46-4.98 at 46.91±7.05 µg/L, 135.14±13.53 µg/L, and 238.58±17.90 µg/L, respectively. No laboratory showed a calculated total error (TEcalc)

Effects of water-control structures on hydrologic and water-quality characteristics in selected agricultural drainage canals in eastern North Carolina

USGS Publications Warehouse

Treece, M.W.; Jaynes, M.L.

1994-01-01

November of water into and out of tidally affected canals in eastern North Carolina was documented before and after the installation of water-control structures. Water levels in five of the canals downstream from the water-control structures were controlled primarily by water-level fluctuations in estuarine receiving waters. Water-control structures also altered upstream water levels in all canals. Water levels were lowered upstream from tide gates, but increased upstream from flashboard risers. Both types of water-control structures attenuated the release of runoff following rainfall events, but in slightly different ways. Tide gates appeared to reduce peak discharge rates associated with rainfall, and flashboard risers lengthened the duration of runoff release. Tide gates had no apparent effect on pH, dissolved oxygen, suspended-sediment, or total phosphorus concentrations downstream from the structures. Specific conductance measured from composite samples collected with automatic samples increased downstream of tide gates after installation. Median concentrations of nitrite plus nitrate nitrogen were near the minimum detection level throughout the study; however, the number of observations of concentrations exceeding 0.1 milligram per liter dropped significantly after tide gates were installed. Following tide-gate installation, instantaneous loadings of nitrite plus nitrate nitrogen were significantly reduced at one test site, but this reduction was not observed at the other test site. Loadings of other nutrient species and suspended sediment did not change at the tide-gate test sites after tide-gate installation. Specific conductance was lower in the Beaufort County canals than in the Hyde County canals. Although there was a slight increase in median values at the flashboard-riser sites, the mean and maximum values declined substantially downstream from the risers following installation. This decline of specific conductance in the canals occurred despite a large increase of specific conductance in the tidal creek. Flashboard risers had no significant effect on concentrations of dissolved oxygen, suspended sediment, total ammonia plus organic nitrogen, or phosphorus. Maximum concentrations of ammonia nitrogen were smaller at both test sites after riser installation. In addition, concentrations of nitrite plus nitrate nitrogen exceeding 1.0 milligram per liter rarely occurred at the flashboard-riser test sites following installation of the risers. Median loadings of nitrite plus nitrate nitrogen and total nitrogen decreased at one riser test site following flashboard-riser installation. Tide gates and flashboard risers were associated with reductions in concentrations and export of nitrite plus nitrate nitrogen; however, these changes should be interpreted cautiously because reductions were not observed consistently at every site. The hydrology and baseline water-quality characteristics of the two study areas differ, making comparisons of the effectiveness of the two types of water-control structures difficult to interpret. The effects of water-control structures on the hydrology of the drainage canals are more meaningful than the changes in water quality. Tide gates and flashboard risers altered the hydrologic characteristics of the drainage canals and created an environment favorable for nutrient loss or transformation. Both structures retained agricultural drainage upstream, which increased potential storage for infiltration and reduced the potential for surface runoff, sediment, and nutrient transport, and higher peak outflow rates.

Hyperhidrosis plantaris - a randomized, half-side trial for efficacy and safety of an antiperspirant containing different concentrations of aluminium chloride.

PubMed

Streker, Meike; Reuther, Tilmann; Hagen, Linda; Kerscher, Martina

2012-02-01

Primary focal hyperhidrosis plantaris can cause impairment in social, physical, leisure and occupational activities. Topical treatment with aluminium chloride is the first-line treatment. The aim of this trial was to evaluate efficacy and safety of two different concentrations of aluminium chloride hexa-hydrate (12.5%, 30%) for 6 weeks. 20 volunteers with hyperhidrosis plantaris were included. Efficacy was evaluated using a clinical rating scale of the hyperhidrosis level and qualitative assessments including Minor's (iodine-starch) test and a standardized sniff test. Furthermore a patient questionnaire and measurements of skin surface pH were done to evaluate the subjective assessments and side effects. The hyperhidrosis level significantly decreased in both concentrations. There were no differences in tolerability regarding the skin surface pH and the patient questionnaires. In addition the hidrotic areas decreased after application of both products and the sniff test improved. Topical application of an antiperspirant containing aluminium chloride reduced sweat production in plantar hyperhidrosis significantly. As both 12.5% and 30% were efficacious and safe, we would recommend 12.5% for outpatient treatment. © The Author • Journal compilation © Blackwell Verlag GmbH, Berlin.

The effects of reduced oxygen and of carbon monoxide on performance in a mouse pole-jump apparatus

NASA Technical Reports Server (NTRS)

Cagliostro, D. E.; Islas, A.

1982-01-01

The effects on reaction time and behavior were studied for exposure to reduced oxygen concentrations in the presence and absence of carbon monoxide. Tests were run with Swiss Webster mice in a pole-jump apparatus. The results show that reaction times increase gradually with a decrease in oxygen (O2) to 10 percent O2. Below 10 percent O2 reaction times increase dramatically and performance is degraded almost immediately. At carbon monoxide (CO) concentrations of 500 ppm and reduced O2 levels, reaction times are increased even more. At CO concentrations of 1000 ppm, performance is nearly completely degraded even without reduced oxygen levels.

Hydrogeologic monitoring at the Faultless site, Nye County, Nevada

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thordarson, W.

The Faultless event was the detonation of an intermediate-yield nuclear device on January 19, 1968, at a depth of 975 meters below the surface of Hot Creek Valley, Nevada. This report presents details of the hydrogeology and radiochemical monitoring, primarily for the reentry hole UC-1-P-2SR; data from test holes HTH-1, HTH-2, UCE-18, instrument holes UC-1-I-1 and UC-1-I-2, and the abandoned reentry hole UC-1-P-1S are included. The reentry hole UC-1-P-2SR was drilled to a total depth of 1097 meters. The hole penetrated valley-fill sediments above the Tubble Chimney, as well as valley-fill and Tertiary tuffaceous sediments within the rubble chimney andmore » rubble-filled cavity. Monitoring of the water level in the reentry hole indicated that, from 1970-1974, the water level was approximately 694.9 meters in depth below land surface. From 1974 to the present (1983), the water level rose slowly to a depth of 335.1 meters below land surface as the rubble chimney became filled with water. In 1976, the water-level in test hole HTH-1 returned to a depth 6.7 meters above the pre-event water level, and the water level in test hole HTH-2 returned to a depth 2.7 meters above the pre-event water level. Ground water sampled from reentry hole UC-1-P-2SR is a predominantly sodium bicarbonate type containing some sulfate and minor chloride, similar to water from test hole HTH-1. Tritium concentrations fluctuated from a maximum value of 9.2 x 10/sup 8/ picocuries per liter in 1976, decreasing to 10/sup 5/ picocuries per liter in 1977, followed by a gradual increase to values of 10/sup 7/ picocuries per liter from 1980 to 1982. After 1971, gross-beta concentration ranged between 1.2 and 130 picocuries per liter, but generally was less than 10 picocuries per liter. Gross-alpha concentration generally was less than 10 micrograms per liter from 1975 to 1982. 15 refs., 11 figs., 13 tabs.« less

Bactericide effect of methylene blue associated with low-level laser therapy in Escherichia coli bacteria isolated from pressure ulcers.

PubMed

Gomes, Thais Ferreira; Pedrosa, Matheus Masalskiene; de Toledo, Ana Claudia Laforga; Arnoni, Veridiana Wanshi; Dos Santos Monteiro, Mirian; Piai, Davi Cury; Sylvestre, Silvia Helena Zacarias; Ferreira, Bruno

2018-05-09

The present study analyzed the bactericidal effect of methylene blue associated with low-level lasers on Escherichia coli isolated from a pressure ulcer. Microbiological material from a pressure ulcer was isolated using an aseptic swab, and antimicrobial activity was verified using the diffusion disc method. Methylene blue was used at concentrations of 0.001 and 0.005%, and low-level lasers of 670, 830, and 904 nm, with the energy densities of 4, 8, 10, and 14 J/cm 2 , were tested on three plates each and combined with methylene blue of each concentration. In addition, three control plates were used, with each concentration and energy density separated without any interventions. The results were analyzed using the paired sample t test to determine the bactericidal effect of the methylene blue and using the ANOVA test to compare the effects of the energy densities and wavelengths among the low-level laser treatment protocols. The results showed bacterial reduction at wavelengths of 830 and 904 nm and more proliferation in wavelengths of 670 nm. In wavelength of 830 nm, a bacterial reduction was observed in the conditions with 0.001% methylene blue in all energy density utilized, with 0.005% methylene blue in energy density of 10 J/cm 2 , and without methylene blue in energy density at 10 J/cm 2 . And in a wavelength of 904 nm, all condition showed bacterial reduction with or without methylene blue. We concluded that the low-level lasers of 904 and 830 nm have bactericidal effects and at better energy densities (10 and 14 J/cm 2 ).

Accumulation of Heavy Metals in People on a Gluten-Free Diet.

PubMed

Raehsler, Stephanie L; Choung, Rok Seon; Marietta, Eric V; Murray, Joseph A

2018-02-01

Specific foods such as fish and rice have high concentrations of metals such as arsenic, mercury, lead, cadmium, and cobalt. Many gluten-free diets (GFDs) include these foods, so we evaluated whether a GFD was associated with increased metal bioaccumulation. We performed a population-based, cross-sectional study using data collected from the National Health and Nutrition Examination Survey (NHANES), from 2009 through 2012, collecting information on the diagnosis of celiac disease and adherence to a GFD. We tested NHANES blood samples to identify individuals with undiagnosed celiac disease, using assays for immunoglobulin A tissue transglutaminase followed by a confirmatory test for endomysial antibody. Among a total of 11,354 NHANES participants, celiac disease was diagnosed in 55 participants, based on test results or a reported clinical diagnosis. We collected NHANES survey data on blood levels of lead, mercury, and cadmium from subjects who were on a GFD (n = 115) and participants who were not on a GFD (n = 11,239). Levels of total arsenic in urine samples were available from 3901 subjects not following a GFD and 32 individuals following a GFD. NHANES participants were asked questions about fish and shellfish consumption. We performed multivariate logistic regression analyses to associate gluten-related conditions with blood concentrations of mercury, cadmium, and lead and urine concentration of total arsenic, adjusting for demographic characteristics, as well as for rice consumption or seafood intake. Geometric means were reported for urinary concentrations of total arsenic and blood concentrations of mercury, cadmium, and lead for demographic groups and subjects with gluten-related conditions (subjects without celiac disease who avoid gluten). Persons following a GFD had significantly increased total blood mercury levels (1.37 mcg/L) compared with persons not on a GFD (0.93 mcg/L) (P = .008), as well as increased blood levels of lead (1.42 vs 1.13 mcg/L; P = .007) and cadmium (0.42 vs 0.34 mcg/L; P = .03). Urine samples from subjects on a GFD had higher concentrations of total arsenic (15.15 mcg/L) than urine samples from subjects not on a GFD (8.38 mcg/L) (P = .002). After controlling for demographic characteristics, levels of all heavy metals remained significantly higher in persons following a GFD, compared with those not following a GFD. After exclusion of persons with celiac disease, people without celiac disease on a GFD (n = 101) had significantly increased blood concentrations of total mercury (1.40 mcg/L) than persons without celiac disease and not on a GFD (n = 10,890) (0.93 mcg/L; P = .02) and higher blood concentrations of lead (1.44 vs 1.13 mcg/L; P = .01) and higher urine concentrations of total arsenic (14.69 mcg/L [n = 3632] vs 8.32 mcg/L [n = 28]; P = .01). Blood samples from persons without celiac disease avoiding gluten had higher levels of cadmium (0.42 mcg/L) than persons without celiac disease and not following a GFD (0.34 mcg/L), but this difference was not significant (P = .06). In an analysis of data collected from NHANES, persons on a GFD had significantly higher urine levels of total arsenic and blood levels of mercury, lead, and cadmium than persons not avoiding gluten. Studies are needed to determine the long-term effects of accumulation of these elements in persons on a GFD. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

Histologic structure of red nile tilapia fish (Oreochromis nilloticus Var.) gill which is exposed to lead acetate

NASA Astrophysics Data System (ADS)

Utami, N. R.; Widiyaningrum, P.; Iswari, R. S.

2018-03-01

Fish is a water biota commonly used as the bioindicator of water pollution level. One of the animals which are recommended by EPA as the test species is red Nile Tilapia fish (Oreochromis niloticus var). The purpose of this research is to get the value of LC50-96 hours in the toxicity test toward the fishes which are exposed to lead acetate with some details identification of the gills damage by gill histologic structure examination together with the determination of the lead concentration which caused the destruction. Sixty fish were used in the preliminary test to detect the threshold concentration (LC0-48 h); whereas 120 fish were used in the toxicity test to get the mortality level of fish up to 50% in 96 h. Finally, for treatment test, there were 80 fish which were exposed to lead acetate in the concentration of 0 ppm, 259.51 ppm, 291.94 ppm and 324.38 ppm. All the treatment tests were given for four weeks. The data were collected at the end of the 4th week, and then, the description of the fish gill histology structure was done. The histology observation of the fishes gill detected some damages in the form of edema (0% -25%), lamellar fusion (1% -75%), hyperplasia (0% -50%), epithelial lifting (0% -50%), and necrosis (0% -50%). The results indicate that administration of lead acetate accelerates moderate damage to the red Nile tilapia fish gill structure. The greatest level of damage is lamellar fusion, while the other decline damages are edema, hyperplasia, epithelial lifting, and necrosis. Furthermore, it can be concluded that LC50-96 hours value in the lead acetate toxicity test of red Nile tilapia fish is 324,38 ppm with some histologic structure damage in the gill the fishes.

Honey shows potent inhibitory activity against the bovine testes hyaluronidase.

PubMed

Kolayli, Sevgi; Sahin, Huseyin; Can, Zehra; Yildiz, Oktay; Sahin, Kübra

2016-08-01

The purpose of this study was to investigate the anti-hyaluronidase activities of honeys from different botanical origins honeys in order to determine their anti-inflammatory properties. The total phenolic contents, total flavonoids and total tannin levels of six types of honey, chestnut, oak, heather, pine, buckwheat and mixed blossom, were determined. Concentration-related inhibition values were tested turbidimetrically on bovine testis hyaluronidase (BTHase) as IC50 (mg/mL). All honeys exhibited various concentration-dependent degrees of inhibition against BTHase. Inhibition values varied significantly depending on honeys' levels of phenolic contents, flavonoid and tannin. The honeys with the highest anti-hyaluronidase activity were oak, chestnut and heather. In conclusion, polyphenol-rich honeys have high anti-hyaluronidase activity, and these honeys have high protective and complementary potential against hyaluronidase-induced anti-inflammatory failures.

Winery waste recycling through anaerobic co-digestion with waste activated sludge.

PubMed

Da Ros, C; Cavinato, C; Pavan, P; Bolzonella, D

2014-11-01

In this study biogas and high quality digestate were recovered from winery waste (wine lees) through anaerobic co-digestion with waste activated sludge both in mesophilic and thermophilic conditions. The two conditions studied showed similar yields (0.40 m(3)/kgCODfed) but different biological process stability: in fact the mesophilic process was clearly more stable than the thermophilic one in terms of bioprocess parameters. The resulting digestates showed good characteristics for both the tested conditions: heavy metals, dioxins (PCDD/F), and dioxin like bi-phenyls (PCBs) were concentred in the effluent if compared with the influent because of the important reduction of the solid dry matter, but remained at levels acceptable for agricultural reuse. Pathogens in digestate decreased. Best reductions were observed in thermophilic condition, while at 37°C the concentration of Escherichia coli was at concentrations level as high as 1000 UFC/g. Dewatering properties of digestates were evaluated by means of the capillary suction time (CST) and specific resistance to filtration (SRF) tests and it was found that a good dewatering level was achievable only when high doses of polymer (more than 25 g per kg dry solids) were added to sludge. Copyright © 2014 Elsevier Ltd. All rights reserved.

Handheld Device Adapted to Smartphone Cameras for the Measurement of Sodium Ion Concentrations at Saliva-Relevant Levels via Fluorescence

PubMed Central

Lipowicz, Michelle; Garcia, Antonio

2015-01-01

The use of saliva sampling as a minimally-invasive means for drug testing and monitoring physiology is a subject of great interest to researchers and clinicians. This study describes a new optical method based on non-axially symmetric focusing of light using an oblate spheroid sample chamber. The device is simple, lightweight, low cost and is easily attached to several different brands/models of smartphones (Apple, Samsung, HTC and Nokia) for the measurement of sodium ion levels at physiologically-relevant saliva concentrations. The sample and fluorescent reagent solutions are placed in a specially-designed, lightweight device that excludes ambient light and concentrates 470-nm excitation light, from a low-power photodiode, within the sample through non-axially-symmetric refraction. The study found that smartphone cameras and post-image processing quantitated sodium ion concentration in water over the range of 0.5–10 mM, yielding best-fit regressions of the data that agree well with a data regression of microplate luminometer results. The data suggest that fluorescence can be used for the measurement of salivary sodium ion concentrations in low-resource or point-of-care settings. With further fluorescent assay testing, the device may find application in a variety of enzymatic or chemical assays. PMID:28955016

Naturally occurring levels of elements in fishes as determined by PIXE and XRF methods

NASA Astrophysics Data System (ADS)

Tallandini, L.; Giacobini, F.; Turchetto, M.; Galassini, S.; Liu, Q. X.; Shao, H. R.; Moschini, G.; Moro, R.; Gialanella, G.; Ghermandi, G.; Cecchi, R.; Injuk, J.; Valković, V.

1989-04-01

Naturally occurring levels of S, Cl, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Sb, Sr and Pb were measured in the gills, liver and muscles of fishes ( Zosterisessor ophiocephalus Pall) in the northwestern region of the Adriatic Sea. The overall performance of PIXE and XRF methods was tested by the analysis of standard reference materials. The mean concentration values for elements were calculated from the distribution of experimentally determined concentration values. The obtained data are discussed in the framework of metal metabolism and toxicology.

Predicting age at menopause from serum antimüllerian hormone concentration.

PubMed

Tehrani, Fahimeh Ramezani; Shakeri, Nezhat; Solaymani-Dodaran, Masoud; Azizi, Fereidoun

2011-07-01

We aimed to estimate age at menopause using serum antimüllerian hormone (AMH) concentration. We randomly selected 266 study participants from a pool of 1,265 eligible women in the Tehran Lipid and Glucose Study cohort. We measured AMH levels three times at about 3-year intervals. There were 63 occurrences of menopause in our participants over an average of 6-year follow-up. We built an accelerated failure time model using serum AMH level at the start of follow-up to estimate age at menopause. The goodness of fit for the model was tested using Cox-Snell residuals and the Bland-Altman plot. We estimated ages at menopause for different levels of serum AMH concentration among women aged 20 to 49 years. For those who reached menopause, serum AMH concentrations about 6 years before the event provided fairly accurate estimates of the age at menopause. The Bland-Altman plot showed an acceptable agreement between predicted and observed values. Serum AMH concentrations can reasonably forecast the age at menopause for individual women.

HLA phenotypes and cadmium blood level.

PubMed

Gualde, N; Delage, C

1979-10-01

The distribution of HLA phenotypes was studied and the amount of cadmium blood level was determined in a group of 100 healthy subjects. The HLA-A3 phenotype seems associated with high cadmium levels in the blood. The lymphocytes transformation test with PHA and different concentrations of cadmium indicates that A3 cells are more sensitive than others to inhibition by cadmium.

[Effect of starvation on blood protein levels in the population of Dobrinja (1992-1995)].

PubMed

Hasković, E

2000-01-01

In nutritional protein deficiency, numerous studies verified utilization of amino acids generated from tissue degradation in intensive protein synthesis. Unlike liver, muscle protein synthesis is extremely dependent on external supplies of essential amino acids. Prolonged nutritional protein deficiency results in decrease of body weight as well as total protein concentration, in particular in early days of starvation. In prolonged starvation during the war, significant decrease of body weight was registered in 70 subjects while their total protein concentration remained within the expected range and did not significantly differ the values recorded in the control group. Concentration of serum albumines in the control group was lower than the concentration recorded in the tested group, while the serum globulins concentration was higher in the control group. Although the difference in body weight between the tested and the control group was statistically significant, no significant difference in the concentration of total proteins, albumines and globulines was recorded.

Extended analysis of Skylab experiment M558 data

NASA Technical Reports Server (NTRS)

Ukanwa, A. O.

1976-01-01

A careful review of the data from Skylab M558 was made in an effort to explain the apparent anomaly of the existence of radial concentration gradients whereas none should bave been observed. The very close modelling of the experimental axial concentration profiles by the unsteady-state one-dimensional solution of Fick's Law of self-diffusion in liquid zinc, and the condition of initial uniform concentration in the radioactive pellet portion of the experimental specimens would have precluded the appearance of such radial concentration gradients. Statistical analyses were used to test the significance of the observed deviation from radial-concentration homogeneity. A student t-distribution test of significance showed that, at 90% or even at 80% level of significance, there were no significant deviations from uniformity in radial concentrations. It was also concluded that the two likely causes of any deviation that existed were the zinc to zinc-65 bonding procedure and surface phenomena such as surface tension and capillary action.

Occurrence and environmental risk assessment of PAEs in Weihe River near Xi'an City, China.

PubMed

Guo, Xiaofeng; Wang, Lei; Wang, Xudong; Liu, Hanli

2013-01-01

The occurrence and distribution of phthalate acid esters (PAEs) in surface water of the Weihe River basin (eight mainstream sampling points and 15 tributary sampling points) in the Shaanxi section were investigated during the dry season, level period (spring), wet season and level period (autumn). The PAEs tested for were diethyl phthalate (DEP), di-n-butyl phthalate (DBP), dicyclohexyl phthalate (DCHP) and di-(2-ethylhexyl) phthalate (DEHP). The testing proceeded by millipore filtration, then solid phase extraction and then gas chromatography-mass spectrometry determination for all examined PAEs. The monitoring results indicated that, in terms of seasonal changes, concentration of the PAEs in the mainstream is: Dry season > Level period (spring) > Wet season ≈ Level period (autumn). An environmental risk assessment was then performed on PAE pollution levels of the Weihe River basin. This paper employed a risk assessment methodology to evaluate the potential adverse health effects of the individual PAE compounds according to their carcinogenicities. For DEP, DBP and DEHP, a low Risk Index (all of them were lower than the specified level of 1.0) reveals that small non-carcinogenic risks exist resulting from the presence of trace concentrations in the surface water of the Weihe River basin.

Comparison of serum Concentration of Se, Pb, Mg, Cu, Zn, between MS patients and healthy controls

PubMed Central

Alizadeh, Anahita; Mehrpour, Omid; Nikkhah, Karim; Bayat, Golnaz; Espandani, Mahsa; Golzari, Alireza; Jarahi, Lida; Foroughipour, Mohsen

2016-01-01

Introduction Multiple Sclerosis (MS) is defined as one of the inflammatory autoimmune disorders and is common. Its exact etiology is unclear. There are some evidences on the role of environmental factors in susceptible genetics. The aim of this study is to evaluate the possible role of Selenium, Zinc, Copper, Lead and Magnesium metals in Multiple Sclerosis patients. Methods In the present analytical cross-sectional study, 56 individuals including 26 patients and 30 healthy controls were enrolled in the evaluation. The serum level of Se, Zn, Cu, Pb were quantified in graphite furnace conditions and flame conditions by utilizing an atomic absorption Perkin Elmer spectrophotometer 3030. The serum levels of Mg were measured by auto analyzer 1500 BT. The mean level of minerals (Zn, Pb, Cu, Mg, Se) in serum samples were compared in both cases and controls. The mean level of minerals (Zn, Pb, Cu, Mg, Se) in serum samples were compared in both cases and controls by using independent-samples t-test for normal distribution and Mann-Whitney U test as a non-parametric test. All statistical analyses were carried out using SPSS 11.0. Results As well as the Zn, Cu, and Se, there was no significant difference between MS patients and healthy individuals in Pb concentrations (p-value = 0.11, 0.14, 0.32, 0.20 respectively) but the level of Mg was significantly different (p= 0.001). Conclusion All serum concentrations of Zn, Pb, Se, Cu in both groups were in normal ranges and there was no difference in MS patients compared with the healthy group who were matched in genetics. Blood level of Mg was significantly lower in MS patients. But it should be noted that even with the low level of serum magnesium in MS patients, this value is still in the normal range. PMID:27757186

Measurement of salivary aldosterone: validation by low-dose ACTH test and gender differences.

PubMed

Hlavacova, N; Kerlik, J; Radikova, Z; Izakova, L; Jezova, D

2013-10-01

The aim of the present study was to validate the feasibility of measurement of the salivary aldosterone concentrations by performing a low-dose adrenocorticotropic hormone (ACTH) test. Moreover, the presence of gender differences in salivary aldosterone, considering the phase of the menstrual cycle in women, was verified. The sample consisted of 107 volunteers (60 men, 21 women in the follicular phase and 26 women in the luteal phase of the menstrual cycle). Saliva samples were taken by the subjects themselves around 08:00 AM, at least 60 min after awaking. A separate group of female subjects in the follicular phase underwent low-dose ACTH test (1µg synthetic ACTH i.v.) performed at 08:30 AM with blood and saliva sampling every 30 min for 120 min. Modification of the commercial aldosterone radioimmunoassay methodology for the salivary aldosterone measurement was performed. Salivary aldosterone concentrations rose in response to low-dose ACTH test and positive significant correlation in aldosterone concentrations between plasma and saliva was found. The results showed that women in the luteal phase of the menstrual cycle exhibited significantly higher morning concentrations in salivary aldosterone than men and women in the follicular phase. This study clearly demonstrates suitability of measurement of salivary aldosterone concentrations in the low-dose ACTH test and reveals gender differences in salivary aldosterone levels. The results show high validity of the presented method and its usefulness for assessment of the aldosterone concentrations in saliva.

Comparison of laboratory single species and field population-level effects of the pyrethroid insecticide lambda-cyhalothrin on freshwater invertebrates.

PubMed

Schroer, A F W; Belgers, J D M; Brock, T C M; Matser, A M; Maund, S J; Van den Brink, P J

2004-04-01

The toxicity of the pyrethroid insecticide lambda-cyhalothrin to freshwater invertebrates has been investigated using data from short-term laboratory toxicity tests and in situ bioassays and population-level effects in field microcosms. In laboratory tests, patterns of toxicity were consistent with previous data on pyrethroids. The midge Chaoborus obscuripes was most sensitive (48- and 96-h EC50 = 2.8 ng/L). Other insect larvae (Hemiptera, Ephemeroptera) and macrocrustacea (Amphipoda, Isopoda) were also relatively sensitive, with 48- and 96-h EC50 values between 10 and 100 ng/L. Generally, microcrustacea (Cladocera, Copepoda) and larvae of certain insect groups (Odonata and Chironomidae) were less sensitive, with 48-h EC50 values higher than 100 ng/L. Mollusca and Plathelminthes were insensitive and were unaffected at concentrations at and above the water solubility (5 microg/L). Generally, the EC50 values based on initial population responses in field enclosures were similar to values derived from laboratory tests with the same taxa. Also, the corresponding fifth and tenth percentile hazard concentrations (HC5 and HC10) were similar (laboratory HC5 = 2.7 ng/L and field HC5 = 4.1 ng/L; laboratory and field HC10 = 5.1 ng/L), at least when based on the same sensitive taxonomic groups (insects and crustaceans) and when a similar concentration range was taken into account. In the three field enclosure experiments and at a treatment level of 10 ng/L, consistent effects were observed for only one population (Chaoborus obscuripes), with recovery taking place within 3 to 6 weeks. The laboratory HC5 (2.7 ng/L) and HC10 (5.1 ng/L) based on acute EC50 values of all aquatic arthropod taxa were both lower than this 10 ng/L, a concentration that might represent the "regulatory acceptable concentration." The HC5 and HC10 values in this study in The Netherlands (based on static laboratory tests with freshwater arthropods) were very similar to those derived from a previous study in the United Kingdom (1.4 and 3.3 ng/L). This suggests that for pesticides like lambda-cyhalothrin, HC5 values based on static laboratory tests may provide a conservative estimate of the potential for community-level effects under field conditions. While these HC5 values are conservative for initial effects, they do not provide information on recovery potential, which may be important for regulatory decision-making.

In vitro and in vivo characterization of hazelnut skin prick test extracts.

PubMed

Akkerdaas, Jaap H; Wensing, Marjolein; Knulst, André C; Aalberse, Rob C; Hefle, Susan L; van Ree, Ronald

2003-01-01

Hazelnut allergy ranks among the most frequently observed food allergies. Clinical symptoms range from the oral allergy syndrome to life threatening anaphylaxis. Diagnosis of hazelnut allergy partially relies on in vivo testing by means of skin prick testing (SPT). The aim of this study was to characterize hazelnut SPT extracts both in vitro and in vivo. Hazelnut SPT extracts were investigated for protein concentration and composition. The major hazelnut allergen Cor a 1, lipid transfer protein (LTP) and thaumatin-like-protein (TLP) were monitored by competitive RIA and immunoblotting. SPT extracts (n = 6) were analyzed for skin reactivity and the correlation between the SPT extract protein concentration and the mean skin reactivity (HEIC) was determined in a group of hazelnut-allergic patients (n = 30). For one SPT extract, the threshold level for Cor a 1 was determined in Cor a 1-monosensitized patients (n = 5). Protein concentrations ranged from 0.2-14 mg/ml. Although some proteins were present in most extracts (bands at 10, 22-28, 32 and around 48 kDa), clear differences in composition were observed (both intra- and inter-variability). The concentration of the major hazelnut allergen Cor a 1 differed up to a factor 50 (0.6-32 micrograms/ml). LTP was virtually absent in 3/9 SPT extracts and variable quantities of TLP were detected by immunoblotting. Some patients (6/30) had a false-negative SPT with 3/6 SPT extracts. There was a clear correlation between the protein concentration and the mean HEIC (RPearson = 0.87). The threshold level for Cor a 1 was +/- 3.2 ng/ml as assessed with one of the products investigated. Heterogeneous protein concentration/composition of SPT extracts results in variable skin test responses. The absence of potentially severe allergens like LTP may lead to false-negative SPT results that jeopardize a patient's safety. From these results it can be concluded that there is a strong need for standardization of products for SPT.

[Renin-angiotensin-aldosterone system activity during head-up tilt testing in patients with vasovagal syncope].

PubMed

Gajek, Jacek; Zyśko, Dorota; Mazurek, Walentyna

2005-08-01

The stimulation of renin-angiotensin-aldosterone (RAA) system during tilt table test is caused by sympathetic nervous system activation by orthostatic stress and a serotonin release as well. In healthy individuals increase of plasma renin activity during test with maximal values on the peak of the test was described. The aim of the study was to assess the activation of RAAS in patients with neurally mediated syncope during the tilt table test by means of plasma renin activity and serum aldosterone levels. The study was carried out in 31 patients aged 39.4 +/- 15.0 years (18 women and 13 men) with neurally mediated syncope during tilt test. Plasma renin activity was assessed in the baseline conditions, immediately after the test and 10 minutes after the test using radioenzymatic assay. Aldosterone concentrations were measured radioimmunologically, twice: after 30 minutes supine rest and after the syncope. Plasma renin activity during supine rest was 2.2 +/- 2.4 ng/ml/h, rose after the syncope 2.5-fold to 5.2 +/- 4.5 ng/ml/h (p < 0.001 comparing to baseline) stayed on similar level approximately for the next 10 minutes--4.9 +/- 5.5 ng/ml/h (p = n.s.). In 11 patients (35%) 10 minutes after the test even further increase of PRA was observed. Serum aldosterone level increased significantly immediately after tilt test (90.0 +/- 72.9 vs 178.8 +/- 150.1 pg/ml, p < 0.01). Authors showed, that in patients with NMS plasma renin activity increases and this increase lasts for 10 minutes after the syncope and the concentration of aldosterone increases immediately after tilt test.

Report on Advanced Life Support Activities at Kennedy Space Center

NASA Technical Reports Server (NTRS)

Wheeler, Raymond M.

2004-01-01

Plant studies at Kennedy Space Center last year focused on selecting cultivars of lettuce, tomato, and pepper for further testing as crops for near-term space flight applications. Other testing continued with lettuce, onion, and radish plants grown at different combinations of light (PPF), temperature, and CO2 concentration. In addition, comparisons of mixed versus mono culture approaches for vegetable production were studied. Water processing testing focused on the development and testing of a rotating membrane bioreactor to increase oxygen diffusion levels for reducing total organic carbon levels and promoting nitrification. Other testing continued to study composting testing for food wastes (NRA grant) and the use of supplemental green light with red/blue LED lighting systems for plant production (NRC fellowship).

Method for Reduction of Silver Biocide Plating on Metal Surfaces

NASA Technical Reports Server (NTRS)

Steele, John; Nalette, Timothy; Beringer, Durwood

2013-01-01

Silver ions in aqueous solutions (0.05 to 1 ppm) are used for microbial control in water systems. The silver ions remain in solution when stored in plastic containers, but the concentration rapidly decreases to non-biocidal levels when stored in metal containers. The silver deposits onto the surface and is reduced to non-biocidal silver metal when it contacts less noble metal surfaces, including stainless steel, titanium, and nickel-based alloys. Five methods of treatment of contact metal surfaces to deter silver deposition and reduction are proposed: (1) High-temperature oxidation of the metal surface; (2) High-concentration silver solution pre-treatment; (3) Silver plating; (4) Teflon coat by vapor deposition (titanium only); and (5) A combination of methods (1) and (2), which proved to be the best method for the nickel-based alloy application. The mechanism associated with surface treatments (1), (2), and (5) is thought to be the development of a less active oxide layer that deters ionic silver deposition. Mechanism (3) is an attempt to develop an equilibrium ionic silver concentration via dissolution of metallic silver. Mechanism (4) provides a non-reactive barrier to deter ionic silver plating. Development testing has shown that ionic silver in aqueous solution was maintained at essentially the same level of addition (0.4 ppm) for up to 15 months with method (5) (a combination of methods (1) and (2)), before the test was discontinued for nickel-based alloys. Method (1) resulted in the maintenance of a biocidal level (approximately 0.05 ppm) for up to 10 months before that test was discontinued for nickel-based alloys. Methods (1) and (2) used separately were able to maintain ionic silver in aqueous solution at essentially the same level of addition (0.4 ppm) for up to 10 months before the test was discontinued for stainless steel alloys. Method (3) was only utilized for titanium alloys, and was successful at maintaining ionic silver in aqueous solution at essentially the same level of addition (0.4 ppm) for up to 10 months before the test was discontinued for simple flat geometries, but not for geometries that are difficult to Teflon coat.

Influence of the dentinal wall on the pH of sodium hypochlorite during root canal irrigation.

PubMed

Macedo, Ricardo Gomes; Herrero, Noemi Pascual; Wesselink, Paul; Versluis, Michel; van der Sluis, Luc

2014-07-01

The purpose of this study was to evaluate the influence of dentin on the pH levels of different concentrations of sodium hypochlorite (NaOCl) solutions over time and to evaluate if preconditioning of dentin with 17% EDTA or agitation of the NaOCl solution influences these pH levels. A novel clinically representative model that scales with the ratio of the irrigant volume to the dentin surface area of a human root canal was used. Three standardized bovine dentin bars (2 × 2 × 10 mm) were placed in a plastic test tube. A total of 150 tubes were distributed in 29 groups. In the first experiment, the pH of various NaOCl solutions, with different concentrations (3%, 6%, and 9%) and starting pH levels (5 and 12), was monitored during exposure to dentin between 10 and 300 seconds. In a second experiment, the effect of agitation (45 Hz) and pretreatment of dentin with 17% EDTA on the pH levels of various NaOCl solutions was studied after 30 seconds of exposure to dentin. The short-term chemical stability of the tested solutions was assessed for both the concentration and the pH. The exposure time (P < .001) and concentration of the NaOCl solution (P < .011) significantly influence the pH level after exposure to dentin. However, the change in pH is too small to induce a change in the irrigant antimicrobial/tissue dissolution capacity. Agitation of the irrigant and preconditioning of the dentin did not alter the pH (P > .05). Both the pH 5 and pH 12 solutions were chemically stable for 1 hour. Copyright © 2014 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Toxicity of granular activated carbon treated coal gasification water as determined by the Microtox test and Escherichia coli.

PubMed

Makino, Y; Adams, J C; McTernan, W F

1986-01-01

The Microtox assay and various parameters (growth, ATP concentration and electrochemical detection) of Escherichia coli were used to assess the toxicity of various levels of granular activated carbon treated coal gasification process water. The generation time of E. coli was statistically significantly slower at the level of 50 percent treatment than any other level of treatment. No differences were seen for ATP concentration per cell or in the electrochemical detection methods for any level treatment. There was a very high correlation between total organic carbon removal by GAC treatment and reduction in toxicity as measured by the Microtox system. However, even the treated water which had 91 percent of the TOC removed was still highly toxic.

Building materials used in construction can affect indoor fungal levels greatly.

PubMed

Ellringer, P J; Boone, K; Hendrickson, S

2000-01-01

This article summarizes the results of a fungal investigation of a new, seven-story, 170-room hotel. The owners of the building were refused an occupancy permit by local building officials because of concerns about fungal contamination. This article discusses the processes that were used to investigate and abate the fungal concerns in this building. This investigation involved comparing fungal infestation levels in various building materials, including two different types of gypsum wallboard. During initial testing the indoor air concentrations of problematic fungi were up to 50 times higher than outdoor levels. After the removal of the fungal-infested materials and the replacement with more acceptable materials, the indoor air concentration of problematic fungi dropped to less than one-fourth of outdoor levels.

Relationship between serum adiponectin concentration, body condition score, and peripheral tissue insulin response of dairy cows during the dry period.

PubMed

De Koster, J; Urh, C; Hostens, M; Van den Broeck, W; Sauerwein, H; Opsomer, G

2017-04-01

The aim of the present study was to describe the relationship between serum adiponectin concentration and peripheral tissue insulin response in dairy cows with a variable body condition score (BCS) during the dry period. Cows were selected at the beginning of the dry period based on BCS (BCS <3.75, n = 4; BCS >3.75, n = 5). Animals were followed from the beginning of the dry period by weekly blood sampling and assessment of BCS and backfat thickness. Weekly blood samples were analyzed for adiponectin concentration using a bovine specific ELISA. Hyperinsulinemic euglycemic clamp tests were performed at the end of the dry period to measure peripheral tissue insulin response. Insulin dose response curves were established for both glucose and fatty acid metabolism. Regression analysis revealed that the serum concentrations of adiponectin dropped at the end of the dry period (P < 0.05) and were negatively associated with BCS (P < 0.05). At the level of the glucose metabolism, serum concentrations of adiponectin were positively correlated with insulin responsiveness (reflecting the maximal effect of insulin; r = 0.76, P < 0.05), but not with insulin sensitivity (reflecting the insulin concentration needed to achieve halfmaximal effect; r = -0.54, P = 0.13). At the level of the fatty acid metabolism, greater adiponectin concentrations were negatively correlated with lower NEFA levels during the HEC test reflecting the insulin responsiveness of the NEFA metabolism (r = -0.61, P = 0.08), whereas there was no association with the insulin sensitivity of the NEFA metabolism (r = -0.16, P = 0.67). In conclusion, serum concentrations of adiponectin were negatively associated with the BCS of dairy cows during the dry period and positively associated with insulin responsiveness of the glucose and fatty acid metabolism. Copyright © 2016 Elsevier Inc. All rights reserved.

Survey of Indoor Radon Concentrations in California Elementary Schools. Final Report.

ERIC Educational Resources Information Center

Zhou, Joey Y.; Liu, Kai-Shen; Waldman, Jed

This paper reports on the concentrations of radon found within a sample of 378 elementary schools in California. Long-term alpha-track radon detectors were placed in 6,485 classrooms within participating schools to detect radon levels for between 220 to 366 days. Only classrooms were tested. Results show that about 5.6 percent of the schools…

Children's environmental chemical exposures in the USA, NHANES 2003-2012.

PubMed

Hendryx, Michael; Luo, Juhua

2018-02-01

Children are vulnerable to environmental chemical exposures, but little is known about the extent of multiple chemical exposures among children. We analyzed biomonitoring data from five cycles (2003-2012) of the National Health and Nutrition Examination Survey (NHANES) to describe multiple chemical exposures in US children, examine levels of chemical concentrations present over time, and examine differences in chemical exposures by selected demographic groups. We analyzed data for 36 chemical analytes across five chemical classes in a sample of 4299 children aged 6-18. Classes included metals, pesticides, phthalates, phenols, and polycyclic aromatic hydrocarbons. We calculated the number and percent of chemicals detected and tested for secular trends over time in chemical concentrations. We compared log concentrations among groups defined by age, sex, race/ethnicity, and poverty using multiple linear regression models and report adjusted geometric means. Among a smaller subgroup of 733 children with data across chemical classes, we calculated the linear correlations within and between classes and conducted a principal component analysis. The percentage of children with detectable concentrations of an individual chemical ranged from 26 to 100%; the average was 93%, and 29 of 36 were detected in more than 90% of children. Concentrations of most tested chemicals were either unchanged or declined from earlier to more recent years. Many differences in concentrations were present by age, sex, poverty, and race/ethnicity categories. Within and between class correlations were all significant and positive, and the principal component analysis suggested a one factor solution, indicating that children exposed to higher levels of one chemical were exposed to higher levels of other chemicals. In conclusion, children in the USA are exposed to multiple simultaneous chemicals at uneven risk across socioeconomic and demographic groups. Further efforts to understand the effects of multiple exposures on child health and development are warranted.

Secondhand smoke exposure and risk following the Irish smoking ban: an assessment of salivary cotinine concentrations in hotel workers and air nicotine levels in bars

PubMed Central

Mulcahy, M; Evans, D; Hammond, S; Repace, J; Byrne, M

2005-01-01

Objective: To investigate whether the Irish smoking ban has had an impact on secondhand smoke (SHS) exposures for hospitality workers. Design, setting, and participants: Before and after the smoking ban a cohort of workers (n = 35) from a sample of city hotels (n = 15) were tested for saliva cotinine concentrations and completed questionnaires. Additionally, a random sample (n = 20) of city centre bars stratified by size (range 400–5000 square feet), were tested for air nicotine concentrations using passive samplers before and after the ban. Main outcome measures: Salivary cotinine concentrations (ng/ml), duration of self reported exposures to secondhand smoke, air nicotine (µg/cubic metre). Results: Cotinine concentrations reduced by 69%, from 1.6 ng/ml to 0.5 ng/ml median (SD 1.29; p < 0.005). Overall 74% of subjects experienced decreases (range 16–99%), with 60% showing a halving of exposure levels at follow up. Self reported exposure to SHS at work showed a significant reduction from a median 30 hours a week to zero (p < 0.001). There was an 83% reduction in air nicotine concentrations from median 35.5 µg/m3 to 5.95 µg/m3 (p < 0.001). At baseline, three bars (16%) were below the 6.8 µg/m3 air nicotine significant risk level for lung cancer alone; at follow up this increased to 10 (53%). Conclusions: Passive smoking and associated risks were significantly reduced but not totally eliminated. Exposure to SHS is still possible for those working where smoking is still allowed and those working where smoke may migrate from outdoor areas. Further research is required to assess the true extent and magnitude of these exposures. PMID:16319361

Secondhand smoke exposure and risk following the Irish smoking ban: an assessment of salivary cotinine concentrations in hotel workers and air nicotine levels in bars.

PubMed

Mulcahy, M; Evans, D S; Hammond, S K; Repace, J L; Byrne, M

2005-12-01

To investigate whether the Irish smoking ban has had an impact on secondhand smoke (SHS) exposures for hospitality workers. Before and after the smoking ban a cohort of workers (n = 35) from a sample of city hotels (n = 15) were tested for saliva cotinine concentrations and completed questionnaires. Additionally, a random sample (n = 20) of city centre bars stratified by size (range 400-5000 square feet), were tested for air nicotine concentrations using passive samplers before and after the ban. Salivary cotinine concentrations (ng/ml), duration of self reported exposures to secondhand smoke, air nicotine (microg/cubic metre). Cotinine concentrations reduced by 69%, from 1.6 ng/ml to 0.5 ng/ml median (SD 1.29; p < 0.005). Overall 74% of subjects experienced decreases (range 16-99%), with 60% showing a halving of exposure levels at follow up. Self reported exposure to SHS at work showed a significant reduction from a median 30 hours a week to zero (p < 0.001). There was an 83% reduction in air nicotine concentrations from median 35.5 microg/m3 to 5.95 microg/m3 (p < 0.001). At baseline, three bars (16%) were below the 6.8 microg/m3 air nicotine significant risk level for lung cancer alone; at follow up this increased to 10 (53%). Passive smoking and associated risks were significantly reduced but not totally eliminated. Exposure to SHS is still possible for those working where smoking is still allowed and those working where smoke may migrate from outdoor areas. Further research is required to assess the true extent and magnitude of these exposures.

Levels of polychlorinated biphenyls and organochlorine pesticides in some edible marine organisms from the Central Adriatic Sea.

PubMed

Perugini, M; Cavaliere, M; Giammarino, A; Mazzone, P; Olivieri, V; Amorena, M

2004-11-01

Concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCs) were found in tissue of marine organisms such as Mediterranean mussel, Norway lobster, red mullet, common cuttle-fish, European flying squid, European anchovy, European pilchard and Atlantic mackerel, coming from two sites along the Abruzzo coast of the Adriatic Sea. Species were selected due to their habitat, trophic level, feeding behaviour and their use in the Italian diet. Mussels, filter feeder and sedentary organisms, were used in order to test water pollution whereas Norway lobster and red mullet (benthic fish) were used in order to test sediment pollution. The concentration of ?PCBs exceeded that of ?OCs in the samples analysed. The highest concentrations of ?PCBs (1415 ng/g lipid weight) and ?OCs (507 ng/g lipid weight) were found in pilchard while the lowest concentrations of the same pollutants were found in cephalopods. Our results have shown that species such as anchovy, pilchard and mackerel, were the most polluted due to their location at the last level of the trophic chain. All samples contained different concentrations of PCBs and among these, congeners 153 and 138 were the most representative. Among the OCs, except for the cuttle-fish, the highest concentrations were found for p,p(')-DDE and p,p(')-DDD that are metabolite of DDT. The prevailing DDE presence, compared to DDT (high DDE/DDT ratio), suggested that the biotransformation rate of pollutants was very efficacious in fish and above all in crustaceans. Results have also been interpreted in terms of geographical distribution and organisms' biological cycle. None of the samples analysed exceeded the tolerance limits established by the OCs Italian legislation.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoogheem, T.J.; Woods, L.A.

The Monsanto Analytical Testing (MAT) program was devised and implemented in order to provide analytical standards to Monsanto manufacturing plants involved in the self-monitoring of plant discharges as required by National Pollutant Discharge Elimination System (NPDES) permit conditions. Standards are prepared and supplied at concentration levels normally observed at each individual plant. These levels were established by canvassing all Monsanto plants having NPDES permits and by determining which analyses and concentrations were most appropriate. Standards are prepared by Monsanto's analyses and concentrations were most appropriate. Standards are prepared by Monsanto's Environmental Sciences Center (ESC) using Environmental Protection Agency (EPA) methods.more » Eleven standards are currently available, each in three concentrations. Standards are issued quarterly in a company internal round-robin program or on a per request basis or both. Since initiation of the MAT program in 1981, the internal round-robin program has become an integral part of Monsanto's overall Good Laboratory Practices (GLP) program. Overall, results have shown that the company's plant analytical personnel can accurately analyze and report standard test samples. More importantly, such personnel have gained increased confidence in their ability to report accurate values for compounds regulated in their respective plant NPDES permits. 3 references, 3 tables.« less

The identification of Volatile Organic Compound's emission sources in indoor air of living spaces, offices and laboratories

NASA Astrophysics Data System (ADS)

Kultys, Beata

2018-01-01

Indoor air quality is important because people spend most of their time in closed rooms. If volatile organic compounds (VOCs) are present at elevated concentrations, they may cause a deterioration in human well-being or health. The identification of indoor emission sources is carried out by comparison indoor and outdoor air composition. The aim of the study was to determinate the concentration of VOCs in indoor air, where there was a risk of elevated levels due to the kind of work type carried out or the users complained about the symptoms of a sick building followed by an appropriate interpretation of the results to determine whether the source of the emission in the tested room occurs. The air from residential, office and laboratory was tested in this study. The identification of emission sources was based on comparison of indoor and outdoor VOCs concentration and their correlation coefficients. The concentration of VOCs in all the rooms were higher or at a similar level to that of the air sampled at the same time outside the building. Human activity, in particular repair works and experiments with organic solvents, has the greatest impact on deterioration of air quality.

Measurement of rivaroxaban concentrations demonstrates lack of clinical utility of a PT, dPT and APTT test in estimating levels.

PubMed

Thom, I; Cameron, G; Robertson, D; Watson, H G

2018-05-02

Rivaroxaban concentrations were measured in 127 inpatient samples using an HPLC-MS/MS assay. We compared this measurement with a calibrated anti-Xa assay and performed PT, aPTT and dilute PT tests to assess the value of clot-based assays in clinical decision-making. The correlation between the anti-Xa assay and the HPLC-MS/MS at therapeutic concentrations was strong (R 2  = 0.98). The PT, RecombiPlasTin 2G, and aPTT, Actin FS, showed a linear dose-response but poor correlation (R 2  = 0.32 and 0.44, respectively) and at dilutions of 1 in 150 to 1 in 750 the dilute PT assay also showed poor correlation with rivaroxaban concentrations measured by specific assays. A normal PT or aPTT alone did not identify a likely safe rivaroxaban concentration to allow surgery or invasive procedures, but the combination of normal PT and aPTT identified a group of patients with rivaroxaban levels less than 90 ng/mL. Combined normal PT and aPTT had specificity and sensitivity of 0.97 (95% CI 0.92-0.99) and 0.37 (95% CI 0.1-0.74) for a rivaroxaban concentration < 32 ng/mL. The PT and aPTT show poor correlation with rivaroxaban levels measured by calibrated anti-Xa and HPLC-MS/MS assays. A normal combined PT and APTT identified low rivaroxaban levels with high specificity but lacked sensitivity. The dPT assay at several dilutions could not be used to quantify rivaroxaban in clinical samples. The utility of these PT, aPTT and dilute PT assays in a clinical setting is very limited, and results generated must be interpreted with caution. © 2018 John Wiley & Sons Ltd.

Study on OELs for enzyme-containing detergent in China.

PubMed

Zhang, X D; Liang, Y X; Lee, C S; Jin, T Y

2004-01-01

This study is aimed at setting occupational exposure levels for total detergent dust and enzymes in detergent industries. The study population consisted of 795 workers from four enzyme-containing detergent manufacturing plants (A1, A2, B1 and B2), and 156 control workers from an electronic assembly factory. Work environment monitoring was conducted using high volume of air sampler fro measuring the concentration of total dust (mg/m3), and analyzing the level of enzyme (ng/m3) by ELISA method. A standard questionnaires, pulmonary function test, and skin prick test are used to assess health effects. The levels of detergent total dust varied from 0.2 mg/m3 to 12.54 mg/m3. For enzyme levels, in A1, B1 and B2, the concentration ranged from non-detectable to 9.92 ng/m3 and in A2, the concentration was analyzed by enzyme activity methods and was expressed as Gu/m3 (1 Gu/m3 = 16 ng/m3). The concentration is between 0.16-31.36 ng/m3. Non-specific irritation rates in exposed workers were significantly higher than that in controls. Based on the data collected from A1, B1 and control plants, 95% benchmark dose lower bound were calculated as 1.17 mg/m3. The difference of pulmonary function between exposed workers and controls is not significant. The results of SPT showed that neither Savinase- nor Alcalase-induced sensitization was found in controls. The prevalence rates of sensitization for Savinase and Alcalase were ranged between 3.2% and 31% in all enzyme-containing detergent manufacturers investigated. No case of occupational asthma was observed. For total dust, 1 mg/m3 is suggested as permissible concentration-time weighted average (PC-TWA), and 2 mg/m3 as permissible concentration-short term exposure limit (PC-STEL). For the enzyme Subtilisins, 15 ng/m3 is suggested as PC-TWA, and 30 ng/m3 as PC-STEL.

Prediction of hamstring injury in professional soccer players by isokinetic measurements

PubMed Central

Dauty, Marc; Menu, Pierre; Fouasson-Chailloux, Alban; Ferréol, Sophie; Dubois, Charles

2016-01-01

Summary Objectives previous studies investigating the ability of isokinetic strength ratios to predict hamstring injuries in soccer players have reported conflicting results. Hypothesis to determine if isokinetic ratios are able to predict hamstring injury occurring during the season in professional soccer players. Study Design case-control study; Level of evidence: 3. Methods from 2001 to 2011, 350 isokinetic tests were performed in 136 professional soccer players at the beginning of the soccer season. Fifty-seven players suffered hamstring injury during the season that followed the isokinetic tests. These players were compared with the 79 uninjured players. The bilateral concentric ratio (hamstring-to-hamstring), ipsilateral concentric ratio (hamstring-to-quadriceps), and mixed ratio (eccentric/concentric hamstring-to-quadriceps) were studied. The predictive ability of each ratio was established based on the likelihood ratio and post-test probability. Results the mixed ratio (30 eccentric/240 concentric hamstring-to-quadriceps) <0.8, ipsilateral ratio (180 concentric hamstring-to-quadriceps) <0.47, and bilateral ratio (60 concentric hamstring-to-hamstring) <0.85 were the most predictive of hamstring injury. The ipsilateral ratio <0.47 allowed prediction of the severity of the hamstring injury, and was also influenced by the length of time since administration of the isokinetic tests. Conclusion isokinetic ratios are useful for predicting the likelihood of hamstring injury in professional soccer players during the competitive season. PMID:27331039

Primary prevention of pediatric lead exposure requires new approaches to transfusion screening.

PubMed

Gehrie, Eric; Keiser, Amaris; Dawling, Sheila; Travis, James; Strathmann, Frederick G; Booth, Garrett S

2013-09-01

To facilitate further assessment of transfusion-associated lead exposure by designing a procedure to test packed red blood cells (pRBCs) prepared for transfusion. The relationship between pRBCs and whole blood lead concentration was investigated in 27 samples using a modified clinical assay. Lead concentrations were measured in 100 pRBC units. Our sample preparation method demonstrated a correlation between whole blood lead and pRBC lead concentrations (R(2) = 0.82). In addition, all 100 pRBC units tested had detectable lead levels. The median pRBC lead concentration was 0.8 μg/dL, with an SD of 0.8 μg/dL and a range of 0.2-4.1 μg/dL. In addition, after only a few days of storage, approximately 25% of whole blood lead was found in the supernatant plasma. Transfusion of pRBCs is a source of lead exposure. Here we report the quantification of lead concentration in pRBCs. We found a >20-fold range of lead concentrations in the samples tested. Pretransfusion testing of pRBC units according to our proposed approach or donor screening of whole blood lead and selection of below-average units for transfusion to children would diminish an easily overlooked source of pediatric lead exposure. Copyright © 2013 Mosby, Inc. All rights reserved.

Analysis of Metal Contents in Portland Type V and MTA-Based Cements

PubMed Central

Dorileo, Maura Cristiane Gonçales Orçati; Bandeca, Matheus Coelho; Pedro, Fábio Luis Miranda; Volpato, Luiz Evaristo Ricci; Guedes, Orlando Aguirre; Villa, Ricardo Dalla; Tonetto, Mateus Rodrigues; Borges, Alvaro Henrique

2014-01-01

The aim of this study was to determine, by Atomic Absorption Spectrometry (AAS), the concentration levels of 11 metals in Type V gray and structural white PC, ProRoot MTA, and MTA Bio. Samples, containing one gram of each tested cement, were prepared and transferred to a 100 mL Teflon tube with a mixture of 7.0 mL of nitric acid and 21 mL of hydrochloric acid. After the reaction, the mixture was filtered and then volumed to 50 mL of distilled water. For each metal, specific patterns were determined from universal standards. Arsenic quantification was performed by hydride generator. The analysis was performed five times and the data were statistically analyzed at 5% level of significance. Only the cadmium presented concentration levels of values lower than the quantification limit of the device. The AAS analysis showed increased levels of calcium, nickel, and zinc in structural white PC. Type V PC presented the greatest concentration levels of arsenic, chromium, copper, iron, lead, and manganese (P < 0.05). Bismuth was found in all cements, and the lowest concentration levels were observed in Portland cements, while the highest were observed in ProRoot MTA. Both PC and MTA-based cements showed evidence of metals inclusion. PMID:25436238

Nandrolone excretion is not increased by exhaustive exercise in trained athletes.

PubMed

Schmitt, Nelly; Flament, Marie-Madeleine; Goubault, Claude; Legros, Patrick; Grenier-Loustalot, Marie France; Denjean, André

2002-09-01

The anabolic steroid nandrolone is widely used as a performance enhancer. Traces of its naturally occurring metabolite 19-norandrosterone (19-NA) have been found in human urine (below 0.6 ng.mL(-1)), and it has been suggested that strenuous exercise may increase urinary 19-NA. The aim of our study was to assess the effect of exhaustive exercise on the nandrolone excretion under controlled conditions in two groups of trained male athletes, one composed of judoka and the other of long-distance runners. A Wingate test and a treadmill limited-time test (running at 85% (.)VO(2max)) were carried out on 14 judoka and 15 athletes. Hydration was controlled during each session. Urine samples were obtained before each test and 30 min, 60 min, and 24 h after each test. Urinary 19-NA concentrations were determined using gas chromatography coupled with mass spectrometry. Baseline urinary 19-NA concentrations varied widely across individuals, from undetectable levels to 0.250 ng.mL (-1)(mean, 0.048 +/- 0.050 ng.mL(-1)). The both exercise tests did not significantly modified urinary 19-NA levels in the two groups of subjects. Our study provides compelling evidence that endogenous nandrolone production in male athletes, during two very different types of exercise, produces urine levels far below the IOC threshold of 2 ng.mL(-1) urine. Thus, exercise does not induce endogenous nandrolone secretion.

An Increase in Healthcare-Associated Clostridium difficile Infection Associated with Use of a Defective Peracetic Acid-Based Surface Disinfectant.

PubMed

Cadnum, Jennifer L; Jencson, Annette L; O'Donnell, Marguerite C; Flannery, Elizabeth R; Nerandzic, Michelle M; Donskey, Curtis J

2017-03-01

BACKGROUND We investigated an increase in the incidence of healthcare-associated Clostridium difficile infection (CDI) that occurred following a change from a bleach disinfectant to a peracetic acid-based disinfectant. OBJECTIVE To evaluate the efficacy of the peracetic acid-based disinfectant. DESIGN Laboratory-based product evaluation. METHODS The commercial peracetic acid-based product is activated on site by mixing a small volume of concentrated hydrogen peroxide and peracetic acid present in a "SmartCap" reservoir with the remaining contents of the container. We measured concentrations of peracetic acid in newly activated and in-use product and determined the stability of nonactivated and activated product. We tested the efficacy of the product against C. difficile spores using the American Society for Testing and Materials standard quantitative carrier disk test method. RESULTS Measured concentrations of peracetic acid (50-800 parts per million [ppm]) were significantly lower than the level stated on the product label (1,500 ppm), and similar results were obtained for containers from multiple lot numbers and from another hospital. Product with peracetic acid levels below 600 ppm had significantly reduced activity against C. difficile spores. Peracetic acid concentrations were reduced markedly after storage of either activated or nonactivated product for several weeks. The Environmental Protection Agency confirmed the finding of low disinfectant levels and ordered discontinuation of sale of the product. CONCLUSION Use of a defective peracetic acid-based surface disinfectant may have contributed to an increase in healthcare-associated CDI. Our findings highlight the importance of evaluating the efficacy of liquid disinfectants in healthcare settings. Infect Control Hosp Epidemiol 2017;38:300-305.

Level of contamination with mycobiota and contents of mycotoxins from the group of trichothecenes in grain of wheat , oats, barley, rye and triticale harvested in Poland in 2006- 2008.

PubMed

Stuper-Szablewska, Kinga; Perkowski, Juliusz

2017-03-01

The risk of cereal exposure to microbial contamination is high and possible at any time, starting from the period of plant vegetation, through harvest, up to the processing, storage and transport of the final product. Contents of mycotoxins in grain are inseparably connected with the presence of fungal biomass, the presence of which may indicate the occurrence of a fungus, and indirectly also products of its metabolism. Analyses were conducted on 378 grain samples of wheat, triticale, barley, rye and oats collected from grain silos located at grain purchase stations and at mills in Poland in 2006, 2007 and 2008. The concentrations of ERG and mycotoxins from the group of trichothecenes, as well as CFU numbers were analysed. The tested cereals were characterised by similarly low concentrations of both the investigated fungal metabolites and the level of microscopic fungi. However, conducted statistical analyses showed significant variation between tested treatments. Oat and rye grain contained the highest amounts of ERG, total toxins and CFU. In turn, the lowest values of investigated parameters were found in grain of wheat and triticale. Chemometric analyses, based on the results of chemical and microbiological tests, showed slight differences between contents of analysed metabolites between the years of the study, and do not confirm the observations on the significance of the effect of weather conditions on the development of mycobiota and production of mycotoxins; however, it does pertain to treatments showing no significant infestation. Highly significant correlations between contents of trichothecenes and ERG concentration (higher than in the case of the correlation of the total toxin concentrations/log cfu/g), indicate that the level of this metabolite is inseparably connected with mycotoxin contents in grain.

Physical conditions of a house and their effects on measured radon levels: data from Hillsborough Township, New Jersey, 2010-2011.

PubMed

Shendell, Derek G; Carr, Michael

2013-10-01

Concentrations of radon in homes are thought to be dependent on several factors, including the presence of certain physical conditions of the house that act as entry points for this colorless, odorless gas. Drains and sump pits are currently sealed as part of radon mitigation, but doing so may cause drainage problems and mold. The authors attempted to determine if specific attributes and physical conditions of homes are associated with measured residential concentrations of radon. Radon tests were conducted in 96 participating homes in rural Hillsborough Township, New Jersey, November 2010-February 2011. Samplers were placed and a walk-through survey was conducted. Test devices were analyzed by a New Jersey certified radon testing laboratory and results compared to survey data. Overall, 50% of houses with a perimeter drain and 30% of houses with a sump pit exceeded the New Jersey and federal radon action level of 4.0 picocuries per liter, and 47% of homes with both a sump and a perimeter "French" drain exceeded this action level. The authors' results suggested certain physical conditions act as pathways allowing radon entry into homes. Results could be used by local and state agencies to start local initiatives, e.g., increased testing or to seal these components as partial mitigation.

The relation of cortisol and sex hormone levels to results of psychological, performance, IQ and memory tests in military men and women.

PubMed

Flegr, Jaroslav; Hampl, Richard; Černochová, Dana; Preiss, Marek; Bičíková, Marie; Sieger, Ladislav; Příplatová, Lenka; Kaňková, Šárka; Klose, Jiří

2012-01-01

Cortisol, along with other hormones of hypothalamo-pituitary-adrenal axis, belongs to one of the main factors influencing psychological and pathognomic factors, intelligence, and memory. The aim of our study was to review a large battery of psychological, performance, IQ and memory tests as to their relation with cortisol, testosterone and estrogen levels in groups of 100 men and 93 women who attended the Central Military Hospital in Prague for regular entrance psychological examinations for military personnel. In men, we detected positive correlations between cortisol and emotional lability, and negative correlations with impulsivity, while in women hypochondria and psychopathology were negatively correlated, and aggression measured with the Meili selective memory test had a positive relation to cortisol level. Testosterone correlated positively with emotional liability and negatively with impulsivity in men, and negatively with hypochondria and psychasteny, indirect aggression, irritability and paranoia in women. Estradiol correlated positively with psychopathology in men, and negatively with phobia. It was positively correlated with negativism in women. No clear correlation was observed between the concentration of steroid hormones and psychomotor performance or intelligence. Concentrations of steroid hormones correlate with results of several psychological tests, the sign and magnitude of these correlations, however, very often differ in military men and women.

Further characterization of an aversive learning task in Drosophila melanogaster: intensity of the stimulus, relearning, and use of rutabaga mutants.

PubMed

Perisse, Emmanuel; Portelli, Geoffrey; Le Goas, Solène; Teste, Elsa; Le Bourg, Eric

2007-11-01

Various learning tasks have been described in Drosophila melanogaster, flies being either tested in groups or at the individual level. Le Bourg and Buecher (Anim Learn Behav 33:330-341, 2002) have designed a task at the individual level: photopositive flies crossing a T-maze learn to prefer the dark exit when the lighted one is associated with the presence of aversive stimuli (humidity and quinine). Previous studies have reported various results (e.g. no effect of age) and the present article further characterizes this task by studying the possible effects of: (1) the intensity of the stimuli (quantity of water or concentration of quinine), (2) various delays between two learning sessions on the learning score at the second session, (3) the rutabaga learning mutation on the learning score. More concentrated quinine solutions increased learning scores but the quantity of water had no effect. Learning scores at the second session were higher with shorter delays between the two learning sessions and retrograde amnesia could decrease this memory score. rutabaga mutants showed learning deficits as in experiments testing groups of flies. This learning task could particularly be used to verify whether learning mutants isolated after experiments testing flies in groups display similar deficits when tested at the individual level.

An Approach to Developing the Laboratory Through Senior Design Projects.

ERIC Educational Resources Information Center

Faghri, Amir

1987-01-01

Describes a program in which senior engineering students are given the opportunity to design, make, and test apparatus intended for an upper-level teaching laboratory. Discusses such projects as a vapor compressor test stand with refrigerant mass flow measurement, a double-walled concentric annular heat pipe, and a vacuum filling station. (TW)

Feasibility Assessment of a Structurally Closable, Automatable Technique, for the Deglycerolization of Frozen RBC (Human). Phase 2

DTIC Science & Technology

1996-04-01

to biocompatible levels. associated with collection, testing , inventory and trans- Thawed cells are processed in order to reduce both the glycerol... tested . The instrument is capable of prediluting and washing up to two units of blood per tube set. Our results show that when the performance of our...concentration of glycerol has to be reduced to biocompatible levels (from 1.57 M to less than 0.1 M). Freezing and thawing red blood cells leads to

Crop uptake and extractability of cadmium in soils naturally high in metals at different pH levels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Singh, B.R.; Almas, A.; Narwal, R.P.

1995-12-01

A greenhouse experiment was conducted for three years to study the effect of different pH levels on metal concentrations in plants and the cadmium (Cd) extractability by DTPA and NH{sub 4}NO{sub 3}. The soils used were an alum shale (clay loam) and a moraine (loam), which were adjusted to pH levels of 5.5, 6.5, 7.0, and 7.5. Wheat (Triticum aestivum), carrot (Daucus carota L.), and lettuce (Lactuca sativa) were grown as test crops. Crop yields were not consistently affected at increasing soil pH levels. The concentration of Cd in plant species decreased with increasing soil pH in both soils andmore » in all three years. Significant concentration differences between soil pH levels were only seen in wheat and carrot crops. Increasing soil pH also decreased the nickel (Ni) and zinc (Zn) concentrations in plants in the first year crop but the copper (Cu) concentration was not consistently affected by soil pH. The effect of pH was more pronounced in the moraine then the alum shale soil. The DTPA-and NH{sub 4}NO{sub 3}-extractable Cd was decreased with the increasing soil pH and the pH effect was more pronounced with NH{sub 4}NO{sub 3} extractable Cd. Both extractants were found equally effective in relation to the Cd concentration in plants in this study. 33 refs., 2 figs., 7 tabs.« less

Pesticide-contaminated feeds in integrated grass carp aquaculture: toxicology and bioaccumulation.

PubMed

Pucher, J; Gut, T; Mayrhofer, R; El-Matbouli, M; Viet, P H; Ngoc, N T; Lamers, M; Streck, T; Focken, U

2014-02-19

Effects of dissolved pesticides on fish are widely described, but little is known about effects of pesticide-contaminated feeds taken up orally by fish. In integrated farms, pesticides used on crops may affect grass carp that feed on plants from these fields. In northern Vietnam, grass carp suffer seasonal mass mortalities which may be caused by pesticide-contaminated plants. To test effects of pesticide-contaminated feeds on health and bioaccumulation in grass carp, a net-cage trial was conducted with 5 differently contaminated grasses. Grass was spiked with 2 levels of trichlorfon/fenitrothion and fenobucarb. Unspiked grass was used as a control. Fish were fed at a daily rate of 20% of body mass for 10 d. The concentrations of fenitrothion and fenobucarb in pond water increased over time. Effects on fish mortality were not found. Fenobucarb in feed showed the strongest effects on fish by lowering feed uptake, deforming the liver, increasing blood glucose and reducing cholinesterase activity in blood serum, depending on feed uptake. Fenobucarb showed increased levels in flesh in all treatments, suggesting bio-concentration. Trichlorfon and fenitrothion did not significantly affect feed uptake but showed concentration-dependent reduction of cholinesterase activity and liver changes. Fenitrothion showed bioaccumulation in flesh which was dependant on feed uptake, whereas trichlorfon was only detected in very low concentrations in all treatments. Pesticide levels were all detected below the maximum residue levels in food. The pesticide-contaminated feeds tested did not cause mortality in grass carp but were associated with negative physiological responses and may increase susceptibility to diseases.

Elevated α-Hydroxybutyrate and Branched-Chain Amino Acid Levels Predict Deterioration of Glycemic Control in Adolescents.

PubMed

Tricò, Domenico; Prinsen, Hetty; Giannini, Cosimo; de Graaf, Robin; Juchem, Christoph; Li, Fangyong; Caprio, Sonia; Santoro, Nicola; Herzog, Raimund I

2017-07-01

Traditional risk factors for type 2 diabetes mellitus are weak predictors of changes in glucose tolerance and insulin sensitivity in youth. To identify early metabolic features of insulin resistance (IR) in youth and whether they predict deterioration of glycemic control. A cross-sectional and longitudinal study was conducted at the Yale Pediatric Obesity Clinic. Concentrations of α-hydroxybutyrate, β-hydroxybutyrate, lactate, and branched-chain amino acids (BCAAs) were measured by nuclear magnetic resonance spectroscopy in 78 nondiabetic adolescents during an oral glucose tolerance test (OGTT). Associations between baseline metabolic alterations and longitudinal changes in glucose control were tested in 16 subjects after a mean follow-up of 2.3 years. The relationship between metabolite levels, parameters of IR, and glycemic control, and their progression over time. Elevated fasting α-hydroxybutyrate levels were observed in adolescents with reduced insulin sensitivity after adjusting for age, sex, ethnicity, Tanner stage, and body mass index z-score (P = 0.014). Plasma α-hydroxybutyrate and BCAAs were increased throughout the course of the OGTT in this group (P < 0.03). Notably, borderline IR was associated with a progressive α-hydroxybutyrate decrease from elevated baseline concentrations to normal levels (P = 0.02). Increased baseline α-hydroxybutyrate concentrations were further associated with progressive worsening of glucose tolerance and disposition index. α-Hydroxybutyrate and BCAA concentrations during an OGTT characterize insulin-resistant youth and predict worsening of glycemic control. These findings provide potential biomarkers for risk assessment of type 2 diabetes and new insights into IR pathogenesis. Copyright © 2017 Endocrine Society

The effects of periodontal therapy on intracrevicular prostaglandin E2 concentrations and clinical parameters in pregnancy.

PubMed

Yalcin, Funda; Basegmez, Cansu; Isik, Gulden; Berber, Lacin; Eskinazi, Esti; Soydinc, Mahtaban; Issever, Halim; Onan, Utku

2002-02-01

The increase in circulating levels of progesterone during pregnancy stimulates production of prostaglandins, especially prostaglandin E2, possibly resulting in pregnancy gingivitis. The purpose of this study is to evaluate the influence of prostaglandin E2 concentrations on gingival tissues in pregnancy and to assess its relationship to clinical parameters. This study evaluates the effects of periodontal treatment on clinical indices including plaque index, gingival index, probing depth, and gingival crevicular fluid prostaglandin E2 levels of 22 pregnant women in their first, second, and third trimesters. Initial periodontal therapy consisting of scaling, root planing, and oral hygiene instruction was performed at the beginning of the first trimester and repeated each trimester. Prostaglandin E2 concentrations in gingival crevicular fluid were determined using a commercially available enzyme immunoassay kit. The statistical tests used were paired sample test and correlation analysis. The results of the study show that periodontal therapy has resulted in an improvement in clinical parameters (P<0.05). There is also a statistically significant decrease in levels of prostaglandin E2 at the second and third trimesters following periodontal therapy (P <0.001). The correlation between prostaglandin E2 concentrations and clinical parameters is found to be non-significant (P >0.05). Our data indicate that levels of prostaglandin E2 in gingival crevicular fluid may be used as a marker of gingival inflammation in order to determine the effects of periodontal therapy in pregnancy. Periodontal therapy that is performed throughout the entire pregnancy period may help prevent the threat of pregnancy gingivitis.

Sensitivity test of derivative matrix isopotential synchronous fluorimetry and least squares fitting methods.

PubMed

Makkai, Géza; Buzády, Andrea; Erostyák, János

2010-01-01

Determination of concentrations of spectrally overlapping compounds has special difficulties. Several methods are available to calculate the constituents' concentrations in moderately complex mixtures. A method which can provide information about spectrally hidden components in mixtures is very useful. Two methods powerful in resolving spectral components are compared in this paper. The first method tested is the Derivative Matrix Isopotential Synchronous Fluorimetry (DMISF). It is based on derivative analysis of MISF spectra, which are constructed using isopotential trajectories in the Excitation-Emission Matrix (EEM) of background solution. For DMISF method, a mathematical routine fitting the 3D data of EEMs was developed. The other method tested uses classical Least Squares Fitting (LSF) algorithm, wherein Rayleigh- and Raman-scattering bands may lead to complications. Both methods give excellent sensitivity and have advantages against each other. Detection limits of DMISF and LSF have been determined at very different concentration and noise levels.

Bile acids induce arrhythmias in human atrial myocardium--implications for altered serum bile acid composition in patients with atrial fibrillation.

PubMed

Rainer, Peter P; Primessnig, Uwe; Harenkamp, Sandra; Doleschal, Bernhard; Wallner, Markus; Fauler, Guenter; Stojakovic, Tatjana; Wachter, Rolf; Yates, Ameli; Groschner, Klaus; Trauner, Michael; Pieske, Burkert M; von Lewinski, Dirk

2013-11-01

High bile acid serum concentrations have been implicated in cardiac disease, particularly in arrhythmias. Most data originate from in vitro studies and animal models. We tested the hypotheses that (1) high bile acid concentrations are arrhythmogenic in adult human myocardium, (2) serum bile acid concentrations and composition are altered in patients with atrial fibrillation (AF) and (3) the therapeutically used ursodeoxycholic acid has different effects than other potentially toxic bile acids. Multicellular human atrial preparations ('trabeculae') were exposed to primary bile acids and the incidence of arrhythmic events was assessed. Bile acid concentrations were measured in serum samples from 250 patients and their association with AF and ECG parameters analysed. Additionally, we conducted electrophysiological studies in murine myocytes. Taurocholic acid (TCA) concentration-dependently induced arrhythmias in atrial trabeculae (14/28 at 300 µM TCA, p<0.01) while ursodeoxycholic acid did not. Patients with AF had significantly decreased serum levels of ursodeoxycholic acid conjugates and increased levels of non-ursodeoxycholic bile acids. In isolated myocytes, TCA depolarised the resting membrane potential, enhanced Na(+)/Ca(2+) exchanger (NCX) tail current density and induced afterdepolarisations. Inhibition of NCX prevented arrhythmias in atrial trabeculae. High TCA concentrations induce arrhythmias in adult human atria while ursodeoxycholic acid does not. AF is associated with higher serum levels of non-ursodeoxycholic bile acid conjugates and low levels of ursodeoxycholic acid conjugates. These data suggest that higher levels of toxic (arrhythmogenic) and low levels of protective bile acids create a milieu with a decreased arrhythmic threshold and thus may facilitate arrhythmic events.

Effects of nutrient management on nitrate levels in ground water near Ephrata Pennsylvania

USGS Publications Warehouse

Hall, David W.

1992-01-01

Effects of the implementation of nutrient management practices on ground-water quality were studied at a 55-acre farm in Lancaster County, Pennsylvania, from 1985-90. After nutrient management practices were implemented at the site in October 1986, statistically significant decreases (Wilcoxon Mann-Whitney test) in median nitrate concentrations in ground-water samples occurred at four of the five wells monitored. The largest decreases in nitrate concentration occurred in samples collected at the wells that had the largest nitrate concentrations prior to nutrient management. The decreases in median nitrate concentrations in ground-water samples ranged from 8 to 32 percent of the median concentrations prior to nutrient management and corresponded to nitrogen application decreases of 39 to 67 percent in contributing areas that were defined upgradient of these wells. Changes in nitrogen applications to the contributing areas of five water wells were correlated (Spearman rank-sum test) with nitrate concentrations of the well water. Changes in ground-water nitrate concentrations lagged behind the changes in applied-nitrogen fertilizers (primarily manure) by approximately 4 to 19 months.

Mixotrophy in Heterocapsa rotundata: A Mechanism for Dominating the Winter Phytoplankton Community

NASA Astrophysics Data System (ADS)

Millette, N.; Pierson, J. J.; Aceves, A.; Stoecker, D.

2016-02-01

Heterocapsa rotundata is a dinoflagellate that forms large winter blooms in estuaries and coastal ecosystems. Past research has focused on the mechanisms necessary for these winter blooms to form but it is unknown why H. rotundata consistently forms these blooms. H. rotundata is a known mixotroph, and we conducted grazing experiments with a non-axenic culture of H. rotundata containing bacteria to test what environmental conditions increase H. rotundata's community grazing rate. We used microspheres to confirm that H. rotundata was grazing. We measured the change of bacterial abundance in control (without grazers) and experimental groups over 24 hours to estimate H. rotundata's community grazing rate on bacteria at different irradiance levels and ammonium concentrations. There was a significant interaction between the effect of ammonium concentration and irradiance levels. As irradiance levels decreased, the effect of ammonium concentrations on H. rotundata grazing rates became less pronounced. At lower irradiance levels H. rotundata grazing rates remained high, regardless of the ammonium concentration. Overall, changes in irradiance levels had a larger impact on H. rotundata grazing rates than changes in ammonium concentration. The findings will be discussed in light of ongoing lab and field research. The winter season is known for limiting light levels that most likely have a negative impact on phytoplankton growth rates. Heterocapsa rotundata has adapted to low light levels by increasing grazing on bacteria to consume enough carbon to maintain growth. Heterocapsa rotundata's response to low light levels is likely the mechanism that provides the competitive advantage to form winter blooms under the right conditions over other phytoplankton species.

The Association Between MCT1 T1470A Polymorphism and Power-Oriented Athletic Performance.

PubMed

Kikuchi, N; Fuku, N; Matsumoto, R; Matsumoto, S; Murakami, H; Miyachi, M; Nakazato, K

2017-01-01

The purpose of this study was to investigate the effects of the MCT1 T1470A polymorphism (rs1049434) on power-oriented performance and lactate concentration during or after cycling sprints in Japanese wrestlers. Participants (199 wrestlers and 649 controls) were genotyped for the MCT1 T1470A genotype (rs1049434) using the TaqMan ® Assay. All wrestlers were international (n=77) or national (n=122) level athletes. Among them, 46 wrestlers performed 2 anaerobic performance tests, a 30-s Wingate Anaerobic test (WAnT) and a series of 10 maximal effort 10-s sprints on a cycle ergometer. Blood lactate levels were measured before, during, and after the tests. In the A-allele recessive model (AA vs. TA+TT), the frequency of the AA genotype was significantly higher in all wrestlers than in controls (p=0.037). Wrestlers with AA genotype had lower blood lactate concentrations than those with TA+TT genotype at 10 min after the WAnT and following the 5 th and the final set of repeated cycling sprints (p<0.05). The AA genotype of the MCT1 T1470A polymorphism is over-represented in wrestlers compared with controls and is associated with lower blood lactate concentrations after 30-s WAnT and during intermittent sprint tests in Japanese wrestlers. © Georg Thieme Verlag KG Stuttgart · New York.

Relationship between intracranial pressure and antifungal agents levels in the CSF of patients with cryptococcal meningitis.

PubMed

Wirth, Fernanda; de Azevedo, Maria Isabel; Pilla, Carmen; Aquino, Valério Rodrigues; Neto, Gustavo Wissmann; Goldani, Luciano Zubaran

2018-04-01

The purpose of this study was to evaluate the influence of intracranial hypertension in the cerebrospinal fluid (CSF) levels of amphotericin B and fluconazole levels of patients with cryptococcal meningitis. CSF samples and intracranial pressure were obtained by means of routine punctures performed at days 1, 7, and 14 of therapy, respectively. Amphotericin B and fluconazole CSF levels were measured by HPLC method as previously described. The minimum inhibitory concentration for amphotericin B, fluconazole, 5΄flucytosine, and voriconazole of each Cryptococcus isolate was performed according to CLSI. The predominant Cryptococcus species found was C. neoformans, and the major underlying condition was AIDS. Only one CSF sample had a detectable level for amphotericin B during the 14 days of therapy. Fluconazole CSF levels progressively increased from day 1 to day 14 of therapy for most cases. Fluconazole levels in the CSF were above the minimum inhibitory concentrations (MICs) for Cryptococcus during the initial 14 days of antifungal therapy. Variations of intracranial pressure did not affect amphotericin B and fluconazole levels in the CSF. The generalized estimating correlation (GEE) and Spearman correlation test (SCT) showed no significant correlation between the amphotericin B or fluconazole concentrations in the CSF and intracranial pressure (P = .953 and P = .093, respectively for GEE test and P = .477 and P = .847, respectively, for SCT). Combination therapy of amphotericin B with fluconazole was effective in 60% of the patients considering CSF cultures were negative in 9 of 15 patients after 14 days of therapy. Further studies are necessary to evaluate the role of intracranial hypertension on the therapeutic efficacy of different antifungal agents in patients with cryptococcal meningitis.

Effects of the anti-fouling herbicide Irgarol 1051 on two life stages of the grass shrimp, Palaemonetes pugio.

PubMed

Key, Peter B; Chung, Katy W; Hoguet, Jennifer; Sapozhnikova, Yelena; Fulton, Michael H

2008-01-01

This study investigated lethal and sublethal effects (glutathione, lipid peroxidation, cholesterol, and acetylcholinesterase) of the anti-fouling herbicide Irgarol 1051 on larval and adult grass shrimp (Palaemonetes pugio). The 96-hour LC50 test for larvae resulted in an estimated LC50 of 1.52 mg/L (95% confidence interval [CI] 1.26-1.85 mg/L). The adult 96-h LC50 was 2.46 mg/L (95% CI = 2.07-2.93 mg/L). Glutathione, lipid peroxidation, cholesterol and acetylcholinesterase levels were not significantly affected in adult grass shrimp by exposure of up to 3.00 mg/L irgarol. Lipid peroxidation and acetylcholinesterase levels in the larvae were significantly higher than controls in the highest irgarol exposures of 1.0 and 2.0 mg/L, respectively. Cholesterol levels were significantly reduced in larvae in all four irgarol concentrations tested while glutathione levels were not significantly affected in larvae. Both lethal and sublethal effects associated with irgarol exposure were only observed at concentrations well above those reported in the environment.

Crude oil contaminated soil washing in air sparging assisted stirred tank reactor using biosurfactants.

PubMed

Urum, Kingsley; Pekdemir, Turgay; Ross, David; Grigson, Steve

2005-07-01

This study investigated the removal of crude oil from soil using air sparging assisted stirred tank reactors. Two surfactants (rhamnolipid and sodium dodecyl sulfate, SDS) were tested and the effects of different parameters (i.e. temperature, surfactant concentrations, washing time, volume/mass ratio) were investigated under varying washing modes namely, stirring only, air sparging only and the combination of stirring and air sparging. The results showed that SDS removed more than 80% crude oil from non-weathered soil samples, whilst rhamnolipid showed similar oil removal at the third and fourth levels of the parameters tested. The oil removal ability of the seawater prepared solutions were better than those of the distilled water solutions at the first and second levels of temperature and concentration of surfactant solutions. This approach of soil washing was noted to be effective in reducing the amount of oil in soil. Therefore we suggested that a field scale test be conducted to assess the efficiency of these surfactants.

The Effect of Biduri (Calotropis gigantean) Latex on Meat Quality of Post Laying Hen

NASA Astrophysics Data System (ADS)

Nuhriawangsa, A. M. P.; Swastike, W.; Hertanto, B. S.; W, A.; Pradisha, E. D.

2017-04-01

The aim of this research was to investigate the effect of biduri (Calotropis gigantean) latex treatment on physical quality and hedonic test of meat of post laying hen. Samples of this research used meat of post laying hen strain Lohman aged 90 weeks. Thigh muscle was used for physical quality and breast muscle for hedonic test. Extract of biduri latex were obtained by cutting and tapping of young stem tissue, and it was centrifuged to obtain crude fluid of biduri latex (supernatant). Variables of this research were pH, cooking loss, tenderness, and water holding capacity (WHC), and hedonic test. Levels of biduri latex were 0, 3, 6 and 9% were measured from weight of the samples and the treatment of biduri latex by smearing on the surface of meat samples. The experimental design of the research used one way randomized design. The data was analyzed by using ANOVA, and differences between treatment means were further analysed using Duncan’s New Multiple Range Test. The effect of biduri latex did not affect on pH, but it significantly affected on cooking loss, WHC, tenderness, and hedonic test (p<0.01). Cooking loss started to decrease in concentration of 6%. Value of WHC and tenderness went up at concentration of 3%. Increasing of meat quality of tenderness of hedonic test, juicy and overall hedonic test started to increase in concentration of 6%, and also flavor on concentration of 3% and 9%. In conclusion, the treatment of biduri latex with concentration of 3% could increase meat quality of meat of post laying hen.

Color vision impairment with low-level methylmercury exposure of an Amazonian population - Brazil.

PubMed

Feitosa-Santana, Claudia; Souza, Givago da Silva; Sirius, Esaú Ventura Pupo; Rodrigues, Anderson Raiol; Cortes, Maria Izabel Tentes; Silveira, Luiz Carlos de Lima; Ventura, Dora Fix

2018-05-01

Land exploitation that follows deforestation and mining can result in soil erosion and the release of mercury to the waters of rivers in the Amazon Basin. Inorganic mercury is methylated by bacteria that are present in the environment and it serves as a source of human contamination through fish consumption in the form of methylmercury. Long-term exposure to low-level methylmercury in the riverside populations can lead to nervous system alterations, some of which are visual impairments such as loss of luminance contrast sensitivity, restricted visual fields and color vision defects. The present study sought to examine color vision in a group of adults living in the central Brazilian Amazon who were exposed to low-levels of methylmercury. Total Hg concentrations were measured from hair collected at the time of the testing. The D15d and FM100 color vision arrangement tests were applied in a population of 36 (22 males) and 42 (25 males), respectively. Controls were healthy volunteers from the cities of São Paulo for the D15d and Belém for the FM100. There was a statistically significant difference in performance between those who were exposed and controls for both tests (p < 0.01 and p < 0.0001, respectively, Mann-Whitney U test), meaning that adults living in this region of the Amazon made more mistakes on both tests when compared to controls. A linear regression was performed using Hg concentrations and test scores. Hg concentrations accounted for 7% and 2% of color D15d and FM100 arrangement test errors, respectively. Although other studies have previously found color vision impairment in the Amazon, they tested inhabitants on the east side of the Amazon, while this study was conducted in the central Amazon region and it is the first study in a population with no direct contact with the Hg source of contamination. These results suggest that long-term exposure to low-level methylmercury in riverside populations is more widely spread in the Amazon Basin than previously reported. This information is needed to implement public health policies that will ensure a safer environment for the Amazonian population. Copyright © 2018 Elsevier B.V. All rights reserved.

A flow-proteometric platform for analyzing protein concentration (FAP): Proof of concept for quantification of PD-L1 protein in cells and tissues.

PubMed

Chou, Chao-Kai; Huang, Po-Jung; Tsou, Pei-Hsiang; Wei, Yongkun; Lee, Heng-Huan; Wang, Ying-Nai; Liu, Yen-Liang; Shi, Colin; Yeh, Hsin-Chih; Kameoka, Jun; Hung, Mien-Chie

2018-05-29

Protein expression level is critically related to the cell physiological function. However, current methodologies such as Western blot (WB) and Immunohistochemistry (IHC) in analyzing the protein level are rather semi-quantitative and without the information of actual protein concentration. We have developed a microfluidic technique termed a "flow-proteometric platform for analyzing protein concentration (FAP)" that can measure the concentration of a target protein in cells or tissues without the requirement of a calibration standard, e.g., the purified target molecules. To validate our method, we tested a number of control samples with known target protein concentrations and showed that the FAP measurement resulted in concentrations that well matched the actual concentrations in the control samples (coefficient of determination [R 2 ], 0.998), demonstrating a dynamic range of concentrations from 0.13 to 130 pM of a detection for 2 min. We successfully determined a biomarker protein (for predicting the treatment response of cancer immune check-point therapy) PD-L1 concentration in cancer cell lines (HeLa PD-L1 and MDA-MB-231) and breast cancer patient tumor tissues without any prior process of sample purification and standard line construction. Therefore, FAP is a simple, faster, and reliable method to measure the protein concentration in cells and tissues, which can support the conventional methods such as WB and IHC to determine the actual protein level. Copyright © 2018 Elsevier B.V. All rights reserved.

Detection of fibrin generation alterations in dogs with haemangiosarcoma using resonance thrombography.

PubMed

Mischke, R; Wohlsein, P; Schoon, H-A

2005-01-01

The objective of the study was to examine the alterations of fibrin generation in dogs with haemangiosarcoma using resonance thrombography. The second objective was to evaluate the sensitivity of this method for the detection of hypofibrinogenaemia and/or increased fibrin(ogen) degradation product (FDP) concentration. Resonance thrombogram (RTG) measurements with two different instruments were performed in 30 unselected dogs with haemangiosarcoma, 14 of which had decreased fibrinogen and 28 of which had an increased FDP concentration (p<0.0001). The RTG-reaction time was less sensitive than the fibrin formation time (RTG-f) and fibrin amplitude (RTG-F). The RTG-f and RTG-F indicated reliably a decrease in fibrinogen concentration (sensitivity: 0.93). The sensitivity of detection of increased FDP levels was considerably higher than that of thrombin time. However, false-negative results were found even at FDP concentrations > or =120 mg/l, especially in cases with high fibrinogen level. Both machines showed similar sensitivity. The results of this study indicate that canine haemangiosarcoma is frequently associated with severe alterations of fibrin generation due to low fibrinogen and high FDP levels leading to distinct RTG abnormalities. The global test RTG reacts sensitively to a decreased fibrinogen level whereas its accuracy to detect FDP concentrations occurring under pathophysiological conditions is limited. A significant alteration of fibrin generation induced by FDPs may not occur until the serum FDP concentration exceeds 60 mg/l.

Development and evaluation of a regression-based model to predict cesium-137 concentration ratios for saltwater fish.

PubMed

Pinder, John E; Rowan, David J; Smith, Jim T

2016-02-01

Data from published studies and World Wide Web sources were combined to develop a regression model to predict (137)Cs concentration ratios for saltwater fish. Predictions were developed from 1) numeric trophic levels computed primarily from random resampling of known food items and 2) K concentrations in the saltwater for 65 samplings from 41 different species from both the Atlantic and Pacific Oceans. A number of different models were initially developed and evaluated for accuracy which was assessed as the ratios of independently measured concentration ratios to those predicted by the model. In contrast to freshwater systems, were K concentrations are highly variable and are an important factor in affecting fish concentration ratios, the less variable K concentrations in saltwater were relatively unimportant in affecting concentration ratios. As a result, the simplest model, which used only trophic level as a predictor, had comparable accuracies to more complex models that also included K concentrations. A test of model accuracy involving comparisons of 56 published concentration ratios from 51 species of marine fish to those predicted by the model indicated that 52 of the predicted concentration ratios were within a factor of 2 of the observed concentration ratios. Copyright © 2015 Elsevier Ltd. All rights reserved.

Study on Leucaena leocochepala seed during fermentation : sensory characteristic and changes on anti nutritional compounds and mimosine level

NASA Astrophysics Data System (ADS)

Nursiwi, A.; Ishartani, D.; Sari, AM; Nisyah, K.

2018-01-01

Lamtoro (Leucaena leucocephala) seed is one of the leguminosae which have high level of protein but it contains toxic compound such as mimosine and some anti nutritional compounds such as phitic acid and tannin. The objectives of the research was to investigate the sensory characteristic and the changes onanti nutritional compounds and mimosine level in Leucaena leucochepala seed during fermentation. Lamtoro tempeh processing was carried out by boiling the seed, crushing to separate the hull, soaking, boiling, and fermentation. The best concentration inoculum in lamtoro tempeh processing was determined by hedonic test. Fermentation was carried out in 36 hours and every 6 hours mimosine, tannin, and phitic acid content was analyzed. From hedonic test, inoculum concentration of 1% was used in lamtoro tempeh processing. During 36 hours fermentation, phytic acid content and mimosine content was decreased significantly, from 0.0558 % to 0.0453 % and from 0.00393 % to 0.00173 % respectively. Whereas tannin content was increased signifacantly, from 0.0822 % to 0.00173 %.

The Influence of Tobacco Smoke on Protein and Metal Levels in the Serum of Women during Pregnancy

PubMed Central

Wrześniak, Marta; Kepinska, Marta; Królik, Małgorzata; Milnerowicz, Halina

2016-01-01

Background Tobacco smoking by pregnant women has a negative effect on fetal development and increases pregnancy risk by changing the oxidative balance and microelements level. Smoking affects the concentration, structure and function of proteins, potentially leading to various negative effects on pregnancy outcomes. Methodology/Principal Findings The influence of tobacco smoke on key protein fractions in smoking and non-smoking healthy pregnant women was determined by capillary electrophoresis (CE). Concentrations of the proteins α1-antitrypsin, α1-acid glycoprotein, α2-macroglobulin and transferrin were determined by ELISA tests. Total protein concentration was measured by the Biuret method. Smoking status was established by cotinine levels. Cadmium (Cd) and Zinc (Zn) concentrations were determined by flame atomic absorption spectrometry and the Zn/Cd ratio was calculated based on these numbers. Smoking women had a 3.7 times higher level of Cd than non-smoking women. Zn levels decreased during pregnancy for all women. The Zn/Cd ratio was three times lower in smoking women. The differences between the changes in the protein profile for smoking and non-smoking women were noted. Regarding proteins, α1-antitrypsin and α2-macroglobulin levels were lower in the non-smoking group than in the smoking group and correlated with Cd levels (r = -0.968, p = 0.032 for non-smokers; r = −0.835, p = 0.019 for smokers). Zn/Cd ratios correlated negatively with α1-, α2- and β-globulins. Conclusions/Significance Exposure to tobacco smoke increases the concentration of Cd in the blood of pregnant women and may lead to an elevated risk of pregnancy disorders. During pregnancy alter concentrations of some proteins. The correlation of Cd with proteins suggests that it is one of the causes of protein aberrations. PMID:27548057

Modelling and analysis of ozone concentration by artificial intelligent techniques for estimating air quality

NASA Astrophysics Data System (ADS)

Taylan, Osman

2017-02-01

High ozone concentration is an important cause of air pollution mainly due to its role in the greenhouse gas emission. Ozone is produced by photochemical processes which contain nitrogen oxides and volatile organic compounds in the lower atmospheric level. Therefore, monitoring and controlling the quality of air in the urban environment is very important due to the public health care. However, air quality prediction is a highly complex and non-linear process; usually several attributes have to be considered. Artificial intelligent (AI) techniques can be employed to monitor and evaluate the ozone concentration level. The aim of this study is to develop an Adaptive Neuro-Fuzzy inference approach (ANFIS) to determine the influence of peripheral factors on air quality and pollution which is an arising problem due to ozone level in Jeddah city. The concentration of ozone level was considered as a factor to predict the Air Quality (AQ) under the atmospheric conditions. Using Air Quality Standards of Saudi Arabia, ozone concentration level was modelled by employing certain factors such as; nitrogen oxide (NOx), atmospheric pressure, temperature, and relative humidity. Hence, an ANFIS model was developed to observe the ozone concentration level and the model performance was assessed by testing data obtained from the monitoring stations established by the General Authority of Meteorology and Environment Protection of Kingdom of Saudi Arabia. The outcomes of ANFIS model were re-assessed by fuzzy quality charts using quality specification and control limits based on US-EPA air quality standards. The results of present study show that the ANFIS model is a comprehensive approach for the estimation and assessment of ozone level and is a reliable approach to produce more genuine outcomes.

Tissue deposition of polychlorinated biphenyls in cats fed Atlantic Ocean bluefish.

PubMed

Carbone, L G; Alo, D K; Scarlett, J M; Gutenmann, W H; Lisk, D J

1991-07-01

Bluefish (Pomatomus saltatrix), a very popular marine sport fish caught in Atlantic coastal waters, contain significant levels of polychlorinated biphenyls (PCBs). Since fish can be an appreciable portion of human and feline diets, a feeding study was conducted with cats fed exclusively bluefish for 86 days with determination of tissue concentrations of PCBs. The concentrations of PCBs in brain, liver, and fat were significantly higher (p = 0.01) in the fish-fed cats than in the control group using the Wilcoxon rank sum test. The highest PCB levels were in fat, the median concentrations being 48 and 0.61 ppm (dry weight) in the fish-fed and control cats, respectively. The significance of the results is discussed.

Toxicity test of xanthone from mangosteen on zebrafish embryos

NASA Astrophysics Data System (ADS)

Noordin, Muhammad Akram Mohd; Noor, Mahanem Mat; Kamaruddin, Wan Mohd Aizat Wan; Lazim, Azwan Mat; Fazry, Shazrul

2016-11-01

Xanthone is a chemical compound identified in mangosteen pericarp. A previous study showed that xanthone has anti-proliferating effect on cancer cells. In this study we investigate the toxicity level of xanthone in zebrafish embryo to for future reference on other animal model. We employed Fish Embryo Toxicity (FET) assay to determine the toxicity level of different concentrations of xanthone. Embryos were observed at 24, 48 and 72 hours post fertilization (hpf) under microscope at 4× magnification. The extract showed toxicity effect on embryo at concentrations of 250, 125 and 62.5 µg/mL. Concentrations at 15.63, 7.81 and 3.91 µg / mL of xanthone did not harm the embryos and showed 100% of survival.

Total particle, sulfate, and acidic aerosol emissions from kerosene space heaters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leaderer, B.P.; Boone, P.M.; Hammond, S.K.

1990-06-01

Chamber studies were conducted on four unvented kerosene space heaters to assess emissions of total particle, sulfate, and acidic aerosol. The heaters tested represented four burner designs currently in use by the public. Kerosene space heaters are a potential source of fine particles ({<=} 2.5-{mu}m diameter), sulfate, and acidic aerosol indoors. Fine particle concentrations in homes in which the heaters are used may be increased in excess of 20 {mu}g/m{sup 3} over background levels. Sulfate and acidic aerosol levels in such homes could exceed average and peak outdoor concentrations. Maltuned heaters could produce exceptionally high levels of all air contaminantsmore » measured.« less

Total particle, sulfate, and acidic aerosol emissions from kerosene space heaters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leaderer, B.P.; Boone, P.M.; Hammond, S.K.

1990-01-01

The article discusses chamber studies of four unvented kerosene space heaters to assess emissions of total particle, sulfate, and acidic aerosol. The heaters tested represented four burner designs currently in use by the public. Kerosene space heaters are a potential source of fine particles (= or < 2.5 micrometer diameter), sulfate, and acidic aerosol indoors. Fine particle concentrations in houses in which the heaters are used may be increased in excess of 20 micrograms/m3 over background levels. Sulfate and acidic aerosol levels in such houses could exceed average and peak outdoor concentrations. Maltuned heaters could produce exceptionally high levels ofmore » all air contaminants measured.« less

Proposed testing of concrete sealers.

DOT National Transportation Integrated Search

2017-07-04

Chlorides, in sufficient concentrations, will cause corrosion of steel reinforcement in bridge decks. Previous studies have shown that de-icing chemicals and practices used by the Kentucky Transportation Cabinet (KYTC) can result in problematic level...

PROUCL 4.0 SOFTWARE

EPA Science Inventory

Statistical inference, including both estimation and hypotheses testing approaches, is routinely used to: estimate environmental parameters of interest, such as exposure point concentration (EPC) terms, not-to-exceed values, and background level threshold values (BTVs) for contam...

Effect of Nonsurgical Periodontal Therapy on Serum Highly Sensitive Capsule Reactive Protein and Homocysteine Levels in Chronic Periodontitis: A Pilot Study

PubMed Central

Mallapragada, Siddharth; Kasana, Jyoti; Agrawal, Pallavi

2017-01-01

Introduction: The aim of the present study was to assess the effect of nonsurgical periodontal therapy on circulating serum high-sensitivity capsule reactive protein (hs-CRP) and homocysteine (Hcy) levels in patients with chronic periodontitis. Materials and Methods: The study involved fifty participants. The test group included 25 systemically healthy controls (mean age 38.44 ± 3.27 years) with severe chronic periodontitis and the control group (n = 25) included age- and sex-matched systemically and periodontally healthy controls. Clinical parameters were recorded, intraoral periapical radiographs were taken, hematological tests and assessment of serum hs-CRP levels and Hcy levels were performed at baseline and 3 months after completion of nonsurgical periodontal therapy. Results: Mean serum hs-CRP and Hcy concentration in patients with chronic periodontitis were 3.37 ± 0.54 mg/L and 21.47 ± 7.93 μmol/L, respectively, and was significantly higher than the controls (1.68 ± 0.71 mg/L and 13.93 ± 8.30 μmol/L, respectively) (P < 0.05). Posttreatment, the mean serum hs-CRP and Hcy concentration reduced significantly in both test and control groups (P < 0.05). Conclusion: Chronic periodontitis leads to an increase in circulating levels of hs-CRP and Hcy in plasma and nonsurgical periodontal therapy decreases periodontal inflammation, which in turn reduces systemic inflammation and consequently decreases serum levels of hs-CRP and Hcy. PMID:28839416

Association between memory impairment and brain metabolite concentrations in North Korean refugees with posttraumatic stress disorder.

PubMed

Shin, Jung Eun; Choi, Chi-Hoon; Lee, Jong Min; Kwon, Jun Soo; Lee, So Hee; Kim, Hyun-Chung; Han, Na Young; Choi, Soo-Hee; Yoo, So Young

2017-01-01

Individuals with posttraumatic stress disorder (PTSD) had experiences of enormous psychological stress that can result in neurocognitive and neurochemical changes. To date, the causal relationship between them remains unclear. The present study is to investigate the association between neurocognitive characteristics and neural metabolite concentrations in North Korean refugees with PTSD. A total of 53 North Korean refugees with or without PTSD underwent neurocognitive function tests. For neural metabolite scanning, magnetic resonance spectroscopy of the hippocampus and anterior cingulate cortex (ACC) has been conducted. We assessed between-group differences in neurocognitive test scores and metabolite levels. Additionally, a multiple regression analysis was carried out to evaluate the association between neurocognitive function and metabolite levels in patients with PTSD. Memory function, but not other neurocognitive functions, was significantly lower in the PTSD group compared with the non-PTSD group. Hippocampal N-acetylaspartate (NAA) levels were not different between groups; however, NAA levels were significantly lower in the ACC of the PTSD group than the non-PTSD group (t = 2.424, p = 0.019). The multiple regression analysis showed a negative association between hippocampal NAA levels and delayed recall score on the auditory verbal learning test (β = -1.744, p = 0.011) in the non-PTSD group, but not in the PTSD group. We identified specific memory impairment and the role of NAA levels in PTSD. Our findings suggest that hippocampal NAA has a protective role in memory impairment and development of PTSD after exposure to traumatic events.

Treatment of hospital waste water by ozone technology

NASA Astrophysics Data System (ADS)

Indah Dianawati, Rina; Endah Wahyuningsih, Nur; Nur, Muhammad

2018-05-01

Conventional treatment hospital wastewater need high cost, large area, long time and the final result leaves a new waste known as sludge. Alternative to more efficient and new technologies for treated hospital wastewaters was ozonation. Ozonation is able to oxidized pollutant materials in wastewater. This research is to know the decrease of COD and TDS levels with ozone. Waste water samples used by dr. Adhyatma, MPH Hospitals Semarang. Kruskal-Wallis test for COD and TDS with variation of concentration p-value = 0,029 and 0,001 (p≤0,05) or there is significantly difference between COD and TDS with level of concentration but there were no different between levels of COD, and TDS with reactions time variations p-value = 0,735, and 0,870 (p≥0.05). Ozone efficiently reduction of COD and TDS at a concentration of 100 mg/liter, the lowest mean value at COD 17.47 mg/liter and TDS 409.75 mg/liter.

[Dynamics of LINE-1 Retrotransposon Methylation Levels in Circulating DNA from Lung Cancer Patients Undergoing Antitumor Therapy].

PubMed

Ponomaryova, A A; Cherdyntseva, N V; Bondar, A A; Dobrodeev, A Y; Zavyalov, A A; Tuzikov, S A; Vlassov, V V; Choinzonov, E L; Laktionov, P P; Rykova, E Y

2017-01-01

Malignant cell transformation is accompanied with abnormal DNA methylation, such as the hypermethylation of certain gene promoters and hypomethylation of retrotransposons. In particular, the hypomethylation of the human-specific family of LINE-1 retrotransposons was observed in lung cancer tissues. It is also known that the circulating DNA (cirDNA) of blood plasma and cell-surface-bound circulating DNA (csb-cirDNA) of cancer patients accumulate tumor-specific aberrantly methylated DNA fragments, which are currently considered to be valuable cancer markers. This work compares LINE-1 retrotransposon methylation patterns in cirDNA of 16 lung cancer patients before and after treatment. CirDNA was isolated from blood plasma, and csb-cirDNA fractions were obtained by successive elution with EDTA-containing phosphate buffered saline and trypsin. Concentrations of methylated LINE-1 region 1 copies (LINE-1-met) were assayed by real-time methylation-specific PCR. LINE-1 methylation levels were normalized to the concentration of LINE-1 region 2, which was independent of the methylation status (LINE-1-Ind). The concentrations of LINE-1-met and LINE-1-Ind in csb-cirDNA of lung cancer patients exhibited correlations before treatment (r = 0.54), after chemotherapy (r = 0.72), and after surgery (r = 0.83) (P < 0.05, Spearman rank test). In the total group of patients, the level of LINE-1 methylation (determined as the LINE-1-met/LINE-1-Ind ratio) was shown to increase significantly during the follow-up after chemotherapy (P < 0.05, paired t test) and after surgery compared to the level of methylation before treatment (P < 0.05, paired t test). The revealed association between the level of LINE-1 methylation and the effect of antitumor therapy was more pronounced in squamous cell lung cancer than in adenocarcinoma (P < 0.05 and P > 0.05, respectively). These results suggest a need for the further investigation of dynamic changes in levels of LINE-1 methylation depending on the antitumor therapy.

Residues of pharmaceutical products in recycled organic manure produced from sewage sludge and solid waste from livestock and relationship to their fermentation level.

PubMed

Motoyama, Miki; Nakagawa, Shuhei; Tanoue, Rumi; Sato, Yuri; Nomiyama, Kei; Shinohara, Ryota

2011-07-01

In recent years, sludge generated in sewage treatment plants (STPs) and solid waste from livestock being utilized is useful for circulation of nourishment in farmlands as recycled organic manure (ROM). In this study, we determined the residue levels and patterns of 12 pharmaceutical products generated by human activity in the ROMs produced from human waste sludge (HWS), sewage sludge (SS), cattle manure (CM), poultry manure (PM), swine manure (SM) and horse manure (HM). The kind and number of pharmaceutical products detected in ROMs were different. Fluoroquinolones (FQs) were detected at high levels in HWS and SS samples. In addition, the detection frequency and concentration levels of sulfonamides (SAs) in PM and SM were high. Moreover, high concentrations of chlortetracycline (CTC) were found in only SM. These differences reflect specific adherence adsorption of the pharmaceutical products to different livestock and humans. Moreover, it was found that the concentrations of pharmaceutical products and fermentation levels of ROMs had significant positive correlation (r=0.41, p=0.024). When the fermentation test of ROM was conducted in a rotary fermentor in a lab scale test, the residue levels of pharmaceutical products decreased effectively except carbamazepine (CBZ). The rates of decrease were in the case of tetracyclines (TCs): 85-92%, FQs: 81-100%, erythromycine: 67%, SAs: 79-95%, trimethoprim: 86% and CBZ: 37% by 30 d. Pharmaceutical products that can be decomposed by fermentation process at the lowest impact of residual antibiotic activities may therefore be considered as environmentally friendly medicines. Copyright © 2011 Elsevier Ltd. All rights reserved.

Association Between Neuromuscular Tests and Kumite Performance on The Brazilian Karate National Team

PubMed Central

Roschel, Hamilton; Batista, Mauro; Monteiro, Rodrigo; Bertuzzi, Romulo C.; Barroso, Renato; Loturco, Irineu; Ugrinowitsch, Carlos; Tricoli, Valmor; Franchini, Emerson

2009-01-01

The aim of this study was to verify the relationship of strength and power with performance on an international level karate team during official kumite simulations. Fourteen male black belt karate athletes were submitted to anthropometric data collection and then performed the following tests on two different days: vertical jump test, bench press and squat maximum dynamic strength (1RM) tests. We also tested power production for both exercises at 30 and 60%1RM and performed a kumite match simulation. Blood samples were obtained at rest and immediately after the kumite matches to measure blood lactate concentration. Karate players were separated by performance (winners vs. defeated) on the kumite matches. We found no significant differences between winners and defeated for strength, vertical jump height, anthropometric data and blood lactate concentration. Interestingly, winners were more powerful in the bench press and squat exercises at 30% 1RM. Maximum strength was correlated with absolute (30% 1RM r = 0.92; 60% 1RM r = 0.63) and relative power (30% 1RM r = 0.74; 60% 1RM r = 0.11, p > 0.05) for the bench press exercise. We concluded that international level karate players’ kumite match performance are influenced by higher levels of upper and lower limbs power production. Key Points Muscle power at low workloads seems to be a reasonable predictor of karate performance. There are differences in neuromuscular characteristics between winners and defeated karate players among an international level karate team. Karate players rely more on muscle power, rather than on muscle strength. PMID:24474882

Estradiol concentrations and working memory performance in women of reproductive age.

PubMed

Hampson, Elizabeth; Morley, Erin E

2013-12-01

Estrogen has been proposed to exert a regulatory influence on the working memory system via actions in the female prefrontal cortex. Tests of this hypothesis have been limited almost exclusively to postmenopausal women and pharmacological interventions. We explored whether estradiol discernibly influences working memory within the natural range of variation in concentrations characteristic of the menstrual cycle. The performance of healthy women (n=39) not using hormonal contraceptives, and a control group of age- and education-matched men (n=31), was compared on a spatial working memory task. Cognitive testing was done blind to ovarian status. Women were retrospectively classified into low- or high-estradiol groups based on the results of radioimmunoassays of saliva collected immediately before and after the cognitive testing. Women with higher levels of circulating estradiol made significantly fewer errors on the working memory task than women tested under low estradiol. Pearson's correlations showed that the level of salivary estradiol but not progesterone was correlated inversely with the number of working memory errors produced. Women tested at high levels of circulating estradiol tended to be more accurate than men. Superior performance by the high estradiol group was seen on the working memory task but not on two control tasks, indicating selectivity of the effects. Consistent with previous studies of postmenopausal women, higher levels of circulating estradiol were associated with better working memory performance. These results add further support to the hypothesis that the working memory system is modulated by estradiol in women, and show that the effects can be observed under non-pharmacological conditions. Copyright © 2013 Elsevier Ltd. All rights reserved.

Increased IgE serum levels are unrelated to allergic and parasitic diseases in patients with juvenile systemic lupus erythematosus.

PubMed

Liphaus, Bernadete L; Jesus, Adriana A; Silva, Clovis A; Coutinho, Antonio; Carneiro-Sampaio, Magda

2012-11-01

The aim of this study was to assess the IgE serum levels in juvenile systemic lupus erythematosus patients and to evaluate possible associations with clinical and laboratory features, disease activity and tissue damage. The IgE serum concentrations in 69 consecutive juvenile systemic lupus erythematosus patients were determined by nephelometry. IgG, IgM and IgA concentrations were measured by immunoturbidimetry. All patients were negative for intestinal parasites. Statistical analysis methods included the Mann-Whitney, chi-square and Fisher's exact tests, as well as the Spearman rank correlation coefficient. Increased IgE concentrations above 100 IU/mL were observed in 31/69 (45%) juvenile systemic lupus erythematosus patients. The mean IgE concentration was 442.0 ± 163.4 IU/ml (range 3.5-9936.0 IU/ml). Fifteen of the 69 patients had atopic disease, nine patients had severe sepsis and 56 patients presented with nephritis. The mean IgE level in 54 juvenile systemic lupus erythematosus patients without atopic manifestations was 271.6 ± 699.5 IU/ml, and only nine of the 31 (29%) patients with high IgE levels had atopic disease. The IgE levels did not statistically differ with respect to the presence of atopic disease, severe sepsis, nephritis, disease activity, or tissue damage. Interestingly, IgE concentrations were inversely correlated with C4 levels (r = -0.25, p = 0.03) and with the SLICC/ACR-DI score (r = -0.34, p = 0.005). The IgE concentration was also found to be directly correlated with IgA levels (r = 0.52, p = 0.03). The present study demonstrated for the first time that juvenile systemic lupus erythematosus patients have increased IgE serum levels. This increase in IgE levels was not related to allergic or parasitic diseases. Our results are in line with the hypothesis that high IgE levels can be considered a marker of immune dysregulation.

Effect of the lipid regulator Gemfibrozil in the Cladocera Daphnia magna at different temperatures.

PubMed

Salesa, Beatriz; Ferrando, María D; Villarroel, María J; Sancho, Encarna

2017-02-23

In the present study, an ecotoxicological approach to the evaluation of Gemfibrozil (GEM) as an emerging organic pollutant was done. In order to assess its toxicity, tests were conducted using the cladocera Daphnia magna. Experiments were carried out at 22°C and 28°C. EC 50 , feeding behavior, and chronic toxicity tests (21 days) were evaluated in D. magna exposed to GEM as well as cholesterol levels at 21-day chronic exposure. D. magna GEM EC 50 values (24 h) in our experimental conditions were 148.75 and 116.24 mg L -1 at 22°C and 28°C, respectively. Test concentrations of 0.1, 0.5, 1.0, 5.0 and 7.5 mg L -1 were selected for subacute and chronic experiments. Subacute short-term test (feeding study) was assessed after exposure to the toxicant. Filtration and ingestion rates of D. magna exposed animals did not show any significant difference (P > 0.05) with respect to control daphniids neither at 22°C nor at 28°C. Therefore, GEM test concentrations used in the present study did not reduce feeding behavior in D. magna. Temperature increased from 22°C to 28°C, which resulted in a decrease of the daphniids reproductive parameters such as brood size and number of young per female. Other parameters as longevity were not affected. The GEM concentrations used in the chronic test with D. magna did not affect daphniids longevity but some reproductive parameters as number of young per female or brood size were affected. Finally, a significant decreased in cholesterol levels was found in those animals exposed to the highest toxicant concentrations. More studies must be done to determine the possible implications of GEM in aquatic fauna and to derive its possible effects on the environment.

Protective Effect of Boric Acid on Oxidative DNA Damage In Chinese Hamster Lung Fibroblast V79 Cell Lines

PubMed Central

Yılmaz, Sezen; Ustundag, Aylin; Cemiloglu Ulker, Ozge; Duydu, Yalcın

2016-01-01

Objective Many studies have been published on the antioxidative effects of boric acid (BA) and sodium borates in in vitro studies. However, the boron (B) concentrations tested in these in vitro studies have not been selected by taking into account the realistic blood B concentrations in humans due to the lack of comprehensive epidemiological studies. The recently published epidemiological studies on B exposure conducted in China and Turkey provided blood B concentrations for both humans in daily life and workers under extreme exposure conditions in occupational setting. The results of these studies have made it possible to test antioxidative effects of BA in in vitro studies within the concentra- tion range relevant to humans. The aim of this study was to investigate the protective ef- fects of BA against oxidative DNA damage in V79 (Chinese hamster lung fibroblast) cells. The concentrations of BA tested for its protective effect was selected by taking the blood B concentrations into account reported in previously published epidemiological studies. Therefore, the concentrations of BA tested in this study represent the exposure levels for humans in both daily life and occupational settings. Materials and Methods In this experimental study, comet assay and neutral red uptake (NRU) assay methods were used to determinacy to toxicity and genotoxicity of BA and hydrogen peroxide (H2O2). Results The results of the NRU assay showed that BA was not cytotoxic within the tested concentrations (3, 10, 30, 100 and 200 µM). These non-cytotoxic concentrations were used for comet assay. BA pre-treatment significantly reduced (P<0.05, one-way ANOVA) the DNA damaging capacity of H2O2 at each tested BA concentrations in V79 cells. Conclusion Consequently, pre-incubation of V79 cells with BA has significantly reduced the H2O2-induced oxidative DNA damage in V79 cells. The protective effect of BA against oxidative DNA damage in V79 cells at 5, 10, 50, 100 and 200 μM (54, 108, 540, 1080, and 2161 ng/ml B equivalents) concentrations was proved in this in vitro study. PMID:26862534

Protective Effect of Boric Acid on Oxidative DNA Damage In Chinese Hamster Lung Fibroblast V79 Cell Lines.

PubMed

Yılmaz, Sezen; Ustundag, Aylin; Cemiloglu Ulker, Ozge; Duydu, Yalcın

2016-01-01

Many studies have been published on the antioxidative effects of boric acid (BA) and sodium borates in in vitro studies. However, the boron (B) concentrations tested in these in vitro studies have not been selected by taking into account the realistic blood B concentrations in humans due to the lack of comprehensive epidemiological studies. The recently published epidemiological studies on B exposure conducted in China and Turkey provided blood B concentrations for both humans in daily life and workers under extreme exposure conditions in occupational setting. The results of these studies have made it possible to test antioxidative effects of BA in in vitro studies within the concentra- tion range relevant to humans. The aim of this study was to investigate the protective ef- fects of BA against oxidative DNA damage in V79 (Chinese hamster lung fibroblast) cells. The concentrations of BA tested for its protective effect was selected by taking the blood B concentrations into account reported in previously published epidemiological studies. Therefore, the concentrations of BA tested in this study represent the exposure levels for humans in both daily life and occupational settings. In this experimental study, comet assay and neutral red uptake (NRU) assay methods were used to determinacy to toxicity and genotoxicity of BA and hydrogen peroxide (H2O2). The results of the NRU assay showed that BA was not cytotoxic within the tested concentrations (3, 10, 30, 100 and 200 µM). These non-cytotoxic concentrations were used for comet assay. BA pre-treatment significantly reduced (P<0.05, one-way ANOVA) the DNA damaging capacity of H2O2 at each tested BA concentrations in V79 cells. Consequently, pre-incubation of V79 cells with BA has significantly reduced the H2O2-induced oxidative DNA damage in V79 cells. The protective effect of BA against oxidative DNA damage in V79 cells at 5, 10, 50, 100 and 200 μM (54, 108, 540, 1080, and 2161 ng/ml B equivalents) concentrations was proved in this in vitro study.

Better functional mobility in community-dwelling elderly is related to D-hormone serum levels and to daily calcium intake.

PubMed

Dukas, L; Staehelin, H B; Schacht, E; Bischoff, H A

2005-01-01

The influence of calcitropic hormones on functional mobility has been studied in vitamin D (calcidiol) deficient elderly or elderly with a history of falls, however, data in community-dwelling independent vitamin D replete elderly are missing. We therefore assessed in an observational survey the association of calcidiol (25(OH)D3) and calcitriol (D-hormone / 1,25(OH)2D3) status as well as of daily calcium intake on functional mobility in older subjects We evaluated 192 women and 188 men, aged superior 70 years and living independently. Average Timed-up and go test (TUG-test) in seconds was taken as measure of functional mobility. Calcidiol and D-hormone serum concentrations and daily calcium intake were studied in multivariate controlled linear regression models with TUG-test performance as the dependent variable and/or as dichotomous variables (deficient vs. non-deficient, above vs. below the median, respectively). Subjects with low D-hormone serum concentrations took significantly more time to perform the TUG-test (low = 7.70s +/- 2.52 SD ; high = 6.70s +/- 1.29 SD; p = 0.004). In the linear multivariate controlled regression model increased D-hormone serum concentrations predicted better TUG-test performance (estimate -0.0007, p = 0.044). Participants with a calcium intake of > or =512 mg/day were significantly faster to perform the TUG-test than participants with a daily calcium intake of <512 mg/day (estimate:-0.43, p = 0.007). Other significant predictors of better TUG-test performance in both models were: male gender, less comorbid conditions, younger age, lower BMI, iPTH serum levels and creatinine clearance. Calcidiol serum levels were not associated with TUG-test performance. Higher D-hormone status and a calcium intake of > or =512 mg/day in community-dwelling independent older persons are significant determinants of better functional mobility. Therefore, to ensure optimal functional mobility, the care of older persons should address correction of D-hormone deficiency and increasing daily calcium intake.

Temporal changes in water quality at a childhood leukemia cluster.

PubMed

Seiler, Ralph L

2004-01-01

Since 1997, 15 cases of acute lymphocytic leukemia and one case of acute myelocytic leukemia have been diagnosed in children and teenagers who live, or have lived, in an area centered on the town of Fallon, Nevada. The expected rate for the population is about one case every five years. In 2001, 99 domestic and municipal wells and one industrial well were sampled in the Fallon area. Twenty-nine of these wells had been sampled previously in 1989. Statistical comparison of concentrations of major ions and trace elements in those 29 wells between 1989 and 2001 using the nonparametric Wilcoxon signed-rank test indicate water quality did not substantially change over that period; however, short-term changes may have occurred that were not detected. Volatile organic compounds were seldom detected in ground water samples and those that are regulated were consistently found at concentrations less than the maximum contaminant level (MCL). The MCL for gross-alpha radioactivity and arsenic, radon, and uranium concentrations were commonly exceeded, and sometimes were greatly exceeded. Statistical comparisons using the nonparametric Wilcoxon rank-sum test indicate gross-alpha and -beta radioactivity, arsenic, uranium, and radon concentrations in wells used by families having a child with leukemia did not statistically differ from the remainder of the domestic wells sampled during this investigation. Isotopic measurements indicate the uranium was natural and not the result of a 1963 underground nuclear bomb test near Fallon. In arid and semiarid areas where trace-element concentrations can greatly exceed the MCL, household reverse-osmosis units may not reduce their concentrations to safe levels. In parts of the world where radon concentrations are high, water consumed first thing in the morning may be appreciably more radioactive than water consumed a few minutes later after the pressure tank has been emptied because secular equilibrium between radon and its immediate daughter progeny is attained in pressure tanks overnight.

Effects of processed oil shale on the element content of Atriplex cancescens

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, B.M.

1982-01-01

Samples of four-wing saltbush were collected from the Colorado State University Intensive Oil Shale Revegetation Study Site test plots in the Piceance basin, Colorado. The test plots were constructed to evaluate the effects of processed oil shale geochemistry on plant growth using various thicknesses of soil cover over the processed shale and/or over a gravel barrier between the shale and soil. Generally, the thicker the soil cover, the less the influence of the shale geochemistry on the element concentrations in the plants. Concentrations of 20 elements were larger in the ash of four-wing saltbush growing on the plot with themore » gravel barrier (between the soil and processed shale) when compared to the sample from the control plot. A greater water content in the soil in this plot has been reported, and the interaction between the increased, percolating water and shale may have increased the availability of these elements for plant uptake. Concentrations of boron, copper, fluorine, lithium, molybdenum, selenium, silicon, and zinc were larger in the samples grown over processed shale, compared to those from the control plot, and concentrations for barium, calcium, lanthanum, niobium, phosphorus, and strontium were smaller. Concentrations for arsenic, boron, fluorine, molybdenum, and selenium - considered to be potential toxic contaminants - were similar to results reported in the literature for vegetation from the test plots. The copper-to-molybdenum ratios in three of the four samples of four-wing saltbush growing over the processed shale were below the ratio of 2:1, which is judged detrimental to ruminants, particularly cattle. Boron concentrations averaged 140 ppM, well above the phytotoxicity level for most plant species. Arsenic, fluorine, and selenium concentrations were below toxic levels, and thus should not present any problem for revegetation or forage use at this time.« less

Temporal changes in water quality at a childhood leukemia cluster

USGS Publications Warehouse

Seiler, R.L.

2004-01-01

Since 1997, 15 cases of acute lymphocytic leukemia and one case of acute myelocytic leukemia have been diagnosed in children and teenagers who live, or have lived, in an area centered on the town of Fallon, Nevada. The expected rate for the population is about one case every five years. In 2001, 99 domestic and municipal wells and one industrial well were sampled in the Fallon area. Twenty-nine of these wells had been sampled previously in 1989. Statistical comparison of concentrations of major ions and trace elements in those 29 wells between 1989 and 2001 using the nonparametric Wilcoxon signed-rank test indicate water quality did not substantially change over that period; however, short-term changes may have occurred that were not detected. Volatile organic compounds were seldom detected in ground water samples and those that are regulated were consistently found at concentrations less than the maximum contaminant level (MCL). The MCL for gross-alpha radioactivity and arsenic, radon, and uranium concentrations were commonly exceeded, and sometimes were greatly exceeded. Statistical comparisons using the nonparametric Wilcoxon rank-sum test indicate gross-alpha and -beta radioactivity, arsenic, uranium, and radon concentrations in wells used by families having a child with leukemia did not statistically differ from the remainder of the domestic wells sampled during this investigation. Isotopic measurements indicate the uranium was natural and not the result of a 1963 underground nuclear bomb test near Fallon. In arid and semiarid areas where trace-element concentrations can greatly exceed the MCL, household reverse-osmosis units may not reduce their concentrations to safe levels. In parts of the world where radon concentrations are high, water consumed first thing in the morning may be appreciably more radioactive than water consumed a few minutes later after the pressure tank has been emptied because secular equilibrium between radon and its immediate daughter progeny is attained in pressure tanks overnight.

Polarization sensitive optical low-coherence reflectometry for blood glucose monitoring in human subjects

NASA Astrophysics Data System (ADS)

Solanki, Jitendra; Choudhary, Om Prakash; Sen, P.; Andrews, J. T.

2013-07-01

A device based on polarization sensitive optical low-coherence reflectometry is developed to monitor blood glucose levels in human subjects. The device was initially tested with tissue phantom. The measurements with human subjects for various glucose concentration levels are found to be linearly dependent on the ellipticity obtainable from the home-made phase-sensitive optical low-coherence reflectometry device. The linearity obtained between glucose concentration and ellipticity are explained with theoretical calculations using Mie theory. A comparison of results with standard clinical methods establishes the utility of the present device for non-invasive glucose monitoring.

Technology development of fabrication techniques for advanced solar dynamic concentrators

NASA Technical Reports Server (NTRS)

Richter, Scott W.

1991-01-01

The objective of the advanced concentrator program is to develop the technology that will lead to lightweight, highly reflective, accurate, scaleable, and long lived space solar dynamic concentrators. The advanced concentrator program encompasses new and innovative concepts, fabrication techniques, materials selection, and simulated space environmental testing. Fabrication techniques include methods of fabricating the substrates and coating substrate surfaces to produce high quality optical surfaces, acceptable for further coating with vapor deposited optical films. The selected materials to obtain a high quality optical surface include microsheet glass and Eccocoat EP-3 epoxy, with DC-93-500 selected as a candidate silicone adhesive and levelizing layer. The following procedures are defined: cutting, cleaning, forming, and bonding microsheet glass. Procedures are also defined for surface cleaning, and EP-3 epoxy application. The results and analyses from atomic oxygen and thermal cycling tests are used to determine the effects of orbital conditions in a space environment.

Neurobehavioral changes in response to alterations in gene expression profiles in the brains of mice exposed to low and high levels of mercury vapor during postnatal development.

PubMed

Yoshida, Minoru; Honda, Akiko; Watanabe, Chiho; Satoh, Masahiko; Yasutake, Akira

2014-08-01

This study examined the relationship between neurobehavioral changes and alterations in gene expression profiles in the brains of mice exposed to different levels of Hg(0) during postnatal development. Neonatal mice were repeatedly exposed to mercury vapor (Hg(0)) at a concentration of 0.057 mg/m(3) (low level), which was close to the current threshold value (TLV), and 0.197 mg/m(3) (high level) for 24 hr until the 20(th) day postpartum. Behavioral responses were evaluated based on changes in locomotor activity in the open field test (OPF), learning ability in the passive avoidance response test (PA), and spatial learning ability in the Morris water maze (MM) at 12 weeks of age. No significant differences were observed in the three behavioral measurements between mice exposed to the low level of Hg(0) and control mice. On the other hand, total locomotive activity in mice exposed to the high level of Hg(0) was significantly decreased and central locomotion was reduced in the OPF task. Mercury concentrations were approximately 0.4 μg/g and 1.9 μg/g in the brains of mice exposed to the low and high levels of Hg(0), respectively. Genomic analysis revealed that the expression of 2 genes was up-regulated and 18 genes was down-regulated in the low-level exposure group, while the expression of 3 genes was up-regulated and 70 genes was down-regulated in the high-level exposure group. Similar alterations in the expression of seven genes, six down-regulated genes and one up-regulated gene, were observed in both groups. The results indicate that an increase in the number of altered genes in the brain may be involved in the emergence of neurobehavioral effects, which may be associated with the concentration of mercury in the brain. Moreover, some of the commonly altered genes following exposure to both concentrations of Hg(0) with and without neurobehavioral effects may be candidates as sensitive biomarker genes for assessing behavioral effects in the early stages of development.

Copper-complexing ligands produced by an intact estuarine microbial community in response to copper stress.

NASA Astrophysics Data System (ADS)

Bingham, J.; Dryden, C.; Gordon, A.

2002-12-01

Copper is both an important nutrient and a pollutant in the marine environment. By studying the interactions between microorganisms and copper in the Elizabeth River (VA), home to a major Naval Base, we field tested the hypothesis that picoplankton and/or bacterioplankton produce strong, copper-complexing ligands in response to elevated copper concentrations. A simple light/ dark test was used to distinguish between heterotrophic and phototrophic ligand production. Samples were bottled and moored, submerged one meter, for a week. Direct counts using DAPI stain and epiflourescence were conducted to find concentrations of picoplankton and bacterioplankton. Using cathodic stripping voltammetry, we found the total copper concentrations, and then from a titration of the ligands by copper, the ligand concentrations and conditional stability constants were obtained. The Elizabeth River naturally had between 10-20 nM total dissolved copper concentrations. However when copper complexation was considered we found that the levels of bio-available Cu(II) ions were much lower. In fact in the natural samples the levels were not high enough to affect the relative reproductive rates of several microorganisms. Naturally there was a 50 nM "buffer zone" of ligand to total dissolved copper concentration. Furthermore, when stressed with excess copper, healthy picoplankton produced enough ligand to alleviate toxicity, and rebuild the buffer zone. However bacterioplankton only produced enough ligand so that they were no longer affected. Therefore, intact estuarine communities regulate copper bioavailability and toxicity with ligand production.

Accumulation of heavy metals in soil and their transfer to leafy vegetables in the region of Dhaka Aricha Highway, Savar, Bangladesh.

PubMed

Aktaruzzaman, M; Fakhruddin, A N M; Chowdhury, M A Z; Fardous, Z; Alam, M K

2013-04-01

Accumulation of heavy metals in environmental matrices is a potential risk to living system due to their uptake by plants and subsequent introduction into the food chain. A study was conducted to investigate the heavy metals concentration in soils and leafy vegetables samples along the Dhaka Aricha Road to assess their potential ecological risk. Heavy metals concentration was analyzed by Atomic Absorption Spectroscopy. Concentrations ofallthetestedheavy metals except Cd in soil samples were below the permissible level. The mean concentration of Cd was found 3.99 +/- 1.85 mg kg(-1). Concentrations of all the tested heavy metals except Cd and Cr in vegetables samples were lower than recommended level. Mean concentration of Cd and Cr were found 1.00 +/- 0.68 mg kg(-1) and 2.32 +/- 0.84 mg kg(-1), respectively. Based on the Potential Ecological Risk Index, Cd posed very high risk to the local ecosystem due to its higher Risk Factor, > 320 and based on Transfer Factor of Pb and Cd were found higher accumulator among the tested metals. The results of present study revealed that the bioconcentration of heavy metals along the Dhaka Aricha Road posed high risk to the ecosystem. Considering the Transfer Factor of Cd and Pb it can be suggested that plants and leafy vegetables grow in the soil near Dhaka Aricha Road should not be used as food or feed.

Barrage fishponds: Reduction of pesticide concentration peaks and associated risk of adverse ecological effects in headwater streams.

PubMed

Gaillard, Juliette; Thomas, Marielle; Iuretig, Alain; Pallez, Christelle; Feidt, Cyril; Dauchy, Xavier; Banas, Damien

2016-03-15

Constructed wetlands have been suggested as pesticide risk mitigation measures. Yet, in many agricultural areas, ponds or shallow lakes are already present and may contribute to the control of non-point source contamination by pesticides. In order to test this hypothesis, we investigated the influence of extensively managed barrage fishponds (n = 3) on the dissolved concentrations of 100 pesticides in headwater streams over the course of a year. Among the 100 pesticides, 50 different substances were detected upstream and 48 downstream. Highest measured concentration upstream was 26.5 μg/L (2-methyl-4-chlorophenoxyacetic acid, MCPA) and 5.19 μg/L (isoproturon) downstream. Fishponds were found to reduce peak exposure levels as high pesticide concentrations (defined here as ≥ 1 μg/L) generally decreased by more than 90% between upstream and downstream sampling sites. The measured concentrations in the investigated streams were compared to laboratory toxicity data for standard test organisms (algae, invertebrates and fish) using the toxic unit approach. When considering the threshold levels set by the European Union within the first tier risk assessment procedure for pesticide registration (commission regulation (EU) N° 546/2011), regulatory threshold exceedances were observed for 22 pesticides upstream from fishponds and for 9 pesticides downstream. Therefore, the investigated barrage fishponds contributed to the reduction of pesticide peak concentrations and potential risk of adverse effects for downstream ecosystems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Differential effects of mental stress on plasma homovanillic acid in schizophrenia and normal controls.

PubMed

Sumiyoshi, T; Saitoh, O; Yotsutsuji, T; Itoh, H; Kurokawa, K; Kurachi, M

1999-04-01

We previously reported that mental stress by Kraepelin's arithmetic test decreases plasma homovanillic acid (pHVA) levels in psychiatrically normal healthy human subjects. The present study was undertaken to determine whether this pattern of changes in pHVA concentrations resulting from mental stress is altered in patients with schizophrenia. Fourteen male patients with schizophrenia including those under ongoing neuroleptic treatment and 14 normal male volunteers participated in the study. Following overnight fast and restricted physical activity, the subjects performed Kraepelin's arithmetic test for 30 minutes. Plasma samples were collected immediately before and after the test for measurement of pHVA levels. A significant diagnosis by Kraepelin's test effect was observed due to a decrease in pHVA levels by the Kraepelin test in control subjects but not in patients with schizophrenia. Changes in pHVA levels during the Kraepelin test positively correlated with pre-test pHVA levels in control subjects, while this correlation was not observed in patients with schizophrenia. These results may be further support for the presence of a dopamine-dependent restitutive system in the brain. The absence of response of pHVA levels to mental stress in patients with schizophrenia may indicate that the dopamine restitutive system in these patients is disrupted or already down-regulated, as previously predicted.

Variation in Nicotine Consumption in Inbred Mice Is Not Linked to Orosensory Ability

PubMed Central

Glatt, A. Rebecca; Denton, Kelley

2009-01-01

Genetic studies of nicotine addiction in mice have utilized the oral self-administration model. However, it is unclear if strain differences in nicotine consumption are influenced by variation in bitter taste sensitivity. We measured both nicotine consumption and nicotine brief-access licking behavior in several commonly used inbred strains of mice that were previously shown to differ in nicotine consumption. A/J (A), C57BL/6J (B6), and DBA/2J (D2) mice were given a 2-bottle choice test with a single concentration of nicotine (75 μg/ml; nicotine vs. water). Mice of these strains were also tested with a range of nicotine concentrations (5–400 μg/ml) using a brief-access test, which measures orosensory response and minimizes postingestive effects. Although B6 mice consumed more 75-μg/ml nicotine than A or D2 mice in the 2-bottle test, these strains did not differ in level of aversion to nicotine when tested with the brief-access procedure. Strain differences in orosensory response to nicotine were not found; yet, differences emerged during the 2-bottle tests. This study provides evidence that variation in intake level of nicotine is likely not due to differences in taste or trigeminal sensitivity but likely due to postingestive factors. PMID:18775876

Ecologically-based clean-up criteria for nitroaromatic explosives using toxicity test results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duh, D.; Roberts, B.; Buzgo, S.

1995-12-31

A former trinitrotoluene (TNT) production and storage facility was the focus of a Remedial Investigation (RI). Contaminants identified during the RI included 2,4-dinitrotoluene (DNT), 2,6-DNT, and 2,4,6-TNT, PCBs, arsenic, lead and chromium. The Conceptual Site Model determined there to be several complete exposure pathways. One of these identified a route by which soil invertebrate communities could be affected through dermal contact and ingestion of soil contaminants. Maintenance of the soil invertebrate community was chosen as the assessment endpoints for this pathway in the Ecological Risk Assessment. The corresponding measurement endpoint was survival of earthworms in 14-day toxicity tests in whichmore » they were exposed to site soils. Seven surficial soil samples were collected from Areas of Concern. Each sample was evaluated for acute toxicity to earthworms using standard USEPA protocols. Chemical concentrations were also measured. An artificial soil was used as the control and diluent to establish the Lethal Concentration (LC{sub 50}) of the test soils to earthworms. From the toxicity test results and the corresponding chemical analysis, a matrix of toxicity and contaminant levels was developed. This table was used to determine a concentration of each contaminant at which no acute lethality would be expected. Lower bounds to the chemical specific LC{sub 50} values were determined and, based on sample-specific toxicity units, appropriate LC{sub 50} values were derived (333 mg/kg 2,4-DNT, 182 mg/kg 2,6-DNT, and 1960 mg/kg 2,4,6TNT). Extrapolation of this level to a chronic No Observable Adverse Effect Level (NOAEL) provided a means of proposing site-specific ecologically based clean-up criteria for the constituents of concern which would be protective of the chosen assessment endpoint.« less

Ultra-accelerated natural sunlight exposure testing

DOEpatents

Jorgensen, Gary J.; Bingham, Carl; Goggin, Rita; Lewandowski, Allan A.; Netter, Judy C.

2000-06-13

Process and apparatus for providing ultra accelerated natural sunlight exposure testing of samples under controlled weathering without introducing unrealistic failure mechanisms in exposed materials and without breaking reciprocity relationships between flux exposure levels and cumulative dose that includes multiple concurrent levels of temperature and relative humidity at high levels of natural sunlight comprising: a) concentrating solar flux uniformly; b) directing the controlled uniform sunlight onto sample materials in a chamber enclosing multiple concurrent levels of temperature and relative humidity to allow the sample materials to be subjected to accelerated irradiance exposure factors for a sufficient period of time in days to provide a corresponding time of about at least a years worth of representative weathering of the sample materials.

A new method for early assessment of effects of exposing two non-target crustacean species, Asellus aquaticus and Gammarus fossarum, to pesticides, a laboratory study.

PubMed

Lukancic, Simon; Zibrat, Uros; Mezek, Tadej; Jerebic, Andreja; Simcic, Tatjana; Brancelj, Anton

2010-05-01

A reliable method is needed for assessing the condition of aquatic animals and their resistance to toxic pollutants. The physiological responses of two freshwater crustaceans, Asellus aquaticus and Gammarus fossarum, following in vitro exposure to two pesticides (atrazine and imidacloprid), were measured by a combination of electron transport system (ETS) activity and respiration (R). Short-term exposure concentrations were selected according to standard toxicity tests and ranged from 0.01 mg L(-1) to 10 mg L(-1). When pesticide concentration was greater than 1 mg l(- 1) (which is below the LC(50) [48 hours] determined for both species), A. aquaticus and G. fossarum responded to short-term exposure with elevated levels of R and/or lower levels of ETS activity. One hour exposure to concentrations of up to 10 mg L(-1) showed an effect in both test species. Laboratory tests confirmed that G. fossarum is more sensitive to short-term pesticide exposure than A. aquaticus. The combination of these two methods provides a useful and effective tool for assessing the general condition of aquatic animals. It also enables to determine toxic effects on freshwater biota of specific or combined pollutants. ETS/R ratio may be used as a quick predictor of effects on organisms exposed to pesticides and other stress factors such as changes in temperature, light, salinity, oxygen concentration and food.

Glucose concentration in the blood of intact and alloxan-treated mice after pretreatment with commercial preparations of Stevia rebaudiana (Bertoni).

PubMed

Raskovic, Aleksandar; Gavrilovic, Maja; Jakovljevic, Vida; Sabo, Jan

2004-01-01

The study was concerned with the effect of mice pretreatment with two commercial products of Stevia rebaudiana Bertoni on the blood glucose concentration. One group of mice was pretreated four days with 200 mg/kg of Stevita (Stevita Co, INC, Arlington Texas) (stevia) and the other with 20 mg/kg of Clear Steviosides liquid (Stevita Co, INC, Herbal supplement, Brazil) (stevioside), whereas the animals of control group received at the same time physiological solution. Blood glucose concentration was measured before pretreatment and four days after that. The changes in glucose level were provoked by glucose-tolerance test (500 mg/kg, p.o.) and subcutaneous injection of adrenaline (0.2 mg/kg). The same procedure of measuring blood glucose was applied on the mice with alloxan-induced diabetes mellitus (two doses of 100 mg/kg with a 24-hour interval). Blood glucose levels in mice pretreated with stevia and stevioside were lower compared with control (7.82:6.82:8.01). Also, a smaller increase in this parameter compared to control was registered with pretreated mice in the glucose-tolerance test, pretreatment with stevioside being again more effective (8.68:6.36:5.82). Pretreatment with stevioside caused no significant increase in blood glucose concentration after administering adrenaline, which was not the case with the animals pretreated with stevia and control. Pretreatment with stevia, and to a greater extent with stevioside, protected test animals from the toxic action of alloxan compared with controls.

Sampling hazelnuts for aflatoxin: uncertainty associated with sampling, sample preparation, and analysis.

PubMed

Ozay, Guner; Seyhan, Ferda; Yilmaz, Aysun; Whitaker, Thomas B; Slate, Andrew B; Giesbrecht, Francis

2006-01-01

The variability associated with the aflatoxin test procedure used to estimate aflatoxin levels in bulk shipments of hazelnuts was investigated. Sixteen 10 kg samples of shelled hazelnuts were taken from each of 20 lots that were suspected of aflatoxin contamination. The total variance associated with testing shelled hazelnuts was estimated and partitioned into sampling, sample preparation, and analytical variance components. Each variance component increased as aflatoxin concentration (either B1 or total) increased. With the use of regression analysis, mathematical expressions were developed to model the relationship between aflatoxin concentration and the total, sampling, sample preparation, and analytical variances. The expressions for these relationships were used to estimate the variance for any sample size, subsample size, and number of analyses for a specific aflatoxin concentration. The sampling, sample preparation, and analytical variances associated with estimating aflatoxin in a hazelnut lot at a total aflatoxin level of 10 ng/g and using a 10 kg sample, a 50 g subsample, dry comminution with a Robot Coupe mill, and a high-performance liquid chromatographic analytical method are 174.40, 0.74, and 0.27, respectively. The sampling, sample preparation, and analytical steps of the aflatoxin test procedure accounted for 99.4, 0.4, and 0.2% of the total variability, respectively.

Genotoxicity and toxicity assay of water sampled from a radium production industry storage cell territory by means of Allium-test.

PubMed

Evseeva, Tatiana I; Geras'kin, Stanislav A; Shuktomova, Ida I

2003-01-01

Water from natural reservoirs located near the radium production industry storage cell were analyzed using the anaphase-telophase chromosome aberration assay that was carried out on Allium schoenoprasum L. meristematic root tip cells. (262)Ra, (228)U, (232)Th, (210)Pb and (210)Po concentrations in all samples were found not to exceed the radioactivity concentration guides. The concentrations of 10 heavy metal ions were measured in water samples, but only Zn and Mn levels exceeded the maximum permissible concentration for the natural reservoirs. All water samples caused a significant increase of the chromosome aberration frequency as compared to control. The chromosome aberration spectrum analysis shows that the genotoxic effect was a result of chemical toxicity mainly. Two samples from the brook springhead were found to be toxic. The regression analysis results show that the mitotic index increased in parallel to Zn ion levels, and decreased with higher (238)U concentrations. The water samples genotoxicity positively correlated with the Zn concentration. The present work demonstrates that in order to achieve pollutant screening, it is not sufficient to determine the pollutants concentration only. Adequate conclusions on the risk due to environment contamination need to be based on the additional simultaneous use of toxicity and genotoxicity tests. When bioassays indicate some genotoxic and toxic effects, the determination of the chemical composition of the samples is then required. A combination of these two methods allows the identification of the elements that require constant biological monitoring. In the study reported here, those elements are Zn and (238)U.

Evaluation of Water-Chemistry and Water-Level Data at the Henderson Road Superfund Site, Upper Merion Township, Montgomery County, Pennsylvania, 1991-2008

USGS Publications Warehouse

Sloto, Ronald A.

2009-01-01

Several shutdown-rebound tests have been conducted at the Henderson Road Superfund Site, which has been on the U.S. Environmental Protection Agency's National Priorities List since 1984. For a given test, the extraction wells are turned off, and water samples are collected from selected monitor wells at regular intervals before and during cessation of pumping to monitor for changes in chemical concentrations. A long-term shutdown-rebound test began on July 17, 2006. In support of this test, the U.S. Geological Survey conducted this study to determine the effects of shutting down on-site extraction wells on concentrations of selected contaminants and water levels. Concentrations were compared to ARARs (applicable relevant and appropriate requirements), which were set as remediation goals in the Henderson Road Site Record of Decision. Water from 10 wells in and near the source area and to the north, northeast, and northwest of the source area sampled in 2008 exceeded the 5.52 ug/L (micrograms per liter) ARAR for benzene. The greatest changes in benzene concentration between pre-shutdown samples collected in July 2006 and samples collected in February and March 2008 (19 months after the shutdown) were for wells in and north of the source area; increases in benzene concentration ranged from 1.5 to 164 ug/L. Water from five wells in the source area and to the north and northwest of the source area sampled in 2008 exceeded the 60 ug/L ARAR for chlorobenzene. The greatest changes in chlorobenzene concentration between pre-shutdown samples collected in July 2006 and samples collected in February and March 2008 were for wells north of the source area; increases in chlorobenzene concentration ranged from 6.9 to 99 ug/L. The highest concentrations of chlorobenzene were near or outside the northern site boundary, indicating chlorobenzene may have moved north away from the source area; however, no monitor well clusters are on the northern side of the Pennsylvania Turnpike, which is about 190 feet north of the source area. A much larger area was affected by chlorobenzene than benzene. Chlorobenzene concentrations decreased in the source area and increased at and beyond the site boundary. Water from four wells in and northeast of the source area sampled in 2008 exceeded the 5.06 ug/L ARAR for 1,1-dichloroethane (1,1-DCA). Increases in 1,1-DCA concentration between pre-shutdown samples collected in July 2006 and samples collected in February 2008 ranged from 0.4 to 20 ug/L. Water from two wells in the source area sampled in 2008 exceeded the 175 ug/L ARAR for total xylene. The 1,1-DCA and xylene plumes appear to extend in an east-northeast direction from the source area. Large drawdowns in the Upper Merion Reservoir during droughts in 1998 and 2001 affected water levels in the Chester Valley and at the Henderson Road Site, except for well HR-17-170. After the drought of 2001, water levels in the Chester Valley showed a protracted recovery lasting from September 2001 until June 2005 (46 months). Water-level data were evaluated temporally for 1997-2008 and spatially for (1) June 16, 2003, when the extraction wells were pumping at the full rate prior to the start of the June 2003 shutdown test; (2) July 10, 2006, during the period of reduced pumping after the June 2003 shutdown test; and (3) February 25-29, 2008, when the extraction wells were not pumping. Except for well HR-5-195, wells were categorized as shallow, intermediate-depth, and deep wells. The potentiometric surface for shallow wells did not appear to be affected by pumping of the extraction wells. The general direction of ground-water flow was to the north. The potentiometric surface for intermediate-depth wells showed a cone of depression when the extraction wells were pumping at the full rate but did not show a cone of depression when the extraction wells were pumping at the reduced rate. The ground-water-flow direction was toward the north and northeast, similar to

40 CFR Appendix IV to Part 265 - Tests for Significance

Code of Federal Regulations, 2014 CFR

2014-07-01

... changes in the concentration or value of an indicator parameter in periodic ground-water samples when... then be compared to the value of the t-statistic found in a table for t-test of significance at the specified level of significance. A calculated value of t which exceeds the value of t found in the table...

40 CFR Appendix IV to Part 265 - Tests for Significance

Code of Federal Regulations, 2011 CFR

2011-07-01

... changes in the concentration or value of an indicator parameter in periodic ground-water samples when... then be compared to the value of the t-statistic found in a table for t-test of significance at the specified level of significance. A calculated value of t which exceeds the value of t found in the table...

40 CFR Appendix IV to Part 265 - Tests for Significance

Code of Federal Regulations, 2012 CFR

2012-07-01

... changes in the concentration or value of an indicator parameter in periodic ground-water samples when... then be compared to the value of the t-statistic found in a table for t-test of significance at the specified level of significance. A calculated value of t which exceeds the value of t found in the table...

40 CFR Appendix IV to Part 265 - Tests for Significance

Code of Federal Regulations, 2013 CFR

2013-07-01

... changes in the concentration or value of an indicator parameter in periodic ground-water samples when... then be compared to the value of the t-statistic found in a table for t-test of significance at the specified level of significance. A calculated value of t which exceeds the value of t found in the table...

76 FR 37838 - Petitions for Modification of Application of Existing Mandatory Safety Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-28

... may include periodic tests of methane levels and limits on the minimum methane concentrations that may...) Methane monitor(s) will be calibrated on the longwall, continuous mining machine, or cutting machine and... petitioner will test for methane with a hand-held methane detector at least every 10 minutes from the time...

The production and activity test of cellulases using bagasse substrate on Aspergillus niger isolated from Clove field, Kare, Madiun

NASA Astrophysics Data System (ADS)

Ardhi, Muh. Waskito; Sulistyarsi, Ani; Pujiati

2017-06-01

Aspergillus sp is a microorganism which has a high ability to produce cellulase enzymes. In producing Cellulase enzymes requires appropriate concentration and incubation time to obtain optimum enzyme activity. This study aimed to determine the effect of inoculum concentration and incubation time towards production and activity of cellulases from Aspergillus sp substrate bagasse. This research used experiments method; completely randomized design with 2 factorial repeated 2 times. The treatment study include differences inoculum (K) 5% (K1), 15% (K2) 25%, (K3) and incubation time (F) that is 3 days (F1), 6 days (F2), 9 days (F3), 12 days (F4). The data taken from the treatment are glucose reduction and protein levels of crude cellulase enzyme activity that use Nelson Somogyi and Biuret methods. Analysis of variance ANOVA data used two paths with significance level of 5% then continued with LSD test. The results showed that: Fhit>Ftab. Thus, there is effect of inoculum concentrations and incubation time toward activity of crude cellulases of Aspergillus sp. The highest glucose reduction of treatment is K3F4 (concentration of inoculum is 25% with 12 days incubation time) amount 12.834 g / ml and the highest protein content is K3F4 (concentration of inoculum is 25% with with 12 days incubation time) amount 0.740 g / ml.

A colorimetric probe based on desensitized ionene-stabilized gold nanoparticles for single-step test for sulfate ions.

PubMed

Arkhipova, Viktoriya V; Apyari, Vladimir V; Dmitrienko, Stanislava G

2015-03-15

Desensitized ionene-stabilized gold nanoparticles have been prepared and applied as a colorimetric probe for the single-step test for sulfate ions at the relatively high concentration level. The approach is based on aggregation of the nanoparticles leading to the change in absorption spectra and color of the solution. These nanoparticles are characterized by the decreased sensitivity due to both electrostatic and steric stabilization, which allows for simple, and rapid direct single-step determination of sulfate at the relatively high concentration level in real water samples without sample pretreatment or dilution. Influence of different factors (the time of interaction, pH, the concentrations of sulfate ions and the nanoparticles) on the aggregation and analytical performance of the procedure was investigated. The method allows for the determination of sulfate ions in the mass range of 0.2-0.4 mg with RSD of 5% from the sample volume of less than 2 mL. It has a sharp dependence of the colorimetric response on the concentration of sulfate, which makes it prospective for indicating deviations of the sulfate concentration regarding some declared value chosen within the above range. The time of the analysis is 2 min. The method was applied to the analysis of mineral water samples. Copyright © 2014 Elsevier B.V. All rights reserved.

Organ distribution of 13N following intravenous injection of [13N]ammonia into portacaval-shunted rats

PubMed Central

Cruz, Nancy F.; Dienel, Gerald A.; Patrick, Tricia A.; Cooper, Arthur J. L.

2016-01-01

Ammonia is neurotoxic, and chronic hyperammonemia is thought to be a major contributing factor to hepatic encephalopathy in patients with liver disease. Portacaval shunting of rats is used as an animal model to study the detrimental metabolic effects of elevated ammonia levels on body tissues, particularly brain and testes that are deleteriously targeted by high blood ammonia. In normal adult rats, the initial uptake of label (expressed as relative concentration) in these organs was relatively low following a bolus intravenous injection of [13N]ammonia compared with lungs, kidneys, liver, and some other organs. The objective of the present study was to determine the distribution of label following intravenous administration of [13N]ammonia among 14 organs in portacaval-shunted rats at 12 weeks after shunt construction. At an early time point (12 sec) following administration of [13N]ammonia the relative concentration of label was highest in lung with lower, but still appreciable relative concentrations in kidney and heart. Clearance of 13N from blood and kidney tended to be slower in portacaval-shunted rats versus normal rats during the 2–10 min interval after the injection. At later times post injection, brain and testes tended to have higher-than-normal 13N levels, whereas many other tissues had similar levels in both groups. Thus, reduced removal of ammonia from circulating blood by the liver diverts more ammonia to extrahepatic tissues, including brain and testes, and alters the nitrogen homeostasis in these tissues. These results emphasize the importance of treatment paradigms designed to reduce blood ammonia levels in patients with liver disease. PMID:27822667

Organ Distribution of 13N Following Intravenous Injection of [13N]Ammonia into Portacaval-Shunted Rats.

PubMed

Cruz, Nancy F; Dienel, Gerald A; Patrick, Patricia A; Cooper, Arthur J L

2017-06-01

Ammonia is neurotoxic, and chronic hyperammonemia is thought to be a major contributing factor to hepatic encephalopathy in patients with liver disease. Portacaval shunting of rats is used as an animal model to study the detrimental metabolic effects of elevated ammonia levels on body tissues, particularly brain and testes that are deleteriously targeted by high blood ammonia. In normal adult rats, the initial uptake of label (expressed as relative concentration) in these organs was relatively low following a bolus intravenous injection of [ 13 N]ammonia compared with lungs, kidneys, liver, and some other organs. The objective of the present study was to determine the distribution of label following intravenous administration of [ 13 N]ammonia among 14 organs in portacaval-shunted rats at 12 weeks after shunt construction. At an early time point (12 s) following administration of [ 13 N]ammonia the relative concentration of label was highest in lung with lower, but still appreciable relative concentrations in kidney and heart. Clearance of 13 N from blood and kidney tended to be slower in portacaval-shunted rats versus normal rats during the 2-10 min interval after the injection. At later times post injection, brain and testes tended to have higher-than-normal 13 N levels, whereas many other tissues had similar levels in both groups. Thus, reduced removal of ammonia from circulating blood by the liver diverts more ammonia to extrahepatic tissues, including brain and testes, and alters the nitrogen homeostasis in these tissues. These results emphasize the importance of treatment paradigms designed to reduce blood ammonia levels in patients with liver disease.

Quantitative detection of glucose level based on radiofrequency patch biosensor combined with volume-fixed structures.

PubMed

Qiang, Tian; Wang, Cong; Kim, Nam-Young

2017-12-15

A concept for characterizing a radiofrequency (RF) patch biosensor combined with volume-fixed structures is presented for timely monitoring of an individual's glucose levels based on frequency variation. Two types of patch biosensors-separately integrated with a backside slot (0.53μL) and a front-side tank (0.70μL) structure-were developed to achieve precise and efficient detection while excluding the effects of interference due to the liquidity, shape, and thickness of the tested glucose sample. A glucose test analyte at different concentrations (50-600mg/dL) was dropped into the volume-fixed structures. It fully interacted with the RF patch electromagnetic field, effectively and sensitively changing the resonance frequency and magnitude of the reflection coefficient. Measurement results based on the resonance frequency showed high sensitivity up to 1.13MHz and 1.97MHz per mg/dL, and low detection limits of 26.54mg/dL and 15.22mg/dL, for the two types of patch biosensors, respectively, as well as a short response time of less than 1s. Excellent reusability of the proposed biosensors was verified through three sets of measurements for each individual glucose sample. Regression analysis revealed a good linear correlation between glucose concentrations and the resonance frequency shift. Moreover, to facilitate a multi-parameter-sensitive detection of glucose, the magnitude of the reflection coefficient was also tested, and it showed a good linear correlation with the glucose concentration. Thus, the proposed approach can be adopted for distinguishing glucose solution levels, and it is a potential candidate for early-stage detection of glucose levels in diabetes patients. Copyright © 2017 Elsevier B.V. All rights reserved.

Dynamics of leaf gas exchange, xylem and phloem transport, water potential and carbohydrate concentration in a realistic 3-D model tree crown.

PubMed

Nikinmaa, Eero; Sievänen, Risto; Hölttä, Teemu

2014-09-01

Tree models simulate productivity using general gas exchange responses and structural relationships, but they rarely check whether leaf gas exchange and resulting water and assimilate transport and driving pressure gradients remain within acceptable physical boundaries. This study presents an implementation of the cohesion-tension theory of xylem transport and the Münch hypothesis of phloem transport in a realistic 3-D tree structure and assesses the gas exchange and transport dynamics. A mechanistic model of xylem and phloem transport was used, together with a tested leaf assimilation and transpiration model in a realistic tree architecture to simulate leaf gas exchange and water and carbohydrate transport within an 8-year-old Scots pine tree. The model solved the dynamics of the amounts of water and sucrose solute in the xylem, cambium and phloem using a fine-grained mesh with a system of coupled ordinary differential equations. The simulations predicted the observed patterns of pressure gradients and sugar concentration. Diurnal variation of environmental conditions influenced tree-level gradients in turgor pressure and sugar concentration, which are important drivers of carbon allocation. The results and between-shoot variation were sensitive to structural and functional parameters such as tree-level scaling of conduit size and phloem unloading. Linking whole-tree-level water and assimilate transport, gas exchange and sink activity opens a new avenue for plant studies, as features that are difficult to measure can be studied dynamically with the model. Tree-level responses to local and external conditions can be tested, thus making the approach described here a good test-bench for studies of whole-tree physiology.

Association of Mood Disorders with Serum Zinc Concentrations in Adolescent Female Students.

PubMed

Tahmasebi, Kobra; Amani, Reza; Nazari, Zahra; Ahmadi, Kambiz; Moazzen, Sara; Mostafavi, Seyed-Ali

2017-08-01

Among various factors influencing mood disorders, the impact of micronutrient deficiencies has attracted a great attention. Zinc deficiency is considered to play a crucial role in the onset and progression of mood disorders in different stages of life. The main objective of this study was to assess the correlation between serum zinc levels and mood disorders in high school female students. This cross-sectional study was conducted on a random sample of 100 representative high school female students. The participants completed 24-h food recall questionnaires to assess the daily zinc intakes. Serum zinc status was assessed using flame atomic absorption spectrometry, and zinc deficiency was defined accordingly. Mood disorders were estimated by calculating the sum of two test scores including Beck's depression inventory (BDI) and hospital anxiety depression scale (HADS) tests. General linear model (GLM) and Pearson's regression test were applied to show the correlation of serum zinc levels and mood disorder scores and the correlation between zinc serum levels and BDI scores, respectively. Dietary zinc intake was higher in subjects with normal zinc concentrations than that of zinc-deficient group (p = 0.001). Serum zinc levels were inversely correlated with BDI and HADS scores (p < 0.05). Each 10 μg/dL increment in serum zinc levels led to 0.3 and 0.01 decrease in depression and anxiety scores, respectively (p < 0.05). Serum zinc levels were inversely correlated with mood disorders including depression and anxiety in adolescent female students. Increasing serum levels of zinc in female students could improve their mood disorders.

Cadmium ion inhibition of quorum signalling in Chromobacterium violaceum.

PubMed

Thornhill, Starla G; Kumar, Manish; Vega, Leticia M; McLean, Robert J C

2017-10-01

Single-celled bacteria are capable of acting as a community by sensing and responding to population density via quorum signalling. Quorum signalling in Chromobacterium violaceum, mediated by the luxI/R homologue, cviI/R, regulates a variety of phenotypes including violacein pigmentation, virulence and biofilm formation. A number of biological and organic molecules have been described as quorum signalling inhibitors but, to date, metal-based inhibitors have not been widely tested. In this study, we show that quorum sensing is inhibited in C. violaceum in the presence of sub-lethal concentrations of cadmium salts. Notable Cd 2+ -inhibition was seen against pigmentation, motility, chitinase production and biofilm formation. Cd-inhibition of quorum-signalling genes occurred at the level of transcription. There was no direct inhibition of chitinase activity by Cd 2+ at the concentrations tested. Addition of the cognate quorum signals, N-hexanoyl homoserine lactone or N-decanoyl homoserine lactone, even at concentrations in excess of physiological levels, did not reverse the inhibition, suggesting that Cd-inhibition of quorum signaling is irreversible. This study represents the first description of heavy metal-based quorum inhibition in C. violaceum.

Citric acid compounds of tangerines peel extract (Citrus reticulata) as potential materials teeth whitening

NASA Astrophysics Data System (ADS)

Pratiwi, F.; Tinata, J. K.; Prakasa, A. W.; Istiqomah; Hartini, E.; Isworo, S.

2017-04-01

Peel of citrus fruit (Citrus reticulata) has a variety of possible chemical compounds that may serve as a potential whitening teeth. This research is conducted on a laboratory scale; therefore, it needs to be developed on an application scale. A quasi-experimental was employed in this study. Citric acid extraction was carried out on the type of Sweet Orange (Citrus Aurantium L), Tangerine (Citrus Reticulata Blanco or Citrus Nobilis), Pomelo (Citrus Maxima Merr, Citrus grandis Osbeck), and Lemon (Citrus Limon Linn). Citric acid’s ability test as teeth whitener was performed on premolar teeth with concentrations of 2.5%, 5%, and 10%. The experiments were replicated in 3 times, and teeth whiteness level was measured using Shade Guide VITA Classical. The result of this research showed that citric acid in every kind of orange peel with various concentration has different abilities on whitening teeth. The highest colour level obtained from Tangerine peel’s citric acid concentration of 5%. Orange peel extract has the best teeth whitening abilities tested by the method of Gass Chromatography to know the active ingredients.

PFCA Article Testing

EPA Science Inventory

The U.S. Environmental Protection Agency (EPA) has established an ongoing effort to quantify possible changes in levels of perfluorinated chemicals (PFCs) in articles of commerce (AOCs). Temporal trends in the concentrations of selected PFCs, including perfluorooctanoic acid (PFO...

Advantages of analyzing postmortem brain samples in routine forensic drug screening-Case series of three non-natural deaths tested positive for lysergic acid diethylamide (LSD).

PubMed

Mardal, Marie; Johansen, Sys Stybe; Thomsen, Ragnar; Linnet, Kristian

2017-09-01

Three case reports are presented, including autopsy findings and toxicological screening results, which were tested positive for the potent hallucinogenic drug lysergic acid diethylamide (LSD). LSD and its main metabolites were quantified in brain tissue and femoral blood, and furthermore hematoma and urine when available. LSD, its main metabolite 2-oxo-3-hydroxy-LSD (oxo-HO-LSD), and iso-LSD were quantified in biological samples according to a previously published procedure involving liquid-liquid extraction and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). LSD was measured in the brain tissue of all presented cases at a concentration level from 0.34-10.8μg/kg. The concentration level in the target organ was higher than in peripheral blood. Additional psychoactive compounds were quantified in blood and brain tissue, though all below toxic concentration levels. The cause of death in case 1 was collision-induced brain injury, while it was drowning in case 2 and 3 and thus not drug intoxication. However, the toxicological findings could help explain the decedent's inability to cope with brain injury or drowning incidents. The presented findings could help establish reference concentrations in brain samples and assist in interpretation of results from forensic drug screening in brain tissue. This is to the author's knowledge the first report of LSD, iso-LSD, and oxo-HO-LSD measured in brain tissue samples. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of Butyric acid concentrations in ordinary and probiotic yogurt samples in Iran.

PubMed

Vaseji, N; Mojgani, N; Amirinia, C; Iranmanesh, M

2012-06-01

Butyric acid has many applications in chemical, food and pharmaceutical industries. Applications of butyric acid are as an additive to food, flavorings, varnishes, perfumes, pharmaceuticals and disinfectants. Butyric acid concentrations have positive impact on the quality control of milk, yogurt and other probiotic dairy products. The present investigation was undertaken to determine and compare the concentrations of butyric acid (C4) in the ordinary and probiotic yogurt samples by GC method. Probiotic yogurt samples were prepared under laboratory scale conditions using two different commercial starters ABY1 and 211, while ordinary yogurt samples lacked the probiotic starter cultures. All samples were analyzed in duplicate, for C4 concentrations by gas chromatography after day 1, 2, 10 and 20 of production, during storage at 4°C. The results were analyzed using ANOVA and Duncan test. The level of the mentioned fatty acid in ABY1 yogurt sample was significantly higher (0.2%) than in 211 samples (0.17%). These values were significantly lower in ordinary yogurt samples and only 0.07% was recorded in these samples on first day of storage which decreased gradually during storage. The level of reduction in the yogurt samples tested during different time intervals was not similar in all the examined samples, and some showed enhanced reduction than other samples. Compared to ordinary yogurt samples, probiotic yogurt samples used in study showed higher levels of butyric acid with increased shelf life.

Comparison of Butyric acid concentrations in ordinary and probiotic yogurt samples in Iran

PubMed Central

Vaseji, N; Mojgani, N; Amirinia, C; Iranmanesh, M

2012-01-01

Background and objectives Butyric acid has many applications in chemical, food and pharmaceutical industries. Applications of butyric acid are as an additive to food, flavorings, varnishes, perfumes, pharmaceuticals and disinfectants. Butyric acid concentrations have positive impact on the quality control of milk, yogurt and other probiotic dairy products. The present investigation was undertaken to determine and compare the concentrations of butyric acid (C4) in the ordinary and probiotic yogurt samples by GC method. Materials and Methods Probiotic yogurt samples were prepared under laboratory scale conditions using two different commercial starters ABY1 and 211, while ordinary yogurt samples lacked the probiotic starter cultures. All samples were analyzed in duplicate, for C4 concentrations by gas chromatography after day 1, 2, 10 and 20 of production, during storage at 4°C. The results were analyzed using ANOVA and Duncan test. Results The level of the mentioned fatty acid in ABY1 yogurt sample was significantly higher (0.2%) than in 211 samples (0.17%). These values were significantly lower in ordinary yogurt samples and only 0.07% was recorded in these samples on first day of storage which decreased gradually during storage. The level of reduction in the yogurt samples tested during different time intervals was not similar in all the examined samples, and some showed enhanced reduction than other samples. Conclusions Compared to ordinary yogurt samples, probiotic yogurt samples used in study showed higher levels of butyric acid with increased shelf life. PMID:22973475

Low levels of nasal nitric oxide (NO) correlate to impaired mucociliary function in the upper airways.

PubMed

Lindberg, S; Cervin, A; Runer, T

1997-09-01

Findings in previous studies have suggested nitric oxide (NO) to be a regulator of mucociliary activity in the upper airways. The aim of the present investigation was to study whether a correlation exists between the nasal NO concentration and mucociliary function in patients suffering from respiratory tract diseases such as chronic sinusitis or recurrent pneumonia. Nasal NO was measured with a chemiluminescence analyser, 100 ppb (parts per billion) being adopted as the lower limit of the normal range on the basis of findings in an earlier study of healthy subjects. Mucociliary function was evaluated by measurements of ciliary beat frequency (CBF) in nasal brush samples, and the saccharin transport test. A subnormal level of nasal NO was found in 50% (9/18) of the patients. This correlated with a significantly impaired mucociliary function, regarding both CBF and the saccharin transport time. The median CBF was 10.6 Hz in the group with normal levels of nasal NO, as compared to 8.4 Hz in the subnormal NO group. All patients with a normal nasal NO concentration had a mean CBF of > or = 9.0 Hz in their nasal brush samples, but in the subnormal group the same measurements yielded a CBF of > or = 9.0 Hz in only 22% (2/9) of the cases. As measured with the saccharin test, mucociliary transport was normal in 78% (7/9) in the normal nasal NO group, but the saccharin test was normal only in 11% (1/9) of the subnormal nasal NO group. Nasal NO levels were found to correlate with both CBF measurements (Spearman's rho, 0.80) and the saccharin transport test results (Spearman's rho, -0.61). The results of the present study provide further support for the view that NO is an important regulator of mucociliary function in the upper airways, and that measurements of the nasal NO concentration should be included in investigations of the mucociliary system.

Evaluation of bilirubin interference and accuracy of six creatinine assays compared with isotope dilution-liquid chromatography mass spectrometry.

PubMed

Nah, Hyunjin; Lee, Sang-Guk; Lee, Kyeong-Seob; Won, Jae-Hee; Kim, Hyun Ok; Kim, Jeong-Ho

2016-02-01

The aim of this study was to estimate bilirubin interference and accuracy of six routine methods for measuring creatinine compared with isotope dilution-liquid chromatography mass spectrometry (ID-LC/MS). A total of 40 clinical serum samples from 31 patients with serum total bilirubin concentration >68.4μmol/L were collected. Serum creatinine was measured using two enzymatic reagents and four Jaffe reagents as well as ID-LC/MS. Correlations between bilirubin concentration and percent difference in creatinine compared with ID-LC/MS were analyzed to investigate bilirubin interference. Bias estimations between the six reagents and ID-LC/MS were performed. Recovery tests using National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 967a were also performed. Both the enzymatic methods showed no bilirubin interference. However, three of the four Jaffe methods demonstrated significant bilirubin concentration-dependent interference in samples with creatinine levels <53μmol/L, and two of them showed significant bilirubin interference in samples with creatinine levels ranging from 53.0 to 97.2μmol/L. Comparison of these methods with ID-LC/MS using patients' samples with elevated bilirubin revealed that the tested methods failed to achieve the bias goal at especially low levels of creatinine. In addition, recovery test using NIST SRM 967a showed that bias in one Jaffe method and two enzymatic methods did not achieve the bias goal at either low or high level of creatinine, indicating they had calibration bias. One enzymatic method failed to achieve all the bias goals in both comparison experiment and recovery test. It is important to understand that both bilirubin interference and calibration traceability to ID-LC/MS should be considered to improve the accuracy of creatinine measurement. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Modification of liposomal concentration in liposome/adenoviral complexes allows significant protection of adenoviral vectors from neutralising antibody, in vitro.

PubMed

Steel, Jason C; Cavanagh, Heather M A; Burton, Mark A; Dingwall, Daniel J; Kalle, Wouter H J

2005-06-01

Adenoviral vectors have been commonly used in gene therapy protocols, however the success of their use is often limited by the induction of host immunity to the vector. Following exposure to the adenoviral vector, adenoviral-specific neutralising antibodies are produced which limits further administration. This study examines the efficacy of complexing liposomes to adenovirus for the protection of the adenovirus from neutralising antibodies in an in vitro setting. Dimethyldioctadecylammonium bromide (DDAB)-dioleoyl-l-phosphatidylethanolamine (DOPE) liposomes were bound at varying concentrations to adenovirus to form AL complexes and tested these complexes' ability to prevent adenoviral neutralisation. It is shown that by increasing the concentration of liposomes in the adenoviral-liposome (AL) complexes we can increase the level of immuno-shielding afforded the adenovirus. It is also shown that the increase in liposomal concentration may lead to drawbacks such as increased cytotoxicity and reductions in expression levels.

Effects of export concentration on CO2 emissions in developed countries: an empirical analysis.

PubMed

Apergis, Nicholas; Can, Muhlis; Gozgor, Giray; Lau, Chi Keung Marco

2018-03-08

This paper provides the evidence on the short- and the long-run effects of the export product concentration on the level of CO 2 emissions in 19 developed (high-income) economies, spanning the period 1962-2010. To this end, the paper makes use of the nonlinear panel unit root and cointegration tests with multiple endogenous structural breaks. It also considers the mean group estimations, the autoregressive distributed lag model, and the panel quantile regression estimations. The findings illustrate that the environmental Kuznets curve (EKC) hypothesis is valid in the panel dataset of 19 developed economies. In addition, it documents that a higher level of the product concentration of exports leads to lower CO 2 emissions. The results from the panel quantile regressions also indicate that the effect of the export product concentration upon the per capita CO 2 emissions is relatively high at the higher quantiles.

Air pollution & the brain: Subchronic diesel exhaust exposure causes neuroinflammation and elevates early markers of neurodegenerative disease.

PubMed

Levesque, Shannon; Surace, Michael J; McDonald, Jacob; Block, Michelle L

2011-08-24

Increasing evidence links diverse forms of air pollution to neuroinflammation and neuropathology in both human and animal models, but the effects of long-term exposures are poorly understood. We explored the central nervous system consequences of subchronic exposure to diesel exhaust (DE) and addressed the minimum levels necessary to elicit neuroinflammation and markers of early neuropathology. Male Fischer 344 rats were exposed to DE (992, 311, 100, 35 and 0 μg PM/m³) by inhalation over 6 months. DE exposure resulted in elevated levels of TNFα at high concentrations in all regions tested, with the exception of the cerebellum. The midbrain region was the most sensitive, where exposures as low as 100 μg PM/m³ significantly increased brain TNFα levels. However, this sensitivity to DE was not conferred to all markers of neuroinflammation, as the midbrain showed no increase in IL-6 expression at any concentration tested, an increase in IL-1β at only high concentrations, and a decrease in MIP-1α expression, supporting that compensatory mechanisms may occur with subchronic exposure. Aβ42 levels were the highest in the frontal lobe of mice exposed to 992 μg PM/m³ and tau [pS199] levels were elevated at the higher DE concentrations (992 and 311 μg PM/m³) in both the temporal lobe and frontal lobe, indicating that proteins linked to preclinical Alzheimer's disease were affected. α Synuclein levels were elevated in the midbrain in response to the 992 μg PM/m³ exposure, supporting that air pollution may be associated with early Parkinson's disease-like pathology. Together, the data support that the midbrain may be more sensitive to the neuroinflammatory effects of subchronic air pollution exposure. However, the DE-induced elevation of proteins associated with neurodegenerative diseases was limited to only the higher exposures, suggesting that air pollution-induced neuroinflammation may precede preclinical markers of neurodegenerative disease in the midbrain.

A practical derivatization LC/MS approach for determination of trace level alkyl sulfonates and dialkyl sulfates genotoxic impurities in drug substances.

PubMed

An, Jianguo; Sun, Mingjiang; Bai, Lin; Chen, Ted; Liu, David Q; Kord, Alireza

2008-11-04

Derivatization LC/MS methodology has been developed for the determination of a group of commonly encountered alkyl esters of sulfonates or sulfates in drug substances at low ppm levels. This general method uses trimethylamine as the derivatizing reagent for ethyl/propyl/isopropyl esters and triethylamine for methyl esters. The resulting quaternary ammonium derivatization products are highly polar (ionic) and can be retained by a hydrophilic interaction liquid chromatography (HILIC) column and readily separated from the main interfering active pharmaceutical ingredient (API) peak that is usually present at very high concentration. The method gives excellent sensitivity for all the alkyl esters at typical target analyte level of 1-2 ppm when the API samples were prepared at 5mg/mL. The recoveries at 1-2 ppm were generally above 85% for all the alkyl esters in the various APIs tested. The injection precisions of the lowest concentration standards were excellent with R.S.D.=0.4-4%. A linear range for concentrations from 0.2 to 20 ppm has been established with R(2)>or=0.99. This general method has been tested in a number of API matrices and used successfully for determination of alkyl sulfonates or dialkyl sulfates in support of API batch releases at GlaxoSmithKline.

Comparative Analysis of Nitrate Levels in Pensacola Area Rain Water

NASA Astrophysics Data System (ADS)

Jacobs, J.; Caffrey, J. M.; Maestre, A.; Landing, W. M.

2017-12-01

Nitrate is an important constituent of acid rain and often correlated with atmospheric NOx levels. This link between air and water quality was tested over a course of summer 2017 and compared to data from 2005-2012. Rain water samples collected from late May through early July of 2017 were tested for pH and nitrate concentrations. These months were among the stormiest on record for the Northwest Florida region with a total rainfall of 648 mm. The data analyzed from these rain events was compared to previous data to show the trends of nitrate and pH levels in the rainwater. Median pH for this study was 5.2, higher than the medians between 2015-2012 which ranged from 4.2 to 5.0, while nitrate concentrations for this study were 15.2 µM. This contrasts with a significant drop in nitrate concentrations from 41 µM in 2005 and 2006 to around 12 µM between 2007 and 2012. The drop between 2006-7 was suspected to be a result of implementation of NOx controls at Plant Crist coal fired power plant and other Clean Air Act requirements. These inputs of nitrate and H+ ions from rainwater can have a significant influence water quality throughout the region.

Evaluating regional trends in ground-water nitrate concentrations of the Columbia Basin ground water management area, Washington

USGS Publications Warehouse

Frans, Lonna M.; Helsel, Dennis R.

2005-01-01

Trends in nitrate concentrations in water from 474 wells in 17 subregions in the Columbia Basin Ground Water Management Area (GWMA) in three counties in eastern Washington were evaluated using a variety of statistical techniques, including the Friedman test and the Kendall test. The Kendall test was modified from its typical 'seasonal' version into a 'regional' version by using well locations in place of seasons. No statistically significant trends in nitrate concentrations were identified in samples from wells in the GWMA, the three counties, or the 17 subregions from 1998 to 2002 when all data were included in the analysis. For wells in which nitrate concentrations were greater than 10 milligrams per liter (mg/L), however, a significant downward trend of -0.4 mg/L per year was observed between 1998 and 2002 for the GWMA as a whole, as well as for Adams County (-0.35 mg/L per year) and for Franklin County (-0.46 mg/L per year). Trend analysis for a smaller but longer-term 51-well dataset in Franklin County found a statistically significant upward trend in nitrate concentrations of 0.1 mg/L per year between 1986 and 2003. The largest increase of nitrate concentrations occurred between 1986 and 1991. No statistically significant differences were observed in this dataset between 1998 and 2003 indicating that the increase in nitrate concentrations has leveled off.

Statistical analysis of the radon-222 potential of rocks in Virginia, U.S.A.

USGS Publications Warehouse

Brown, C. Erwin; Mose, D.G.; Mushrush, G.W.; Chrosniak, C.E.

1992-01-01

More than 3,200 indoor radon-222 (222Rn) measurements were made seasonally in an area of about 1,000 square kilometers of the Coastal Plain and Piedmont physiographic provinces in Virginia, U.S.A. Results of these measurements indicate that some geological units are associated, on the average, with twice as much indoor222Rn as other geological units, and that indoor222Rn varies seasonally. The Kruskal-Wallis test was used to test whether indoor222Rn concentrations for data gathered over the winter and summer seasons differ significantly by rock unit. The tests concluded that indoor222Rn concentrations for different rock units were not equal at the 5-percent significance level. The rocks associated with the highest median indoor222Rn concentration are specific rocks in the Mesozoic Culpeper basin, including shale and siltstone units with Jurassic diabase intrusives, and mica schists in the Piedmont physiographic province. The pre-Triassic Peters Creek Schist has the highest ranking in terms of indoor222Rn concentration. The rocks associated with the lowest indoor222Rn concentrations include coastal plain sediments, the Occoquan Granite, Falls Church Tonalite, Piney Branch Mafic and Ultramafic complex, and unnamed mafic and ultramafic inclusions, respectively. The rocks have been ranked according to observed222Rn concentration by transforming the average rank of indoor222Rn concentrations to z scores. ?? 1992 Springer-Verlag New York Inc.

The pollution removal and stormwater reduction performance of street-side bioretention basins after ten years in operation.

PubMed

Lucke, Terry; Nichols, Peter W B

2015-12-01

This study evaluated the pollution removal and hydrologic performance of five, 10-year old street-side bioretention systems. The bioretention basins were subjected to a series of simulated rainfall events using synthetic stormwater. Four different pollution concentrations were tested on three of the bioretention basins. The four concentrations tested were: A) no pollution; B) typical Australian urban pollutant loads; C) double the typical pollution loads, and; D) five times the typical pollution loads. Tests were also undertaken to determine the levels of contaminant and heavy metals build-up that occurred in the filter media over the 10 year operational life of the bioretention systems. Although highly variable, the overall hydrological performance of the basins was found to be positive, with all basins attenuating flows, reducing both peak flow rates and total outflow volumes. Total suspended solids removal performance was variable for all tests and no correlation was found between performance and dosage. Total nitrogen (TN) removal was positive for Tests B, C and D. However, the TN removal results for Test A were found to be negative. Total phosphorus (TP) was the only pollutant to be effectively removed from all basins for all four synthetic stormwater tests. The study bioretention basins were found to export pollutants during tests where no pollutants were added to the simulated inflow water (Test A). Heavy metal and hydrocarbon testing undertaken on the bioretention systems found that the pollution levels of the filter media were still within acceptable limits after 10 years in operation. This field study has shown bioretention basin pollution removal performance to be highly variable and dependant on a range of factors including inflow pollution concentrations, filter media, construction methods and environmental factors. Further research is required in order to fully understand the potential stormwater management benefits of these systems. Copyright © 2015 Elsevier B.V. All rights reserved.

Arsenic and Other Metals’ Presence in Biomarkers of Cambodians in Arsenic Contaminated Areas

PubMed Central

Chanpiwat, Penradee; Himeno, Seiichiro; Sthiannopkao, Suthipong

2015-01-01

Chemical analyses of metal (Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Mo, Ba, and Pb) concentrations in hair, nails, and urine of Cambodians in arsenic-contaminated areas who consumed groundwater daily showed elevated levels in these biomarkers for most metals of toxicological interest. The levels of metals in biomarkers corresponded to their levels in groundwater, especially for As, whose concentrations exceeded the WHO guidelines for drinking water. About 75.6% of hair samples from the population in this study contained As levels higher than the normal level in unexposed individuals (1 mg·kg−1). Most of the population (83.3%) showed As urinary levels exceeding the normal (<50 ng·mg−1). These results indicate the possibility of arsenicosis symptoms in residents of the areas studied. Among the three biomarkers tested, hair has shown to be a reliable indicator of metal exposures. The levels of As (r2 = 0.633), Ba (r2 = 0.646), Fe (r2 = 0.595), and Mo (r2 = 0.555) in hair were strongly positively associated with the levels of those metals in groundwater. In addition, significant weak correlations (p < 0.01) were found between levels of exposure to As and As concentrations in both nails (r2 = 0.544) and urine (r2 = 0.243). PMID:26569276

Correcting for the influence of sampling conditions on biomarkers of exposure to phenols and phthalates: a 2-step standardization method based on regression residuals.

PubMed

Mortamais, Marion; Chevrier, Cécile; Philippat, Claire; Petit, Claire; Calafat, Antonia M; Ye, Xiaoyun; Silva, Manori J; Brambilla, Christian; Eijkemans, Marinus J C; Charles, Marie-Aline; Cordier, Sylvaine; Slama, Rémy

2012-04-26

Environmental epidemiology and biomonitoring studies typically rely on biological samples to assay the concentration of non-persistent exposure biomarkers. Between-participant variations in sampling conditions of these biological samples constitute a potential source of exposure misclassification. Few studies attempted to correct biomarker levels for this error. We aimed to assess the influence of sampling conditions on concentrations of urinary biomarkers of select phenols and phthalates, two widely-produced families of chemicals, and to standardize biomarker concentrations on sampling conditions. Urine samples were collected between 2002 and 2006 among 287 pregnant women from Eden and Pélagie cohorts, from which phthalates and phenols metabolites levels were assayed. We applied a 2-step standardization method based on regression residuals. First, the influence of sampling conditions (including sampling hour, duration of storage before freezing) and of creatinine levels on biomarker concentrations were characterized using adjusted linear regression models. In the second step, the model estimates were used to remove the variability in biomarker concentrations due to sampling conditions and to standardize concentrations as if all samples had been collected under the same conditions (e.g., same hour of urine collection). Sampling hour was associated with concentrations of several exposure biomarkers. After standardization for sampling conditions, median concentrations differed by--38% for 2,5-dichlorophenol to +80 % for a metabolite of diisodecyl phthalate. However, at the individual level, standardized biomarker levels were strongly correlated (correlation coefficients above 0.80) with unstandardized measures. Sampling conditions, such as sampling hour, should be systematically collected in biomarker-based studies, in particular when the biomarker half-life is short. The 2-step standardization method based on regression residuals that we proposed in order to limit the impact of heterogeneity in sampling conditions could be further tested in studies describing levels of biomarkers or their influence on health.

FY 1993 report on aluminum-nitrate testing at the ETF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goodman, M.D.D.; Wise, M.D.

1993-09-30

This report summarizes the progress of the Aluminum Nitrate Nonhydrate (ANN) testing program at the F/H-Area Effluent Treatment Facility (ETF) for Fiscal Year 1993. Three tests were conducted in the months of February, April, and September. The tests yielded data that validated earlier conclusions that the addition of ANN to non-routine feed has a positive effect on the performance of ETF`s submicron filtration unit. Performance was observed to increase from 30--309%, depending on the season. The data also supports SRTC`s earlier conclusion that an optimal aluminum concentration exists in the range of 30--40 ppm, and concentrations above this range beginmore » to retard filtration performance. A rudimentary mathematical model that would predict Stage 1 flux was also developed during FY93. The model allowed for a more concise comparison of filter test runs, as well as increase the efficiency of the testing program by allowing shorter test runs to be conducted. It is postulated that the model can be further optimized to include aluminum concentration and time of year as independent variables that determine Stage 1 flux. Such a model should unequivocally prove the merits of pretreating ETF`s wastewater with aluminum nitrate. To proceed with the development of the model, further testing is proposed with stringent control of the aluminum concentration in the feed. In order to account for seasonal effects, one test should be conducted each month for Fiscal Year 1994. High Level Waste Engineering requests permission to conduct these test runs according to the following schedule: conduct tests in even numbered months beginning with October with routine influent as it is collected from normal process sewer influents and conduct tests in odd numbered months beginning with November with non-routine feed from H-Retention Basin.« less

Effect of nitrate concentration on filamentous bulking under low level of dissolved oxygen in an airlift inner circular anoxic-aerobic incorporate reactor.

PubMed

Su, Yiming; Zhang, Yalei; Zhou, Xuefei; Jiang, Ming

2013-09-01

This laboratory research investigated a possible cause of filamentous bulking under low level of dissolved oxygen conditions (dissolved oxygen value in aerobic zone maintained between 0.6-0.8 mg O2/L) in an airlift inner-circular anoxic-aerobic reactor. During the operating period, it was observed that low nitrate concentrations affected sludge volume index significantly. Unlike the existing hypothesis, the batch tests indicated that filamentous bacteria (mainly Thiothrix sp.) could store nitrate temporarily under carbon restricted conditions. When nitrate concentration was below 4 mg/L, low levels of carbon substrates and dissolved oxygen in the aerobic zone stimulated the nitrate-storing capacity of filaments. When filamentous bacteria riched in nitrate reached the anoxic zone, where they were exposed to high levels of carbon but limited nitrate, they underwent denitrification. However, when nonfilamentous bacteria were exposed to similar conditions, denitrification was restrained due to their intrinsic nitrate limitation. Hence, in order to avoid filamentous bulking, the nitrate concentration in the return sludge (from aerobic zone to the anoxic zone) should be above 4 mg/L, or alternatively, the nitrate load in the anoxic zone should be kept at levels above 2.7 mg NO(3-)-N/g SS.

Determination of heavy metal levels in water, sediment and tissues of tench (Tinca tinca L., 1758) from Beyşehir Lake (Turkey).

PubMed

Tekin-Ozan, Selda

2008-10-01

In the present study, some heavy metals (Cu, Fe, Zn and Mn) were seasonally determined in water, sediment and some tissues of fish Tinca tinca from Beyşehir Lake, which is an important bird nesting and visiting area, a water source for irrigation and drinking. In the water, Fe has the highest concentrations among the studied metals. Generally, the metal concentrations increased in the hottest period decreased in warm seasons. Results for levels in water were compared with national and international water quality guidelines, as well as literature data reported for the lakes. Fe was the highest in sediment samples, also Cu and Zn were the highest in spring, while Fe and Mn were in autumn. Among the heavy metals studied, Cu and Mn were below the detection limits in some tissues. Generally, higher concentrations of the tested metals were found in the summer and winter, compared with those during the autumn and spring seasons. High levels of heavy metals were found in liver of T. tinca, while low levels in muscle samples. Metal concentrations in the muscle of examined fish were within the safety permissible levels for human consumption. The present study shows that precautions need to be taken in order to prevent further heavy metal pollution.

Exposure assessment of JAVELIN missile combustion products

NASA Astrophysics Data System (ADS)

Lundy, Donald O.; Langford, Roland E.

1994-02-01

Characterization and analysis of combustion products resulting from firing the JAVELIN missile were performed. Of those combustion products analyzed, it was determined that airborne lead concentrations exceeded the OSHA PEL of 50 micrograms each time the missile was fired while in the enclosure. Since the OSHA PEL standard is based upon a continuous rather than a short-term exposures blood lead concentrations were sought to ascertain the relationship between a short duration airborne exposure and its physiological effect on the body. Blood lead levels were taken on 49 test subjects prior to various JAVELIN missile test firings. Of those 49, 21 were outfitted With personal sampling equipment to determine airborne concentrations at the Assistant Gunner and Gunner positions. Periodic blood sampling after a single exposure showed an average increase of 2.27 micrograms/dL for all test subjects. Recommendations were made to consider changes in the positioning of the enclosure inhabitants to minimize airborne lead concentrations, to limit the number of missiles fired (situation dependent), and replacement of the lead B-resorcyolate with a non-lead containing burn rate modifier for the launch motor.

Environmental PCBs in Guánica Bay, Puerto Rico: implications for community health.

PubMed

Kumar, Naresh; Ramirez-Ortiz, Daisy; Solo-Gabriele, Helena M; Treaster, Joseph B; Carrasquillo, Olveen; Toborek, Michal; Deo, Sapna; Klaus, Jim; Bachas, Leonidas G; Whitall, David; Daunert, Sylvia; Szapocznik, Jose

2016-02-01

Guánica Bay, located in southwestern Puerto Rico, has suffered oil spills and other pollution discharges since the 1960s. Previous research showed elevated concentrations of polychlorinated biphenyls (PCBs) in coral reef and sediment. This research examined PCB concentrations in sediment and fish. Sediment and fish sampling in the bay was facilitated by community members. This study identified the second highest reported PCB level (129,300 ng/g) in sediment in the USA. Fish samples also showed elevated concentrations (1623 to 3768 ng/g), which were higher than the thresholds of safe levels of PCBs in fish for human consumption. The alarmingly high concentration of PCBs calls for proactive community engagement to bring awareness about contamination of the bay and more extensive sampling to test for the concentration of PCBs in seafood and the people of Guánica. This study also underscores the value of the involvement of local communities during sampling design aimed at identifying hot spots of contaminants.

[Abnormal metabolism of triglycerides fractions in chronic pancreatitis and results after the operation treatment].

PubMed

Diakowska, Dorota; Knast, Witold; Diakowski, Witold; Grabowski, Krzysztof; Szelachowski, Piotr; Pelczar, Piotr

2005-06-01

This study was undertaken to determine how fats digestion processes were damaged due to chronic pancreatitis, and identify, whether lipid metabolism improved after surgical treatment the patients with chronic pancreatitis. Total lipids, triglycerides, diglycerides and free fatty acids levels in serum and stool were analysed, using chemical tests, thin-layer chromatography and electrophoresis of serum lipoproteins. The patients before the operations showed higher total lipids and triglycerides concentrations, and lower concentrations of diglycerides and free fatty acids in stool. These patients had high triglycerides, chylomicrons, VLDL, LDL-CH concentrations, and low-diglycerides, free fatty acids, HDL-CH concentrations in serum. These data were statistically significant. After the operations and substitution therapy it was observed normalization of the total lipids and lipids fractions levels in stool and in serum. Concentrations of LDL-CH and HDL-CH fractions were irregular. We conclude, that these lipids parameters could be used in diagnosing and monitoring the results of chronic pancreatitis surgical treatment.

+2 Valence Metal Concentrations in Lion Creek, Oakland, California

NASA Astrophysics Data System (ADS)

Vazquez, P.; Zedd, T.; Chagolla, R.; Dutton-Starbuck, M.; Negrete, A.; Jinham, M.; Lapota, M.

2012-12-01

Seven major creeks exist within the City of Oakland, California. These creeks all flow in the southwest direction from forested hills down through densely populated streets where they become susceptible to urban runoff. Lion Creek has been diverted to engineered channels and underground culverts and runs directly under our school (Roots International) before flowing into the San Leandro Bay. One branch of the creek begins near an abandoned sulfur mine. Previous studies have shown that extremely high levels of lead, arsenic and iron exist in this portion of the creek due to acid mine drainage. In this study +2 valence heavy metals concentration data was obtained from samples collected from a segment of the creek located approximately 2.8 miles downstream from the mine. Concentrations in samples collected at three different sites along this segment ranged between 50 ppb and 100 ppb. We hypothesize that these levels are related to the high concentration of +2 valence heavy metals at the mining site. To test this hypothesis, we have obtained samples from various locations along the roughly 3.75 miles of Lion Creek that are used to assess changes in heavy metals concentration levels from the mining site to the San Leandro Bay.

Does IGF-1 play a role in the biology of ovarian cancer?

PubMed

Majchrzak-Baczmańska, Dominika; Malinowski, Andrzej; Głowacka, Ewa; Wilczyński, Miłosz

2018-01-01

The aim of the study was to investigate serum concentrations of the insulin-like growth factor-1 in women with ovarian cancer and healthy controls, and to compare free IGF-1 levels with selected clinical and pathological param-eters. Correlation analysis was used to measure the following: IGF-1 concentration and Ca125; IGF-1 level and the height of the OC patients. The study included 70 patients with OC and 50 healthy controls. Serum concentrations of free IGF-1 were measured in all subjects. Routine diagnostic tests (CBC and USG and Ca125) were performed. Significantly higher serum concentrations of free IGF-1 were found in the study group as compared to controls. No statistically significant relationships between IGF-1 serum concentrations and tumor differentiation, histological type, and disease stage were detected. No statistically significant correlations between IGF-1 and Ca125 level or between IGF-1 and growth of OC patients were found. Serum IGF-1 participates in the etiopathogenesis of ovarian cancer in menstruating women, while local synthesis of this factor and other components of the autocrine loop of the IGF-1 system play a greater role in their post-menopausal peers.

Multilevel microvibration test for performance predictions of a space optical load platform

NASA Astrophysics Data System (ADS)

Li, Shiqi; Zhang, Heng; Liu, Shiping; Wang, Yue

2018-05-01

This paper presents a framework for the multilevel microvibration analysis and test of a space optical load platform. The test framework is conducted on three levels, including instrument, subsystem, and system level. Disturbance source experimental investigations are performed to evaluate the vibration amplitude and study vibration mechanism. Transfer characteristics of space camera are validated by a subsystem test, which allows the calculation of transfer functions from various disturbance sources to optical performance outputs. In order to identify the influence of the source on the spacecraft performance, a system level microvibration measurement test has been performed on the ground. From the time domain analysis and spectrum analysis of multilevel microvibration tests, we concluded that the disturbance source has a significant effect on its installation position. After transmitted through mechanical links, the residual vibration reduces to a background noise level. In addition, the angular microvibration of the platform jitter is mainly concentrated in the rotation of y-axes. This work is applied to a real practical application involving the high resolution satellite camera system.

Neurotoxicity produced by dibromoacetic acid in drinking water of rats.

PubMed

Moser, V C; Phillips, P M; Levine, A B; McDaniel, K L; Sills, R C; Jortner, B S; Butt, M T

2004-05-01

An evaluation of potential adverse human health effects of disinfection byproducts requires study of both cancer and noncancer endpoints; however, no studies have evaluated the neurotoxic potential of a common haloacetic acid, dibromoacetic acid (DBA). This study characterized the neurotoxicity of DBA during 6-month exposure in the drinking water of rats. Adolescent male and female Fischer 344 rats were administered DBA at 0, 0.2, 0.6, and 1.5 g/l. On a mg/kg/day basis, the consumed dosages decreased greatly over the exposure period, with average intakes of 0, 20, 72, and 161 mg/kg/day. Weight gain was depressed in the high-concentration group, and concentration-related diarrhea and hair loss were observed early in exposure. Testing with a functional observational battery and motor activity took place before dosing and at 1, 2, 4, and 6 months. DBA produced concentration-related neuromuscular toxicity (mid and high concentrations) characterized by limb weakness, mild gait abnormalities, and hypotonia, as well as sensorimotor depression (all concentrations), with decreased responses to a tail-pinch and click. Other signs of toxicity at the highest concentration included decreased activity and chest clasping. Neurotoxicity was evident as early as one month, but did not progress with continued exposure. The major neuropathological finding was degeneration of spinal cord nerve fibers (mid and high concentrations). Cellular vacuolization in spinal cord gray matter (mostly) and in white matter (occasionally) tracts was also observed. No treatment-related changes were seen in brain, eyes, peripheral nerves, or peripheral ganglia. The lowest-observable effect level for neurobehavioral changes was 20 mg/kg/day (produced by 0.2 g/l, lowest concentration tested), whereas this dosage was a no-effect level for neuropathological changes. These studies suggest that neurotoxicity should be considered in the overall hazard evaluation of haloacetic acids.

FY2011 Progress Report: Agreement 8697 - NOx Sensor Development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Woo, L Y; Glass, R S

Objectives are: (1) Develop an inexpensive, rapid-response, high-sensitivity and selective electrochemical sensor for oxides of nitrogen (NO{sub x}) for compression-ignition, direct-injection (CIDI) OBD II systems; (2) Explore and characterize novel, effective sensing methodologies based on impedance measurements and designs and manufacturing methods that are compatible with mass fabrication; and (3) Collaborate with industry in order to (ultimately) transfer the technology to a supplier for commercialization. Approach used is: (1) Use an ionic (O{sup 2-}) conducting ceramic as a solid electrolyte and metal or metal-oxide electrodes; (2) Correlate NO{sub x} concentration with changes in cell impedance; (3) Evaluate sensing mechanisms andmore » aging effects on long-term performance using electrochemical techniques; and (4) Collaborate with Ford Research Center to optimize sensor performance and perform dynamometer and on-vehicle testing. Work in FY2011 focused on using an algorithm developed in FY2010 in a simplified strategy to demonstrate how data from controlled laboratory evaluation could be applied to data from real-world engine testing. The performance of a Au wire prototype sensor was evaluated in the laboratory with controlled gas compositions and in dynamometer testing with diesel exhaust. The laboratory evaluation indicated a nonlinear dependence of the NO{sub x} and O{sub 2} sensitivity with concentration. For both NO{sub x} and O{sub 2}, the prototype sensor had higher sensitivity at concentrations less than {approx}20 ppm and {approx}7%, respectively, compared to lower NO{sub x} and O{sub 2} sensitivity at concentrations greater than {approx}50 ppm and {approx}10.5%, respectively. Results in dynamometer diesel exhaust generally agreed with the laboratory results. Diesel exhaust after-treatment systems will likely require detection levels less than {approx}20 ppm in order to meet emission regulations. The relevant mathematical expressions for sensitivity in different concentration regimes obtained from bench-level laboratory evaluation were used to adjust the sensor signal in dynamometer testing. Both NO{sub x} and O{sub 2} exhibited non-linear responses over the concentration regimes examined (0-100 ppm for NO{sub x} and 4-7% for O{sub 2}). Adjusted sensor signals had better agreement with both a commercial NO{sub x} sensor and FTIR measurements. However, the lack of complete agreement indicated that it was not possible to completely account for the nonlinear sensor behavior in certain concentration regimes. The agreement at lower NO{sub x} levels (less than 20 ppm) was better than at higher levels (50-100 ppm). Other progress in FY2011 included dynamometer testing of sensors with imbedded heaters and protective housings that were mounted directly into the exhaust manifold. Advanced testing protocols were used to evaluate the sensors. These experiments confirmed the potential for sensor robustness and durability. Advanced material processing methods appropriate for mass manufacturing, such as sputtering, are also being evaluated. A major milestone for this past year was the licensing of the LLNL NO{sub x} sensor technology to EmiSense Technologies, LLC. EmiSense has extensive experience and resources for the development of emission control sensors. A CRADA is in development that will allow LLNL to work in partnership with EmiSense to bring the LLNL NO{sub x} sensor technology to commercialization. Ford Motor Company is also a partner in this effort.« less

System Design Verification for Closed Loop Control of Oxygenation With Concentrator Integration.

PubMed

Gangidine, Matthew M; Blakeman, Thomas C; Branson, Richard D; Johannigman, Jay A

2016-05-01

Addition of an oxygen concentrator into a control loop furthers previous work in autonomous control of oxygenation. Software integrates concentrator and ventilator function from a single control point, ensuring maximum efficiency by placing a pulse of oxygen at the beginning of the breath. We sought to verify this system. In a test lung, fraction of inspired oxygen (FIO2) levels and additional data were monitored. Tests were run across a range of clinically relevant ventilator settings in volume control mode, for both continuous flow and pulse dose flow oxygenation. Results showed the oxygen concentrator could maintain maximum pulse output (192 mL) up to 16 breaths per minute. Functionality was verified across ranges of tidal volumes and respiratory rates, with and without positive end-expiratory pressure, in continuous flow and pulse dose modes. For a representative test at respiratory rate 16 breaths per minute, tidal volume 550 mL, without positive end-expiratory pressure, pulse dose oxygenation delivered peak FIO2 of 76.83 ± 1.41%, and continuous flow 47.81 ± 0.08%; pulse dose flow provided a higher FIO2 at all tested setting combinations compared to continuous flow (p < 0.001). These tests verify a system that provides closed loop control of oxygenation while integrating time-coordinated pulse-doses from an oxygen concentrator. This allows the most efficient use of resources in austere environments. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

Evaluation of four commercial natural products for repellency and toxicity against the lone star tick, Amblyomma americanum (Acari: Ixodidae).

PubMed

Machtinger, Erika T; Li, Andrew Y

2017-12-01

Lone star ticks are aggressive ectoparasites of domestic and wild animals, as well as humans. These ticks can transmit many pathogens that cause disease including Erhlichia and tularemia. Common compounds used for personal protection and area sprays are N-diethyl-3-methyl benzamide (DEET) and permethrin, but public concern over personal and environmental safety require the development of new, safer products. In the current study, four commercially available products (Wondercide, Essentria IC 3 , Vet's Best, and Mosquito Barrier) were tested for both repellent and toxic effects against lone star tick nymphs and adults. Overall, all four products were more effective against nymphs than against adults. Wondercide and Essentria IC 3 were as toxic to nymphs as permethrin at concentrations of 3.13% and higher, and as repellent as DEET at all concentrations. Nymphs were also repelled by Mosquito Barrier and Vet's Best, but these products had about half or less of the repellent effects of Wondercide and Essentria IC 3 at most of the concentrations. Adult ticks were repelled similarly by all products at all tested concentrations, but at lower levels than nymphs. Toxicity of the four tested products on adults was similar at concentrations of 12.5% and below, less than half of what was observed with permethrin with declining effectiveness as concentrations decreased. Overall, these four products may offer a natural way to repel lone star ticks, but further field testing is needed to determine rates of application and residual activity.

Inflammation and psychotropic drugs: the relationship between C-reactive protein and antipsychotic drug levels.

PubMed

Hefner, Gudrun; Shams, Mohamed E E; Unterecker, Stefan; Falter, Tanja; Hiemke, Christoph

2016-05-01

In psychiatric clinical practice, there is a need to identify psychotropic drugs whose metabolisms are prone to be altered with increased inflammatory activity in an individual patient. The aim of this study was to find out whether elevated serum levels (≥5 mg/l) of C-reactive protein (CRP), an established laboratory marker of infection and inflammation, are associated with increased serum concentrations of the atypical antipsychotic drugs clozapine, quetiapine, and risperidone. Therapeutic drug monitoring request forms of patients whose antipsychotic drug concentrations had been measured under conditions of normal (<5 mg/l) and pathological (>5 mg/l) levels of C-reactive protein were retrospectively screened. The serum concentrations in relation to the daily doses [concentration per dose (C/D) (ng/mL/mg)] and the metabolic ratios [ratio of concentrations (metabolite/drug)] were compared intraindividually by the Wilcoxon signed rank test. To the study effects of the intensity of infections on drug concentrations, C-reactive protein and C/D levels were submitted to Spearman's correlation analysis. Elevated levels of C-reactive protein were found in 105 patients. They were significantly associated with elevated values in C/D for clozapine (n = 33, P < 0.01) and risperidone (n = 40, P < 0.01). A trend for an increase was found for quetiapine (n = 32, P = 0.05). Median increases were 48.0 % (clozapine), 11.9 % (quetiapine), and 24.2 % (active moiety of risperidone), respectively. In patients who exhibit signs of inflammation or infection with increased C-reactive protein values during psychopharmacological treatment, especially under clozapine and risperidone, therapeutic drug monitoring is recommendable in order to minimize the risk of intoxications due to elevated drug concentrations.

Combined pituitary hormone deficiency in german shepherd dogs with dwarfism.

PubMed

Kooistra, H S; Voorhout, G; Mol, J A; Rijnberk, A

2000-10-01

In German shepherd dogs pituitary dwarfism is known as an autosomal recessive inherited abnormality. To investigate whether the function of cells other than the somatotropes may also be impaired in this disease, the secretory capacity of the pituitary anterior lobe (AL) cells was studied by a combined pituitary AL stimulation test with four releasing hormones (4RH test) in four male and four female German shepherd dwarfs. In addition, the morphology of the pituitary was investigated by computed tomography. The physical features of the eight German shepherd dwarfs were primarily characterized by growth retardation and stagnant development of the hair coat. The results of the 4RH test confirmed the presence of hyposomatotropism. The basal plasma TSH and prolactin concentrations were also low and did not change upon stimulation. Basal plasma concentrations of LH were relatively low and responded only slightly to suprapituitary stimulation. With respect to the plasma FSH levels there was a clear gender difference. In the males plasma FSH concentrations remained below the detection limit throughout the 4RH test, whereas in the females the basal plasma FSH levels were slightly lower and there was only a small increase following suprapituitary stimulation, compared with the values in age-matched controls. In contrast, basal and stimulated plasma ACTH concentrations did not differ between the dwarfs and the controls. Computed tomography of the pituitary fossa revealed a normal sized pituitary with cysts in five dogs, an enlarged pituitary with cysts in two dogs, and a small pituitary gland without cysts in the remaining dog. The results of this study demonstrate that German shepherd dwarfs have a combined deficiency of GH, TSH, and prolactin together with impaired release of gonadotropins, whereas ACTH secretion is preserved. The combined pituitary hormone deficiency is associated with cyst formation and pituitary hypoplasia.

Low unesterified:esterified eicosapentaenoic acid (EPA) plasma concentration ratio is associated with bipolar disorder episodes, and omega-3 plasma concentrations are altered by treatment

PubMed Central

Saunders, Erika FH; Reider, Aubrey; Singh, Gagan; Gelenberg, Alan J; Rapoport, Stanley I

2015-01-01

Objectives Omega (n)-3 and n-6 polyunsaturated fatty acids (PUFA) are molecular modulators of neurotransmission and inflammation. We hypothesized that plasma concentrations of n-3 PUFA would be lower and of n-6 PUFA higher in subjects with bipolar disorder (BD) compared to healthy controls (HC), and would correlate with symptom severity in subjects with BD, and that effective treatment would correlate with increased n-3 but lower n-6 PUFA levels. Additionally, we explored clinical correlations and group differences in plasma levels of saturated and monounsaturated fatty acids. Methods This observational, parallel group study compared biomarkers between HC (n = 31), and symptomatic subjects with BD (n = 27) when ill and after symptomatic recovery (follow-up). Plasma concentrations of five PUFA [linoleic acid (LA), arachidonic acid (AA), alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA)], of two saturated fatty acids (palmitic acid and stearic acid) and of two monounsaturated fatty acids (palmitoleic acid, oleic acid) were measured in esterified (E) and unesterified (UE) forms. Calculated ratios included UE:E for the five PUFA, ratios of n-3 PUFA (DHA:ALA, EPA:ALA, EPA:DHA), and the ratio of n-6:n-3 AA:EPA. Comparisons of plasma fatty acid levels and ratios between BD and HC groups were made with Student t-tests, between the BD group at baseline and follow-up using paired t-tests. Comparison of categorical variables was performed using Chi-square tests. Pearson’s r was used for bivariate correlations with clinical variables, including depressive and manic symptoms, current panic attacks, and psychosis. Results UE EPA was lower in BD than HC, with a large effect size (Cohen’s d = 0.86, p < 0.002), however, it was not statistically significant after correction for multiple comparisons. No statistically significant difference was seen in any plasma PUFA concentration between BD and HC after Bonferroni correction for 40 comparisons, at p < 0.001. Neither depressive severity nor mania severity was correlated significantly with any PUFA concentration. Exploratory comparison showed lower UE:E EPA in BD than HC (p < 0.0001). At follow-up in the BD group, UE, E DHA:ALA, and UE EPA:ALA were decreased (p < 0.002). Exploratory correlations of clinical variables revealed that mania severity and suicidality were positively correlated with UE:E EPA ratio, and that several plasma levels and ratios correlated with panic disorder and psychosis. Depressive severity was not correlated with any ratio. No plasma fatty acid level or ratio correlated with self-reported n-3 PUFA intake or use of medication by class. Conclusions A large effect size of reduced UE EPA, and a lower plasma UE:E concentration ratio of EPA in the symptomatic BD state may be an important factor in vulnerability to a mood state. Altered n-3 PUFA ratios could indicate changes in PUFA metabolism concurrent with symptom improvement. Our findings are consistent with preclinical and postmortem data and suggest testing interventions that increase n-3 and decrease n-6 dietary PUFA intake. PMID:26424416

Dish concentrators for solar thermal energy - Status and technology development

NASA Technical Reports Server (NTRS)

Jaffe, L. D.

1981-01-01

Comparisons are presented of point-focusing, or 'dish' solar concentrator system features, development status, and performance levels demonstrated to date. In addition to the requirements of good optical efficiency and high geometric concentration ratios, the most important future consideration in solar thermal energy dish concentrator design will be the reduction of installed and lifetime costs, as well as the materials and labor costs of production. It is determined that technology development initiatives are needed in such areas as optical materials, design wind speeds and wind loads, structural configuration and materials resistance to prolonged exposure, and the maintenance of optical surfaces. The testing of complete concentrator systems, with energy-converting receivers and controls, is also necessary. Both reflector and Fresnel lens concentrator systems are considered.

Isotretinoin kinetics after 80 to 320 mg oral doses.

PubMed

Colburn, W A; Gibson, D M

1985-04-01

Twelve healthy male subjects received 80, 160, 240, and 320 mg doses of oral isotretinoin as multiples of 40 mg capsules separated by 2-week washout periods in a randomized, crossover design. Blood samples were drawn at specific times over a 72-hour period after dosing. Blood concentrations of isotretinoin as well as its major metabolite, 4-oxo-isotretinoin, were determined by a specific HPLC method. In addition to the normal laboratory battery of tests, serum triglyceride levels were determined before the first dose and again 72 hours after each of the four doses. Mean (+/- SD) maximum concentrations after 80 to 320 mg doses were 366 +/- 159, 820 +/- 474, 1056 +/- 547, and 981 +/- 381 ng/ml, whereas the respective AUC0-infinity values were 3690 +/- 1280, 7030 +/- 4140, 9780 +/- 6080, and 9040 +/- 2900 ng X hr/ml. The observed apparent elimination t1/2 remained approximately the same (14.7 hours) for each dose. The maximum concentration and AUC values for isotretinoin appear to be dose proportional from 80 to 240 mg but plateau at the 320 mg dose level. Therefore, because isotretinoin blood concentrations may not increase with higher doses in the fasting state, single, oral doses in excess of 240 mg should be used with caution. The data also suggest that elevated triglyceride levels are not a simple function of isotretinoin blood concentrations across the entire study population and dose range studied, but that in subjects with triglyceride levels in excess of the normal range triglyceride levels were positively related to isotretinoin blood concentrations.

Prevalence of nucleic acid sequences specific for human parvoviruses, hepatitis A and hepatitis E viruses in coagulation factor concentrates.

PubMed

Modrow, S; Wenzel, J J; Schimanski, S; Schwarzbeck, J; Rothe, U; Oldenburg, J; Jilg, W; Eis-Hübinger, A M

2011-05-01

Due to their high resistance to inactivation procedures, nonenveloped viruses such as parvovirus B19, human bocavirus (HBoV), human parvovirus 4 (PARV4), hepatitis A (HAV) and hepatitis E virus (HEV) pose a particular threat to blood products. Virus transmission to patients treated with blood products presents an additional burden to disease. We determined the frequency and the amount of nucleic acid specific for nonenveloped viruses in recently manufactured preparations of commercial coagulation factor concentrates. At least three different batches of each of 13 different plasma-derived and recombinant coagulation factor products were tested for the presence and the amount of nucleic acid for parvovirus B19, HBoV, human parvovirus 4, hepatitis A virus and HEV by using quantitative polymerase chain reaction. Whereas none of the recombinant products tested positive for any of these viruses, parvovirus B19 DNA with amounts ranging between 2×10(1) and 1.3×10(3) genome equivalents/ml was detected in five plasma-derived products. In addition to parvovirus B19 genotype 1, genotypes 2 and 3 were observed in two batches of a factor VIII/von-Willebrand factor product. In two products (one factor VIII concentrate and one activated prothrombin complex concentrate), a combination of both genotypes 1 and 2 of parvovirus B19 was detected. The data show that nucleic acids from several relevant nonenveloped viruses are not found at detectable levels in coagulation factor concentrates. In some cases, parvovirus B19 DNA was detectable at low levels. Testing of the plasma pools for the full range of parvovirus genotypes is advocated for ensuring product safety. © 2010 The Author(s). Vox Sanguinis © 2010 International Society of Blood Transfusion.

[Key techniques for precision cultivation of nitrogenous fertilizer of pollution-free ginseng].

PubMed

Guo, Li-Li; Guo, Shuai; Dong, Lin-Lin; Shen, Liang; Li, Xi-Wen; Xu, Jiang; Chen, Shi-Lin

2018-04-01

Planting pollution-free farmland is the main mode of industrialization of ginseng cultivation, fine management of nitrogen fertilizer ginseng pollution-free farmland cultivation technology system is one of the key factors. In order to investigate the effect of nitrogenous fertilizer on the accumulation of ginseng biomass and saponins synthesis in vegetative growth stage, two-years-old ginsengs were used as test materials in this study. The test materials were cultivated by Hoagland medium with different nitrogen concentration (0，10，20，40 mg·L⁻¹) for 40 days. During the cultivation, photosynthetic rate was measured four times. After 40 days cultivation, chlorophyll content, stem diameter and the spatiotemporal expression of saponin synthesis related genes PgHMGR and PgSQE were tested. The results showed that there were significant differences in the photosynthetic rate and chlorophyll content among different nitrogen concentrations. The relative expression level of PgHMGR gene and PgSQE gene in root, stem and leaves of ginseng were different. Ginseng seedlings cultivated by 20 mg·L⁻¹ nitrogen possess the highest photosynthetic rate and chlorophyll content, while PgHMGR and PgSE showed the highest gene expression level. The optimal nitrogen concentration for the growth of 2-years-old ginseng might be 20 mg·L⁻¹ with 57.14 g ammonium nitrate each plant or pure 20.00 mg nitrogen each plant. It is concluded that this concentration is the most suitable concentration for the ginsenoside synthesis. Pollution-free ginseng with fine nitrogen fertilizer cultivation is conducive to the production of high quality and efficient ginseng medicinal materials. It lays a theoretical foundation for the rational fertilization and environment-friendly sustainable ecological ginseng planting industry. Copyright© by the Chinese Pharmaceutical Association.

Residues of chlortetracycline, doxycycline and sulfadiazine-trimethoprim in intestinal content and feces of pigs due to cross-contamination of feed.

PubMed

Peeters, Laura E J; Daeseleire, Els; Devreese, Mathias; Rasschaert, Geertrui; Smet, Annemieke; Dewulf, Jeroen; Heyndrickx, Marc; Imberechts, Hein; Haesebrouck, Freddy; Butaye, Patrick; Croubels, Siska

2016-09-20

Cross-contamination of feed with low concentrations of antimicrobials can occur at production, transport and/or farm level. Concerns are rising about possible effects of this contaminated feed on resistance selection in the intestinal microbiota. Therefore, an experiment with pigs was set up, in which intestinal and fecal concentrations of chlortetracycline (CTC), doxycycline (DOX) and sulfadiazine-trimethoprim (SDZ-TRIM) were determined after administration of feed containing a 3 % carry-over level of these antimicrobials. The poor oral bioavailability of tetracyclines resulted in rather high concentrations in cecal and colonic content and feces at steady-state conditions. A mean concentration of 10 mg/kg CTC and 4 mg/kg DOX in the feces was reached, which is higher than concentrations that were shown to cause resistance selection. On the other hand, lower mean levels of SDZ (0.7 mg/kg) and TRIM (< limit of detection of 0.016 mg/kg) were found in the feces, corresponding with the high oral bioavailability of SDZ and TRIM in pigs. The relation between the oral bioavailability and intestinal concentrations of the tested antimicrobials, may be of help in assessing the risks of cross-contaminated feed. However, future research is needed to confirm our results and to evaluate the effects of these detected concentrations on resistance selection in the intestinal microbiota of pigs.

Noninvasive Measurement of Steroid Hormones in Zebrafish Holding-Water

PubMed Central

Félix, Ana S.; Faustino, Ana I.; Cabral, Eduarda M.

2013-01-01

Abstract Zebrafish (Danio rerio) has recently emerged as a new animal model in neuroendocrinology and behavior (e.g., stress physiology and ecotoxicology studies). In these areas, the concentrations of steroid hormones in the blood are often used to study the endocrinological status of individuals. However, due to the small body size of zebrafish, blood sampling is difficult to perform and the amount of plasma obtained per sample for assaying hormones is very small (ca. 1–5 μL), and therefore most studies have been using whole-body hormone concentrations, which implies sacrificing the individuals and hampers sequential sampling of the same individual. Here a noninvasive method to assay steroid hormones from zebrafish holding-water, based on the fact that steroids are released into the fish holding-water through the gills by passive diffusion, is validated. Cortisol and the androgen 11-ketotestosterone (KT) were measured in water samples and compared to plasma levels in the same individuals. Cortisol released to holding-water correlates positively with plasma concentrations, but there was a lack of correlation between KT water and circulating levels. However, KT levels showed a highly significant sex difference that can be used to noninvasively sex individuals. An ACTH challenge test demonstrated that an induced increase in circulating cortisol concentration can be reliably detected in holding-water levels, hence attesting the responsiveness of holding-water levels to fluctuations in circulating levels. PMID:23445429

[Level of selected antibacterial tear proteins in children with diabetes type 1].

PubMed

Moll, Agnieszka; Wyka, Krystyna; Młynarski, Wojciech; Niwald, Anna

2011-01-01

Antibacterial immunity in diabetes is impaired, which increases the risk of general and local infections. The aim of the study was to evaluate non-specific local antibacterial immunity based on lactoferrin and lysozyme concentration in tears in children with diabetes type 1. Children at the age of 10-18 years old were studied. Group 1. consisted of children without diabetes, group 2. included patients with new onset of diabetes and group 3. consisted of children with decade-long diabetes. Among all patients tears were collected from inferior coniunctival fornix with hematocrit glass capillaries in purpose to measure lactoferrin and lysozyme concentration. ELISA method was used in laboratory testing. Level of lactoferrin did not differ significantly among all groups. Concentration of lysozyme was statistically lower in group with decade-long diabetes (group 3.) compared to patients without diabetes. Mild correlation between lactoferrin and lysozyme levels was seen in individual patients in whole group of probands together. Diabetes type 1 in children is associated with significant changes in concentration of tear proteins, which contribute to antibacterial immunity.

Distribution of volatile branched-chain fatty acids in various lamb tissues.

PubMed

Brennand, C P; Lindsay, R C

1992-01-01

Volatile fatty acids (C4-C11) including even-, odd-, and branched-chain members in lamb tissues were quantitatively analyzed. Volatile branched-chain fatty acids (BCFA) were more concentrated in subcutaneous adipose tissue samples (rump, shoulder, breast) than in perinepheric adipose or muscle tissues. Perinepheric adipose tissue contained relatively high quantities of n-chain, even-numbered fatty acids and very low levels of BCFA. Greater variation existed in fatty acid profiles among similar subcutaneous adipose tissues from different lambs than between samples of adipose tissue from different carcass sites from a given lamb sample. 4-Methyl- and 4-ethyloctanoic acids were present at concentrations greatly above threshold levels in all lamb fats tested, and thus upon hydrolysis would contribute species-related flavors to lamb. 4-Methylnonanoic concentrations in lamb fats ranged from nondetectable to greater than the threshold level, and therefore this compound would not always contribute to the species-related flavors of lamb. Lean meat samples contained very low concentrations of 4-methyl- and 4-ethyloctanoic acids. Copyright © 1992. Published by Elsevier Ltd.

Effects of metformin treatment on luteal phase progesterone concentration in polycystic ovary syndrome.

PubMed

Meenakumari, K J; Agarwal, S; Krishna, A; Pandey, L K

2004-11-01

The causes of luteal phase progesterone deficiency in polycystic ovary syndrome (PCOS) are not known. To determine the possible involvement of hyperinsulinemia in luteal phase progesterone deficiency in women with PCOS, we examined the relationship between progesterone, luteinizing hormone (LH) and insulin during the luteal phase and studied the effect of metformin on luteal progesterone levels in PCOS. Patients with PCOS (19 women aged 18-35 years) were treated with metformin (500 mg three times daily) for 4 weeks prior to the test cycle and throughout the study period, and submitted to ovulation induction with clomiphene citrate. Blood samples were collected from control (N = 5, same age range as PCOS women) and PCOS women during the late follicular (one sample) and luteal (3 samples) phases and LH, insulin and progesterone concentrations were determined. Results were analyzed by one-way analysis of variance (ANOVA), Duncan's test and Karl Pearson's coefficient of correlation (r). The endocrine study showed low progesterone level (4.9 ng/ml) during luteal phase in the PCOS women as compared with control (21.6 ng/ml). A significant negative correlation was observed between insulin and progesterone (r = -0.60; P < 0.01) and between progesterone and LH (r = -0.56; P < 0.05) concentrations, and a positive correlation (r = 0.83; P < 0.001) was observed between LH and insulin. The study further demonstrated a significant enhancement in luteal progesterone concentration (16.97 ng/ml) in PCOS women treated with metformin. The results suggest that hyperinsulinemia/insulin resistance may be responsible for low progesterone levels during the luteal phase in PCOS. The luteal progesterone level may be enhanced in PCOS by decreasing insulin secretion with metformin.

How does predation affect the bioaccumulation of hydrophobic organic compounds in aquatic organisms?

PubMed

Xia, Xinghui; Li, Husheng; Yang, Zhifeng; Zhang, Xiaotian; Wang, Haotian

2015-04-21

It is well-known that the body burden of hydrophobic organic compounds (HOCs) increases with the trophic level of aquatic organisms. However, the mechanism of HOC biomagnification is not fully understood. To fill this gap, this study investigated the effect of predation on the bioaccumulation of polycyclic aromatic hydrocarbons (PAHs), one type of HOC, in low-to-high aquatic trophic levels under constant freely dissolved PAH concentrations (1, 5, or 10 μg L(-1)) maintained by passive dosing systems. The tested PAHs included phenanthrene, anthracene, fluoranthene, and pyrene. The test organisms included zebrafish, which prey on Daphnia magna, and cichlids, which prey on zebrafish. The results revealed that for both zebrafish and cichlids, predation elevated the uptake and elimination rates of PAHs. The increase of uptake rate constant ranged from 20.8% to 39.4% in zebrafish with the amount of predation of 5 daphnids per fish per day, and the PAH uptake rate constant increased with the amount of predation. However, predation did not change the final bioaccumulation equilibrium; the equilibrium concentrations of PAHs in fish only depended on the freely dissolved concentration in water. Furthermore, the lipid-normalized water-based bioaccumulation factor of each PAH was constant for fish at different trophic levels. These findings infer that the final bioaccumulation equilibrium of PAHs is related to a partition between water and lipids in aquatic organisms, and predation between trophic levels does not change bioaccumulation equilibrium but bioaccumulation kinetics at stable freely dissolved PAH concentrations. This study suggests that if HOCs have not reached bioaccumulation equilibrium, biomagnification occurs due to enhanced uptake rates caused by predation in addition to higher lipid contents in higher trophic organisms. Otherwise, it is only due to the higher lipid contents in higher trophic organisms.

Influence of environmentally relevant concentrations of vinclozolin on quality, DNA integrity, and antioxidant responses of sterlet Acipenser ruthenus spermatozoa.

PubMed

Gazo, Ievgeniia; Linhartova, Pavla; Shaliutina, Anna; Hulak, Martin

2013-04-25

The effects of vinclozolin (VIN), an anti-androgenic fungicide, on quality, oxidative stress, DNA integrity, and ATP level of sterlet (Acipenser ruthenus) spermatozoa were investigated in vitro. Fish spermatozoa were incubated with different concentrations of vinclozolin (0.5, 2, 10, 15, 20 and 50 μg/l) for 2 h. A dose-dependent reduction in spermatozoa motility and velocity was observed at concentrations of 2-50 μg/l. A dramatic increase in DNA fragmentation was recorded at concentrations 10 μg/l and above. After 2 h exposure at higher test concentrations (10-50 μg/l), oxidative stress was apparent, as reflected by significantly higher levels of protein and lipid oxidation and significantly greater superoxide dismutase activity. Intracellular ATP content of spermatozoa decreased with increasing concentrations of VIN. The results demonstrated that VIN can induce reactive oxygen species stress in fish spermatozoa, which could impair the sperm quality, DNA integrity, ATP content, and the antioxidant defense system. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Influence of Aroclor 1242 concentration on polychlorinated biphenyl biotransformations in Hudson River test tube microcosms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fish, K.M.

1996-08-01

PCBs are a family of compounds sold with various levels of chlorination and under different trade names. They have accumulated in soils, sediments, and biota, raising concerns about possible health risks. The upper Hudson River was contaminated with Aroclor 1242. This study examines the influence of Aroclor concentration on PCB biotransformations in the upper Hudson River sediment. 6 refs., 3 figs.

Stress-induced changes in brain serotonergic activity, plasma cortisol and aggressive behavior in Arctic charr (Salvelinus alpinus) is counteracted by L-DOPA.

PubMed

Höglund, E; Kolm, N; Winberg, S

2001-10-01

Arctic charr (Salvelinus alpinus) were tested for aggressive behavior using intruder tests, before and after 2 days of dyadic social interaction. Following social interaction, half of the dominant and half of the subordinate fish were given L-DOPA (10 mg/kg, orally), whereas the remaining dominant and subordinate fish were given vehicle. One hour following drug treatment, the fish were tested for aggressive behavior again in a third and final intruder test, after which blood plasma and brain tissue were sampled for analysis of plasma cortisol concentrations and brain levels of monoamines and monoamine metabolites. Subordinate fish showed a reduction in the number of attacks launched against the intruder, as well as an increase in attack latency, as compared to prior to dyadic social interactions. Social subordination also resulted in an elevation of brain serotonergic activity. Fish receiving L-DOPA prior to the final intruder test showed shorter attack latency than vehicle controls. Drug treatment was a stressful experience and vehicle controls showed elevated plasma cortisol levels and longer attack latency as compared to before treatment. L-DOPA-treated fish showed lower plasma levels of cortisol and lower serotonergic activity in certain brain areas than vehicle controls. These results suggest that L-DOPA counteracts the stress-induced inhibition of aggressive behavior, and at the same time inhibits stress-induced effects on brain serotonergic activity and plasma cortisol concentrations.

A cross-sectional analysis of dioxins and health effects in municipal and private waste incinerator workers in Japan

PubMed Central

YAMAMOTO, Kenya; KUDO, Mitsuhiro; ARITO, Heihachiro; OGAWA, Yasutaka; TAKATA, Tsutomu

2015-01-01

This cross-sectional study was intended to examine health effects of 678 male workers employed during an 8-yr period from 2000 to 2007 at 36 municipal and private waste incineration plants in Japan. Blood samples were obtained for analysis of concentrations of dioxins including coplanar polychlorinated biphenyls (coplanar PCBs) and evaluation of health effects. Health effects including diabetes were surveyed via a physician’s interview or clinical data from blood samples. There was a certain difference in serum concentrations of polychlorinated dibenzofurans (PCDFs) between the incinerator workers and Japanese general population, although no differences in the concentrations of total dioxins or polychlorinated dibenzo-p-dioxins (PCDDs) were found between the two groups. A few positive correlations between serum levels of PCDDs and PCDFs and the results of laboratory and physiological tests were found, but coplanar PCBs showed significant relations with 14 parameters of the tests. The background serum levels of PCDDs, PCDFs and total dioxins were significantly associated with the prevalence of diabetes. No essential differences in serum concentrations of total dioxins and in prevalence of diabetes between our subjects and the general population suggested that the incinerator workers were marginally exposed to dioxins in the workplace without any recognizable adverse health effects. PMID:26212412

[Environmental toxicity of waste foundry sand].

PubMed

Zhang, Hai-Feng; Wang, Yu-Jue; Wang, Jin-Lin; Huang, Tian-You; Xiong, Ying

2013-03-01

The metal leaching characteristics and volatile organic compounds (VOCs) of five different types of waste foundry sands were analyzed with the toxicity characteristic leaching procedure (TCLP) and head space-gas chromatography (HS-GC). Microtox and soil dehydrogenase activity (DHA) tests were then used to evaluate the bio-effects of these waste sands. The results showed that due to the different metals poured and casting materials used to make the sand molds, there was significant difference among the five waste foundry sands in the compositions and concentrations of metal and organic pollutants. The concentrations of Fe in the leachates of iron and steel casting waste foundry sand exceeded the maximal allowable concentrations specified in the National Standard of Drinking Water Quality, whereas the As concentration in the leachate of aluminum casting waste foundry sand exceeded the standard. The five waste foundry sands had quite different compositions and levels of VOCs, which resulted in different levels of inhibition effects on the luminescent bacteria (30% and 95%). Additionally, the soil DHA tests suggested that metal pollutants in waste foundry sands may inhibit the soil microbial activity, whereas organics in the sands may slightly promote the microbial activity. The results of this study indicated that the waste foundry sands may pose considerable threat to the environment when improperly disposed.

Using Bioassays and Species Sensitivity Distributions to Assess Herbicide Toxicity towards Benthic Diatoms

PubMed Central

Larras, Floriane; Bouchez, Agnès; Rimet, Frédéric; Montuelle, Bernard

2012-01-01

Although benthic diatoms are widely used in ecological studies of aquatic systems, there is still a dearth of data concerning species sensitivities towards several contaminants. Within the same community, different species may respond differently depending on their physiological and ecological characteristics. This lack of knowledge makes specific appropriate risk assessment impossible. To find out whether species sensitivity distribution (SSD) could be used to estimate the risk of herbicide toxicity for diatoms, we need to know whether their sensitivity depends on their physiological and ecological characteristics. We carried out single-species bioassays on 11 diatom species exposed to 8 herbicides. Dose-responses relationships were used to extrapolate the Effective Concentration 5 (EC5) and the Effective Concentration 50 (EC50) for each exposure. These data were used to fit a SSD curve for each herbicide, and to determine the Hazardous concentration 5 (HC5) and 50 (HC50). Our results revealed a high level of variability of the sensitivity in the set of species tested. For photosystem-II inhibitor (PSII) herbicides, diatoms species displayed a typical grouping of sensitivity levels consistent with their trophic mode and their ecological guild. N-heterotroph and “motile” guild species were more tolerant of PSII inhibitors, while N-autotroph and “low profile” guild species were more sensitive. Comprehensive SSD curves were obtained for 5 herbicides, but not for sulfonylurea herbicides or for dimetachlor, which had toxicity levels that were below the range of concentration tested. The SSD curves provided the following ranking of toxicity: diuron> terbutryn> isoproturon> atrazine> metolachlor. The HC that affected 5% of the species revealed that, even at the usual environmental concentrations of herbicides, diatom assemblages could be affected, especially by isoproturon, terbutryn, and diuron. PMID:22952981

Preventive and curative effects of radon inhalation on chronic constriction injury-induced neuropathic pain in mice.

PubMed

Yamato, K; Kataoka, T; Nishiyama, Y; Taguchi, T; Yamaoka, K

2013-04-01

Radon therapy is clinically useful for the treatment of pain-related diseases. However, there have been no studies regarding the effects of radon inhalation on neuropathic pain. In this study, we aimed to determine whether radon inhalation actually induced a remission of neuropathic pain and improved the quality of life. First, we investigated the antinociceptive effects of radon inhalation in the chronic constriction injury (CCI) model of neuropathic pain. We evaluated pain behaviour in mice before and after CCI surgery, using von Frey test. Pretreated mice received CCI surgery immediately after 24-h inhalation of radon at background (BG) concentration (c. 19 Bq/m(3) ), or at a concentration of 1000 or 2000 Bq/m(3) , and post-treated mice inhaled similar levels of radon 2 days after CCI surgery. CCI surgery induced mechanical allodynia and hyperalgesia on a plantar surface of mice, as assessed using von Frey test, and 2000 Bq/m(3) radon inhalation alleviated hyperalgesic conditions 22-37% compared to BG level concentration. Concurrently, CCI surgery increased norepinephrine (NE), tumour necrosis factor-alpha (TNF-α) and nitric oxide (NO) concentrations in plasma, and leukocyte migration in paws. Furthermore, CCI-induced neuropathy reduced superoxide dismutase (SOD) activity. Treatment with radon inhalation, specifically at a concentration of 2000 Bq/m(3) , produced antinociceptive effects, i.e., lowered plasma TNF-α, NE and NO levels and restored SOD activity, as well as pain-related behaviour. This study showed that inhalation of 2000 Bq/m(3) radon prevented and alleviated CCI-induced neuropathic pain in mice. © 2012 European Federation of International Association for the Study of Pain Chapters.

Improving in vitro to in vivo extrapolation by incorporating toxicokinetic measurements: A case study of lindane-induced neurotoxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Croom, Edward L.; Shafer, Timothy J.; Evans, Marina V.

Approaches for extrapolating in vitro toxicity testing results for prediction of human in vivo outcomes are needed. The purpose of this case study was to employ in vitro toxicokinetics and PBPK modeling to perform in vitro to in vivo extrapolation (IVIVE) of lindane neurotoxicity. Lindane cell and media concentrations in vitro, together with in vitro concentration-response data for lindane effects on neuronal network firing rates, were compared to in vivo data and model simulations as an exercise in extrapolation for chemical-induced neurotoxicity in rodents and humans. Time- and concentration-dependent lindane dosimetry was determined in primary cultures of rat cortical neuronsmore » in vitro using “faux” (without electrodes) microelectrode arrays (MEAs). In vivo data were derived from literature values, and physiologically based pharmacokinetic (PBPK) modeling was used to extrapolate from rat to human. The previously determined EC{sub 50} for increased firing rates in primary cultures of cortical neurons was 0.6 μg/ml. Media and cell lindane concentrations at the EC{sub 50} were 0.4 μg/ml and 7.1 μg/ml, respectively, and cellular lindane accumulation was time- and concentration-dependent. Rat blood and brain lindane levels during seizures were 1.7–1.9 μg/ml and 5–11 μg/ml, respectively. Brain lindane levels associated with seizures in rats and those predicted for humans (average = 7 μg/ml) by PBPK modeling were very similar to in vitro concentrations detected in cortical cells at the EC{sub 50} dose. PBPK model predictions matched literature data and timing. These findings indicate that in vitro MEA results are predictive of in vivo responses to lindane and demonstrate a successful modeling approach for IVIVE of rat and human neurotoxicity. - Highlights: • In vitro to in vivo extrapolation for lindane neurotoxicity was performed. • Dosimetry of lindane in a micro-electrode array (MEA) test system was assessed. • Cell concentrations at the MEA EC{sub 50} equaled rat brain levels associated with seizure. • PBPK-predicted human brain levels at seizure also equaled EC{sub 50} cell concentrations. • In vitro MEA results are predictive of lindane in vivo dose–response in rats/humans.« less

ProUCL Version 4.0 Technical Guide

EPA Science Inventory

Statistical inference, including both estimation and hypotheses testing approaches, is routinely used to: estimate environmental parameters of interest, such as exposure point concentration (EPC) terms, not-to-exceed values, and background level threshold values (BTVs) for contam...

Controlling the fluoride dosage in a patient with compromised salivary function.

PubMed

Eichmiller, Frederick C; Eidelman, Naomi; Carey, Clifton M

2005-01-01

High-concentration topical fluorides are used commonly to with compromised salivary function due to irradiation and chemotherapy. The authors describe a 50-year-old man with previously treated cancer who was using tray-applied topical fluoride gel. He complained of gastric symptoms, difficulty in swallowing, leg muscle soreness and knee joint soreness. A computed tomographic scan revealed thickening of the esophageal walls. An upper endoscopy revealed abnormal motility. The motility test indicated high-amplitude peristalsis and hypertensive lower esophageal sphincter, and urine testing indicated high levels of systemic fluoride. The patient's fluoride regimen was altered, and within a short period his urinary fluoride levels returned to normal and his symptoms resolved. Clinicians prescribing home-applied high-concentration fluorides need to be cognizant of the symptoms of fluoride toxicity, carefully monitor the patient's compliance with the treatment regimen, and adjust the dosage or mode of application to control the total ingested dose of fluoride.

Mercury in aqueous tank waste at the Savannah River Site: Facts, forms, and impacts

DOE PAGES

Bannochie, C. J.; Fellinger, T. L.; Garcia-Strickland, P.; ...

2017-03-28

Over the past two years, there has been an intense effort to understand the chemistry of mercury across the Savannah River Site’s high-level liquid waste system to determine the impacts of various mercury species. This effort started after high concentrations of mercury were measured in the leachates from a toxicity characteristic leaching procedure (TCLP) test on the low-level cementitious waste form produced in the Savannah River Saltstone facility. Speciation showed the dominant form of leached mercury to be the methylmercury cation. Neither the source of the methylmercury nor its concentration in the Saltstone feed was well established at the timemore » of the testing. Finally, this assessment of mercury was necessary to inform points in the process operations that may be subject to new separation technologies for the removal of mercury.« less

Mercury in aqueous tank waste at the Savannah River Site: Facts, forms, and impacts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bannochie, C. J.; Fellinger, T. L.; Garcia-Strickland, P.

Over the past two years, there has been an intense effort to understand the chemistry of mercury across the Savannah River Site’s high-level liquid waste system to determine the impacts of various mercury species. This effort started after high concentrations of mercury were measured in the leachates from a toxicity characteristic leaching procedure (TCLP) test on the low-level cementitious waste form produced in the Savannah River Saltstone facility. Speciation showed the dominant form of leached mercury to be the methylmercury cation. Neither the source of the methylmercury nor its concentration in the Saltstone feed was well established at the timemore » of the testing. Finally, this assessment of mercury was necessary to inform points in the process operations that may be subject to new separation technologies for the removal of mercury.« less

Iodine Systematics in the Ground Water of a Natural Setting

NASA Astrophysics Data System (ADS)

Renaud, R.; Clark, I. D.; Kotzer, T.; Bottomley, D.

2001-12-01

The transport and partitioning of 129I has been examined for a shallowly circulating ground water system at Sturgeon Falls in eastern Ontario. Vertical recharge occurs in a sandy aquifer with a seasonally inundated boreal forest. Concentrations of stable iodine, 129I, and tritium were measured on samples of ground water, precipitation, and soil litter. The present-day tritium profile delineates the position of the early 1960's thermonuclear bomb-pulse at a depth approximately 12 m. The concentrations of stable iodine for ground waters above, near and below the present-day bomb pulse were largely invariant, at approximately 0.5 ppb, whereas 129I concentrations decreased from 1.9 x 106 atoms/L at 9 m, to approximately 1.9 x 105 atoms/L on tritium-depleted waters occurring below the present-day location of the recharging thermonuclear bomb-test peak at 35 m. No substantial increases in the levels of 129I were evident in waters sampled near the present-day location of the thermonuclear bomb peak. Along a 30 cm soil profile, the concentrations of 129I ranged from approximately 4.3 x 108 atoms/g in the uppermost soil litter layer to 5.6 x 107 atoms/g in the siltier bottom soil horizons. Over that same profile, stable iodine varied from 4.7 ppm in the upper layers to 3.9 ppm in the lower layers. Rao and Fehn, 1999, measured iodine and 129I levels in surface waters and soils in western New York. They found 129I concentrations ranging from 3.5 x 108 atoms/g to 7.1 x 1010 atoms/g in the upper most layers of their soil cores, depending on the site's proximity to a former nuclear fuel reprocessing plant. Similarly, they noticed that the lower layers of their soil cores had 129I concentrations of at least an order of magnitude lower than the upper layers. It is proposed here that the levels of 129I in the deepest, tritium-depleted ground waters reflect the concentrations of 129I during the pre-thermonuclear testing period. However, the lower concentrations of 129I at Sturgeon Falls, compared with those from other studies in central Canada, suggest that the levels of 129I in these ground waters may have been attenuated by ion-exchange with organic materials in the near-surface soil horizons. Such processes have been documented during a previous study on the behavior of 129I in a shallow aquifer near a low-level, radioactive waste management area.

Pulmonary exposure to cellulose nanocrystals caused deleterious effects to reproductive system in male mice

PubMed Central

Farcas, Mariana T.; Kisin, Elena R.; Menas, Autumn L.; Gutkin, Dmitriy W.; Star, Alexander; Reiner, Richard S.; Yanamala, Naveena; Savolainen, Kai; Shvedova, Anna A.

2016-01-01

Over the past several years there has been an increased number of applications of cellulosic materials in many sectors, including the food industry, cosmetics, and pharmaceuticals. However, to date, there are few studies investigating the potential adverse effects of cellulose nanocrystals (CNC). The objective of this study was to determine long-term outcomes on the male reproductive system of mice upon repeated pharyngeal aspiration exposure to CNC. To achieve this, cauda epididymal sperm samples were analyzed for sperm concentration, motility, morphological abnormalities, and DNA damage. Testicular and epididymal oxidative damage was evaluated, as well as histopathology examination of testes. In addition, changes in levels of testosterone in testes and serum and of luteinizing hormone (LH) in serum were determined. Three months after the last administration, CNC exposure significantly altered sperm concentration, motility, cell morphology, and sperm DNA integrity. These parameters correlated with elevated proinflammatory cytokines levels and myeloperoxidase (MPO) activity in testes, as well as oxidative stress in both testes and epididymis. Exposure to CNC also produced damage to testicular structure, as evidenced by presence of interstitial edema, frequent dystrophic seminiferous tubules with arrested spermatogenesis and degenerating spermatocytes, and imbalance in levels of testosterone and LH. Taken together, these results demonstrate that pulmonary exposure to CNC induces sustained adverse effects in spermatocytes/spermatozoa, suggesting male reproductive toxicity. PMID:27558875

Isolation of parafluorophenylalanine-resistant mutants from HeLa cell cultures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yim, L.K.; Stuart, W.D.

This report describes a method to isolate temperature-conditional phenylalanine transport mutants from the transformed human cell line HeLa. Using ultraviolet light as a mutagenic agent and DL-parafluorophenylalanine (PFPA), a poisonous analogue of L-phenylalanine, as a selective agent, mutagenized cells were selected for survival in the presence of PFPA at a temperature of 39 degrees C. Survivors of the mutagenesis and selection procedures were removed from the culture dishes by trypsin and cloned at a temperature of 35 degrees C. Seven of these lines isolated demonstrated continued resistance to PFPA at 39 degrees C. These lines were tested for uptake ofmore » L-phenylalanine at an external concentration of 100 microM and for continued resistance to PFPA at two concentrations. Cells were tested at 35 and at 39 degrees C. The data were compared to those obtained for the parental HeLa cell line under identical conditions. The seven mutant cell lines demonstrated varying resistances to PFPA and varying levels of accumulation of L-phenylalanine when tested at 35 and 39 degrees C. Three mutant lines were additionally tested for L-phenylalanine tRNA charging levels and for transport of L-arginine. The lines had parental cell levels of tRNA charging and L-arginine transport which suggest that the induced genetic defect affects a specific L-phenylalanine transport system.« less

Effect of active tuberculosis on skin prick allergy tests and serum IgE levels.

PubMed

Kutlu, A; Bozkanat, E; Ciftçi, Fi; Bozkurt, B; Gorur, R; Ardiç, N; Taskapan, O

2008-01-01

Mycobacterium tuberculosis has been shown to suppress allergic airway disease driven by type 2 helper T cells in animal models. In this study, we investigated the effect of active tuberculosis on skin prick test (SPT) positivity and serum immunoglobulin (Ig) E levels of atopic patients with and without tuberculosis infection. Seventeen atopic HIV-negative men with pulmonary tuberculosis and 18 atopic healthy male controls at our military hospital were studied prospectively between March 2005 and March 2006. The sums of all SPT positive tests and positivity to house dust mite alone were calculated before initiation of treatment and after 6 months. Measurement of total serum IgE levels was also performed at the same moments. The mean (SD) initial serum total IgE concentrations were significantly higher in the tuberculosis patients than in the healthy controls (324.1 [317.67] U/mL vs. 146.7 [75.29] U/mL, respectively; P < .05), The total serum IgE concentrations after 6 months of treatment were also higher in the patients than in the controls. The mean sum of SPT positivity was higher in the tuberculosis patients than in the controls at both testing times. Our study does not support the hypothesis that M tuberculosis suppresses atopy and atopic disorders, but large, prospective experimental studies are needed before excluding the possibility of a relationship.

Radon Assessment of Occupational Facilities, Homestead ARB, FL

DTIC Science & Technology

2013-11-21

electrets is directly measured and used to calculate radon levels. The radon detectors were placed in the test locations for greater than 90 days in...of USAFSAM’s radon analysis. A proficiency test was last performed and passed on 18 July 2012. (2) Blanks: Six field blanks were used during the...voltage. 5. CONCLUSIONS AND RECOMMENDATIONS: a. All 46 facilities tested had radon concentrations below the action limit of 4 pCi/L; no radon

The Statistical Value of Raw Fluorescence Signal in Luminex xMAP Based Multiplex Immunoassays

PubMed Central

Breen, Edmond J.; Tan, Woei; Khan, Alamgir

2016-01-01

Tissue samples (plasma, saliva, serum or urine) from 169 patients classified as either normal or having one of seven possible diseases are analysed across three 96-well plates for the presences of 37 analytes using cytokine inflammation multiplexed immunoassay panels. Censoring for concentration data caused problems for analysis of the low abundant analytes. Using fluorescence analysis over concentration based analysis allowed analysis of these low abundant analytes. Mixed-effects analysis on the resulting fluorescence and concentration responses reveals a combination of censoring and mapping the fluorescence responses to concentration values, through a 5PL curve, changed observed analyte concentrations. Simulation verifies this, by showing a dependence on the mean florescence response and its distribution on the observed analyte concentration levels. Differences from normality, in the fluorescence responses, can lead to differences in concentration estimates and unreliable probabilities for treatment effects. It is seen that when fluorescence responses are normally distributed, probabilities of treatment effects for fluorescence based t-tests has greater statistical power than the same probabilities from concentration based t-tests. We add evidence that the fluorescence response, unlike concentration values, doesn’t require censoring and we show with respect to differential analysis on the fluorescence responses that background correction is not required. PMID:27243383

Alpha-fetoprotein and its value for predicting pregnancy outcomes – a re-evaluation

PubMed Central

Darouich, Ayham Alhaj; Liehr, Thomas; Weise, Anja; Schlembach, Dietmar; Schleußner, Ekkehart; Kiehntopf, Michael; Schreyer, Isolde

2015-01-01

Introduction Alpha-fetoprotein (AFP) concentrations can be determined framing others from invasively acquired amnion fluid (AF-AFP). While the biological role of AFP remains unclear it is well known that AFP-levels can be altered in connection with specific clinical and/or genetic alterations of the fetus. Materials and Method here a retrospective study based on 3,119 singleton and 56 twin pregnancies is presented. The standard levels of amnion fluid derived alpha-fetoprotein level (AF-AFP) between 12th and 36th weeks of gestation were determined. Additionally, acetylcholinesterase (AChE) test results for 63 cases, ultrasonography results for 32 cases and abnormal karyotypic findings for 100 cases were available for selected cases. Results and Discussion according to the present data the AF-AFP test is reliable and provides expected test results in terms of population studies. However, individual AF-AFP test results can be subject to high individual variations. In this study AF-AFP multiple of medians (MoM) over 1.7 were indicative for neuronal tube defects and/or omphalocele in only 6.3% of the cases, while such AF-AFP values were hints on severe sonographic signs in 62% of the cases. Also, altered AF-AFP concentrations were present in 82% of cytogenetically abnormal cases. Overall, even though predicative value of the AF-AFP-test is matter of discussion it continues to be widely applied in invasive prenatal diagnostics. This study indicates that it only can be applied reliably in combination with other tests like banding cytogenetics, ultrasonography and all embedded in well-established genetic counseling. PMID:27358693

Cross-sectional and longitudinal relationships between cerebrospinal fluid biomarkers and cognitive function in people without cognitive impairment from across the adult life span.

PubMed

Li, Ge; Millard, Steven P; Peskind, Elaine R; Zhang, Jing; Yu, Chang-En; Leverenz, James B; Mayer, Cynthia; Shofer, Jane S; Raskind, Murray A; Quinn, Joseph F; Galasko, Douglas R; Montine, Thomas J

2014-06-01

Age-related cognitive decline among older individuals with normal cognition is a complex trait that potentially derives from processes of aging, inherited vulnerabilities, environmental factors, and common latent diseases that can progress to cause dementia, such as Alzheimer disease and vascular brain injury. To use cerebrospinal fluid (CSF) biomarkers to gain insight into this complex trait. Secondary analyses of an academic multicenter cross-sectional (n = 315) and longitudinal (n = 158) study of 5 neuropsychological tests (Immediate Recall, Delayed Recall, Trail Making Test Parts A and B, and Category Fluency) in cognitively normal individuals aged 21 to 100 years. To investigate the association of these cognitive function test results with age, sex, educational level, inheritance of the ε4 allele of the apolipoprotein E gene, and CSF concentrations of β-amyloid 42 (Aβ42) and tau (biomarkers of Alzheimer disease) as well as F2-isoprostanes (measures of free radical injury). Age and educational level were broadly predictive of cross-sectional cognitive performance; of the genetic and CSF measures, only greater CSF F2-isoprostane concentration was significantly associated with poorer executive function (adjusted R2 ≤0.31). Longitudinal measures of cognitive abilities, except Category Fluency, also were associated broadly with age; of the genetic and CSF measures, only lower baseline CSF Aβ42 concentration was associated with longitudinal measures of immediate and delayed recall (marginal R2 ≤0.31). Our results suggest that age and educational level accounted for a substantial minority of variance in cross-sectional or longitudinal cognitive test performance in this large group of cognitively normal adults. Latent Alzheimer disease and other diseases that produce free radical injury, such as vascular brain injury, accounted for a small amount of variation in cognitive test performance across the adult human life span. Additional genetic and environmental factors likely contribute substantially to age-related cognitive decline.

Physical Performance and Serum 25(OH)vitamin D Status in Community Dwelling Old Mobility Limited Adults: A Cross-Sectional Study.

PubMed

von Berens, Å; Cederholm, T; Fielding, R A; Gustafsson, T; Kirn, D; Laussen, J; Nydahl, M; Travison, T G; Reid, K; Koochek, A

2018-01-01

To examine the potential association between serum 25(OH) vitamin D and the performance on the Short Physical Performance Battery (SPPB) including the sub-components; five repeated chair stands test, 4 meters walk test and balance in older mobility-limited community-dwelling men and women. A cross sectional study was performed in American and Swedish subjects who were examined for potential participation in a combined exercise and nutrition intervention trial. Logistic regression analysis and linear regression analyses were performed to evaluate the association for 25(OH)D with the overall score on the SBBP, chair stand, gait speed and balance. Community-dwelling (mean age 77.6 ± 5.3 years) mobility limited American (n=494) and Swedish (n=116) females (59%) and males. The SPPB (0-12 points) includes chair stand (s), gait speed (m/s) and a balance test. Mobility limitation i.e., SPPB score ≤ 9 was an inclusion criterion. A blood sample was obtained to measure serum 25(OH)vitamin D concentrations. No clear association of 25(OH)D with SPPB scores was detected either when 25(OH)D was assessed as a continuous variable or when categorized according to serum concentrations of <50, 50-75 or <75 nmol/L. However, when analyzing the relationship between 25(OH)D and seconds to perform the chair stands, a significant quadratic relationship was observed. Thus, at serum levels of 25(OH)D above 74 nmol/L, higher concentrations appeared to be advantageous for the chair stand test, whereas for serum levels below 74 nmol/L this association was not observed. This cross- sectional study lacked clear association between serum 25(OH)D and physical performance in mobility limited adults. A potentially interesting observation was that at higher serum levels of 25(OH)D a better performance on the chair stand test was indicated.

A comprehensive evaluation of the toxicology of cigarette ingredients: carbohydrates and natural products.

PubMed

Coggins, Christopher R E; Wagner, Karl A; Werley, Michael S; Oldham, Michael J

2011-06-01

Eleven carbohydrates and natural product ingredients were added individually to experimental cigarettes. A battery of tests was used to compare toxicity of mainstream smoke from these experimental cigarettes to matched control cigarettes without test ingredients. Smoke fractions from each cigarette type were evaluated using analytical chemistry; in vitro cytotoxicity (neutral red uptake) and in vitro bacterial (Salmonella) mutagenicity (five strains) testing. For 10 ingredients (β-cyclodextrin, cleargum, D-sorbitol, high fructose corn syrup, honey, invert sugar, maltodextrin, molasses, raisin juice concentrate, and sucrose), 90-day nose-only smoke inhalation studies using rats were also performed. In general, addition of each ingredient in experimental cigarettes resulted in minimal changes in smoke chemistry; the exceptions were D-sorbitol and sucrose, where reductions in amount of 60% to 80% of control values for some smoke constituents were noted. Additionally, each ingredient resulted in small increases in smoke formaldehyde concentrations. Except for a reduction in cytotoxicity by inclusion of maltodextrin and an increase by inclusion of plum juice concentrate, the cytotoxicity and mutagenicity results were unaffected by addition of the other ingredients in experimental cigarettes. There were also very few statistically significant differences within any of the 10 inhalation studies, and when present, the differences were largely sporadic and inconsistent between sexes. The carbohydrates and natural products tested here as ingredients in experimental cigarettes as a class increased formaldehyde, but resulted in minimal toxicological responses, even at high inclusion levels compared with the levels used in commercial cigarette products.

Development of a simulated earthworm gut for determining bioaccessible arsenic, copper, and zinc from soil.

PubMed

Ma, Wai K; Smith, Ben A; Stephenson, Gladys L; Siciliano, Steven D

2009-07-01

Soil physicochemical characteristics and contamination levels alter the bioavailability of metals to terrestrial invertebrates. Current laboratory-derived benchmark concentrations used to estimate risk do not take into account site-specific conditions, such as contaminant sequestration, and site-specific risk assessment requires a battery of time-consuming and costly toxicity tests. The development of an in vitro simulator for earthworm bioaccessibility would significantly shorten analytical time and enable site managers to focus on areas of greatest concern. The simulated earthworm gut (SEG) was developed to measure the bioaccessibility of metals in soil to earthworms by mimicking the gastrointestinal fluid composition of earthworms. Three formulations of the SEG (enzymes, microbial culture, enzymes and microbial culture) were developed and used to digest field soils from a former industrial site with varying physicochemical characteristics and contamination levels. Formulations containing enzymes released between two to 10 times more arsenic, copper, and zinc from contaminated soils compared with control and 0.01 M CaCl2 extractions. Metal concentrations in extracts from SEG formulation with microbial culture alone were not different from values for chemical extractions. The mechanism for greater bioaccessible metal concentrations from enzyme-treated soils is uncertain, but it is postulated that enzymatic digestion of soil organic matter might release sequestered metal. The relevance of these SEG results will need validation through further comparison and correlation with bioaccumulation tests, alternative chemical extraction tests, and a battery of chronic toxicity tests with invertebrates and plants.

Evaluation of retrofit crankcase ventilation controls and diesel oxidation catalysts for reducing air pollution in school buses

NASA Astrophysics Data System (ADS)

Trenbath, Kim; Hannigan, Michael P.; Milford, Jana B.

2009-12-01

This study evaluates the effect of retrofit closed crankcase ventilation filters (CCFs) and diesel oxidation catalysts (DOCs) on the in-cabin air quality in transit-style diesel school buses. In-cabin pollution levels were measured on three buses from the Pueblo, CO District 70 fleet. Monitoring was conducted while buses were driven along their regular routes, with each bus tested three times before and three times after installation of control devices. Ultrafine number concentrations in the school bus cabins were 33-41% lower, on average, after the control devices were installed. Mean mass concentrations of particulate matter less than 2.5 μm in diameter (PM2.5) were 56% lower, organic carbon (OC) 41% lower, elemental carbon (EC) 85% lower, and formaldehyde 32% lower after control devices were installed. While carbon monoxide concentrations were low in all tests, mean concentrations were higher after control devices were installed than in pre-retrofit tests. Reductions in number, OC, and formaldehyde concentrations were statistically significant, but reductions in PM2.5 mass were not. Even with control devices installed, during some runs PM2.5 and OC concentrations in the bus cabins were elevated compared to ambient concentrations observed in the area. OC concentrations inside the bus cabins ranged from 22 to 58 μg m -3 before and 13 to 33 μg m -3 after control devices were installed. OC concentrations were correlated with particle-bound organic tracers for lubricating oil emissions (hopanes) and diesel fuel and tailpipe emissions (polycyclic aromatic hydrocarbons (PAH) and aliphatic hydrocarbons). Mean concentrations of hopanes, PAH, and aliphatic hydrocarbons were lower by 37, 50, and 43%, respectively, after the control devices were installed, suggesting that both CCFs and DOCs were effective at reducing in-cabin OC concentrations.

Chemical characteristics of urban stormwater sediments and implications for environmental management, Maricopa County, Arizona

USGS Publications Warehouse

Parker, J.T.C.; Fossum, K.D.; Ingersoll, T.L.

2000-01-01

Investigations of the chemical characteristics of urban stormwater sediments in the rapidly growing Phoenix metropolitan area of Maricopa County, Arizona, showed that the inorganic component of these sediments generally reflects geologic background values. Some concentrations of metals were above background values, especially cadmium, copper, lead, and zinc, indicating an anthropogenic contribution of these elements to the sediment chemistry. Concentrations, however, were not at levels that would require soil remediation according to guidelines of the U.S. Environmental Protection Agency. Arsenic concentrations generally were above recommended values for remediation at a few sites, but these concentrations seem to reflect geologic rather than anthropogenic factors. Several organochlorine compounds no longer in use were ubiquitous in the Phoenix area, although concentrations generally were low. Chlordane, DDT and its decay products DDE and DDD, dieldrin, toxaphene, and PCBs were found at almost all sites sampled, although some of the pesticides in which these compounds are found have been banned for almost 30 years. A few sites showed exceptionally high concentrations of organochlorine compounds. On the basis of published guidelines, urban stormwater sediments do not appear to constitute a major regional environmental problem with respect to the chemical characteristics investigated here. At individual sites, high concentrations of organic compounds - chlordane, dieldrin, PCBs, and toxaphene - may require some attention. The possible environmental hazard presented by low-level organochlorine contamination is not addressed in this paper; however, high levels of toxicity in urban sediments are difficult to explain. Sediment toxicity varied significantly with time, which indicates that these tests should be evaluated carefully before they are used for management decisions.Investigations of the chemical characteristics of urban stormwater sediments in the rapidly growing Phoenix metropolitan area of Maricopa County, Arizona, showed that the inorganic component of these sediments generally reflects geologic background values. Some concentrations of metals were above background values, especially cadmium, copper, lead, and zinc, indicating an anthropogenic contribution of these elements to the sediment chemistry. Concentrations, however, were not at levels that would require soil remediation according to guidelines of the U.S. Environmental Protection Agency. Arsenic concentrations generally were above recommended values for remediation at a few sites, but these concentrations seem to reflect geologic rather than anthropogenic factors. Several organochlorine compounds no longer in use were ubiquitous in the Phoenix area, although concentrations generally were low. Chlordane, DDT and its decay products DDE and DDD, dieldrin, toxaphene, and PCBs were found at almost all sites sampled, although some of the pesticides in which these compounds are found have been banned for almost 30 years. A few sites showed exceptionally high concentrations of organochlorine compounds. On the basis of published guidelines, urban stormwater sediments do not appear to constitute a major regional environmental problem with respect to the chemical characteristics investigated here. At individual sites, high concentrations of organic compounds - chlordane, dieldrin, PCBs, and toxaphene - may require some attention. The possible environmental hazard presented by low-level organochlorine contamination is not addressed in this paper; however, high levels of toxicity in urban sediments are difficult to explain. Sediment toxicity varied significantly with time, which indicates that these tests should be evaluated carefully before they are used for management decisions.

Effect of stress concentration on the fatigue strength of A7N01S-T5 welded joints

NASA Astrophysics Data System (ADS)

Zhang, Mingyue; Gou, Guoqing; Hang, Zongqiu; Chen, Hui

2017-07-01

Stress concentration is a key factor that affects the fatigue strength of welded joints. In this study, the fatigue strengths of butt joints with and without the weld reinforcement were tested to quantify the effect of stress concentration. The fatigue strength of the welded joints was measured with a high-frequency fatigue machine. The P-S-N curves were drawn under different confidence levels and failure probabilities. The results show that butt joints with the weld reinforcement have much lower fatigue strength than joints without the weld reinforcement. Therefore, stress concentration introduced by the weld reinforcement should be controlled.

E-4 Test Facility Design Status

NASA Technical Reports Server (NTRS)

Ryan, Harry; Canady, Randy; Sewell, Dale; Rahman, Shamim; Gilbrech, Rick

2001-01-01

Combined-cycle propulsion technology is a strong candidate for meeting NASA space transportation goals. Extensive ground testing of integrated air-breathing/rocket system (e.g., components, subsystems and engine systems) across all propulsion operational modes (e.g., ramjet, scramjet) will be needed to demonstrate this propulsion technology. Ground testing will occur at various test centers based on each center's expertise. Testing at the NASA John C. Stennis Space Center will be primarily concentrated on combined-cycle power pack and engine systems at sea level conditions at a dedicated test facility, E-4. This paper highlights the status of the SSC E-4 test Facility design.

Toxicity of the pyrolysis products of spacecraft materials

NASA Technical Reports Server (NTRS)

Lawrence, W. H.

1974-01-01

A number of spacecraft construction materials are evaluated for the toxic effects of their thermodegradation products on rats. Pyrolysis toxicity testing of pyrolysate fumes establish carbon monoxide, carbon dioxide and hydrogen cyanide as the most common intoxicating agents. Generally, COHb levels of animals expiring in the test chamber suggest higher concentrations of CO are produced with larger samples of most materials.

Dimethadione embryotoxicity in the rat is neither correlated with maternal systemic drug concentrations nor embryonic tissue levels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ozolinš, Terence R.S., E-mail: ozolinst@queensu.ca; Weston, Andrea D.; Perretta, Anthony

Pregnant rats treated with dimethadione (DMO), the N-demethylated metabolite of the anticonvulsant trimethadione, produce offspring having a 74% incidence of congenital heart defects (CHD); however, the incidence of CHD has high inter-litter variability (40–100%) that presents a challenge when studying the initiating events prior to the presentation of an abnormal phenotype. We hypothesized that the variability in CHD incidence was the result of differences in maternal systemic concentrations or embryonic tissue concentrations of DMO. To test this hypothesis, dams were administered 300 mg/kg DMO every 12 h from the evening of gestational day (GD) 8 until the morning of GDmore » 11 (six total doses). Maternal serum levels of DMO were assessed on GD 11, 12, 13, 14, 15, 18 and 21. Embryonic tissue concentrations of DMO were assessed on GD 11, 12, 13 and 14. In a separate cohort of GD 12 embryos, DMO concentrations and parameters of growth and development were assessed to determine if tissue levels of DMO were correlated with these endpoints. Embryos were exposed directly to different concentrations of DMO with whole embryo culture (WEC) and their growth and development assessed. Key findings were that neither maternal systemic concentrations nor tissue concentrations of DMO identified embryos that were sensitive or resistant to DMO in vivo. Direct exposure of embryos to DMO via WEC also failed to show correlations between embryonic concentrations of DMO with developmental outcomes in vitro. We conclude that neither maternal serum nor embryonic tissue concentrations of DMO predict embryonic outcome. - Highlights: • Dimethadione (DMO) induces septation defects (VSD) in rat offspring. • Despite high rate of VSD defects inter-litter variability is 40–100%. • Maternal and embryonic concentrations of DMO were assessed. • Neither serum nor tissue levels of DMO were correlated with embryotoxicity.« less

2011 Groundwater Monitoring and Inspection Report Gnome-Coach Site, New Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2012-02-01

Gnome-Coach was the site of a 3-kiloton underground nuclear test in 1961. Surface and subsurface contamination resulted from the underground nuclear testing, post-test drilling, and groundwater tracer test performed at the site. The State of New Mexico is currently proceeding with a conditional certificate of completion for the surface. As for the subsurface, monitoring activities that include hydraulic head monitoring and groundwater sampling of the wells onsite are conducted as part of the annual site inspection. These activities were conducted on January 19, 2011. The site roads, monitoring well heads, and the monument at surface ground zero were observed asmore » being in good condition at the time of the site inspection. An evaluation of the hydraulic head data obtained from the site indicates that water levels in wells USGS-4 and USGS-8 appear to respond to the on/off cycling of the dedicated pump in well USGS-1 and that water levels in wells LRL-7 and DD-1 increased during this annual monitoring period. Analytical results obtained from the sampling indicate that concentrations of tritium, strontium-90, and cesium-137 were consistent with concentrations from historical sampling events.« less

Overview and comparison of lipid-containing semipermeable membrane devices and oysters (Crassostrea gigas) for assessing organic chemical exposure

USGS Publications Warehouse

Huckins, J.N.; Prest, H.F.; Petty, J.D.; Lebo, J.A.; Hodgins, M.M.; Clark, R.C.; Alvarez, D.A.; Gala, W.R.; Steen, A.; Gale, R.; Ingersoll, C.G.

2004-01-01

We performed 20-d, flow-through exposures of lipid-containing semipermeable membrane devices (SPMDs) and Pacific oysters (Crassostrea gigas) to three concentrations (nominally 10, 100, and 250 ng/L) of a diverse mixture of polycyclic aromatic hydrocarbons (PAHs). Exposure water was seawater free of particulates larger than 0.1 μm. The results of these controlled laboratory studies demonstrated that SPMDs and oysters concentrate the same chemicals but that the relative amounts accumulated are different. For oysters, the 20-d mean (across treatments) concentration factors (CFs) of test compounds with log Kow ≤ 4.8 were much lower (4.0- to 20-fold lower) than those of the same compounds in SPMDs. In contrast, the 20-d CFs of PAHs with log Kow ≥ 5.6 in oysters from the low-level treatment were higher than the corresponding CFs for SPMDs. The CFs of these compounds in oysters from the low-level treatment ranged from approximately 3.0- to 13-fold higher than those in oysters from the high-level treatment. This physiologically mediated difference in oyster CFs appears to be linked to active feeding in the low-level treatment and to apparent toxicity-induced cessation of feeding (i.e., valve closure) in the high-level treatment. Because CFs for these compounds in oysters were not independent of exposure concentrations, it follows that tissue levels were not proportional to exposure concentration. However, both sampling approaches have advantages and disadvantages, and the appropriateness of their use depends on the goals of a given study.

Impact of plant extracts tested in attention-deficit/hyperactivity disorder treatment on cell survival and energy metabolism in human neuroblastoma SH-SY5Y cells.

PubMed

Schmidt, Andreas Johannes; Krieg, Jürgen-Christian; Hemmeter, Ulrich Michael; Kircher, Tilo; Schulz, Eberhard; Clement, Hans-Willi; Heiser, Philip

2010-10-01

Plant extracts such as Hypericum perforatum and Pycnogenol have been tested as alternatives to the classical ADHD drugs. It has been possible to describe neuroprotective effects of such plant extracts. A reduction of ADHD symptoms could be shown in clinical studies after the application of Pycnogenol, which is a pine bark extract. The impacts of the standardized herbal extracts Hypericum perforatum, Pycnogenol and Enzogenol up to a concentration of 5000 ng/mL on cell survival and energy metabolism in human SH-SY5Y neuroblastoma cells has been investigated in the present examination. Hypericum perforatum significantly decreased the survival of cells after treatment with a concentration of 5000 ng/mL, whereas lower concentrations exerted no significant effects. Pycnogenol( induced a significant increase of cell survival after incubation with a concentration of 32.25 ng/mL and a concentration of 250 ng/mL. Other applied concentrations of Pycnogenol failed to exert significant effects. Treatment with Enzogenol did not lead to significant changes in cell survival.Concerning energy metabolism, the treatment of cells with a concentration of 5000 ng/mL Hypericum perforatum led to a significant increase of ATP levels, whereas treatment with a concentration of 500 ng/mL had no significant effect. Incubation of cells with Pycnogenol and Enzogenol exerted no significant effects.None of the tested substances caused any cytotoxic effect when used in therapeutically relevant concentrations. Copyright © 2010 John Wiley & Sons, Ltd.

Repaglinide has more beneficial effect on cardiovascular risk factors than glimepiride: data from meal-test study.

PubMed

Rizzo, M R; Barbieri, M; Grella, R; Passariello, N; Paolisso, G

2005-06-01

Aim our study is to compare the effects of repaglinide vs glimepiride administration on cardiovascular risk factors after meal test. Thus, after 2 weeks washout period, a 3-month randomised, cross-over parallel group trial of repaglinide (1 mg x 2/day) vs glimepiride (2 mg/day) in 14 patients with type 2 diabetes "naive" on diet treatment was made. Both treatments significantly declined plasma glucose, total-cholesterol, LDL-cholesterol, triglycerides, PAI-1, PAP levels and increased HDL-cholesterol. Lowering in plasma PAI-1 and PAP levels was significantly greater in repaglinide group. Furthermore, repaglinide administration resulted in a significant decrease in fasting plasma free fatty acids, fibrinogen, thrombin-antithrombin complex and reaction product of malondialdehyde with thiobarbituric acid (TBARS) levels, in absence of significant difference in fasting plasma insulin levels. Decrease in plasma TBARS levels correlated with the decrease in Plasminogen Activator Inhibitor-1 (r = 0.72; P < 0.003) and free fatty acids concentrations (r = 0.62; P < 0.01). Analysis of the insulin and glucose concentrations throughout the meal test revealed that AUC for glucose (758 +/- 19 vs 780 +/- 28 mg/Lxmin; P = 0.02) was significantly lower after repaglinide than glimepiride administration despite similar AUC for insulin (2327 +/- 269 vs 2148 +/- 292 mU/Lxmin; P = 0.105). At time 120' of meal test, repaglinide vs glimepiride administration was associated with a significant decline in plasma triglycerides, free fatty acids, fibrinogen, Plasminogen Activator Inhibitor-1, plasmin-alpha(2)-antiplasmin complex, thrombin-antithrombin complex, TBARS levels and increase in plasma HDL-cholesterol levels. In repaglinide group a negative correlation between insulin secretion during 1st phase of meal-test and plasma TBARS levels (r = -0.55; P < 0.03) at time 120' was found. Such correlation was lost after adjusting for changes in postprandial hyperglycaemia (r = -0.48; P < 0.09). In conclusion, our results support the hypothesis that repaglinide is more efficient than glimepiride on controlling for postprandial glucose excursion and may have beneficial effect on reducing cardiovascular risk factors.

Ozone removal capability of a welding fume respirator containing activated charcoal.

PubMed

Johnston, A R; Dyrud, J F; Shih, Y T

1989-09-01

Development of air purifying respirators for protection against ozone has been slowed by concerns about oxidation of charcoal and other available sorbents. The suitability of a charcoal sorbent for low concentrations of ozone was evaluated as a part of the development of a half-mask air purifying respirator designed for welding fumes and ozone. Testing of the respirator confirmed that charcoal can be a suitable sorbent for low levels of ozone. Where the respirator is properly selected, fit tested, and worn, respirator use against welding fumes and ozone at concentrations not exceeding 10 times the permissible exposure limit had been recommended.

Rheological properties of the product slurry of the Nitrate to Ammonia and Ceramic (NAC) process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muguercia, I.; Yang, G.; Ebadian, M.A.

The Nitrate to Ammonia and Ceramic (NAC) process is an innovative technology for immobilizing the liquid from Low Level radioactive Waste (LLW). An experimental study was conducted to measure the rheological properties of the pipe flow of the NAC product slurry. Test results indicate that the NAC product slurry has a profound rheological behavior. At low solids concentration, the slurry exhibits a typical dilatant fluid (or shear thinning)fluid. The transition from dilatant fluid to pseudo-plastic fluid will occur at between 25% to 30% solids concentration in temperature ranges of 50--80{degree}C. Correlation equations are developed based on the test data.

In Response: Biological arguments for selecting effect sizes in ecotoxicological testing—A governmental perspective

USGS Publications Warehouse

Mebane, Christopher A.

2015-01-01

Criticisms of the uses of the no-observed-effect concentration (NOEC) and the lowest-observed-effect concentration (LOEC) and more generally the entire null hypothesis statistical testing scheme are hardly new or unique to the field of ecotoxicology [1-4]. Among the criticisms of NOECs and LOECs is that statistically similar LOECs (in terms of p value) can represent drastically different levels of effect. For instance, my colleagues and I found that a battery of chronic toxicity tests with different species and endpoints yielded LOECs with minimum detectable differences ranging from 3% to 48% reductions from controls [5].

Individual and community risk factors and sexually transmitted diseases among arrested youths: a two level analysis.

PubMed

Dembo, Richard; Belenko, Steven; Childs, Kristina; Wareham, Jennifer; Schmeidler, James

2009-08-01

High rates of infection for chlamydia and gonorrhea have been noted among youths involved in the juvenile justice system. Although both individual and community-level factors have been found to be associated with sexually transmitted disease (STD) risk, their relative importance has not been tested in this population. A two-level logistic regression analysis was completed to assess the influence of individual-level and community-level predictors on STD test results among arrested youths processed at a centralized intake facility. Results from weighted two level logistic regression analyses (n = 1,368) indicated individual-level factors of gender (being female), age, race (being African American), and criminal history predicted the youths' positive STD status. For the community-level predictors, concentrated disadvantage significantly and positively predicted the youths' STD status. Implications of these findings for future research and public health policy are discussed.

Mechanisms of tissue uptake and retention of paclitaxel-coated balloons: impact on neointimal proliferation and healing.

PubMed

Granada, Juan F; Stenoien, Mark; Buszman, Piotr P; Tellez, Armando; Langanki, Dan; Kaluza, Greg L; Leon, Martin B; Gray, William; Jaff, Michael R; Schwartz, Robert S

2014-01-01

The efficacy of paclitaxel-coated balloons (PCB) for restenosis prevention has been demonstrated in humans. However, the mechanism of action for sustained drug retention and biological efficacy following single-time drug delivery is still unknown. The pharmacokinetic profile and differences in drug concentration (vessel surface vs arterial wall) of two different paclitaxel coating formulations (3 µg/mm(2)) displaying opposite solubility characteristics (CC=crystalline vs AC=amorphous) were tested in vivo and compared with paclitaxel-eluting stents (PES). Also, the biological effect of both PCB formulations on vascular healing was tested in the porcine coronary injury model. One hour following balloon inflation, both formulations achieved similar arterial paclitaxel levels (CC=310 vs AC=245 ng/mg; p=NS). At 24 h, the CC maintained similar tissue concentrations, whereas the AC tissue levels declined by 99% (p<0.01). At this time point, arterial levels were 20-fold (CC) and 5-fold (AC) times higher compared to the PES group (p<0.05). At 28 days, arterial levels retained were 9.2% (CC) and 0.04% (AC, p<0.01) of the baseline levels. Paclitaxel concentration on the vessel surface was higher in the CC at 1 (CC=36.7% vs AC=13.1%, p<0.05) and 7 days (CC=38.4% vs AC=11%, p<0.05). In addition, the CC induced higher levels of neointimal inhibition, fibrin deposition and delayed healing compared with the AC group. The presence of paclitaxel deposits on the vessel surface driving diffusion into the arterial tissue in a time-dependent fashion supports the mechanism of action of PCB. This specific pharmacokinetic behaviour influences the patterns of neointimal formation and healing.

Mechanisms of tissue uptake and retention of paclitaxel-coated balloons: impact on neointimal proliferation and healing

PubMed Central

Granada, Juan F; Stenoien, Mark; Buszman, Piotr P; Tellez, Armando; Langanki, Dan; Kaluza, Greg L; Leon, Martin B; Gray, William; Jaff, Michael R; Schwartz, Robert S

2014-01-01

Background The efficacy of paclitaxel-coated balloons (PCB) for restenosis prevention has been demonstrated in humans. However, the mechanism of action for sustained drug retention and biological efficacy following single-time drug delivery is still unknown. Methods and results The pharmacokinetic profile and differences in drug concentration (vessel surface vs arterial wall) of two different paclitaxel coating formulations (3 µg/mm2) displaying opposite solubility characteristics (CC=crystalline vs AC=amorphous) were tested in vivo and compared with paclitaxel-eluting stents (PES). Also, the biological effect of both PCB formulations on vascular healing was tested in the porcine coronary injury model. One hour following balloon inflation, both formulations achieved similar arterial paclitaxel levels (CC=310 vs AC=245 ng/mg; p=NS). At 24 h, the CC maintained similar tissue concentrations, whereas the AC tissue levels declined by 99% (p<0.01). At this time point, arterial levels were 20-fold (CC) and 5-fold (AC) times higher compared to the PES group (p<0.05). At 28 days, arterial levels retained were 9.2% (CC) and 0.04% (AC, p<0.01) of the baseline levels. Paclitaxel concentration on the vessel surface was higher in the CC at 1 (CC=36.7% vs AC=13.1%, p<0.05) and 7 days (CC=38.4% vs AC=11%, p<0.05). In addition, the CC induced higher levels of neointimal inhibition, fibrin deposition and delayed healing compared with the AC group. Conclusions The presence of paclitaxel deposits on the vessel surface driving diffusion into the arterial tissue in a time-dependent fashion supports the mechanism of action of PCB. This specific pharmacokinetic behaviour influences the patterns of neointimal formation and healing. PMID:25332821

Comparative toxicities of selected rare earth elements: Sea urchin embryogenesis and fertilization damage with redox and cytogenetic effects.

PubMed

Pagano, Giovanni; Guida, Marco; Siciliano, Antonietta; Oral, Rahime; Koçbaş, Fatma; Palumbo, Anna; Castellano, Immacolata; Migliaccio, Oriana; Thomas, Philippe J; Trifuoggi, Marco

2016-05-01

Broad-ranging adverse effects are known for rare earth elements (REE), yet only a few studies tested the toxicity of several REE, prompting studies focusing on multi-parameter REE toxicity. Trichloride salts of Y, La, Ce, Nd, Sm, Eu and Gd were tested in Paracentrotus lividus sea urchin embryos and sperm for: (1) developmental defects in either REE-exposed larvae or in the offspring of REE-exposed sperm; (2) fertilization success; (3) mitotic anomalies in REE-exposed embryos and in the offspring of REE-exposed sperm, and (4) reactive oxygen species (ROS) formation, and malondialdehyde (MDA) and nitric oxide (NO) levels. REEs affected P. lividus larvae with concentration-related increase in developmental defects, 10(-6) to 10(-4)M, ranking as: Gd(III)>Y(III)>La(III)>Nd(III)≅Eu(III)>Ce(III)≅Sm(III). Nominal concentrations of REE salts were confirmed by inductively coupled plasma mass spectrometry (ICP-MS). Significant increases in MDA levels, ROS formation, and NO levels were found in REE-exposed embryos. Sperm exposure to REEs (10(-5) to 10(-4)M) resulted in concentration-related decrease in fertilization success along with increase in offspring damage. Decreased mitotic activity and increased aberration rates were detected in REE-exposed embryos and in the offspring of REE-exposed sperm. REE-associated toxicity affecting embryogenesis, fertilization, cytogenetic and redox endpoints showed different activities of tested REEs. Damage to early life stages, along with redox and cytogenetic anomalies should be the focus of future REE toxicity studies. Copyright © 2016 Elsevier Inc. All rights reserved.

Description and evaluation of a peracetic acid air sampling and analysis method.

PubMed

Nordling, John; Kinsky, Owen R; Osorio, Magdalena; Pechacek, Nathan

2017-12-01

Peracetic acid (PAA) is a corrosive chemical with a pungent odor, which is extensively used in occupational settings and causes various health hazards in exposed workers. Currently, there is no US government agency recommended method that could be applied universally for the sampling and analysis of PAA. Legacy methods for determining airborne PAA vapor levels frequently suffered from cross-reactivity with other chemicals, particularly hydrogen peroxide (H 2 O 2 ). Therefore, to remove the confounding factor of cross-reactivity, a new viable, sensitive method was developed for assessment of PAA exposure levels, based on the differential reaction kinetics of PAA with methyl p-tolylsulfide (MTS), relative to H 2 O 2 , to preferentially derive methyl p-tolysulfoxide (MTSO). By quantifying MTSO concentration produced in the liquid capture solution from an air sampler, using an internal standard, and utilizing the reaction stoichiometry of PAA and MTS, the original airborne concentration of PAA is determined. After refining this liquid trap high-performance liquid chromatography (HPLC) method in the laboratory, it was tested in five workplace settings where PAA products were used. PAA levels ranged from the detection limit of 0.013 parts per million (ppm) to 0.4 ppm. The results indicate a viable and potentially dependable method to assess the concentrations of PAA vapors under occupational exposure scenarios, though only a small number of field measurements were taken while field testing this method. However, the low limit of detection and precision offered by this method makes it a strong candidate for further testing and validation to expand the uses of this liquid trap HPLC method.

Prevention of CCl4 induced hypogonadism with Raphanus sativus seeds in rat.

PubMed

Tabassum, Farhana; Khan, Muhammad Rashid

2017-03-01

Raphanus sativus seeds are used as condiment and to treat hypogonadism, various ailments of liver and kidneys. The aim of this study was to evaluate the potential protective effects of methanol extract of R. sativus seeds (RSME) against hypogonadism induced with carbon tetrachloride (CCl 4 ) in Sprague-Dawley male rats. Thirty six rats were divided in to six groups with six animals in each. Animals of Group I were control and treated with saline, Group II, III and IV were given orally CCl 4 (1 ml/kg bw; 10% in corn oil). Rats of Group III and IV were also simultaneously given RSME at 100 mg/kg bw and 200 mg/kg bw respectively. However, Group V and VI received RSME (100; 200 mg/kg bw, respectively) alone. All treatments were given at alternate days for 15 days. Treatment of CCl4 to rats decreased (P < 0.001) the level of CAT, POD, SOD, GST, GSH-Px and GSR antioxidant enzymes in testes of rat. Concentration of lipid peroxides (TBARS) was increased (P < 0.001) whereas concentration of GSH was decreased (P < 0.001) in testes of CCl4 treated animals. Concentration of testosterone, FSH and LH in serum was decreased (P < 0.001) while the level of estradiol and prolactin was increased (P < 0.001) in CCl4 treated rats. Injuries in seminiferous tubules were determined in histopathology of testes. Administration of RSME, dose dependently, markedly ameliorated the oxidative stress of CCl4 thereby restoring the level of antioxidant enzymes, lipid peroxides, reduced glutathione, male hormones and alterations in histopathology.

Serum progranulin concentrations are not responsive during oral lipid tolerance test and oral glucose tolerance test.

PubMed

Schmid, A; Leszczak, S; Ober, I; Schäffler, A; Karrasch, T

2015-07-01

The postprandial regulation of progranulin by oral uptake of lipids and carbohydrates in healthy individuals has not yet been investigated. The regulation of progranulin in 2 large cohorts of healthy volunteers during oral lipid tolerance test (OLTT; n=100) and oral glucose tolerance test (OGTT; n=100) was analyzed. One hundred healthy volunteers underwent OLTT and OGTT in an outpatient setting. Venous blood was drawn at 0 hours (h) (fasting) and at 2, 4, and 6 h in OLTT or 1 and 2 h in OGTT. A novel OLTT solution completely free of carbohydrates and protein was applied. Subjects were characterized by anthropometric and laboratory parameters. Serum concentrations of progranulin were measured by enzyme-linked immunosorbent assay (ELISA). Circulating progranulin levels remained unchanged during OLTT and OGTT. Fasting progranulin levels ranged between 31.3±8.7 and 40.6±7.7 ng/ml and were not different in subgroups addressing BMI, gender, family history, smoking habits, and hormonal contraception. There was a reciprocal correlation of progranulin with HDL (negative) and LDL cholesterol levels (positive). In healthy adults, fasting and postprandial circulating progranulin levels are not different in BMI subgroups. Oral uptake of carbohydrates and lipids does not influence circulating progranulin levels in a short-term manner. A postprandial and short-term regulation of this adipokine is absent, at least in healthy subjects. There is a negative correlation of progranulin with HDL cholesterol, but a positive correlation with LDL cholesterol. This reciprocal association might be of physiological importance for an individual's atherosclerotic risk. © Georg Thieme Verlag KG Stuttgart · New York.

From individual to population level effects of toxicants in the tubicifid Branchiura sowerbyi using threshold effect models in a Bayesian framework.

PubMed

Ducrot, Virginie; Billoir, Elise; Péry, Alexandre R R; Garric, Jeanne; Charles, Sandrine

2010-05-01

Effects of zinc were studied in the freshwater worm Branchiura sowerbyi using partial and full life-cycle tests. Only newborn and juveniles were sensitive to zinc, displaying effects on survival, growth, and age at first brood at environmentally relevant concentrations. Threshold effect models were proposed to assess toxic effects on individuals. They were fitted to life-cycle test data using Bayesian inference and adequately described life-history trait data in exposed organisms. The daily asymptotic growth rate of theoretical populations was then simulated with a matrix population model, based upon individual-level outputs. Population-level outputs were in accordance with existing literature for controls. Working in a Bayesian framework allowed incorporating parameter uncertainty in the simulation of the population-level response to zinc exposure, thus increasing the relevance of test results in the context of ecological risk assessment.

Multiscale stochastic simulations for tensile testing of nanotube-based macroscopic cables.

PubMed

Pugno, Nicola M; Bosia, Federico; Carpinteri, Alberto

2008-08-01

Thousands of multiscale stochastic simulations are carried out in order to perform the first in-silico tensile tests of carbon nanotube (CNT)-based macroscopic cables with varying length. The longest treated cable is the space-elevator megacable but more realistic shorter cables are also considered in this bottom-up investigation. Different sizes, shapes, and concentrations of defects are simulated, resulting in cable macrostrengths not larger than approximately 10 GPa, which is much smaller than the theoretical nanotube strength (approximately 100 GPa). No best-fit parameters are present in the multiscale simulations: the input at level 1 is directly estimated from nanotensile tests of CNTs, whereas its output is considered as the input for the level 2, and so on up to level 5, corresponding to the megacable. Thus, five hierarchical levels are used to span lengths from that of a single nanotube (approximately 100 nm) to that of the space-elevator megacable (approximately 100 Mm).

Thermal destruction of wastes containing polychlorinated naphthalenes in an industrial waste incinerator.

PubMed

Yamamoto, Takashi; Noma, Yukio; Sakai, Shin-Ichi

2016-07-02

A series of verification tests were carried out in order to confirm that polychlorinated naphthalenes (PCNs) contained in synthetic rubber products (Neoprene FB products) and aerosol adhesives, which were accidentally imported into Japan, could be thermally destroyed using an industrial waste incinerator. In the verification tests, Neoprene FB products containing PCNs at a concentration of 2800 mg/kg were added to industrial wastes at a ratio of 600 mg Neoprene FB product/kg-waste, and then incinerated at an average temperature of 985 °C. Total PCN concentrations were 14 ng/m 3 N in stack gas, 5.7 ng/g in bottom ash, 0.98 ng/g in boiler dust, and 1.2 ng/g in fly ash. Destruction efficiency (DE) and destruction removal efficiency (DRE) of congener No. 38/40, which is considered an input marker congener, were 99.9974 and 99.9995 %, respectively. The following dioxin concentrations were found: 0.11 ng-TEQ/m 3 N for the stack gas, 0.096 ng-TEQ/g for the bottom ash, 0.010 ng-TEQ/g for the boiler dust, and 0.072 ng-TEQ/g for the fly ash. Since the PCN levels in the PCN destruction test were even at slightly lower concentrations than in the baseline test without PCN addition, the detected PCNs are to a large degree unintentionally produced PCNs and does not mainly stem from input material. Also, the dioxin levels did not change. From these results, we confirmed that PCNs contained in Neoprene FB products and aerosol adhesives could be destroyed to a high degree by high-temperature incineration. Therefore, all recalled Neoprene FB products and aerosol adhesives containing PCNs were successfully treated under the same conditions as the verification tests.

The chemical exposure toxicity space (CETS) model: Displaying exposure time, aqueous and organic concentration, activity, and onset of toxicity.

PubMed

Mackay, Donald; Celsie, Alena K D; Parnis, J Mark; McCarty, Lynn S; Arnot, Jon A; Powell, David E

2017-05-01

A 1-compartment toxicokinetic model is used to characterize the chemical exposure toxicity space (CETS), providing a novel graphic tool that can aid in the design of aquatic toxicity tests for fish and for interpreting their results. The graph depicts the solution to the differential equation describing the uptake kinetics of a chemical by a modeled fish under conventional bioassay conditions. The model relates the exposure concentration in the water to a dimensionless time and the onset of toxicity as determined by an estimated or assumed critical body residue or incipient lethal aqueous concentration. These concentration graphs are specific to each chemical and exposure and organism parameters and clearly demonstrate differences in toxicity between chemicals and how factors such as hydrophobicity influence the toxic endpoint. The CETS plots can also be used to assess bioconcentration test conditions to ensure that concentrations are well below toxic levels. Illustrative applications are presented using a recent set of high-quality toxicity data. Conversion of concentrations to chemical activities in the plots enables results for different baseline toxicants to be superimposed. For chemicals that have different modes of toxic action, the increased toxicity then becomes apparent. Implications for design and interpretation of aquatic toxicity tests are discussed. The model, and pictorial visualization of the time-course of aquatic toxicity tests, may contribute to improvements in test design, implementation, and interpretation, and to reduced animal usage. Environ Toxicol Chem 2017;36:1389-1396. © 2016 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC. © 2016 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC.

Alpha-tocopherol and alpha-tocopheryl quinone levels in cervical intraepithelial neoplasia and cervical cancer.

PubMed

Palan, Prabhudas R; Woodall, Angela L; Anderson, Patrick S; Mikhail, Magdy S

2004-05-01

alpha-Tocopherol is a potent antioxidant that protects cell membranes against oxidative damage. Red blood cell alpha-tocopherol levels reflect membrane alpha-tocopherol concentrations, and altered levels may suggest membrane damage. The objective of this study was to determine the levels of alpha-tocopherol and alpha-tocopheryl quinone, the oxidized product of alpha-tocopherol, in plasma and red blood cells that were obtained from control subjects and patients with cervical intraepithelial neoplasia and cervical cancer. In this cross-sectional study, 72 women, (32 African American and 40 Hispanic) were recruited. Among these subjects, 37 women had cervical intraepithelial neoplasia; 14 women had cervical cancer, and 21 women were considered control subjects, who had normal Papanicolaou test results. alpha-Tocopherol and alpha-tocopheryl quinone levels were determined in red blood cell and plasma by high-pressure liquid chromatography. Plasma levels of alpha-tocopherol and alpha-tocopheryl quinone were decreased significantly (P=.012 and=.005, respectively, by Kruskal-Wallis test) in study groups compared with the control group; red blood cell levels of alpha-tocopherol and alpha-tocopheryl quinone were not altered significantly. The lower alpha-tocopherol level that was observed in this study is consistent with our previous reports of decreased antioxidant concentrations and increased oxidative stress in women with cervical intraepithelial neoplasia. Unaltered red blood cell alpha-tocopherol and alpha-tocopheryl quinone levels suggest undamaged cell membrane. Further studies are needed to investigate the potential role of oxidative stress in cervical intraepithelial neoplasia.

Data Processing at the High School Level.

ERIC Educational Resources Information Center

Richmond, Sue

1981-01-01

The teaching of data processing in the secondary school is examined, including teachers (certification, work experience), textbooks (selection, concentration), community (advisory committees, career exploration), students (recruitment, aptitude tests), instruction methods (simulation, audiovisuals, field trips), course content (machine technology,…

Checking Trace Nitrate in Water and Soil Using an Amateur Scientist's Measurement Guide.

ERIC Educational Resources Information Center

Baker, Roger C. Jr.

1995-01-01

Presents a test that can measure nitrate nitrogen ions at about 0.1 mg/L using concentration. Uses inexpensive accessible materials and can be used by amateur environmentalists for monitoring water nitrate levels. (JRH)

Hsp70 as an indicator of stress in the cells after contact with nanoparticles

NASA Astrophysics Data System (ADS)

Hardilová, Šárka; Havrdová, Markéta; Panáček, Aleš; Kvítek, Libor; Zbořil, Radek

2015-05-01

In recent years, production of nanoparticles is increased and thus grows our contact with them too. Question of safety is closely related to the issue of use nanoparticles. There are a number of tests that monitor the viability, ROS production, the effect on the DNA and cell cycle, however, rarely encountered studies on stress in the cells after contact with nanoparticles. Heat shock proteins (HSP) are among the substances that can be used for monitoring stress in cells. HSP are structures with a chaperone activity. They are evolutionarily very old, conservative and they are found with a high degree of homology in prokaryotes and eukaryotes including humans. They exist at low concentrations under physiological conditions, while in the denaturing conditions e.g. high or low temperature, radiation, exposure to chemicals, heavy metals, or nanoparticles their expression is changed. HSPs are involved in maintaining homeostasis in the cell that the denatured protein conformations allow recovery to the original stage. One of the most common proteins from HSP family is Hsp70 - protein with a molecular weight of 70 kDa. The level of Hsp70 in a cell after exposure to the stress changes depending on the stress level to which the cell is exposed to and a time period during which lasted stressful conditions. Our research monitors stress levels of cells manifesting by Hsp70 production after contact with silver nanoparticles. Nanoparticles show different toxicity towards different types of target cells, which is reflected in the values of IC50 - concentration that kills 50% tested cells. Concentration of test substance toxic to one cell type may be innocuous to cells of another type. IC50 obtained from the MTT assay provides a suitable default data and if multiples of IC50 values are used, we can compare and generalize. Studies can be used to compare stress levels in cells that show different sensitivity to the tested nanoparticles compared with cells under optimal growth conditions. The study was done on two types of mouse fibroblasts NIH-3T3 and L929. While NIH-3T3 cells exhibit stress response proportional to the concentration of silver nanoparticles, for L929 cells this was not observed.

On-line measurement of heat of combustion

NASA Technical Reports Server (NTRS)

Chaturvedi, S. K.; Chegini, H.

1988-01-01

An experimental method for an on-line measurement of heat of combustion of a gaseous hydrocarbon fuel mixture of unknown composition is developed. It involves combustion of a test gas with a known quantity of air to achieve a predetermined oxygen concentration level in the combustion products. This is accomplished by a feedback controller which maintains the gas volumetric flow rate at a level consistent with the desired oxygen concentration in the products. The heat of combustion is determined from a known correlation with the gas volumetric flow rate. An on-line microcomputer accesses the gas volumetric flow data, and displays the heat of combustion values at desired time intervals.

Comparative toxicant sensitivity of sexual and asexual reproduction in the rotifer Brachionus calyciflorus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Snell, T.W.; Carmona, M.J.

Cyclically parthenogenetic zooplankters like rotifers are important tools for assessing toxicity in aquatic environments. Sexual reproduction is an essential component of rotifer life cycles, but current toxicity tests utilize only asexual reproduction. The authors compared the effects of four toxicants on asexual and sexual reproduction of the rotifer Brachionus calyciflorus. Toxicants had a differential effect on sexual and asexual reproduction, with sexual reproduction consistently the most sensitive. Concentrations of 0.2 {mu}g/ml PCP (sodium pentachlorophenate) had no effect on the asexual reproductive rate, but significantly reduced sexual reproduction. Likewise, chlorpyrifos concentrations of 0.3 {mu}g/ml had no significant effect on asexual reproduction,more » but sexual reproduction was significantly reduced. There was no difference in NOECs, LOECs, and chronic values for asexual and sexual reproduction for cadmium and naphthol tests. However, comparison of toxicant effect levels revealed that sexual reproduction was more strongly reduced at each toxicant concentration. The four toxicants tested inhibited sexual reproduction 2 to 68 times more than asexual reproduction at the lowest observed effect concentrations. Toxicants inhibited sexual reproduction in its initial step: sexual female production. Because sexual reproduction is more sensitive, toxicity tests based exclusively on asexual reproduction may not be protective of rotifer life cycles.« less

Use of implantable pellets to administer low levels of methyl mercury to fish

USGS Publications Warehouse

Arnold, B.S.; Jagoe, C.H.; Gross, T.S.

1999-01-01

Implantable pellets of methyl mercury chloride were tested in Nile Tilapia (Oreochromis niloticus) to appraise the effectiveness of the method for chronic studies of mercury. Two dosing regimes of 15 and 1.5 grams/CH3HgCl pellet (test 1) and 1 and 0.1 grams/pellet (test 2-3) of methyl mercury chloride were used in three tests. Additional pellets containing only matrix were used as controls. The pellets were inserted into the peritoneal cavity along with a microchip for identification. Three methods of incision closure: sutures and two types of surgical glue, were tested. Pellets used in test one released the dose too fast, resulting in premature death of the fish. Results from test 2 and 3 show blood mercury concentrations over time and tissue levels at necropsy consistent with dose suggesting that this is a viable method of dosing fish.

End Criteria for Reaching Maximal Oxygen Uptake Must Be Strict and Adjusted to Sex and Age: A Cross-Sectional Study

PubMed Central

Edvardsen, Elisabeth; Hem, Erlend; Anderssen, Sigmund A.

2014-01-01

Objective To describe different end criteria for reaching maximal oxygen uptake (VO2max) during a continuous graded exercise test on the treadmill, and to explore the manner by which different end criteria have an impact on the magnitude of the VO2max result. Methods A sample of 861 individuals (390 women) aged 20–85 years performed an exercise test on a treadmill until exhaustion. Gas exchange, heart rate, blood lactate concentration and Borg Scale6–20 rating were measured, and the impact of different end criteria on VO2max was studied;VO2 leveling off, maximal heart rate (HRmax), different levels of respiratory exchange ratio (RER), and postexercise blood lactate concentration. Results Eight hundred and four healthy participants (93%) fulfilled the exercise test until voluntary exhaustion. There were no sex-related differences in HRmax, RER, or Borg Scale rating, whereas blood lactate concentration was 18% lower in women (P<0.001). Forty-two percent of the participants achieved a plateau in VO2; these individuals had 5% higher ventilation (P = 0.033), 4% higher RER (P<0.001), and 5% higher blood lactate concentration (P = 0.047) compared with participants who did not reach a VO2 plateau. When using RER ≥1.15 or blood lactate concentration ≥8.0 mmol•L–1, VO2max was 4% (P = 0.012) and 10% greater (P<0.001), respectively. A blood lactate concentration ≥8.0 mmol•L–1 excluded 63% of the participants in the 50–85-year-old cohort. Conclusions A range of typical end criteria are presented in a random sample of subjects aged 20–85 years. The choice of end criteria will have an impact on the number of the participants as well as the VO2max outcome. Suggestions for new recommendations are given. PMID:24454832

Repellent effect of santalol from sandalwood oil against Tetranychus urticae (Acari: Tetranychidae).

PubMed

Roh, Hyun Sik; Park, Kye Chung; Park, Chung Gyoo

2012-04-01

Thirty-four essential oils were screened for their repellent activities against the twospotted spider mite, Tetranychus urticae Koch (Acarina: Tetranychidae), at 0.1% concentration level using choice and no-choice laboratory bioassays. Of these, 20 essential oils showed significant repellencies against T. urticae in the choice tests. In subsequent no-choice tests using these 20 essential oils, only sandalwood oil showed significant repellency against T. urticae. Total number of eggs oviposited by T. urticae was significantly lower than controls in the choice tests when the kidney bean leaves were treated with 1 of 14 essential oils. The significant repellency of sandalwood oil against T. urticae lasted at least for 5 h at the 0.1% concentration level. Our GC-MS analysis indicated that the major components of the sandalwood oil were alpha-santalol (45.8%), beta-santalol (20.6%), beta-sinensal (9.4%), and epi-beta-santalol (3.3%). Santanol, a mixture of the two main components in the sandalwood oil, appears to be responsible for the repellency of sandalwood oil against T. urticae.

Spatial and temporal variability of fluoride concentrations in groundwater resources of Larestan and Gerash regions in Iran from 2003 to 2010.

PubMed

Amini, Hassan; Haghighat, Gholam Ali; Yunesian, Masud; Nabizadeh, Ramin; Mahvi, Amir Hossein; Dehghani, Mohammad Hadi; Davani, Rahim; Aminian, Abd-Rasool; Shamsipour, Mansour; Hassanzadeh, Naser; Faramarzi, Hossein; Mesdaghinia, Alireza

2016-02-01

There is discrepancy about intervals of fluoride monitoring in groundwater resources by Iranian authorities. Spatial and temporal variability of fluoride in groundwater resources of Larestan and Gerash regions in Iran were analyzed from 2003 to 2010 using a geospatial information system and the Mann-Kendall trend test. The mean concentrations of fluoride for the 8-year period in the eight cities and 31 villages were 1.6 and 2.0 mg/l, respectively; the maximum values were 2.4 and 3.8 mg/l, respectively. Spatial, temporal, and spatiotemporal variability of fluoride in overall groundwater resources were relatively constant over the years. However, results of the Mann-Kendall trend test revealed a monotonic trend in the time series of one city and 11 villages for the 8-year period. Specifically, one city and three villages showed positive significant Kendall's Tau values, suggesting an upward trend in fluoride concentrations over the 8-year period. In contrast, seven villages displayed negative significant Kendall's Tau values, arguing for a downward trend in fluoride concentrations over the years. From 2003 to 2010, approximately 52 % of the Larestan and Gerash areas have had fluoride concentrations above the maximum permissible Iranian drinking water standard fluoride level (1.4 mg/l), and about 116,000 people were exposed to such excess amounts. Therefore, our study supports for a close monitoring of fluoride concentrations from health authorities in monthly intervals, especially in villages and cities that showed positive trend in fluoride concentrations. Moreover, we recommend simultaneous implementation of cost-effective protective measures or interventions until a standard fluoride level is achieved.

Impact of ocean acidification on Arctic phytoplankton blooms and dimethyl sulfide concentration under simulated ice-free and under-ice conditions

NASA Astrophysics Data System (ADS)

Hussherr, Rachel; Levasseur, Maurice; Lizotte, Martine; Tremblay, Jean-Éric; Mol, Jacoba; Thomas, Helmuth; Gosselin, Michel; Starr, Michel; Miller, Lisa A.; Jarniková, Tereza; Schuback, Nina; Mucci, Alfonso

2017-05-01

In an experimental assessment of the potential impact of Arctic Ocean acidification on seasonal phytoplankton blooms and associated dimethyl sulfide (DMS) dynamics, we incubated water from Baffin Bay under conditions representing an acidified Arctic Ocean. Using two light regimes simulating under-ice or subsurface chlorophyll maxima (low light; low PAR and no UVB) and ice-free (high light; high PAR + UVA + UVB) conditions, water collected at 38 m was exposed over 9 days to 6 levels of decreasing pH from 8.1 to 7.2. A phytoplankton bloom dominated by the centric diatoms Chaetoceros spp. reaching up to 7.5 µg chlorophyll a L-1 took place in all experimental bags. Total dimethylsulfoniopropionate (DMSPT) and DMS concentrations reached 155 and 19 nmol L-1, respectively. The sharp increase in DMSPT and DMS concentrations coincided with the exhaustion of NO3- in most microcosms, suggesting that nutrient stress stimulated DMS(P) synthesis by the diatom community. Under both light regimes, chlorophyll a and DMS concentrations decreased linearly with increasing proton concentration at all pH levels tested. Concentrations of DMSPT also decreased but only under high light and over a smaller pH range (from 8.1 to 7.6). In contrast to nano-phytoplankton (2-20 µm), pico-phytoplankton ( ≤ 2 µm) was stimulated by the decreasing pH. We furthermore observed no significant difference between the two light regimes tested in term of chlorophyll a, phytoplankton abundance and taxonomy, and DMSP and DMS net concentrations. These results show that ocean acidification could significantly decrease the algal biomass and inhibit DMS production during the seasonal phytoplankton bloom in the Arctic, with possible consequences for the regional climate.

The toxicological properties of petroleum gases.

PubMed

McKee, Richard H; Herron, Deborah; Saperstein, Mark; Podhasky, Paula; Hoffman, Gary M; Roberts, Linda

2014-01-01

To characterize the toxicological hazards of petroleum gases, 90-day inhalation toxicity (Organization for Economic Cooperation and Development [OECD] 413) and developmental toxicity (OECD 414) tests were conducted with liquefied propane gas (LPG) at concentrations of 1000, 5000, or 10,000 ppm. A micronucleus test (OECD 474) of LPG was also conducted. No systemic or developmental effects were observed; the overall no observed adverse effect concentration (NOAEC) was 10,000 ppm. Further, there was no effect of LPG exposure at levels up to 10,000 ppm on micronucleus induction and no evidence of bone marrow toxicity. Other alkane gases (ethane, propane, n-butane, and isobutane) were then evaluated in combined repeated exposure studies with reproduction/development toxicity screening tests (OECD 422). There were no toxicologically important changes in parameters relating to systemic toxicity or neurotoxicity for any of these gases at concentrations ranging from 9000 to 16,000 ppm. There was no evidence of effects on developmental or reproductive toxicity in the studies of ethane, propane, or n-butane at the highest concentrations tested. However, there was a reduction in mating in the high-exposure group (9000 ppm) of the isobutane study, which although not significantly different was outside the range previously observed in the testing laboratory. Assuming the reduction in mating to have been toxicologically significant, the NOAEC for the isobutane reproductive toxicity screening test was 3000 ppm (7125 mg/m(3)). A method is proposed by which the toxicity of any of the 106 complex petroleum gas streams can be estimated from its composition.

Blood Lead Level Among Fuel Station Workers

PubMed Central

Al-Rudainy, Laith Abdulmajeed

2010-01-01

Objectives This study aims to determine the level of lead in blood of fuel station workers and in a group of people not occupationally exposed to lead Methods 53 control subjects with low risk lead exposure and 45 fuel station workers comprising the study group were included in this study in a period from September 2008 to December 2009. Blood samples were collected and analyzed for each subject by Lead Care Blood Testing System. The average blood lead levels of each group were compared using the independent sample (Mann – Whitney U) test. Results The median (range) 14.1 (7.5–56) μg/dl concentration of lead in the blood of fuel stations workers was significantly higher than the median (range) 6.5 (4.0–1.6) μg/dl concentration of lead in the blood of the control group (p< 0.001).The results obtained also showed that the values of blood lead levels in many workers were higher than action and upper limits acceptable for adults. In fuel station workers, the duration of exposure to leaded fuel was significantly correlated with the blood lead level. Conclusions Occupational exposure to lead is prevalent among many fuel station workers in Basrah. A policy action to improve working conditions and to phase out the use of leaded gasoline is recommended. PMID:22043339

PAH toxicity at aqueous solubility in the fish embryo test with Danio rerio using passive dosing.

PubMed

Seiler, Thomas-Benjamin; Best, Nina; Fernqvist, Margit Møller; Hercht, Hendrik; Smith, Kilian E C; Braunbeck, Thomas; Mayer, Philipp; Hollert, Henner

2014-10-01

As part of the risk assessment process within REACh, prior to manufacturing and distribution of chemical substances their (eco)toxicological impacts have to be investigated. The fish embryo toxicity test (FET) with the zebrafish Danio rerio has gained a high significance as an in vitro alternative to animal testing in (eco)toxicology. However, for hydrophobic organic chemicals it remains a technical challenge to ensure constant freely dissolved concentration at the maximum exposure level during such biotests. Passive dosing with PDMS silicone was thus applied to control the freely dissolved concentration of ten PAHs at their saturation level in the FET. The experiments gave repeatable results, with the toxicity of the PAHs generally increasing with the maximum chemical activities of the PAHs. HPLC analysis confirmed constant exposure at the saturation level. In additional experiments, fish embryos without direct contact to the silicone surface showed similar mortalities as those exposed with direct contact to the silicone. Silicone oil overlaying the water phase as a novel passive dosing phase had no observable effects on the development of the fish embryos until hatching. This study provides further data to support the close relationship between the chemical activity and the toxicity of hydrophobic organic compounds. Passive dosing from PDMS silicone enabled reliable toxicity testing of (highly) hydrophobic substances at aqueous solubility, providing a practical way to control toxicity exactly at the maximum exposure level. This approach is therefore expected to be useful as a cost-effective initial screening of hydrophobic chemicals for potential adverse effects to freshwater vertebrates. Copyright © 2014 Elsevier Ltd. All rights reserved.

Detection of deep-level defects and reduced carrier concentration in Mg-ion-implanted GaN before high-temperature annealing

NASA Astrophysics Data System (ADS)

Akazawa, Masamichi; Yokota, Naoshige; Uetake, Kei

2018-02-01

We report experimental results for the detection of deep-level defects in GaN after Mg ion implantation before high-temperature annealing. The n-type GaN samples were grown on GaN free-standing substrates by metalorganic vapor phase epitaxy. Mg ions were implanted at 50 keV with a small dosage of 1.5×1011 cm-2, which did not change the conduction type of the n-GaN. By depositing Al2O3 and a Ni/Au electrode onto the implanted n-GaN, metal-oxide-semiconductor (MOS) diodes were fabricated and tested. The measured capacitance-voltage (C-V) characteristics showed a particular behavior with a plateau region and a region with an anomalously steep slope. Fitting to the experimental C-V curves by simulation showed the existence of deep-level defects and a reduction of the carrier concentration near the GaN surface. By annealing at 800oC, the density of the deep-level defects was reduced and the carrier concentration partially recovered.

Individual Income, Area Deprivation, and Health: Do Income-Related Health Inequalities Vary by Small Area Deprivation?

PubMed

Siegel, Martin; Mielck, Andreas; Maier, Werner

2015-11-01

This paper aims to explore potential associations between health inequalities related to socioeconomic deprivation at the individual and the small area level. We use German cross-sectional survey data for the years 2002 and 2006, and measure small area deprivation via the German Index of Multiple Deprivation. We test the differences between concentration indices of income-related and small area deprivation related inequalities in obesity, hypertension, and diabetes. Our results suggest that small area deprivation and individual income both yield inequalities in health favoring the better-off, where individual income-related inequalities are significantly more pronounced than those related to small area deprivation. We then apply a semiparametric extension of Wagstaff's corrected concentration index to explore how individual-level health inequalities vary with the degree of regional deprivation. We find that the concentration of obesity, hypertension, and diabetes among lower income groups also exists at the small area level. The degree of deprivation-specific income-related inequalities in the three health outcomes exhibits only little variations across different levels of multiple deprivation for both sexes. Copyright © 2014 John Wiley & Sons, Ltd.

Experimental measurements of the ground cloud effluents and cloud growth for the May 20, 1975, Titan 3C launch at Air Force Eastern Test Range, Florida

NASA Technical Reports Server (NTRS)

Gregory, G. L.; Storey, R. W., Jr.

1977-01-01

The experiment included surface level and airborne in situ cloud measurements of the exhaust effluents from the Titan IIIC solid rocket boosters. Simultaneous visible spectrum photographic pictures of the ground cloud as well as infrared imaging of the cloud were obtained to study the cloud rise, growth, and direction of travel within the earth's surface mixing layer. The NASA multilayer diffusion model predictions of cloud growth, direction of travel, and expected surface level effluent concentrations were made prior to launch and after launch using measured meteorological conditions. Prelaunch predictions were used to position the effluent monitoring instruments, and the postlaunch predictions were compared with the measured data. Measurement results showed that surface level effluent values were low, often below the detection limits of the instrumentation. The maximum surface level hydrogen chloride concentration measured 50 parts per billion at about 8 km from the launch pad. The maximum observed in-cloud (airborne measurement) hydrogen chloride concentration was 7 per million.

Promoting smoke-free homes: a novel behavioral intervention using real-time audio-visual feedback on airborne particle levels.

PubMed

Klepeis, Neil E; Hughes, Suzanne C; Edwards, Rufus D; Allen, Tracy; Johnson, Michael; Chowdhury, Zohir; Smith, Kirk R; Boman-Davis, Marie; Bellettiere, John; Hovell, Melbourne F

2013-01-01

Interventions are needed to protect the health of children who live with smokers. We pilot-tested a real-time intervention for promoting behavior change in homes that reduces second hand tobacco smoke (SHS) levels. The intervention uses a monitor and feedback system to provide immediate auditory and visual signals triggered at defined thresholds of fine particle concentration. Dynamic graphs of real-time particle levels are also shown on a computer screen. We experimentally evaluated the system, field-tested it in homes with smokers, and conducted focus groups to obtain general opinions. Laboratory tests of the monitor demonstrated SHS sensitivity, stability, precision equivalent to at least 1 µg/m(3), and low noise. A linear relationship (R(2) = 0.98) was observed between the monitor and average SHS mass concentrations up to 150 µg/m(3). Focus groups and interviews with intervention participants showed in-home use to be acceptable and feasible. The intervention was evaluated in 3 homes with combined baseline and intervention periods lasting 9 to 15 full days. Two families modified their behavior by opening windows or doors, smoking outdoors, or smoking less. We observed evidence of lower SHS levels in these homes. The remaining household voiced reluctance to changing their smoking activity and did not exhibit lower SHS levels in main smoking areas or clear behavior change; however, family members expressed receptivity to smoking outdoors. This study established the feasibility of the real-time intervention, laying the groundwork for controlled trials with larger sample sizes. Visual and auditory cues may prompt family members to take immediate action to reduce SHS levels. Dynamic graphs of SHS levels may help families make decisions about specific mitigation approaches.

Promoting Smoke-Free Homes: A Novel Behavioral Intervention Using Real-Time Audio-Visual Feedback on Airborne Particle Levels

PubMed Central

Klepeis, Neil E.; Hughes, Suzanne C.; Edwards, Rufus D.; Allen, Tracy; Johnson, Michael; Chowdhury, Zohir; Smith, Kirk R.; Boman-Davis, Marie; Bellettiere, John; Hovell, Melbourne F.

2013-01-01

Interventions are needed to protect the health of children who live with smokers. We pilot-tested a real-time intervention for promoting behavior change in homes that reduces second hand tobacco smoke (SHS) levels. The intervention uses a monitor and feedback system to provide immediate auditory and visual signals triggered at defined thresholds of fine particle concentration. Dynamic graphs of real-time particle levels are also shown on a computer screen. We experimentally evaluated the system, field-tested it in homes with smokers, and conducted focus groups to obtain general opinions. Laboratory tests of the monitor demonstrated SHS sensitivity, stability, precision equivalent to at least 1 µg/m3, and low noise. A linear relationship (R2 = 0.98) was observed between the monitor and average SHS mass concentrations up to 150 µg/m3. Focus groups and interviews with intervention participants showed in-home use to be acceptable and feasible. The intervention was evaluated in 3 homes with combined baseline and intervention periods lasting 9 to 15 full days. Two families modified their behavior by opening windows or doors, smoking outdoors, or smoking less. We observed evidence of lower SHS levels in these homes. The remaining household voiced reluctance to changing their smoking activity and did not exhibit lower SHS levels in main smoking areas or clear behavior change; however, family members expressed receptivity to smoking outdoors. This study established the feasibility of the real-time intervention, laying the groundwork for controlled trials with larger sample sizes. Visual and auditory cues may prompt family members to take immediate action to reduce SHS levels. Dynamic graphs of SHS levels may help families make decisions about specific mitigation approaches. PMID:24009742

Acquisition Practices Used at United States Marine Corps Program Executive Officer Land Systems: Program Manager Medium and Heavy Tactical Vehicles

DTIC Science & Technology

2014-09-22

2010, the Naval Air Warfare Center–Weapons Division, China Lake , California, tested commercial fire suppression systems for use in U.S. Marine Corps...review, the excessive concentrations of carbon monoxide, nitrous oxide, hydrogen cyanide , and the acid gases experienced during the Molotov...excessive concentration levels of carbon monoxide, nitrous oxide, hydrogen cyanide , and the acid gases were identified during the Molotov cocktail live

A hybrid interface tracking - level set technique for multiphase flow with soluble surfactant

NASA Astrophysics Data System (ADS)

Shin, Seungwon; Chergui, Jalel; Juric, Damir; Kahouadji, Lyes; Matar, Omar K.; Craster, Richard V.

2018-04-01

A formulation for soluble surfactant transport in multiphase flows recently presented by Muradoglu and Tryggvason (JCP 274 (2014) 737-757) [17] is adapted to the context of the Level Contour Reconstruction Method, LCRM, (Shin et al. IJNMF 60 (2009) 753-778, [8]) which is a hybrid method that combines the advantages of the Front-tracking and Level Set methods. Particularly close attention is paid to the formulation and numerical implementation of the surface gradients of surfactant concentration and surface tension. Various benchmark tests are performed to demonstrate the accuracy of different elements of the algorithm. To verify surfactant mass conservation, values for surfactant diffusion along the interface are compared with the exact solution for the problem of uniform expansion of a sphere. The numerical implementation of the discontinuous boundary condition for the source term in the bulk concentration is compared with the approximate solution. Surface tension forces are tested for Marangoni drop translation. Our numerical results for drop deformation in simple shear are compared with experiments and results from previous simulations. All benchmarking tests compare well with existing data thus providing confidence that the adapted LCRM formulation for surfactant advection and diffusion is accurate and effective in three-dimensional multiphase flows with a structured mesh. We also demonstrate that this approach applies easily to massively parallel simulations.

Dietary risk evaluation for 28 polycyclic aromatic hydrocarbons (PAHs) in tea preparations made of teas available on the Polish retail market.

PubMed

Roszko, Marek; Kamińska, Marta; Szymczyk, Krystyna; Jędrzejczak, Renata

2018-01-02

The aim of this work was to assess dietary risk resulting from consumption of polycyclic aromatic hydrocarbons (PAHs) with tea infusions. To this end, levels of 28 PAHs in black, green, red and white teas available on the Polish retail market have been assessed. Profiles and correlation between concentrations of individual PAHs have been identified. A model study on transfer of PAHs from tea leaves into tea preparations has been conducted. Relatively high concentrations of 28 evaluated PAHs have been found in 58 tested samples of black, green, red and white teas sampled on the Polish retail market. Total concentration ∑28PAH ranged from 57 to 696 µg kg -1 with mean 258 µg kg -1 (dry tea leaves). The most mature tea leaves fermented to a small degree contained relatively the highest PAH levels among all four tested tea types. Relatively low PAH transfer rates into tea infusions and limited volumes of the consumed tea keep the risks associated with PAH dietary intake at a safely low level. The worst-case scenario dietary intake values were 7.62/0.82/0.097 ng kg -1 b.w. day -1 (estimated on the basis of the maximum found concentrations 696/113/23 µg kg -1 and maximum observed transfer rates 24/16/9%) for ∑28PAH/∑PAH4/B[a]P, respectively. MOE values calculated using the above worst case estimates exceeded 700,000 and 400,000 (BMDL 10 0.07 and 0.34 mg kg -1 b.w. day -1 ) for B[a]P and PAH4, respectively. Both B[a]P and PAH4 concentrations may be used as indicators of total PAH concentration in tea leaves; PAH4 slightly better fits low molecular weight PAHs. Several correlations between various PAHs/groups of PAHs have been identified, the strongest one (R 2 = 0.92) between PAH4 and EU PAH 15+1.

Short-term effect of nutrient availability and rainfall distribution on biomass production and leaf nutrient content of savanna tree species.

PubMed

Barbosa, Eduardo R M; Tomlinson, Kyle W; Carvalheiro, Luísa G; Kirkman, Kevin; de Bie, Steven; Prins, Herbert H T; van Langevelde, Frank

2014-01-01

Changes in land use may lead to increased soil nutrient levels in many ecosystems (e.g. due to intensification of agricultural fertilizer use). Plant species differ widely in their response to differences in soil nutrients, and for savannas it is uncertain how this nutrient enrichment will affect plant community dynamics. We set up a large controlled short-term experiment in a semi-arid savanna to test how water supply (even water supply vs. natural rainfall) and nutrient availability (no fertilisation vs. fertilisation) affects seedlings' above-ground biomass production and leaf-nutrient concentrations (N, P and K) of broad-leafed and fine-leafed tree species. Contrary to expectations, neither changes in water supply nor changes in soil nutrient level affected biomass production of the studied species. By contrast, leaf-nutrient concentration did change significantly. Under regular water supply, soil nutrient addition increased the leaf phosphorus concentration of both fine-leafed and broad-leafed species. However, under uneven water supply, leaf nitrogen and phosphorus concentration declined with soil nutrient supply, this effect being more accentuated in broad-leafed species. Leaf potassium concentration of broad-leafed species was lower when growing under constant water supply, especially when no NPK fertilizer was applied. We found that changes in environmental factors can affect leaf quality, indicating a potential interactive effect between land-use changes and environmental changes on savanna vegetation: under more uneven rainfall patterns within the growing season, leaf quality of tree seedlings for a number of species can change as a response to changes in nutrient levels, even if overall plant biomass does not change. Such changes might affect herbivore pressure on trees and thus savanna plant community dynamics. Although longer term experiments would be essential to test such potential effects of eutrophication via changes in leaf nutrient concentration, our findings provide important insights that can help guide management plans that aim to preserve savanna biodiversity.

Effect of drilling fluid systems and temperature on oil mist and vapour levels generated from shale shaker.

PubMed

Steinsvåg, Kjersti; Galea, Karen S; Krüger, Kirsti; Peikli, Vegard; Sánchez-Jiménez, Araceli; Sætvedt, Esther; Searl, Alison; Cherrie, John W; van Tongeren, Martie

2011-05-01

Workers in the drilling section of the offshore petroleum industry are exposed to air pollutants generated by drilling fluids. Oil mist and oil vapour concentrations have been measured in the drilling fluid processing areas for decades; however, little work has been carried out to investigate exposure determinants such as drilling fluid viscosity and temperature. A study was undertaken to investigate the effect of two different oil-based drilling fluid systems and their temperature on oil mist, oil vapour, and total volatile organic compounds (TVOC) levels in a simulated shale shaker room at a purpose-built test centre. Oil mist and oil vapour concentrations were sampled simultaneously using a sampling arrangement consisting of a Millipore closed cassette loaded with glass fibre and cellulose acetate filters attached to a backup charcoal tube. TVOCs were measured by a PhoCheck photo-ionization detector direct reading instrument. Concentrations of oil mist, oil vapour, and TVOC in the atmosphere surrounding the shale shaker were assessed during three separate test periods. Two oil-based drilling fluids, denoted 'System 2.0' and 'System 3.5', containing base oils with a viscosity of 2.0 and 3.3-3.7 mm(2) s(-1) at 40°C, respectively, were used at temperatures ranging from 40 to 75°C. In general, the System 2.0 yielded low oil mist levels, but high oil vapour concentrations, while the opposite was found for the System 3.5. Statistical significant differences between the drilling fluid systems were found for oil mist (P = 0.025),vapour (P < 0.001), and TVOC (P = 0.011). Increasing temperature increased the oil mist, oil vapour, and TVOC levels. Oil vapour levels at the test facility exceeded the Norwegian oil vapour occupational exposure limit (OEL) of 30 mg m(-3) when the drilling fluid temperature was ≥50°C. The practice of testing compliance of oil vapour exposure from drilling fluids systems containing base oils with viscosity of ≤2.0 mm(2) s(-1) at 40°C against the Norwegian oil vapour OEL is questioned since these base oils are very similar to white spirit. To reduce exposures, relevant technical control measures in this area are to cool the drilling fluid <50°C before it enters the shale shaker units, enclose shale shakers and related equipment, in addition to careful consideration of which fluid system to use.

Testing for Soluble ST2 in Heart Failure Patients: Reliability of a Point of Care Method.

PubMed

Gruson, Damien; Ferracin, Benjamin; Ahn, Sylvie A; Rousseau, Michel F

2017-01-01

Our objective was to determine soluble ST2 (sST2) concentrations in heart failure (HF) patients with a point-of-care (POCT) assay. sST2 levels were measured in 71 HF patients with both POCT and ELISA methods. The concentrations of sST2 were correlated to HF severity and to some established biomarkers of cardiovascular risk. sST2 levels measured with the ASPECT-PLUS POCT method were significantly correlated with the comparison ELISA assay (r = 0.94, p < 0.01) and were related to HF severity. Levels of sST2 measured with the POCT assay were significantly correlated to NT-proBNP (r = 0.57, p < 0.001), BNP (r = 0.75, p < 0.001), Galectin-3 (r = 0.40, p < 0.01) and PTH (1-84) (r = 0.39, p < 0.01). POCT and ELISA methods for sST2 testing were significantly correlated, and our results confirmed also the clinical reliability of the sST2 POCT assay. Furthermore, the POCT method allows a faster delivery of results to physicians.

Toxicity and physiological effects of brominated flame retardant PBDE-47 on two life stages of grass shrimp, Palaemonetes pugio.

PubMed

Key, Peter B; Chung, Katy W; Hoguet, Jennifer; Shaddrix, Brian; Fulton, Michael H

2008-07-25

This study examined the effects of a polybrominated diphenyl ether (PBDE) compound, PBDE-47, on adult and larval stages of the estuarine grass shrimp (Palaemonetes pugio). The 96-h LC50 test resulted in an estimate of 23.60 microg/L (95% confidence interval=14.51-38.37 microg/L) for larval shrimp. Adult shrimp had a higher 96-h LC50 of 78.07 microg/L (95% CI=65.1-93.63 microg/L). Four physiological biomarkers glutathione (GSH), lipid peroxidation (LPx), cholesterol (CHL) and acetylcholinesterase (AChE) were then assessed to study the sublethal effects of PBDE-47 exposure. GSH, LPx and AChE levels in both adults and larvae were not affected by PBDE-47 at concentrations up to 50 microg/L for 96 h. CHL levels were elevated in adults and larvae at the lowest exposure concentrations tested, but significant differences were found only in adult exposures. Effects associated with PBDE-47 aqueous exposures were observed at levels well above those reported in the environment.

Experimental study of effectiveness of four radon mitigation solutions, based on underground depressurization, tested in prototype housing built in a high radon area in Spain.

PubMed

Frutos Vázquez, Borja; Olaya Adán, Manuel; Quindós Poncela, Luis Santiago; Sainz Fernandez, Carlos; Fuente Merino, Ismael

2011-04-01

The present paper discusses the results of an empirical study of four approaches to reducing indoor radon concentrations based on depressurization techniques in underground sumps. The experiments were conducted in prototype housing built in an area of Spain where the average radon concentration at a depth of 1 m is 250 kBq m(-3). Sump effectiveness was analysed in two locations: underneath the basement, which involved cutting openings into the foundation, ground storey and roof slabs, and outside the basement walls, which entailed digging a pit alongside the building exterior. The effectiveness of both sumps was likewise tested with passive and forced ventilation methods. The systems proved to be highly efficient, lowering radon levels by 91-99%, except in the solution involving passive ventilation and the outside sump, where radon levels were reduced by 53-55%. At wind speeds of over 8 m/s, however, passive ventilation across an outside sump lowered radon levels by 95% due to a Venturi effect induced drop in pressure. Copyright © 2011 Elsevier Ltd. All rights reserved.

The relationship between proton pump inhibitor use and serum magnesium concentration among hemodialysis patients: a cross-sectional study.

PubMed

Misra, Paraish S; Alam, Ahsan; Lipman, Mark L; Nessim, Sharon J

2015-08-13

Observational data suggest that serum magnesium (Mg) concentration is inversely related to vascular calcification and hyperparathyroidism among patients with end-stage renal disease (ESRD). In recent years, there have been several case reports of hypomagnesemia due to use of proton-pump inhibitors (PPI), with the hypomagnesemia attributed to inappropriate gastrointestinal (GI) Mg loss. We hypothesized that the tendency to GI Mg loss is more common than is currently reported. Since patients with ESRD have little to no renal Mg loss to affect serum Mg concentration, dialysis patients are an interesting population in whom to study the relationship between PPI use and serum Mg levels. Using a single-center cross-sectional design, we studied 155 prevalent hemodialysis (HD) patients. Serum Mg concentration for each patient was determined based on the mean of 3 consecutive serum Mg levels drawn at 6 week intervals. PPI use at the time of the blood tests was documented. The relationship between PPI use and Mg concentration was determined in unadjusted analyses, as well as after adjustment for age, gender, race, cause of ESRD, diabetes, time on HD and dialysate Mg concentration. 55 % of patients were on PPIs at the time of the study. The majority of patients (62 %) used a dialysate Mg (in mmol/L) of 0.5, and the remainder (38 %) used a dialysate Mg of 0.375. Serum Mg levels were significantly lower among PPI users vs. non-users (0.93 vs. 1.02 mmol/L, p < 0.001). This finding persisted after stratifying for dialysate Mg concentration, and after multivariable adjustment (p < 0.001). In addition, more PPI users vs. non-users had a Mg level < 1 mmol/L (79 % vs. 43 %) and a Mg level < 0.8 mmol/L (16 % vs. 4 %). There was a non-significant trend toward increased time on PPI being associated with lower serum Mg levels (p = 0.067). Among HD patients, PPI users have lower serum Mg levels as compared with non-users. Further research is required to determine whether the magnitude of change in Mg levels among PPI users is associated with adverse outcomes.

A pilot study using scripted ventilation conditions to identify key factors affecting indoor pollutant concentration and air exchange rate in a residence.

PubMed

Johnson, Ted; Myers, Jeffrey; Kelly, Thomas; Wisbith, Anthony; Ollison, Will

2004-01-01

A pilot study was conducted using an occupied, single-family test house in Columbus, OH, to determine whether a script-based protocol could be used to obtain data useful in identifying the key factors affecting air-exchange rate (AER) and the relationship between indoor and outdoor concentrations of selected traffic-related air pollutants. The test script called for hourly changes to elements of the test house considered likely to influence air flow and AER, including the position (open or closed) of each window and door and the operation (on/off) of the furnace, air conditioner, and ceiling fans. The script was implemented over a 3-day period (January 30-February 1, 2002) during which technicians collected hourly-average data for AER, indoor, and outdoor air concentrations for six pollutants (benzene, formaldehyde (HCHO), polycyclic aromatic hydrocarbons (PAH), carbon monoxide (CO), nitric oxide (NO), and nitrogen oxides (NO(x))), and selected meteorological variables. Consistent with expectations, AER tended to increase with the number of open exterior windows and doors. The 39 AER values measured during the study when all exterior doors and windows were closed varied from 0.36 to 2.29 h(-1) with a geometric mean (GM) of 0.77 h(-1) and a geometric standard deviation (GSD) of 1.435. The 27 AER values measured when at least one exterior door or window was opened varied from 0.50 to 15.8 h(-1) with a GM of 1.98 h(-1) and a GSD of 1.902. AER was also affected by temperature and wind speed, most noticeably when exterior windows and doors were closed. Results of a series of stepwise linear regression analyses suggest that (1) outdoor pollutant concentration and (2) indoor pollutant concentration during the preceding hour were the "variables of choice" for predicting indoor pollutant concentration in the test house under the conditions of this study. Depending on the pollutant and ventilation conditions, one or more of the following variables produced a small, but significant increase in the explained variance (R(2)-value) of the regression equations: AER, number and location of apertures, wind speed, air-conditioning operation, indoor temperature, outdoor temperature, and relative humidity. The indoor concentrations of CO, PAH, NO, and NO(x) were highly correlated with the corresponding outdoor concentrations. The indoor benzene concentrations showed only moderate correlation with outdoor benzene levels, possibly due to a weak indoor source. Indoor formaldehyde concentrations always exceeded outdoor levels, and the correlation between indoor and outdoor concentrations was not statistically significant, indicating the presence of a strong indoor source.

Characterizing ultrafine particles and other air pollutants in and around school buses.

PubMed

Zhu, Yifang; Zhang, Qunfang

2014-03-01

Increasing evidence has demonstrated toxic effects of ultrafine particles (UFP*, diameter < 100 nm). Children are particularly at risk because of their immature respiratory systems and higher breathing rates per body mass. This study aimed to characterize UFP, PM2.5 (particulate matter < or = 2.5 microm in aerodynamic diameter), and other vehicular-emitted pollutants in and around school buses. Four sub-studies were conducted, including: 1. On-road tests to measure in-cabin air pollutant levels while school buses were being driven; 2. Idling tests to determine the contributions of tailpipe emissions from idling school buses to air pollutant levels in and around school buses under different scenarios; 3. Retrofit tests to evaluate the performance of two retrofit systems, a diesel oxidation catalyst (DOC) muffler and a crankcase filtration system (CFS), on reducing tailpipe emissions and in-cabin air pollutant concentrations under idling and driving conditions; and 4. High efficiency particulate air (HEPA) filter air purifier tests to evaluate the effectiveness of in-cabin filtration. In total, 24 school buses were employed to cover a wide range of school buses commonly used in the United States. Real-time air quality measurements included particle number concentration (PNC), fine and UFP size distribution in the size range 7.6-289 nm, PM2.5 mass concentration, black carbon (BC) concentration, and carbon monoxide (CO) and carbon dioxide (CO2) concentrations. For in-cabin measurements, instruments were placed on a platform secured to the rear seats inside the school buses. For all other tests, a second set of instruments was deployed to simultaneously measure the ambient air pollutant levels. For tailpipe emission measurements, the exhaust was diluted and then measured by instruments identical to those used for the in-cabin measurements. The results show that when driving on roads, in-cabin PNC, fine and UFP size distribution, PM2.5, BC, and CO varied by engine age, window position, driving speed, driving route, and operating conditions. Emissions from idling school buses increased the PNC close to the tailpipe by a factor of up to 26.0. Under some circumstances, tailpipe emissions of idling school buses increased the in-cabin PNC by factors ranging from 1.2 to 5.8 in the 10-30 nm particle size range. Retrofit systems significantly reduced the tailpipe emissions of idling school buses. With both DOC and CFS installed, PNC in tailpipe emissions dropped by 20%-94%. No unequivocal decrease was observed for in-cabin air pollutants after retrofitting. The operation of the air conditioning (AC) unit and the pollutant concentrations in the surrounding ambient air played more important roles than retrofit technologies in determining in-cabin air quality. The use of a HEPA air purifier removed up to 50% of in-cabin particles. Because each sub-study tested only a subset of the 24 school buses, the results should be seen as more exploratory than definitive.

Somatotype and stress hormone levels in young soccer players.

PubMed

Handziska, E; Handziski, Z; Gjorgoski, I; Dalip, M

2015-11-01

The relationship between somatotype and cortisol and adrenocorticotropic (ACTH) hormone concentrations at rest or after exercise in adolescent soccer players at different time points throughout a soccer season is not understood. Therefore, the aim of this study was to examine the relationship between somatotype and cortisol and ACTH concentrations at rest and after exercise in adolescent soccer players at different time points during a soccer season. During the first 4 months of the soccer season, 47 soccer players (between 15-17 years of age) were tested at three different time points including at baseline, after 6 weeks, and at the end of 4 months. Testing included anaerobic threshold (AnT, km/h) and maximal speed of running (Max, km/h) were measured with Conconi protocol on treadmill. Before and after a maximal exercise Test, plasma levels of cortisol (ug/dL) and ACTH (pg/ml) were assessed by chemiluminometry enzyme amplificated method. Heath-Carter anthropometric somatotype model was used to determine 13 elements of somatotype. Descriptive statistics and multiple regression were used for statistical analysis (P<0.05). Body composition and AnT were not significantly different between each time point of testing. The mesomorph-ectomorph (N.=21), balanced mesomorph (N.=8) and balanced ectomorph (N.=7) were the most frequent somatotypes. There were significant decrements of cortisol plasma levels (at rest 33.4%; after test 27.46%), with insignificant changes of ACTH plasma levels, after 6 weeks of preparation phase and after finishing of half season, at rest and after maximal treadmill test. There were significant correlation between ACTH levels at rest (R=0.44; P<0.01) and some somatotypes (mesomorph endomorph, central and balanced endomorph) and ACTH levels after maximal exercise test (R=0.36; P<0.05) and balanced ectomorph and endomorph mesomorph. There were significant correlation between cortisol levels after maximal exercise test at the beginning of training process (R=0.59; P<0.01) and some somatotypes (mesomorph ectomorph, mesomorph endomorph, balanced endomorph and endomorph mesomorph) and after the finishing of training process (R=0.62; P<0.01) and some somatotypes (central, balanced ectomorph and mesomorph ectomorph). The significant decreases of cortisol plasma levels during soccer training process could indicate a stagnation of training process, accordingly with insignificant changes of AnT. The significant correlations of some somatotypes with stress hormonal responses could only suggest that the somatotype characteristics of young soccer players could be of interest in process of selection and planning of soccer training process with an essential need for more studies.

The development of a volatile organics concentrator for use in monitoring Space Station water quality

NASA Technical Reports Server (NTRS)

Bodek, Itamar; Ehntholt, Daniel J.; Stolki, Thomas J.; Valentine, James R.; Trabanino, Rudy; Webb, Johanna V.; Sauer, Richard L.

1991-01-01

A breadboard concept of a volatile organics concentrator (VOC) is manufactured and tested for optimized water-quality analysis in a space environment. The VOC system is attached to a gas chromatograph/mass spectrometer to analyze the volatile chemicals relevant to the operation of Space Station Freedom. The preliminary tests include: (1) comparisons with analyses based on direct on-column injections of standards; (2) analyses of iodinated volatile organics; (3) comparisons of nitrogen vs helium as the chromatography carrier gas; and (4) measurements of collection efficiency. The VOC can analyze EPA method-624 analytes at comparable detection using flame-ionization detection and can analyze volatile iodinated compounds. The breadboard has good reproducibility and can use nitrogen as a carrier gas; good results are noted for the collection and concentration levels and for water removal.

Interactive effects of p,p'-dichlorodiphenyldichloroethylene and methoxychlor on hormone synthesis in largemouth bass ovarian cultures.

PubMed

Borgert, Christopher J; Gross, Timothy S; Guiney, Patrick D; Osimitz, Tomas G; Price, Bertram; Wells, Christopher

2004-08-01

p,p'-Dichlorodiphenyldichloroethylene (DDE) and methoxychlor were tested alone and in combination to assess the similarity of their actions on hormone synthesis in gonadal tissue from largemouth bass (Micropterus salmoides floridanus), a species whose reproductive fitness has relevance to ecosystem health in Florida (USA). Gonads were harvested from adult female bass (age, two to three years) during the peak reproductive season (January-May), minced, and incubated in culture medium with or without test agents for 48 h. Duplicates of each treatment were performed in each of three experiments using tissue from a different female. Both 17beta-estradiol and testosterone were measured in aliquots of culture medium by validated radioimmunoassay procedures. Dose-response relationships of individual agents were characterized over a 6-log concentration range (1 X 10(-2) to 1 X 10(4) ppb). Both DDE and methoxychlor, tested individually, produced a dose-dependent decrease in testosterone levels. 17beta-Estradiol levels were unaffected. Mixtures of the agents were tested at all concentration combinations of 0.01, 1, 100, and 10,000 ppb in culture medium. Statistical tests indicated that of 16 dose combinations tested, 15 were antagonistic, and only 1 was additive based on the Loewe additivity model of no interaction. These results imply that methoxychlor and DDE inhibit testosterone production by different mechanisms in bass ovaries.

Design and Testing of Trace Contaminant Injection and Monitoring Systems

NASA Technical Reports Server (NTRS)

Broerman, Craig D.; Sweterlitsch, Jeff

2009-01-01

In support of the Carbon dioxide And Moisture Removal Amine Swing-bed (CAMRAS) testing, a contaminant injection system as well as a contaminant monitoring system has been developed by the Johnson Space Center Air Revitalization Systems (JSC-ARS) team. The contaminant injection system has been designed to provide trace level concentrations of contaminants generated by humans in a closed environment during space flight missions. The contaminant injection system continuously injects contaminants from three gas cylinders, two liquid reservoirs and three permeation ovens. The contaminant monitoring system has been designed to provide real time gas analysis with accurate flow, humidity and gas concentration measurements for collection during test. The contaminant monitoring system consists of an analytical real time gas analyzer, a carbon monoxide sensor, and an analyzer for ammonia and water vapor.

Antimicrobial effects of Citrus sinensis peel extracts against dental caries bacteria: An in vitro study

PubMed Central

Shetty, Sapna B.; Mahin-Syed-Ismail, Prabu; Varghese, Shaji; Thomas-George, Bibin; Kandathil- Thajuraj, Pathinettam; Baby, Deepak; Haleem, Shaista; Sreedhar, Sreeja

2016-01-01

Background Ethnomedicine is gaining admiration since years but still there is abundant medicinal flora which is unrevealed through research. The study was conducted to assess the in vitro antimicrobial potential and also determine the minimum inhibitory concentration (MIC) of Citrus sinensis peel extracts with a view of searching a novel extract as a remedy for dental caries pathogens. Material and Methods Aqueous and ethanol (cold and hot) extracts prepared from peel of Citrus sinensis were screened for in vitro antimicrobial activity against Streptococcus mutans and Lactobacillus acidophilus, using agar well diffusion method. The lowest concentration of every extract considered as the minimal inhibitory concentration (MIC) values were determined for both test organisms. One way ANOVA with Post Hoc Bonferroni test was applied for statistical analysis. Confidence level and level of significance were set at 95% and 5% respectively. Results Dental caries pathogens were inhibited most by hot ethanolic extract of Citrus sinensispeel followed by cold ethanolic extract. Aqueous extracts were effective at very high concentrations. Minimum inhibitory concentration of hot and cold ethanolic extracts of Citrus sinensis peel ranged between 12-15 mg/ml against both the dental caries pathogens. Conclusions Citrus sinensispeels extract was found to be effective against dental caries pathogens and contain compounds with therapeutic potential. Nevertheless, clinical trials on the effect of these plants are essential before advocating large-scale therapy. Key words:Agar well diffusion, antimicrobial activity, dental caries, Streptococcus mutans, Lactobacillus acidophilus. PMID:26855710

Environmental contaminants and chromosomal damage associated with beak deformities in a resident North American passerine

USGS Publications Warehouse

Handel, Colleen M.; Van Hemert, Caroline R.

2015-01-01

A large cluster of beak abnormalities among black-capped chickadees (Poecile atricapillus) in Alaska raised concern about underlying environmental factors in this region. Metals and trace elements, organochlorine pesticides, polychlorinated biphenyls (PCBs), and polychlorinated dibenzo-dioxins and polychlorinated dibenzofurans (PCDD-Fs) were analyzed in adults, nestlings, and eggs of the affected population; local bird seed was also tested for organochlorine pesticides. The results offered no support for the hypothesis that selenium or any other inorganic element was responsible for beak deformities among chickadees, but some evidence that organochlorine compounds may be contributing factors. Adults with beak deformities had an elevated level of chromosomal damage, which was correlated with lipid level and concentrations of several organochlorine compounds. Multivariate analyses of pesticides and PCBs did not distinguish abnormal from normal adults, but subsequent univariate analysis demonstrated higher concentrations of heptachlor epoxide and PCB-123 in abnormal adults. Concentrations of all organochlorine compounds were low, and none is known to cause beak or keratin abnormalities. Patterns of PCB congener concentrations differed between nestlings with normal and abnormal parents. Eggs from clutches with low hatchability had higher concentrations of hexachlorobenzene and PCDD-Fs than those with high hatching success, and hexachlorobenzene was found in seeds. Additional testing for PCDD-Fs, polycyclic aromatic hydrocarbons, and other emerging contaminants, including brominated compounds, is needed to rule out environmental contaminants as a cause of beak deformities in chickadees in Alaska.

a Thermally Desorbable Miniature Passive Dosimeter for Organic Vapors

NASA Astrophysics Data System (ADS)

Gonzalez, Jesus Antonio

A thermally desorbable miniature passive dosimeter (MPD) for organic vapors has been developed in conformity with theoretical and practical aspects of passive dosimeter design. The device was optimized for low sample loadings resulting from short-term and/or low concentration level exposure. This was accomplished by the use of thermal desorption rather than solvent elution, which provided the GC method with significantly higher sensitivity. Laboratory evaluation of this device for factors critical to the performance of passive dosimeters using benzene as the test vapor included: desorption efficiency (97.2%), capacity (1400 ppm-min), sensitivity (7ng/sample or 0.06 ppmv for 15 minutes sampling) accuracy and precision, concentration level, environmental conditions (i.e., air face velocity, relative humidity) and sample stability during short (15 minutes) and long periods of time (15 days). This device has demonstrated that its overall accuracy meets NIOSH and OSHA requirements for a sampling and analytical method for the exposure concentration range of 0.1 to 50 ppm (v/v) and 15 minutes exposures. It was demonstrated that the MPD operates in accordance with theoretically predicted performance and should be adequate for short-term and/or low concentration exposure monitoring of organic vapors in the workplace. In addition a dynamic vapor exposure evaluation system for passive dosimeters have been validated using benzene as the test vapor. The system is capable of generating well defined short-square wave concentration profiles suitable for the evaluation of passive dosimeters for ceiling exposure monitoring.

Cognitive impairment related changes in the elemental concentration in the brain of old rat

NASA Astrophysics Data System (ADS)

Serpa, R. F. B.; de Jesus, E. F. O.; Anjos, M. J.; Lopes, R. T.; do Carmo, M. G. T.; Rocha, M. S.; Rodrigues, L. C.; Moreira, S.; Martinez, A. M. B.

2006-11-01

In order to evaluate the elemental concentration as a function of learning and memory deficiency, six different structures of the brain were analyzed by total reflection X-ray fluorescence spectrometry with synchrotron radiation (SR-TXRF). To evaluate the cognitive processes, the animals were tested in an adaptation of the Morris water maze. After the test, the animals were divided into two groups: cognitively healthy (control group) and cognitively impaired. The measurements were carried out at XRF beam line at Light Synchrotron Brazilian laboratory, Campinas, Brazil. The following elements were identified: Al, P, S, Cl, K, Ca, Ti, Cr, Fe, Cu, Zn, Br and Rb. K concentration was higher in all regions of the brain studied for control group than the cognitively impaired group. Moreover, the control group presented higher levels for P and Fe in the entorhinal cortex, in the temporal cortex (only P), in the hypothalamus and in the thalamus, than the cognitively impaired group. Br concentration in the animals which presented cognitive impairment was three times larger in the hypothalamus and thalamus, twice larger in temporal cortex and higher in visual cortex than the cognitively healthy group. Cu was more remarkable in the hippocampus and hypothalamus from the animals with cognitive impairment than the control group. We observed that the cognitively impaired group presented highest concentrations of Br and Cu in certain areas than the control group, on the other hand, this group presented highest levels of K for all brain areas studied.

Indirect effects of elevated body mass index on memory performance through altered cerebral metabolite concentrations.

PubMed

Gonzales, Mitzi M; Tarumi, Takashi; Eagan, Danielle E; Tanaka, Hirofumi; Vaghasia, Miral; Haley, Andreana P

2012-09-01

Elevated body mass index (BMI) at midlife is associated with increased risk of cognitive decline in later life. The goal of the current study was to assess mechanisms of early brain vulnerability by examining if higher BMI at midlife affects current cognitive performance through alterations in cerebral neurochemistry. Fifty-five participants, aged 40 to 60 years, underwent neuropsychological testing, health screen, and proton magnetic resonance spectroscopy examining N-acetylaspartate, creatine (Cr), myo-inositol (mI), choline, and glutamate concentrations in occipitoparietal gray matter. Concentrations of N-acetylaspartate, choline, mI, and glutamate were calculated as a ratio over Cr and examined in relation to BMI using multivariate regression analyses. Structural equation modeling was used to determine if BMI had an indirect effect on cognition through cerebral metabolite levels. Higher BMI was associated with elevations in mI/Cr (F(5,45) = 3.843, p = .006, β = 0.444, p = .002), independent of age, sex, fasting glucose levels, and systolic blood pressure. Moreover, a χ(2) difference test of the direct and indirect structural equation models revealed that BMI had an indirect effect on global cognitive performance (Δχ(2) = 19.939, df = 2, p < .001). Subsequent follow-up analyses revealed that this effect was specific to memory (Δχ(2) = 22.027, df = 2, p < .001). Higher BMI was associated with elevations in mI/Cr concentrations in the occipitoparietal gray matter and indirectly related to poorer memory performance through mI/Cr levels, potentially implicating plasma hypertonicity and neuroinflammation as mechanisms underlying obesity-related brain vulnerability.

Effects of dietary biotin supplementation on glucagon production, secretion, and action.

PubMed

Lazo-de-la-Vega-Monroy, Maria-Luisa; Larrieta, Elena; Tixi-Verdugo, Wilma; Ramírez-Mondragón, Rafael; Hernández-Araiza, Ileana; German, Michael S; Fernandez-Mejia, Cristina

Despite increasing evidence that pharmacologic concentrations of biotin modify glucose metabolism, to our knowledge there have not been any studies addressing the effects of biotin supplementation on glucagon production and secretion, considering glucagon is one of the major hormones in maintaining glucose homeostasis. The aim of this study was to investigate the effects of dietary biotin supplementation on glucagon expression, secretion, and action. Male BALB/cAnN Hsd mice were fed a control or a biotin-supplemented diet (1.76 or 97.7 mg biotin/kg diet) for 8 wk postweaning. Glucagon gene mRNA expression was measured by the real-time polymerase chain reaction. Glucagon secretion was assessed in isolated islets and by glucagon concentration in plasma. Glucagon action was evaluated by glucagon tolerance tests, phosphoenolpyruvate carboxykinase (Pck1) mRNA expression, and glycogen degradation. Compared with the control group, glucagon mRNA and secretion were increased from the islets of the biotin-supplemented group. Fasting plasma glucagon levels were higher, but no differences between the groups were observed in nonfasting glucagon levels. Despite the elevated fasting glucagon levels, no differences were found in fasting blood glucose concentrations, fasting/fasting-refeeding glucagon tolerance tests, glycogen content and degradation, or mRNA expression of the hepatic gluconeogenic rate-limiting enzyme, Pck1. These results demonstrated that dietary biotin supplementation increased glucagon expression and secretion without affecting fasting blood glucose concentrations or glucagon tolerance and provided new insights into the effect of biotin supplementation on glucagon production and action. Copyright © 2017 Elsevier Inc. All rights reserved.

Measurement of volatile organic compounds inside automobiles.

PubMed

Fedoruk, Marion J; Kerger, Brent D

2003-01-01

The objective of the current study was to evaluate the types and concentrations of volatile organic compounds (VOCs) in the passenger cabin of selected sedan automobiles under static (parked, unventilated) and specified conditions of operation (i.e., driving the vehicle using air conditioning alone, vent mode alone, or driver's window half open). Data were collected on five different passenger sedan vehicles from three major automobile manufacturers. Airborne concentrations were assessed using 90-min time-weighted average (TWA) samples under U.S. Environmental Protection Agency (USEPA) Method IP-1B to assess individual VOC compounds and total VOCs (TVOCs) calibrated to toluene. Static vehicle testing demonstrated TVOC levels of approximately 400-800 microg/m(3) at warm interior vehicle temperatures (approximately 80 degrees F), whereas TVOCs at least fivefold higher were observed under extreme heat conditions (e.g., up to 145 degrees F). The profile of most prevalent individual VOC compounds varied considerably according to vehicle brand, age, and interior temperature tested, with predominant compounds including styrene, toluene, and 8- to 12-carbon VOCs. TVOC levels under varied operating conditions (and ventilation) were generally four- to eightfold lower (at approximately 50-160 microg/m(3)) than the static vehicle measurements under warm conditions, with the lowest measured levels generally observed in the trials with the driver's window half open. These data indicate that while relatively high concentrations of certain VOCs can be measured inside static vehicles under extreme heat conditions, normal modes of operation rapidly reduce the inside-vehicle VOC concentrations even when the air conditioning is set on recirculation mode.

Effect of anaesthetics MS-222 and clove oil on blood biochemical parameters of juvenile Siberian sturgeon (Acipenser baerii)

USGS Publications Warehouse

Feng, G.; Zhuang, P.; Zhang, L.; Kynard, B.; Shi, X.; Duan, M.; Liu, J.; Huang, X.

2011-01-01

The effects of MS-222 and clove oil on blood biochemical parameters of juvenile Siberian sturgeon (Acipenser baerii) were studied. MS-222 caused higher glucose (GLU) concentrations in anaesthetic test groups than for the control group. Triglyceride (TGL) concentrations of fish in the 140 and 160mgL-1 groups were also significantly higher than those of other groups. Alanine aminotransferase (ALT) activity in the 140mgL-1 group was significantly higher than the level in 80, 100 and 120mgL-1 groups. Aspartate aminotransferase (AST) activity in the 140mgL-1 group was significantly higher than those in the 100 and 120mgL-1 groups. Levels of total protein (TP), cholesterol (CHOL) and alkaline phosphatase (ALP) in anaesthetic test groups were not significantly influenced by MS-222. Clove oil did not have significant effects on levels of GLU, TP, CHOL, ALT and ALP. TGL concentration of fish exposed to 180mgL-1 clove oil was significantly higher than those of the rest anaesthetic groups. AST activities of fish exposed to 120, 150 and 180mgL-1 were significantly higher than those of 60 and 90mgL-1. Overall, TGL and AST could be potentially used as indicators of anaesthetic stress for juvenile Siberian sturgeon. Based on blood biochemical parameters, the appropriate anaesthetic concentrations of MS-222 and clove oil were 80-120mgL-1 and 60-90mgL-1, respectively. Clove oil was a promising alternative to MS-222. ?? 2011 Blackwell Verlag, Berlin.

Influence of artificial sweetener on human blood glucose concentration.

PubMed

Skokan, Ilse; Endler, P Christian; Wulkersdorfer, Beatrix; Magometschnigg, Dieter; Spranger, Heinz

2007-10-05

Artificial sweeteners, such as saccharin or cyclamic acid are synthetically manufactured sweetenings. Known for their low energetic value they serve especially diabetic and adipose patients as sugar substitutes. It has been hypothesized that the substitution of sugar with artificial sweeteners may induce a decrease of the blood glucose. The aim of this study was to determine the reliability of this hypothesis by comparing the influence of regular table sugar and artificial sweeteners on the blood glucose concentration. In this pilot-study 16 patients were included suffering from adiposity, pre-diabetes and hypertension. In the sense of a cross-over design, three test trials were performed at intervals of several weeks. Each trial was followed by a test free interval. Within one test trial each patient consumed 150 ml test solution (water) that contained either 6 g of table sugar ("Kandisin") with sweetener free serving as control group. Tests were performed within 1 hr after lunch to ensure conditions comparable to patients having a desert. Every participant had to determine their blood glucose concentration immediately before and 5, 15, 30 and 60 minutes after the intake of the test solution. For statistics an analysis of variance was performed. The data showed no significant changes in the blood glucose concentration. Neither the application of sugar (F(4;60) = 1.645; p = .175) nor the consumption of an artificial sweetener (F(2.068;31.023) = 1.551; p > .05) caused significant fluctuations in the blood sugar levels. Over a time frame of 60 minutes in the control group a significant decrease of the blood sugar concentration was found (F(2.457;36.849) = 4.005; p = .020) as a physiological reaction during lunch digestion.

Comparison of leaching characteristics of heavy metals in APC residue from an MSW incinerator using various extraction methods.

PubMed

Chiang, Kung-Yuh; Tsai, Chen-Chiu; Wang, Kuen-Sheng

2009-01-01

This study investigates four extraction methods (water extraction, toxicity characteristics leaching procedure (TCLP), modified TCLP with pH control, and sequential chemical extraction (SCE)), each representing different liquid-to-solid (L/S) ratios, pH controls, and types of leachant, and their effects on the leaching concentration of heavy metals in municipal solid waste (MSW) incinerator air pollution control (APC) residue. The results indicated that for extraction with distilled water, the heavy metal leaching concentration (mg/l) decreased with L/S ratio, but the amount of heavy metal released (AHMR), defined as the leached amount of heavy metals to the weight of the tested sample (mg/kg), increased with an increase in L/S ratio, in the range of 2-100. The results also showed that both the leaching concentration and the amount of released metals were strongly pH-dependent in the TCLP and modified TCLP tests. In the case of pHs lower than 6.5, the leaching concentrations of Cd, Pb, Cu, Zn, and Cr decreased with an increase in pH. As pH increased higher than 6.5, Cr and Zn were almost insoluble. Meanwhile, Cd and Cu also showed a similar trend but at pHs of 8.5 and 7.5, respectively. Due to the nature of amphoteric elements, in the case of pHs higher than 7, the Pb leaching concentration increased with increasing pH. In modified TCLP tests with the pH value controlled at the same level as in the SCE test, the heavy metal speciation approached the extractable carbonate bound fraction by the SCE. Both amounts of targeted metals leached from the SCE and modified TCLP tests were much higher than those for the regular TCLP and water extraction tests.

Identification of nitrate long term trends in Loire-Brittany river district (France) in connection with hydrogeological contexts, agricultural practices and water table level variations

NASA Astrophysics Data System (ADS)

Lopez, B.; Baran, N.; Bourgine, B.; Ratheau, D.

2009-04-01

The European Union (EU) has adopted directives requiring that Member States take measures to reach a "good" chemical status of water resources by the year 2015 (Water Framework Directive: WFD). Alongside, the Nitrates Directives (91/676/EEC) aims at controlling nitrogen pollution and requires Member States to identify groundwaters that contain more than 50 mg NO3 L-1 or could exceed this limit if preventive measures are not taken. In order to achieve these environmental objectives in the Loire-Brittany river basin, or to justify the non achievement of these objectives, a large dataset of nitrate concentrations (117.056 raw data distributed on 7.341 time-series) and water table level time-series (1.371.655 data distributed on 511 piezometers) is analysed from 1945 to 2007. The 156.700 sq km Loire-Brittany river basin shows various hydrogeological contexts, ranging from sedimentary aquifers to basement ones, with a few volcanic-rock aquifers. The knowledge of the evolution of agricultural practices is important in such a study and, even if this information is not locally available, agricultural practices have globally changed since the 1991 Nitrates Directives. The detailed dataset available for the Loire-Brittany basin aquifers is used to evaluate tools and to propose efficient methodologies for identifying and quantifying past and current trends in nitrate concentrations. Therefore, the challenge of this study is to propose a global and integrated approach which allows nitrate trend identifications for the whole Loire-Brittany river basin. The temporal piezometric behaviour of each aquifer is defined using geostatistical analyse of water table level time-series. This method requires the calculation of an experimental temporal variogram that can be fitted with a theoretical model valid for a large time range. Identification of contrasted behaviours (short term, annual or pluriannual water table fluctuations) allows a systematic classification of the Loire-Brittany superficial aquifers. The nitrate dataset shows too many irregularities to employ traditional time-series approaches such as linear regression trend tests. The non-parametric Mann-Kendall (MK) test is a robust statistical trend detection test that does not require verification of the normality of the dataset (Aguilar et al, 2007). Moreover, this test seems appropriate since it is less sensitive to missing or outlier data than a simple linear regression test. As the MK test can only detect monotonic trends, and as already done by Stuart et al., (2007) and Broers and Van der Grift (2004), the trend analyses are decennially partitioned in order to identify possible trend reversals for the studied period for each observation point. The trend identification is then spatialized by the use of the Kendall Regional (KR) test on homogenous zones characterized by their geology, their agricultural practices and their piezometric behaviour. The KR test, previously used by Frans and Helsel (2005) in the Columbia Basin Ground Water context, is quite similar to the MK test and consists of the creation of virtual regional boreholes using networks of boreholes located in the homogenous zones. This test allows the identification of regional monotonic trends, even in the zones where nitrate time-series are too small to detect significant trend per observation point. The MK test results show significant upward trends in nitrate concentrations in the Loire-Brittany superficial aquifers when the test is computed on the 1945-2007 period. However, the decennial MK test shows different behaviours at smaller time scale. Some zones are characterized by a constant and significant increase in nitrate concentrations since 1945 (North-East of Brittany, North of Beauce) whereas others show a trend reversal (South of Brittany, Callovo-Oxfordian marls between Le Mans and Alençon, under covered Jurassic limestone around Poitiers). Furthermore, some rare zones show an increase in nitrate concentrations that follow a significant downward trend period (Orléans). In the nineties, a transition period may have occurred with a higher proportion of upward than downward trends (82 % against 7 % respectively) for the 1980-1990 period and a lower proportion of upward than downward trends for the 2000-2007 period (37 % against 51 % respectively). Combined with the analyse of the current groundwater nitrate concentrations, the KR test reveals zones where trends in nitrate concentrations have been significantly raising with high nitrate current mean values (> 50 mg NO3 L-1). On the other hand, some zones show a significant regional downward trend since 1995 and low current nitrate concentrations (< 20 mg NO3 L-1). Causes of trend reversals cannot be determined by the MK and KR statistical trend analyses, but the cross analyse of nitrate and water table level time-series gives a hint of a positive correlation between these two variables. Evolution of nitrate concentrations in superficial aquifers may thus depend on a combined effect of changes in both agricultural practices and evolution of water table levels linked with climatic context. References Aguilar J.B., Orban P., Dassargues A., Brouyère S., (2007) - Identification of groundwater quality trends in a chalk aquifer threatened by intensive agriculture in Belgium. Hydrogeology journal 15: 1615-1627. Broers H.P., van der Grift B., (2004) - Regional monitoring of temporal changes in groundwater quality. Journal of hydrology 296: 192-220. Frans L.M., Helsel D.R. (2005) - Evaluating regional trends in ground water nitrate concentrations of the Columbia Basin Ground Water management Area, Washington. U.S. Geological Survey Scientific Investigations Report 2005-5078, 7p. Stuart M.E., Chilton P.J., Kiniiburgh D.G., Cooper D.M., (2007) - Screening for long-term trends in groundwater nitrate monitoring data. Quaterly Journal of Engineering Geology and Hydrogeology, 40: 361-376. Funding The study was funded by the Loire-Brittany River Basin Agency and from proper BRGM funds.

Dual Mode NOx Sensor: Measuring Both the Accumulated Amount and Instantaneous Level at Low Concentrations

PubMed Central

Groß, Andrea; Beulertz, Gregor; Marr, Isabella; Kubinski, David J.; Visser, Jaco H.; Moos, Ralf

2012-01-01

The accumulating-type (or integrating-type) NOx sensor principle offers two operation modes to measure low levels of NOx: The direct signal gives the total amount dosed over a time interval and its derivative the instantaneous concentration. With a linear sensor response, no baseline drift, and both response times and recovery times in the range of the gas exchange time of the test bench (5 to 7 s), the integrating sensor is well suited to reliably detect low levels of NOx. Experimental results are presented demonstrating the sensor’s integrating properties for the total amount detection and its sensitivity to both NO and to NO2. We also show the correlation between the derivative of the sensor signal and the known gas concentration. The long-term detection of NOx in the sub-ppm range (e.g., for air quality measurements) is discussed. Additionally, a self-adaption of the measurement range taking advantage of the temperature dependency of the sensitivity is addressed. PMID:22736980

[Chronic bone pain due to raised FGF23 production? The importance of determining phosphate levels].

PubMed

de Jongh, Renate T; Vervloet, Marc G; Bravenboer, Nathalie; Heijboer, Annemieke C; den Heijer, Martin; Lips, Paul

2013-01-01

Hypophosphatemia is an important finding in the evaluation of patients with chronic bone pain. Fibroblast-growth factor 23 (FGF23) plays a role in the differential diagnosis of hypophosphatemia. A 34-year-old man had progressive pain in both shoulders and hips due to hypophosphatemic osteomalacia. He had elevated FGF23 levels, induced by a FGF23-producing tumour in the right acetabulum. Thus, he had tumour-induced hypophosphatemic osteomalacia. A 50-year-old man had had bowed legs and joint pains since his youth due to osteomalacia. Several family members also had osteomalacia. His phosphate concentration was low. Genetic testing revealed a mutation on the PHEX gene which results in high FGF23 levels. Thus, he had X-linked hereditary hypophosphatemic osteomalacia. In patients with bone pain, the measurement of a phosphate concentration is important. In renal phosphate loss, the measurement of FGF23 is an important next step if parathormone concentrations are low or normal.

Trace metals in liver, skin and muscle of Lethrinus lentjan fish species in relation to body length and sex.

PubMed

Al-Yousuf, M H; El-Shahawi; Al-Ghais, S M

2000-07-10

A post-Gulf sea water pollution assessment program was carried out in the liver, skin and muscle tissues of the localized Lethrinus lentjan fish species [Family: Lethrinidae (Teleost)]. Monitoring the concentration of the major heavy metals at different sites along the western coast of the United Arab Emirates (UAE) on the Arabian Gulf was studied. The concentrations of Zn, Cu and Mn were found to follow the order: liver > skin > muscle while the cadmium level follows the sequence: liver > muscle > skin. The influence of fish sex and body length on the metal accumulation of those metals in the tested fish organs was critically investigated. The average metal concentrations in liver, skin and muscle of female fish were found to be higher than those found in the male fish. The detected metal levels were generally similar to previous pre-war, 1991 levels. The study concludes that the marine fish from the Arabian Gulf are comparatively clean and do not constitute a risk for human health.

Latex agglutination inhibition card test for gentamicin assay: clinical evaluation and comparison with radioimmunoassay and bioassay.

PubMed Central

Standiford, H C; Bernstein, D; Nipper, H C; Caplan, E; Tatem, B; Hall, J S; Reynolds, J

1981-01-01

Gentamicin levels were determined in 100 serum specimens by a new latex agglutination inhibition card test, a radioimmunoassay (RIA), and a bioassay. Correlation coefficients determined by linear regression analysis demonstrated that the levels obtained by the latex agglutination inhibition card test had a high degree of correlation with the RIA and could be performed much faster and more economically when processing small numbers of specimens. The bioassay had a slightly lower degree of correlation with both the RIA and the latex test and was adversely influenced by concurrently administered antibiotics which could not be eliminated by beta-lactamase. When measuring gentamicin concentrations above 2 micrograms/ml, the coefficient of variation was less than 14% for the latex agglutination assay compared with 15% for the bioassay and 12% for RIA. The latex agglutination inhibition card test is a rapid, accurate, specific, and reproducible method for monitoring gentamicin levels in patients and is particularly applicable for laboratories processing small numbers of specimens. PMID:7247384

Urine monitoring system failure analysis and operational verification test report

NASA Technical Reports Server (NTRS)

Glanfield, E. J.

1978-01-01

Failure analysis and testing of a prototype urine monitoring system (UMS) are reported. System performance was characterized by a regression formula developed from volume measurement test data. When the volume measurement test data. When the volume measurement data was imputted to the formula, the standard error of the estimate calculated using the regression formula was found to be within 1.524% of the mean of the mass of the input. System repeatability was found to be somewhat dependent upon the residual volume of the system and the evaporation of fluid from the separator. The evaporation rate was determined to be approximately 1cc/minute. The residual volume in the UMS was determined by measuring the concentration of LiCl in the flush water. Observed results indicated residual levels in the range of 9-10ml, however, results obtained during the flushing efficiency test indicated a residual level of approximately 20ml. It is recommended that the phase separator pumpout time be extended or the design modified to minimize the residual level.

Field Testing of Alternative Cookstove Performance in a Rural Setting of Western India

PubMed Central

Muralidharan, Veena; Sussan, Thomas E.; Limaye, Sneha; Koehler, Kirsten; Williams, D’Ann L.; Rule, Ana M.; Juvekar, Sanjay; Breysse, Patrick N.; Salvi, Sundeep; Biswal, Shyam

2015-01-01

Nearly three billion people use solid fuels for cooking and heating, which leads to extremely high levels of household air pollution and is a major cause of morbidity and mortality. Many stove manufacturers have developed alternative cookstoves (ACSs) that are aimed at reducing emissions and fuel consumption. Here, we tested a traditional clay chulha cookstove (TCS) and five commercially available ACSs, including both natural draft (Greenway Smart Stove, Envirofit PCS-1) and forced draft stoves (BioLite HomeStove, Philips Woodstove HD4012, and Eco-Chulha XXL), in a test kitchen in a rural village of western India. Compared to the TCS, the ACSs produced significant reductions in particulate matter less than 2.5 µm (PM2.5) and CO concentrations (Envirofit: 22%/16%, Greenway: 24%/42%, BioLite: 40%/35%, Philips: 66%/55% and Eco-Chulha: 61%/42%), which persisted after normalization for fuel consumption or useful energy. PM2.5 and CO concentrations were lower for forced draft stoves than natural draft stoves. Furthermore, the Philips and Eco-Chulha units exhibited higher cooking efficiency than the TCS. Despite significant reductions in concentrations, all ACSs failed to achieve PM2.5 levels that are considered safe by the World Health Organization (ACSs: 277–714 μg/m3 or 11–28 fold higher than the WHO recommendation of 25 μg/m3;). PMID:25654775

Inhibition of verocytotoxigenic Escherichia coli by antimicrobial peptides caseicin A and B and the factors affecting their antimicrobial activities.

PubMed

McDonnell, Mary J; Rivas, Lucia; Burgess, Catherine M; Fanning, Séamus; Duffy, Geraldine

2012-02-15

The antimic robial activities of caseicin A and B antimicrobial peptides (AMPs) were assessed against a selection of verocytotoxigenic Escherichia coli (VTEC) strains (n=11), other bacterial pathogenic and spoilage bacteria (n=7), using a model broth system. The ability of the AMPs to retain their antimicrobial activities against a strain of E. coli O157:H7 380-94 under various test conditions (pH, temperature, water activity, sodium chloride concentrations, inoculum size and the presence of competitive microflora) was assessed and the minimum inhibitory concentrations (MIC) and number of surviving E. coli O157:H7 calculated. The mean number of VTEC surviving after exposure to 2 mg/ml caseicin A and B was reduced by 4.96 and 4.19 log(10) cfu/ml compared to the respective controls. The susceptibility of E. coli O157:H7 to the caseicin AMPs decreased as temperature, pH, water activity and inoculum size were reduced. The presence of sodium chloride (0.5-2.5%) did not affect the activity of caseicin A (p>0.05), however it did inhibit the activity of caseicin B. The presence of a competitive microflora cocktail did not significantly (p>0.05) affect the activities of the AMPs for the majority of the concentrations tested. Using a quantitative PCR assay, the levels of verotoxins (vt1 and vt2) expressed by E. coli O157:H7 following exposure to a sub-inhibitory concentration (0.5 mg/ml) of caseicin A showed that the verotoxin levels did not differ from the levels produced by the control cultures. The antimicrobial activity of caseicin A against E. coli O157:H7 was also tested in a model rumen system, however concentrations of ≥2 mg/ml did not significantly (p>0.05) reduce E. coli O157:H7 numbers in the model system over a 24 h period. The application of caseicin AMPs in food and/or animal production may be valuable in combination with other antimicrobials although further research is required. Copyright © 2011 Elsevier B.V. All rights reserved.

Storm Water Quality in Los Alamos Canyon following the Cerro Grande Fire

DOE Office of Scientific and Technical Information (OSTI.GOV)

M. Johansen; B. Enz; B. Gallaher

In May 2000, the Cerro Grande Fire burned about 7400 acres of forest on the Los Alamos National Laboratory (LANL) and about 10,000 acres in watersheds above LANL on Santa Fe National Forest lands. The resulting burned landscapes raised concerns of increased storm water runoff and transport of contaminants by runoff in the canyons traversing LANL. On June 2 and 3, 2000, rain fell in the Los Alamos Canyon watershed generating storm water runoff in the canyon bottom. This event was important in that it was the first significant runoff on LANL following the fire and occurred in a canyonmore » containing known legacy waste sites. Samples from this runoff were analyzed for radionuclide, metal, inorganic, and organic constituents. Results show radionuclide concentrations at or below previous (pre-fire) maximum levels at locations on LANL and downstream. However, greater concentrations of some fallout-associated radionuclides (cesium-137 and strontium-90) were seen arriving on LANL from upstream areas compared to pre-fire conditions. Tests indicate most of the radionuclides in the samples were bound to sediments, not dissolved in water. Most radionuclide concentrations in sediments were below LANL Screening Action Levels, with cesium-137 and strontium-90 as exceptions. Most radionuclide concentrations in samples taken at LANL's downstream boundary were greater than those taken upstream, indicating the presence of contributing sources on LANL. For comparison purposes, doses were calculated on a mrem per liter of unfiltered water basis for 11 radionuclides commonly associated with atmospheric fallout and with LANL operations. The maximum dose was 0.094 mrem per liter unfiltered water and was largely associated with plutonium-239/240. In contrast, all filtered samples had total doses less than 0.001 mrem per liter. Compared to past data, potential doses were not increased by the fire during this initial runoff event. Of the 25 metals tested for, seven were above pre-fire levels, including copper, lead, manganese, selenium, strontium, uranium, and zinc. However, dissolved metal concentrations did not exceed State livestock and wildlife standards. Of the 18 general chemistry parameters tested, eight exceeded historic norms, including calcium, potassium, total phosphorus, cyanide, and magnesium.« less

[A preliminary study on the autophagy level of human periodontal ligament cells regulated by nicotine].

PubMed

Yang, Du; Shuai, Yuan; Zhifei, Zhou; Lizheng, Wu; Lulu, Wang; Xing'an, Wu; Xiaojing, Wang

2017-04-01

To explore the effect of nicotine on the autophagy level of human periodontal ligament cells (hPDLCs). Periodontal tissues collected from premolars for orthodontic treatment reasons were used to culture hPDLCs. Western blot analysis was performed to test the most optimal time and concentration of nicotine on the autophagy level of the hPDLCs. Transmission electron microscope and immunofluorescence observation were carried out to detect the form of autophagosomes and expression of autophagy related protein LC3 in hPDLCs under this optimal condition. Protein expression of LC3Ⅱ was up regulated with the 12 h nicotine stimulating. Besides that, the up regulation of the protein expression of LC3Ⅱ was concentration dependent and nicotine with a concentration of 1×10⁻⁵ mol·L⁻¹ was the most optimal condition. Transmission electron microscope and immunofluorescence observations indicated that nicotine would activate the autophagy level of hPDLCs by increasing the number of autophagosomes and up regulating the expression of autophagy related protein LC3. Nicotine could increase autophagy level of hPDLCs, thus affecting the occurrence and development of smoking related periodontitis.

Effects of Petrol Exposure on Glucose, Liver and Muscle glycogen levels in the Common African toad Bufo regularis.

PubMed

Isehunwa, G O; Yusuf, I O; Alada, A Ar

2017-03-06

This study investigated the effects of exposure to petrol on blood glucose, liver and muscle glycogen levels in the common African toad Bufo regularis. A total of 126 adult toads of either sex weighing between 70-100g were used for this study. The experiment was divided into three phases. The phase 1 experiment the acute toxicity test consisted of animals divided into six groups of 10 toads per group and were exposed to water (H2O), H2O + Tween 80, 2ml/l, 3ml/l, 5ml/l, and 10ml/l of petrol respectively for 96 hours using the static renewal bioassay system. In the Phase 2 experiment, the animals were exposed to H2O, H2O + Tween 80, 0.14ml/l, 0.3ml/l, 0.6ml/l, and 1.13ml/l of petrol respectively for 3 days; while in phase 3 experiment they were exposed to petrol solutions for 14 days. After the various exposures, the blood glucose, liver and muscle glycogen contents were determined using standard methods. The results of the study showed that the median lethal concentration of petrol (96 hours LC50) was 4.5ml/l and sub-lethal concentration of petrol caused mortality of animals. Exposure to petrol solutions for 3 days had no significant effect on blood glucose level of the animals but caused significant decrease in the liver and muscle glycogen levels at high concentrations. In the animals exposed to petrol solutions for 14 days, there was a significant increase in glucose levels and significant reduction in liver and muscle glycogen levels at high concentrations when compared with the control. The results show that sub-lethal concentrations of petrol can cause mortality of animals, hyperglycemia and reduction in liver and muscle glycogen levels. The effects of petrol exposure on carbohydrate metabolism depend on the concentration and duration of exposure.

Vehicle occupant exposure to carbon monoxide.

PubMed

Koushki, P A; al-Dhowalia, K H; Niaizi, S A

1992-12-01

This paper focuses on the auto commuting micro-environment and presents typical carbon monoxide (CO) concentrations to which auto commuters in central Riyadh, Saudi Arabia were exposed. Two test vehicles traveling over four main arterial roadways were monitored for inside and outside CO levels during eighty peak and off-peak hours extending over an eight-month period. The relative importance of several variables which explained the variability in CO concentrations inside autos was also assessed. It was found that during peak hours auto commuters were exposed to mean CO levels that ranged from 30 to 40 ppm over trips that typically took between 25 to 40 minutes. The mean ratio of inside to outside CO levels was 0.84. Results of variance component analyses indicated that the most important variables affecting CO concentrations inside autos were, in addition to the smoking of vehicle occupants, traffic volume, vehicle speed, period of day and wind velocity. An increase in traffic volume from 1,000 to 5,000 vehicles per hour (vph) increased mean CO level exposure by 71 percent. An increase in vehicle speed from 14 to 55 km/h reduced mean CO exposure by 36 percent. The number of traffic interruptions had a moderate effect on mean concentrations of CO inside vehicles.

Comparative toxicities of selected rare earth elements: Sea urchin embryogenesis and fertilization damage with redox and cytogenetic effects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pagano, Giovanni, E-mail: gbpagano@tin.it; Guida, Marco; Siciliano, Antonietta

Background: Broad-ranging adverse effects are known for rare earth elements (REE), yet only a few studies tested the toxicity of several REE, prompting studies focusing on multi-parameter REE toxicity. Methods: Trichloride salts of Y, La, Ce, Nd, Sm, Eu and Gd were tested in Paracentrotus lividus sea urchin embryos and sperm for: (1) developmental defects in either REE-exposed larvae or in the offspring of REE-exposed sperm; (2) fertilization success; (3) mitotic anomalies in REE-exposed embryos and in the offspring of REE-exposed sperm, and (4) reactive oxygen species (ROS) formation, and malondialdehyde (MDA) and nitric oxide (NO) levels. Results: REEs affectedmore » P. lividus larvae with concentration-related increase in developmental defects, 10{sup −6} to 10{sup −4} M, ranking as: Gd(III)>Y(III)>La(III)>Nd(III)≅Eu(III)>Ce(III)≅Sm(III). Nominal concentrations of REE salts were confirmed by inductively coupled plasma mass spectrometry (ICP-MS). Significant increases in MDA levels, ROS formation, and NO levels were found in REE-exposed embryos. Sperm exposure to REEs (10{sup −5} to 10{sup −4} M) resulted in concentration-related decrease in fertilization success along with increase in offspring damage. Decreased mitotic activity and increased aberration rates were detected in REE-exposed embryos and in the offspring of REE-exposed sperm. Conclusion: REE-associated toxicity affecting embryogenesis, fertilization, cytogenetic and redox endpoints showed different activities of tested REEs. Damage to early life stages, along with redox and cytogenetic anomalies should be the focus of future REE toxicity studies. - Highlights: • Seven rare earth elements exerted different effects on sea urchin early life stages. • Embryo-, spermio- and mitotoxicity, and oxidative/ nitrosative stress were found. • Nominal vs. analytical REE concentrations were checked. • Comparative toxicities were evaluated for the different REE.« less

Prenatal stress decreases glycogen synthase kinase-3 phosphorylation in the rat frontal cortex.

PubMed

Szymańska, Magdalena; Suska, Anna; Budziszewska, Bogusława; Jaworska-Feil, Lucylla; Basta-Kaim, Agnieszka; Leśkiewicz, Monika; Kubera, Marta; Gergont, Aleksandra; Kroczka, Sławomir; Kaciński, Marek; Lasoń, Władysław

2009-01-01

It has been postulated that hyperactive glycogen synthase kinase-3 (GSK-3) is an important factor in the pathogenesis of depression, and that this enzyme also contributes to the mechanism of antidepressant drug action. In the present study, we investigated the effect of prenatal stress (an animal model of depression) and long-term treatment with antidepressant drugs on the concentration of GSK-3beta and its main regulating protein kinase B (PKB, Akt). The concentration of GSK-3beta, its inactive form (phospho-Ser9-GSK-3beta), and the amounts of active (phospho-Akt) and total Akt were determined in the hippocampus and frontal cortex in rats. In order to verify our animal model of depression, immobility time in the forced swim test (Porsolt test) was also determined.We found that prenatally stressed rats display a high level of immobility in the Porsolt test and chronic treatment with imipramine, fluoxetine, mirtazapine and tianeptine normalize this change. Western blot analysis demonstrated that GSK-3beta levels were significantly elevated in the frontal cortex, but not in the hippocampus, of prenatally stressed rats. The concentration of its non-active form (phospho-Ser9-GSK-3beta) was decreased only in the former brain structure. No changes were found in the amounts of active (phospho-Akt) and total Akt in both studied brain structures. Chronic treatment with antidepressant drugs diminished stress-induced alterations in GSK-3beta and phospho-GSK-3beta the frontal cortex, but had no effect on the concentration of these enzymes in the hippocampus. Moreover, levels of Akt and phospho-Akt in all experimental groups remained unchanged. Since our animal model of depression is connected with hyperactivity of the HPA axis, our results suggest that GSK-3beta is an important intracellular target for maladaptive glucocorticoid action on frontal cortex neurons and in antidepressant drug effects. Furthermore, the influence of stress and antidepressant drugs on GSK-3beta does not appear to impact the kinase activity of Akt.

USE OF NATIVE PLANTS FOR REMEDIATION OF TRICHLOROETHYLENE: I. DECIDUOUS TREES.

PubMed

Strycharz, S; Newman, L

2009-02-01

Phytoremediation of trichloroethylene (TCE) can be accomplished using fast-growing, deep-rooting trees. The most commonly used tree for phytoremediation of TCE has been the hybrid poplar. This study looks at native southeastern trees of the United States as alternatives to the use of hybrid poplar. The use of native trees for phytoremediation allows for simultaneous restoration of contaminated sites. A 2-mo, greenhouse-based study was conducted to determine if sycamore (Plantanus L.), eastern cottonwood (Populus deltoides), sweetgum (Liquidambar styraciflua L.), and willow (Salix sachalinensis) trees possess the ability to degrade TCE by assessing TCE metabolite formation in the plant tissue. In addition to the metabolic capabilities of each tree species, growth parameters were measured including change in height, water usage, total fresh weight of each tissue type, and calculated total leaf surface area. Willow trees had the greatest increase in height among all trees tested; however, at higher concentrations TCE inhibits growth. Sycamore trees had the highest overall leaf surface area and total biomass, which correlated with sycamore trees also having the highest average water usage over the course of the experiment. Carbon tubes used to sample transpiration gases from sycamore, sweetgum, and cottonwood trees did not contain detectable levels of TCE. Tenex sample collection tubes used to sample willow trees during TCE exposure showed average TCE concentrations of up to 0.354 ng TCE cm -2 leaf tissue. All exposed trees contained TCE in the root, stem, and leaf tissues. The concentration of TCE remaining in tissues at the conclusion of the experiment varied, with the highest levels found in the roots and the lowest levels found in the leaves. Metabolites were also observed in different tissue types of all trees tested. The highest concentrations of trichloroacetic acid were observed in the leaves of the sycamore trees and cottonwood trees. Based on the growth parameters tested and the ability to metabolize TCE, sycamore and native cottonwood species are the best candidates for phytoremediation from this study.

Effects of locust bean gum and mono- and diglyceride concentrations on particle size and melting rates of ice cream.

PubMed

Cropper, S L; Kocaoglu-Vurma, N A; Tharp, B W; Harper, W J

2013-06-01

The objective of this study was to determine how varying concentrations of the stabilizer, locust bean gum (LBG), and different levels of the emulsifier, mono- and diglycerides (MDGs), influenced fat aggregation and melting characteristics of ice cream. Ice creams were made containing MDGs and LBG singly and in combination at concentrations ranging between 0.0% to 0.14% and 0.0% to 0.23%, respectively. Particle size analysis, conducted on both the mixes and ice cream, and melting rate testing on the ice cream were used to determine fat aggregation. No significant differences (P < 0.05) were found between particle size values for experimental ice cream mixes. However, higher concentrations of both LBG and MDG in the ice creams resulted in values that were larger than the control. This study also found an increase in the particle size values when MDG levels were held constant and LBG amounts were increased in the ice cream. Ice creams with higher concentrations of MDG and LBG together had the greatest difference in the rate of melting than the control. The melting rate decreased with increasing LBG concentrations at constant MDG levels. These results illustrated that fat aggregation may not only be affected by emulsifiers, but that stabilizers may play a role in contributing to the destabilization of fat globules. © 2013 Institute of Food Technologists®

Comparative aquatic toxicity of the pyrethroid insecticide lambda-cyhalothrin and its resolved isomer gamma-cyhalothrin.

PubMed

Giddings, Jeffrey M; Barber, Ian; Warren-Hicks, William

2009-02-01

In this review we compare the sensitivity of a range of aquatic invertebrate and fish species to gamma-cyhalothrin (GCH), the insecticidally active enantiomer of the synthetic pyrethroid lambda-cyhalothrin (LCH), in single-species laboratory tests and outdoor multi-species ecosystem tests. Species sensitivity distribution curves for GCH gave median HC(5) values of 0.47 ng/L for invertebrates, and 23.7 ng/L for fish, while curves for LCH gave median HC(5) values of 1.05 ng/L and 40.9 ng/L for invertebrates and fish, respectively. A model ecosystem test with GCH gave a community-level no observed effect concentration (NOEC(community)) of 5 ng/L, while model ecosystem tests with LCH gave a NOEC(community) of 10 ng/L. These comparisons between GCH and LCH indicate that the single active enantiomer causes effects at approximately one-half the concentration at which the racemate causes similar effects.

Inhibitory effects of selected Turkish spices and oregano components on some foodborne fungi.

PubMed

Akgül, A; Kivanç, M

1988-05-01

The inhibitory effects of 10 selected Turkish spices, oregano essential oil, thymol and carvacrol towards growth of 9 foodborne fungi were investigated in culture media with pH 3.5 and 5.5. The antifungal effects of sodium chloride, sorbic acid and sodium benzoate and the combined use of oregano with sodium chloride were also tested under the same conditions for comparison. Of the spices tested, only sodium chloride were also tested under the same conditions for comparison. Of the spices tested, only oregano at 1.0, 1.5, 2.0% (w/v) levels showed effect on all fungi. 8% (w/v) sodium chloride was less effective than oregano. Oregano essential oil, thymol or carvacrol at concentrations of 0.025% and 0.05% completely inhibited the growth of all fungi, showing greater inhibition than sorbic acid at the same concentrations. The combined use of oregano and sodium chloride exhibited a synergistic antifungal effect.

Monitoring and assessment of mercury pollution in the vicinity of a chloralkali plant. III. Concentration and genotoxicity of mercury in the industrial effluent and contaminated water of Rushikulya estuary, India.

PubMed

Panda, K K; Lenka, M; Panda, B B

1992-01-01

Aquatic mercury pollution of the Rushikulya estuary in the vicinity of the chloralkali plant at Ganjam, India was monitored over a period from October 1987 to May 1989. The concentrations of aquatic mercury in the water samples taken from the effluent channel and from different sites along the course of the estuary covering a distance of 2 km were periodically recorded and ranged from 0 to 0.5 mg/l. The bioconcentration and genotoxicity of aquatic mercury in the samples were assessed by the Allium micronucleus (MNC) assay. The frequency of cells with MNC was highly correlated not only with bioconcentrated mercury (root mercury) but also with the levels of aquatic mercury. The threshold assessment values such as effective concentration fifty (EC50) for root growth, lowest effective concentration tested (LECT), and highest ineffective concentration tested (HICT) for induction of MNC in Allium MNC assay for the present aquatic industrial mercury were determined to be 0.14, 0.06 and 0.02 mg/l, respectively.

The Influence of Different Representations on Solving Concentration Problems at Elementary School

NASA Astrophysics Data System (ADS)

Liu, Chia-Ju; Shen, Ming-Hsun

2011-10-01

This study investigated the students' learning process of the concept of concentration at the elementary school level in Taiwan. The influence of different representational types on the process of proportional reasoning was also explored. The participants included nineteen third-grade and eighteen fifth-grade students. Eye-tracking technology was used in conducting the experiment. The materials were adapted from Noelting's (1980a) "orange juice test" experiment. All problems on concentration included three stages (the intuitive, the concrete operational, and the formal operational), and each problem was displayed in iconic and symbolic representations. The data were collected through eye-tracking technology and post-test interviews. The results showed that the representational types influenced students' solving of concentration problems. Furthermore, the data on eye movement indicated that students used different strategies or rules to solve concentration problems at the different stages of the problems with different representational types. This study is intended to contribute to the understanding of elementary school students' problem-solving strategies and the usability of eye-tracking technology in related studies.

The effect of feed supplementation with effective microorganisms (EM) on pro- and anti-inflammatory cytokine concentrations in pigs.

PubMed

Laskowska, Ewa; Jarosz, Łukasz; Grądzki, Zbigniew

2017-12-01

Effective microorganisms (EM) are used in numerous fields associated with agriculture. The beneficial effects of EM on the general health of pigs and on production parameters are also determined by the influence of these microbes on immunity. The aim of the study was to assess the effect of feed supplementation with EM on the concentration of pro- and anti-inflammatory cytokines in the serum and in a culture of PBMCs with and without ConA stimulation in pigs. ELISA kits were used to determine the cytokine levels in the porcine serum and the PBMC culture supernatants. Evaluation of the serum concentration of cytokines revealed statistically significantly higher concentrations of IL-2, IL-4, IL-10, IFN-γ and TNF-α in the pigs receiving EM Bokashi. The highest concentration of TGF-β in the experimental group was noted on the final test day. Evaluation of cytokine concentrations in the PBMC cultures revealed statistically significantly higher concentrations of IL-2, IL-4 and IL-10 from the third day of the experiment. Statistically significantly higher concentrations of TNF-α were obtained in the unstimulated PBMC culture on the second test day and in the culture treated with ConA on the second and the third test days. The results of our study indicate that supplementation of pig feed with EM Bokashi activates the cell-mediated and humoral immune response, ensuring that Th1/Th2 balance is maintained and enhancing immune processes protecting the body against infection. Copyright © 2017. Published by Elsevier Ltd.

Preliminary risk assessment of the lipid-regulating pharmaceutical clofibric acid, for three estuarine species.

PubMed

Emblidge, J P; Delorenzo, M E

2006-02-01

Clofibric acid is the active metabolite of several fibrate drugs prescribed to reduce blood cholesterol levels. It is persistent and widely detected in the environment. Clofibric acid toxicity was assessed using three estuarine organisms: an alga (Dunaliella tertiolecta), a crustacean (Palaemonetes pugio), and a fish (Fundulus heteroclitus). Mortality and sublethal physiological responses (protein, lipid, cholesterol, and cytochrome P450 levels) were examined. Clofibric acid did not significantly affect cell density or growth rate of D. tertiolecta (concentrations 1000 microg/L). Survival of P. pugio and F. heteroclitus were also unaffected at clofibric acid concentrations 1000 microg/L. In addition, no significant changes in the sublethal test endpoints were found. An additional chronic (17-day) exposure of F. heteroclitus to clofibric acid (10 microg/L) was conducted and found no effects on survival or sublethal endpoints. The rabbit polyclonal CYP450 4A antibody did cross react with F. heteroclitus, demonstrating that a CYP4A-like isoform is present in this teleost species and may be used in future induction studies. Clofibric acid, however, did not alter CYP4A levels in F. heteroclitus. Measured concentrations in the environment have not exceeded 10 microg/L. Therefore, the results of this study indicate a low risk of adverse effects from environmental exposure to clofibric acid for the species tested.

Persistent organic contaminants and steroid hormones levels in Morelet's crocodiles from the Southern Gulf of Mexico.

PubMed

Gonzalez-Jauregui, Mauricio; Valdespino, Carolina; Salame-Méndez, Arturo; Aguirre-León, Gustavo; Rendón-Vonosten, Jaime

2012-04-01

Effects of endocrine disruptors on reproductive variables of top predators, such as alligators and crocodiles, have long been cited. Due to their long life span, these predators provide us with historic contaminant annals. In this study we tried to test whether lifestyle (free-ranging vs. farm animals) and reproductive age of Morelet's crocodiles in Campeche, Mexico, affect the bioaccumulation of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). Subsequently, we tested to see whether their concentration was related to steroid hormones (testosterone and estradiol-17β) levels once normal cyclic hormone variation and reproductive age had been taken into account. From the group of contaminants considered (analyzed as families), only frequency of hexachlorocyclohexanes (∑HCH) and ∑PCB permitted analyses. Whereas there was a greater concentration of ∑HCH bioaccumulated by free-ranging crocodiles, ∑PCB was found in equal quantities in free-ranging and farm animals. No difference was observed in relation to reproductive age for any of the contaminants. However, ∑PCB concentrations were related to testosterone levels among female crocodiles. This androgenic effect of ∑PCB has not been reported previously. Because testosterone promotes aggressive behavior in vertebrates, excessive aggression during the estrous season, or when female crocodiles should be caring for their young, could result in reproductive failure in Morelet's crocodiles and potential long-term decline of the population.

[Influence of phthalates from Shaying river on children's intelligence and secretion of thyroid hormone].

PubMed

Li, Anqi; Tang, Chunyu; Hang, Hui; Cheng, Xuemin; Gao, Yalin; Cheng, Hongyang; Huang, Qi; Luo, Yixin; Xue, Yutang; Zuo, Qiting; Ba, Yue; Cui, Liuxin

2013-03-01

To investigate the effect of phthalates exposure from drinking water on children's intelligence and secretion of thyroid hormone. Two villages in S County were selected randomly as polluted area and control area according to the distance from the Shaying river basin. Phthalates including DEP, DBP, DMP, DEHP were measured both in the river water and drinking water using HPLC method. Children aged 8 to 13 years old studying in the village primary school were recruited by cluster sampling (n = 154). The combined Reven Test was used to test children intelligence and ELISA method was used to determined thyroid hormone levels. The concentrations of phthalates (DEP, DBP) were exceeding standards of surface water quality in any of the three sections of the river. Compared to the control area, the concentration of DEP and DBP in drinking water were significant higher in the polluted area than that in control area (P < 0.05). Children from polluted area had significant higher FT4 concentration compared to children from control area (P < 0.05). Intelligence level in children from polluted area was lower than that from control area (P < 0.05). The drinking water has been polluted by Shaying river and thyroid hormones levels of children were affected in the polluted areas. It is necessary to verify if this change is related to the phthalates.

Questionable Specificity of Genetic Total Faecal Pollution Markers for Integrated Water Quality Monitoring and Source Tracking

NASA Astrophysics Data System (ADS)

Vierheilig, Julia; Reischer, Georg H.; Farnleitner, Andreas H.

2010-05-01

Characterisation of microbial faecal hazards in water is a fundamental aspect for target-orientated water resources management to achieve appropriate water quality for various purposes like water supply or agriculture and thus to minimize related health risks. Nowadays the management of water resources increasingly demands detailed knowledge on the extent and the origin of microbial pollution. Cultivation of standard faecal indicator bacteria, which has been used for over a century to test the microbiological water quality, cannot sufficiently meet these challenges. The abundant intestinal bacterial populations are very promising alternative targets for modern faecal indication systems. Numerous assays for the detection of genetic markers targeting source-specific populations of the phylum Bacteroidetes have been developed in recent years. In some cases markers for total faecal pollution were also proposed in order to relate source-specific marker concentrations to general faecal pollution levels. However, microbial populations in intestinal and non-intestinal systems exhibit a dazzling array of diversity and molecular analysis of microbial faecal pollution has been based on a fragmentary puzzle of very limited sequence information. The aim of this study was to test the available qPCR-based methods detecting genetic Bacteroidetes markers for total faecal pollution in terms of their value and specificity as indicators of faecal pollution. We applied the AllBac (Layton et al., 2006) the BacUni (Kildare et al., 2007) and the Bacteroidetes (Dick and Field, 2004) assays on soil DNA samples. Samples were collected in well characterised karst spring catchments in Austria's Eastern Calcareous Alps. They were at various levels of altitude between 800 and 1800 meters above sea level and from several different habitats (woodland, alpine pastures, krummholz). In addition we tried to choose sampling sites representing a presumptive gradient of faecal pollution levels. For example sites with obvious faecal influence (e.g. right next to a cowpat) were included as well as more pristine sites without faecal influence from large animals (e.g. fenced areas). Surprisingly, results from investigations with the AllBac assay showed concentrations of the total faecal marker in soil in the range of 106 to 109 Marker Equivalents per g of soil, which is equal or only slightly lower than the concentrations of this particular marker in faeces or raw sewage. Preliminary results from the other tested assays seem to confirm that the targeted markers are also highly abundant in soils. In addition, the markers were present in comparable concentrations in soils from pristine locations as well as in soils under the potential influence of faeces giving a strong indication that these methods also target non-intestinal, autochthonous soil populations. In contrast, source-specific markers (ruminant-specific BacR and human-specific BacH, Reischer et al., 2007, 2006) could only be detected in 30 to 50% of the soil samples at concentrations close to the detection limit, which is at least four orders of magnitude lower than in faecal samples of the respective target sources, ruminant animals and humans. The achieved results call the applicability of the proposed qPCR-based assays for total faecal pollution into question. In fact the assays do not seem to be specific for intestinal Bacteroidetes populations at all and the respective marker concentration levels in pristine soils negate their applicability in the investigated areas. This study also emphasizes the need to test the specificity and sensitivity of qPCR-based assays for total faecal pollution on the local level and especially against non-intestinal environmental samples, which might contribute to marker levels in the aquatic compartment. In conclusion there is a strong demand for marker-based detection techniques for total faecal pollution in water quality monitoring and risk assessment but currently none of the tested assays seems to meet the methodical requirements.

MTBE; to what extent will past releases contaminate community water supply wells?(Brief Article)

USGS Publications Warehouse

Johnson, Richard; Pankow, James; Bender, David A.; Price, Curtis; Zogorski, John S.

2000-01-01

The increasing frequency of detection of the widely used gasoline additive methyl tertbutyl ether (MTBE) in both ground- and surface waters is receiving much attention from the media, environmental scientists, state environmental agencies, and federal agencies. At the national level, the September 15,1999, Report of the Blue Ribbon Panel on Oxygenates in Gasoline (i) )tates that between 5 and 10% of community drinking water supplies in high MTBE use areas show at least detectable concentrations of MTBE, and about 1% of those systems are characterized by levels of this compound that are above 20 pg/L. In Maine, a desire to determine the extent of MTBE contamination led to a 1998 study (2) that revealed that this compound is found at levels above 0.1 pg/L in 16% of 951 randomly selected household wells and in 16% of the 793 community water systems tested in that state (37 wells were not tested). The study also suggested that between 1400 and 5200 household wells may have levels above 35 pg/L, although no community water supplies were found to be above that concentration. For comparison, Maryland, New Hampshire, New York, and California have set MTBE remediation "action levels" at or below 20 pg/L, and EPA has set its advisory level for taste and odor at 20-40 pg/L (3).

Fungicidal values of bio-oils and their lignin-rich fractions obtained from wood/bark fast pyrolysis.

PubMed

Mohan, Dinesh; Shi, Jenny; Nicholas, Darrel D; Pittman, Charles U; Steele, Philip H; Cooper, Jerome E

2008-03-01

Pine wood, pine bark, oak wood and oak bark were pyrolyzed in an auger reactor. A total of 16 bio-oils or pyrolytic oils were generated at different temperatures and residence times. Two additional pine bio-oils were produced at the National Renewable Energy Laboratory in a fluidized-bed reactor at different temperatures. All these bio-oils were fractionated to obtain lignin-rich fractions which consist mainly of phenols and neutrals. The pyrolytic lignin-rich fractions were obtained by liquid-liquid extraction. Whole bio-oils and their lignin-rich fractions were studied as potential environmentally benign wood preservatives to replace metal-based CCA and copper systems that have raised environmental concerns. Each bio-oil and several lignin-rich fractions were tested for antifungal properties. Soil block tests were conducted using one brown-rot fungus (Gloeophyllum trabeum) and one white-rot fungus (Trametes versicolor). The lignin-rich fractions showed greater fungal inhibition than whole bio-oils for a impregnation solution 10% concentration level. Water repellence tests were also performed to study wood wafer swelling behavior before and after bio-oil and lignin-rich fraction treatments. In this case, bio-oil fractions did not exhibit higher water repellency than whole bio-oils. Comparison of raw bio-oils in soil block tests, with unleached wafers, at 10% and 25% bio-oil impregnation solution concentration levels showed excellent wood preservation properties at the 25% level. The good performance of raw bio-oils at higher loading levels suggests that fractionation to generate lignin-rich fractions is unnecessary. At this more effective 25% loading level in general, the raw bio-oils performed similarly. Prevention of leaching is critically important for both raw bio-oils and their fractions to provide decay resistance. Initial tests of a polymerization chemical to prevent leaching showed some success.

Effect of censoring trace-level water-quality data on trend-detection capability

USGS Publications Warehouse

Gilliom, R.J.; Hirsch, R.M.; Gilroy, E.J.

1984-01-01

Monte Carlo experiments were used to evaluate whether trace-level water-quality data that are routinely censored (not reported) contain valuable information for trend detection. Measurements are commonly censored if they fall below a level associated with some minimum acceptable level of reliability (detection limit). Trace-level organic data were simulated with best- and worst-case estimates of measurement uncertainty, various concentrations and degrees of linear trend, and different censoring rules. The resulting classes of data were subjected to a nonparametric statistical test for trend. For all classes of data evaluated, trends were most effectively detected in uncensored data as compared to censored data even when the data censored were highly unreliable. Thus, censoring data at any concentration level may eliminate valuable information. Whether or not valuable information for trend analysis is, in fact, eliminated by censoring of actual rather than simulated data depends on whether the analytical process is in statistical control and bias is predictable for a particular type of chemical analyses.

Isometric quadriceps strength determines sailing performance and neuromuscular fatigue during an upwind sailing emulation.

PubMed

Bourgois, Jan G; Callewaert, Margot; Celie, Bert; De Clercq, Dirk; Boone, Jan

2016-01-01

This study investigates the physiological responses to upwind sailing on a laser emulation ergometer and analyses the components of the physical profile that determine the physiological responses related to sailing level. Ten male high-level laser sailors performed an upwind sailing test, incremental cycling test and quadriceps strength test. During the upwind sailing test, heart rate (HR), oxygen uptake, ventilation, respiratory exchange ratio, rating of perceived exertion (RPE) and lactate concentration were measured, combined with near-infrared spectroscopy (NIRS) and electromyography (EMG) registration of the M. Vastus lateralis. Repeated measures ANOVA showed for the cardio-respiratory, metabolic and muscles responses (mean power frequency [MPF], root mean square [RMS], deoxy[Hb+Mb]) during the upwind sailing test an initial significant increase followed by a stabilisation, despite a constant increase in RPE. Stepwise regression analysis showed that better sailing level was for 46.5% predicted by lower MPF decrease. Lower MPF decrease was for 57.8% predicted by a higher maximal isometric quadriceps strength. In conclusion, this study indicates that higher sailing level was mainly determined by a lower rate of neuromuscular fatigue during the upwind sailing test (as indicated by MPF decrease). Additionally, the level of neuromuscular fatigue was mainly determined by higher maximal isometric quadriceps strength stressing the importance of resistance training in the planning of training.

Mixtures of Chemical Pollutants at European Legislation Safety Concentrations: How Safe Are They?

PubMed Central

Carvalho, Raquel N.; Arukwe, Augustine; Ait-Aissa, Selim; Bado-Nilles, Anne; Balzamo, Stefania; Baun, Anders; Belkin, Shimshon; Blaha, Ludek; Brion, François; Conti, Daniela; Creusot, Nicolas; Essig, Yona; Ferrero, Valentina E. V.; Flander-Putrle, Vesna; Fürhacker, Maria; Grillari-Voglauer, Regina; Hogstrand, Christer; Jonáš, Adam; Kharlyngdoh, Joubert B.; Loos, Robert; Lundebye, Anne-Katrine; Modig, Carina; Olsson, Per-Erik; Pillai, Smitha; Polak, Natasa; Potalivo, Monica; Sanchez, Wilfried; Schifferli, Andrea; Schirmer, Kristin; Sforzini, Susanna; Stürzenbaum, Stephen R.; Søfteland, Liv; Turk, Valentina; Viarengo, Aldo; Werner, Inge; Yagur-Kroll, Sharon; Zounková, Radka; Lettieri, Teresa

2014-01-01

The risk posed by complex chemical mixtures in the environment to wildlife and humans is increasingly debated, but has been rarely tested under environmentally relevant scenarios. To address this issue, two mixtures of 14 or 19 substances of concern (pesticides, pharmaceuticals, heavy metals, polyaromatic hydrocarbons, a surfactant, and a plasticizer), each present at its safety limit concentration imposed by the European legislation, were prepared and tested for their toxic effects. The effects of the mixtures were assessed in 35 bioassays, based on 11 organisms representing different trophic levels. A consortium of 16 laboratories was involved in performing the bioassays. The mixtures elicited quantifiable toxic effects on some of the test systems employed, including i) changes in marine microbial composition, ii) microalgae toxicity, iii) immobilization in the crustacean Daphnia magna, iv) fish embryo toxicity, v) impaired frog embryo development, and vi) increased expression on oxidative stress-linked reporter genes. Estrogenic activity close to regulatory safety limit concentrations was uncovered by receptor-binding assays. The results highlight the need of precautionary actions on the assessment of chemical mixtures even in cases where individual toxicants are present at seemingly harmless concentrations. PMID:24958932

Comparison of dialysis membrane diffusion samplers and two purging methods in bedrock wells

USGS Publications Warehouse

Imbrigiotta, T.E.; Ehlke, T.A.; Lacombe, P.J.; Dale, J.M.; ,

2002-01-01

Collection of ground-water samples from bedrock wells using low-flow purging techniques is problematic because of the random spacing, variable hydraulic conductivity, and variable contamination of contributing fractures in each well's open interval. To test alternatives to this purging method, a field comparison of three ground-water-sampling techniques was conducted on wells in fractured bedrock at a site contaminated primarily with volatile organic compounds. Constituent concentrations in samples collected with a diffusion sampler constructed from dialysis membrane material were compared to those in samples collected from the same wells with a standard low-flow purging technique and a hybrid (high-flow/low-flow) purging technique. Concentrations of trichloroethene, cis-1,2-dichloroethene, vinyl chloride, calcium, chloride, and alkalinity agreed well among samples collected with all three techniques in 9 of the 10 wells tested. Iron concentrations varied more than those of the other parameters, but their pattern of variation was not consistent. Overall, the results of nonparametric analysis of variance testing on the nine wells sampled twice showed no statistically significant difference at the 95-percent confidence level among the concentrations of volatile organic compounds or inorganic constituents recovered by use of any of the three sampling techniques.

Optoacoustic 13C-breath test analyzer

NASA Astrophysics Data System (ADS)

Harde, Hermann; Helmrich, Günther; Wolff, Marcus

2010-02-01

The composition and concentration of exhaled volatile gases reflects the physical ability of a patient. Therefore, a breath analysis allows to recognize an infectious disease in an organ or even to identify a tumor. One of the most prominent breath tests is the 13C-urea-breath test, applied to ascertain the presence of the bacterium helicobacter pylori in the stomach wall as an indication of a gastric ulcer. In this contribution we present a new optical analyzer that employs a compact and simple set-up based on photoacoustic spectroscopy. It consists of two identical photoacoustic cells containing two breath samples, one taken before and one after capturing an isotope-marked substrate, where the most common isotope 12C is replaced to a large extent by 13C. The analyzer measures simultaneously the relative CO2 isotopologue concentrations in both samples by exciting the molecules on specially selected absorption lines with a semiconductor laser operating at a wavelength of 2.744 μm. For a reliable diagnosis changes of the 13CO2 concentration of 1% in the exhaled breath have to be detected at a concentration level of this isotope in the breath of about 500 ppm.

Acceptance of sugar reduction in flavored yogurt.

PubMed

Chollet, M; Gille, D; Schmid, A; Walther, B; Piccinali, P

2013-09-01

To investigate what level of sugar reduction is accepted in flavored yogurt, we conducted a hedonic test focusing on the degree of liking of the products and on optimal sweetness and aroma levels. For both flavorings (strawberry and coffee), consumers preferred yogurt containing 10% added sugar. However, yogurt containing 7% added sugar was also acceptable. On the just-about-right scale, yogurt containing 10% sugar was more often described as too sweet compared with yogurt containing 7% sugar. On the other hand, the sweetness and aroma intensity for yogurt containing 5% sugar was judged as too low. A second test was conducted to determine the effect of flavoring concentration on the acceptance of yogurt containing 7% sugar. Yogurts containing the highest concentrations of flavoring (11% strawberry, 0.75% coffee) were less appreciated. Additionally, the largest percentage of consumers perceived these yogurts as "not sweet enough." These results indicate that consumers would accept flavored yogurts with 7% added sugar instead of 10%, but 5% sugar would be too low. Additionally, an increase in flavor concentration is undesirable for yogurt containing 7% added sugar. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

In situ treatment with activated carbon reduces bioaccumulation in aquatic food chains.

PubMed

Kupryianchyk, D; Rakowska, M I; Roessink, I; Reichman, E P; Grotenhuis, J T C; Koelmans, A A

2013-05-07

In situ activated carbon (AC) amendment is a new direction in contaminated sediment management, yet its effectiveness and safety have never been tested on the level of entire food chains including fish. Here we tested the effects of three different AC treatments on hydrophobic organic chemical (HOC) concentrations in pore water, benthic invertebrates, zooplankton, and fish (Leuciscus idus melanotus). AC treatments were mixing with powdered AC (PAC), mixing with granular AC (GAC), and addition-removal of GAC (sediment stripping). The AC treatments resulted in a significant decrease in HOC concentrations in pore water, benthic invertebrates, zooplankton, macrophytes, and fish. In 6 months, PAC treatment caused a reduction of accumulation of polychlorobiphenyls (PCB) in fish by a factor of 20, bringing pollutant levels below toxic thresholds. All AC treatments supported growth of fish, but growth was inhibited in the PAC treatment, which was likely explained by reduced nutrient concentrations, resulting in lower zooplankton (i.e., food) densities for the fish. PAC treatment may be advised for sites where immediate ecosystem protection is required. GAC treatment may be equally effective in the longer term and may be adequate for vulnerable ecosystems where longer-term protection suffices.

Postprandial Levels of Branch Chained and Aromatic Amino Acids Associate with Fasting Glycaemia.

PubMed

Ottosson, Filip; Ericson, Ulrika; Almgren, Peter; Nilsson, Jeanette; Magnusson, Martin; Fernandez, Céline; Melander, Olle

2016-01-01

High fasting plasma concentrations of isoleucine, phenylalanine, and tyrosine have been associated with increased risk of hyperglycaemia and incidence of type 2 diabetes. Whether these associations are diet or metabolism driven is unknown. We examined how the dietary protein source affects the postprandial circulating profile of these three diabetes associated amino acids (DMAAs) and tested whether the postprandial DMAA profiles are associated with fasting glycaemia. We used a crossover design with twenty-one healthy individuals and four different isocaloric test meals, containing proteins from different dietary sources (dairy, fish, meat, and plants). Analysis of the postprandial DMAAs concentrations was performed using targeted mass spectrometry. A DMAA score was defined as the sum of all the three amino acid concentrations. The postprandial area under the curve (AUC) of all the three amino acids and the DMAA score was significantly greater after intake of the meal with dairy protein compared to intake of the three other meals. The postprandial AUC for the DMAA score and all the three amino acids strongly associated with fasting glucose level and insulin resistance. This indicates the importance of the postprandial kinetics and metabolism of DMAAs in understanding the overall association between DMAAs and glycaemia.

Evaluation of lower leg function in patients with Achilles tendinopathy.

PubMed

Silbernagel, Karin Grävare; Gustavsson, Alexander; Thomeé, Roland; Karlsson, Jon

2006-11-01

Achilles tendinopathy is considered to be one of the most common overuse injuries in elite and recreational athletes. However, the effect that the Achilles tendinopathy has on patients' physical performance is still unclear. The purpose of this study was to evaluate if Achilles tendinopathy caused functional deficits on the injured side compared with the non-injured side in patients. A test battery comprised of tests for different aspects of muscle-tendon function of the gastrocnemius, soleus and Achilles tendon complex was developed to evaluate lower leg function. The test battery's test-retest reliability and sensitivity (the percent probability that the tests would demonstrate abnormal lower limb symmetry index in patients) were also evaluated. The test battery consisted of three jump tests, a counter movements jump (CMJ), a drop counter movement jump (drop CMJ) and hopping, and two strength tests, concentric toe-raises, eccentric-concentric toe-raises and toe-raises for endurance. The reliability was evaluated through a test-retest design on 15 healthy subjects. The test battery's sensitivity and possible functional deficits in patients with Achilles tendinopathy were evaluated on 42 patients (19 women and 23 men). An excellent reliability was found between test days 1-2 and 2-3 for all tests (ICC = 0.76-0.94) except for concentric toe-raise, test 2-3, which had fair reliability (ICC = 0.73). The methodological error ranged from 8 to 17%. There were significant differences (P = 0.001-0.049) between the non-injured (or least symptomatic) side and injured (most symptomatic) side for hopping, drop CMJ, concentric and eccentric-concentric toe-raises, and significant differences (P = 0.000-0.012) in the level of pain during CMJ, hopping, and drop CMJ. The sensitivity of the test battery at a 90% capacity was 88. Achilles tendinopathy causes not only pain and symptoms in patients but also apparent impairments in various aspects of lower leg muscle-tendon function as measured with the test battery. This test battery is reliable and able to detect differences in lower leg function between the injured or "most symptomatic" and non-injured or "least symptomatic" side in patients with Achilles tendinopathy. The test battery has higher demand on patients' function compared with each individual test.

Use of IMS data and its potential for research through global noble gases concentration maps

NASA Astrophysics Data System (ADS)

Terzi, Lucrezia; Kalinowski, Martin; Gueibe, Christophe; Camps, Johan; Gheddou, Abdelhakim; Kusmierczyk-Michulec, Jolanta; Schoeppner, Michael

2017-04-01

The Comprehensive Nuclear-Test-Ban Treaty (CTBT) established for verification purposes a global monitoring system for atmospheric radioisotopes and noble gas radioactivity. Daily activity concentrations have been collected worldwide for over 15 years providing unique data sets with long term time series that can be used for atmospheric circulation dynamics analysis. In this study, we want to emphasize the value of worldwide noble gas data by reconstructing global xenon concentration maps and comparing these observations with ATM simulations. By creating a residual plot, we can improve our understanding of our source estimation level for each region.

Low unesterified:esterified eicosapentaenoic acid (EPA) plasma concentration ratio is associated with bipolar disorder episodes, and omega-3 plasma concentrations are altered by treatment.

PubMed

Saunders, Erika Fh; Reider, Aubrey; Singh, Gagan; Gelenberg, Alan J; Rapoport, Stanley I

2015-11-01

Omega (n)-3 and n-6 polyunsaturated fatty acids (PUFAs) are molecular modulators of neurotransmission and inflammation. We hypothesized that plasma concentrations of n-3 PUFAs would be lower and those of n-6 PUFAs higher in subjects with bipolar disorder (BD) compared to healthy controls (HCs), and would correlate with symptom severity in subjects with BD, and that effective treatment would correlate with increased n-3 but lower n-6 PUFA levels. Additionally, we explored clinical correlations and group differences in plasma levels of saturated and monounsaturated fatty acids. This observational, parallel group study compared biomarkers between HCs (n = 31) and symptomatic subjects with BD (n = 27) when ill and after symptomatic recovery (follow-up). Plasma concentrations of five PUFAs [linoleic acid (LA), arachidonic acid (AA), alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA)], two saturated fatty acids (palmitic acid and stearic acid) and two monounsaturated fatty acids (palmitoleic acid and oleic acid) were measured in esterified (E) and unesterified (UE) forms. Calculated ratios included UE:E for the five PUFAs, ratios of n-3 PUFAs (DHA:ALA, EPA:ALA and EPA:DHA), and the ratio of n-6:n-3 AA:EPA. Comparisons of plasma fatty acid levels and ratios between BD and HC groups were made with Student t-tests, and between the BD group at baseline and follow-up using paired t-tests. Comparison of categorical variables was performed using chi-square tests. Pearson's r was used for bivariate correlations with clinical variables, including depressive and manic symptoms, current panic attacks, and psychosis. UE EPA was lower in subjects with BD than in HCs, with a large effect size (Cohen's d = 0.86, p < 0.002); however, it was not statistically significant after correction for multiple comparisons. No statistically significant difference was seen in any plasma PUFA concentration between the BD and HC groups after Bonferroni correction for 40 comparisons, at p < 0.001. Neither depressive severity nor mania severity was correlated significantly with any PUFA concentration. Exploratory comparison showed lower UE:E EPA in the BD than the HC group (p < 0.0001). At follow-up in the BD group, UE, E DHA:ALA, and UE EPA:ALA were decreased (p < 0.002). Exploratory correlations of clinical variables revealed that mania severity and suicidality were positively correlated with UE:E EPA ratio, and that several plasma levels and ratios correlated with panic disorder and psychosis. Depressive severity was not correlated with any ratio. No plasma fatty acid level or ratio correlated with self-reported n-3 PUFA intake or use of medication by class. A large effect size of reduced UE EPA, and a lower plasma UE:E concentration ratio of EPA in the symptomatic BD state may be important factors in vulnerability to a mood state. Altered n-3 PUFA ratios could indicate changes in PUFA metabolism concurrent with symptom improvement. Our findings are consistent with preclinical and postmortem data and suggest testing interventions that increase n-3 and decrease n-6 dietary PUFA intake. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Treatment of highly concentrated tannery wastewater using electrocoagulation: Influence of the quality of aluminium used for the electrode.

PubMed

Elabbas, S; Ouazzani, N; Mandi, L; Berrekhis, F; Perdicakis, M; Pontvianne, S; Pons, M-N; Lapicque, F; Leclerc, J-P

2016-12-05

This paper deals with the ability of electrocoagulation (EC) to remove simultaneously COD and chromium from a real chrome tanning wastewater in a batch stirred electro-coagulation cell provided with two aluminium-based electrodes (aluminium/copper/magnesium alloy and pure aluminium). Effects of operating time, current density and initial concentration of Cr(III) and COD have been investigated. The concentrations of pollutants have been successfully reduced to environmentally acceptable levels even if the concentrated effluent requires a long time of treatment of around 6h with a 400A/m(2) current density. The aluminium alloy was found to be more efficient than pure aluminium for removal of COD and chromium. Dilution of the waste has been tested for treatment: high abatement levels could be obtained with shorter time of treatment and lower current densities. Energy consumption of the electrocoagulation process was also discussed. The dilution by half of the concentrated waste leads to a higher abatement performance of both COD and chromium with the best energy efficiency. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of fluctuating temperature and food availability on reproduction and lifespan.

PubMed

Schwartz, Tonia S; Pearson, Phillip; Dawson, John; Allison, David B; Gohlke, Julia M

2016-12-15

Experimental studies on energetics and aging often remove two major factors that in part regulate the energy budget in a normal healthy individual: reproduction and fluctuating environmental conditions that challenge homeostasis. Here we use the cyclical parthenogenetic Daphnia pulex to evaluate the role of a fluctuating thermal environment on both reproduction and lifespan across six food concentrations. We test the hypotheses that (1) caloric restriction extends lifespan; (2) maximal reproduction will come with a cost of shortened lifespan; and (3) at a given food concentration, relative to a metabolically equivalent constant temperature environment a diel fluctuating thermal environment will alter the allocation of energy to reproduction and lifespan to maintain homeostasis. We did not identify a level of food concentration that extended lifespan in response to caloric restriction, and we found no cost of reproduction in terms of lifespan. Rather, the individuals at the highest food levels generally had the highest reproductive output and the longest lifespans, the individuals at the intermediate food level decreased reproduction and maintained lifespan, and the individuals at the three lower food concentrations had a decrease in reproduction and lifespan as would be predicted with increasing levels of starvation. Fluctuating temperature had no effect on lifespan at any food concentration, but delayed time to reproductive maturity and decreased early reproductive output at all food concentrations. This suggests that a fluctuating temperature regimen activates molecular pathways that alter energy allocation. The costs of fluctuating temperature on reproduction were not consistent across the lifespan. Statistical interactions for age of peak reproduction and lifetime fecundity suggest that senescence of the reproductive system may vary between temperature regimens at the different food concentrations. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of fluctuating temperature and food availability on reproduction and lifespan

PubMed Central

Schwartz, Tonia S.; Pearson, Phillip; Dawson, John; Allison, David B.; Gohlke, Julia M.

2016-01-01

Experimental studies on energetics and aging often remove two major factors that in part regulate the energy budget in a normal healthy individual: reproduction and fluctuating environmental conditions that challenge homeostasis. Here we use the cyclical parthenogenetic Daphnia pulex to evaluate the role of a fluctuating thermal environment on both reproduction and lifespan across six food concentrations. We test the hypotheses that (1) caloric restriction extends lifespan; (2) maximal reproduction will come with a cost of shortened lifespan; and (3) at a given food concentration, relative to a metabolically equivalent constant temperature environment a diel fluctuating thermal environment will alter the allocation of energy to reproduction and lifespan to maintain homeostasis. We did not identify a level of food concentration that extended lifespan in response to caloric restriction, and we found no cost of reproduction in terms of lifespan. Rather, the individuals at the highest food levels generally had the highest reproductive output and the longest lifespans, the individuals at the intermediate food level decreased reproduction and maintained lifespan, and the individuals at the three lower food concentrations had a decrease in reproduction and lifespan as would be predicted with increasing levels of starvation. Fluctuating temperature had no effect on lifespan at any food concentration, but delayed time to reproductive maturity and decreased early reproductive output at all food concentrations. This suggests that a fluctuating temperature regimen activates molecular pathways that alter energy allocation. The costs of fluctuating temperature on reproduction were not consistent across the lifespan. Statistical interactions for age of peak reproduction and lifetime fecundity suggest that senescence of the reproductive system may vary between temperature regimens at the different food concentrations. PMID:27364192

Hormonal responses during a prolonged military field exercise with variable exercise intensity.

PubMed

Kyröläinen, Heikki; Karinkanta, Jari; Santtila, Matti; Koski, Harri; Mäntysaari, Matti; Pullinen, Teemu

2008-03-01

The purpose of the present study was to test the hypothesis that the magnitude of hormonal concentration alterations during a prolonged military field exercise with constant energy intake (EI) is influenced by changes in energy deficit (ED) induced by varying the exercise intensity. Basal serum hormone concentrations were measured in a group of healthy young male volunteers (n = 7) during a 20-day field exercise. During the first week of the exercise, the average ED was 4,000 kcal/day (P-I), in the second week only 450 kcal/day (P-II), and in the last week 1,000 kcal/day (P-III). During the first 5 days of the field exercise, significant increases in cortisol (COR, +32%) and growth hormone (GH, +616%) concentrations were observed, while insulin (INS, -70%), total testosterone (TES, -27%), free testosterone (TES(free), -26%) decreased. However, after these initial responses, COR and GH returned to the pre-exercise level by the beginning of P-II. Also TES and TES(free) recovered to the pre-exercise level by the beginning of P-III, and INS by the end of P-III. The concentration of TES (+29%) increased above the pre-exercise level by the beginning of P-III. Serum thyroxin (T(4)) concentration was significantly lesser (-12%) and urine urea concentration significantly higher (+78%) after the field exercise than before it. Therefore, it can be concluded that the lower levels of ED in the second and third phase (ED <1,000 kcal/day) allowed recovery of hormonal changes observed in the first phase with ED much greater than 1,000 kcal/day.

Use of sediment-trace element geochemical models for the identification of local fluvial baseline concentrations

USGS Publications Warehouse

Horowitz, A.J.; Elrick, K.A.; Demas, C.R.; Demcheck, D.K.

1991-01-01

Studies have demonstrated the utility of fluvial bed sediment chemical data in assesing local water-quality conditions. However, establishing local background trace element levels can be difficult. Reference to published average concentrations or the use of dated cores are often of little use in small areas of diverse local petrology, geology, land use, or hydrology. An alternative approach entails the construction of a series of sediment-trace element predictive models based on data from environmentally diverse but unaffected areas. Predicted values could provide a measure of local background concentrations and comparison with actual measured concentrations could identify elevated trace elements and affected sites. Such a model set was developed from surface bed sediments collected nationwide in the United States. Tests of the models in a small Louisiana basin indicated that they could be used to establish local trace element background levels, but required recalibration to account for local geochemical conditions outside the range of samples used to generate the nationwide models.

Mycobacterium massiliense BRA100 strain recovered from postsurgical infections: resistance to high concentrations of glutaraldehyde and alternative solutions for high level disinfection.

PubMed

Lorena, Nádia Suely de Oliveira; Pitombo, Marcos Bettini; Côrtes, Patrícia Barbur; Maya, Maria Cristina Araújo; Silva, Marlei Gomes da; Carvalho, Ana Carolina da Silva; Coelho, Fábrice Santana; Miyazaki, Neide Hiromi Tokumaru; Marques, Elizabeth Andrade; Chebabo, Alberto; Freitas, Andréa D'Avila; Lupi, Otília; Duarte, Rafael Silva

2010-10-01

To evaluate the minimum inhibitory concentration (MIC) of GTA against these microorganisms and alternative disinfectants for high-level disinfection (HLD). Reference mycobacteria and clinical M. massiliense strains were included in this study. Active cultures were submitted to susceptibility qualitative tests with GTA dilutions (ranging from 1.5% to 8%), and commercial orthophthaldehyde (OPA) and peracetic acid (PA)-based solutions, during the period of exposure as recommended by National Agency of Sanitary Surveillance for HLD. All reference and M. massiliense non-BRA100 strains, recovered from sputum, were susceptible to any GTA concentration, OPA and PA solutions. M. massiliense BRA100 strains presented MIC of 8% GTA and were susceptible to OPA and PA. M. massiliense BRA100 strain is resistant to high GTA concentrations (up to 7%), which proves that this product is non-effective against specific rapidly growing mycobacteria and should be substituted by OPA or PA-based solutions for HLD.

Comparison of methods for the concentration of suspended sediment in river water for subsequent chemical analysis

USGS Publications Warehouse

Horowltz, A.J.

1986-01-01

Centrifugation, settling/centrifugation, and backflush-filtration procedures have been tested for the concentration of suspended sediment from water for subsequent trace-metal analysis. Either of the first two procedures is comparable with in-line filtration and can be carried out precisely, accurately, and with a facility that makes the procedures amenable to large-scale sampling and analysis programs. There is less potential for post-sampling alteration of suspended sediment-associated metal concentrations with the centrifugation procedure because sample stabilization is accomplished more rapidly than with settling/centrifugation. Sample preservation can be achieved by chilling. Suspended sediment associated metal levels can best be determined by direct analysis but can also be estimated from the difference between a set of unfiltered-digested and filtered subsamples. However, when suspended sediment concentrations (<150 mg/L) or trace-metal levels are low, the direct analysis approach makes quantitation more accurate and precise and can be accomplished with simpler analytical procedures.

The relationship between salivary histatin levels and oral yeast carriage.

PubMed

Jainkittivong, A; Johnson, D A; Yeh, C K

1998-06-01

Candida species are common commensal inhabitants of the oral cavity. Human saliva contains antifungal proteins called histatins. We tested the hypothesis that oral yeast status is related to salivary histatin levels. Thirty subjects were divided into two groups based on the presence (n = 15) or absence (n = 15) of yeast on oral mucosa surfaces. Unstimulated and stimulated submandibular and sublingual and parotid saliva was collected from each subject. Salivary flow rates were measured and histatin concentrations were determined in the stimulated saliva samples. The yeast colony positive group showed lower median unstimulated parotid saliva flow rates as well as lower median concentrations of total histatins in submandibular and sublingual saliva. There was a negative correlation between yeast colony-forming units and unstimulated parotid saliva flow rates and between yeast colony-forming units and submandibular and sublingual saliva histatin concentration and secretion. The results suggest that oral yeast status may be influenced by unstimulated parotid saliva flow rates and by submandibular and sublingual histatin concentration and secretion.

Hyperferritinemia in Dogs with Splenic Hemangiosarcoma

PubMed Central

CHIKAZAWA, Seishiro; HORI, Yasutomo; HOSHI, Fumio; KANAI, Kazutaka; ITO, Naoyuki; HIGUCHI, Seiichi

2013-01-01

ABSTRACT Serum ferritin concentration increases in dogs in association with various diseases. In this study, we measured serum ferritin levels in dogs with splenic masses, using a sandwich ELISA assay. Eleven dogs with hemangiosarcoma (HSA), six with hematoma, 1 with hemangioma and 3 with lymphoma were enrolled. All dogs with HSA had serum ferritin concentrations above the normal limit (1,357 ng/ml, mean + 2× standard deviation of normal). Increased serum ferritin concentrations have also been observed in few cases of hematoma, hemangioma and lymphoma. Therefore, hyperferritinemia is not specific for splenic HSA, but may have clinical usefulness as a sensitive test for the disease. Further evaluation of serum ferritin concentrations in dogs with splenic HSA is needed. PMID:23803459

Hyperferritinemia in dogs with splenic hemangiosarcoma.

PubMed

Chikazawa, Seishiro; Hori, Yasutomo; Hoshi, Fumio; Kanai, Kazutaka; Ito, Naoyuki; Higuchi, Seiichi

2013-11-01

Serum ferritin concentration increases in dogs in association with various diseases. In this study, we measured serum ferritin levels in dogs with splenic masses, using a sandwich ELISA assay. Eleven dogs with hemangiosarcoma (HSA), six with hematoma, 1 with hemangioma and 3 with lymphoma were enrolled. All dogs with HSA had serum ferritin concentrations above the normal limit (1,357 ng/ml, mean + 2× standard deviation of normal). Increased serum ferritin concentrations have also been observed in few cases of hematoma, hemangioma and lymphoma. Therefore, hyperferritinemia is not specific for splenic HSA, but may have clinical usefulness as a sensitive test for the disease. Further evaluation of serum ferritin concentrations in dogs with splenic HSA is needed.

[Establishment of Assessment Method for Air Bacteria and Fungi Contamination].

PubMed

Zhang, Hua-ling; Yao, Da-jun; Zhang, Yu; Fang, Zi-liang

2016-03-15

In this paper, in order to settle existing problems in the assessment of air bacteria and fungi contamination, the indoor and outdoor air bacteria and fungi filed concentrations by impact method and settlement method in existing documents were collected and analyzed, then the goodness of chi square was used to test whether these concentration data obeyed normal distribution at the significant level of α = 0.05, and combined with the 3σ principle of normal distribution and the current assessment standards, the suggested concentrations ranges of air microbial concentrations were determined. The research results could provide a reference for developing air bacteria and fungi contamination assessment standards in the future.

Microbial Challenge Testing of Single Liquid Cathode Feed Water Electrolysis Cells for the International Space Station (ISS) Oxygen Generator Assembly (OGA)

NASA Technical Reports Server (NTRS)

Diderich, Greg S.; Roy, Robert J.; Steele, John W.; Van Keuren, Steven P.; Wilson, Mark E.

2010-01-01

The International Space Station (ISS) Oxygen Generator Assembly (OGA) operational performance may be adversely impacted by microbiological growth and biofilm formation over the electrolysis cell membranes. Biofilms could hinder the transport of water from the bulk fluid stream to the membranes and increase the cell resistance resulting in higher cell voltages and a shorter cell life. A microbial challenge test was performed on duplicate single liquid cathode feed electrolyzer cells to evaluate operational performance with increasing levels of a mixture of five bacteria isolated from ISS and Space Shuttle potable water systems. Baseline performance of the single water electrolysis cells was determined for approximately one month with deionized water. Monthly performance was also determined following each inoculation of the feed tank with 100, 1000, 10,000 and 100,000 cells/ml of the mixed suspension of test bacteria. Water samples from the feed tank and recirculating water loops for each cell were periodically analyzed for enumeration and speciation of bacteria and total organic carbon. While initially a concern, this test program has demonstrated that the performance of the electrolysis cell is not adversely impacted by feed water containing the five species of bacteria tested at a concentration measured as high as 1,000,000 colony forming units (CFU)/ml. This paper presents the methodologies used in the conduct of this test program along with the performance test results at each level of bacteria concentration.

Current efforts on developing an HWIL synthetic environment for LADAR sensor testing at AMRDEC

NASA Astrophysics Data System (ADS)

Kim, Hajin J.; Cornell, Michael C.; Naumann, Charles B.

2005-05-01

Efforts in developing a synthetic environment for testing LADAR sensors in a hardware-in-the-loop simulation are continuing at the Aviation and Missile Research, Engineering, and Development Center (AMRDEC) of the U.S. Army Research, Engineering and Development Command (RDECOM). Current activities have concentrated on developing the optical projection hardware portion of the synthetic environment. These activities range from system level design down to component level testing. Of particular interest have been schemes for generating the optical signals representing the individual pixels of the projection. Several approaches have been investigated and tested with emphasis on operating wavelength, intensity dynamic range and uniformity, and flexibility in pixel waveform generation. This paper will discuss some of the results from these current efforts at RDECOM's Advanced Simulation Center (ASC).

Ketamine coadministration attenuates morphine tolerance and leads to increased brain concentrations of both drugs in the rat

PubMed Central

Lilius, T O; Jokinen, V; Neuvonen, M S; Niemi, M; Kalso, E A; Rauhala, P V

2015-01-01

Background and Purpose The effects of ketamine in attenuating morphine tolerance have been suggested to result from a pharmacodynamic interaction. We studied whether ketamine might increase brain morphine concentrations in acute coadministration, in morphine tolerance and morphine withdrawal. Experimental Approach Morphine minipumps (6 mg·day–1) induced tolerance during 5 days in Sprague–Dawley rats, after which s.c. ketamine (10 mg·kg–1) was administered. Tail flick, hot plate and rotarod tests were used for behavioural testing. Serum levels and whole tissue brain and liver concentrations of morphine, morphine-3-glucuronide, ketamine and norketamine were measured using HPLC-tandem mass spectrometry. Key Results In morphine-naïve rats, ketamine caused no antinociception whereas in morphine-tolerant rats there was significant antinociception (57% maximum possible effect in the tail flick test 90 min after administration) lasting up to 150 min. In the brain of morphine-tolerant ketamine-treated rats, the morphine, ketamine and norketamine concentrations were 2.1-, 1.4- and 3.4-fold, respectively, compared with the rats treated with morphine or ketamine only. In the liver of morphine-tolerant ketamine-treated rats, ketamine concentration was sixfold compared with morphine-naïve rats. After a 2 day morphine withdrawal period, smaller but parallel concentration changes were observed. In acute coadministration, ketamine increased the brain morphine concentration by 20%, but no increase in ketamine concentrations or increased antinociception was observed. Conclusions and Implications The ability of ketamine to induce antinociception in rats made tolerant to morphine may also be due to increased brain concentrations of morphine, ketamine and norketamine. The relevance of these findings needs to be assessed in humans. PMID:25297798

Design of a sediment data-collection program in Kansas as affected by time trends

USGS Publications Warehouse

Jordan, P.R.

1985-01-01

Data collection programs need to be re-examined periodically in order to insure their usefulness, efficiency, and applicability. The possibility of time trends in sediment concentration, in particular, makes the examination with new statistical techniques desirable. After adjusting sediment concentrations for their relation to streamflow rates and by using a seasonal adaptation of Kendall 's nonparametric statistical test, time trends of flow-adjusted concentrations were detected for 11 of the 38 sediment records tested that were not affected by large reservoirs. Ten of the 11 trends were toward smaller concentrations; only 1 was toward larger concentrations. Of the apparent trends that were not statistically significant (0.05 level) using data available, nearly all were toward smaller concentrations. Because the reason for the lack of statistical significance of an apparent trend may be inadequacy of data rather than absence of trend and because of the prevalence of apparent trends in one direction, the assumption was made that a time trend may be present at any station. This assumption can significantly affect the design of a sediment data collection program. Sudden decreases (step trends) in flow-adjusted sediment concentrations were found at all stations that were short distances downstream from large reservoirs and that had adequate data for a seasonal adaptation of Wilcoxon 's nonparametric statistical test. Examination of sediment records in the 1984 data collection program of the Kansas Water Office indicated 13 stations that can be discontinued temporarily because data are now adequate. Data collection could be resumed in 1992 when new data may be needed because of possible time trends. New data are needed at eight previously operated stations where existing data may be inadequate or misleading because of time trends. Operational changes may be needed at some stations, such as hiring contract observers or installing automatic pumping samplers. Implementing the changes in the program can provide a substantial increase in the quantity of useful information on stream sediment for the same funding as the 1984 level. (Author 's abstract)

Mexican Origin Youths’ Trajectories of Perceived Peer Discrimination from Middle Childhood to Adolescence: Variation by Neighborhood Ethnic Concentration

PubMed Central

White, Rebecca M. B.; Zeiders, Katharine H.; Knight, George P.; Roosa, Mark W.; Tein, Jenn-Yun

2014-01-01

Developmentally salient research on perceived peer discrimination among minority youths is limited. Little is known about trajectories of perceived peer discrimination across the developmental period ranging from middle childhood to adolescence. Ethically concentrated neighborhoods are hypothesized to protect minority youths from discrimination, but strong empirical tests are lacking. The first aim of the current study was to estimate trajectories of perceived peer discrimination from middle childhood to adolescence, as youths transitioned from elementary to middle and to high school. The second aim was to examine the relationship between neighborhood ethnic concentration and perceived peer discrimination over time. Using a diverse sample of 749 Mexican origin youths (48.9% female), a series of growth models revealed that youths born in Mexico, relative to those born in the U.S., perceived higher discrimination in the 5th grade and decreases across time. Youths who had higher averages on neighborhood ethnic concentration (across the developmental period) experienced decreases in perceived peer discrimination over time; those that had lower average neighborhood ethnic concentration levels showed evidence of increasing trajectories. Further, when individuals experienced increases in their own neighborhood ethnic concentration levels (relative to their own cross-time averages), they reported lower levels of perceived peer discrimination. Neighborhood ethnic concentration findings were not explained by the concurrent changes youths were experiencing in school ethnic concentrations. The results support a culturally-informed developmental view of perceived peer discrimination that recognizes variability in co-ethnic neighborhood contexts. The results advance a view of ethnic enclaves as protective from mainstream threats. PMID:24488094