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Sample records for two-generation laboratory study

  1. Two-generation reproduction toxicity study in rats with methoxychlor.

    Science.gov (United States)

    Aoyama, Hiroaki; Hojo, Hitoshi; Takahashi, Ken L; Shimizu-Endo, Naoko; Araki, Masayuki; Takeuchi-Kashimoto, Yukiko; Saka, Machiko; Teramoto, Shoji

    2012-03-01

    A two-generation reproduction toxicity study was conducted in rats with a reference estrogenic pesticide, methoxychlor, to validate the sensitivity and competency of current guidelines recommended by the United States Environmental Protection Agency; Japanese Ministry of Agriculture, Forestry and Fisheries; and Organisation for Economic Co-operation and Development for predicting reproductive toxicity of the test compound based on estrogenic endocrine disrupting effects. Both sexes of SD rats were exposed to methoxychlor in the diet at concentrations of 0, 10, 500 and 1500 ppm for two successive generations. The present study has successfully detected estrogenic activities and reproductive toxicities of methoxychlor, as well as its systemic toxicity. Body weights, body weight gains and food consumption of both sexes of animals were suppressed significantly in the 500 and 1500 ppm groups. Typical reproductive toxicities observed in females of these groups included, but were not limited to, prolonged estrous cycle, reduced fertility, decreased numbers of implantation sites and newborns, decreased ovary weights and/or increased incidences of cystic ovary. Uterine weights of weanlings increased significantly in these groups, suggesting that the sensitivity of this parameter for predicting estrogenic ability of the test compound is comparable to that of the uterotrophic assay. Reproductive toxicities of methoxychlor seemed less potent in males than in females. Methoxychlor delayed preputial separation and significantly reduced sperm counts and reproductive organ weights of males of the 500 and/or 1500 ppm groups; however, most males that failed to impregnate females in the same group showed normal fertility when they were re-mated with untreated females. Neither systemic nor reproductive toxicities appeared in the 10 ppm group.

  2. Rebaudioside A: two-generation reproductive toxicity study in rats.

    Science.gov (United States)

    Curry, Leslie L; Roberts, Ashley; Brown, Nigel

    2008-07-01

    Rebaudioside A was administered via the diet to male and female Han Wistar rats at 0, 7500, 12,500, and 25,000ppm for two generations. Rebaudioside A treatment was not associated with any signs of clinical toxicity or adverse effects on body weight, body weight gain, or food consumption. No treatment-related effects of rebaudioside A were observed in either the F0 or F1 generations on reproductive performance parameters including mating performance, fertility, gestation lengths, oestrous cycles, or sperm motility, concentration, or morphology. The survival and general condition of the F1 and F2 offspring, their pre-weaning reflex development, overall body weight gains, and the timing of sexual maturation, were not adversely affected by rebaudioside A treatment. The NOAEL for reproductive effects was 25,000ppm and the NOAEL for the survival, development, and general condition of the offspring also was considered to be 25,000ppm or 2048-2273mg/kg body weight/day.

  3. Population study of fears in two generations of Ukrainians

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    O V Filiptsova

    2015-01-01

    Full Text Available Aim: Fear is an ancient natural reaction of a human being to a threat and it is also an adaptive feature. Obsessive fear can transfer into phobias, which lead to a clinical problem. In spite of many studies done on fear, many questions are yet not clarified. In the former Soviet Union, research on human behaviour traits was mostly tabooed. The current research will fill some gaps on the ′behavioural map′ of Ukraine in relationship to fear distributions in two successive generations of residents of Ukraine. Subjects and Methods: Eight hundred and sixty-seven residents of Ukraine, predominantly residents of Kharkov and Kharkov region participated in the study. All participants were distributed into groups of younger and older generations. Twenty-four emotional states of fear have been studied by Ivleva-Shcherbatyh questionnaire, developed and validated in Slavs samples. Results: The population analysis of 24 types of fear has shown that sex differences were found mostly among members of the younger generation. The average value of sex differences from the amplitude trait of variation made up approximately 20%. More significant differences between members of different generations have been found in females. The age dynamics of fears within each generation has been detected. Conclusions: The population analysis of fears in Ukraine has demonstrated that the strongest fears independently of the generation were related to diseases of relatives and to problems in the case of diseases of relatives.

  4. Methylene chloride: two-generation inhalation reproductive study in rats

    Energy Technology Data Exchange (ETDEWEB)

    Nitschke, K.D.; Eisenbrandt, D.L.; Lomax, L.G.; Rao, K.S.

    1988-07-01

    Reproductive parameters in Fischer 344 rats were evaluated following inhalation of methylene chloride (MeCl/sub 2/) for two successive generations. Thirty male and female rats were exposed to 0, 100, 500, or 1500 ppm MeCl/sub 2/ for 6 hr/day, 5 days/week for 14 weeks and then mated to produce f1 litters. After weaning, 30 randomly selected f1 pups/sex/group were exposed to MeCl/sub 2/ for 17 weeks and subsequently mated to produce f2 litters. Reproductive parameters examined included fertility, litter size and neonatal growth, and survival. All adults and selected weanlings were examined for grossly visible lesions. Tissues from selected weanlings were examined histopathologically. No adverse effects on reproductive parameters, neonatal survival, or neonatal growth were noted in animals exposed to methylene chloride in either the f0 or f1 generations. Similarly, there were no treatment-related gross pathologic observations in f0 or f1 adults or f1 and f2 weanlings. Histopathologic examination of tissues from f1 and f2 weanlings did not reveal any lesions attributed to methylene chloride. Thus, exposure of rats to concentrations as high as 1500 ppm methylene chloride, which has been shown in a 2-year study to produce treatment-related effects, did not affect any reproductive parameters.

  5. Sensitive endpoints in extended one-generation reproductive toxicity study versus two generation?

    DEFF Research Database (Denmark)

    Christiansen, Sofie

    during critical period of development in contrast to the parental generation. Retrospective analysis of available two-generation studies, however, indicate that the assessment included in the study of other endpoints in the male offspring such as histopathology of reproductive organs and semen quality...... receives considerable attention, as it is the only OECD test guideline whereby an organism is exposed during the whole of development, from gamete stage through sexual development. The one-generation study design from 1983, OECD TG 415, is not a standard information requirement under REACH and is often...... largely disfavoured because it does not cover the full reproductive cycle, and has not been updated with the developing science. A new study design, EOGRTS, for evaluation of the reproductive toxicity of pesticides and chemicals is currently being evaluated for adoption by OECD and may replace the two...

  6. Potassium Dichromate Impact on Male Reproductive Integrity Biomarker in Rat. Two Generation Study

    Directory of Open Access Journals (Sweden)

    Jelena Rankov

    2010-05-01

    Full Text Available The aim of this study was the evaluation of Cr VI cumulative and differentiate exposure on integrity biomarker of male reproductive system. The objective was evaluation of potassium dichromate intake on genital organs and sexual accessory glands architecture in male rats from two generation. Males and females from F0 generation were exposed to potassium dichromate three months before mating. F1 generation was represented by male pups, resulted from F0 generation, exposed to potassium dichromate in utero, during suckling (via milk and water period and until sexual maturity. All the animals were divided in one control and three experimental groups, exposed to Cr VI trough drinking water, as followed E1: 25 ppm (LOAEL; E2: 50 ppm: E3: 75 ppm; control group received tap water without chromium content. The experiment was carried out with respecting legislation regarding ethics in animal experiments. The study revealed the presence of congestive and degenerative lesions in genital organs and sexual accessory glands of exposed individuals from F0 and F1 generation such as: interstitial edema, epithelial necrosis and atrophy, membrane exfoliation and necrosis. The lesions frequency and intensity were directly correlated to exposure level, the most affected being E3 group and generation, more pronounced in F1 generation.

  7. Testosterone and LH Seric Level Dynamics in Male Rats after Potassium Dichromate Intake (Two Generation Study

    Directory of Open Access Journals (Sweden)

    Jelena Rankov

    2010-05-01

    Full Text Available The aim of this study was the evaluation of potassium dichromate impact on biochemical biomarkers for testicular function (serum testosterone and LH level (two generations experiment. Males and females from F0 generation were exposed to potassium dichromate three months before mating. F1 generation was represented by male pups, resulted from F0 generation, exposed to potassium dichromate in utero, in suckling period (via milk and water and until sexual maturity. All the animals were divided in four groups: three experimental and one control, exposed to Cr VI trough drinking water, as follows E1: 25 ppm (LOAEL; E2: 50 ppm: E3: 75 ppm; control group received tap water without chromium content. The study was performed in compliance with national and international law regarding animal welfare and ethics in animal experiments. In male rats, from F0 and F1 generation, exposure to Cr VI determined: significant decrease of testosterone and significant increase of LH seric level in all experimental groups comparative to control one, indirectly, respectively, directly correlated to exposure level. Comparative to F0 generation, in F1 generation seric testosterone level was lower, significantly only in E1 and E3 groups, and LH seric level was significantly higher.

  8. Two-generation reproduction and teratology studies of feeding aditoprim in Wistar rats.

    Science.gov (United States)

    Wang, Xu; Tan, Ziqiang; Cheng, Guyue; Awais, Ihsan; Huang, Lingli; Chen, Dongmei; Pan, Yuanhu; Liu, Zhenli; Yuan, Zonghui

    2015-12-01

    Aditoprim, a new bacteriostatic agent that belongs to diaminopyrimidines, has a broad antimicrobial spectrum, good antibacterial activity and excellent pharmacokinetics. To evaluate the reproductive toxicity and teratogenic potential of aditoprim, different concentrations of aditoprim were administered to Wistar rats by feeding diets containing 0, 20, 100 and 1000 mg kg(-1) , respectively. Each group consisting of 18 males and 25 females (F0 ) was treated with different concentrations of aditoprim through a 13-week period before mating and during mating, gestation, parturition and lactation. At weaning, 20 males and 25 females of the F1 generation weanlings per group were selected randomly as parents for the F2 generation. Selected F1 weanlings were exposed to the same diet and treatment as their parents. At 1000 mg kg(-1) dose group, body weights in F0 and F1 rats, fetal body weight on day 21 (0, 4 and 21) after birth and number of viable fetuses in the F0 and F1 generation significantly decreased. Teratogenicity study was performed in combination with the F1 generation of a two-generation reproduction study. F1 parents of the reproduction study were mated after weaning of the F2a pups. Pregnant female rats were subjected to cesarean section on gestational day 20 for teratogenic examination. At 1000 mg kg(-1) group, body weights, fetal body lengths, tail lengths, litter weights and number of viable fetuses were significantly decreased. No obvious external, skeletal or visceral malformations in fetuses were noted in any groups in the teratogenic test. The no-observed-adverse-effect level for reproduction/development toxicity of aditoprim was 100 mg kg(-1) diet (about 7.89-9.25 mg kg(-1) body weight day(-1) ).

  9. Awareness and Attitude towards Breastfeeding among Two Generations of Indian Women: A Comparative Study.

    Directory of Open Access Journals (Sweden)

    Deeksha Pandey

    Full Text Available Present study was aimed to analyze the impact of education, employment and financial independence in breastfeeding practices among Indian women.Present explorative questionnaire based survey included 256 women (128 pairs in the final analysis. A pair means--a pregnant lady (in her third trimester representing younger generation and b her mother/mother in law representing the elder generation.We found that the overall awareness regarding 'breast milk' being the best food for baby was excellent (overall 97.3%; younger generation: 96.9%; elder generation: 97.7%. Overall knowledge regarding the correct technique (28.9% younger generation and 21.9% elder generation and frequency of breastfeeding (20.3% of younger generation and 34.4% of elder generation was very poor. Less than 60% (younger generation: 57.8%; elder generation: 58.6% were aware that the only major contraindication for breastfeeding is a mother infected with human immunodeficiency virus (HIV. On comparing responses obtained from the two generations of women, difference was not statistically significant among most of the issues related to breastfeeding. With regards to the attitude, despite better awareness, only 94.5% women in younger generation and 89.1% women in elder generation were planning to give mother's milk as the first feed to the newborn. Similarly, less than 75% of women were ready to breast-feed the newborn immediately after birth. This was contradictory to the fact that 86% of pregnant women were aware that the baby should be breast-fed within an hour of birth.Awareness with regards to breastfeeding issues had not changed significantly with the educational progress of Indian women. Despite the good level of awareness in the society regarding breastfeeding, attitude to practice the same is lacking.

  10. Oral (gavage) two-generation (one litter per generation) reproduction study of pentachlorophenol (penta) in rats.

    Science.gov (United States)

    Bernard, Bruce K; Hoberman, Alan M; Brown, W Ray; Ranpuria, Anish K; Christian, Mildred S

    2002-01-01

    The potential for pentachlorophenol (penta) to induce general and reproductive/developmental toxicity was evaluated in Crl Sprague-Dawley rats, employing a two-generation reproduction toxicity study. Penta was administered by gavage at doses of 0, 10, 30, and 60 mg/kg/day. In both generations, the parental animals (30/sex/group) were intubated daily for 10 weeks before cohabitation and continuing through cohabitation, gestation, and lactation periods. Intubation of the F1 generation was begun 28 days postpartum. Animals were evaluated daily for mortality and general toxicity (clinical observations, body weights and gains, feed consumption). Organ weights were recorded and histopathological evaluations were made. Specific indices of reproductive function evaluated included estrous cycles, mating and fertility, parturition, lactation, viability, and growth and development of offspring, including sexual maturation, sperm parameters, and numbers of ovarian primordial follicles. All deaths in the parental rats were unrelated to penta. Expected metabolic effects of penta, sporadic increased liver weights associated with hepatocellular centrilobular hypertrophy and vacuolation and lipofuscin pigmentation, were evident in the 10-, 30-, and 60-mg/kg/day dose group P1 and F1 animals. Toxicity, in the form of liver pathology (single cell necrosis), reduced body weights and associated reductions in organ weights, and reduced feed consumption were noted in both generations at the 30- and 60-mg/kg/day doses. Developmental toxicity associated with these doses included reduced pup weights and viability. The 60-mg/kg/day dose also resulted in delayed sexual maturation, decreased spermatid counts, small prostates and testes, decreased implantations, reduced fertility, and increased resorptions of embryos. Based on these results, it was concluded that 30 mg/kg/day is the lowest-observable-adverse-effect level (LOAEL) and 10 mg/kg/day is the no-observable-adverse-effect level (NOAEL

  11. Two-generation reproduction and developmental neurotoxicity study with sodium chlorite in the rat.

    Science.gov (United States)

    Gill, M W; Swanson, M S; Murphy, S R; Bailey, G P

    2000-01-01

    The potential for sodium chlorite to produce reproductive toxicity, developmental neurotoxicity and alterations in hematology and thyroid hormones was evaluated in Sprague-Dawley rats administered sodium chlorite in the drinking water continuously for two generations. The F(0) generation animals (30 of each gender per group) and F(1) generation animals (25 of each gender per group) selected to rear the F(2) generation were allowed free access to drinking water containing 0, 35, 70 or 300 ppm sodium chlorite for a 10-week prebreed period, through mating for males and through mating, gestation and lactation for females. These drinking water concentrations corresponded to sodium chlorite doses of approximately 4, 8 and 30 mg kg(-1) day(-1) for males and 5, 10 and 39 mg kg(-1) day(-1) for females, respectively. Evaluations included standard reproductive and postnatal indices, sperm morphology and motility, estrous cyclicity, a functional observational battery, motor activity, auditory startle, swim maze, hematology, serum thyroid hormone analyses and histopathology of reproductive and nervous system tissues. Sodium chlorite resulted in a decrease in water consumption in all groups and a decrease in food consumption and body weights in the 70 and 300 ppm groups. There was no evidence of reproductive toxicity. Pup body weight was decreased in the 300 ppm group and small delays were observed in the time to preputial separation and vaginal opening. Mild anemia and mild methemoglobinemia were observed for animals in the 300 ppm group. Thyroid hormone levels were not affected by treatment. Changes to the nervous system were limited to small decreases in amplitude of auditory startle response for postnatal day (PND) 25 pups in the 70 and 300 ppm groups and a small decrease in absolute brain weight for PND 11 pups in the 300 ppm group. These effects were considered to be of questionable neurotoxicological significance. Based on the results of this study, the no

  12. Two generation reproduction and teratogenicity studies of feeding cyadox in Wistar rats.

    Science.gov (United States)

    Wang, Xu; Fang, Gui-Jie; Wang, Yu-Lian; Ihsan, Awais; Huang, Ling-Li; Zhou, Wen; Liu, Zhen-Li; Yuan, Zong-Hui

    2011-05-01

    To investigate the teratogenic potential and reproductive toxicity of cyadox, a growth promoting agent, Wistar rats (F(0)) were fed with diets containing cyadox (0, 50, 150 and 2500 mg/kg) or olaquindox (150 mg/kg), approximately equivalent to cyadox 5, 15, 250 or olaquindox 15 mg/kg b.w./day across two generations. Half of the pregnant rats (F(0), F(1b)) were subjected to caesarean section on gestational day 20 for teratogenic examination and the other half produced pups F(1a) and F(2a), respectively. At the 250 mg/kg b.w./day cyadox group, body weights of F(1b) pregnant rats and F(2a) on day 21 after birth decreased; fetal body lengths and tail lengths decreased; the number of fetal resorptions increased significantly; litter weights, number of viable fetuses decreased; number of embryo resorptions increased significantly; number of liveborn F(1a), F(1b) and F(2a) decreased. No macroscopic or microscopic change of any significance was found in the reproductive organs. Significant increases in the incidence of cervical ribs or lumbar ribs in F(2a) pups and significant increases of relative organ weight of testis and epididymis in F(1b) were observed at the 250 mg/kg b.w./day cyadox group. The NOAEL for reproduction/development of cyadox for rats was estimated to be 150 mg/kg diet, which was equivalent to approximately 15 mg/kg b.w./day.

  13. Oral two-generation reproduction toxicity study with NM-200 synthetic amorphous silica in Wistar rats

    NARCIS (Netherlands)

    Wolterbeek, A.; Oosterwijk, T.; Schneider, S.; Landsiedel, R.; Groot, D. de; Ee, R. van; Wouters, M.; Sandt, H. van de

    2015-01-01

    Synthetic amorphous silica (SAS) like NM-200 is used in a wide variety of technological applications and consumer products. Although SAS has been widely investigated the available reproductive toxicity studies are old and do not cover all requirements of current OECD Guidelines. As part of a CEFIC-L

  14. Two-generation reproductive toxicity study of plant stanol esters in rats

    NARCIS (Netherlands)

    Whittaker, M.H.; Frankos, V.H.; Wolterbeek, A.P.M.; Waalkens-Berendsen, D.H.

    1999-01-01

    Plant stanol esters are intended for use as an ingredient in food to reduce the absorption of cholesterol from the gastrointestinal tract. Consumption of plant stanol esters has a demonstrated diet-derived public health benefit, as shown by numerous clinical studies. Plant stanol esters are

  15. Two generation reproduction and teratogenicity studies of feeding quinocetone fed to Wistar rats.

    Science.gov (United States)

    Wang, Xu; Zhang, Wei; Wang, Yu-Lian; Ihsan, Awais; Dai, Meng-Hong; Huang, Ling-Li; Chen, Dong-Mei; Tao, Yan-Fei; Peng, Da-Peng; Liu, Zhen-Li; Yuan, Zong-Hui

    2012-05-01

    To investigate the reproductive toxicity and teratogenic potential of quinocetone, a growth promoting agent, Wistar rats were fed different diets containing 0, 50, 300 and 1800 mg/kg quinocetone or 300 mg/kg olaquindox. Groups of 15 males and 30 females (F(0)) were fed through a 10-week prebreed period as well as during mating, gestation, parturition and lactation. At weaning, 12 males and 24 females of F(1) generation weanlings per group were selected randomly as parents for F(2) generation. Selected F(1) weanlings were exposed to the same diet and treatment as their parents. At the highest quinocetone group, body weights in F(0) and F(1) rats, fetal body weight on day 21 after birth and number of viable fetuses in F(0) and F(1) generation significantly decreased. In teratogenicity study, groups of 12 males and 24 females were fed with the same diets through a 12-week prebreed period and matting periods. Pregnant rats were subjected to cesarean section on GD 20 for teratogenic examination. At the highest quinocetone group, body weights and feed efficiency, fetal body lengths, tail lengths, litter weights and number of viable fetuses significantly decreased. The NOAEL for reproduction/development of quinocetone for rats was estimated to be 300 mg/kg diet.

  16. Toxicology Studies on Lewisite and Sulfur Mustard Agents: Two-Generation Reproduction Study of Lewisite in Rats Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Sasser, L. B.; Cushing, J. A.; Kalkwarf, D. R.; Mellick, P. W.; Buschbom, R. L.

    1989-07-15

    Occupational health standards have not been established for Lewisite [bis(2-chlorethyl)arsine], a potent toxic vesicant which reacts with the sulfhydryl groups of proteins through its arsenic group. The purposes of this study were to determine the reproductive consequences and dose~response of continuing Lewisite exposure of parental males and females and their offspring in a 42-week two-generation study. Solutions of Lewisite were prepared for administration by diluting the neat agent with sesame oil. Rats were administered Lewisite (0, 0.10, 0.25 or 0.60 mg/kg/day for 5 days a week) via intragastric intubation prior to mating, during mating and after mating until the birth of their offspring. The dams continued to receive Lewisite during lactation. At weaning, male and female offspring of each group were selected to continue on the study; rece1v1ng Lewisite during adolescence, mating and throughout gestation. Again, the dams continued to receive Lewisite until weaning of the offspring. Lewisite had no adverse effect on reproduction performance, fertility or reproductive organ weights of male or female rats through two consecutive generations. No adverse effect to offspring were attributed to Lewisite exposure. Minor changes in growth was the only maternal effect observed. Lewisite exposure of parental rats caused no gross or microscopic lesions in testes, epididymis, prostrate, seminal vesicles, ovaries, uterus or vagina. Severe inflammation of the lung was observed at necropsy in cases in which Lewisite gained access to the respiratory system from accidental dosing or reflux and aspiration; this usually caused early death of the animal. The NOEL for reproductive effects in this study was greater than 0.60 mg/kg/day.

  17. The consequences of lead acetate intake on exposure and integrity biomarkers of reproductive system in female rats at sexual maturity (two generation study

    Directory of Open Access Journals (Sweden)

    Eugenia Dumitrescu

    2010-06-01

    Full Text Available The aim of the study was the assessment of lead toxic impact on female reproductive systemintegrity and performances biomarkers. The objectives were: the evaluation of lead levels in ovary,Fallopian tubes and uterus (exposure biomarker and the structural changes in ovary, Fallopian tubesand uterus (integrity biomarker at sexual maturity consecutive exposure to lead acetate (50, 100, 150ppb Pb in drinking water along two generation (F0, F1. The study pointed out significant increase of leadlevel in ovaries, Fallopian tubes and uterus comparative to the control group and direct corelation, withdifferent degrees of significance, with the exposure level; severe congestive and degenerative changes inovary (destruction of parenchymatosa zone, vacuolar epithelial cells, passive vascular congestion,edematous follicle without oocytes, follicle with oocytes and uterus (necrosis of uterine glands,destruction of uterine lining cells, total detachments of the superficial layers of the epithelia, hypertrophyof the epithelia.

  18. Laboratory study of TLEs

    Science.gov (United States)

    Kochkin, P.; Van Deursen, A.; Ebert, U.

    2014-12-01

    Sprites are high-altitude kilometre-scale electrical discharges that happen above thundercloud. Pilot systems are pre-breakdown phenomena that usually attributed to stepped leader development. In Eindhoven University of Technology we investigate meter-scale laboratory discharges looking for similarities with natural lightning and its related phenomena. Negative lightning possesses step-like propagation behaviour which is associated with space leader formation in front of its main leader. Meter-scale laboratory sparks also develop via formation of a space stem that transforms into a pilot system and finally develops into a space leader in longer gaps. With ns-fast photography we investigated the pilot system formation and found striking similarities with high-altitude sprites. But sprites are different in size, environment and polarity. Laboratory pilot barely reaches 70 cm and develops in STP air, while high-altitude sprites reaches ionosphere stretching for dozens of kilometres. Also sprites are assumed to be of opposite to the pilot polarity. Besides that, the pilots are directly involved in x-ray generation in long laboratory sparks. The detailed pilot system development process will be shown, in particular focusing on similarities with natural sprites. Basic properties of the x-ray emission will be presented and discussed.

  19. Acute, reproductive toxicity and two-generation teratology studies of a standardized quassinoid-rich extract of Eurycoma longifolia Jack in Sprague-Dawley rats.

    Science.gov (United States)

    Low, Bin-Seng; Das, Prashanta Kumar; Chan, Kit-Lam

    2014-07-01

    The roots of Eurycoma longifolia Jack are popularly sought as herbal medicinal supplements to improve libido and general health amongst the local ethnic population. The major quassinoids of E. longifolia improved spermatogenesis and fertility but toxicity studies have not been well documented. The reproductive toxicity, two generation of foetus teratology and the up-and-down acute toxicity were investigated in Sprague-Dawley rats orally treated with quassinoid-rich E. longifolia extract (TAF273). The results showed that the median lethal dose (LD50 ) of TAF273 for female and male rats was 1293 and >2000 mg/kg, respectively. Fertility index and litter size of the TAF273 treated were significantly increased when compared with those of the non-treated animals. The TAF273-treated dams decreased in percentage of pre-implantation loss, post-implantation loss and late resorption. No toxic symptoms were observed on the TAF273-treated pregnant female rats and their foetuses were normal. The no-observed adverse effect level (NOAEL) obtained from reproductive toxicity and teratology studies of TAF273 in rats was 100 mg/kg body weight/day, being more than 10-fold lower than the LD50 value. Thus, any human dose derived from converting the rat doses of 100 mg/kg and below may be considered as safe for further clinical studies.

  20. Bentonite erosion. Laboratory studies

    Energy Technology Data Exchange (ETDEWEB)

    Jansson, Mats (Div. of Nuclear Chemistry, Royal Inst. of Technology, Stockholm (Sweden), School of Chemical Science and Engineering)

    2009-11-15

    This report covers the laboratory studies that have been performed at Nuclear Chemistry, KTH in the project 'Bentonite Erosion'. Many of the experiments in this report were performed to support the work of the modelling group and were often relatively simple. One of the experiment series was performed to see the impact of gravity and concentration of mono- and di-valent cations. A clay suspension was prepared in a test tube. A net was placed in contact with the suspension, the test tube was filled with solutions of different concentrations and the system was left overnight to settle. The tube was then turned upside down and the behaviour was visually observed. Either the clay suspension fell through the net or stayed on top. By using this method surprisingly sharp determinations of the Critical Coagulation (Flocculation) Concentration (CCC/CFC) could be made. The CCC/CFC of Ca2+ was for sodium montmorillonite determined to be between 1 and 2 mM. An artificial fracture was manufactured in order to simulate the real case scenario. The set-up was two Plexiglas slabs separated by 1 mm thick spacers with a bentonite container at one side of the fracture. Water was pumped with a very low flow rate perpendicular to bentonite container and the water exiting the fracture was sampled and analyzed for colloid content. The bentonite used was treated in different ways. In the first experiment a relatively montmorillonite rich clay was used while in the second bentonite where only the readily soluble minerals had been removed was used. Since Plexiglas was used it was possible to visually observe the bentonite dispersing into the fracture. After the compacted bentonite (1,000 kg/m3) had been water saturated the clay had expanded some 12 mm out into the fracture. As the experiment progressed the clay expanded more out into the fracture and seemed to fractionate in two different phases with less material in the outmost phase. A dark rim which was later analyzed to contain

  1. Laboratory Plasma Studies

    Science.gov (United States)

    1993-11-30

    arrVanemat is electron beam loses an amount of energy corresponding to shown in frig. 1. The VERA pulseline accelerato (V-0.6- the capacitive voltage drop...the finite transverse disk, similar to that studied in Subsection 4.&. Over the size, how well is the diffractionless property preserved . same distance...Boeing Aerospace Lean. VA, USA. Company (RAC) is alo shown. Elsevier Science Publishers B.V. (North-Holland) IlL THEORY 9 478 C. . Rob R . Haf•z / Electron

  2. Microscale Immune Studies Laboratory.

    Energy Technology Data Exchange (ETDEWEB)

    Poschet, Jens Fredrich; Carroll-Portillo, Amanda; Wu, Meiye; Manginell, Ronald Paul; Herr, Amy Elizabeth; Martino, Anthony A.; Perroud, Thomas D.; Branda, Catherine; Srivastava, Nimisha; Sinclair, Michael B.; Moorman, Matthew Wallace; Apblett, Christopher Alan; Sale, Kenneth L.; James, Conrad D.; Carles, Elizabeth L.; Lidke, Diane S. (University of New Mexico, Albuquerque, NM); Van Benthem, Mark Hilary; Rebeil, Roberto; Kaiser, Julie; Seaman, William (University of California, San Francisco, CA); Rempe, Susan; Brozik, Susan Marie; Jones, Howland D. T.; Gemperline, Paul (East Carolina University, Greenville, NC); Throckmorton, Daniel J.; Misra, Milind; Murton, Jaclyn K.; Carson, Bryan D.; Zhang, Zhaoduo; Plimpton, Steven James; Renzi, Ronald F.; Lane, Todd W.; Ndiaye-Dulac, Elsa; Singh, Anup K.; Haaland, David Michael; Faulon, Jean-Loup Michel; Davis, Ryan W.; Ricken, James Bryce; Branda, Steven S.; Patel, Kamlesh D.; Joo, Jaewook; Kubiak, Glenn D.; Brennan, James S.; Martin, Shawn Bryan; Brasier, Allan (University of Texas Mecial Branch, Galveston, TX)

    2009-01-01

    The overarching goal is to develop novel technologies to elucidate molecular mechanisms of the innate immune response in host cells to pathogens such as bacteria and viruses including the mechanisms used by pathogens to subvert/suppress/obfuscate the immune response to cause their harmful effects. Innate immunity is our first line of defense against a pathogenic bacteria or virus. A comprehensive 'system-level' understanding of innate immunity pathways such as toll-like receptor (TLR) pathways is the key to deciphering mechanisms of pathogenesis and can lead to improvements in early diagnosis or developing improved therapeutics. Current methods for studying signaling focus on measurements of a limited number of components in a pathway and hence, fail to provide a systems-level understanding. We have developed a systems biology approach to decipher TLR4 pathways in macrophage cell lines in response to exposure to pathogenic bacteria and their lipopolysaccharide (LPS). Our approach integrates biological reagents, a microfluidic cell handling and analysis platform, high-resolution imaging and computational modeling to provide spatially- and temporally-resolved measurement of TLR-network components. The Integrated microfluidic platform is capable of imaging single cells to obtain dynamic translocation data as well as high-throughput acquisition of quantitative protein expression and phosphorylation information of selected cell populations. The platform consists of multiple modules such as single-cell array, cell sorter, and phosphoflow chip to provide confocal imaging, cell sorting, flow cytomtery and phosphorylation assays. The single-cell array module contains fluidic constrictions designed to trap and hold single host cells. Up to 100 single cells can be trapped and monitored for hours, enabling detailed statistically-significant measurements. The module was used to analyze translocation behavior of transcription factor NF-kB in macrophages upon activation

  3. Microscale Immune Studies Laboratory.

    Energy Technology Data Exchange (ETDEWEB)

    Poschet, Jens Fredrich; Carroll-Portillo, Amanda; Wu, Meiye; Manginell, Ronald Paul; Herr, Amy Elizabeth; Martino, Anthony A.; Perroud, Thomas D.; Branda, Catherine; Srivastava, Nimisha; Sinclair, Michael B.; Moorman, Matthew Wallace; Apblett, Christopher Alan; Sale, Kenneth L.; James, Conrad D.; Carles, Elizabeth L.; Lidke, Diane S. (University of New Mexico, Albuquerque, NM); Van Benthem, Mark Hilary; Rebeil, Roberto; Kaiser, Julie; Seaman, William (University of California, San Francisco, CA); Rempe, Susan; Brozik, Susan Marie; Jones, Howland D. T.; Gemperline, Paul (East Carolina University, Greenville, NC); Throckmorton, Daniel J.; Misra, Milind; Murton, Jaclyn K.; Carson, Bryan D.; Zhang, Zhaoduo; Plimpton, Steven James; Renzi, Ronald F.; Lane, Todd W.; Ndiaye-Dulac, Elsa; Singh, Anup K.; Haaland, David Michael; Faulon, Jean-Loup Michel; Davis, Ryan W.; Ricken, James Bryce; Branda, Steven S.; Patel, Kamlesh D.; Joo, Jaewook; Kubiak, Glenn D.; Brennan, James S.; Martin, Shawn Bryan; Brasier, Allan (University of Texas Mecial Branch, Galveston, TX)

    2009-01-01

    The overarching goal is to develop novel technologies to elucidate molecular mechanisms of the innate immune response in host cells to pathogens such as bacteria and viruses including the mechanisms used by pathogens to subvert/suppress/obfuscate the immune response to cause their harmful effects. Innate immunity is our first line of defense against a pathogenic bacteria or virus. A comprehensive 'system-level' understanding of innate immunity pathways such as toll-like receptor (TLR) pathways is the key to deciphering mechanisms of pathogenesis and can lead to improvements in early diagnosis or developing improved therapeutics. Current methods for studying signaling focus on measurements of a limited number of components in a pathway and hence, fail to provide a systems-level understanding. We have developed a systems biology approach to decipher TLR4 pathways in macrophage cell lines in response to exposure to pathogenic bacteria and their lipopolysaccharide (LPS). Our approach integrates biological reagents, a microfluidic cell handling and analysis platform, high-resolution imaging and computational modeling to provide spatially- and temporally-resolved measurement of TLR-network components. The Integrated microfluidic platform is capable of imaging single cells to obtain dynamic translocation data as well as high-throughput acquisition of quantitative protein expression and phosphorylation information of selected cell populations. The platform consists of multiple modules such as single-cell array, cell sorter, and phosphoflow chip to provide confocal imaging, cell sorting, flow cytomtery and phosphorylation assays. The single-cell array module contains fluidic constrictions designed to trap and hold single host cells. Up to 100 single cells can be trapped and monitored for hours, enabling detailed statistically-significant measurements. The module was used to analyze translocation behavior of transcription factor NF-kB in macrophages upon activation

  4. Relation between early life socioeconomic position and all cause mortality in two generations. A longitudinal study of Danish men born in 1953 and their parents

    DEFF Research Database (Denmark)

    Osler, Merete; Andersen, Anne-Marie Nybo; Batty, G David;

    2005-01-01

    OBJECTIVE: To examine (1) the relation between parental socioeconomic position and all cause mortality in two generations, (2) the relative importance of mother's educational status and father's occupational status on offspring mortality, and (3) the effect of factors in the family environment...... triads of father, mother, and offspring constituted of the cohort of men born in 1953, their parents, and grandparents. The educational status of mothers showed no independent effect on total mortality when father's occupational social class was included in the model in either of the triads. Low material...... wealth was the indicator that remained significantly associated with adult all cause mortality in a model also including parental social position and the intellectual climate of the family in 1968. In the men born in 1953 the influence of material wealth was strongest for deaths later in adult life...

  5. Does war contribute to family violence against children? Findings from a two-generational multi-informant study in Northern Uganda.

    Science.gov (United States)

    Saile, Regina; Ertl, Verena; Neuner, Frank; Catani, Claudia

    2014-01-01

    After 20 years of civil war in Northern Uganda, the continuity of violence within the family constitutes a major challenge to children's healthy development in the post-conflict era. Previous exposure to trauma and ongoing psychopathology in guardians potentially contribute to parental perpetration against children and dysfunctional interactions in the child's family ecology that increase children's risk of maltreatment. In order to investigate distal and proximal risk factors of child victimization, we first aimed to identify factors leading to more self-reported perpetration in guardians. Second, we examined factors in the child's family environment that promote child-reported experiences of maltreatment. Using a two-generational design we interviewed 368 children, 365 female guardians, and 304 male guardians from seven war-affected rural communities in Northern Uganda on the basis of standardized questionnaires. We found that the strongest predictors of self-reported aggressive parenting behaviors toward the child were guardians' own experiences of childhood maltreatment, followed by female guardians' victimization experiences in their intimate relationship and male guardians' posttrautmatic stress disorder (PTSD) symptoms and alcohol-related problems. Regarding children's self-report of victimization in the family, proximal factors including violence between adults in the household and male guardians' PTSD symptom severity level predicted higher levels of maltreatment. Distal variables such as female guardians' history of childhood victimization and female guardians' exposure to traumatic war events also increased children's report of maltreatment. The current findings suggest that in the context of organized violence, an intergenerational cycle of violence persists that is exacerbated by female guardians' re-victimization experiences and male guardians' psychopathological symptoms. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. New reactors for laboratory studies

    Energy Technology Data Exchange (ETDEWEB)

    Berty, J.M.

    1978-02-01

    Recent developments in design of laboratory and bench-scale reactors reflect mostly the developments in reaction engineering; that is the improved understanding of physical and chemical rate limiting processes, their interactions, and their effects on commercial-scale reactor performance. Whether a laboratory reactor is used to study the fundamentals of a commercial process or for pure scientific interest, it is important to know what physical or chemical process is limiting or influencing the rate and selectivity. To clarify this, a definition is required of the regime where physical influences exist, and study the intrinsic kinetics at conditions where physical processes do not affect the rate. Reactors are illustrated whose design was influenced by the above considerations. These reactors produce results which are independent of the reactors in which they were measured, and which can be scaled up with up-to-date reaction engineering techniques.

  7. BRCA1 gene variant p.P142H associated with male breast cancer: a two-generation genealogic study and literature review.

    Science.gov (United States)

    Spinelli, Claudio; Strambi, Silvia; Piccini, Lorenzo; Rossi, Leonardo; Aretini, Paolo; Caligo, Adelaide

    2015-12-01

    Breast cancer occurs rarely in male patient. BRCA1 gene mutation seems to be related to male breast cancer, but its role is not clearly defined. We have identified in a male patient affected by breast cancer the BRCA1 gene variant p.P142H. We performed a literature research using the keywords "male breast cancer", "male breast cancer mutations" and "BRCA" and we reviewed the cases. We found ew other studies regarding BRCA1 variant p.P142H, about female subjects. At the moment, BRCA1 gene variant p.P142H is not certainly classified as neutral or deleterious. Genetic testing for BRCA1 and BRCA2 and PALB2 mutation gene has been performed on our patient. Segregation analysis for this p.P142H BRCA1 variant has been extended to the second generation of the family. Genetic tests revealed a clear inheritance regarding the BRCA1 gene p. P142H variant. Of the eight patients with this specific genetic mutation, four presented breast cancer (bilateral in one case), two female and two male. None of the subjects in the family without the BRCA1 gene variant p. P142H presented breast cancer or other BRCA1 gene mutation-related cancers. Our analysis suggests that the BRCA1 gene variant p.P142H mutation is related with male breast cancer. Starting from these data, it can be inferred that more studies on MBC and its relation with the BRCA1 gene mutation P142H variant must be undertaken to improve prognostic and therapeutic strategies.

  8. Impact of prenatal and postnatal exposure to bisphenol A on female rats in a two generational study: Genotoxic and immunohistochemical implications

    Directory of Open Access Journals (Sweden)

    Gihan G. Moustafa

    2016-01-01

    Full Text Available Environmental xenoestrogen contaminant bisphenol A (BPA, widely used as a monomer in the manufacture of epoxy, polycarbonate plastics and polystyrene resins. However, exposure to BPA has raised concerns, and the negative impacts of its exposure on reproduction have been controversial. The purpose of this work was directed to assess the potential adverse effects of BPA on dam rats and their first generation females in a comparative toxicological study. Fifteen pregnant female rats were classified into three equal groups; first group was orally administered corn oil and served as control (group1, second and third groups were orally administered BPA at dose levels of 50 and 200 mg/kg b.wt respectively (groups 2 & 3. The administration was carried out daily from zero day through the gestation period (21 days until the last day of the lactation period (21days and was extended after weaning for three months, in which female off springs of first generation (F1 of the three groups of dams were classified into; F1control group (group 4, F1 group treated with low dose of BPA (group 5 and F1 group treated with high dose of BPA (group 6 which continued in daily oral administration of BPA at the same previously mentioned doses for three months. The results elucidated a clear marked DNA fragmentation in the ovary of both dam and F1 female groups especially at higher examined concentration. Also, the data demonstrated a significant increase in the serum levels of GGT, ALP, glucose, total cholesterol, triglycerides, LDH and also in the serum level of estrogen hormone. Meanwhile, our study recorded a significant decrease in total protein, catalase, GST, HDL and FSH hormone in both treated dam and F1 female groups which was more significantly decreased in F1 female rats. Moreover, our experiment illustrated up-regulation in the immunoexpression of ERβ in ovary, uterus and liver of dam and F1 female groups. The histopathological investigation showed

  9. Effects of benzophenone-3 exposure on endocrine disruption and reproduction of Japanese medaka (Oryzias latipes)—A two generation exposure study

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sujin; Jung, Dawoon [School of Public Health, Seoul National University, Seoul 151-742 (Korea, Republic of); Kho, Younglim [Department of Health, Environment and Safety, Eulji University, Seongnam 461-713 (Korea, Republic of); Choi, Kyungho, E-mail: kyungho@snu.ac.kr [School of Public Health, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2014-10-15

    Highlights: • Exposure to BP-3 led to adverse reproduction effects on Japanese medaka at 26 μg/L. • Changes in sex hormones and steroidogenic gene transcription were observed. • Parental exposure to BP-3 influenced on the growth of second generation fish. - Abstract: Benzophenone-3 (BP-3) has been widely used in sunscreens and cosmetics to protect human skin from the harmful effects of UV irradiation. While BP-3 has been frequently detected in surface waters, sediments and biota, only limited information is available on its in vivo toxicity, particularly in fish. In the present study the endocrine disrupting capacity of BP-3 and its underlying mechanisms were investigated using Japanese medaka (Oryzias latipes). Adult Japanese medaka pairs (F0) were exposed to 0, 4.7, 8.4, 26, or 90 μg/L (or 0, 15, 50, 150, or 500 μg/L of BP-3 based on nominal concentration) for 14 d and its effects on sex steroid hormones, and transcription of various associated genes were determined. Following additional 14 d of exposure, the F1 eggs reproduced were counted and were further exposed to 0, 5.4, 12, or 30 μg/L of BP-3 (or 0, 15, 50, or 150 μg/L based on nominal concentrations) until 30 d after hatching. Chemical analysis of the exposed media confirmed transformation of BP-3 to benzophenone-1 (BP-1), a more potent estrogen agonist. After 14 d of the adult fish exposure, plasma concentrations of testosterone (T) significantly increased in male fish. The 17β-estradiol (E2) to T (E2/T) ratio showed significant decreases in both male and female fish. Overall down-regulation of gonadal steroidogenic genes such as star, cyp11a, cyp17, hsd3b, hsd17b3, and cyp19a was also observed. After 28 d of exposure, the daily average egg reproduction per female was significantly reduced at 26 μg/L of BP-3. However, hatchability of F1 eggs was not affected by continuous exposure. After continued exposure until 30 dph, juvenile fish showed concentration-dependent decrease of condition factor

  10. Laboratories practice to transducers study

    Directory of Open Access Journals (Sweden)

    Kleber Romero Felizardo

    2004-01-01

    Full Text Available The objective of this work was to gather a collection of practical laboratory experiences , to discover the physical principles of different types of electrical transducers , and to compare them with theoretical models.

  11. Bodies in flowing plasmas - Laboratory studies

    Science.gov (United States)

    Stone, N. H.; Samir, U.

    1981-01-01

    A brief review of early rudimentary laboratory studies of bodies in flowing, rarefied plasmas is presented (e.g., Birkeland, 1908), along with a discussion of more recent parametric studies conducted in steady plasma wind tunnels, which includes the study by Hall et al. (1964), in which a strong ion density enhancement in the center of the ion void created downstream from the body was observed. Good agreement was found between the experimental results and theoretical calculations which omit ion thermal motion. Examples in which in situ data on the interaction between satellites and the ionospheric plasma have been elucidated by the laboratory results are presented, and include evidence for a midwake axial ion peak, and ion current density in the near-wake region. The application of the ionospheric laboratory to basic space plasma physics is discussed, and its application to some types of solar system plasma phenomena is illustrated.

  12. VDTs: Field levels, epidemiology, and laboratory studies

    Energy Technology Data Exchange (ETDEWEB)

    Kavet, R.; Tell, R.A. (Richard Tell Associates, Inc., Las Vegas, NV (USA))

    1991-07-01

    As the use of video display terminals (VDTs) has expanded, questions have been raised as to whether working at a VDT affects the risk of adverse pregnancy outcome. A particular focus for these questions has been the very low frequency (VLF) magnetic field produced by a VDT's horizontal deflection coil. VDTs also produce VLF electric fields, extremely low frequency (ELF) electric and magnetic fields, and static electric fields, Ten studies of pregnancy outcome in VDT operators have been conducted in six countries, and with one exception, none has concluded that magnetic fields from VDTs may predispose pregnant operators to spontaneous abortion or congenital malformation. The epidemiologic studies conducted thus far do not provide a basis for concluding that VDT work and adverse pregnancy outcome are associated. Studies of fetal resorptions and malformations in rodents exposed to VLF magnetic fields have produced inconsistent findings. Two laboratories in Sweden that studied mice have reported positive results, one laboratory showing field-related malformations (but not resorptions) and the other showing field-related resorptions (but not malformations). Two Canadian laboratories have reported negative results in rats and mice. Studies of avian embryos have also yielded inconsistent results, but lacking a maternal-fetal placental interface, avian embryos are a questionable model for evaluating human reproductive risks. Finally, VLF electric and magnetic fields measured at the operator position are in compliance with field strength standards and guidelines that have been established around the world. 55 refs.

  13. Two Generations of Path Dependence in Economics?

    DEFF Research Database (Denmark)

    Madsen, Mogens Ove

    2010-01-01

    Even if there is no fully articulated and generally accepted theory of Path Dependence it has eagerly been taken up across a wide range of social sciences – primarily coming from economics. Path Dependence is most of all a metaphor that offers reason to believe, that some political, social...... or economic processes have multiple possible paths of outcomes, rather than a unique path of equilibria. The selection among outcomes may depend on contingent choices or events – outcomes of path-dependent processes require a very relevant study – a perception of history....

  14. Laboratory studies in ultraviolet solar physics

    Science.gov (United States)

    Parkinson, W. H.; Kohl, J. L.; Gardner, L. D.; Raymond, J. C.; Smith, P. L.

    1991-01-01

    The research activity comprised the measurement of basic atomic processes and parameters which relate directly to the interpretation of solar ultraviolet observations and to the development of comprehensive models of the component structures of the solar atmosphere. The research was specifically directed towards providing the relevant atomic data needed to perform and to improve solar diagnostic techniques which probe active and quiet portions of the solar chromosphere, the transition zone, the inner corona, and the solar wind acceleration regions of the extended corona. The accuracy with which the physical conditions in these structures can be determined depends directly on the accuracy and completeness of the atomic and molecular data. These laboratory data are used to support the analysis programs of past and current solar observations (e.g., the Orbiting solar Observatories, the Solar Maximum Mission, the Skylab Apollo Telescope Mount, and the Naval Research Laboratory's rocket-borne High Resolution Telescope and Spectrograph). In addition, we attempted to anticipate the needs of future space-borne solar studies such as from the joint ESA/NASA Solar and Heliospheric Observatory (SOHO) spacecraft. Our laboratory activities stressed two categories of study: (1) the measurement of absolute rate coefficients for dielectronic recombination and electron impact excitation; and (2) the measurement of atomic transition probabilities for solar density diagnostics. A brief summary of the research activity is provided.

  15. Mental Health and Hmong Americans: A comparison of two generations

    Directory of Open Access Journals (Sweden)

    Pa Der Vang

    2014-12-01

    Full Text Available Early studies of Hmong refugees in the U.S. indicated high rates of mental distress related to post-migration stressors such as grief and loss, poverty, and social adversity. This study explores the mental health status of two generations of Hmong Americans 38 years after their first migration. The relationship between acculturation and mental health of 191 1st and 2nd generation Hmong are reported. Results indicated relatively low reports of depressive symptoms and medium to high rates of acculturation to American society. The results are unrelated to demographic factors indicating resilience and adaptation to Western society despite age and generational status and maintenance of culture of origin

  16. Zero-gravity cloud physics laboratory: Experiment program definition and preliminary laboratory concept studies

    Science.gov (United States)

    Eaton, L. R.; Greco, E. V.

    1973-01-01

    The experiment program definition and preliminary laboratory concept studies on the zero G cloud physics laboratory are reported. This program involves the definition and development of an atmospheric cloud physics laboratory and the selection and delineations of a set of candidate experiments that must utilize the unique environment of zero gravity or near zero gravity.

  17. Laboratory Studies Of Circumstellar Carbonaceous Grain Formation

    Science.gov (United States)

    Contreras, Cesar; Sciamma-O'Brien, Ella; Salama, Farid

    2014-06-01

    The study of the formation processes of dust is essential to understand the budget of extraterrestrial organic molecules. Although dust with all its components plays an important role in the evolution of interstellar (IS) chemistry and in the formation of organic molecules, little is known on the formation processes of carbonaceous dust. We report the progress that was recently achieved in this domain using NASA Ames’ COSmIC facility (Contreras & Salama 2013, ApJS, 208, 6). PAHs are important chemical building blocks of IS dust. They are detected in IDPs and in meteoritic samples. Additionally, observational, laboratory, and theoretical studies have shown that PAHs are an important, ubiquitous component of the ISM. The formation of PAHs from smaller molecules has not been extensively studied. Therefore, we have performed laboratory experiments to study the dynamic processes of carbon grain formation, starting from the smallest hydrocarbon molecules into the formation of larger PAH and further into nanograins. Studies of IS dust analogs formed from a variety of PAH and hydrocarbon precursors as well as species that include the atoms O, N, and S, have recently been performed in our laboratory using the COSmIC facility to provide conditions that simulate IS and circumstellar environments. The species formed in the COSmiC chamber through a pulsed discharge nozzle plasma source are detected and characterized with a cavity ringdown spectrometer coupled to a time-of-flight mass spectrometer, thus providing both spectroscopic and ion mass information in-situ. Analysis of solid soot particles was also conducted using scanning electron microscopy at the UCSC/NASA Ames’ MACS facility. The SEM analysis of the deposition of soot from methane and acetylene precursors seeded in argon plasmas provide examples on the types of nanoparticles and micrograins that are produced in these gas mixtures under our experimental conditions. From these measurements, we derive information on

  18. Laboratory study of volcanic ash electrification

    Science.gov (United States)

    Alois, Stefano; Merrison, Jonathan

    2016-04-01

    Electrostatic forces play an important role in the dynamics of volcanic plumes, for example in ash dispersion and aggregation phenomena. Field measurements of ash electrification are often technically challenging due to poor access and there lacks an accepted physical theory to describe the electrical charge exchange which occurs during particle contact. The goal of the study is to investigate single particle electrification under controlled conditions using advanced laboratory facilities. A novel technique is presented, based on the use of a laser based velocimeter. Here an electric field is applied and the field-induced drift velocity of (micron-sized) ash grains is measured as well as the particles fall velocity. This allows the simultaneous determination of a suspended grains size and electrical charge. The experiments are performed in a unique environmental wind tunnel facility under controlled low-pressure conditions. Preliminary results of particle electrification will be presented.

  19. A laboratory study of breaking waves

    Directory of Open Access Journals (Sweden)

    Jaros³aw Têgowski

    2004-09-01

    Full Text Available This paper deals with some aspects of the wave-breaking phenomenon. The objectives were to study wave-breaking criteria, and the probability of whitecap coverage under fully controlled wave conditions. An additional task was to in vestigate the characteristic spectral features of the noise produced by breaking waves and the acoustic energy generated during wave breaking events. A controlled experiment was carried out in the Ocean Basin Laboratory at MARINTEK, Trondheim (Norway. Waves were generated by a computer-controlled multi-flap wave maker, which reproduced a realistic pattern of the sea surface for the prescribed spectra. Using wave staff recordings and photographic techniques, correlations between the breaking parameters and the radiated acoustic emissions were established.

  20. Clinico-laboratory study on filarial lymphoedema

    Directory of Open Access Journals (Sweden)

    Mohamad A Ebrahim

    2012-01-01

    Full Text Available Context: Lymphatic filariasis is considered the second leading cause of permanent physical disability in humans next to mood disorder. Aims: To evaluate filarial lymphoedema as a considerable burden to patients and the community. Settings and Design: This study was conducted on 45 patients with filarial lymphoedema among 2,350 patients with lower limb edema and 22 age- and sex-matched controls, from May 2005 to May 2008. Materials and Methods: Subjects were subjected to full history taking, clinical examination, Doppler ultrasound on the affected leg, laboratory tests for filariasis. Statistical Analysis: Data were analyzed using the Statistical Package for Social Scientist (SPSS for windows 7.5. (SPSS Inc, Chicago, USA. Results: Male to female ratio was approximately 1:1.8. The age group 21-30 years was more affected (42%. The majority of cases of filarial lymphoedema in the present study were diagnosed in advanced irreversible stages. Five patients had hydrocele. Four cases (8.9% were detected to be microfilaremic, 60% of cases were positive for Immunoglobulin (Ig G, 4.44% were IgM positive and positive cases for filarial antigenemia were 64.4%. Conclusion: The majority of cases in the present study were detected in advanced irreversible stages with patient disability and serious socioeconomic impact.

  1. Rocket and Laboratory Studies in Astronomy

    Science.gov (United States)

    Feldman, Paul D.

    2001-01-01

    This is the final report for NASA Grant NAG5-5122 and covers the period from March 1, 1997 to February 28, 2001. This grant was a continuation of a program in rocket and laboratory studies in ultraviolet astronomy that was supported by NASA grant NAG5-619. As of March 1, 2001, this program is continuing under grant NAG5-5315. During the period of the grant, annual status reports have been submitted detailing the scientific achievements and current objectives of each report period. These will not be repeated here. Among the highlights of the program are four successful rocket launches including participation in the campaign to study comet Hale-Bopp in April 1997. We have continued our emphasis on long-slit spectroscopy of extended sources in the shorter wavelength far-ultraviolet, necessitating the development of evacuated telescope/spectrograph payloads. Finally, we also note the use of our ultraviolet calibration facilities in support of other sounding rocket investigators and for other space missions such as the Far Ultraviolet Spectroscopic Explorer. We include a list of the sounding rocket launches performed under NASA sponsorship during this period, a list of Ph.D. degrees awarded to students who worked in this program, and a summary bibliography of publications between 1997 and 2001.

  2. Malaria Laboratory Diagnostic Performance: Case studies of two ...

    African Journals Online (AJOL)

    Malaria Laboratory Diagnostic Performance: Case studies of two ... laboratory for malaria test. ... affected by high humidity and provide no quantification of parasite density (World Health ... Zomba District Health Office reports not less than 250.

  3. A Study of Mathematics Needed for Dental Laboratory Technology, Medical Laboratory Technology, and Respiratory Therapy.

    Science.gov (United States)

    Roberts, Keith J.

    A study was conducted to determine what mathematics skills were needed for Dental Laboratory Technology, Medical Laboratory Technology, and Respiratory Therapy. Data obtained from studies, course outlines, textbooks, and reports were used to construct a 79-item mathematics skill questionnaire. This questionnaire was administered to employers,…

  4. A laboratory study of floating lenticular anticyclones

    Science.gov (United States)

    Le Gal, Patrice; de La Rosa, Hector; Cros, Anne; Cruz-Gomez, Raúl; Le Bars, Michael

    2014-11-01

    Oceanic vortices play an important role in the redistribution of heat, salt and momentum in the oceans. Among these vortices, floating lenses or rings are often met in the meanders of warm currents. For instance the North Brazil Current rings are among the most intense and large anticyclonic vortices on Earth. In order to better describe these vortices, we propose here a laboratory study of these floating anticyclonic lenses. A blob of fresh water is slowly injected near the surface of a rotating layer of homogeneous salted water. Because of the opposite effects of rotation that tends to generate columnar structures and density stratification that spreads light water on the surface, the vortices take a finite size three dimensionnal typical shape. Visualization and PIV measurements of the shape, aspect ratios and vorticity profiles are compared to analytical predictions that use first a simple solid body rotation model and then a more realistic isolated Gaussian vorticity field inside the anticyclones. This work was carried out within the framework of a bilateral cooperation between CNRS (France) and CONACYT (Mexico).

  5. Case Studies in Sustainability Used in an Introductory Laboratory Course to Enhance Laboratory Instruction

    Science.gov (United States)

    Luster-Teasley, Stephanie; Hargrove-Leak, Sirena; Gibson, Willietta; Leak, Roland

    2017-01-01

    This educational research seeks to develop novel laboratory modules by using Case Studies in the Science Teaching method to introduce sustainability and environmental engineering laboratory concepts to 21st century learners. The increased interest in "going green" has led to a surge in the number of engineering students studying…

  6. The DoD Laboratory Utilization Study

    Science.gov (United States)

    1975-04-28

    5. These were computed at $30K per person, which assumes for computation that all reductions would be a pro rata 7 mix of professionals and support...requested statistics and is forwarded in accordance with reference (a). JAMES H’ PROBUS D’:Oeotor of Navy LaboratoriOs (AotinZ) Copy to: ASN (R&D) tNI

  7. Laboratory studies of crystal growth in magma

    Science.gov (United States)

    Hammer, J. E.; Welsch, B. T.; First, E.; Shea, T.

    2012-12-01

    The proportions, compositions, and interrelationships among crystalline phases and glasses in volcanic rocks cryptically record pre-eruptive intensive conditions, the timing of changes in crystallization environment, and the devolatilization history of eruptive ascent. These parameters are recognized as important monitoring tools at active volcanoes and interpreting geologic events at prehistoric and remote eruptions, thus motivating our attempts to understand the information preserved in crystals through an experimental appoach. We are performing laboratory experiments in mafic, felsic, and intermediate composition magmas to study the mechanisms of crystal growth in thermochemical environments relevant to volcanic environments. We target features common to natural crystals in igneous rocks for our experimental studies of rapid crystal growth phenomena: (1) Surface curvature. Do curved interfaces and spongy cores represent evidence of dissolution (i.e., are they corrosion features), or do they record the transition from dendritic to polyhedral morphology? (2) Trapped melt inclusions. Do trapped liquids represent bulk (i.e., far-field) liquids, boundary layer liquids, or something intermediate, depending on individual species diffusivity? What sequence of crystal growth rates leads to preservation of sealed melt inclusions? (3) Subgrain boundaries. Natural phenocrysts commonly exhibit tabular subgrain regions distinguished by small angle lattice misorientations or "dislocation lamellae" and undulatory extinction. Might these crystal defects be produced as dendrites undergo ripening? (4) Clusters. Contacting clusters of polymineralic crystals are the building blocks of cumulates, and are ubiquitous features of mafic volcanic rocks. Are plagioclase and clinopyroxene aligned crystallographically, suggesting an epitaxial (surface energy) relationship? (5) Log-normal size distribution. What synthetic cooling histories produce "natural" distributions of crystal sizes, and

  8. Airborne and laboratory studies of interstellar PAHs

    Science.gov (United States)

    Allamandola, L. J.; Sandford, S. A.; Hudgins, D. M.; Witteborn, Fred C.

    1995-01-01

    A brief history of the observations which have led to the hypothesis that polycyclic aromatic hydrocarbons (PAH's) are the carriers of the widespread interstellar emission features near 3050, 1615, '1300' and 890 cm(exp -1) (3.29, 6.2, '7.7', and 11.2 mu m) is presented. The central role of airborne spectroscopy is stressed. The principal reason for the assignment to PAH's was the resemblance of the interstellar emission spectrum to the laboratory absorption spectra of PAH's and PAH-like materials. Since precious little information was available on the properties of PAH's in the forms that are thought to exist under interstellar conditions -isolated and ionized in the emission zones, with the smallest PAH's being dehydrogenated- there was a need for a spectral data base on PAH's taken in these states. Here, the relevant infrared spectroscopic properties of PAH's will be reviewed. These laboratory spectra show that relative band intensities are severely altered and that band frequencies shift. It is shown that these new data alleviate several of the spectroscopic criticisms previously leveled at the hypothesis.

  9. Two-generation reproduction study of erythritol in rats

    NARCIS (Netherlands)

    Waalkens-Berendsen, D.H.; Smits- Prooije, A.E. van; Wijnands, M.V.M.; Bär, A.

    1996-01-01

    Erythritol was fed at dietary concentrations of 0, 2.5, 5, or 10% to Crl:(WI) WU BR rats of both sexes through two successive generations (F0 and F1). Twenty-four rats of each sex were mated in each group. For each generation one litter was reared until the pups were 21 days old. In the 10%

  10. Two-generation reproduction study of erythritol in rats

    NARCIS (Netherlands)

    Waalkens-Berendsen, D.H.; Smits- Prooije, A.E. van; Wijnands, M.V.M.; Bär, A.

    1996-01-01

    Erythritol was fed at dietary concentrations of 0, 2.5, 5, or 10% to Crl:(WI) WU BR rats of both sexes through two successive generations (F0 and F1). Twenty-four rats of each sex were mated in each group. For each generation one litter was reared until the pups were 21 days old. In the 10% erythrit

  11. Leaching of wood ash - Laboratory and field studies; Lakning av vedaska - Laboratorie- och faeltstudier

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, Per-Erik

    2012-02-15

    High forest production leads to diminishing amounts of base cations and micro nutrients in forest soils. This is due to uptake in, and harvest of, the trees. Losses can be compensated for by spreading stabilized wood ash on the forest ground, which means recycling of base cations and micro nutrients. Chemical composition of wood ash can easily be described by standard methods in the laboratory. However, this does not include the process of leaching in nature, such as which components and leaching rate for different compounds. During field conditions several factors are added, which are not available in the laboratory. After almost 10 years in the forest soils there still remains large quantities of the original product. Only 10-30 % of the wood ash products and 5 % of the lime product has been leached. In the laboratory study the leached amount was slightly larger, at the most 35 % for wood ash and 20 % for lime. Both studies indicate long time for weathering of the products in forest soils. Slower leaching rate from pellets of wood ash compared to leaching rate from crushed wood ash in the laboratory study is not verified by the field study. This indicates limited possibilities to control rates of leaching in the environment

  12. Laboratory and Modeling Studies of Insect Swarms

    Science.gov (United States)

    2016-03-10

    control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. Yale University Office of Sponsored Projects 25 Science Park - 3rd Floor New Haven...Center for the Study of Ecological Perception and Action, Department of Psychology, University of Connecticut (October, 2014) (invited seminar

  13. Laboratory studies of ocean mixing by microorganisms

    Science.gov (United States)

    Martinez-Ortiz, Monica; Dabiri, John O.

    2011-11-01

    Ocean mixing plays a major role in nutrient and energy transport and is an important input to climate models. Recent studies suggest that the contribution of fluid transport by swimming microorganisms to ocean mixing may be of the same order of magnitude as winds and tides. An experimental setup has been designed in order to study the mixing efficiency of vertical migration of plankton. To this end, a stratified water column is created to model the ocean's density gradient. The vertical migration of Artemia Salina (brine shrimp) within the water column is controlled via luminescent signals on the top and bottom of the column. By fluorescently labelling portions of the water column, the stirring of the density gradient by the animals is visualized and quantified. Preliminary results show that the vertical movement of these organisms produces enhanced mixing relative to control cases in which only buoyancy forces and diffusion are present.

  14. Laboratory Information Management System (LIMS): A case study

    Science.gov (United States)

    Crandall, Karen S.; Auping, Judith V.; Megargle, Robert G.

    1987-01-01

    In the late 70's, a refurbishment of the analytical laboratories serving the Materials Division at NASA Lewis Research Center was undertaken. As part of the modernization efforts, a Laboratory Information Management System (LIMS) was to be included. Preliminary studies indicated a custom-designed system as the best choice in order to satisfy all of the requirements. A scaled down version of the original design has been in operation since 1984. The LIMS, a combination of computer hardware, provides the chemical characterization laboratory with an information data base, a report generator, a user interface, and networking capabilities. This paper is an account of the processes involved in designing and implementing that LIMS.

  15. The Essential Role for Laboratory Studies in Atmospheric Chemistry.

    Science.gov (United States)

    Burkholder, James B; Abbatt, Jonathan P D; Barnes, Ian; Roberts, James M; Melamed, Megan L; Ammann, Markus; Bertram, Allan K; Cappa, Christopher D; Carlton, Annmarie G; Carpenter, Lucy J; Crowley, John N; Dubowski, Yael; George, Christian; Heard, Dwayne E; Herrmann, Hartmut; Keutsch, Frank N; Kroll, Jesse H; McNeill, V Faye; Ng, Nga Lee; Nizkorodov, Sergey A; Orlando, John J; Percival, Carl J; Picquet-Varrault, Bénédicte; Rudich, Yinon; Seakins, Paul W; Surratt, Jason D; Tanimoto, Hiroshi; Thornton, Joel A; Tong, Zhu; Tyndall, Geoffrey S; Wahner, Andreas; Weschler, Charles J; Wilson, Kevin R; Ziemann, Paul J

    2017-03-07

    Laboratory studies of atmospheric chemistry characterize the nature of atmospherically relevant processes down to the molecular level, providing fundamental information used to assess how human activities drive environmental phenomena such as climate change, urban air pollution, ecosystem health, indoor air quality, and stratospheric ozone depletion. Laboratory studies have a central role in addressing the incomplete fundamental knowledge of atmospheric chemistry. This article highlights the evolving science needs for this community and emphasizes how our knowledge is far from complete, hindering our ability to predict the future state of our atmosphere and to respond to emerging global environmental change issues. Laboratory studies provide rich opportunities to expand our understanding of the atmosphere via collaborative research with the modeling and field measurement communities, and with neighboring disciplines.

  16. The Essential Role for Laboratory Studies in Atmospheric Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Burkholder, James B. [National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States); Abbatt, Jonathan P. D. [Univ. of Toronto, ON (Canada); Barnes, Ian [Univ. of Wuppertal (Germany); Roberts, James M. [National Oceanic and Atmospheric Administration (NOAA), Boulder, CO (United States); Melamed, Megan L. [Univ. of Colorado, Boulder, CO (United States); Ammann, Markus [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Bertram, Allan K. [Univ. of British Columbia, Vancouver, BC (Canada); Cappa, Christopher D. [Univ. of California, Davis, CA (United States); Carlton, Annmarie G. [Univ. of California, Irvine, CA (United States); Carpenter, Lucy J. [Univ. of York (United Kingdom); Crowley, John N. [Max Planck Inst. of Chemistry, Mainz (Germany); Dubowski, Yael [Technion-Israel Inst. of Tech., Haifa (Israel); George, Christian [Univ. of Lyon (France); Heard, Dwayne E. [Univ. of Leeds (United Kingdom); Herrmann, Hartmut [Leibniz Inst. for Tropospheric Research (ITR), Leipzig (Germany); Keutsch, Frank N. [Harvard Univ., Cambridge, MA (United States); Kroll, Jesse H. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); McNeill, V. Faye [Columbia Univ., New York, NY (United States); Ng, Nga Lee [Georgia Inst. of Technology, Atlanta, GA (United States); Nizkorodov, Sergey A. [Univ. of California, Irvine, CA (United States); Orlando, John J. [National Center for Atmospheric Research, Boulder, CO (United States); Percival, Carl J. [Univ. of Manchester (United Kingdom); Picquet-Varrault, Bénédicte [Inst. Pierre-Simon Laplace, Creteil (France); Rudich, Yinon [Weizmann Inst. of Science, Rehovot (Israel); Seakins, Paul W. [Univ. of Leeds (United Kingdom); Surratt, Jason D. [Univ. of North Carolina, Chapel Hill, NC (United States); Tanimoto, Hiroshi [National Inst. for Environmental Studies, Tsukuba (Japan); Thornton, Joel A. [Univ. of Washington, Seattle, WA (United States); Tong, Zhu [Peking Univ., Beijing (China); Tyndall, Geoffrey S. [National Center for Atmospheric Research, Boulder, CO (United States); Wahner, Andreas [Forschungszentrum Julich (Germany); Weschler, Charles J. [Rutgers Univ., Piscataway, NJ (United States); Wilson, Kevin R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ziemann, Paul J. [Univ. of Colorado, Boulder, CO (United States)

    2017-02-07

    Laboratory studies of atmospheric chemistry characterize the nature of atmospherically relevant processes down to the molecular level, providing fundamental information used to assess how human activities drive environmental phenomena such as climate change, urban air pollution, ecosystem health, indoor air quality, and stratospheric ozone depletion. Laboratory studies have a central role in addressing the incomplete fundamental knowledge of atmospheric chemistry. This paper highlights the evolving science needs for this community and emphasizes how our knowledge is far from complete, hindering our ability to predict the future state of our atmosphere and to respond to emerging global environmental change issues. Finally, laboratory studies provide rich opportunities to expand our understanding of the atmosphere via collaborative research with the modeling and field measurement communities, and with neighboring disciplines.

  17. Tracer Studies In A Laboratory Beach Subjected To Waves

    Science.gov (United States)

    This work investigated the washout of dissolved nutrients from beaches due to waves by conducting tracer studies in a laboratory beach facility. The effects of waves were studied in the case where the beach was subjected to the tide, and that in which no tidal action was present...

  18. Tracer Studies In A Laboratory Beach Subjected To Waves

    Science.gov (United States)

    This work investigated the washout of dissolved nutrients from beaches due to waves by conducting tracer studies in a laboratory beach facility. The effects of waves were studied in the case where the beach was subjected to the tide, and that in which no tidal action was present...

  19. Field Research Studying Whales in an Undergraduate Animal Behavior Laboratory

    Science.gov (United States)

    MacLaren, R. David; Schulte, Dianna; Kennedy, Jen

    2012-01-01

    This work describes a new field research laboratory in an undergraduate animal behavior course involving the study of whale behavior, ecology and conservation in partnership with a non-profit research organization--the Blue Ocean Society for Marine Conservation (BOS). The project involves two weeks of training and five weekend trips on whale watch…

  20. Hiero-Dermato-Glyphics: Laboratory Study of the Skin

    Science.gov (United States)

    Roark, Oakley F.

    1977-01-01

    Explains several laboratory exercises using the skin, including the mapping of receptors, counting of sweat glands, computation of total skin area, comparison of various animal skins, measurement of the palm triradius angle, and study of epidermal ridges (dermatoglyphics) in males and females. (CS)

  1. A Study on Knowledge, Attitude And Practice of Laboratory Safety Measures Among Paramedical Staff of Laboratory Services

    Directory of Open Access Journals (Sweden)

    Hansa M Goswami, Sumeeta T Soni, Sachin M Patel, Mitesh K Patel

    2011-01-01

    Full Text Available Purpose: A lot of accidents occur in the laboratory due to lack of proper knowledge regarding laboratory safety measures, indifferent attitude & improper implementation of safe laboratory practices. In view of this, the present study on knowledge, Attitude & Practice (KAP of laboratory safety measures was carried out among paramedical staff of laboratory services of tertiary care teaching hospital, western India. Method: This was a comparative study which used a standardized, structured self-administered questionnaire to survey knowledge, attitude and practice of paramedical staff. The KAP study enrolled 81 respondents. Results: Regarding knowledge- the majority knew the very important issues related with laboratory safety like Post Exposure Prophylaxis (96.55% & discarding of blood samples (93.10% etc. In regard to attitude towards the scientific process, all are very much aware about importance of protective devices (i.e. Wearing Gloves and Biomedical waste management. In regard to the practice in laboratory, the entire study subject group (100% replied “YES” in each question that shows the good quality work of the laboratory. Conclusion: The induction training on Laboratory safety is very important and motivating exercise for improving the laboratory safety measures.

  2. A Three-Year Feedback Study of a Remote Laboratory Used in Control Engineering Studies

    Science.gov (United States)

    Chevalier, Amélie; Copot, Cosmin; Ionescu, Clara; De Keyser, Robin

    2017-01-01

    This paper discusses the results of a feedback study for a remote laboratory used in the education of control engineering students. The goal is to show the effectiveness of the remote laboratory on examination results. To provide an overview, the two applications of the remote laboratory are addressed: 1) the Stewart platform, and 2) the quadruple…

  3. Maintaining plethodontid salamanders in the laboratory for regeneration studies.

    Science.gov (United States)

    Arenas, Claudia Marcela; Gómez-Molina, Andrea; Delgado, Jean Paul

    2015-01-01

    Limb regeneration studies have been extensively carried out in species of Ambystomatidae and Salamandridae families. So far limited research has been conducted in species belonging to the Plethodontidae family, where some of the species differs from other salamander families due to their direct development, thus absence of a larval life. Here, we describe a protocol to maintain the plethodontid salamanders of genus Bolitoglossa species under laboratory conditions to perform regeneration studies.

  4. Clinical Laboratory Stressors Used to Study Alcohol–Stress Relationships

    OpenAIRE

    Thomas, Suzanne; Bacon, Amy K.; Sinha, Rajita; Uhart, Magdalena; Adinoff, Bryon

    2012-01-01

    Understanding the biologic systems that underlie the relationship between stress and alcohol consumption may lead to better prevention efforts and more effective treatments for alcoholism. Clinical laboratory studies offer a unique opportunity to examine these relationships by using a controlled environment to study how an acute stressor affects alcohol drinking and alcohol craving, how individuals in recovery or those at risk for alcoholism may respond differently to stressors relative to co...

  5. Educational Objectives Of Different Laboratory Types: A Comparative Study

    National Research Council Canada - National Science Library

    A.S. Tolba; Yasser .H. Elawady

    2009-01-01

    Laboratory-based courses play a critical role in scientific education. Automation is changing the nature of the laboratories, and there is a long-running debate about the value of hands-on versus simulated and remote laboratories...

  6. Laboratory Experiments and Instrument Intercomparison Studies of Carbonaceous Aerosol Particles

    Energy Technology Data Exchange (ETDEWEB)

    Davidovits, Paul [Boston College, Chestnut Hill, MA (United States)

    2015-10-20

    Aerosols containing black carbon (and some specific types of organic particulate matter) directly absorb incoming light, heating the atmosphere. In addition, all aerosol particles backscatter solar light, leading to a net-cooling effect. Indirect effects involve hydrophilic aerosols, which serve as cloud condensation nuclei (CCN) that affect cloud cover and cloud stability, impacting both atmospheric radiation balance and precipitation patterns. At night, all clouds produce local warming, but overall clouds exert a net-cooling effect on the Earth. The effect of aerosol radiative forcing on climate may be as large as that of the greenhouse gases, but predominantly opposite in sign and much more uncertain. The uncertainties in the representation of aerosol interactions in climate models makes it problematic to use model projections to guide energy policy. The objective of our program is to reduce the uncertainties in the aerosol radiative forcing in the two areas highlighted in the ASR Science and Program Plan. That is, (1) addressing the direct effect by correlating particle chemistry and morphology with particle optical properties (i.e. absorption, scattering, extinction), and (2) addressing the indirect effect by correlating particle hygroscopicity and CCN activity with particle size, chemistry, and morphology. In this connection we are systematically studying particle formation, oxidation, and the effects of particle coating. The work is specifically focused on carbonaceous particles where the uncertainties in the climate relevant properties are the highest. The ongoing work consists of laboratory experiments and related instrument inter-comparison studies both coordinated with field and modeling studies, with the aim of providing reliable data to represent aerosol processes in climate models. The work is performed in the aerosol laboratory at Boston College. At the center of our laboratory setup are two main sources for the production of aerosol particles: (a

  7. Preferences for Learning and Skill Development at Work: Comparison of Two Generations

    Directory of Open Access Journals (Sweden)

    Mariya Karaivanova

    2014-09-01

    Full Text Available The changing economic conditions of the current dynamic and insecure labour market make learning a constant preoccupation of the workforce with view of meeting the growing qualification demands. These demands are likely to influence the work preferences of both young people now entering the labour market and older people with established career paths. Research findings suggest that the younger generation exhibits a stronger orientation towards learning and skill development as compared to the older generations. Moreover, studies show that the younger people are more ready to leave the organization when they have better learning opportunities elsewhere. The present study aims at establishing how preferences for learning and skill development in the workplace relate to a number of job and organizational characteristics. Particular focus is placed on the predictive capacity of perceived learning opportunities towards the tendency to leave the organization for either of the two generations. The study addresses work preferences of two generations in the Bulgarian labour market. To this aim, 121 respondents answered a 55-item questionnaire consisting of newly developed scales as well as scales based on or adopted from standardized instruments such as the Extended Delft Measurement Kit (Roe et al., 2000. Contrary to findings from previous research done in countries with different cultural and socio-economic background, the older people in our sample were more eager to learn and more ready to leave their organization in pursuit of better opportunities, as compared to the younger generation. Another noteworthy conclusion is that the preferences for learning and development form different patterns in each of the two age groups and are expressed in a different way for each of the two generations.

  8. Planetary Simulation Chambers bring Mars to laboratory studies

    Energy Technology Data Exchange (ETDEWEB)

    Mateo-Marti, E.

    2016-07-01

    Although space missions provide fundamental and unique knowledge for planetary exploration, they are always costly and extremely time-consuming. Due to the obvious technical and economical limitations of in-situ planetary exploration, laboratory simulations are among the most feasible research options for making advances in planetary exploration. Therefore, laboratory simulations of planetary environments are a necessary and complementary option to expensive space missions. Simulation chambers are economical, more versatile, and allow for a higher number of experiments than space missions. Laboratory-based facilities are able to mimic the conditions found in the atmospheres and on the surfaces of a majority of planetary objects. Number of relevant applications in Mars planetary exploration will be described in order to provide an understanding about the potential and flexibility of planetary simulation chambers systems: mainly, stability and presence of certain minerals on Mars surface; and microorganisms potential habitability under planetary environmental conditions would be studied. Therefore, simulation chambers will be a promising tools and necessary platform to design future planetary space mission and to validate in-situ measurements from orbital or rover observations. (Author)

  9. Laboratories for the 21st Century: Case Studies; National Renewable Energy Laboratory, Science and Technology Facility, Golden, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    2007-03-01

    This publication is one in series of case studies for "Laboratories for the 21st Century," a joint program of the U.S. Environmental Protection Agency and the U.S. Department of Energy Federal Energy Management Program. It is intended for those who plan to design and construct public and private-sector laboratory buildings. This case study describes the Science and Technology Facility, a new laboratory at NREL that incorporated energy-efficient and sustainable design features including underfloor air distribution in offices, daylighting, and process cooling.

  10. Laboratory Study of Dispersion of Buoyant Surface Plumes

    DEFF Research Database (Denmark)

    Petersen, Ole; Larsen, Torben

    1990-01-01

    A laboratory a study on surface dispersion of buoyant plumes in open channel turbulence in made, where the buoyancy is due to both salinity and heat. The measured parameters are the downstream derivative of a plume width and height, which are integral-characteristics of the distributions of density......-differences. Other methods as infra-red sensing are used for visualizing purpose. The results are used to calibrate an integral model of the dispersion. Conclusions are that the dispersion of a buoyant surface plume can be treated the superposition of a buoyancy induced stretching and turbulent diffusion, reduced...

  11. Laboratory studies on electrical effects during volcanic eruptions

    Directory of Open Access Journals (Sweden)

    R. Büttner

    1999-06-01

    Full Text Available This laboratory study reports on electrical phenomena during the explosive eruption of a basaltoid silicate melt. Contact electricity is produced in the phase of thermo-hydraulic fracturing of magma during the explosive interaction with water. The electrical charge produced is directly proportional to the force of the explosion, as the force of explosion is linearly proportional to the surface generated by the thermo-hydraulic fracturing. Simulation of the ejection history using inerted gas as a driving medium under otherwise constant conditions did not result in significant electric charging. The results have the potential to explain in nature observed lightening in eruption clouds of explosive volcanic events.

  12. Segregation of an X ring chromosome in two generations.

    Science.gov (United States)

    Dallapiccola, B; Bruni, L; Boscherini, B; Pasquino, A M; Chessa, L; Vignetti, P

    1980-01-01

    A 45,X/46,X,r(X) mosaicism was found in a mother and daughter. Characterisation of the ring by banding studies showed that breakpoints had occurred at bands Xp13 and Xq27. It is confirmed that women heterozygotes for partial deficiencies of the short arm of an X chromosome are fertile. Although the mother developed secondary amenorrhoea at the age of 29, it is suggested that fertility per se may not be affected by deficiencies of the distal part of Xq. Images PMID:7205906

  13. [External quality assessment in clinical biochemistry laboratories: pilot study in 11 laboratories of Lomé (Togo)].

    Science.gov (United States)

    Kouassi, Kafui; Fétéké, Lochina; Assignon, Selom; Dorkenoo, Ameyo; Napo-Koura, Gado

    2015-01-01

    This study aims to evaluate the performance of a few biochemistry analysis and make recommendations to the place of the stakeholders. It is a cross-sectional study conducted between the October 1(st), 2012 and the July 31, 2013 bearing on the results of 5 common examinations of clinical biochemistry, provided by 11 laboratories volunteers opening in the public and private sectors. These laboratories have analysed during the 3 cycles, 2 levels (medium and high) of serum concentration of urea, glucose, creatinine and serum aminotransferases. The performance of laboratories have been determined from the acceptable limits corresponding to the limits of total errors, defined by the French Society of Clinical Biology (SFBC). A system of internal quality control is implemented by all laboratories and 45% of them participated in international programs of external quality assessment (EQA). The rate of acceptable results for the entire study was of 69%. There was a significant difference (p<0.002) between the performance of the group of laboratories engaged in a quality approach and the group with default implementation of the quality approach. Also a significant difference was observed between the laboratories of the central level and those of the peripheral level of our health system (p<0.047). The performance of the results provided by the laboratories remains relatively unsatisfactory. It is important that the Ministry of Health put in place a national program of EQA with mandatory participation.

  14. Study of the work of laboratory-scale oxidation ditch

    Directory of Open Access Journals (Sweden)

    Gogina Elena Sergeevna

    Full Text Available The social and economic development of the society to a greater or lesser degree touches upon ecological questions, which include water supply conservation. Waste water treatment plays a very important role. Over the recent years in developed countries the phenomenon of suburbanization has appeared. It means growth and development of the suburban area of the biggest cities. In relation with it, it seems perspective to investigate the technologies aimed at wastewater treatment coming from small settlements. The paper considers the prospects of the use of oxidation ditches as the main biological WWTP-structures for small towns in the Moscow region. In order to study the conditions to achieve high efficiency of nitrogen removal and to investigate the rule of simultaneous nitrification and denitrification removal (SND, the laboratory-scale oxidation ditch model was made in the Laboratory of Biological methods of Wastewater Treatment of Moscow State University of Civil Engineering. The experiment lasted for 6 months and showed good results, which can be used for further studies. The Michaelis - Menten formulas for enzyme kinetics of the studied biological system were obtained.

  15. Educational Objectives Of Different Laboratory Types: A Comparative Study

    OpenAIRE

    Tolba, A. S.; Elawady, Yasser . H.

    2009-01-01

    Laboratory-based courses play a critical role in scientific education. Automation is changing the nature of the laboratories, and there is a long-running debate about the value of hands-on versus simulated and remote laboratories. The remote lab technology has brought a significant improvement in communication within the Academic community and has improved students' learning experiences. There are different educational objectives as criteria for judging the laboratories: Hands-on advocates em...

  16. Laboratory-scale coal and char characterisation studies

    Energy Technology Data Exchange (ETDEWEB)

    Geli, J.; Milani, A.; Damiani, R.; Ferrari, M. [Centro Sviluppo Materiali S.p.A., Roma (Italy)

    1998-12-31

    A laboratory scale study on nine coals, aimed at correlating coal properties (basically determined by rank and maceral composition) with char morphotextural features and combustion behaviour, was carried out. Proximate, ultimate, technological and petrographic analyses on coals were effectuated, and a standard laboratory test, developed at CSM, was carried out in order to determine coal combustion efficiency (EC). The tested coals are resulted single coals and more or less complex blends. Chars were produced by coal pyrolysis in a Drop Tube Furnace (DTF) under nitrogen flow at 1600{degree}C and submitted to a chemical and technological characterization; besides, the morphotextures of char particles were investigated by a polarized optical microscope POM) and classified. Char combustion was carried out in air flow by DTF, too, at 1600{degree}C and the residual combustion particles were submitted to ultimate and petrographic analyses. Finally three coals of the studied series were pyrolysed and their chars burnt by DTF at 1200{degree}C in order to determine the influence of temperature on combustion properties. Results allowed to individuate the main characteristics of coals and chars with resect to the combustion behaviour, and the relationships among them; therefore they provide an evaluation rule for coal selection and a basis of a method for `building` the best blends for pulverized coal boiler. 18 refs., 6 figs., 22 tabs.

  17. Clinical laboratory stressors used to study alcohol-stress relationships.

    Science.gov (United States)

    Thomas, Suzanne; Bacon, Amy K; Sinha, Rajita; Uhart, Magdalena; Adinoff, Bryon

    2012-01-01

    Understanding the biologic systems that underlie the relationship between stress and alcohol consumption may lead to better prevention efforts and more effective treatments for alcoholism. Clinical laboratory studies offer a unique opportunity to examine these relationships by using a controlled environment to study how an acute stressor affects alcohol drinking and alcohol craving, how individuals in recovery or those at risk for alcoholism may respond differently to stressors relative to control subjects, and how alcohol differentially affects stress reactivity in these groups. This article reviews some of the most common physical, psychological, and pharmacological stressors used in stress-induction studies designed to reveal details about the relationship between stress reactivity and alcohol use and abuse.

  18. Laboratory study of nitrate photolysis in Antarctic snow

    DEFF Research Database (Denmark)

    Berhanu, Tesfaye A.; Meusinger, Carl; Erbland, Joseph;

    2014-01-01

    Atmospheric nitrate is preserved in Antarctic snow firn and ice. However, at low snow accumulation sites, post-depositional processes induced by sunlight obscure its interpretation. The goal of these studies (see also Paper I by Meusinger et al. [" Laboratory study of nitrate photolysis...... in Antarctic snow. I. Observed quantum yield, domain of photolysis, and secondary chemistry," J. Chem. Phys. 140, 244305 (2014)]) is to characterize nitrate photochemistry and improve the interpretation of the nitrate ice core record. Naturally occurring stable isotopes in nitrate (15N, 17O, and 18O) provide...... additional information concerning post-depositional processes. Here, we present results from studies of the wavelength-dependent isotope effects from photolysis of nitrate in a matrix of natural snow. Snow from Dome C, Antarctica was irradiated in selected wavelength regions using a Xe UV lamp and filters...

  19. Educational Objectives Of Different Laboratory Types: A Comparative Study

    CERN Document Server

    Elawady, Yasser H

    2009-01-01

    Laboratory based courses play a critical role in scientific education. Automation is changing the nature of the laboratories, and there is a long running debate about the value of hands on versus simulated and remote laboratories. The remote lab technology has brought a significant improvement in communication within the Academic community and has improved students learning experiences. There are different educational objectives as criteria for judging the laboratories: Hands on advocates emphasize design skills, while remote lab advocates focus on conceptual understanding. Remote laboratories offer all the advantages of the new technology, but are often a poor replacement for real laboratory work. Remote laboratories are similar to simulation techniques in that they require minimal space and time, because the experiments can be rapidly configured and run over the Internet [Web]. But unlike simulations, they provide real data. This paper presents a comparative analysis for the educational objectives of the th...

  20. Laboratory Studies of Vibrational Relaxation: Important Insights for Mesospheric OH

    Science.gov (United States)

    Kalogerakis, Konstantinos S.; Matsiev, Daniel

    2016-04-01

    The hydroxyl radical has a key role in the chemistry and energetics of the Earth's middle atmosphere. A detailed knowledge of the rate constants and relevant pathways for OH(high v) vibrational relaxation by atomic and molecular oxygen and their temperature dependence is absolutely critical for understanding mesospheric OH and extracting reliable chemical heating rates from atmospheric observations. We have developed laser-based experimental approaches to study the complex collisional energy transfer processes involving the OH radical and other relevant atmospheric species. Previous work in our laboratory indicated that the total removal rate constant for OH(v = 9) + O at room temperature is more than one order of magnitude larger than that for removal by O2. Thus, O atoms are expected to significantly influence the intensity and vibrational distribution extracted from the Meinel OH(v) emissions. We will report our most recent laboratory experiments that corroborate the aforementioned result for OH(v = 9) + O and provide important new insights on the mechanistic pathways involved. We will also highlight relevant atmospheric implications, including warranted revisions of current mesospheric OH models. Research supported by SRI International Internal R&D and NSF Aeronomy grant AGS-1441896. Previously supported by NASA Geospace Science grant NNX12AD09G.

  1. Design of laboratory experiments to study radiation-driven implosions

    Science.gov (United States)

    Keiter, P. A.; Trantham, M.; Malamud, G.; Klein, S. R.; Davis, J.; VanDervort, R.; Shvarts, D.; Drake, R. P.; Stone, J. M.; Fraenkel, M.; Frank, Y.; Raicher, E.

    2017-03-01

    The interstellar medium is heterogeneous with dense clouds amid an ambient medium. Radiation from young OB stars asymmetrically irradiate the dense clouds. Bertoldi (1989) developed analytic formulae to describe possible outcomes of these clouds when irradiated by hot, young stars. One of the critical parameters that determines the cloud's fate is the number of photon mean free paths in the cloud. For the extreme cases where the cloud size is either much greater than or much less than one mean free path, the radiation transport should be well understood. However, as one transitions between these limits, the radiation transport is much more complex and is a challenge to solve with many of the current radiation transport models implemented in codes. We present the design of laboratory experiments that use a thermal source of x-rays to asymmetrically irradiate a low-density plastic foam sphere. The experiment will vary the density and hence the number of mean free paths of the sphere to study the radiation transport in different regimes. We have developed dimensionless parameters to relate the laboratory experiment to the astrophysical system and we show that we can perform the experiment in the same transport regime.

  2. Feasibility study of medical isotope production at Sandia National Laboratories

    Energy Technology Data Exchange (ETDEWEB)

    Massey, C.D.; Miller, D.L.; Carson, S.D. [Sandia National Labs., Albuquerque, NM (United States). Environmental Regulatory Assessment Dept.] [and others

    1995-12-01

    In late 1994, Sandia National Laboratories in Albuquerque, New Mexico, (SNL/NM), was instructed by the Department of Energy (DOE) Isotope Production and Distribution Program (IPDP) to examine the feasibility of producing medically useful radioisotopes using the Annular Core Research Reactor (ACRR) and the Hot Cell Facility (HCF). Los Alamos National Laboratory (LANL) would be expected to supply the targets to be irradiated in the ACRR. The intent of DOE would be to provide a capability to satisfy the North American health care system demand for {sup 99}Mo, the parent of {sup 99m}Tc, in the event of an interruption in the current Canadian supply. {sup 99m}Tc is used in 70 to 80% of all nuclear medicine procedures in the US. The goal of the SNL/NM study effort is to determine the physical plant capability, infrastructure, and staffing necessary to meet the North American need for {sup 99}Mo and to identify and examine all issues with potential for environmental impact.

  3. Anterior chamber lenses. Part II: A laboratory study.

    Science.gov (United States)

    Apple, D J; Hansen, S O; Richards, S C; Ellis, G W; Kavka-Van Norman, D; Tetz, M R; Pfeffer, B R; Park, R B; Crandall, A S; Olson, R J

    1987-03-01

    An analysis of 606 surgically removed anterior chamber intraocular lens (IOL) specimens revealed that 351 or 58% of these were small-diameter, round loop, closed-loop styles. Because of the extremely high percentage of IOLs with this design received in our laboratory and the correlation of clinical histories with our histopathologic findings, we have concluded that such IOLs do not provide the safety and efficacy achieved by other anterior chamber lens designs. The finely polished, one-piece, all-PMMA styles fared well in our study. Although these one-piece styles comprise well over 50% of the American market share of anterior chamber IOLs, they comprise only 14% of all anterior chamber IOLs accessioned in our laboratory, compared to 58% for closed-loop designs. We believe that implantation of anterior chamber lenses with small-diameter, round, closed loops is no longer warranted. Patients in whom these IOLs have already been implanted should be carefully followed. It is our opinion that the FDA should recall or closely monitor all IOLs of this design and that implantation of closed-loop lenses should be discontinued in the United States. Furthermore, we believe that an IOL deemed to be not medically sound or worthy of implantation in the United States should not be marketed or donated outside of this country.

  4. Laboratory Studies of Ice Nucleation on Volcanic Ash

    Science.gov (United States)

    Tolbert, M. A.; Schill, G. P.; Genareau, K. D.

    2014-12-01

    Ice nucleation on volcanic ash controls both ash aggregation and cloud glaciation, which affect human respiratory health, atmospheric transport, and global climate. We have performed laboratory studies of the depositional and immersion freezing efficiency of three distinct samples of volcanic ash using Raman Microscopy coupled to an environmental cell. Ash from the Fuego (Basaltic Ash, Guatemala), Soufriere Hills (Andesetic Ash, Montserrat), and Taupo (Rhyolitic Ash, New Zealand) volcanoes were chosen to represent different geographical locations and silica content. All ash samples were quantitatively analyzed for both percent crystallinity and mineralogy using X-ray diffraction. We find that all three samples of volcanic ash are excellent depositional ice nuclei, nucleating ice at ice saturation ratios of 1.05 ± 0.1. For immersion freezing, however, only the Taupo ash exhibited efficient heterogeneous ice nucleation activity. Similar to recent studies on mineral dust, we suggest that the mineralogy of volcanic ash may dictate its ice nucleation activity in the immersion mode.

  5. Laboratory studies of briquetting and coking of hard brown coals

    Energy Technology Data Exchange (ETDEWEB)

    Wollenberg, R.; Basanshaw, B.

    1988-01-01

    Assesses feasibility of producing lumpy, high strength coke from hard brown coal unsuitable for conventional briquetting and coking technologies. Laboratory studies used brown coal with 11.5 to 23.5% ash content and 11.8 to 48% coal moisture from the Adun-tschulun, Scharin-gol, Baga-nur and Nalaich deposits in Mongolia. Two experimental briquetting technologies (briquetting of pregranulated coal dust, briquetting of dried coal from slurry comminution) were applied. Resulting briquets were coked at maximum 1,000 C temperature. Graphs provide briquetting and coking results. Influence of major briquetting and coking parameters is evaluated. The highest briquet compression strength obtained ranged between 15.2 and 34.3 MPa, the highest coke compression strength was 32.0 up to 87.0 MPa. Studies proved that suitable coke for use in the metallurgical and chemical industry can be produced from various types of hard brown coal. 6 refs.

  6. Rorschach measures of aggression: a laboratory-based validity study.

    Science.gov (United States)

    Kivisto, Aaron J; Swan, Scott A

    2013-01-01

    This study sought to complement the archival research designs that have established the empirical foundations of Rorschach aggression scores, including Exner's ( 2003 ) Aggressive Movement (AG) score and Meloy and Gacono's ( 1992 ) Aggressive Content (AgC), Aggressive Past (AgPast), and Aggressive Potential (AgPot) variables. Utilizing a highly controlled laboratory-based aggression paradigm and self-report measures of violence history in a sample of 35 undergraduate males with an average age of 19.38 (SD = 2.11), this study found that only AgC was positively associated with in vivo aggression (r = .40, p = .02). None of the Rorschach measures of aggression were significantly associated with self-reported violence history, although there were several trends approaching significance. Theoretical and methodological implications are discussed.

  7. Change in argonne national laboratory: a case study.

    Science.gov (United States)

    Mozley, A

    1971-10-01

    Despite traditional opposition to change within an institution and the known reluctance of an "old guard" to accept new managerial policies and techniques, the reactions suggested in this study go well beyond the level of a basic resistance to change. The response, indeed, drawn from a random sampling of Laboratory scientific and engineering personnel, comes close to what Philip Handler has recently described as a run on the scientific bank in a period of depression (1, p. 146). It appears that Argonne's apprehension stems less from the financial cuts that have reduced staff and diminished programs by an annual 10 percent across the last 3 fiscal years than from the administrative and conceptual changes that have stamped the institution since 1966. Administratively, the advent of the AUA has not forged a sense of collaborative effort implicit in the founding negotiations or contributed noticeably to increasing standards of excellence at Argonne. The AUA has, in fact, yet to exercise the constructive powers vested in them by the contract of reviewing and formulating long-term policy on the research and reactor side. Additionally, the University of Chicago, once the single operator, appears to have forfeited some of the trust and understanding that characterized the Laboratory's attitude to it in former years. In a period of complex and sensitive management the present directorate at Argonne is seriously dissociated from a responsible spectrum of opinion within the Laboratory. The crux of discontent among the creative scientific and engineering community appears to lie in a developed sense of being overadministered. In contrast to earlier periods, Argonne's professional staff feels a critical need for a voice in the formulation of Laboratory programs and policy. The Argonne senate could supply this mechanism. Slow to rally, their present concern springs from a firm conviction that the Laboratory is "withering on the vine." By contrast, the Laboratory director Powers

  8. Study on Laboratory Method for Refining of SR Diesel Fuel

    Institute of Scientific and Technical Information of China (English)

    Li Junling; Zheng Tinglu; Han Zhaping

    2006-01-01

    The method for refining the straight-run diesel fuel was studied in laboratory scale in order to make the acid number of diesel fraction comply with the standard while removing the naphthenic acids contained in diesel without causing environmental pollution. After comparing the effect of refining using three solvents, the isopropyl alcohol-HOA was specified as the best solvent. Meanwhile, the relationship between the acid number of diesel fraction and the amount of solvent used and the relationship between the concentration of solvent and temperature and the stability of diesel in terms of its acid number were also investigated. Experimental results had shown that when the mass fraction of the HOA-IPA solvent was 20% at a dosage of 17 mL of the solvent and a temperature of 30℃, the acid number of the refined diesel fraction was 0.015 mg KOH/g with a good stability of acidity in the diesel traction.

  9. Study of CSR Effects in the Jefferson Laboratory FEL Driver

    Energy Technology Data Exchange (ETDEWEB)

    Hall, C. C. [Colorado State U.; Biedron, S. [Colorado State U.; Burleson, Theodore A. [Colorado State U.; Milton, Stephen V. [Colorado State U.; Morin, Auralee L. [Colorado State U.; Benson, Stephen V. [JLAB; Douglas, David R. [JLAB; Evtushenko, Pavel E. [JLAB; Hannon, Fay E. [JLAB; Li, Rui [JLAB; Tennant, Christopher D. [JLAB; Zhang, Shukui [JLAB; Carlsten, Bruce E. [LANL; Lewellen, John W. [LANL

    2013-08-01

    In a recent experiment conducted on the Jefferson Laboratory IR FEL driver the effects of Coherent Synchrotron Radiation (CSR) on beam quality were studied. The primary goal of this work was to explore CSR output and effect on the beam with variation of the bunch compression in the IR chicane. This experiment also provides a valuable opportunity to benchmark existing CSR models in a system that may not be fully represented by a 1-D CSR model. Here we present results from this experiment and compare to initial simulations of CSR in the magnetic compression chicane of the machine. Finally, we touch upon the possibility for CSR induced microbunching gain in the magnetic compression chicane, and show that parameters in the machine are such that it should be thoroughly damped.

  10. Laboratory aging studies for the HERA-B muon chambers

    CERN Document Server

    Danilov, M; Titov, M; Zaitsev, Y

    2002-01-01

    The severe radiation environment of the HERA-B experiment leads to a maximum accumulated charge on a wire, within the muon detector, of 200 mC/cm wire. For operation in this high-intensity environment, the main criteria for the gas choice turned out to be stability against aging. We report recent results of laboratory aging studies performed by irradiating proportional wire chambers filled with Ar/CF sub 4 /CH sub 4 (74:20:6), Ar/CF sub 4 /CH sub 4 (67:30:3), and Ar/CF sub 4 /CO sub 2 (65:30:5) mixtures. The penetration of water and oxygen through the walls of plastic tubes has also been investigated. Water can be introduced indirect to the gas mixture by using polyamide (nylon) pipes for gas supply lines.

  11. Design of Laboratory Experiments to Study Photoionization Fronts

    Science.gov (United States)

    Gray, William James; Davis, Josh; Drake, R. Paul

    2017-06-01

    Here we present the theoretical foundation for a laboratory experiment to study photoionization fronts. Photoionization fronts play important roles in the formation and evolution of structure in the Universe. A properly designed experiment will have to control the recombination rate, electron impact ionization rate, and the initial thermal spectrum. We show that such an experiment can be designed, but requires the use of the largest high-energy-density laser facilities, such as Omega, Z, and NIF. We also show that prior experiments do not actually generate photoionization fronts, rather a heat front is produced by heat conductions. We show some initial simulation results of the current experimental design and characterize the ionization front.

  12. Studies of Ionospheric Processes in the Atmosphere and the Laboratory

    Science.gov (United States)

    2006-06-01

    relevance to HAARP observations, and on vibrationally-excited levels of the O2 ground state [2] and the b1Σ +g excited state [3]. Synergy with the...UT [20] 29.4 (33) 260 0.94 .077 3/24/95 1737 UT 43.4 (44) 278 0.54 0.53 HAARP 62N, 145W 3/20/04 0617 UT [21] 54 (44) 290 0.33 0.54... HAARP 0.62 5.0E8 1.09E8 4.6 Studies of Ionospheric Processes in the Atmosphere and the Laboratory RTO-MP-IST-056 1 - 9 UNCLASSIFIED/UNLIMITED

  13. Partnering at the National Laboratories: Catalysis as a Case Study

    Energy Technology Data Exchange (ETDEWEB)

    JACKSON,NANCY B.

    1999-09-14

    The role of the national laboratories, particularly the defense program laboratories, since the end of the cold war, has been a topic of continuing debate. The relationship of national laboratories to industry spurred debate which ranged from designating the labs as instrumental to maintaining U.S. economic competitiveness to concern over the perception of corporate welfare to questions regarding the industrial globalization and the possibility of U.S. taxpayer dollars supporting foreign entities. Less debated, but equally important, has been the national laboratories' potential competition with academia for federal research dollars and discussions detailing the role of each in the national research enterprise.

  14. Laboratory Studies of Methane and Its Relationship to Prebiotic Chemistry

    Science.gov (United States)

    Kobayashi, Kensei; Geppert, Wolf D.; Carrasco, Nathalie; Holm, Nils G.; Mousis, Olivier; Palumbo, Maria Elisabetta; Waite, J. Hunter; Watanabe, Naoki; Ziurys, Lucy M.

    2017-08-01

    To examine how prebiotic chemical evolution took place on Earth prior to the emergence of life, laboratory experiments have been conducted since the 1950s. Methane has been one of the key molecules in these investigations. In earlier studies, strongly reducing gas mixtures containing methane and ammonia were used to simulate possible reactions in the primitive atmosphere of Earth, producing amino acids and other organic compounds. Since Earth's early atmosphere is now considered to be less reducing, the contribution of extraterrestrial organics to chemical evolution has taken on an important role. Such organic molecules may have come from molecular clouds and regions of star formation that created protoplanetary disks, planets, asteroids, and comets. The interstellar origin of organics has been examined both experimentally and theoretically, including laboratory investigations that simulate interstellar molecular reactions. Endogenous and exogenous organics could also have been supplied to the primitive ocean, making submarine hydrothermal systems plausible sites of the generation of life. Experiments that simulate such hydrothermal systems where methane played an important role have consequently been conducted. Processes that occur in other Solar System bodies offer clues to the prebiotic chemistry of Earth. Titan and other icy bodies, where methane plays significant roles, are especially good targets. In the case of Titan, methane is both in the atmosphere and in liquidospheres that are composed of methane and other hydrocarbons, and these have been studied in simulation experiments. Here, we review the wide range of experimental work in which these various terrestrial and extraterrestrial environments have been modeled, and we examine the possible role of methane in chemical evolution.

  15. Tonsillitis in children: unnecessary laboratory studies and antibiotic use.

    Science.gov (United States)

    Kunnamo, Antti; Korppi, Matti; Helminen, Merja

    2016-02-01

    The Finnish Current Care Guidelines on diagnostics and treatment of sore throat recommend the treatment of only group A streptococcus (GAS) positive cases with penicillin. The aim of the study was to evaluate how these guidelines are followed in the pediatric emergency unit. We analyzed retrospectively the data on microbiological studies and blood tests done, and data on prescribing of antibiotics, of 200 children admitted for febrile exudative tonsillitis. After the clinical diagnosis of exudative tonsillitis, antigen test and/or culture for GAS identification was done in >95% of cases. All the 32 (16%) children with GAS infection, but also 52 (38%) of the 137 children without any evidence of bacterial infection received antibiotics. Additional laboratory studies were done in 96% of children. Serum C-reactive concentrations or white blood cell counts were not able to separate streptococcal from non-streptococcal tonsillitis. No serious bacterial infection was diagnosed. The Finnish Current Care Guidelines lead to over-treatment with antibiotics. None of the 200 children returned after discharge, suggesting that undertreatment did not happen.

  16. ELF electric and magnetic fields: Pacific Northwest Laboratory studies

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, L.E.

    1992-06-01

    Studies have been conducted at Battelle, Pacific Northwest Laboratory, to examine extremely-low-frequency (ELF) electromagnetic fields for possible biological effects in animals. Three areas of investigation are reported here: (1) studies on the nervous system, including behavior and neuroendocrine function, (2) experiments on cancer development in animals, and (3) measurements of currents and electric fields induced in animal models by exposure to external magnetic fields. In behavioral experiments, rats have been shown to be responsive to ELF electric field exposure. Furthermore, experimental data indicate that short-term memory may be affected in albino rats exposed to combined ELF and static magnetic fields. Neuroendocrine studies have been conducted to demonstrate an apparent stress-related response in rats exposed to 60-Hz electric fields. Nighttime pineal melatonin levels have been shown to be significantly depressed in animals exposed to either electric or magnetic fields. A number of animal tumor models are currently under investigation to examine possible relationships between ELF exposure and carcinogenesis. Finally, theoretical and experimental measurements have been performed which form the basis for animals and human exposure comparisons.

  17. Who are Sleeping in Sleep Laboratory? A Retrospective Study

    Directory of Open Access Journals (Sweden)

    Mine Ayşe Altun Emirza

    2012-03-01

    Full Text Available OBJECTIVE: Aim of this study is to compare the results of gold standard in diagnosing sleep disorders polysomnography (PSG with the physician’s preliminary diagnosis and complaints of patients in our data of sleep laboratory. METHODS: 656 patients who made PSG were included in the study. All of the patients age, gender, comorbid chronic disease, complaints, preliminary diagnosis and PSG diagnosis were evaluated retrospectively. RESULTS: In our study, the average age of patients was 56 and 43% women 57% were male. Complaints of patients were snoring, fatigue, stopped breath during sleep, insomnia, headache, daytime sleepiness, restless legs and abnormal behaviors during sleep. According to preliminary diagnoses and PSG diagnoses; Obstructive Sleep Apnea Syndrome (OSAS, narcolepsy, REM behavior disorder (RBD reduced (p 0.05. Sleep disorders in patients was accompanied by chronic diseases, hypertension (34.3%, diabetes (12.8%, Chronic Obstructive Pulmonary Disease (COPD (1.2%, epilepsy (1.8%, Parkinson's disease (3.5%, dementia (3.2%, depression (18.4%, cardiovascular disease (13.3% and cerebrovascular disease (4.9%. 9%. CONCLUSION: We are offering a good clinical history and physical examination with the correct interpretation of PSG for the differential diagnosis can be made true, accurate diagnoses and appropriate treatment modalities in our patients.

  18. Molecular Carbon in the Galaxy: Laboratory and Observational Studies

    Science.gov (United States)

    Saykally, Richard James

    2003-01-01

    In a collaboration with the Mats Larsson group from Stockholm, we carried out a new measurement of the rate of dissociative recombination of H(sup *, sub j), using a new pulsed supersonic beam source of rotationally cold H(sup *, sub j). This source was first designed and characterized in our lab by IR cavity ringdown spectroscopy, determining a rotationaYtranslationa1 temperature of 20-60K, depending on conditions. This new source was then taken to Stockholm for the recombination rate studies at the CRYRING storage ring. The recombination rate constant measured against temperature yields values consistent with the most recent calculations, whereas previous experimental measurements varied over a range of 10(exp 4) and were poor agreement with theory. This is a crucial achievement for understanding the ion chemistry of diffuse clouds. Moreover, this result in combination with recent observations implies a greatly enhanced (factor of 40) cosmic ray ionization rate in a diffuse cloud (zeta Persei) relative to previous studies. The implications of this are discussed in our recent Nature paper. An enhanced cosmic-ray flux towards zeta Persei inferred from a laboratory study of the H(sup *, sub j)-e(sup -) recombination rate.

  19. Laboratory studies and Pompe disease: from suspicion to therapy monitoring

    Directory of Open Access Journals (Sweden)

    K. V. Savost’yanov

    2016-01-01

    Full Text Available Pompe disease (PD is a rare, progressive, commonly fatal inherited autosomal recessive disease that is difficult to diagnose due to its obvious clinical heterogeneity and low awareness among physicians. Access to the laboratory diagnosis of rare diseases increases every year. In the past several years, Russian and foreign laboratories have achieved considerable success in accelerating and improving the diagnostic accuracy of PD. Unfortunately, the Russian-language literature contains scarce relevant information on the laboratory diagnosis of PD. This review is to fill up this gap. 

  20. The development of virtual laboratories: a case study

    Science.gov (United States)

    Wang, Haiyun; Pan, Xinmin

    2004-03-01

    At first, this paper introduces some features about Virtual Reality, which includes concept, practical use, basic character, etc. Then it turns to one of its branch-Virtual Laboratories. Virtual Laboratories developed rapidly in recent years, and it will have great effect on education area. This paper mentions about many advantages compared with traditional laboratories, the supporting technique, practical significance, etc. Later this paper mentions about a practical example in China. "Computer communiction" is a required curriculum in most universities, so "Virtual Communicating Experimental System" is developed to help teaching in TianJin Normal University.

  1. Laboratory study of forced rotating shallow water turbulence

    Science.gov (United States)

    Espa, Stefania; Di Nitto, Gabriella; Cenedese, Antonio

    2011-12-01

    During the last three decades several authors have studied the appearance of multiple zonal jets in planetary atmospheres and in the Earths oceans. The appearance of zonal jets has been recovered in numerical simulations (Yoden & Yamada, 1993), laboratory experiments (Afanasyev & Wells, 2005; Espa et al., 2008, 2010) and in field measurements of the atmosphere of giant planets (Galperin et al., 2001). Recent studies have revealed the presence of zonation also in the Earths oceans, in fact zonal jets have been found in the outputs of Oceanic General Circulation Models-GCMs (Nakano & Hasumi, 2005) and from the analysis of satellite altimetry observations (Maximenko et al., 2005). In previous works (Espa et al., 2008, 2010) we have investigated the impact of the variation of the rotation rate and of the fluid depth on jets organization in decaying and forced regimes. In this work we show results from experiments performed in a bigger domain in which the fluid is forced continuously. The experimental set-up consists of a rotating tank (1m in diameter) where the initial distribution of vorticity has been generated via the Lorentz force in an electromagnetic cell. The latitudinal variation of the Coriolis parameter has been simulated by the parabolic profile assumed by the free surface of the rotating fluid. Flow measurements have been performed using an image analysis technique. Experiments have been performed changing the tank rotation rate and the fluid thickness. We have investigated the flow in terms of zonal and radial flow pattern, flow variability and jet scales.

  2. Chemical reaction and dust formation studies in laboratory hydrocarbon plasmas.

    Science.gov (United States)

    Hippler, Rainer; Majumdar, Abhijit; Thejaswini, H. C.

    Plasma chemical reaction studies with relevance to, e.g., Titan's atmosphere have been per-formed in various laboratory plasmas [1,2]. Chemical reactions in a dielectric barrier discharge at medium pressure of 250-300 mbar have been studied in CH4 /N2 and CH4 /Ar gas mixtures by means of mass spectrometry. The main reaction scheme is production of H2 by fragmenta-tion of CH4 , but also production of larger hydrocarbons like Cn Hm with n up to 10 including formation of different functional CN groups is observed. [1] A. Majumdar and R. Hippler, Development of dielectric barrier discharge plasma processing apparatus for mass spectrometry and thin film deposition, Rev. Sci. Instrum. 78, 075103 (2007) [2] H.T. Do, G. Thieme, M. Frühlich, H. Kersten, and R. Hippler, Ion Molecule and Dust Particle Formation in Ar/CH4 , Ar/C2 H2 and Ar/C3 H6 Radio-frequency Plasmas, Contrib. Plasma Phys. 45, No. 5-6, 378-384 (2005)

  3. New Laboratory and Field Studies on Shatter Cones

    Science.gov (United States)

    Zaag, P. T.; Hasch, M.; Reimold, W. U.; Raschke, U.; Hipsley, C. A.; Hess, K.-U.; Dobson, K. J.

    2015-09-01

    Investigations of orientation, distribution, and shock micro-deformation of shatter cones were undertaken with micro-Computed Tomography and polarizing microscopy in the laboratory, and in the field at the Keurusselkä impact structure (Finland).

  4. Comparative study of effects of table sugar, laboratory grade ...

    African Journals Online (AJOL)

    cntaganda

    four weeks, plants grown on the culture medium with laboratory grade sucrose showed consistently ... characteristics to those grown in the field (ZRYD, 1988). ... electrical neutrality, and its apparent lack of inhibitory effect on the majority of.

  5. A laboratory study of the composition and fermentation of various ...

    African Journals Online (AJOL)

    Grain sorghum, forage sorghum, sunflower and maize were ensiled on laboratory scale. Sunflowers ..... to the bacteria during fermentation without further degradation of .... additions of urea, dried whey and sodium hydroxide. J. Anim. Sci.

  6. Laboratory Studies of Sea-Ice-Wave Interactions

    Science.gov (United States)

    Monty, J.; Meylan, M. H.; Babanin, A. V.; Toffoli, A.; Bennetts, L.

    2016-12-01

    A world-first facility for studying the Marginal Ice Zone has been constructed in the Michell Hydrodynamics Laboratory at the University of Melbourne. A 14m long wave tank (0.75m wide, 0.6m deep) resides in a freezer, where air temperature can be controlled down to -15C. This permits the freezing of the water surface. Large stainless steel ice-making trays (up to 4 m long) are also available to create ice of desired thickness and microstructure, which can be lowered onto the water surface. A computer controlled wave generator is capable of creating waves of any desired form. The temperature of the water in the tank can also be controlled between 2 and 30C. The tank frame is constructed of marine-treated wood and the entire tank is glass and acrylic, permitting the use of corrosive fluids, such as salt water. Here we present the first laboratory experiments of break-up of a controlled thickness, fresh water ice sheet impacted by regular and JONSWAP spectrum surface waves. The geometry of the resultant ice-floes is measured with high-resolution, time-resolved imaging, providing the crucial data of floe size distribution. Initial observations show that, in the case of high steepness waves, the primary mechanisms of ice break-up at the ice edge are overwash and rafting, both of which put weight on the ice interior to the ice-water interface. This additional weight (and impact in the case of rafting) breaks more ice, which allows overwash and rafting deeper into the ice sheet, breaking more ice and so on. For lower steepness waves, overwash and rafting are still present but far less significant. Finally, results of vertical ice movement using laser height gauges will be presented showing the attenuation of waves into an ice sheet and through a pack of ice floes. These results are compared with field data and theory available (e.g. Squire & Moore, Nature, 1980 and Kohout et al., Nature, 2014).

  7. Asymmetry of wind waves studied in a laboratory tank

    Science.gov (United States)

    Ileykin, L. A.; Donelan, M. A.; Mellen, R. H.; McLaughlin, D. J.

    1995-03-01

    Asymmetry of wind waves was studied in laboratory tank tinder varied wind and fetch conditions using both bispectral analysis of wave records and third-order statistics of the surface elevation. It is found skewness S (the normalized third-order moment of surface elevation describing the horizontal asymmetry waves) varies only slightly with the inverse wave u*/Cm (where u* is the air friction velocity and Cm is phase speed of the dominant waves). At the same time asymmetry A, which is determined from the Hilbert transform of the wave record and characterizes the skewness of the rate of change of surface elevation, increase consistently in magnitude with the ratio u*/Cm. This suggests that nonlinear distortion of the wave profile determined by the degree of wind forcing and is a sensitive indicator of wind-wave interaction processes. It is shown that the asymmetric profile of waves can described within the frameworks of the nonlinear nonspectral concept (Plate, 1972; Lake and Yuen, 197 according to which the wind-wave field can be represented as a coherent bound-wave system consisting mainly of dominant component w. and its harmonics propagating with the same speed C. , as observed by Ramamonjiaris and Coantic (1976). The phase shift between o). harmonics is found and shown to increase with the asymmetry of the waves.

  8. Asymmetry of wind waves studied in a laboratory tank

    Directory of Open Access Journals (Sweden)

    I. A. Leykin

    1995-01-01

    Full Text Available Asymmetry of wind waves was studied in laboratory tank tinder varied wind and fetch conditions using both bispectral analysis of wave records and third-order statistics of the surface elevation. It is found skewness S (the normalized third-order moment of surface elevation describing the horizontal asymmetry waves varies only slightly with the inverse wave u*/Cm (where u* is the air friction velocity and Cm is phase speed of the dominant waves. At the same time asymmetry A, which is determined from the Hilbert transform of the wave record and characterizes the skewness of the rate of change of surface elevation, increase consistently in magnitude with the ratio u*/Cm. This suggests that nonlinear distortion of the wave profile determined by the degree of wind forcing and is a sensitive indicator of wind-wave interaction processes. It is shown that the asymmetric profile of waves can described within the frameworks of the nonlinear nonspectral concept (Plate, 1972; Lake and Yuen, 197 according to which the wind-wave field can be represented as a coherent bound-wave system consisting mainly of dominant component w. and its harmonics propagating with the same speed C. , as observed by Ramamonjiaris and Coantic (1976. The phase shift between o. harmonics is found and shown to increase with the asymmetry of the waves.

  9. A laboratory study on groundwater quality and mass movement occurrence

    Science.gov (United States)

    Fan, Jen-Chen; Liu, Che-Hsin; Yang, Chih-Hsiang; Huang, Hsiao-Yu

    2009-06-01

    In this study, soil samples collected from the sides of two streams with high debris flow potential at Shenmu and Fengchiou village in Nantou County, Taiwan, were used for seepage tank tests in the laboratory. While the tests were being conducted, observations were made to investigate the relationships among displacement of the slope, quality of the seepage water and occurrence of mass movement. The results showed that according to the change rate, displacement could be divided into two stages, namely, the initial failure displacement stage and primary failure displacement stage. While the displacement of the slope was in primary failure displacement stages, the probability of slope failure became much higher. Before general slope failure, electrical conductivity (EC) and sulfate ion (SO4 2-) concentration of the seepage water increased significantly. The time when EC of the seepage water started to increase rapidly was much earlier than that when displacement of the slope started to increase significantly. Therefore, from the hazard mitigation view, there will be a longer time for response if EC of the seepage water was monitored.

  10. Laboratory studies of aeolian sediment transport processes on planetary surfaces

    Science.gov (United States)

    Rasmussen, Keld R.; Valance, Alexandre; Merrison, Jonathan

    2015-09-01

    We review selected experimental saltation studies performed in laboratory wind tunnels and collision experiments performed in (splash-) laboratory facilities that allow detailed observations between impinging particles on a stationary bed. We also discuss progress in understanding aeolian transport in nonterrestrial environments. Saltation studies in terrestrial wind tunnels can be divided into two groups. The first group comprises studies using a short test bed, typically 1-4 m long, and focuses on the transitional behavior near the upwind roughness discontinuity where saltation starts. The other group focuses on studies using long test beds - typically 6 m or more - where the saturated saltation takes place under equilibrium conditions between wind flow and the underlying rough bed. Splash studies using upscaled model experiments allow collision simulations with large spherical particles to be recorded with a high speed video camera. The findings indicate that the number of ejected particles per impact scales linearly with the impact velocity of the saltating particles. Studies of saturated saltation in several facilities using predominantly Particle Tracking Velocimetry or Laser Doppler Velocimetry indicate that the velocity of the (few) particles having high trajectories increases with increasing friction velocity. However, the speed of the majority of particles that do not reach much higher than Bagnold's focal point is virtually independent of Shields parameter - at least for low or intermediate u*-values. In this case mass flux depends on friction velocity squared and not cubed as originally suggested by Bagnold. Over short beds particle velocity shows stronger dependence on friction velocity and profiles of particle velocity deviate from those obtained over long beds. Measurements using horizontally segmented traps give average saltation jump-lengths near 60-70 mm and appear to be only weakly dependent on friction velocity, which is in agreement with some

  11. Field and laboratory procedures used in a soil chronosequence study

    Science.gov (United States)

    Singer, Michael J.; Janitzky, Peter

    1986-01-01

    In 1978, the late Denis Marchand initiated a research project entitled "Soil Correlation and Dating at the U.S. Geological Survey" to determine the usefulness of soils in solving geologic problems. Marchand proposed to establish soil chronosequences that could be dated independently of soil development by using radiometric and other numeric dating methods. In addition, by comparing dated chronosequences in different environments, rates of soil development could be studied and compared among varying climates and mineralogical conditions. The project was fundamental in documenting the value of soils in studies of mapping, correlating, and dating late Cenozoic deposits and in studying soil genesis. All published reports by members of the project are included in the bibliography.The project demanded that methods be adapted or developed to ensure comparability over a wide variation in soil types. Emphasis was placed on obtaining professional expertise and on establishing consistent techniques, especially for the field, laboratory, and data-compilation methods. Since 1978, twelve chronosequences have been sampled and analyzed by members of this project, and methods have been established and used consistently for analysis of the samples.The goals of this report are to:Document the methods used for the study on soil chronosequences,Present the results of tests that were run for precision, accuracy, and effectiveness, andDiscuss our modifications to standard procedures.Many of the methods presented herein are standard and have been reported elsewhere. However, we assume less prior analytical knowledge in our descriptions; thus, the manual should be easy to follow for the inexperienced analyst. Each chapter presents one or more references of the basic principle, an equipment and reagents list, and the detailed procedure. In some chapters this is followed by additional remarks or example calculations.The flow diagram in figure 1 outlines the step-by-step procedures used to

  12. Field and Laboratory Studies of Atmospheric Organic Aerosol

    Science.gov (United States)

    Coggon, Matthew Mitchell

    This thesis is the culmination of field and laboratory studies aimed at assessing processes that affect the composition and distribution of atmospheric organic aerosol. An emphasis is placed on measurements conducted using compact and high-resolution Aerodyne Aerosol Mass Spectrometers (AMS). The first three chapters summarize results from aircraft campaigns designed to evaluate anthropogenic and biogenic impacts on marine aerosol and clouds off the coast of California. Subsequent chapters describe laboratory studies intended to evaluate gas and particle-phase mechanisms of organic aerosol oxidation. The 2013 Nucleation in California Experiment (NiCE) was a campaign designed to study environments impacted by nucleated and/or freshly formed aerosol particles. Terrestrial biogenic aerosol with > 85% organic mass was observed to reside in the free troposphere above marine stratocumulus. This biogenic organic aerosol (BOA) originated from the Northwestern United States and was transported to the marine atmosphere during periodic cloud-clearing events. Spectra recorded by a cloud condensation nuclei counter demonstrated that BOA is CCN active. BOA enhancements at latitudes north of San Francisco, CA coincided with enhanced cloud water concentrations of organic species such as acetate and formate. Airborne measurements conducted during the 2011 Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE) were aimed at evaluating the contribution of ship emissions to the properties of marine aerosol and clouds off the coast of central California. In one study, analysis of organic aerosol mass spectra during periods of enhanced shipping activity yielded unique tracers indicative of cloud-processed ship emissions (m/z 42 and 99). The variation of their organic fraction (f42 and f 99) was found to coincide with periods of heavy (f 42 > 0.15; f99 > 0.04), moderate (0.05 < f42 < 0.15; 0.01 < f99 < 0.04), and negligible (f42 < 0.05; f99 < 0.01) ship influence. Application of

  13. Los Alamos National Laboratory W76 Pit Tube Lifetime Study

    Energy Technology Data Exchange (ETDEWEB)

    Abeln, Terri G. [Los Alamos National Laboratory

    2012-04-25

    A metallurgical study was requested as part of the Los Alamos National Laboratory (LANL) W76-1 life-extension program (LEP) involving a lifetime analysis of type 304 stainless steel pit tubes subject to repeat bending loads during assembly and disassembly operations at BWXT/Pantex. This initial test phase was completed during the calendar years of 2004-2006 and the report not issued until additional recommended tests could be performed. These tests have not been funded to this date and therefore this report is considered final. Tubes were reportedly fabricated according to Rocky Flats specification P14548 - Seamless Type 304 VIM/VAR Stainless Steel Tubing. Tube diameter was specified as 0.125 inches and wall thickness as 0.028 inches. A heat treat condition is not specified and the hardness range specification can be characteristic of both 1/8 and 1/4 hard conditions. Properties of all tubes tested were within specification. Metallographic analysis could not conclusively determine a specified limit to number of bends allowable. A statistical analysis suggests a range of 5-7 bends with a 99.95% confidence limit. See the 'Statistical Analysis' section of this report. The initial phase of this study involved two separate sets of test specimens. The first group was part of an investigation originating in the ESA-GTS [now Gas Transfer Systems (W-7) Group]. After the bend cycle test parameters were chosen (all three required bends subjected to the same amount of bend cycles) and the tubes bent, the investigation was transferred to Terri Abeln (Metallurgical Science and Engineering) for analysis. Subsequently, another limited quantity of tubes became available for testing and were cycled with the same bending fixture, but with different test parameters determined by T. Abeln.

  14. Pinon Pine Tree Study, Los Alamos National Laboratory: Source document

    Energy Technology Data Exchange (ETDEWEB)

    P. R. Fresquez; J. D. Huchton; M. A. Mullen; L. Naranjo, Jr.

    2000-01-01

    One of the dominant tree species growing within and around Los Alamos National Laboratory (LANL), Los Alamos, NM, lands is the pinon pine (Pinus edulis) tree. Pinon pine is used for firewood, fence posts, and building materials and is a source of nuts for food--the seeds are consumed by a wide variety of animals and are also gathered by people in the area and eaten raw or roasted. This study investigated the (1) concentration of {sup 3}H, {sup 137}Cs, {sup 90}Sr, {sup tot}U, {sup 238}Pu, {sup 239,240}Pu, and {sup 241}Am in soils (0- to 12-in. [31 cm] depth underneath the tree), pinon pine shoots (PPS), and pinon pine nuts (PPN) collected from LANL lands and regional background (BG) locations, (2) concentrations of radionuclides in PPN collected in 1977 to present data, (3) committed effective dose equivalent (CEDE) from the ingestion of nuts, and (4) soil to PPS to PPN concentration ratios (CRs). Most radionuclides, with the exception of {sup 3}H in soils, were not significantly higher (p < 0.10) in soils, PPS, and PPN collected from LANL as compared to BG locations, and concentrations of most radionuclides in PPN from LANL have decreased over time. The maximum net CEDE (the CEDE plus two sigma minus BG) at the most conservative ingestion rate (10 lb [4.5 kg]) was 0.0018 mrem (0.018 {micro}Sv). Soil-to-nut CRs for most radionuclides were within the range of default values in the literature for common fruits and vegetables.

  15. Laboratory work and pregnancy outcomes: a study within the National Birth Cohort in Denmark

    DEFF Research Database (Denmark)

    Zhu, J L; Knudsen, Lisbeth E.; Andersen, Anne-Marie Nybo;

    2006-01-01

    AIMS: To examine pregnancy outcomes in women doing laboratory work. METHODS: Using data from the Danish National Birth Cohort (1997-2003), the authors conducted a prospective cohort study of 1025 female laboratory technicians and 8037 female teachers (as reference). The laboratory technicians wer...

  16. Microbial Evolution at High Pressure: Deep Sea and Laboratory Studies

    Science.gov (United States)

    Bartlett, D. H.

    2011-12-01

    Elevated hydrostatic pressures are present in deep-sea and deep-Earth environments where this physical parameter has influenced the evolution and characteristics of life. Piezophilic (high-pressure-adapted) microbes have been isolated from diverse deep-sea settings, and would appear likely to occur in deep-subsurface habitats as well. In order to discern the factors enabling life at high pressure my research group has explored these adaptations at various levels, most recently including molecular analyses of deep-sea trench communities, and through the selective evolution of the model microbe Escherichia coli in the laboratory to progressively higher pressures. Much of the field work has focused on the microbes present in the deeper portions of the Puerto Rico Trench (PRT)and in the Peru-Chile Trench (PCT), from 6-8.5 km below the sea surface (~60-85 megapascals pressure). Culture-independent phylogenetic data on the Bacteria and Archaea present on particles or free-living, along with data on the microeukarya present was complemented with genomic analyses and the isolation and characterization of microbes in culture. Metagenomic analyses of the PRT revealed increased genome sizes and an overrepresentation at depth of sulfatases for the breakdown of sulfated polysaccharides and specific categories of transporters, including those associated with the transport of diverse cations or carboxylate ions, or associated with heavy metal resistance. Single-cell genomic studies revealed several linneages which recruited to the PRT metagenome far better than existing marine microbial genome sequences. analyses. Novel high pressure culture approaches have yielded new piezophiles including species preferring very low nutrient levels, those living off of hydrocarbons, and those adapted to various electron donor/electron acceptor combinations. In order to more specifically focus on functions enabling life at increased pressure selective evolution experiments were performed with

  17. GPR monitoring of oil displacement - A laboratory study

    NARCIS (Netherlands)

    Miorali, M.; Slob, E.C.; Arts, R.J.

    2011-01-01

    In this paper we present laboratory experiments where we address the Ground Penetrating Radar (GPR) capability of monitoring oil displacement processes in porous media. This has significant applications in near-subsurface environments where remediation of contaminant such as oil-derived liquids is c

  18. Shining light on interstellar matter : a laboratory study

    NARCIS (Netherlands)

    Paardekooper, D.M.

    2016-01-01

    In recent years it has become clear that the space in between the stars, contains a remarkable amount of highly diverse molecules, ranging from simple diatomics to large complex species. Astronomical observations and dedicated laboratory experiments show that icy dust grains play a prominent role in

  19. An Undergraduate Laboratory Exercise for Studying Kinetics of Batch Crystallization

    Science.gov (United States)

    Louhi­-Kultanen, Marjatta; Han, Bing; Nurkka, Annikka; Hatakka, Henry

    2015-01-01

    The present work describes an undergraduate laboratory exercise for improving understanding of fundamental phenomena in cooling crystallization. The exercise of nucleation and crystal growth kinetics supports learning of theories and models presented in lectures and calculation exercises. The teaching methodology incorporates precepts the…

  20. Waste management study: Process development at Lawrence Livermore National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    1984-12-01

    This report presents the results of an evaluation of the present Toxic Waste Control Operations at the Lawrence Livermore National Laboratory, evaluates the technologies most applicable to the treatment of toxic and hazardous wastes and presents conceptual designs of processes for the installation of a new decontamination and waste treatment facility (DWTF) for future treatment of these wastes.

  1. GPR monitoring of oil displacement - A laboratory study

    NARCIS (Netherlands)

    Miorali, M.; Slob, E.C.; Arts, R.J.

    2011-01-01

    In this paper we present laboratory experiments where we address the Ground Penetrating Radar (GPR) capability of monitoring oil displacement processes in porous media. This has significant applications in near-subsurface environments where remediation of contaminant such as oil-derived liquids is

  2. Case study: improving efficiency in a large hospital laboratory.

    Science.gov (United States)

    Bartel, Marilynn

    2004-01-01

    Saint Francis Health System (SFHS) consists of three hospitals and one clinic: Saint Francis Hospital (SFH); Broken Arrow Medical Center; Laureate Psychiatric Hospital; and Warren Clinic. SFHS has 670 physicians on staff and serves medical (oncology, orthopedic, neurology, and renal), surgical, cardiac, women and infant, pediatric, transplant, and trauma patients in Tulsa County, Oklahoma, which has a population of 660,000. SFH incorporates 706 staffed beds, including 126 pediatric beds and 119 critical care beds. Each year, the health system averages 38,000 admissions, 70,000 emergency department visits, 25,000 surgeries, and 3,500 births. Saint Francis Laboratory is located within the main hospital facility (SFH) and functions as a core lab for the health system. The lab also coordinates lab services with Saint Francis Heart Hospital, a physician-system joint venture. The Optimal Equipment Configuration (OEC) Project was designed by the Clinical Laboratory Services division of Premier, a group purchasing organization, with the goal of determining whether laboratories could improve efficiency and decrease unit cost by using a single-source vendor. Participants included seven business partners (Abbott, Bayer, Beckman/Coulter, Dade/Behring, J&J/ Ortho, Olympus, and Roche) and 21 laboratory sites (a small, mid-sized, and large site for each vendor). SFH laboratory staff embraced Premier's concept and viewed the OEC project as an opportunity to "energize" laboratory operations. SFH partnered with Abbott, their primary equipment vendor, for the project. Using resources and tools made available through the project, the laboratory was re-engineered to simplify workflow, increase productivity, and decrease costs by adding automation and changing to centralized specimen processing. Abbott and SFH shared a common vision for the project and enhanced their partnership through increased communication and problem solving. Abbott's area representatives provided for third

  3. Laboratory studies of imitation/field studies of tradition: towards a synthesis in animal social learning.

    Science.gov (United States)

    Galef, Bennett G

    2015-03-01

    Here I discuss: (1) historical precedents that have resulted in comparative psychologists accepting the two-action method as the "gold standard" in laboratory investigations of imitation learning, (2) evidence suggesting that the two-action procedure may not be adequate to answer questions concerning the role of imitation in the development of traditional behaviors of animals living in natural habitat, and (3) an alternative approach to the laboratory study of imitation that might increase the relevance of laboratory studies of imitation to the work of behavioral ecologists/primatologists interested in animal traditions and their relationship to human cumulative culture. This article is part of a Special Issue entitled: Tribute to Tom Zentall.

  4. Aboriginal Children and Their Caregivers Living with Low Income: Outcomes from a Two-Generation Preschool Program

    OpenAIRE

    Benzies, Karen; Tough, Suzanne; Edwards, Nancy; Mychasiuk, Richelle; Donnelly, Carlene

    2010-01-01

    The development of preschool children of Aboriginal heritage is jeopardized by the inter-generational transmission of risk that has created, and continues to create, social disadvantage. Early intervention programs are intended to mitigate the impact of social disadvantage. Yet, evidence of the effectiveness of these programs for children of Aboriginal heritage is limited. The purpose of this study was to examine the effects of a two-generation, multi-cultural preschool program on 45 children...

  5. Behavioural risk factors in two generations of non-Western migrants: do trends converge towards the host population?

    OpenAIRE

    Hosper, K.; Nierkens, V.; Nicolaou, M; Stronks, K

    2007-01-01

    Migrant mortality does not conform to a single pattern of convergence towards prevalence rates in the host population. To understand better how migrant mortality develops, it is necessary to further investigate how the underlying behavioural determinants change following migration. We studied whether the prevalence of behavioural risk factors over two generations of Turkish and Moroccan migrants converge towards the prevalence rates in the Dutch population. From a random sample from the popul...

  6. Aboriginal Children and Their Caregivers Living with Low Income: Outcomes from a Two-Generation Preschool Program

    OpenAIRE

    Benzies, Karen; Tough, Suzanne; Edwards, Nancy; Mychasiuk, Richelle; Donnelly, Carlene

    2010-01-01

    The development of preschool children of Aboriginal heritage is jeopardized by the inter-generational transmission of risk that has created, and continues to create, social disadvantage. Early intervention programs are intended to mitigate the impact of social disadvantage. Yet, evidence of the effectiveness of these programs for children of Aboriginal heritage is limited. The purpose of this study was to examine the effects of a two-generation, multi-cultural preschool program on 45 children...

  7. Laboratory Studies of Halogen Oxides Important to Stratospheric Ozone Depletion

    Science.gov (United States)

    Wilmouth, D. M.; Klobas, J. E.; Anderson, J. G.

    2016-12-01

    Inorganic chlorine and bromine molecules are primarily responsible for stratospheric ozone destruction, with BrO, ClO, and ClOOCl comprising the two reaction cycles that cause most polar ozone losses. Despite comprehensive international treaties regulating CFCs and halons, seasonal polar ozone depletion will likely continue for decades to come. Accurate spectroscopic and kinetic measurements of inorganic bromine and chlorine molecules obtained in the laboratory are essential for reducing uncertainty in atmospheric models, better interpreting atmospheric field measurements, and forming trusted projections of future ozone changes. Here we present results from recent work in our laboratory using absorption spectroscopy and atomic resonance fluorescence detection to determine rate constants of halogen reactions, the equilibrium constant of ClO/ClOOCl, and absorption cross sections of several halogen oxides using a new cold trap-thermal desorption approach.

  8. A combined supplementation of vitamin B12 and omega-3 fatty acids across two generations improves cardiometabolic variables in rats.

    Science.gov (United States)

    Khaire, Amrita; Rathod, Richa; Randhir, Karuna; Kale, Anvita; Joshi, Sadhana

    2016-09-14

    Our earlier studies indicate that micronutrients (vitamin B12, folic acid) and omega-3 fatty acids especially docosahexaenoic acid (DHA) are interlinked in one carbon cycle. The present study examines the effects of a sustained vitamin B12 deficiency/supplementation in the presence of omega-3 fatty acids across two generations on the pregnancy outcome and cardiometabolic profile [blood pressure, plasma lipid profile (cholesterol and triglycerides), plasma/liver fatty acid profile and hepatic lipid metabolism] in the second generation adult Wistar rat offspring. Two generations of animals were fed the following diets: control; vitamin B12 deficient; vitamin B12 supplemented; vitamin B12 deficient diet supplemented with omega-3 fatty acids; vitamin B12 and omega-3 fatty acid supplemented diets. Male offspring were sacrificed at 3 months of age. Vitamin B12 deficiency lowered the weight gain (p B12 supplementation showed weight gain, blood pressure and the fatty acid profile similar to the control. However, it increased (p B12 deficient group lowered the weight gain although the levels of cardiometabolic variables were comparable to the control. Omega-3 fatty acid supplementation in the presence of vitamin B12 improved the pregnancy outcome and all cardio-metabolic variables. Our study highlights the adverse effects of sustained vitamin B12 deficiency across two generations on the pregnancy outcome, fatty acid profile and blood pressure while a combined supplementation of vitamin B12 and omega-3 fatty acids is beneficial.

  9. Honey and propolis production, hygiene and defense behaviors of two generations of Africanized honey bees

    Directory of Open Access Journals (Sweden)

    Regina Conceição Garcia

    2013-04-01

    Full Text Available Phenotypic characters of honeybees, relevant to beekeepers, can be evaluated by studying correlations between them, and the correlated characteristics can be evaluated in the short term to assist in monitoring of annual genetic progress. This work therefore aims to evaluate the production of honey and propolis, the hygiene and defensive behaviours of two generations of Africanized Apis mellifera (Hymenoptera, Apidae, to estimate the correlations between them and their heritability. We used 30 Langstroth beehives in apiaries in Marechal Cândido Rondon, Paraná State, Brazil. We used a method of drilling pupae to evaluate hygiene behaviour and the velveteen ball method to test defensive behaviour. We selected ten colonies which had the best honey and propolis production, and which produced F1 queens that were then transferred to beehives at an experimental farm, in order to observe honey and propolis production, hygiene and defence behaviours of their female offspring. The estimated differences for each characteristic between the generations, the correlations between them within each generation and their heritability suggest that selection of colonies based on propolis production was more efficient at maintaining this high production than was selection based on honey production according to the performance of the colonies for this characteristic. The selected behavioural characteristics can be used to enhance performance, but not for improving yield characteristics evaluated.

  10. A laboratory nanoseismological study on deep-focus earthquake micromechanics

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yanbin; Zhu, Lupei; Shi, Feng; Schubnel, Alexandre; Hilairet, Nadege; Yu, Tony; Rivers, Mark; Gasc, Julien; Addad, Ahmed; Deldicque, Damien; Li, Ziyu; Brunet, Fabrice

    2017-07-01

    Global earthquake occurring rate displays an exponential decay down to ~300 km and then peaks around 550 to 600 km before terminating abruptly near 700 km. How fractures initiate, nucleate, and propagate at these depths remains one of the greatest puzzles in earth science, as increasing pressure inhibits fracture propagation. We report nanoseismological analysis on high-resolution acoustic emission (AE) records obtained during ruptures triggered by partial transformation from olivine to spinel in Mg2GeO4, an analog to the dominant mineral (Mg,Fe)2SiO4 olivine in the upper mantle, using state-of-the-art seismological techniques, in the laboratory. AEs’ focal mechanisms, as well as their distribution in both space and time during deformation, are carefully analyzed. Microstructure analysis shows that AEs are produced by the dynamic propagation of shear bands consisting of nanograined spinel. These nanoshear bands have a near constant thickness (~100 nm) but varying lengths and self-organize during deformation. This precursory seismic process leads to ultimate macroscopic failure of the samples. Several source parameters of AE events were extracted from the recorded waveforms, allowing close tracking of event initiation, clustering, and propagation throughout the deformation/transformation process. AEs follow the Gutenberg-Richter statistics with a well-defined b value of 1.5 over three orders of moment magnitudes, suggesting that laboratory failure processes are self-affine. The seismic relation between magnitude and rupture area correctly predicts AE magnitude at millimeter scales. A rupture propagation model based on strain localization theory is proposed. Future numerical analyses may help resolve scaling issues between laboratory AE events and deep-focus earthquakes.

  11. Laboratory studies of corona emissions from air terminals

    Science.gov (United States)

    D'Alessandro, F.; Berger, G.

    1999-11-01

    This paper presents some of the results obtained from a systematic series of laboratory investigations into the corona emission characteristics of air terminals. Two particular aspects are considered, namely the effect on corona emission of changing the distance between the tip of the air terminal and the overhead energized electrode, and the relationship between the two fundamental corona parameters (`amplitude coefficient' and onset electric field) and the height of the air terminal above a ground plane. The implications of the results for lightning protection designs are discussed.

  12. Toxicological study of plant extracts on termite and laboratory animals.

    Science.gov (United States)

    Rahman, I; Gogoi, Inee; Dolui, A K; Handique, Ruma

    2005-04-01

    Toxic activity of leaf extracts of Polygonum hydropiper L. and Pogostemon parviflorus Benth. were tested in the laboratory against tea termite, Odontotermes assamensis Holm. Both the tested extracts caused mortality of the termite. The highest toxic activity (100%) was found in the 2.0% chloroform extracts of P. hydropiper. The chloroform extract of P. hydropiper was explored for possible mammalian toxicological effects. The LD50 was 758.58 mg/kg in male albino mice. Subcutaneous injection of sub-lethal dose of extract into male mice once a week for 6 weeks failed to express any significant influence on WBC, RBC count and blood cholesterol.

  13. Laboratory Studies of the Fe K-shell Emission

    Energy Technology Data Exchange (ETDEWEB)

    Beiersdorfer, P

    2004-12-26

    An overview is given of measurements of the Fe K-shell spectrum from low-density laboratory sources. The measurements include wavelengths, electron-impact collision cross sections, innershell ionization phenomena, dielectronic recombination resonance strengths, charge exchange recombination, electron beam polarization effects, resonance excitation, and radiative cascade contributions. K-shell spectra have now also been obtained with microcalorimeters, including microcalorimeter arrays that are twins of the ASTRO-E and ASTRO-E2 missions, which illustrate typical resolving powers and spectral capabilities.

  14. Renewable Energy Laboratory Development for Biofuels Advanced Combustion Studies

    Energy Technology Data Exchange (ETDEWEB)

    Soloiu, Valentin A. [Georgia Southern Univ., Statesboro, GA (United States)

    2012-03-31

    The research advanced fundamental science and applied engineering for increasing the efficiency of internal combustion engines and meeting emissions regulations with biofuels. The project developed a laboratory with new experiments and allowed investigation of new fuels and their combustion and emissions. This project supports a sustainable domestic biofuels and automotive industry creating economic opportunities across the nation, reducing the dependence on foreign oil, and enhancing U.S. energy security. The one year period of research developed fundamental knowledge and applied technology in advanced combustion, emissions and biofuels formulation to increase vehicle's efficiency. Biofuels combustion was investigated in a Compression Ignition Direct Injection (DI) to develop idling strategies with biofuels and an Indirect Diesel Injection (IDI) intended for auxiliary power unit.

  15. Renewable Energy Laboratory Development for Biofuels Advanced Combustion Studies

    Energy Technology Data Exchange (ETDEWEB)

    Soloiu, Valentin [Georgia Southern Univ., Statesboro, GA (United States)

    2012-03-31

    The research advanced fundamental science and applied engineering for increasing the efficiency of internal combustion engines and meeting emissions regulations with biofuels. The project developed a laboratory with new experiments and allowed investigation of new fuels and their combustion and emissions. This project supports a sustainable domestic biofuels and automotive industry creating economic opportunities across the nation, reducing the dependence on foreign oil, and enhancing U.S. energy security. The one year period of research developed fundamental knowledge and applied technology in advanced combustion, emissions and biofuels formulation to increase vehicle's efficiency. Biofuels combustion was investigated in a Compression Ignition Direct Injection (DI) to develop idling strategies with biofuels and an Indirect Diesel Injection (IDI) intended for auxiliary power unit.

  16. Creating Opportunity for Families: A Two-Generation Approach. KIDS COUNT Policy Report

    Science.gov (United States)

    Gencer, Arin

    2014-01-01

    Nearly half of the nation's families with young children struggle to make ends meet. A new KIDS COUNT policy report makes the case for creating opportunity for families by addressing the needs of parents and their children simultaneously. "Creating Opportunity for Families: A Two-Generation Approach" describes a new approach to reducing…

  17. ISSUES IN DEVELOPING A TWO-GENERATION AVIAN TOXICITY TEST WITH JAPANESE QUAIL

    Science.gov (United States)

    As a subgroup of the OECD Expert Group on Assessment of Endocrine Disrupting Effects in Birds, we reviewed unresolved methodological issures important for the development of a two-generation toxicity test, discussed advantages and disadvantages of alternative approaches, and prop...

  18. The physical activity and health status of two generations of Black South African professional women

    Directory of Open Access Journals (Sweden)

    Daniel J.L. Venter

    2011-02-01

    Full Text Available Increased health risks associated with physical inactivity in the Black population have been reported in recent years. Black women, suffering the highest levels of inactivity, overweight and obesity, are at greatest risk of developing chronic diseases of lifestyle. This explorativedescriptive study investigated the physical activity patterns and health status of two generations of Black professional women, reflecting pre-democracy and post-democracy age groups. Quantitative measures were used, including the ActiGraph GT1M accelerometer, the Global Physical Activity Questionnaire and the Health-Promoting Lifestyle Profile. Sample groups comprised teachers, nurses, social workers and public sector managers. Participants aged between 35 and 45 years were allocated to the older generation group (n = 111, whilst those aged between 18 and 21 years (students in the mentioned professional fields were allocated to the younger generation group (n = 69. The results indicated that these women displayed lower levels of health-promoting behavioural practices than expected, significantly lower levels of physical activity and significantly higher levels of overweight and obesity than the South African norms. The observation that the younger group appeared to be replicating the patterns of the older women is a cause of concern. Greater compliance to health-promoting behaviours was expected in this group owing to participants’ professional involvement in health, education and social development fields. Wide-ranging initiatives are necessary to promote physical activity and health amongst the Black female population in South Africa.

    Opsomming
    Gedurende die afgelope jare het navorsing onder die Swart bevolking ʼn toename in gesondheidsrisiko’s wat met fisieke onaktiwiteit geassosieer is, getoon. Swart vroue, wat die hoogste vlakke van onaktiwiteit, oorgewig en obesiteit toon, blyk ook die grootste risiko te loop om

  19. Design of laboratory experiments to study photoionization fronts

    Science.gov (United States)

    Drake, R. P.; Hazak, G.; Keiter, P. A.; Davis, J. S.; Patterson, C. R.; Frank, A.; Blackman, E.; Busquet, M.

    2016-10-01

    This paper analyzes the requirements of a photoionization-front experiment that could be driven in the laboratory, using thermal sources to produce the necessary flux of ionizing photons. It reports several associated conclusions. Such experiments will need to employ the largest available facilities, capable of delivering many kJ to MJ of energy to an x-ray source. They will use this source to irradiate a volume of neutral gas, likely of N, on a scale of a few mm to a few cm, increasing with source energy. For a gas pressure of several to ten atmospheres at room temperature, and a source temperature near 100 eV, one will be able to drive a photoionization front through a system of tens to hundreds of photon mean free paths. The front should make the familiar transition from the so-called R-Type to D-Type as the radiation flux diminishes with distance. The N is likely to reach the He-like state. Preheating from the energetic photons appears unlikely to become large enough to alter the essential dynamics of the front beyond some layer near the surface. For well-chosen experimental conditions, competing energy transport mechanisms are small. Supported by the U.S. DOE by NNSA Grants DE-NA0002956 (SSAA) and DE-NA0002719 (NLUF), by LLE, and by LLNL.

  20. Laboratory Studies of Cometary Materials - Continuity Between Asteroid and Comet

    Science.gov (United States)

    Messenger, Scott; Walker, Robert M.

    2015-01-01

    Laboratory analysis of cometary samples have been enabled by collection of cometary dust in the stratosphere by high altitude aircraft and by the direct sampling of the comet Wild-2 coma by the NASA Stardust spacecraft. Cometary materials are composed of a complex assemblage of highly primitive, unprocessed interstellar and primordial solar system materials as well as a variety of high temperature phases that must have condensed in the inner regions of the protoplanetary disk. These findings support and contradict conclusions of comet properties based solely on astronomical observations. These sample return missions have instead shown that there is a continuity of properties between comets and asteroids, where both types of materials show evidence for primitive and processed materials. Furthermore, these findings underscore the importance and value of direct sample return. There will be great value in comparing the findings of the Stardust cometary coma sample return mission with those of future asteroid surface sample returns OSIRIS-REx and Hayabusa II as well as future comet nucleus sample returns.

  1. Laboratory studies of biological effects of sulfur oxides

    Energy Technology Data Exchange (ETDEWEB)

    Dalbey, W. E.

    1979-01-01

    Selected results from exposures of laboratory animals to airborne sulfur oxides were briefly summarized. The main observation during acute exposures was reflex bronchoconstriction and a resultant increase in pulmonary resistance. The increase in resistance due to sulfur dioxide (SO/sub 2/) was potentiated by simultaneous exposure to aerosols under conditions which would increase the transfer of sulfur oxides into the respiratory tract and promote transformation to a higher oxidation state, especially one that is acid. Sulfate aerosols, particularly sulfuric acid aerosols, were more potent than SO/sub 2/ in causing bronchoconstriction. Chronic exposure to high concentrations (400 to 650 ppM) of SO/sub 2/ resulted in experimental bronchitis in several species. Longterm exposure to more realistic concentrations of SO/sub 2/ produced little or no changes in respiratory function or morphology. Significant alterations in both pulmonary function and morphology have been reported after chronic exposure to sulfuric acid aerosols. Recent data indicate that changes in the lung may progress after cessation of such exposures.

  2. SHELTER COMPETITION BETWEEN TWO INVASIVE CRAYFISH SPECIES: A LABORATORY STUDY

    Directory of Open Access Journals (Sweden)

    ALONSO F.

    2006-01-01

    Full Text Available Alien crayfishes represent a common threat to aquatic ecosystems. Their spread in Europe is leading to more frequent contacts between different invasive species populations. Shelter can be an important factor in the resulting interactions. A laboratory experiment was designed to analyse the competition for shelter in similarly sized males of two species that show an invasive behaviour in Spain, Pacifastacus leniusculus and Procambarus clarkii. We carried out 24 heterospecific, six-hour trials, with 30 min behavioural observations per hour. Most often, red swamp crayfish were both the first (70.8% and the long-term winner (62.5%. Usually, the long-term winner was the first winner. Whenever shelter was occupied, a passive behaviour by unsheltered individuals was more frequent in signal crayfish than in red swamp crayfish. When both were unsheltered, signal crayfish displayed more often a passive behaviour. Although the observed behaviour might be explained as the result of dominance by the red swamp crayfish over the signal crayfish, shelter availability and class, as well as different growth patterns and population size structures, could change the intensity and the outcome of the encounters in the wild, where signal crayfish usually reach larger sizes than red swamp crayfish.

  3. Laboratory studies for stone conservation at the Cathedral of Murcia

    Directory of Open Access Journals (Sweden)

    Esbert, R. M.

    1990-03-01

    Full Text Available The results of a series of laboratory tests, carried out on the bioclastic limestone used in the construction of the Murcia cathedral, are presented in this paper in order to evaluate the efficiency of certain treatment products, that eventually could be applied to that stone for improving their state of conservation. Additionally, the behaviour under accelerated ageing tests of non treated samples and the treated ones with the different products employed -ethyl silicate, oligomeric polisiloxane and poliurethane-, is compared.

    En el presente trabajo se recogen los resultados de una serie de experimentos de laboratorio realizados con la caliza bioclástica utilizada en la construcción de la catedral de Murcia, con el fin de conocer la idoneidad de ciertos productos de tratamiento que eventualmente podrían aplicarse a dicha piedra para mejorar su estado de conservación. Además, se compara el comportamiento, frente a diversos ensayos de envejecimiento artificial acelerado, de la piedra sin tratar y tratada con los diferentes productos ensayados: silicato de etilo, polisiloxano oligomérico y poliuretano.

  4. The 1993 QUASIMEME laboratory-performance study: chlorobiphenyls in fish oil and standard solutions

    NARCIS (Netherlands)

    Wells, D.E.; Boer, de J.

    1994-01-01

    A laboratory-performance study has been undertaken to improve the measurement of chlorobiphenyls in marine biota as part of the QUASIMEME (EU - Measurement and Testing) project. Fifty-two laboratories were invited to participate, of which 47 returned data on nine congeners in iso-octane solution and

  5. Inter-laboratory comparison study for pyrrolizidine alkaloids in animal feed using spiked and incurred material

    NARCIS (Netherlands)

    Nijs, de W.C.M.; Elbers, I.J.W.; Mulder, P.P.J.

    2014-01-01

    Pyrrolizidine alkaloids (PAs) are hepatotoxic metabolites produced by plants. PAs in animal feed can cause acute or chronic intoxications in animals and can be transferred to milk. An inter-laboratory comparison study among 12 laboratories, using their own methods of analysis, was conducted for the

  6. A Feasibility Study for Mobile Marketing and Distribution Occupational Laboratories in North Dakota.

    Science.gov (United States)

    Kohns, Donald P.

    A study determined the feasibility of a mobile laboratory for marketing and distribution in North Dakota. It attempted to answer four questions: (1) What types of staffing, equipment, curriculum, and delivery systems are presently being utilized in mobile laboratories throughout the nation? (2) What significant information obtained from mobile…

  7. Laboratory and field studies on an Indian strain of the brine shrimp Artemia

    Digital Repository Service at National Institute of Oceanography (India)

    Royan, J.P.

    The Tuticorin strain of the brine shrimp @iArtemia@@ was studied under both laboratory and field conditions. Studies on the survival of the nauplii at different temperatures and salinities revealed that the nauplii preferred a salinity of 35 ppt...

  8. Analytical Laboratories

    Data.gov (United States)

    Federal Laboratory Consortium — NETL’s analytical laboratories in Pittsburgh, PA, and Albany, OR, give researchers access to the equipment they need to thoroughly study the properties of materials...

  9. Creating organizational innovations in countries in transition using Finnish change laboratory: A case study from Serbia

    Directory of Open Access Journals (Sweden)

    Bodrožić Zlatko

    2012-01-01

    Full Text Available The Finnish Change Laboratory intervention method has been used in several Western countries to support innovation and learning within organizations. This study explored the applicability of the Change Laboratory method to work activities in Eastern European transition economies. The case of a Change Laboratory project at a Serbian publishing house was examined and discussed. The Change Laboratory led to a clear break from previous models and resulted in a new, much more efficient model of work organization based on teams. The studied publishing house can be characterized as an innovator within a relatively laggard industry. This characteristic increased the Serbian publisher’s potential for developing “learning partnerships” with publishing activities in EU Member States. These “learning partnerships” enabled appropriate Western concepts to be found that could be used as stimuli to develop a new model of work for the publishing house during the Change Laboratory.

  10. The interface between clinicians and laboratory staff: A field study in northern Tanzania

    Directory of Open Access Journals (Sweden)

    Coosje J. Tuijn

    2014-04-01

    Full Text Available Background: Strengthening the communication and professional relationships between clinicians and laboratory workers is essential in order to positively change clinicians’ attitudes about the reliability of diagnostic tests, enhancing the use of laboratory diagnostics and, ultimately, improving patient care. We developed an analytical framework to gain insight into the factors that influence communication amongst health professionals.Objective: To explore whether the interaction between clinicians and laboratory workers influences the use of laboratory test results in clinical decision making.Methods: Four health facilities in northern Tanzania were selected using convenience sampling, whereas study participants were selected using purposive sampling. The quantitative and qualitative data collection methods included self-administered questionnaires; semistructured, individual interviews; in-depth, individual interviews; and/or focus group discussions with clinicians and laboratory workers. Thematic content analyses were performedon qualitative data based on the framework. Descriptive statistical analyses of quantitative data were conducted using Microsoft Excel.Results: Contact between clinicians and laboratory professionals is seldom institutionalised and collaboration is rare. The clinicians believe collaboration with laboratory staff is a challenge because of the gap in education levels. Laboratory workers’ education levels areoften lower than their positions require, leading to clinicians’ lack of respect for and confidencein laboratory professionals, which compromises the laboratory staff’s motivation.Conclusions: Hospital managers, clinicians and laboratory workers need to recognise the critical and complementary roles each professional plays and the importance of addressing the gap between them. Field application of the framework proved successful, justifying the expansion of this study to a larger geographical area to include

  11. Modeling and Testing of EVs - Preliminary Study and Laboratory Development

    DEFF Research Database (Denmark)

    Yang, Guang-Ya; Marra, Francesco; Nielsen, Arne Hejde;

    2010-01-01

    Electric vehicles (EVs) are expected to play a key role in the future energy management system to stabilize both supply and consumption with the presence of high penetration of renewable generation. A reasonably accurate model of battery is a key element for the study of EVs behavior and the grid...... tests, followed by the suggestions towards a feasible battery model for further studies....

  12. Application of Lean-Six Sigma Approach in a Laboratory Experimental Case Study

    Directory of Open Access Journals (Sweden)

    Hashim Raza Rizvi

    2013-12-01

    Full Text Available Laboratory experiments are a conventional activity performed at academic institutions, government and private organizations. These experimental studies provide the basis for new inventions in the field of science and engineering. Laboratory experiments are conducted on the basis of provided guidelines, already established by different standard organizations like ASTM, AASHTO etc. This article is based on a case study in which the process of an experiment is examined on the basis of Value Stream Maps (VSM and potential improvement possibilities have been identified. After determining the potential waste, appropriate Lean tools are selected to implement and observe the improvements. The process is examined after application of the Lean tools and a comparison is performed. University laboratory environment can be improved considerably by applying Lean Tools. MUDA application reduced the total work time from 90.75 hours and 10-CD to 63.75 hours and 7-CD hence saving, 27 hours and 3-CD for one experiment. This is remarkable achievement of this application. Heijunka application provided the students equal workload and they performed explicitly better than they used to. 5-S tool provided the students the opportunity to manage the laboratory in an effective and clean way. Safety of the students is a very major concern at university laboratory environment. 5-S not only upgraded the laboratory overall performance, but it significantly raised the safety standards of the laboratory. More application of the Lean Tools should be exercised explored to have more effective and efficient university laboratory experimental environment.

  13. Scientometric Study of Doctoral Theses of the Physical Research Laboratory

    Science.gov (United States)

    Anilkumar, N.

    2010-10-01

    This paper presents the results of a study of bibliographies compiled from theses submitted in the period 2001-2005. The bibliographies have been studied to find out how research carried out at PRL is being used by the doctoral students. Resources are categorized by type of resource — book, journal article, proceedings, doctoral thesis, etc., to understand the usage of content procured by the library. The period of the study, 2001-2005, has been chosen because technology is changing so fast and so are the formats of scholarly communications. For the sake of convenience, only the "e-journals period" is considered for the sample.

  14. Zero-gravity cloud physics laboratory: Candidate experiments definition and preliminary concept studies

    Science.gov (United States)

    Eaton, L. R.; Greco, R. V.; Hollinden, A. B.

    1973-01-01

    The candidate definition studies on the zero-g cloud physics laboratory are covered. This laboratory will be an independent self-contained shuttle sortie payload. Several critical technology areas have been identified and studied to assure proper consideration in terms of engineering requirements for the final design. Areas include chambers, gas and particle generators, environmental controls, motion controls, change controls, observational techniques, and composition controls. This unique laboratory will allow studies to be performed without mechanical, aerodynamics, electrical, or other type techniques to support the object under study. This report also covers the candidate experiment definitions, chambers and experiment classes, laboratory concepts and plans, special supporting studies, early flight opportunities and payload planning data for overall shuttle payload requirements assessments.

  15. Modeling and Testing of EVs - Preliminary Study and Laboratory Development

    DEFF Research Database (Denmark)

    Yang, Guang-Ya; Marra, Francesco; Nielsen, Arne Hejde

    2010-01-01

    impact at different geographical areas, as well as driving and charging patterns. Electric circuit model is deployed in this work to represent the electrical properties of a lithium-ion battery. This paper reports the preliminary modeling and validation work based on manufacturer data sheet and realistic......Electric vehicles (EVs) are expected to play a key role in the future energy management system to stabilize both supply and consumption with the presence of high penetration of renewable generation. A reasonably accurate model of battery is a key element for the study of EVs behavior and the grid...... tests, followed by the suggestions towards a feasible battery model for further studies....

  16. Progress in glial cell studies in some laboratories in China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Glial cells in the central nervous system(CNS) consist of a heterogeneous population of cell types,each characterized by distinct morphological features,physiological properties,and specific markers.In contrast to the previous view that glial cells were passive elements in the brain,accumulating evidence suggests that glial cells are active participants in various brain functions and brain disorders.This review summarizes recent progress of glial cell studies from several groups in China,ranging from studies about the mechanisms of neuron-glia crosstalking to investigations on the roles of glial cells in various CNS disorders.

  17. Emittances Studies at the Fermilab/NICADD Photoinjector Laboratory

    CERN Document Server

    Tikhoplav, Rodion; Melissinos, A C; Regis-Guy Piot, Philippe

    2005-01-01

    The Fermilab/NICADD photoinjector incorporates an L-band rf-gun capable of generating 1-10 nC bunches. The bunches are then accelerated to 16 MeV with a TESLA superconducting cavity. In the present paper we present parametric studies of transverse emittances and energy spread for a various operating points of the electron source (RF-gun E-field, laser length and spot size, and solenoid settings). We especially study the impact, on transverse emittance, of Gaussian and Plateau temporal distribution of the photocathode drive-laser.

  18. Electric air filtration: theory, laboratory studies, hardware development, and field evaluations

    Energy Technology Data Exchange (ETDEWEB)

    Bergman, W.; Biermann, A.; Kuhl, W.; Lum, B.; Bogdanoff, A.; Hebard, H.; Hall, M.; Banks, D.; Mazumder, M.; Johnson, J.

    1983-09-01

    We summarize the results of a seven-year research project for the US Department of Energy (DOE) to develop electric air filters that extend the service life of high-efficiency particulate air (HEPA) filters used in the nuclear industry. This project was unique to Lawrence Livermore National Laboratory (LLNL), and it entailed comprehensive theory, laboratory studies, and hardware development. We present our work in three major areas: (1) theory of and instrumentation for filter test methods, (2) theoretical and laboratory studies of electric air filters, and (3) development and evaluation of eight experimental electric air filters.

  19. Laboratories for the 21st Century: Case Studies, Molecular Foundry, Berkeley, California

    Energy Technology Data Exchange (ETDEWEB)

    2010-11-01

    This case study provides information on the Molecular Foundry, which incorporates Labs21 principles in its design and construction. The design includes many of the strategies researched at Lawrence Berkeley Laboratory for energy efficient cleanroom and data centers.

  20. Cancer prevention by tea: Evidence from laboratory studies.

    Science.gov (United States)

    Yang, Chung S; Wang, Hong; Li, Guang Xun; Yang, Zhihong; Guan, Fei; Jin, Huanyu

    2011-08-01

    The cancer preventive activities of tea (Camellia sinensis Theaceae) have been studied extensively. Inhibition of tumorigenesis by green tea extracts and tea polyphenols has been demonstrated in different animal models, including those for cancers of the skin, lung, oral cavity, esophagus, stomach, small intestine, colon, bladder, liver, pancreas, prostate, and mammary glands. Many studies in cell lines have demonstrated the modulation of signal transduction and metabolic pathways by (-)-epigallocatechin-3-gallate (EGCG), the most abundant and active polyphenol in green tea. These molecular events can result in cellular changes, such as enhancement of apoptosis, suppression of cell proliferation, and inhibition of angiogenesis. Nevertheless, the molecular mechanisms of inhibition of carcinogenesis in animals and humans remain to be further investigated. Future research directions in this area are discussed.

  1. STUDY OF CLINICAL AND LABORATORY PROFILE OF MALARIA

    Directory of Open Access Journals (Sweden)

    Vishwanath

    2014-11-01

    Full Text Available INTRODUCTION: Malaria is a major health concern across the world and is endemic in our country. It is imperative for us to know the varied manifestations and lab features both classically described and rare features for early detection of this disease and further treatment. This study was undertaken to study the clinical features, lab features and complications of malaria in a tertiary care centre. METHODOLOGY: It is a retrospective study done on 75 cases of confirmed and treated cases of malaria for a period of one year in KIMS hospital, Bangalore. Detailed history examination and lab features of these patients were recorded and analyzed. RESULTS: A total of 75 cases of confirmed malaria were treated during study period of which 57[76%] were males Out of 75 cases 46[61%] had vivax malaria infection, 10[13%] had falciparum infection and 19[26%] had mixed infections of falciparum and vivax. In all 3 groups more number of cases was seen in age group of 18 – 40 years. fever was the major presentation (100% in the patients and Pain abdomen along with fever seen in 15 [20%] patients. Head ache was another predominant complaint in 35[46.6%] On examination Icterus was seen in 11 [14.6%] patients Pallor was seen in 13[17.3%] patients Systolic BP of 2ULN was seen in 9[12%] patients Out of these 6[8%] patients had severe malaria as defined by WHO category of severe malaria. CONCLUSIONS: Being more vigilant and well versed with the varied presentations/lab features of malaria and anticipating complications early, effective treatment can be instituted thus reducing the morbidity and mortality of this endemic disease.

  2. Laboratory studies of paper calendering using a pendulum device

    OpenAIRE

    Hestmo, Rune Harald

    2001-01-01

    The present thesis refers experimental and theoretical studies of the calendering process making use of the pendulum device as a means to simulate the roller calendering. The main task has been to clarify characteristic feature of the device in its capacity to simulate the calendering process with rollers. Measurements are made to enlighten the dependency of the paper characteristics gloss, smoothness and density by the running conditions as nip load, dwell time, roller temperature and moistu...

  3. Oviposition behaviour of Phlebotomus argentipes - A laboratory-based study

    Directory of Open Access Journals (Sweden)

    Vijay Kumar

    2013-12-01

    Full Text Available The breeding habitat of sandflies is a little studied and poorly understood phenomenon. More importantly, oviposition behaviour is a largely neglected aspect of sandfly biology and this knowledge gap further undermines our understanding of the biology of sandflies. Pheromones released by the eggs play an important role in identifying good sites for oviposition by female insects. Several recent studies have examined the oviposition pheromone. The present study provides a preliminary report on the oviposition behaviour of Phlebotomus argentipes, the only vector of kala-azar (or visceral leishmaniasis on the Indian sub-continent. Sandflies prefer to oviposit their eggs on surfaces that contain organic substances, especially substances with an odour of decaying animal products and the remains of conspecific eggs. The results presented here suggest that the odour released by the organic substances of old sandfly colony remains that contain dead flies, old unhatched eggs, larval food containing vertebrate faeces, frass and other organic matter serves as an attractant for the ovipositing females of P. argentipes and hence greatly increases the number of oviposited eggs compared to eggs deposited in controlled oviposition pots. This result will be helpful in maintaining an efficient colony of P. argentipes and may be a promising tool for monitoring and controlling the target insect as part of a synergistic approach.

  4. Laboratory studies of nitrate radical chemistry - application to atmospheric processes

    Energy Technology Data Exchange (ETDEWEB)

    Noremsaune, Ingse

    1997-12-31

    This thesis studies atmospheric chemistry and tries in particular to fill gaps in the data base of atmospheric reactions. It studies the nitrate radical reactions with chloroethenes and with but-2-yne (2-butyne). The mechanisms and rate coefficients for the NO{sub 3}-initiated degradation of the chloroethenes and 2-butyne were investigated by means of the static reaction chamber and the fast flow-discharge technique. The reactions between the nitrate radical and the chloroethenes were studied at atmospheric pressure in a reaction chamber with synthetic air as bath gas. FTIR (Fourier Transform InfraRed spectroscopy) spectroscopy was used to follow the reactions and to identify the products. Products were observed for the reactions with (E)-1,2-dichloroethene and tetrachloroethene, although the absorption bands are weak. The alkyl peroxynitrate and nitrate compounds form very strong and characteristic absorption bands. The rate coefficients for the reactions between NO{sub 3} and the chloroethenes were investigated at room temperature by three different methods. The results are given in tables. 132 refs., 44 figs., 21 tabs.

  5. Laboratory scale studies on removal of chromium from industrial wastes

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Chromium being one of the major toxic pollutants is discharged from electroplating and chrome tanning processes and is also found in the effluents of dyes, paint pigments, manufacturing units etc. Chromium exists in aqueous systems in both trivalent (Cr 3+) and hexavalent (Cr 6+) forms. The hexavalent form is carcinogenic and toxic to aquatic life, whereas Cr3+ is however comparatively less toxic. This study was undertaken to investigate the total chromium removal from industrial effluents by chemical means in order to achieve the Pakistan NEQS level of 1 mg/L by the methods of reduction and precipitation. The study was conducted in four phases.In phase I, the optimum pH and cost effective reducing agent among the four popular commercial chemicals was selected. As a result, pH of 2 was found to be most suitable and sodium meta bisulfate was found to be the most cost effective reducing agent respectively. Phase II showed that lower dose of sodium meta bisulfate was sufficient to obtain 100 % efficiency in reducing Cr6+ to Cr3+, and it was noted that reaction time had no significance in the whole process. A design curve for reduction process was established which can act as a tool for treatment of industrial effluents.Phase III studies indicated the best pH was 8.5 for precipitation of Cr 3+ to chromium hydroxide by using lime. An efficiency of 100 % was achievable and a settling time of 30 minutes produced clear effluent. Finally in Phase IV actual waste samples from chrome tanning and electroplating industries, when precipitated at pH of 12 gave 100 % efficiency at a settling time of 30 minutes and confirmed that chemical means of reduction and precipitation is a feasible and viable solution for treating chromium wastes from industries.

  6. The corrosion of aluminum in dilute solutions: laboratory studies

    Energy Technology Data Exchange (ETDEWEB)

    Draley, J.E.; Arendt, J.W.; English, G.C.; Story, E.F.; Wainscott, M.M.; Berger, R.W.

    1945-06-19

    After it had been decided that aluminum was to be used as a corrosion-resistant material with good heat transfer properties, it was desired to determine the operating conditions to be used in the water-cooled Handford plant in order to avoid danger of corrosion penetration of thin aluminum parts. The studies here reported were undertaken with the object of determining these conditions by investigating the effects of all the known variables which might influence the corrosion behavior of aluminum in a water-coolded plant at HEW. The addition of hydrogen peroxide to the testing solutions was the only effort made to simulate special conditions at the plant.

  7. The corrosion of aluminum in dilute solutions: laboratory studies

    Energy Technology Data Exchange (ETDEWEB)

    Draley, J.E.; Arendt, J.W.; English, G.C.; Story, E.F.; Wainscott, M.M.; Berger, R.W.

    1945-06-19

    After it had been decided that aluminum was to be used as a corrosion-resistant material with good heat transfer properties, it was desired to determine the operating conditions to be used in the water-cooled Handford plant in order to avoid danger of corrosion penetration of thin aluminum parts. The studies here reported were undertaken with the object of determining these conditions by investigating the effects of all the known variables which might influence the corrosion behavior of aluminum in a water-coolded plant at HEW. The addition of hydrogen peroxide to the testing solutions was the only effort made to simulate special conditions at the plant.

  8. Nucleobases in Space: Laboratory Studies of Polycyclic Aromatic Nitrogen Heterocycles

    Science.gov (United States)

    Elsila, Jamie; Mattioda, Andy; Bernstein, Max; Sandford, Scott; Hudgins, Doug

    2005-01-01

    Polycyclic Aromatic Nitrogen Heterocycles (PANHs) are heterocyclic aromatics Le., PAHs with carbon atoms replaced by a nitrogen atom. These molecules have been detected in meteorite extracts, and in general these nitrogen heterocycles are of astrobiological interest since this class of molecules include nucleobases, basic components of our nucleic acids. These compounds are predicted to be present in the interstellar medium and in Titan tholin, but have received relatively little attention. We will present spectra and reactions of PANHs, frozen in solid H2O at 12 K, conditions germane to astronomical observations. In contrast to simple PAHs, that do not interact strongly with solid H2O, the nitrogen atoms in PANHs are potentially capable of hydrogen bonding with H20 changing their spectra, complicating their remote detection on the surfaces of icy bodies. Moreover, we have studied the photo-chemistry of these interesting compounds under astrophysical conditions and will use our lab studies to assess a potential interstellar heritage of these compounds in carbonaceous chondrites.

  9. KETENE FORMATION IN INTERSTELLAR ICES: A LABORATORY STUDY

    Energy Technology Data Exchange (ETDEWEB)

    Hudson, Reggie L.; Loeffler, Mark J., E-mail: Reggie.Hudson@NASA.gov [Astrochemistry Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2013-08-20

    The formation of ketene (H{sub 2}CCO, ethenone) in polar and apolar ices was studied with in situ 0.8 MeV proton irradiation, far-UV photolysis, and infrared spectroscopic analyses at 10-20 K. Using isotopically enriched reagents, unequivocal evidence was obtained for ketene synthesis in H{sub 2}O-rich and CO{sub 2}-rich ices, and several reaction products were identified. Results from scavenging experiments suggested that ketene was formed by free-radical pathways, as opposed to acid-base processes or redox reactions. Finally, we use our results to draw conclusions about the formation and stability of ketene in the interstellar medium.

  10. Laboratory study of methyl isocyanate ices under astrophysical conditions

    Science.gov (United States)

    Maté, B.; Molpeceres, G.; Timón, V.; Tanarro, I.; Escribano, R.; Guillemin, J. C.; Cernicharo, J.; Herrero, V. J.

    2017-10-01

    Methyl isocyanate has been recently detected in comet 67P/Churyumov-Gerasimenko (67P/CG) and in the interstellar medium. New physicochemical studies on this species are now necessary as tools for subsequent studies in astrophysics. In this work, infrared spectra of solid CH3NCO have been obtained at temperatures of relevance for astronomical environments. The spectra are dominated by a strong, characteristic multiplet feature at 2350-2250 cm-1, which can be attributed to the asymmetric stretching of the NCO group. A phase transition from amorphous to crystalline methyl isocyanate is observed at ˜90 K. The band strengths for the absorptions of CH3NCO in ice at 20 K have been measured. Deuterated methyl isocyanate is used to help with the spectral assignment. No X-ray structure has been reported for crystalline CH3NCO. Here we advance a tentative theoretical structure, based on density functional theory (DFT) calculations, derived taking the crystal of isocyanic acid as a starting point. A harmonic theoretical spectrum is then calculated for the proposed structure and compared with the experimental data. A mixed ice of H2O and CH3NCO was formed by simultaneous deposition of water and methyl isocyanate at 20 K. The absence of new spectral features indicates that methyl isocyanate and water do not react appreciably at 20 K, but form a stable mixture. The high CH3NCO/H2O ratio reported for comet 67P/CG, and the characteristic structure of the 2350-2250 cm-1 band, makes it a very good candidate for future astronomical searches.

  11. Preliminary study: Formaldehyde exposure in laboratories of Sharjah university in UAE

    Directory of Open Access Journals (Sweden)

    Hafiz Omer Ahmed

    2011-01-01

    Full Text Available Objectives : Laboratory technicians, students, and instructors are at high risk, because they deal with chemicals including formaldehyde. Thus, this preliminary study was conducted to measure the concentration of formaldehyde in the laboratories of the University of Sharjah in UAE. Materials and Methods: Thirty-two air samples were collected and analyzed for formaldehyde using National Institute for Occupational Safety and Health (NIOSH method 3500. In this method, formaldehyde reacts with chromotropic acid in the presence of sulfuric acid to form a colored solution. The absorbance of the colored solution is read in spectrophotometer at wavelength 580 nm and is proportional to the quantity of the formaldehyde in the solution. Results: For the anatomy laboratory and in the presence of the covered cadaver, the mean concentration of formaldehyde was found to be 0.100 ppm with a range of 0.095-0.105 ppm. Whereas for the other laboratories, the highest mean concentration of formaldehyde was 0.024 ppm in the general microbiology laboratory and the lowest mean concentration of formaldehyde was 0.001 ppm in the environmental health laboratory. The 8-hour (time-weighted average concentration of formaldehyde was found to be ranging between 0.0003 ppm in environmental health laboratory and 0.026 ppm in the anatomy laboratory. Conclusions: The highest level of concentration of formaldehyde in the presence of the covered cadaver in anatomy laboratory exceeded the recommended ceiling standard established by USA-NIOSH which is 0.1 ppm, but below the ceiling standard established by American Conference of Governmental Industrial Hygienists which is 0.3 ppm. Thus, it is recommended that formaldehyde levels should be measured periodically specially during the dissection in the anatomy laboratory, and local exhaust ventilation system should be installed and personal protective equipment such as safety glass and gloves should be available and be used to prevent

  12. Detection of Cryptosporidium and Giardia in clinical laboratories in Europe--a comparative study.

    Science.gov (United States)

    Manser, M; Granlund, M; Edwards, H; Saez, A; Petersen, E; Evengard, B; Chiodini, P

    2014-01-01

    To determine the routine diagnostic methods used and compare the performance in detection of oocysts of Cryptosporidium species and cysts of Giardia intestinalis in faecal samples by European specialist parasitology laboratories and European clinical laboratories. Two sets of seven formalin-preserved faecal samples, one containing cysts of Giardia intestinalis and the other, containing oocysts of Cryptosporidium, were sent to 18 laboratories. Participants were asked to examine the specimens using their routine protocol for detecting these parasites and state the method(s) used. Eighteen laboratories answered the questionnaire. For detection of Giardia, 16 of them used sedimentation/concentration followed by light microscopy. Using this technique the lower limit of detection of Giardia was 17.2 cysts/mL of faeces in the best performing laboratories. Only three of 16 laboratories used fluorescent-conjugated antibody-based microscopy. For detection of Cryptosporidium acid-fast staining was used by 14 of the 17 laboratories that examined the samples. With this technique the lower limit of detection was 976 oocysts/mL of faeces. Fluorescent-conjugated antibody-based microscopy was used by only five of the 17 laboratories. There was variation in the lower limit of detection of cysts of Giardia and oocysts of Cryptosporidium between laboratories using the same basic microscopic methods. Fluorescent-conjugated antibody-based microscopy was not superior to light microscopy under the conditions of this study. There is a need for a larger-scale multi-site comparison of the methods used for the diagnosis of these parasites and the development of a Europe-wide laboratory protocol based upon its findings.

  13. Clinical and laboratorial study of 19 cases of mucopolysaccharidoses

    Directory of Open Access Journals (Sweden)

    Albano Lilian M. J.

    2000-01-01

    Full Text Available The mucopolysaccharidoses (MPS are a heterogeneous group of inborn errors of lysosomal glycosaminoglycan (GAG metabolism. The importance of this group of disorders among the inborn errors of metabolism led us to report 19 cases. METHOD: We performed clinical, radiological, and biochemical evaluations of the suspected patients, which allowed us to establish a definite diagnosis in 19 cases. RESULTS: Not all patients showed increased GAG levels in urine; enzyme assays should be performed in all cases with strong clinical suspicion. The diagnosis was made on average at the age of 48 months, and the 19 MPS cases, after a full clinical, radiological, and biochemical study, were classified as follows: Hurler -- MPS I (1 case; Hunter -- MPS II (2 cases; Sanfilippo -- MPS III (2 cases; Morquio -- MPS IV (4 cases; Maroteaux-Lamy -- MPS VI (9 cases; and Sly -- MPS VII (1 case. DISCUSSION: The high relative frequency of Maroteaux-Lamy disease contrasts with most reports in the literature and could express a population variability.

  14. Gas migration through cement slurries analysis: A comparative laboratory study

    Directory of Open Access Journals (Sweden)

    Arian Velayati

    2015-12-01

    Full Text Available Cementing is an essential part of every drilling operation. Protection of the wellbore from formation fluid invasion is one of the primary tasks of a cement job. Failure in this task results in catastrophic events, such as blow outs. Hence, in order to save the well and avoid risky and operationally difficult remedial cementing, slurry must be optimized to be resistant against gas migration phenomenon. In this paper, performances of the conventional slurries facing gas invasion were reviewed and compared with modified slurry containing special gas migration additive by using fluid migration analyzer device. The results of this study reveal the importance of proper additive utilization in slurry formulations. The rate of gas flow through the slurry in neat cement is very high; by using different types of additives, we observe obvious changes in the performance of the cement system. The rate of gas flow in neat class H cement was reported as 36000 ml/hr while the optimized cement formulation with anti-gas migration and thixotropic agents showed a gas flow rate of 13.8 ml/hr.

  15. Laboratory Studies on the Effects of Shear on Fish

    Energy Technology Data Exchange (ETDEWEB)

    Neitzel, Duane A.; Richmond, Marshall C.; Dauble, Dennis D.; Mueller, Robert P.; Moursund, Russell A.; Abernethy, Cary S.; Guensch, Greg R.

    2000-09-20

    The overall objective of our studies was to specify an index describing the hydraulic force that fish experience when subjected to a shear environment. Fluid shear is a phenomenon that is important to fish. However, elevated levels of shear may result in strain rates that injure or kill fish. At hydroelectric generating facilities, concerns have been expressed that strain rates associated with passage through turbines, spillways, and fish bypass systems may adversely affect migrating fish. Development of fish friendly hydroelectric turbines requires knowledge of the physical forces (injury mechanisms) that impact entrained fish and the fish's tolerance to these forces. It requires up-front, pre-design specifications for the environmental conditions that occur within the turbine system, in other words, determining or assuming that those conditions known to injure fish will provide the descriptions of conditions that engineers must consider in the design of a turbine system. These biological specifications must be carefully and thoroughly documented throughout the design of a fish friendly turbine. To address the development of biological specifications, we designed and built a test facility where juvenile fish could be subjected to a range of shear environments and quantified their biological response.

  16. A Depth Estimation System for Laboratory Studies using Video Imagery

    Directory of Open Access Journals (Sweden)

    A Torres

    2008-01-01

    Full Text Available A simple video-based system has been developed for depth estimation based on wave propagation characteristics. A numerical simulation of a long-crested monochromatic wave propagating over a beach with straight and parallel contours is used for testing the depth inversion system. An oblique video, simulating field conditions, is recorded, digitized and rectified for its further analysis. Pixel intensity time series from a virtual array in the rectified images are analyzed using the depth estimation technique developed by Stockdon and Holman. The linear dispersion equation is applied for depth estimation at every cross-shore position and the resulting values are compared with the depth values used to feed the numerical model. Error analysis confirms good performance for depth estimation using this video-system for completely controlled conditions in small-scale experiments. The relative depth estimation error for this idealized case is 2.3%. This accuracy is explained by the use of a linear model for the wave propagation simulation. The methodology proposed here allows the testing of a new video-system and separation of errors resulting from the depth inversion algorithm from those inherent to photogrammetry techniques in small areas. The use of this system could easily be extended for physical models and field studies.

  17. Inter-laboratory comparison study for pyrrolizidine alkaloids in animal feed using spiked and incurred material.

    Science.gov (United States)

    de Nijs, Monique; Elbers, Ingrid J W; Mulder, Patrick P J

    2014-01-01

    Pyrrolizidine alkaloids (PAs) are hepatotoxic metabolites produced by plants. PAs in animal feed can cause acute or chronic intoxications in animals and can be transferred to milk. An inter-laboratory comparison study among 12 laboratories, using their own methods of analysis, was conducted for the detection and quantification of PAs in animal feed. The participants were asked to quantify PAs in a blank test sample, a blank test sample to be spiked with a provided spiking mixture of seven PA standards, and a test sample contaminated with common groundsel (Senecio vulgaris). Ten of the participating laboratories used an LC-MS/MS method, one used an LC-ToF-MS method, and one used a GC-MS method. None of the laboratories reported false-negative samples, while two laboratories reported false-positive results in the blank sample. z-scores were calculated for each laboratory for seven PAs in test samples B and C. z-scores varied considerably between laboratories for the concentrations of the free bases and less for the N-oxides, probably due to the lower levels of the free bases as compared with the N-oxides in the contaminated feed. Questionable or unsatisfactory results for the z-scores were obtained for 8% of the cases for the spiked sample and for 12% of the incurred sample. Three laboratories scored consequently positive or negative results. No preferred method for quantification of PAs in feed could be identified within the methods used for this study due to the relatively small number of participants. It was concluded that this inter-laboratory study shows that the methods used for PA detection need further development for accurate estimation of PAs in contaminated feed.

  18. [The external evaluation of study quality: the role in maintaining the reliability of laboratory information].

    Science.gov (United States)

    Men'shikov, V V

    2013-08-01

    The external evaluation of quality of clinical laboratory examinations was gradually introduced in USSR medical laboratories since 1970s. In Russia, in the middle of 1990 a unified all-national system of external evaluation quality was organized known as the Federal center of external evaluation of quality at the basis of laboratory of the state research center of preventive medicine. The main positions of policy in this area were neatly formulated in the guidance documents of ministry of Health. Nowadays, the center of external evaluation of quality proposes 100 and more types of control studies and permanently extends their specter starting from interests of different disciplines of clinical medicine. The consistent participation of laboratories in the cycles of external evaluation of quality intrinsically promotes improvement of indicators of properness and precision of analysis results and increases reliability of laboratory information. However, a significant percentage of laboratories does not participate at all in external evaluation of quality or takes part in control process irregularly and in limited number of tests. The managers of a number of medical organizations disregard the application of the proposed possibilities to increase reliability of laboratory information and limit financing of studies in the field of quality control. The article proposes to adopt the national standard on the basis of ISO 17043 "Evaluation of compliance. The common requirements of professional competence testing".

  19. Nitrogen limited biobarriers remove atrazine from contaminated water: Laboratory studies

    Science.gov (United States)

    Hunter, William J.; Shaner, Dale L.

    2009-01-01

    Atrazine is one of the most frequently used herbicides. This usage coupled with its mobility and recalcitrant nature in deeper soils and aquifers makes it a frequently encountered groundwater contaminant. We formed biobarriers in sand filled columns by coating the sand with soybean oil; after which, we inoculated the barriers with a consortium of atrazine-degrading microorganisms and evaluated the ability of the barriers to remove atrazine from a simulated groundwater containing 1 mg L - 1 atrazine. The soybean oil provided a carbon rich and nitrogen poor substrate to the microbial consortium. Under these nitrogen-limiting conditions it was hypothesized that bacteria capable of using atrazine as a source of nitrogen would remove atrazine from the flowing water. Our hypothesis proved correct and the biobarriers were effective at removing atrazine when the nitrogen content of the influent water was low. Levels of atrazine in the biobarrier effluents declined with time and by the 24th week of the study no detectable atrazine was present (limit of detection atrazine were also removed by the biobarriers; when biobarriers were fed 16.3 mg L - 1 atrazine 97% was degraded. When nitrate (5 mg L - 1 N), an alternate source of nitrogen, was added to the influent water the atrazine removal efficiency of the barriers was reduced by almost 60%. This result supports the hypothesis that atrazine was degraded as a source of nitrogen. Poisoning of the biobarriers with mercury chloride resulted in an immediate and large increase in the amount of atrazine in the barrier effluents confirming that biological activity and not abiotic factors were responsible for most of the atrazine degradation. The presence of hydroxyatrazine in the barrier effluents indicated that dehalogenation was one of the pathways of atrazine degradation. Permeable barriers might be formed in-situ by the injection of innocuous vegetable oil emulsions into an aquifer or sandy soil and used to remove atrazine from a

  20. Laboratory study of avalanches in a magnetized plasma

    Science.gov (United States)

    van Compernolle, Bart

    2015-11-01

    Results of a basic heat transport experiment [] involving an off-axis heat source are presented. Experiments are performed in the Large Plasma Device (LAPD) at UCLA. A ring-shaped electron beam source injects low energy electrons (below ionization energy) along a strong magnetic field into a preexisting, large and cold plasma. The injected electrons are thermalized by Coulomb collisions within a short distance and provide an off-axis heat source that results in a long, hollow, cylindrical region of elevated electron temperature embedded in a colder plasma, and far from the machine walls. It is demonstrated that this heating configuration provides an ideal environment to study avalanche phenomena under controlled conditions. The avalanches are identified as sudden rearrangements of the pressure profile following the growth of fluctuations from ambient noise. The intermittent collapses of the plasma pressure profile are associated with unstable drift-Alfvén waves and exhibit both radial and azimuthal dynamics. After each collapse the plasma enters a quiescent phase in which the pressure profile slowly recovers and steepens until a threshold is exceeded, and the process repeats. The use of reference probes as time markers allows for the visualization of the 2D spatio-temporal evolution of the avalanche events. Avalanches are only observed for a limited combination of heating powers and magnetic fields. At higher heating powers the system transitions from the avalanche regime into a regime dominated by sustained drift-Alfvén wave activity. The pressure profile then transitions to a near steady-state in which anomalous transport balances the external pressure source. Performed at the Basic Plasma Science Facility at UCLA, supported jointly by DOE and NSF.

  1. Nitrogen limited biobarriers remove atrazine from contaminated water: laboratory studies.

    Science.gov (United States)

    Hunter, William J; Shaner, Dale L

    2009-01-07

    Atrazine is one of the most frequently used herbicides. This usage coupled with its mobility and recalcitrant nature in deeper soils and aquifers makes it a frequently encountered groundwater contaminant. We formed biobarriers in sand filled columns by coating the sand with soybean oil; after which, we inoculated the barriers with a consortium of atrazine-degrading microorganisms and evaluated the ability of the barriers to remove atrazine from a simulated groundwater containing 1 mg L(-1) atrazine. The soybean oil provided a carbon rich and nitrogen poor substrate to the microbial consortium. Under these nitrogen-limiting conditions it was hypothesized that bacteria capable of using atrazine as a source of nitrogen would remove atrazine from the flowing water. Our hypothesis proved correct and the biobarriers were effective at removing atrazine when the nitrogen content of the influent water was low. Levels of atrazine in the biobarrier effluents declined with time and by the 24th week of the study no detectable atrazine was present (limit of detectionwater the atrazine removal efficiency of the barriers was reduced by almost 60%. This result supports the hypothesis that atrazine was degraded as a source of nitrogen. Poisoning of the biobarriers with mercury chloride resulted in an immediate and large increase in the amount of atrazine in the barrier effluents confirming that biological activity and not abiotic factors were responsible for most of the atrazine degradation. The presence of hydroxyatrazine in the barrier effluents indicated that dehalogenation was one of the pathways of atrazine degradation. Permeable barriers might be formed in-situ by the injection of innocuous vegetable oil emulsions into an aquifer or sandy soil and used to remove atrazine from a contaminated groundwater or to protect groundwater from an atrazine spill.

  2. The Study Of Clinical And Laboratory Finding In Wheat Allergy

    Directory of Open Access Journals (Sweden)

    Farhoodi. A

    2002-07-01

    Full Text Available Food allergy is affecting 6-8 percent of infants. Wheat is major source of carbohydrate and protein in the people's nutrition in all worlds and also account for one of six main food allergens in children. The goal of this study is diagnosis of wheat allergic patients and description of its importance for better recognition of this disease."nMaterials and Methods: Among children with different symptoms of allergy (dermatologic - Gastro intestinal and respiratory symptoms referred to Immunology and allergy Department of Markaz Tebbi Kodakan, during one year, 35 cases was suspected to have wheat allergy. Skin prick test and IgE specific with wheat for all of them and open food challenge test with wheat for 11 patients without history of anaphylaxy were done. The criteria for diagnosis was based on a convincing history of anaphylaxis after ingestion of wheat or the positive result in food challenge with wheat in addition to positive skin prick test ( SPT or specific IgE ( Eliza with wheat."nResults: In 35 suspected cases to wheat allergy, SPT in 85/1 percent, specific IgE in 90/3 percent were positive. Food challenge test were done in 11 cases and was positive in 27/2 percent of patients. 24 patients were definitely diagnosed as wheat allergic ones. Anaphylaxis was the predominant clinical feature, accounted for 87 percent of acute symptoms which were repeated for two or more episode in 91 percent of the cases with anaphylaxis. In 50 percent of patients chronic symptoms like asthma and atopic dermatitis were also observed."nConclusion: The mean age of symptom was compatible with time of onset of complementary foods. Therefore, were proposed exclusive breastfeeding without maternal avoidance and not to be introducing wheat in infant regimen until 12 mouth of age. Anaphylaxis was occurred, repeatedly in these patients which demonstrate, in one part, severity of the reactions in our patients and in other part the probable existence of more cases

  3. Comparison of microbiological diagnosis of urinary tract infection in young children by routine health service laboratories and a research laboratory: Diagnostic cohort study

    Science.gov (United States)

    Birnie, Kate; Hay, Alastair D.; Wootton, Mandy; Howe, Robin; MacGowan, Alasdair; Whiting, Penny; Lawton, Michael; Delaney, Brendan; Downing, Harriet; Dudley, Jan; Hollingworth, William; Lisles, Catherine; Little, Paul; O’Brien, Kathryn; Pickles, Timothy; Rumsby, Kate; Thomas-Jones, Emma; Van der Voort, Judith; Waldron, Cherry-Ann; Harman, Kim; Hood, Kerenza; Butler, Christopher C.; Sterne, Jonathan A. C.

    2017-01-01

    Objectives To compare the validity of diagnosis of urinary tract infection (UTI) through urine culture between samples processed in routine health service laboratories and those processed in a research laboratory. Population and methods We conducted a prospective diagnostic cohort study in 4808 acutely ill children aged <5 years attending UK primary health care. UTI, defined as pure/predominant growth ≥105 CFU/mL of a uropathogen (the reference standard), was diagnosed at routine health service laboratories and a central research laboratory by culture of urine samples. We calculated areas under the receiver-operator curve (AUC) for UTI predicted by pre-specified symptoms, signs and dipstick test results (the “index test”), separately according to whether samples were obtained by clean catch or nappy (diaper) pads. Results 251 (5.2%) and 88 (1.8%) children were classified as UTI positive by health service and research laboratories respectively. Agreement between laboratories was moderate (kappa = 0.36; 95% confidence interval [CI] 0.29, 0.43), and better for clean catch (0.54; 0.45, 0.63) than nappy pad samples (0.20; 0.12, 0.28). In clean catch samples, the AUC was lower for health service laboratories (AUC = 0.75; 95% CI 0.69, 0.80) than the research laboratory (0.86; 0.79, 0.92). Values of AUC were lower in nappy pad samples (0.65 [0.61, 0.70] and 0.79 [0.70, 0.88] for health service and research laboratory positivity, respectively) than clean catch samples. Conclusions The agreement of microbiological diagnosis of UTI comparing routine health service laboratories with a research laboratory was moderate for clean catch samples and poor for nappy pad samples and reliability is lower for nappy pad than for clean catch samples. Positive results from the research laboratory appear more likely to reflect real UTIs than those from routine health service laboratories, many of which (particularly from nappy pad samples) could be due to contamination. Health service

  4. Chemistry Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: To conduct fundamental studies of highway materials aimed at understanding both failure mechanisms and superior performance. New standard test methods are...

  5. Maintaining turbidity and current flow in laboratory aquarium studies, a case study using Sabellaria spinulosa

    DEFF Research Database (Denmark)

    Davies, Andrew J.; S. Last, Kim; Attard, Karl

    2009-01-01

    Many aquatic organisms rely on the suspension of particulate matter for food or for building materials, yet these conditions are difficult to replicate in laboratory mesocosms. Consequently, husbandry and experimental conditions may often be sub-optimal. The Vortex Resuspension Tank (Vo......RT) is a simple and reliable system for the resuspension of food or sediments using an enclosed airlift. The particle rain from the lift is mixed in the tank by two water inputs that provide directional current flow across the study organism(s). The vortex mixing creates a turbulent lateral water flow that allows...... whereas under intermediate and high sediment rates there was consistent cumulative growth throughout a 15 d experiment. This highlights the importance of suspended sediment for S. spinulosa and also the suitability of the VoRT system for maintaining organisms with suspended matter requirements....

  6. Studying Human Disease Genes in "Caenorhabditis Elegans": A Molecular Genetics Laboratory Project

    Science.gov (United States)

    Cox-Paulson, Elisabeth A.; Grana, Theresa M.; Harris, Michelle A.; Batzli, Janet M.

    2012-01-01

    Scientists routinely integrate information from various channels to explore topics under study. We designed a 4-wk undergraduate laboratory module that used a multifaceted approach to study a question in molecular genetics. Specifically, students investigated whether "Caenorhabditis elegans" can be a useful model system for studying genes…

  7. Studying Human Disease Genes in "Caenorhabditis Elegans": A Molecular Genetics Laboratory Project

    Science.gov (United States)

    Cox-Paulson, Elisabeth A.; Grana, Theresa M.; Harris, Michelle A.; Batzli, Janet M.

    2012-01-01

    Scientists routinely integrate information from various channels to explore topics under study. We designed a 4-wk undergraduate laboratory module that used a multifaceted approach to study a question in molecular genetics. Specifically, students investigated whether "Caenorhabditis elegans" can be a useful model system for studying genes…

  8. Variability of Creatinine Measurements in Clinical Laboratories: Results from the CRIC Study

    Science.gov (United States)

    Joffe, Marshall; Hsu, Chi-yuan; Feldman, Harold I.; Weir, Matthew; Landis, J.R.; Hamm, L. Lee

    2010-01-01

    Objectives Estimating equations using serum creatinine (SCr) are often used to assess glomerular filtration rate (GFR). Such creatinine (Cr)-based formulae may produce biased estimates of GFR when using Cr measurements that have not been calibrated to reference laboratories. In this paper, we sought to examine the degree of this variation in Cr assays in several laboratories associated with academic medical centers affiliated with the Chronic Renal Insufficiency Cohort (CRIC) Study; to consider how best to correct for this variation, and to quantify the impact of such corrections on eligibility for participation in CRIC. Variability of Cr is of particular concern in the conduct of CRIC, a large multicenter study of subjects with chronic renal disease, because eligibility for the study depends on Cr-based assessment of GFR. Methods A library of 5 large volume plasma specimens from apheresis patients was assembled, representing levels of plasma Cr from 0.8 to 2.4 mg/dl. Samples from this library were used for measurement of Cr at each of the 14 CRIC laboratories repetitively over time. We used graphical displays and linear regression methods to examine the variability in Cr, and used linear regression to develop calibration equations. We also examined the impact of the various calibration equations on the proportion of subjects screened as potential participants who were actually eligible for the study. Results There was substantial variability in Cr assays across laboratories and over time. We developed calibration equations for each laboratory; these equations varied substantially among laboratories and somewhat over time in some laboratories. The laboratory site contributed the most to variability (51% of the variance unexplained by the specimen) and variation with time accounted for another 15%. In some laboratories, calibration equations resulted in differences in eligibility for CRIC of as much as 20%. Conclusions The substantial variability in SCr assays

  9. Past and Future Work on Radiobiology Mega-Studies: A Case Study At Argonne National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Haley, Benjamin; Wang, Qiong; Wanzer, Beau; Vogt, Stefan; Finney, Lydia; Yang, Ping Liu; Paunesku, Tatjana; Woloschak, Gayle

    2011-09-06

    Between 1952 and 1992, more than 200 large radiobiology studies were conducted in research institutes throughout Europe, North America, and Japan to determine the effects of external irradiation and internal emitters on the lifespan and tissue toxicity development in animals. At Argonne National Laboratory, 22 external beam studies were conducted on nearly 700 beagle dogs and 50,000 mice between 1969 and 1992. These studies helped to characterize the effects of neutron and gamma irradiation on lifespan, tumorigenesis, and mutagenesis across a range of doses and dosing patterns. The records and tissues collected at Argonne during that time period have been carefully preserved and redisseminated. Using these archived data, ongoing statistical work has been done and continues to characterize quality of radiation, dose, dose rate, tissue, and gender-specific differences in the radiation responses of exposed animals. The ongoing application of newly-developed molecular biology techniques to the archived tissues has revealed gene-specific mutation rates following exposure to ionizing irradiation. The original and ongoing work with this tissue archive is presented here as a case study of a more general trend in the radiobiology megastudies. These experiments helped form the modern understanding of radiation responses in animals and continue to inform development of new radiation models. Recent archival efforts have facilitated open access to the data and materials produced by these studies, and so a unique opportunity exists to expand this continued research.

  10. Laboratory Spectroscopy of Large Carbon Molecules and Ions in Support of Space Missions. A New Generation of Laboratory & Space Studies

    Science.gov (United States)

    Salama, Farid; Tan, Xiaofeng; Cami, Jan; Biennier, Ludovic; Remy, Jerome

    2006-01-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are an important and ubiquitous component of carbon-bearing materials in space. A long-standing and major challenge for laboratory astrophysics has been to measure the spectra of large carbon molecules in laboratory environments that mimic (in a realistic way) the physical conditions that are associated with the interstellar emission and absorption regions [1]. This objective has been identified as one of the critical Laboratory Astrophysics objectives to optimize the data return from space missions [2]. An extensive laboratory program has been developed to assess the properties of PAHs in such environments and to describe how they influence the radiation and energy balance in space. We present and discuss the gas-phase electronic absorption spectra of neutral and ionized PAHs measured in the UV-Visible-NIR range in astrophysically relevant environments and discuss the implications for astrophysics [1]. The harsh physical conditions of the interstellar medium characterized by a low temperature, an absence of collisions and strong VUV radiation fields - have been simulated in the laboratory by associating a pulsed cavity ringdown spectrometer (CRDS) with a supersonic slit jet seeded with PAHs and an ionizing, penning-type, electronic discharge. We have measured for the {\\it first time} the spectra of a series of neutral [3,4] and ionized [5,6] interstellar PAHs analogs in the laboratory. An effort has also been attempted to quantify the mechanisms of ion and carbon nanoparticles production in the free jet expansion and to model our simulation of the diffuse interstellar medium in the laboratory [7]. These experiments provide {\\it unique} information on the spectra of free, large carbon-containing molecules and ions in the gas phase. We are now, for the first time, in the position to directly compare laboratory spectral data on free, cold, PAH ions and carbon nano-sized carbon particles with astronomical observations in the

  11. Water quality laboratories in Colombia: a GIS-based study of urban and rural accessibility.

    Science.gov (United States)

    Wright, Jim; Liu, Jing; Bain, Robert; Perez, Andrea; Crocker, Jonny; Bartram, Jamie; Gundry, Stephen

    2014-07-01

    The objective of this study was to quantify sample transportation times associated with mandated microbiological monitoring of drinking-water in Colombia. World Health Organization Guidelines for Drinking-Water Quality recommend that samples spend no more than 6h between collection and analysis in a laboratory. Census data were used to estimate the minimum number of operational and surveillance samples required from piped water supplies under national regulations. Drive-times were then computed from each supply system to the nearest accredited laboratory and translated into sample holding times based on likely daily monitoring patterns. Of 62,502 surveillance samples required annually, 5694 (9.1%) were found to be more than 6 h from the nearest of 278 accredited laboratories. 612 samples (1.0%) were more than 24 hours' drive from the nearest accredited laboratory, the maximum sample holding time recommended by the World Health Organization. An estimated 30% of required rural samples would have to be stored for more than 6 h before reaching a laboratory. The analysis demonstrates the difficulty of undertaking microbiological monitoring in rural areas and small towns from a fixed laboratory network. Our GIS-based approach could be adapted to optimise monitoring strategies and support planning of testing and transportation infra-structure development. It could also be used to estimate sample transport and holding times in other countries.

  12. Addressing the key communication barriers between microbiology laboratories and clinical units: a qualitative study.

    Science.gov (United States)

    Skodvin, Brita; Aase, Karina; Brekken, Anita Løvås; Charani, Esmita; Lindemann, Paul Christoffer; Smith, Ingrid

    2017-09-01

    Many countries are on the brink of establishing antibiotic stewardship programmes in hospitals nationwide. In a previous study we found that communication between microbiology laboratories and clinical units is a barrier to implementing efficient antibiotic stewardship programmes in Norway. We have now addressed the key communication barriers between microbiology laboratories and clinical units from a laboratory point of view. Qualitative semi-structured interviews were conducted with 18 employees (managers, doctors and technicians) from six diverse Norwegian microbiological laboratories, representing all four regional health authorities. Interviews were recorded and transcribed verbatim. Thematic analysis was applied, identifying emergent themes, subthemes and corresponding descriptions. The main barrier to communication is disruption involving specimen logistics, information on request forms, verbal reporting of test results and information transfer between poorly integrated IT systems. Furthermore, communication is challenged by lack of insight into each other's area of expertise and limited provision of laboratory services, leading to prolonged turnaround time, limited advisory services and restricted opening hours. Communication between microbiology laboratories and clinical units can be improved by a review of testing processes, educational programmes to increase insights into the other's area of expertise, an evaluation of work tasks and expansion of rapid and point-of-care test services. Antibiotic stewardship programmes may serve as a valuable framework to establish these measures.

  13. A cross-laboratory preclinical study on the effectiveness of interleukin-1 receptor antagonist in stroke.

    Science.gov (United States)

    Maysami, Samaneh; Wong, Raymond; Pradillo, Jesus M; Denes, Adam; Dhungana, Hiramani; Malm, Tarja; Koistinaho, Jari; Orset, Cyrille; Rahman, Mahbubur; Rubio, Marina; Schwaninger, Markus; Vivien, Denis; Bath, Philip M; Rothwell, Nancy J; Allan, Stuart M

    2016-03-01

    Stroke represents a global challenge and is a leading cause of permanent disability worldwide. Despite much effort, translation of research findings to clinical benefit has not yet been successful. Failure of neuroprotection trials is considered, in part, due to the low quality of preclinical studies, low level of reproducibility across different laboratories and that stroke co-morbidities have not been fully considered in experimental models. More rigorous testing of new drug candidates in different experimental models of stroke and initiation of preclinical cross-laboratory studies have been suggested as ways to improve translation. However, to our knowledge, no drugs currently in clinical stroke trials have been investigated in preclinical cross-laboratory studies. The cytokine interleukin 1 is a key mediator of neuronal injury, and the naturally occurring interleukin 1 receptor antagonist has been reported as beneficial in experimental studies of stroke. In the present paper, we report on a preclinical cross-laboratory stroke trial designed to investigate the efficacy of interleukin 1 receptor antagonist in different research laboratories across Europe. Our results strongly support the therapeutic potential of interleukin 1 receptor antagonist in experimental stroke and provide further evidence that interleukin 1 receptor antagonist should be evaluated in more extensive clinical stroke trials.

  14. Laboratories for the 21st Century: Case Studies; National Renewable Energy Laboratory, Science and Technology Facility, Golden, Colorado (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    Van Geet, O.

    2010-04-01

    As a Laboratories for the 21st Century (Labs21) partner, NREL set aggressive goals for energy savings, daylighting, and achieving a LEED Gold rating (through the U.S. Green Building Council's Leadership in Energy and Environmental Design program) for its S&TF building.

  15. LABORATORY STUDIES ON THE STABILITY AND TRANSPORT OF INORGANIC COLLOIDS THROUGH NATURAL AQUIFER MATERIAL

    Science.gov (United States)

    The stability and transport of radio-labeled Fe2O3 particles were studied using laboratory batch and column techniques. Core material collected from shallow sand and gravel aquifer was used as the immobile column matrix material. Variables in the study included flow rate, pH, i...

  16. Out of the Laboratory and Down to the Bay: Writing in Science and Technology Studies.

    Science.gov (United States)

    Myers, Greg

    1996-01-01

    Offers a personal view of some developments in science and technology studies. Argues that the field has emerged from laboratory studies to engagement with broader issues of power and change. Explains that frameworks developed in the sociology of scientific knowledge have been applied to the analysis of things, of social boundaries, and of…

  17. Use of the LITEE Lorn Manufacturing Case Study in a Senior Chemical Engineering Unit Operations Laboratory

    Science.gov (United States)

    Abraham, Nithin Susan; Abulencia, James Patrick

    2011-01-01

    This study focuses on the effectiveness of incorporating the Laboratory for Innovative Technology and Engineering Education (LITEE) Lorn Manufacturing case into a senior level chemical engineering unit operations course at Manhattan College. The purpose of using the case study is to demonstrate the relevance of ethics to chemical engineering…

  18. Design of a mobile laboratory for ventilation studies and indoor air pollution monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Berk, J.V.; Hollowell, C.D.; Lin, C.I.; Pepper, J.H.

    1978-04-01

    The design and fabrication of a mobile laboratory for research and development studies of ventilation requirements and energy utilization in residential and commercial buildings are described. Functionality, flexibility, and versatility have been stressed without sacrificing appearance and operator convenience. It is believed that modifications of and additions to the mobile laboratory (such as adding the capability to monitor building energy flow) can be made with a minimum of inconvenience. The studies being performed will provide data needed for the establishment of energy efficient ventilation standards.

  19. Large excavations and multi-disciplinary studies in deep underground laboratories

    Directory of Open Access Journals (Sweden)

    Wang Joseph S.Y.

    2014-01-01

    Full Text Available Since 2013, we have gathered some information on excavations recently completed, renovated, or planned in Asia, Europe, North and South America. In this review, we presented what we learned on both the large excavations and on multi-disciplinary studies. Large excavations in physics laboratories are driven by the needs associated with designing next generation of experiments to detect rare events. Some existing physics laboratories are interested to use available spaces for geo-sciences studies, including microbiological research for deep life. Summary of recent progress will be discussed.

  20. Developing an Attitude Scale towards Physics Laboratory: A Study on Validity and Reliability

    Directory of Open Access Journals (Sweden)

    Gülşah TANRIVERDİ

    2012-12-01

    Full Text Available The aim of the study is to reveal the results of a validity and reliability study for the attitude scale which is developed to assess the attitudes of first-year undergraduates in Teacher Training in Sciences department towards physics laboratories. At the first step of the study, students who attended Physics Laboratory-I course were asked for their views about physics laboratories. The first items of the scale on attitude were created in parallel to the teacher candidates’ views. The experimental group of the study consists of 118 primary school teacher candidate students at Faculty of Education in Kırıkkale University. As a result of the study on validity and reliability 27 attitude scale items were created 21 of which were positive and 6 of which were negative. This resulting attitude scale with 27 items was called "Attitude Scale Towards Physics Laboratories" (ASCTPL. Having made the factor analysis it was seen that the ASCTPL had 6 factors at total. The dimensions of these 6 factors were "Methods and Techniques Applied during the Course","Teacher's Attitude towards the Course", "Technical Opportunities in the Laboratories", "Associating the Course with Daily Life", "Students' Personal Attitudes towards the Course" and "Field Knowledge". The variant that the whole of the scale expressed was 59,143%, and Cornbach-Alpha coefficient of internal consistency was estimated α = 0,90. Considering the results, it can be concluded that the scale is both valid and reliable. Also, this five point Likert-type scale can be used to determine the attitudes of students at Teacher Training in Sciences department towards the physics laboratories.

  1. INDICATORS OF UNCERTAINTY FOR THE DECISIONS OF ARCHITECTURE TO LABORATORIES NB3 – STUDY OF CASES

    Directory of Open Access Journals (Sweden)

    Valéria Michielin VIEIRA

    2008-11-01

    Full Text Available In the design of biological research laboratories that deal with pathogens, the architect must incorporate aspects related to other disciplines, considering that the quality of those environments is related to biosafety concept. In order to meet the biosafety guidelines, the project coordinator must attempt to the compatibility among different requirements which are associated to the performance level expected in this kind of facility. Aiming to examine how biosafety guidelines have been incorporated in the design of laboratories that require biosafety level three (BSL3 it was developed a study of cases of facilities using post-occupancy evaluation methods. Through the post-occupancy evaluation it was possible to establish the state of the art of BSL3 laboratories in use in Brazil. The search for indicators of laboratories design proved that some architecture decisions are not constrained by biosafety guidelines. The study was conducted with the intention to contribute for the development of future projects. Key words: biosafety, post-occupancy evaluation, laboratories design.

  2. Behavioural risk factors in two generations of non-Western migrants: do trends converge towards the host population?

    Science.gov (United States)

    Hosper, Karen; Nierkens, Vera; Nicolaou, Mary; Stronks, Karien

    2007-01-01

    Migrant mortality does not conform to a single pattern of convergence towards prevalence rates in the host population. To understand better how migrant mortality develops, it is necessary to further investigate how the underlying behavioural determinants change following migration. We studied whether the prevalence of behavioural risk factors over two generations of Turkish and Moroccan migrants converge towards the prevalence rates in the Dutch population. From a random sample from the population register of Amsterdam, 291 Moroccan and 505 Turkish migrants, aged 15-30, participated in a structured interview that included questions on smoking, alcohol consumption, physical inactivity and weight/height. Data from the Dutch population were available from Statistics Netherlands. By calculating age-adjusted Odds Ratio's, prevalence rates among both generations were compared with prevalence rates in the host population for men and women separately. We found indications of convergence across generations towards the prevalence rates in the host population for smoking in Turkish men, for overweight in Turkish and Moroccan women and for physical inactivity in Turkish women. Alcohol consumption, however, remained low in all subgroups and did not converge towards the higher rates in the host population. In addition, we found a reversed trend among Turkish women regarding smoking: the second generation smoked significantly more, while the first generation did not differ from ethnic Dutch. In general, behavioural risk factors in two generations of non-Western migrants in the Netherlands seem to converge towards the prevalence rates in the Dutch population. However, some subgroups and risk factors showed a different pattern.

  3. Variability in baseline laboratory measurements of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

    Science.gov (United States)

    Ladwig, R; Vigo, A; Fedeli, L M G; Chambless, L E; Bensenor, I; Schmidt, M I; Vidigal, P G; Castilhos, C D; Duncan, B B

    2016-08-01

    Multi-center epidemiological studies must ascertain that their measurements are accurate and reliable. For laboratory measurements, reliability can be assessed through investigation of reproducibility of measurements in the same individual. In this paper, we present results from the quality control analysis of the baseline laboratory measurements from the ELSA-Brasil study. The study enrolled 15,105 civil servants at 6 research centers in 3 regions of Brazil between 2008-2010, with multiple biochemical analytes being measured at a central laboratory. Quality control was ascertained through standard laboratory evaluation of intra- and inter-assay variability and test-retest analysis in a subset of randomly chosen participants. An additional sample of urine or blood was collected from these participants, and these samples were handled in the same manner as the original ones, locally and at the central laboratory. Reliability was assessed with the intraclass correlation coefficient (ICC), estimated through a random effects model. Coefficients of variation (CV) and Bland-Altman plots were additionally used to assess measurement variability. Laboratory intra and inter-assay CVs varied from 0.86% to 7.77%. From test-retest analyses, the ICCs were high for the majority of the analytes. Notably lower ICCs were observed for serum sodium (ICC=0.50; 95%CI=0.31-0.65) and serum potassium (ICC=0.73; 95%CI=0.60-0.83), due to the small biological range of these analytes. The CVs ranged from 1 to 14%. The Bland-Altman plots confirmed these results. The quality control analyses showed that the collection, processing and measurement protocols utilized in the ELSA-Brasil produced reliable biochemical measurements.

  4. The study of the thermal neutron flux in the deep underground laboratory DULB-4900

    CERN Document Server

    Gavrilyuk, Yu M; Gezhaev, A M; Kazalov, V V; Kuzminov, V V; Panasenko, S I; Ratkevich, S S; Tekueva, D A; Yakimenko, S P

    2015-01-01

    We report on the study of thermal neutron flux using monitors based on mixture of ZnS(Ag) and LiF enriched with a lithium-6 isotope at the deep underground laboratory DULB-4900 at the Baksan Neutrino Observatory. An annual modulation of thermal neutron flux in DULB-4900 is observed. Experimental evidences were obtained of correlation between the long-term thermal neutron flux variations and the absolute humidity of the air in laboratory. The amplitude of the modulation exceed 5\\% of total neutron flux flux.

  5. Subjective interpretation, laboratory error and the value of forensic DNA evidence: three case studies.

    Science.gov (United States)

    Thompson, W C

    1995-01-01

    This article discusses two factors that may profoundly affect the value of DNA evidence for proving that two samples have a common source: uncertainty about the interpretation of test results and the possibility of laboratory error. Three case studies are presented to illustrate the importance of the analyst's subjective judgments in interpreting some RFLP-based forensic DNA tests. In each case, the likelihood ratio describing the value of DNA evidence is shown to be dramatically reduced by uncertainty about the scoring of bands and the possibility of laboratory error. The article concludes that statistical estimates of the frequency of matching genotypes can be a misleading index of the value of DNA evidence, and that more adequate indices are needed. It also argues that forensic laboratories should comply with the National Research Council's recommendation that forensic test results be scored in a blind or objective manner.

  6. A FMEA clinical laboratory case study: how to make problems and improvements measurable.

    Science.gov (United States)

    Capunzo, Mario; Cavallo, Pierpaolo; Boccia, Giovanni; Brunetti, Luigi; Pizzuti, Sante

    2004-01-01

    The authors have experimented the application of the Failure Mode and Effect Analysis (FMEA) technique in a clinical laboratory. FMEA technique allows: a) to evaluate and measure the hazards of a process malfunction, b) to decide where to execute improvement actions, and c) to measure the outcome of those actions. A small sample of analytes has been studied: there have been determined the causes of the possible malfunctions of the analytical process, calculating the risk probability index (RPI), with a value between 1 and 1,000. Only for the cases of RPI > 400, improvement actions have been implemented that allowed a reduction of RPI values between 25% to 70% with a costs increment of FMEA technique can be applied to the processes of a clinical laboratory, even if of small dimensions, and offers a high potential of improvement. Nevertheless, such activity needs a thorough planning because it is complex, even if the laboratory already operates an ISO 9000 Quality Management System.

  7. Disordered Silicates in Space: a Study of Laboratory Spectra of "Amorphous" Silicates

    CERN Document Server

    Speck, Angela K; Hofmeister, Anne M

    2011-01-01

    We present a laboratory study of silicate glasses of astrophysically relevant compositions including olivines, pyroxenes and melilites. With emphasis on the classic Si-O stretching feature near 10 microns, we compare infrared spectra of our new samples with laboratory spectra on ostensibly similar compositions, and also with synthetic silicate spectral data commonly used in dust modeling. Several different factors affect spectral features including sample chemistry (e.g., polymerization, Mg/Fe ratio, oxidation state and Al-content) and different sample preparation techniques lead to variations in porosity, density and water content. The convolution of chemical and physical effects makes it difficult to attribute changes in spectral parameters to any given variable. It is important that detailed chemical and structural characterization be provided along with laboratory spectra. In addition to composition and density, we measured the glass transition temperatures for the samples which place upper limits on the ...

  8. Fire vs. Metal: A Laboratory Study Demonstrating Microbial Responses to Soil Disturbances

    Science.gov (United States)

    Stromberger, Mary E.

    2005-01-01

    Incubation studies are traditionally used in soil microbiology laboratory classes to demonstrate microbial respiration and N mineralization-immobilization processes. Sometimes these exercises are done to calculate a N balance in N fertilizer-amended soils. However, examining microbial responses to environmental perturbations would appeal to soil…

  9. Particle in a Disk: A Spectroscopic and Computational Laboratory Exercise Studying the Polycyclic Aromatic Hydrocarbon Corannulene

    Science.gov (United States)

    Frey, E. Ramsey; Sygula, Andrzej; Hammer, Nathan I.

    2014-01-01

    This laboratory exercise introduces undergraduate chemistry majors to the spectroscopic and theoretical study of the polycyclic aromatic hydrocarbon (PAH), corannulene. Students explore the spectroscopic properties of corannulene using UV-vis and Raman vibrational spectroscopies. They compare their experimental results to simulated vibrational…

  10. Laboratory animal allergy : allergen exposure assessment and epidemiological study of risk factors

    NARCIS (Netherlands)

    Hollander, A.

    1997-01-01

    The main objective of the study presented in this thesis was to estimate the prevalence rate of laboratory animal allergy and to determine its association with risk factors, like allergen exposure level, atopy, gender and other host factors. A cross-sectional survey was undertaken among 540

  11. Cardiopulmonary imaging, functional and laboratory studies in sickle cell disease associated pulmonary hypertension

    NARCIS (Netherlands)

    van Beers, Eduard J.; Nur, Erfan; Schaefer-Prokop, Cornelia M.; Mac Gillavry, Melvin R.; van Esser, Joost W. J.; Brandjes, Dees P. M.; Kappers-Klunne, Maria C.; Duits, Ashley J.; Muskiet, Frits A. J.; Schnog, John-John B.; Biemond, Bart J.

    2008-01-01

    Pulmonary hypertension (PHT) occurs in approximately 30% of adults with sickle cell disease (SCD) and is an independent risk factor for early death. In this study, we aimed to determine the value of general laboratory testing, plain chest radiography, electrocardiography (ECG), high-resolution compu

  12. Particle in a Disk: A Spectroscopic and Computational Laboratory Exercise Studying the Polycyclic Aromatic Hydrocarbon Corannulene

    Science.gov (United States)

    Frey, E. Ramsey; Sygula, Andrzej; Hammer, Nathan I.

    2014-01-01

    This laboratory exercise introduces undergraduate chemistry majors to the spectroscopic and theoretical study of the polycyclic aromatic hydrocarbon (PAH), corannulene. Students explore the spectroscopic properties of corannulene using UV-vis and Raman vibrational spectroscopies. They compare their experimental results to simulated vibrational…

  13. An Evaluation of Outcomes Following the Replacement of Traditional Histology Laboratories with Self-Study Modules

    Science.gov (United States)

    Thompson, Andrew R.; Lowrie, Donald J., Jr.

    2017-01-01

    Changes in medical school curricula often require educators to develop teaching strategies that decrease contact hours while maintaining effective pedagogical methods. When faced with this challenge, faculty at the University of Cincinnati College of Medicine converted the majority of in-person histology laboratory sessions to self-study modules…

  14. On the atmospheric chemistry of NO2 - O3 systems; a laboratory study.

    NARCIS (Netherlands)

    Verhees, P.W.C.

    1986-01-01

    In this dissertation a laboratory study dealing with the atmospheric chemistry of NO 2 -O 3 systems is described. Knowledge of this system is relevant for a better understanding of a number of air pollution problems, particularly th

  15. Experimental Study of Drag Resistance using a Laboratory Scale Rotary Set-Up

    DEFF Research Database (Denmark)

    Weinell, Claus Erik; Olsen, Kenneth N.; Christoffersen, Martin W.;

    2003-01-01

    This work covers an experimental study of the drag resistance of different painted surfaces and simulated large-scale irregularities, viz. dry spraying, weld seams, barnacle fouling and paint remains. A laboratory scale rotary set-up was used to determine the drag resistance, and the surface...

  16. An ECVAG inter-laboratory validation study of the comet assay

    DEFF Research Database (Denmark)

    Ersson, Clara; Møller, Peter; Forchhammer, Lykke

    2013-01-01

    The alkaline comet assay is an established, sensitive method extensively used in biomonitoring studies. This method can be modified to measure a range of different types of DNA damage. However, considerable differences in the protocols used by different research groups affect the inter-laboratory...

  17. An ECVAG inter-laboratory validation study of the comet assay: inter-laboratory and intra-laboratory variations of DNA strand breaks and FPG-sensitive sites in human mononuclear cells.

    Science.gov (United States)

    Ersson, Clara; Møller, Peter; Forchhammer, Lykke; Loft, Steffen; Azqueta, Amaya; Godschalk, Roger W L; van Schooten, Frederik-Jan; Jones, George D D; Higgins, Jennifer A; Cooke, Marcus S; Mistry, Vilas; Karbaschi, Mahsa; Phillips, David H; Sozeri, Osman; Routledge, Michael N; Nelson-Smith, Kirsty; Riso, Patrizia; Porrini, Marisa; Matullo, Giuseppe; Allione, Alessandra; Stepnik, Maciej; Ferlińska, Magdalena; Teixeira, João Paulo; Costa, Solange; Corcuera, Laura-Ana; López de Cerain, Adela; Laffon, Blanca; Valdiglesias, Vanessa; Collins, Andrew R; Möller, Lennart

    2013-05-01

    The alkaline comet assay is an established, sensitive method extensively used in biomonitoring studies. This method can be modified to measure a range of different types of DNA damage. However, considerable differences in the protocols used by different research groups affect the inter-laboratory comparisons of results. The aim of this study was to assess the inter-laboratory, intra-laboratory, sample and residual (unexplained) variations in DNA strand breaks and formamidopyrimidine DNA glycosylase (FPG)-sensitive sites measured by the comet assay by using a balanced Latin square design. Fourteen participating laboratories used their own comet assay protocols to measure the level of DNA strand breaks and FPG-sensitive sites in coded samples containing peripheral blood mononuclear cells (PBMC) and the level of DNA strand breaks in coded calibration curve samples (cells exposed to different doses of ionising radiation) on three different days of analysis. Eleven laboratories found dose-response relationships in the coded calibration curve samples on two or three days of analysis, whereas three laboratories had technical problems in their assay. In the coded calibration curve samples, the dose of ionising radiation, inter-laboratory variation, intra-laboratory variation and residual variation contributed to 60.9, 19.4, 0.1 and 19.5%, respectively, of the total variation. In the coded PBMC samples, the inter-laboratory variation explained the largest fraction of the overall variation of DNA strand breaks (79.2%) and the residual variation (19.9%) was much larger than the intra-laboratory (0.3%) and inter-subject (0.5%) variation. The same partitioning of the overall variation of FPG-sensitive sites in the PBMC samples indicated that the inter-laboratory variation was the strongest contributor (56.7%), whereas the residual (42.9%), intra-laboratory (0.2%) and inter-subject (0.3%) variations again contributed less to the overall variation. The results suggest that the

  18. The Reproducibility of Changes in Diagnostic Figures of Merit Across Laboratory and Clinical Imaging Reader Studies.

    Science.gov (United States)

    Samuelson, Frank W; Abbey, Craig K

    2017-06-27

    In this paper we examine which comparisons of reading performance between diagnostic imaging systems made in controlled retrospective laboratory studies may be representative of what we observe in later clinical studies. The change in a meaningful diagnostic figure of merit between two diagnostic modalities should be qualitatively or quantitatively comparable across all kinds of studies. In this meta-study we examine the reproducibility of relative measures of sensitivity, false positive fraction (FPF), area under the receiver operating characteristic (ROC) curve, and expected utility across laboratory and observational clinical studies for several different breast imaging modalities, including screen film mammography, digital mammography, breast tomosynthesis, and ultrasound. Across studies of all types, the changes in the FPFs yielded very small probabilities of having a common mean value. The probabilities of relative sensitivity being the same across ultrasound and tomosynthesis studies were low. No evidence was found for different mean values of relative area under the ROC curve or relative expected utility within any of the study sets. The comparison demonstrates that the ratios of areas under the ROC curve and expected utilities are reproducible across laboratory and clinical studies, whereas sensitivity and FPF are not. Published by Elsevier Inc.

  19. Rethinking anti-smoking media campaigns: two generations of research and issues for the next.

    Science.gov (United States)

    Logan, R A; Longo, D R

    1999-01-01

    This article provides a variety of alternative theoretical issues and new research directions for smoking media campaign research. The first two generations of smoking media campaign research are reviewed and new ideas about public resistance and resolving complex issues are explored. The authors critique the limits of current campaign theory and their premise that how the public resolves issues such as smoking cessation needs to be seen in a broader context. The consciousness raising, working through, and resolution stages each present a series of different research challenges and issues for investigators. These are: (1) an assessment of the perceived credibility by the target audience toward mass media, news media, health care providers, tobacco firms, area health care agencies, the health care delivery system, and different classes of providers, (2) how smokers and nonsmokers differ on the linkage among biomedical, epidemiological, and toxicological controversies, (3) how smoking issues are managed within arenas, (4) how arenas potentially undermine popular participation in public policy formation, and (5) how in the creation of dialogue there should be dual emphases on the viability of the concept and tactics.

  20. Growth regression models at two generations of selected populations Alabio ducks

    Directory of Open Access Journals (Sweden)

    L Hardi Prasetyo

    2007-12-01

    Full Text Available A selection process to increase egg production of Alabio ducks was conducted in Balai Penelitian Ternak, Ciawi-Bogor. The selection aimed at increasing production, however observation on growth of the selected ducks was necessary since early growth stage (0-8 wks determines the performance during laying period. This paper presents the growth models and the coefficient of determination of two generations of selected Alabio ducks. Body weight were observed weekly on 363 ducks from F1 and 356 ducks from F2, between 0-8 weeks and then fortinghly until 16 weeks. Growth curves were analysed using regression models between age and bodyweight of each population. The selection of model with the best fit was based on the large value of determination coefficient (R2, small value of MSE, and sinificant level of regression coefficient. Result showed that cubic polynomial regression was the best fit for the two populations, Y = 56.31-1.44X+0.64X2-0.005X3 for F1 and Y = 43.05 + 0.96X + 0.69X2 - 0.0056X3 for F2. The values of R2 were 0.9466 for F1 and 0.9243 for F2, and the values of MSE were 11.586 for F1 and 19.978 for F2. The growth of F1 is better during starter period, but F2 is better during grower period.

  1. Understanding the Migratory Orientation Program of Birds: Extending Laboratory Studies to Study Free-Flying Migrants in a Natural Setting

    DEFF Research Database (Denmark)

    Thorup, Kasper; Holland, R.A.; Tøttrup, Anders Peter Them;

    2010-01-01

    orient during migration. Despite the difficulties associated with following free-flying birds over long distances, a number of possibilities currently exist for tracking the long distance, sometimes even globe-spanning, journeys undertaken by migrating birds. Birds fitted with radio transmitters can...... behaviors that are otherwise very difficult to study. Here, we focus on the progress in understanding certain components of the migration-orientation system. Comparably exciting results can be expected in the future from tracking free-flying migrants in the wild. Use of orientation cues has been studied......For many years, orientation in migratory birds has primarily been studied in the laboratory. Although a laboratory-based setting enables greater control over environmental cues, the laboratory-based findings must be confirmed in the wild in free-flying birds to be able to fully understand how birds...

  2. Electromagnetic Investigations and Power Converter Efficiency Studies on a Laboratory Made Induction Heating Prototype

    Science.gov (United States)

    Roy, M.; Sengupta, M.

    2013-09-01

    In this paper electromagnetic analysis and power converter efficiency has been studied on a laboratory prototype induction heating coil. An electromagnetic field based study was first done for the induction heating coil used in the experimental set-up using available Finite Element Analysis package software (FEMM 4.2). The results of the FEM based study are also used in the choice of the operating frequency depending on the applications. Thereafter verifications are done experimentally on a small-scale laboratory developed setup. The approach to be adopted for choice of induction heating operating frequency and the choice of converter type, based on the efficiency and performance, are also briefly presented here. Oscilloscope traces uphold the accuracy of the practical tests conducted.

  3. Laboratory Astrophysics Studies with the COSmIC Facility: Interstellar and Planetary Applications.

    Science.gov (United States)

    Salama, Farid; Contreras, Cesar S.; Sciamma-O'Brien, Ella; Bejaoui, Salma

    2015-08-01

    We present and discuss the characteristics and the capabilities of the laboratory facility, COSmIC, that was developed at NASA Ames to generate, process and analyze interstellar, circumstellar and planetary analogs in the laboratory [1]. COSmIC stands for “Cosmic Simulation Chamber” and is dedicated to the study of neutral and ionized molecules and nano particles under the low temperature and high vacuum conditions that are required to simulate space environments. COSmIC integrates a variety of state-of-the-art instruments that allow forming, processing and monitoring simulated space conditions for planetary, circumstellar and interstellar materials in the laboratory. COSmIC is composed of a Pulsed Discharge Nozzle (PDN) expansion that generates a plasma in free supersonic jet expansion coupled to two high-sensitivity, complementary in situ diagnostics: a Cavity Ring Down Spectroscopy (CRDS) and laser induced fluorescence (LIF) systems for photonic detection and a Reflectron Time-Of-Flight Mass Spectrometer (ReTOF-MS) for mass detection [2].Recent laboratory astrophysics results that were obtained using COSmIC will be presented, in particular the progress that has been achieved in the domain of the diffuse interstellar bands (DIBs) and in monitoring, in the laboratory, the formation of dust grains and aerosols from their gas-phase molecular precursors in environments as varied as stellar/circumstellar outflows [3] and planetary atmospheres [4]. Plans for future, next generation, laboratory experiments on cosmic molecules and grains in the growing field of laboratory astrophysics will also be addressed as well as the implications of the current studies for astronomy.References:[1] Salama F., In Organic Matter in Space, IAU Symposium 251, Kwok & Sandford Eds.Cambridge University Press, Vol. 4, S251, p. 357 (2008) and references therein.[2] Ricketts C., Contreras C., Walker, R., Salama F., Int. J. Mass Spec, 300, 26 (2011)[3] Cesar Contreras and Farid Salama, The

  4. Time study of clinical and nonclinical workload in pathology and laboratory medicine.

    Science.gov (United States)

    Trotter, Martin J; Larsen, Erik T; Tait, Nicholas; Wright, James R

    2009-06-01

    We describe a detailed, cross-sectional, self-report time study of laboratory physician tasks in a regionalized, multisite academic setting, using custom data collection templates programmed into personal digital assistants (PDAs). The 7-week study was completed by 56 medical and scientific staff (86% participation rate). Participants recorded 12,781 PDA entries of specific tasks completed during the study period. The mean number of entries per worked day per participant was 8.14 (range, 1.96-14.33). Study results demonstrated that professional staff worked, on average, 53.5 hours per week. Percentage work time spent in each activity area was as follows: clinical, direct, 50.6%; administration, 18.5%; clinical, indirect, 9.5%; research, 8.2%; learning/continuing education, 5.3%; teaching, 4.9%; and quality assurance, 3.1%. These percentages varied significantly by laboratory medicine subspecialty and by type of academic appointment. The findings confirm that activities not directly involved with patient care, such as administration, quality assurance, teaching, research, and professional development, typically occupy 40% to 50% of a laboratory physician's time.

  5. Studies of high energy density physics and laboratory astrophysics driven by intense lasers

    Science.gov (United States)

    Zhang, J.

    2016-10-01

    Laser plasmas are capable of creating unique physical conditions with extreme high energy density, which are not only closely relevant to inertial fusion energy studies, but also to laboratory simulation of some astrophysical processes. In this paper, we highlight some recent progress made by our research teams. The first part is about directional hot electron beam generation and transport for fast ignition of inertial confinement fusion, as well as a new scheme of fast ignition by use of a strong external DC magnetic field. The second part concerns laboratory modeling of some astrophysical phenomena, including 1) studies of the topological structure of magnetic reconnection/annihilation that relates closely to geomagnetic substorms, loop-top X-ray source and mass ejection in solar flares, and 2) magnetic field generation and evolution in collisionless shock formation.

  6. Study of embryotoxic effects of intranasally administred desloratadine on laboratory animals

    Directory of Open Access Journals (Sweden)

    Alekhina Т.А.

    2017-04-01

    Full Text Available The study was conducted to detect possible changes in embryogenesis and negative effects of third generation antihistamine – desloratadine – after intranasal administration of 1.3 mg/m3 and 13.0 mg/m3 of the substance to laboratory animals during their prenatal period. In these circumstances, desloratadine does not cause any significant changes of embryogenesis parameters. Macroscopic examination of the fetus and placenta in animals of experimental groups did not reveal any pathology or physiological deviations from the norm. 13.0 mg/m3 concentration of the drug caused a decrease in the weight of embryos in comparison with control group of animals and physiological data, despite a well developed, without visible pathology, placenta. This neces­sitates an in-depth study of possible teratogenic effects of intranasally administred desloratadine to laboratory animals.

  7. Using ecology to inform physiology studies: implications of high population density in the laboratory.

    Science.gov (United States)

    Newman, Amy E M; Edmunds, Nicholas B; Ferraro, Shannon; Heffell, Quentin; Merritt, Gillian M; Pakkala, Jesse J; Schilling, Cory R; Schorno, Sarah

    2015-03-15

    Conspecific density is widely recognized as an important ecological factor across the animal kingdom; however, the physiological impacts are less thoroughly described. In fact, population density is rarely mentioned as a factor in physiological studies on captive animals and, when it is infrequently addressed, the animals used are reared and housed at densities far above those in nature, making the translation of results from the laboratory to natural systems difficult. We survey the literature to highlight this important ecophysiological gap and bring attention to the possibility that conspecific density prior to experimentation may be a critical factor influencing results. Across three taxa: mammals, birds, and fish, we present evidence from ecology that density influences glucocorticoid levels, immune function, and body condition with the intention of stimulating discussion and increasing consideration of population density in physiology studies. We conclude with several directives to improve the applicability of insights gained in the laboratory to organisms in the natural environment.

  8. The Role of Heterogeneous Chemistry of Volatile ORganic Compounds: A Modeling and Laboratory Study

    Energy Technology Data Exchange (ETDEWEB)

    Gregory R. Carmichael; Vicki H. Grassian

    2007-03-01

    Overview The outputs of this research have been reported annually via the RIMS system. This report serves as an update and final report. The focus of our DOE BES funded project is on the importance of heterogeneous reactions in the troposphere. The primary objectives of our study were to: (i) Evaluate the extent to which heterogeneous chemistry affects the photochemical oxidant cycle, particularly, sources and sinks of tropospheric ozone; and (ii) Conduct laboratory studies on heterogeneous reactions involving NOy, O3 and VOCs on aerosol surfaces. These objectives were pursued through a multidisciplinary approach that combines modeling and laboratory components as discussed in more detail below. In addition, in response to the reconfiguring of the Atmospheric Science Program to focus on aerosol radiative forcing of climate, we also began to investigate the radiative properties of atmospheric aerosol.

  9. Photochemical Activity of Aldrin and Dieldrin in Liquid and Frozen Aqueous Systems: Field and Laboratory Studies

    Science.gov (United States)

    Bausch, A. R.; Rowland, G. A.; Grannas, A. M.

    2008-12-01

    The phenomenon of global distillation generates significant accumulation of volatile, anthropogenic persistent organic pollutants (POPs) in polar regions. Bioaccumulation presents serious concerns for human health within Arctic subsistence communities. In the recent past, the photochemical processes of POPs have been observed in the laboratory. Despite some established knowledge regarding photochemical processes in reactive frozen media, little published literature exists regarding the chemical transformations and fate of POPs in the Arctic. Here, we consider the photochemical transformations of aldrin and dieldrin, two structurally similar organochlorine pollutants whose presence has been confirmed in the Arctic. Their photochemical transformation, resulting from ultraviolet exposure, was investigated by both field studies in Barrow, AK and controlled laboratory experiments. Pollutant degradation and photoproduct formation were monitored by GC-ECD analysis. Based on kinetic studies of liquid and frozen samples and identification of photoproducts, we will propose potential reaction mechanisms for the transformations of aldrin and dieldrin. Further implications for environmental processes will be discussed.

  10. Laboratory experiments in the study of the chemistry of the outer planets

    Science.gov (United States)

    Scattergood, T. W.

    It is shown that much information about planetary chemistry and physics can be gained through laboratory work. The types of experiments relevant to planetary research concern fundamental properties, spectral/optical properties, 'Miller-Urey' syntheses, and detailed syntheses. Specific examples of studies of the chemistry in the atmosphere of Titan are described with attention given to gas phase chemistry in the troposphere and the composition of model Titan aerosols. A list of work that still needs to be done is provided.

  11. A cross-laboratory preclinical study on the effectiveness of interleukin-1 receptor antagonist in stroke

    OpenAIRE

    2015-01-01

    Stroke represents a global challenge and is a leading cause of permanent disability worldwide. Despite much effort, translation of research findings to clinical benefit has not yet been successful. Failure of neuroprotection trials is considered, in part, due to the low quality of preclinical studies, low level of reproducibility across different laboratories and that stroke co-morbidities have not been fully considered in experimental models. More rigorous testing of new drug candidates in d...

  12. Preventing Long-Term Risk of Obesity for Two Generations: Prenatal Physical Activity Is Part of the Puzzle

    Directory of Open Access Journals (Sweden)

    Stephanie-May Ruchat

    2012-01-01

    Full Text Available Background. The period surrounding pregnancy has been identified as a risk period for overweight/obesity in both mother and child because of excessive gestational weight gain (GWG. The promotion of a healthy GWG is therefore of paramount importance in the context of the prevention of obesity in the current and next generations. Objective. To provide a comprehensive overview of the effect of prenatal physical activity interventions, alone or in combination with nutritional counselling, on GWG and to address whether preventing excessive GWG decreases the incidence of infant high birth weight and/or postpartum weight retention. Method. A search of the PubMed database was conducted to identify all relevant studies. Nineteen studies were included in this review: 13 interventions combining physical activity, nutrition, and GWG counselling and 6 interventions including physical activity alone. Results. Prenatal lifestyle interventions promoting healthy eating and physical activity habits appear to be the most effective approach to prevent excessive GWG. Achievement of appropriate GWG may also decrease the incidence of high infant birth weight and postpartum weight retention. Conclusion. Healthy eating habits during pregnancy, combined with an active lifestyle, may be important elements in the prevention of long-term risk of obesity for two generations.

  13. Biodemographic and sociocultural factors in two generations of families from six Polish rural and urban populations.

    Science.gov (United States)

    Wolański, N

    1994-01-01

    There were investigated 6967 families from 6 rural regions, under industrialization, and industrialized urban regions. In the grandparents generation there were taken into account 10 traits (an education level, a mating radius, and a stature) and in parents generation 17 traits (the mentioned-above ones and a number of family members, a flat size, incomes, an employees No., a life mode, smoking etc. Numerical characteristics of traits have been calculated jointly and separately in six populations, matrices of correlation have been constructed and moreover factorial analysis have been carried out, as a result of which 8 rotated factors have been obtained. The highest cultural mobility (increase in the level of education) from generation to generation occurs in the population of textile industry town Lódź. The highest improvement of biological status, the increase in mating radius and high incomes are characteristic for this regions, too. On the other side are villages with low culture mobility (not large increase in education level), slight improvement of biological status, almost no migrations, overcrowded flats and low income per family member. The relations between pairs of traits appear to vary largely in several populations. Generally is a high correlation between the education level of the same family members in both generations. The has been stated negative correlation between grandfather stature both of the mother and the father lines, with occurring of positive assortative mating in the couples of two generations. In both investigated generations there is the positive assortative mating, but the negative correlation in the stature between grandfathers of the mother and the father lines. The grandparents education level is correlated with their and their offsprings stature. The duration of holidays is one of the best (closely correlated with others) indicators of life mode, and partially of a given family living conditions, too. 8 hidden factors have been

  14. A comparison of a biological sciences curriculum study (BSCS) laboratory and a traditional laboratory on student achievement at two private liberal arts colleges

    Science.gov (United States)

    Hall, Donald A.; McCurdy, Donald W.

    The purpose of this experiment was to compare an inquiry-oriented Biological Sciences Curriculum Study (BSCS) style laboratory approach with a more directive traditional approach on student outcomes in the cognitive and affective domains of learning at two private, midwestern liberal-arts colleges. The BSCS approach emphasized basic and integrated science processes, concept development through extensive questioning, and increased student discretion, while the traditional approach contained highly structured, more prescriptive, teacher-oriented activities. Intact laboratory sections of students enrolled in introductory general biology at two private liberal-arts colleges were randomly selected into two treatment groups. Pretest and posttest measures were taken on three dependent variables: (1) biological content achievement, measured with a researcher-generated Test on Biology Laboratory Concepts, (2) reasoning ability, measured with the Group Assessment of Logical Thinking, and (3) attitude toward biology, measured with the Biology Student Behavior Inventory. Analysis of covariance indicated the experimental group (n = 60) using the BSCS-style laboratory approach scored significantly higher than the comparison group (n = 59) in levels of performance on biology content achievement, F(1, 114) = 4.07, p attitude toward biology or on reasoning ability. However, both groups experienced a 15-percent increase in the number of formal thinkers as indicated by pretest-posttest gain scores on the reasoning ability test. These results lend support to the hypothesis that a BSCS-style laboratory approach fosters desired learner outcomes at the postsecondary level. In addition, these findings support the notion that the science laboratory may be used as a primary vehicle to promote formal reasoning skills.

  15. Pre-operative laboratory testing: A prospective study on comparison and cost analysis

    Directory of Open Access Journals (Sweden)

    Venkatesh H Keshavan

    2016-01-01

    Full Text Available Background and Aims : Pre-operative investigations are performed before any surgical intervention under anaesthesia. Many are considered as routine. However, there are no clear guidelines regarding these in India. We aim to look at the relevance of the laboratory investigations ordered routinely and their cost implications compared with the National Institute of Clinical Excellence (NICE guidelines. Methods: This prospective study was carried out at a tertiary care hospital. A total of 163 patients scheduled for elective surgical procedures were included in this study. Neither the surgeons nor anaesthesiologists involved in the case were aware of the study. The laboratory investigations of the patients who underwent surgery were noted. All values were categorised as normal or abnormal and they were assessed as indicated or unindicated based on NICE guidelines. Results: One hundred and sixty-three patients were subjected to a total of 984 tests. Forty three patients (26% were subjected to tests as per NICE guidelines. Of the 984 tests, 515 tests were unindicated (52%. Out of the 515 unindicated tests, 7 (1.3% were abnormal. None of these seven tests required any intervention or change of anaesthetic plan. The most common unindicated tests done were cardiac echocardiography and chest X-ray (92.5% and 93% respectively. The additional cost incurred towards unindicated tests was 63% of the total cost for the tests. Conclusion: Pre-operative laboratory investigations add to cost significantly. Patient premorbid conditions and surgical grade should guide the clinician to request for the relevant laboratory tests.

  16. Service Quality and Patient Satisfaction: An Exploratory Study of Pathology Laboratories in Jaipur.

    Science.gov (United States)

    Agarwal, Anuradha; Singh, Maithili R P

    2016-01-01

    One of the most important parts of healthcare system is diagnostics. Nowadays, Indians have become more aware of their health, due to improved and better availability of health related information, increase in medical tourism, and expanding health insurance. The demand for better diagnostic facilities have increased with the increase in lifestyle related diseases, excesses use of chemicals in agriculture practices and change in food habits. It is expected that the Indian diagnostic market will grow from USD $5 billion in the year 2012 to USD $32 billion by the year 2020 with 20% CAGR (India Brand Equity Foundation 2015 ). Today patients have easy access of information regarding the health services and they have become more concerned about it as they look forward to receiving the maximum value for their money. To win the confidence of the patients and to maintain that trust, it is required to deliver the right services to the right person at the right time. The purpose of this study was to develop a scale to measure the service quality at pathology laboratory. A thorough review of literature revealed that there are studies related to healthcare service quality but there is no such established scale to measure service quality of pathology laboratory. Thus, the authors strived to develop a reliable and valid instrument to measure the patients' perception toward pathology laboratory service quality. For this exploratory study was conducted on the sample of 80 patients of the laboratories in Jaipur city. The reliability and factor structures were tested to purify the scale. The findings revealed 13 items, comprising of three dimensions of service quality: responsiveness, tangibility, and reliability.

  17. DHM and serious games: a case-study oil and gas laboratories.

    Science.gov (United States)

    Santos, V; Zamberlan, M; Streit, P; Oliveira, J; Guimarães, C; Pastura, F; Cid, G

    2012-01-01

    The aim in this paper is to present a research on the application of serious games for the design of laboratories in the oil and gas industries. The focus is in human virtual representation acquired from 3D scanning, human interaction, workspace layout and equipment designed considering ergonomics standards. The laboratory studies were simulated in Unity3D platform, which allows the users to control the DHM1 on the dynamic virtual scenario, in order to simulate work activities. This methodology can change the design process by improving the level of interaction between final users, managers and human factor teams. That helps to better visualize future work settings and improve the level of participation between all stakeholders.

  18. The Study of Indicatrices of Space Object Coatings in a Controlled Laboratory Environment

    Science.gov (United States)

    Koshkin, N.; Burlak, N.; Petrov, M.; Strakhova, S.

    The indicatrices of light scattering by radiation balance coatings used on space objects (SO) were determined in the laboratory experiment in a controlled condition. The laboratory device for the physical simulation of photometric observations of space objects in orbit, which was used in this case to study optical properties of coating samples, is described. The features of light reflection off plane coating samples, including multi-layer insulation (MLI) blankets, metal surfaces coated with several layers of enamel EP-140, special polyacrylate enamel AK-512 and matte finish Tp-CO-2, were determined. The indicated coatings are compound reflectors which exhibit both diffuse and specular reflections. The data obtained are to be used in the development of computer optical-geometric models of space objects or their fragments (space debris) to interpret the photometry results for real space objects.

  19. Inside Solomon's house: an archaeological study of the Old Ashmolean chymical laboratory in Oxford.

    Science.gov (United States)

    Martinón-Torres, Marcos

    2012-03-01

    This paper is based on the archaeological and analytical study of the laboratory remains from the Officina Chimica of the Old Ashmolean Museum in Oxford. Following a contextualisation of this laboratory, founded in the wake of Bacon's utopian idea of Solomon's Temple, it is argued that the assemblage is likely to date from the late seventeenth century and thus be connected to the work of Robert Plot, Christopher White, and, indirectly, Robert Boyle. The analytical study of the equipment reveals that the chymists at the Old Ashmolean obtained crucibles from the best manufacturers in Europe, and that they used these and other utensils for experiments involving mercury, sulphur, zinc, lead glass, manganese, and antimony. The importance of these elements for early modern chymistry is discussed in the light of relevant historical sources, including some of Boyle's chymical texts. Altogether, these finds illustrate some of the rich diversity of experiments that took place in one of the most prominent laboratories of the period, showing strong connections with longstanding alchemical concerns as well as with cutting-edge research and development ventures.

  20. Biofilm resilience to desiccation in groundwater aquifers: a laboratory and field study.

    Science.gov (United States)

    Weaver, L; Webber, J B; Hickson, A C; Abraham, P M; Close, M E

    2015-05-01

    Groundwater is used as a precious resource for drinking water worldwide. Increasing anthropogenic activity is putting increasing pressure on groundwater resources. One impact of increased groundwater abstraction coupled with increasing dry weather events is the lowering of groundwater levels within aquifers. Biofilms within groundwater aquifers offer protection to the groundwater by removing contaminants entering the aquifer systems from land use activities. The study presented investigated the impact of desiccation events on the biofilms present in groundwater aquifers using field and laboratory experiments. In both field and laboratory experiments a reduction in enzyme activity (glucosidase, esterase and phosphatase) was seen during desiccation compared to wet controls. However, comparing all the data together no significant differences were seen between either wet or desiccated samples or between the start and end of the experiments. In both field and laboratory experiments enzyme activity recovered to start levels after return to wet conditions. The study shows that biofilms within groundwater systems are resilient and can withstand periods of desiccation (4 months).

  1. Emotions beyond the laboratory: theoretical fundaments, study design, and analytic strategies for advanced ambulatory assessment.

    Science.gov (United States)

    Wilhelm, Frank H; Grossman, Paul

    2010-07-01

    Questionnaire and interview assessment can provide reliable data on attitudes and self-perceptions on emotion, and experimental laboratory assessment can examine functional relations between stimuli and reactions under controlled conditions. On the other hand, ambulatory assessment is less constrained and provides naturalistic data on emotion in daily life, with the potential to (1) assure external validity of laboratory findings, (2) provide normative data on prevalence, quality and intensity of real-life emotion and associated processes, (3) characterize previously unidentified emotional phenomena, and (4) model real-life stimuli for representative laboratory research design. Technological innovations now allow for detailed ambulatory study of emotion across domains of subjective experience, overt behavior and physiology. However, methodological challenges abound that may compromise attempts to characterize biobehavioral aspects of emotion in the real world. For example, emotional effects can be masked by social engagement, mental and physical workloads, as well as by food intake and circadian and quasi-random variation in metabolic activity. The complexity of data streams and multitude of factors that influence them require a high degree of context specification for meaningful data interpretation. We consider possible solutions to typical and often overlooked issues related to ambulatory emotion research, including aspects of study design decisions, recording devices and channels, electronic diary implementation, and data analysis.

  2. A melanoma case-control study at the Los Alamos National Laboratory.

    Science.gov (United States)

    Acquavella, J F; Wilkinson, G S; Tietjen, G L; Key, C R; Stebbings, J H; Voelz, G L

    1983-09-01

    We conducted a melanoma case-control study at the Los Alamos National Laboratory to investigate whether related occupational exposures or personal characteristics of employees could be identified. This study was prompted by a recent report from the Lawrence Livermore National Laboratory that melanoma was much more frequent than expected among employees and that persons suffering from melanoma more often worked as chemists. Our investigation did not uncover an association with plutonium body burden, cumulative external radiation exposure, or employment as a chemist or a physicist. The major finding was that cases were more educated than controls. Melanoma risk was 2.11 among college-educated employees and increased to 3.17 among those with graduate degrees (Mantel-extension linear trend probability = 0.038). This finding is consistent with the often reported increased melanoma incidence among persons of higher social class. It points to personal characteristics, particular to persons of higher educational attainment, as risk factors for melanoma at the Los Alamos National Laboratory.

  3. Obesity rates in two generations of Swedish women entering pregnancy, and associated obesity risk among adult daughters.

    Science.gov (United States)

    Derraik, José G B; Ahlsson, Fredrik; Diderholm, Barbro; Lundgren, Maria

    2015-11-13

    We examined changes in obesity rates in two generations of Swedish women entering pregnancy, and assessed the effects of maternal body mass index (BMI) on the risk of overweight or obesity among adult daughters. This study covered an intergenerational retrospective cohort of 26,561 Swedish mothers and their 26,561 first-born daughters. There was a 4-fold increase in obesity rates, which rose from 3.1% among women entering pregnancy in 1982-1988 to 12.3% among their daughters in 2000-2008 (p pregnancy. The greater the maternal BMI, the greater the odds of overweight and/or obesity among daughters. Underweight mothers had half the odds of having an overweight or obese daughter in comparison to mothers of normal BMI (p obese mothers having obese daughters was 3.94 (p obesity and the risk of obesity among their first-born daughters. In addition, we observed a considerable increase in obesity rates across generations in mother-daughter pairs of Swedish women entering pregnancy. Thus, it is important to have preventative strategies in place to halt the worsening intergenerational cycle of obesity.

  4. Stability in chromosome number and DNA content in synthetic tetraploids of Lolium multiflorum after two generations of selection

    Directory of Open Access Journals (Sweden)

    Roselaine Cristina Pereira

    Full Text Available ABSTRACT: Chromosome doubling of Italian ryegrass genotypes ( Lolium multiflorum Lam. adapted to the brazilian edaphoclimatic conditions is an important strategy used by breeders and aims to obtain more vigorous genotypes with better forage quality and disease resistance. The effectiveness of chromosome doubling can be measured by genetic stability and fertility rates of plants over generations. However, a common problem in the polyploidization process is the regeneration of mixoploid plants that have impaired fertility and genetic stability. The objective of this study was to verify if progenies of recently tetraploidized plants remain stable regarding DNA content and chromosome number, over two generations. Progenies of L. multiflorum plants artificially tetraploidized with colchicine treatment were evaluated. Chromosome counting and estimates of the DNA content were used to evaluate the genetic stability. The percentage of tetraploid plants (4X increased over generations (18%, 34% and 91% in cycle 0, 1 and 2, respectively. All progenies identified as tetraploid by flow citometry showed variation in chromosome number (mixoploidy, but produced viable seeds. Results showed that stabilization in chromosome number and DNA content in tetraploidized plant progenies requires time and that the success of this procedure depends on a continuous and accurate screening and selection.

  5. Effects of low doses of short-term gamma irradiation on growth and development through two generations of Pisum sativum

    Energy Technology Data Exchange (ETDEWEB)

    Zaka, R.; Misset, M.T. [UMR-CNRS 6553 Ecobio, Equipe Evolution des Populations et des Especes, Universite de Rennes 1, Campus de Beaulieu Bat. 14, Rennes Cedex F 35042 (France); Chenal, C. [Laboratoire de Radiobiologie, Universite de Rennes 1, Centre Regional de Lutte contre le Cancer, Rennes Cedex F 35062 (France)

    2004-03-29

    The effects of short-term gamma radiation on pea plants were investigated by exposing 5-day-old seedlings with doses ranging from 0 to 60 Gy, and studying plant growth and development over two generations after irradiation. Doses higher than 6 Gy significantly inhibited the G1 plant growth and productivity, and no seedling survived irradiation with 40 Gy and above. These effects were transmitted and were even more severe in the next generation, G2. Irradiated G1 ({>=}10 Gy) and G2 ({>=}0.4 Gy) plants were significantly smaller than controls. The mean number of pods produced per plant was reduced by at least 20% at all doses in both G1 and G2. In parallel, the mean numbers of ovules and normally developed seeds per pod were significantly reduced after 10 Gy in G1 and after 0.4 Gy in G2, leading to a significant drop in seed production. This effect was correlated with a linear decrease in male fertility linked to abnormal meiosis (tetrads with micronuclei) as a function of doses from 0 to 10 Gy, in G1 and G2 plants. These long-term changes in plant development demonstrate a genomic instability induced by irradiation. However, there were neither quantitative nor qualitative changes in storage proteins in G1 seeds at any of the irradiation doses tested from 0 to 10 Gy.

  6. Possible effect of landscape design on IgE recognition profiles of two generations revealed with micro-arrayed allergens.

    Science.gov (United States)

    Garib, V; Wollmann, E; Djambekova, G; Lemell, P; Kmenta, M; Berger, U; Zieglmayer, P; Valenta, R

    2017-10-01

    The aim of this study was to investigate possible effects of landscape design on the IgE sensitization profile toward inhalant allergens in patients with respiratory allergy from Uzbekistan where green areas have been changed during the last two decades by a State program. Sera from two different generations of Uzbek (n=58) and, for control purposes, from two generations of Austrian (n=58) patients were analyzed for IgE reactivity to 112 different micro-arrayed allergen molecules by ImmunoCAP ISAC technology. Changes in molecular IgE sensitization profiles to pollen allergens in the young vs the middle-aged Uzbek population were associated with replanting, whereas those in the Vienna populations reflected natural changes in plant growth. Our data indicate that anthropologic as well as natural changes in the biome may have effects on IgE sensitization profiles already from one to another generation. © 2017 The Authors Allergy Published by John Wiley and Sons Ltd.

  7. Labtracker+, a medical smartphone app for the interpretation of consecutive laboratory results: an external validation study.

    Science.gov (United States)

    Hilderink, Judith M; Rennenberg, Roger J M W; Vanmolkot, Floris H M; Bekers, Otto; Koopmans, Richard P; Meex, Steven J R

    2017-09-01

    When monitoring patients over time, clinicians may struggle to distinguish 'real changes' in consecutive blood parameters from so-called natural fluctuations. In practice, they have to do so by relying on their clinical experience and intuition. We developed Labtracker+, a medical app that calculates the probability that an increase or decrease over time in a specific blood parameter is real, given the time between measurements. We presented patient cases to 135 participants to examine whether there is a difference between medical students, residents and experienced clinicians when it comes to interpreting changes between consecutive laboratory results. Participants were asked to interpret if changes in consecutive laboratory values were likely to be 'real' or rather due to natural fluctuations. The answers of the study participants were compared with the calculated probabilities by the app Labtracker+ and the concordance rates were assessed. Medical students (n=92), medical residents from the department of internal medicine (n=19) and internists (n=24) at a Dutch University Medical Centre. Concordance rates between the study participants and the calculated probabilities by the app Labtracker+ were compared. Besides, we tested whether physicians with clinical experience scored better concordance rates with the app Labtracker+ than inexperienced clinicians. Medical residents and internists showed significantly better concordance rates with the calculated probabilities by the app Labtracker+ than medical students, regarding their interpretation of differences between consecutive laboratory results (p=0.009 and p<0.001, respectively). The app Labtracker+ could serve as a clinical decision tool in the interpretation of consecutive laboratory test results and could contribute to rapid recognition of parameter changes by physicians. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial

  8. A review of published quantitative experimental studies on factors affecting laboratory fume hood performance.

    Science.gov (United States)

    Ahn, Kwangseog; Woskie, Susan; DiBerardinis, Louis; Ellenbecker, Michael

    2008-11-01

    This study attempted to identify the important factors that affect the performance of a laboratory fume hood and the relationship between the factors and hood performance under various conditions by analyzing and generalizing the results from other studies that quantitatively investigated fume hood performance. A literature search identified 43 studies that were published from 1966 to 2006. For each of those studies, information on the type of test methods used, the factors investigated, and the findings were recorded and summarized. Among the 43 quantitative experimental studies, 21 comparable studies were selected, and then a meta-analysis of the comparable studies was conducted. The exposure concentration variable from the resulting 617 independent test conditions was dichotomized into acceptable or unacceptable using the control level of 0.1 ppm tracer gas. Regression analysis using Cox proportional hazards models provided hood failure ratios for potential exposure determinants. The variables that were found to be statistically significant were the presence of a mannequin/human subject, the distance between a source and breathing zone, and the height of sash opening. In summary, performance of laboratory fume hoods was affected mainly by the presence of a mannequin/human subject, distance between a source and breathing zone, and height of sash opening. Presence of a mannequin/human subject in front of the hood adversely affects hood performance. Worker exposures to air contaminants can be greatly reduced by increasing the distance between the contaminant source and breathing zone and by reducing the height of sash opening. Many other factors can also affect hood performance. Checking face velocity by itself is unlikely to be sufficient in evaluating hood performance properly. An evaluation of the performance of a laboratory fume hood should be performed with a human subject or a mannequin in front of the hood and should address the effects of the activities

  9. Laboratory assessment of sudden sensorineural hearing loss: A case-control study.

    Science.gov (United States)

    Fasano, Tommaso; Pertinhez, Thelma A; Tribi, Lorenzo; Lasagni, Daniela; Pilia, Annalisa; Vecchia, Luigi; Baricchi, Roberto; Bianchin, Giovanni

    2017-10-01

    Sudden sensorineural hearing loss (SSHL) is an otologic emergency that affects five to 30 subjects per 100,000/year. The cause of SSHL remains unknown or uncertain in 70% to 90% of cases, and treatment decisions are usually made without knowing the etiology. Prospective case-control study. One hundred thirty-one idiopathic SSHL patients were recruited from January 2014 to June 2015 in concordance with the Statements of Clinical Practice Guideline and divided into groups according to the disease severity. A clinical laboratory assessment was completed on blood samples collected from SSHL patients and control subjects. Multivariable regression analysis was performed to investigate the association between laboratory data and SSHL basis. Only a few SSHL patients were positive for autoimmunity or viral infection. Statistically significant (P < .05) higher levels of blood glucose, glycated hemoglobin (HbA1C), lipoprotein (a), and factor VIII were found in SSHL patients compared to controls. Furthermore, blood glucose, HbA1C, uric acid, factor VIII, and homocysteine were significantly associated to disease severity. Gluco-metabolic, lipidic, and coagulative laboratory data support the vascular hypothesis for SSHL and its severity. 3b Laryngoscope, 127:2375-2381, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  10. Analysis of degradation in UHMWPE a comparative study among the various commercial and laboratory grades UHMWPE

    Science.gov (United States)

    Azam, A. M.; Ali, A.; Khan, H.; Yasin, T.; Mehmood, M. S.

    2016-08-01

    Oxidative degradation of the ultra-high molecular weight polyethylene (UHMWPE) limits the life of implants. This degradation can be monitored to estimate the service life of UHMWPE following the standard protocols as defined by American Standards for Testing Materials (ASTM). In this work, a comparative study has been carried on two commercially available UHMWPE grades i.e. GUR 1020 and GUR 1050 and one laboratory grade UHMWPE which was purchased from Sigma Aldrich. These powder samples were pressed while using hot press with controlled heating and cooling setup in open air under 200 bar of external pressure. These sheets were then subjected to accelerated aging in an oven at 80 °C for three weeks. The degradation of the UHMWPE was monitored by ATR-FTIR techniquefor three weeks. The oxidation index (OI) measurement showed that the commercial grade UHMWPE i.e. GUR-1020 and GUR-1050 degrade more as compared to laboratory grade UHMWPE. The values of OI after three weeks of accelerating aging were found 0.18, 0.14, and 0.09 for GUR-1020, GUR-1050, and Sigma Aldrich, respectively. In addition to this, it was found that commercial grades of UHMWPE suffer more structural alterations as compared to laboratory grade one. We hope that these results will be of particular and fundamental importance for the researchers and orthopaedic industry.

  11. Linking accelerated laboratory and outdoor exposure results for PV polymeric materials: a mechanistic study of EVA

    Science.gov (United States)

    Gu, Xiaohong; Pang, Yongyan; Lin, Chiao-Chi; Liu, Kaipeng; Nguyen, Tinh; Chin, Jaonnie W.

    2013-09-01

    Linking accelerated laboratory test to field performance for predicting the service life of polymeric materials are being investigated at NIST using the reliability-based methodology. Based on this methodology, a successful linkage between the laboratory and field exposure data for a model polymeric material has been made. Recently, this methodology, for the first time, was introduced to the lifetime assessment of PV polymeric materials. In this paper, a mechanistic study of the degradation of three unstabilized model ethylene vinyl acetate (EVA) systems---uncured EVA, cured EVA and laminated EVA---was carried out under accelerated laboratory exposure and outdoor exposure. The NIST SPHERE (Simulated Photodegradation via High Energy Radiant Exposure) was used for the accelerated laboratory tests, and the outdoor exposure was conducted in Gaithersburg, Maryland. Simultaneous multiple stresses, including temperature, relative humidity and UV radiation, were applied individually or in combination during SPHERE exposure. The effects of the environmental factors on the main degradation mechanisms of different EVA systems were investigated. The results showed that the UV radiation was the most important factor for the degradation of EVA and a synergistic effect occurred between UV radiation and relative humidity. A slower degradation rate was observed for the laminated system as a result of limited diffusion of O2 and H2O into EVA. It was also found that the substantial chemical changes of the uncured EVA system did not yield yellowing, which was dramatically different from the peroxide cured EVA system. Additionally, the chemical degradation modes of the three EVA systems exposed outdoors appeared to be similar to those exposed to the SPHERE. The implication of this work to the current test standards was discussed.

  12. Thermogravimetric Analysis Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — At NETL’s Thermogravimetric Analysis Laboratory in Morgantown, WV, researchers study how chemical looping combustion (CLC) can be applied to fossil energy systems....

  13. ANALYTICAL MICROBIOLOGY LABORATORY

    Data.gov (United States)

    Federal Laboratory Consortium — This laboratory contains equipment that performs a broad array of microbiological analyses for pathogenic and spoilage microorganisms. It performs challenge studies...

  14. Neural Systems Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — As part of the Electrical and Computer Engineering Department and The Institute for System Research, the Neural Systems Laboratory studies the functionality of the...

  15. COGNITIVE PERFORMANCE LABORATORY

    Data.gov (United States)

    Federal Laboratory Consortium — This laboratory conducts basic and applied human research studies to characterize cognitive performance as influenced by militarily-relevant contextual and physical...

  16. GeoBrain Computational Cyber-laboratory for Earth Science Studies

    Science.gov (United States)

    Deng, M.; di, L.

    2009-12-01

    Computational approaches (e.g., computer-based data visualization, analysis and modeling) are critical for conducting increasingly data-intensive Earth science (ES) studies to understand functions and changes of the Earth system. However, currently Earth scientists, educators, and students have met two major barriers that prevent them from being effectively using computational approaches in their learning, research and application activities. The two barriers are: 1) difficulties in finding, obtaining, and using multi-source ES data; and 2) lack of analytic functions and computing resources (e.g., analysis software, computing models, and high performance computing systems) to analyze the data. Taking advantages of recent advances in cyberinfrastructure, Web service, and geospatial interoperability technologies, GeoBrain, a project funded by NASA, has developed a prototype computational cyber-laboratory to effectively remove the two barriers. The cyber-laboratory makes ES data and computational resources at large organizations in distributed locations available to and easily usable by the Earth science community through 1) enabling seamless discovery, access and retrieval of distributed data, 2) federating and enhancing data discovery with a catalogue federation service and a semantically-augmented catalogue service, 3) customizing data access and retrieval at user request with interoperable, personalized, and on-demand data access and services, 4) automating or semi-automating multi-source geospatial data integration, 5) developing a large number of analytic functions as value-added, interoperable, and dynamically chainable geospatial Web services and deploying them in high-performance computing facilities, 6) enabling the online geospatial process modeling and execution, and 7) building a user-friendly extensible web portal for users to access the cyber-laboratory resources. Users can interactively discover the needed data and perform on-demand data analysis and

  17. Field, laboratory, and X-ray absorption spectroscopic studies of mercury accumulation by water hyacinths.

    Science.gov (United States)

    Riddle, Sarah G; Tran, Huy H; Dewitt, Jane G; Andrews, Joy C

    2002-05-01

    We have studied water hyacinth (Eichhornia crassipes), a non-native nuisance plant found in the in San Francisco Bay Delta region, for its potential to phytoremediate mercury. Mercury is a common contaminant in San Francisco Bay Area waters because of gold mining activities. In this study, speciation of mercury in hyacinth roots and shoots, rates of mercury uptake by hyacinths in the laboratory, and mercury levels near the Big Break Region in the Delta were studied. In the speciation studies, Hg L3 edge X-ray absorption spectroscopic analysis of Hg model compounds and water hyacinth roots and shoots revealed that Hg was initially bound ionically to oxygen ligands in roots, most likely to carboxylate groups, and was bound covalently to sulfur groups in shoots. In laboratory uptake studies, we found that water hyacinths grown in 1 ppm Hg and one-quarter strength Hoagland's solution accumulated a maximum of 0.20 ppm in shoots and 16.0 ppm in roots, both reaching maximum concentrations after approximately 16 days. Mercury concentrations were found to be 0.26 +/- 0.20 ppm in the water and 0.86 +/- 1.70 ppm in sediment at Big Break. It was proposed that water hyacinths have the potential to phytoremediate mercury in the water at Big Break if the current herbicide treatments are replaced by physical removal.

  18. Lawrence Livermore National Laboratory East Avenue/Emergency Response Planning Traffic Study

    Energy Technology Data Exchange (ETDEWEB)

    Schmiegel, T

    2002-02-15

    The Lawrence Livermore National Laboratory (LLNL) and the Sandia National Laboratory (SNL) are located at the eastern end of the City of Livermore. Recently the research facilities have been placed on heightened security alerts due to the events of September 11. To respond to the security concerns, LLNL and SNL have proposed to place East Avenue between South Vasco Road and Greenville Road under administrative control. This type of control would require security check points at both ends of this segment of East Avenue, including a truck inspection facility west of the Greenville Road intersection. In this configuration, East Avenue would be closed to general public traffic. The purpose of this traffic study is to determine the potential traffic impact of placing East Avenue under administrative control. The primary focus of the traffic study is to evaluate the proposed modifications to the geometry and operation of East Avenue between South Vasco Road and Greenville Road. The study also includes a review of a traffic study prepared for the closure of East Avenue in 1989 to determine if the assumptions and conclusions of that study remain valid.

  19. Laboratory studies on surface sampling of Bacillus anthracis contamination: summary, gaps and recommendations.

    Science.gov (United States)

    Piepel, G F; Amidan, B G; Hu, R

    2012-12-01

    This article summarizes previous laboratory studies to characterize the performance of methods for collecting, storing/transporting, processing and analysing samples from surfaces contaminated by Bacillus anthracis or related surrogates. The focus is on plate culture and count estimates of surface contamination for swab, wipe and vacuum samples of porous and nonporous surfaces. Summaries of the previous studies and their results were assessed to identify gaps in information needed as inputs to calculate key parameters critical to risk management in biothreat incidents. One key parameter is the number of samples needed to make characterization or clearance decisions with specified statistical confidence. Other key parameters include the ability to calculate, following contamination incidents, the (i) estimates of B. anthracis contamination, as well as the bias and uncertainties in the estimates and (ii) confidence in characterization and clearance decisions for contaminated or decontaminated buildings. Gaps in knowledge and understanding identified during the summary of the studies are discussed. Additional work is needed to quantify (i) the false-negative rates of surface-sampling methods with lower concentrations on various surfaces and (ii) the effects on performance characteristics of: aerosol vs liquid deposition of spores, using surrogates instead of B. anthracis, real-world vs laboratory conditions and storage and transportation conditions. Recommendations are given for future evaluations of data from existing studies and possible new studies.

  20. Study of variables affecting critical value notification in a laboratory catering to tertiary care hospital.

    Science.gov (United States)

    Agarwal, Rachna; Chhillar, Neelam; Tripathi, Chandra B

    2015-01-01

    During post-analytical phase, critical value notification to responsible caregiver in a timely manner has potential to improve patient safety which requires cooperative efforts between laboratory personnel and caregivers. It is widely accepted by hospital accreditors that ineffective notification can lead to diagnostic errors that potentially harm patients and are preventable. The objective of the study was to assess the variables affecting critical value notification, their role in affecting it's quality and approaches to improve it. In the present study 1,187 critical values were analysed in the Clinical Chemistry Laboratory catering to tertiary care hospital for neuropsychiatric diseases. During 25 months of study period, we evaluated critical value notification with respect to clinical care area, caregiver to whom it was notified and timeliness of notification. During the study period (25 months), the laboratory obtained 1,279 critical values in clinical chemistry. The analytes most commonly notified were sodium and potassium (20.97 & 20.8 % of total critical results). Analysis of critical value notification versus area of care showed that critical value notification was high in ICU and emergency area followed by inpatients and 64.61 % critical values were notified between 30 and 120 min after receiving the samples. It was found that failure to notify the responsible caregiver in timely manner represent an important patient safety issue and may lead to diagnostic errors. The major area of concern are notification of critical value for outpatient samples, incompleteness of test requisition forms regarding illegible writing, lack of information of treating physician and location of test ordering and difficulty in contacting the responsible caregiver.

  1. Studying human disease genes in Caenorhabditis elegans: a molecular genetics laboratory project.

    Science.gov (United States)

    Cox-Paulson, Elisabeth A; Grana, Theresa M; Harris, Michelle A; Batzli, Janet M

    2012-01-01

    Scientists routinely integrate information from various channels to explore topics under study. We designed a 4-wk undergraduate laboratory module that used a multifaceted approach to study a question in molecular genetics. Specifically, students investigated whether Caenorhabditis elegans can be a useful model system for studying genes associated with human disease. In a large-enrollment, sophomore-level laboratory course, groups of three to four students were assigned a gene associated with either breast cancer (brc-1), Wilson disease (cua-1), ovarian dysgenesis (fshr-1), or colon cancer (mlh-1). Students compared observable phenotypes of wild-type C. elegans and C. elegans with a homozygous deletion in the assigned gene. They confirmed the genetic deletion with nested polymerase chain reaction and performed a bioinformatics analysis to predict how the deletion would affect the encoded mRNA and protein. Students also performed RNA interference (RNAi) against their assigned gene and evaluated whether RNAi caused a phenotype similar to that of the genetic deletion. As a capstone activity, students prepared scientific posters in which they presented their data, evaluated whether C. elegans was a useful model system for studying their assigned genes, and proposed future directions. Assessment showed gains in understanding genotype versus phenotype, RNAi, common bioinformatics tools, and the utility of model organisms.

  2. 'Population laboratories' or 'laboratory populations'? Making sense of the Baltimore Longitudinal Study of Aging, 1965-1987

    NARCIS (Netherlands)

    Moreira, Tiago; Palladino, Paolo

    2011-01-01

    Interest among historians, philosophers and sociologists of science in population-based biomedical research has focused on the randomised controlled trial to the detriment of the longitudinal study, the temporally extended, serial observation of individuals residing in the same community. This is pe

  3. Pre-Service Chemistry Teachers' Competencies in the Laboratory: A Cross-Grade Study in Solution Preparation

    Science.gov (United States)

    Karatas, F. O.

    2016-01-01

    One of the prerequisites for chemistry teacher candidates is to demonstrate certain laboratory skills. This article aims to determine and discuss the competencies of pre-service chemistry teachers in a chemistry laboratory context working with solution chemistry content. The participants in this study consisted of a group of pre-service chemistry…

  4. [Experience of the development special medical technical laboratory for studies of effects caused by potent electromagnetic radiation in biologic objects].

    Science.gov (United States)

    Gorodetsky, B N; Kalyada, T V; Petrov, S V

    2015-01-01

    This article covers topics of creating special medical technical laboratory for medial and biologic studies concerning influence of potent high-frequency elecromagnetic radiation on various biologic objects. The authors gave example of such laboratory, described its construction features, purpose and main characteristics of the included devices.

  5. Anisotropic Rotational Diffusion Studied by Nuclear Spin Relaxation and Molecular Dynamics Simulation: An Undergraduate Physical Chemistry Laboratory

    Science.gov (United States)

    Fuson, Michael M.

    2017-01-01

    Laboratories studying the anisotropic rotational diffusion of bromobenzene using nuclear spin relaxation and molecular dynamics simulations are described. For many undergraduates, visualizing molecular motion is challenging. Undergraduates rarely encounter laboratories that directly assess molecular motion, and so the concept remains an…

  6. The nucleation of aerosols in flue gases with a high content of alkali - a laboratory study

    DEFF Research Database (Denmark)

    Jensen, Joakim Reimer; Schultz-Møller, Christina; Wedel, Stig;

    2000-01-01

    The formation of particles during cooling of a synthetic flue gas with vapors of sodium and potassium species is studied in a laboratory tubular reactor with laminar flow. It is shown to agree well with a theoretical model for the process. The kinetics of homogeneous nucleation of the pure chloride...... are determined from the measurements. The homogeneous nucleation of the pure chlorides is suppressed by even relatively small concentrations of foreign seed particles and is therefore unlikely to contribute to the creation of new particles in real flue gases. The addition of SO2 to the chloride vapor feed...

  7. Control of the northern fowl mite on inanimate objects by fumigation: laboratory studies.

    Science.gov (United States)

    Beerwinkle, K R; Devaney, J A

    1983-01-01

    Laboratory studies were conducted to determine the efficacies of phosphine, methyl bromide, and sulfur dioxide as fumigants for the northern fowl mite, Ornithonyssus sylviarum (Canestrini and Fanzago), on inanimate objects. We were able to demonstrate that either methyl bromide or sulfur dioxide could kill all physiological forms of mites within 24 hr, which would be desirable for field use. Prosphine gas, released from Phostoxin pellets, had an LD95 of 18 hr for motile forms of the mites; however, it took 30 hr to kill the mite eggs. Therefore, it would be an unsuitable fumigant for practical field usage.

  8. A laboratory study of low-mode internal tide scattering by finite-amplitude topography

    CERN Document Server

    Peacock, Thomas; Didelle, Henri; Viboud, Samuel; Dauxois, Thierry

    2015-01-01

    We present the first laboratory experimental results concerning the scattering of a low-mode internal tide by a gaussian topography. Experiments performed at the Coriolis Platform in Grenoble used a recently-conceived internal wave generator as a means of producing a high-quality mode-1 wave field. The evolution of the wave field in the absence and presence of a supercritical Gaussian was studied by performing spatiotemporal modal decompositions of velocity field data obtained using Particle Image Velocimetry (PIV). The results support predictions that large-amplitude supercritical topography produces significant reflection of the internal tide and transfer of energy from low to high modes.

  9. Effects of implant angulation, material selection, and impression technique on impression accuracy: a preliminary laboratory study.

    Science.gov (United States)

    Rutkunas, Vygandas; Sveikata, Kestutis; Savickas, Raimondas

    2012-01-01

    The aim of this preliminary laboratory study was to evaluate the effects of 5- and 25-degree implant angulations in simulated clinical casts on an impression's accuracy when using different impression materials and tray selections. A convenience sample of each implant angulation group was selected for both open and closed trays in combination with one polyether and two polyvinyl siloxane impression materials. The influence of material and technique appeared to be significant for both 5- and 25-degree angulations (P impression accuracy. The open-tray technique was more accurate with highly nonaxially oriented implants for the small sample size investigated.

  10. An inter-laboratory stability study of roll-to-roll coated flexible polymer solar modules

    DEFF Research Database (Denmark)

    Gevorgyan, Suren; Medford, Andrew James; Bundgaard, Eva

    2011-01-01

    O (nanoparticulate, thin film) were employed as electron transport layers. The devices were all tested at Risø DTU and the functional devices were subjected to an inter-laboratory study involving the performance and the stability of modules over time in the dark, under light soaking and outdoor conditions. 24......A large number of flexible polymer solar modules comprising 16 serially connected individual cells was prepared at the experimental workshop at Risø DTU. The photoactive layer was prepared from several varieties of P3HT (Merck, Plextronics, BASF and Risø DTU) and two varieties of Zn...

  11. Beta decay studies of r-process nuclei at the National Superconducting Cyclotron Laboratory

    CERN Document Server

    Pereira, J; Arndt, O; Becerril, A; Elliot, T; Estrade, A; Galaviz, D; Hennrich, S; Hosmer, P; Kessler, R; Kratz, K L; Lorusso, G; Mantica, P F; Matos, M; Montes, F; Santi, P; Pfeiffer, B; Quinn, M; Schatz, H; Schertz, F; Schnorrenberger, L; Smith, E; Tomlin, B E; Walters, W; Wöhr, A

    2009-01-01

    The impact of nuclear physics on astrophysical r-process models is discussed, emphasizing the importance of beta-decay properties of neutron-rich nuclei. Several r-process motivated beta-decay experiments performed at the National Superconducting Cyclotron Laboratory are presented. The experiments include the measurement of beta-decay half-lives and neutron emission probabilities of nuclei in regions around Ni-78; Se-90; Zr-106 and Rh-120, as well as spectroscopic studies of Pd-120. A summary on the different experimental techniques employed, data analysis, results and impact on model calculations is presented.

  12. The LUNA experiment at Gran Sasso Laboratory: Studying stars by going underground

    Energy Technology Data Exchange (ETDEWEB)

    Guglielmetti, Alessandra [Università degli Studi di Milano and INFN Milano Via Celoria 16, I-20133 Milano,ITALY (Italy)

    2015-10-15

    Accurate knowledge of thermonuclear reaction rates is a key issue in nuclear astrophysics: it is important for understanding the energy generation, neutrino production and the synthesis of the elements in stars and during primordial nucleosynthesis. Cross-section measurements are mainly hampered by the very low counting rate and cosmic background. An underground location is extremely advantageous for such studies, as demonstrated by the LUNA experiment in the Gran Sasso Laboratory (Italy). This paper reports on the results recently obtained by this experiment and on the future perspectives in the field.

  13. Studying the Earth's Environment from Space: Computer Laboratory Exercised and Instructor Resources

    Science.gov (United States)

    Smith, Elizabeth A.; Alfultis, Michael

    1998-01-01

    Studying the Earth's Environment From Space is a two-year project to develop a suite of CD-ROMs containing Earth System Science curriculum modules for introductory undergraduate science classes. Lecture notes, slides, and computer laboratory exercises, including actual satellite data and software, are being developed in close collaboration with Carla Evans of NASA GSFC Earth Sciences Directorate Scientific and Educational Endeavors (SEE) project. Smith and Alfultis are responsible for the Oceanography and Sea Ice Processes Modules. The GSFC SEE project is responsible for Ozone and Land Vegetation Modules. This document constitutes a report on the first year of activities of Smith and Alfultis' project.

  14. QUASIMEME laboratory performance study of the biological effects of tributyltin (imposex and intersex) on two marine gastropod molluscs.

    Science.gov (United States)

    Davies, I M; Minchin, A; Bauer, B; Harding, M J; Wells, D E

    1999-06-01

    The disruption of the endocrine systems of gastropod molluscs and consequential physiological changes (imposex and intersex) are used as biomarkers for environmental contamination by tributyltin compounds. The first international laboratory performance study on the determination of imposex and intersex in neogastropod molluscs, Nucella lapillus and Littorina littorea has been undertaken by the QUASIMEME (Quality Assurance of Information for Marine Environmental Monitoring in Europe) project. Samples of live gastropods were distributed and participants were asked to record shell height and sex, together with penis length and vas deferens sequence stage (VDS) in Nucella or the intersex stage (IS) and prostate length in Littorina. Calculations were made of vas deferens sequence index (VDSI) and the relative penis size index (RPSI) in Nucella and of intersex stage index (ISI) and the average female prostate length (FPrL) in Littorina. Thirteen (87%) of the 15 participating laboratories returned data. The remaining two laboratories asked to participate in later exercises. For Nucella, seven laboratories reported sex ratios significantly different from the reference laboratory data. Differences in penis length measurements between laboratories were largely random, although there were indications of systematic errors affecting the data from three laboratories. Seven laboratories reported satisfactory data (Z-score magnitude of Z penis length or observation of reproductive organs would have a potentially greater impact on the final reported values of the summary imposex indices. The Littorina sample did not show a high degree of intersex (ISI = 0.41). The laboratories could determine the sex of Littorina reliably and only one laboratory reported data significantly different from the reference laboratory. All except two laboratories reported satisfactory data for ISI.

  15. Performance of the Aachen Acoustic Laboratory and results from comparative studies in water and ice

    Science.gov (United States)

    Heinen, Dirk; Paul, Larissa; Wiebusch, Christopher

    2013-05-01

    To investigate acoustic ice properties under laboratory conditions and to test the thermoacoustic model, the Aachen Acoustic Laboratory (AAL) was founded as a part of the activities of the acoustic working group (SPATS) within the IceCube collaboration. The goal of SPATS is to evaluate the possibility of acoustic detection of ultra high-energy neutrinos in the Antarctic ice. The AAL provides a test facility setup with a proper infrastructure to study acoustics and thermoacoustics in a large volume of water and ice. The control of the freezing process, the ice quality, the temperature monitoring at different phases of the medium and the laser-based thermoacoustic sound generation are the key features of the setup. The AAL setup provides the possibility for the characterization of a wide range of acoustic transducers, sensor/transmitter calibration, study of the thermoacoustic sound generation, study of the acoustic properties of the ice, water as well as the water/ice interfaces, and research and development of new types of acoustic transducers (PVDF-based) as an alternative to standard PZTs. In this document, the different parts of the AAL setup are described, results on the commissioning from the laser based thermoacoustic sound generation are presented and the performance of an absolute sensor calibration method in water and ice are discussed.

  16. Understanding Authentic Assessment in a Secondary Agricultural Mechanics Laboratory: An Instrumental Case Study

    Directory of Open Access Journals (Sweden)

    J. Joey Blackburn

    2013-06-01

    Full Text Available The instrumental case study reported here adds to the literature on authentic assessment by illuminating how one secondary agricultural education instructor employed authentic assessment in the agricultural mechanics laboratory. The study was underpinned by the constructivist notion of authentic learning and assessment, or allowing students to perform what they can do. Multiple sources of data regarding assessment practices were collected from an exemplary secondary agricultural mechanics instructor who demonstrated model authentic assessment behavior by (1 setting high and fair expectations for students, (2 establishing a progressive hierarchy of skills for students to master, (3 providing continuous feedback so that students had knowledge of their progress, and (4 being committed deeply to students’ success. The four themes resonated with previous literature and provided the foundation for a pragmatic model of authentic assessment in the secondary agricultural mechanics laboratory. Future research should focus on refining the model of authentic assessment in agricultural mechanics for a larger audience, as case studies are limited in their ability to generalize. Additionally, research should be conducted to determine how authentic assessment impacts student performance on Oklahoma Agricultural Power and Technology competency examinations.

  17. Laboratory tests to identify patients at risk of early major adverse events: a prospective pilot study.

    Science.gov (United States)

    Kaufman, M; Bebee, B; Bailey, J; Robbins, R; Hart, G K; Bellomo, R

    2014-10-01

    To test whether commonly measured laboratory variables can identify surgical patients at risk of major adverse events (death, unplanned intensive care unit (ICU) admission or rapid response team (RRT) activation). We conducted a prospective observational study in a surgical ward of a university-affiliated hospital in a cohort of 834 surgical patients admitted for >24 h. We applied a previously validated multivariable model-derived risk assessment to each combined set of common laboratory tests to identify patients at risk. We compared the clinical course of such patients with that of control patients from the same ward who had blood tests but were identified as low risk. We studied 7955 batches and 73,428 individual tests in 834 patients (males 55%; average age 65.8 ± 17.6 years). Among these patients, 66 (7.9%) were identified as 'high risk'. High-risk patients were older (75.9 vs 61.8 years of age; P identify surgical ward patients at risk of early major adverse events. Further studies are needed to assess whether such identification system can be used to trigger interventions that help improve patient outcomes. © 2014 The Authors; Internal Medicine Journal © 2014 Royal Australasian College of Physicians.

  18. A controlled laboratory environment to study EO signal degradation due to underwater turbulence

    Science.gov (United States)

    Matt, Silvia; Hou, Weilin; Goode, Wesley; Liu, Guigen; Han, Ming; Kanaev, Andrey; Restaino, Sergio

    2015-05-01

    Temperature microstructure in the ocean can lead to localized changes in the index of refraction and can distort underwater electro-optical (EO) signal transmission. A similar phenomenon is well-known from atmospheric optics and generally referred to as "optical turbulence". Though turbulent fluctuations in the ocean distort EO signal transmission and can impact various underwater applications, from diver visibility to active and passive remote sensing, there have been few studies investigating the subject. To provide a test bed for the study of impacts from turbulent flows on underwater EO signal transmission, and to examine and mitigate turbulence effects, we set up a laboratory turbulence environment allowing the variation of turbulence intensity. Convective turbulence is generated in a large Rayleigh- Bénard tank and the turbulent flow is quantified using high-resolution Acoustic Doppler Velocimeter profilers and fast thermistor probes. The turbulence measurements are complemented by computational fluid dynamics simulations of convective turbulence emulating the tank environment. These numerical simulations supplement the sparse laboratory measurements. The numerical data compared well to the laboratory data and both conformed to the Kolmogorov spectrum of turbulence and the Batchelor spectrum of temperature fluctuations. The controlled turbulence environment can be used to assess optical image degradation in the tank in relation to turbulence intensity, as well as to apply adaptive optics techniques. This innovative approach that combines optical techniques, turbulence measurements and numerical simulations can help understand how to mitigate the effects of turbulence impacts on underwater optical signal transmission, as well as advance optical techniques to probe oceanic processes.

  19. U.S. Geological Survey geohydrologic studies and monitoring at the Idaho National Laboratory, southeastern Idaho

    Science.gov (United States)

    Bartholomay, Roy C.

    2017-09-14

    BackgroundThe U.S. Geological Survey (USGS) geohydrologic studies and monitoring at the Idaho National Laboratory (INL) is an ongoing, long-term program. This program, which began in 1949, includes hydrologic monitoring networks and investigative studies that describe the effects of waste disposal on water contained in the eastern Snake River Plain (ESRP) aquifer and the availability of water for long-term consumptive and industrial use. Interpretive reports documenting study findings are available to the U.S. Department of Energy (DOE) and its contractors; other Federal, State, and local agencies; private firms; and the public at https://id.water.usgs.gov/INL/Pubs/index.html. Information contained within these reports is crucial to the management and use of the aquifer by the INL and the State of Idaho. USGS geohydrologic studies and monitoring are done in cooperation with the DOE Idaho Operations Office.

  20. Laboratory Studies on Surface Sampling of Bacillus anthracis Contamination: Summary, Gaps, and Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Piepel, Gregory F.; Amidan, Brett G.; Hu, Rebecca

    2011-11-28

    This report summarizes previous laboratory studies to characterize the performance of methods for collecting, storing/transporting, processing, and analyzing samples from surfaces contaminated by Bacillus anthracis or related surrogates. The focus is on plate culture and count estimates of surface contamination for swab, wipe, and vacuum samples of porous and nonporous surfaces. Summaries of the previous studies and their results were assessed to identify gaps in information needed as inputs to calculate key parameters critical to risk management in biothreat incidents. One key parameter is the number of samples needed to make characterization or clearance decisions with specified statistical confidence. Other key parameters include the ability to calculate, following contamination incidents, the (1) estimates of Bacillus anthracis contamination, as well as the bias and uncertainties in the estimates, and (2) confidence in characterization and clearance decisions for contaminated or decontaminated buildings. Gaps in knowledge and understanding identified during the summary of the studies are discussed and recommendations are given for future studies.

  1. Does a dynamic chair increase office workers' movements? - Results from a combined laboratory and field study.

    Science.gov (United States)

    Grooten, Wilhelmus J A; Äng, Björn O; Hagströmer, Maria; Conradsson, David; Nero, Håkan; Franzén, Erika

    2017-04-01

    Dynamic chairs have the potential to facilitate movements that could counteract health problems associated with sedentary office work. This study aimed to evaluate whether a dynamic chair can increase movements during desk-based office work. Fifteen healthy subjects performed desk-based office work using a dynamic office chair and compared to three other conditions in a movement laboratory. In a field study, the dynamic office chair was studied during three working days using accelerometry. Equivocal results showed that the dynamic chair increased upper body and chair movements as compared to the conventional chair, but lesser movements were found compared to standing. No differences were found between the conditions in the field study. A dynamic chair may facilitate movements in static desk-based office tasks, but the results were not consistent for all outcome measures. Validation of measuring protocols for assessing movements during desk-based office work is warranted. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Open soundcard as a platform for practical, laboratory study of digital audio

    DEFF Research Database (Denmark)

    Dimitrov, Smilen; Serafin, Stefania

    2014-01-01

    This article investigates how lacking suitable platforms for laboratory exercises becomes a learning problem, limiting the practical experience students gain. In engineering education, laboratory demonstration difficulty of issues like real-time streaming in digital signal and audio processing is...

  3. Open soundcard as a platform for practical, laboratory study of digital audio

    DEFF Research Database (Denmark)

    Dimitrov, Smilen; Serafin, Stefania

    2014-01-01

    This article investigates how lacking suitable platforms for laboratory exercises becomes a learning problem, limiting the practical experience students gain. In engineering education, laboratory demonstration difficulty of issues like real-time streaming in digital signal and audio processing...

  4. Bioassay Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Bioassay Laboratory is an accredited laboratory capable of conducting standardized and innovative environmental testing in the area of aquatic ecotoxicology. The...

  5. HYDROMECHANICS LABORATORY

    Data.gov (United States)

    Federal Laboratory Consortium — Naval Academy Hydromechanics Laboratory The Naval Academy Hydromechanics Laboratory (NAHL) began operations in Rickover Hall in September 1976. The primary purpose...

  6. HYDROMECHANICS LABORATORY

    Data.gov (United States)

    Federal Laboratory Consortium — Naval Academy Hydromechanics LaboratoryThe Naval Academy Hydromechanics Laboratory (NAHL) began operations in Rickover Hall in September 1976. The primary purpose of...

  7. Measuring Meaningful Learning in the Undergraduate General Chemistry and Organic Chemistry Laboratories: A Longitudinal Study

    Science.gov (United States)

    Galloway, Kelli R.; Bretz, Stacey Lowery

    2015-01-01

    Understanding how students learn in the undergraduate chemistry teaching laboratory is an essential component to developing evidence-based laboratory curricula. The Meaningful Learning in the Laboratory Instrument (MLLI) was developed to measure students' cognitive and affective expectations and experiences for learning in the chemistry…

  8. Measuring Meaningful Learning in the Undergraduate General Chemistry and Organic Chemistry Laboratories: A Longitudinal Study

    Science.gov (United States)

    Galloway, Kelli R.; Bretz, Stacey Lowery

    2015-01-01

    Understanding how students learn in the undergraduate chemistry teaching laboratory is an essential component to developing evidence-based laboratory curricula. The Meaningful Learning in the Laboratory Instrument (MLLI) was developed to measure students' cognitive and affective expectations and experiences for learning in the chemistry…

  9. Study on Microbial Deposition and Contamination onto Six Surfaces Commonly Used in Chemical and Microbiological Laboratories.

    Science.gov (United States)

    Tamburini, Elena; Donegà, Valentina; Marchetti, Maria Gabriella; Pedrini, Paola; Monticelli, Cecilia; Balbo, Andrea

    2015-07-17

    The worktops in both chemical and microbiological laboratories are the surfaces most vulnerable to damage and exposure to contamination by indoor pollutants. The rate at which particles are deposited on indoor surfaces is an important parameter to determine human exposure to airborne biological particles. In contrast to what has been established for inorganic pollutants, no limit has been set by law for microbial contamination in indoor air. To our knowledge, a comparative study on the effect of surfaces on the deposition of microbes has not been carried out. An evaluation of the microbial contamination of worktop materials could be of crucial importance, both for safety reasons and for the reliability of tests and experiments that need to be carried out in non-contaminated environments. The aim of this study was to evaluate the overall microbial contamination (fungi, mesophilic and psychrophilic bacteria, staphylococci) on six widely used worktop materials in laboratories (glass, stainless steel, fine porcelain stoneware, post-forming laminate, high-performing laminate and enamel steel) and to correlate it with the characteristics of the surfaces. After cleaning, the kinetics of microbial re-contamination were also evaluated for all surfaces.

  10. Laboratory Scale Study of Activated Sludge Process in Jet Loop Reactor for Waste WaterTreatment

    Directory of Open Access Journals (Sweden)

    M. S. Patil

    2014-03-01

    Full Text Available The present study was undertaken to evaluate the feasibility of Activated Sludge Process (ASP for the treatment of synthetic wastewater and to develop a simple design criteria under local conditions.A laboratory scale Compact jet loop reactor model comprising of an aeration tank and final clarifier was used for this purpose.Settled synthetic wastewater was used as influent to the aeration tank. The Chemical Oxygen Demand (COD of the influent and effluent was measured to find process efficiency at various mixed liquorvolatile suspended solids (MLVSS and hydraulic retention time (θ. The results of the studydemonstrated that an efficiency of above 95% could be obtained for COD if the ASP is operated atan MLVSS concentration of 3000 mg/L keeping an aeration time of 1 hour.In the present investigation the preliminary studies were carried out in a lab scale Jet loop reactor made of glass. Synthetic waste water having a composition of 1000 mg/L mixed with other nutrients such as Urea, Primary and secondary Potassium phosphates, Magnesium sulfate, Iron chloriderequired for the bacteria was prepared in the laboratory and reduction in COD and the increase inSuspended Solids (SSand the Sludge Volume Index (SVI were determined.

  11. What have two decades of laboratory life-history evolution studies on Drosophila melanogaster taught us?

    Indian Academy of Sciences (India)

    N. G. Prasad; Amitabh Joshi

    2003-04-01

    A series of laboratory selection experiments on Drosophila melanogaster over the past two decades has provided insights into the specifics of life-history tradeoffs in the species and greatly refined our understanding of how ecology and genetics interact in life-history evolution. Much of what has been learnt from these studies about the subtlety of the microevolutionary process also has significant implications for experimental design and inference in organismal biology beyond life-history evolution, as well as for studies of evolution in the wild. Here we review work on the ecology and evolution of life-histories in laboratory populations of D. melanogaster, emphasizing how environmental effects on life-history-related traits can influence evolutionary change. We discuss life-history tradeoffs—many unexpected—revealed by selection experiments, and also highlight recent work that underscores the importance to life-history evolution of cross-generation and cross-life-stage effects and interactions, sexual antagonism and sexual dimorphism, population dynamics, and the possible role of biological clocks in timing life-history events. Finally, we discuss some of the limitations of typical selection experiments, and how these limitations might be transcended in the future by a combination of more elaborate and realistic selection experiments, developmental evolutionary biology, and the emerging discipline of phenomics.

  12. A review of toxicity studies on graphene-based nanomaterials in laboratory animals.

    Science.gov (United States)

    Ema, Makoto; Gamo, Masashi; Honda, Kazumasa

    2017-04-01

    We summarized the findings of toxicity studies on graphene-based nanomaterials (GNMs) in laboratory mammals. The inhalation of graphene (GP) and graphene oxide (GO) induced only minimal pulmonary toxicity. Bolus airway exposure to GP and GO caused acute and subacute pulmonary inflammation. Large-sized GO (L-GO) was more toxic than small-sized GO (S-GO). Intratracheally administered GP passed through the air-blood barrier into the blood and intravenous GO distributed mainly in the lungs, liver, and spleen. S-GO and L-GO mainly accumulated in the liver and lungs, respectively. Limited information showed the potential behavioral, reproductive, and developmental toxicity and genotoxicity of GNMs. There are indications that oxidative stress and inflammation may be involved in the toxicity of GNMs. The surface reactivity, size, and dispersion status of GNMs play an important role in the induction of toxicity and biodistribution of GNMs. Although this review paper provides initial information on the potential toxicity of GNMs, data are still very limited, especially when taking into account the many different types of GNMs and their potential modifications. To fill the data gap, further studies should be performed using laboratory mammals exposed using the route and dose anticipated for human exposure scenarios.

  13. Mixed waste landfill corrective measures study final report Sandia National Laboratories, Albuquerque, New Mexico.

    Energy Technology Data Exchange (ETDEWEB)

    Peace, Gerald (Jerry) L.; Goering, Timothy James (GRAM, Inc., Albuquerque, NM)

    2004-03-01

    The Mixed Waste Landfill occupies 2.6 acres in the north-central portion of Technical Area 3 at Sandia National Laboratories, Albuquerque, New Mexico. The landfill accepted low-level radioactive and mixed waste from March 1959 to December 1988. This report represents the Corrective Measures Study that has been conducted for the Mixed Waste Landfill. The purpose of the study was to identify, develop, and evaluate corrective measures alternatives and recommend the corrective measure(s) to be taken at the site. Based upon detailed evaluation and risk assessment using guidance provided by the U.S. Environmental Protection Agency and the New Mexico Environment Department, the U.S. Department of Energy and Sandia National Laboratories recommend that a vegetative soil cover be deployed as the preferred corrective measure for the Mixed Waste Landfill. The cover would be of sufficient thickness to store precipitation, minimize infiltration and deep percolation, support a healthy vegetative community, and perform with minimal maintenance by emulating the natural analogue ecosystem. There would be no intrusive remedial activities at the site and therefore no potential for exposure to the waste. This alternative poses minimal risk to site workers implementing institutional controls associated with long-term environmental monitoring as well as routine maintenance and surveillance of the site.

  14. Study on Microbial Deposition and Contamination onto Six Surfaces Commonly Used in Chemical and Microbiological Laboratories

    Directory of Open Access Journals (Sweden)

    Elena Tamburini

    2015-07-01

    Full Text Available The worktops in both chemical and microbiological laboratories are the surfaces most vulnerable to damage and exposure to contamination by indoor pollutants. The rate at which particles are deposited on indoor surfaces is an important parameter to determine human exposure to airborne biological particles. In contrast to what has been established for inorganic pollutants, no limit has been set by law for microbial contamination in indoor air. To our knowledge, a comparative study on the effect of surfaces on the deposition of microbes has not been carried out. An evaluation of the microbial contamination of worktop materials could be of crucial importance, both for safety reasons and for the reliability of tests and experiments that need to be carried out in non-contaminated environments. The aim of this study was to evaluate the overall microbial contamination (fungi, mesophilic and psychrophilic bacteria, staphylococci on six widely used worktop materials in laboratories (glass, stainless steel, fine porcelain stoneware, post-forming laminate, high-performing laminate and enamel steel and to correlate it with the characteristics of the surfaces. After cleaning, the kinetics of microbial re-contamination were also evaluated for all surfaces.

  15. Oxy-acetylene driven laboratory scale shock tubes for studying blast wave effects

    CERN Document Server

    Courtney, Michael

    2011-01-01

    Instrumentation is needed to produce realistic blast waves in a laboratory setting. This paper describes the development and characterization of oxy-acetylene driven, laboratory scale shock tubes for use in studying blast injury, candidate armor materials, and material properties at blast loading rates. The pressure-time profiles show a true shock front and exponential decay characteristic of blast waves and have relevant durations. The modular design includes shock tube diameters of 27 mm and 41 mm, and a selection of peak pressures from 204 kPa to 920 kPa can be produced by selection of the driver section diameter and placement of the test sample. Characterization studies of several driver/driven section combinations showed consistent results, with peak pressures having 0.8 - 6.9 percent uncertainty in the mean. This shock tube design provides a more realistic blast profile than current air-driven shock tubes. In addition, operation does not require specialized personnel or facilities like most blast-driven...

  16. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1992-07-01

    This report covers the second year of the 28 month grant current grant to Clarkson University to study the chemical and physical behavior of the polonium 218 atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and it dose to the cells in the respiratory tract are to be fully assessed. Two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical process that affect the progeny's atmospheric behavior and studies in actual indoor environments to develop a better assessment of the exposure of the occupants of that space to the size and concentration of the indoor radioactive aerosol. This report describes the progress toward achieving these objectives.

  17. Diagnostic studies on lithium-ion cells at Argonne National Laboratory: an overview

    Science.gov (United States)

    Abraham, Daniel P.

    2010-04-01

    High-power and high-energy lithium-ion cells are being studied at Argonne National Laboratory (Argonne) as part of the U.S. Department of Energy's FreedomCar and Vehicle Technologies (FCVT) program. Cells ranging in capacity from 1 mAh to 1Ah, and containing a variety of electrodes and electrolytes, are examined to determine suitable material combinations that will meet and exceed the FCVT performance, cost, and safety targets. In this article, accelerated aging of 18650-type cells, and characterization of components harvested from these cells, is described. Several techniques that include electrochemical measurements, analytical electron microscopy, and x-ray spectroscopy were used to study the various cell components. Data from these studies were used to identify the most likely contributors to property degradation and determine mechanisms responsible for cell capacity fade and impedance rise.

  18. Combining field work and laboratory work in the study of financial risk-taking.

    Science.gov (United States)

    Coates, John; Gurnell, Mark

    2017-02-04

    A contribution to a special issue on Hormones and Human Competition. Financial markets are periodically destabilized by bubbles and crashes during which investors display respectively what has been called "irrational exuberance" and "irrational pessimism". How can we best study these pathologies in competitive and risk-taking behaviours? In this article, we argue that a science of risk-taking and of the financial markets needs to draw heavily on physiology and especially endocrinology, due to their central roles in moderating human behaviour. Importantly, this science of competition and risk requires the same spectrum of research protocols as is found in mature biological and medical sciences, a spectrum running from field work conducted within financial institutions themselves to more controlled laboratory studies, which permit cause to be distinguished from effect. Such a spectrum of studies is especially important for translational behavioural science.

  19. Air flow and pollution in a real, heterogeneous urban street canyon: A field and laboratory study

    Science.gov (United States)

    Karra, Styliani; Malki-Epshtein, Liora; Neophytou, Marina K.-A.

    2017-09-01

    observed throughout the modelled street. The real-field observations and the laboratory measurements were compared. Overall, we found that lower variability in the background wind does not necessarily ensure a better agreement between the airflow velocity measured in the field and in the lab. In fact, it was observed that in certain cross sections, the airflow was more affected by the particular complex architectural features such as building extrusions and balconies, which were not represented in the simplified physical model tested in the laboratory, than by the real wind field variability. For wind speed comparisons the most favourable agreement (36.6% of the compared values were within a factor of 2) was found in the case of lowest wind variability and in the section with the most simple geometry where the physical lab model was most similar to the real street. For wind direction comparisons the most favourable agreement (45.5% of the compared values was within ±45°) was found in the case with higher wind variability but in the cross-sections with more homogeneous geometrical features. Street canyons are often simplified in research and are often modelled as homogenous symmetrical canyons under steady flow, for practical purposes; our study as a whole demonstrates that natural variability and heterogeneity play a large role in how pollution disperses throughout the street, and therefore further detail in models is vital to understand real world conditions.

  20. Laboratory study of low-β forces in arched, line-tied magnetic flux ropes

    Science.gov (United States)

    Myers, C. E.; Yamada, M.; Ji, H.; Yoo, J.; Jara-Almonte, J.; Fox, W.

    2016-11-01

    The loss-of-equilibrium is a solar eruption mechanism whereby a sudden breakdown of the magnetohydrodynamic force balance in the Sun's corona ejects a massive burst of particles and energy into the heliosphere. Predicting a loss-of-equilibrium, which has more recently been formulated as the torus instability, relies on a detailed understanding of the various forces that hold the pre-eruption magnetic flux rope in equilibrium. Traditionally, idealized analytical force expressions are used to derive simplified eruption criteria that can be compared to solar observations and modeling. What is missing, however, is a validation that these idealized analytical force expressions can be applied to the line-tied, low-aspect-ratio conditions of the corona. In this paper, we address this shortcoming by using a laboratory experiment to study the forces that act on long-lived, arched, line-tied magnetic flux ropes. Three key force terms are evaluated over a wide range of experimental conditions: (1) the upward hoop force; (2) the downward strapping force; and (3) the downward toroidal field tension force. First, the laboratory force measurements show that, on average, the three aforementioned force terms cancel to produce a balanced line-tied equilibrium. This finding validates the laboratory force measurement techniques developed here, which were recently used to identify a dynamic toroidal field tension force that can prevent flux rope eruptions [Myers et al., Nature 528, 526 (2015)]. The verification of magnetic force balance also confirms the low-β assumption that the plasma thermal pressure is negligible in these experiments. Next, the measured force terms are directly compared to corresponding analytical expressions. While the measured and analytical forces are found to be well correlated, the low-aspect-ratio, line-tied conditions in the experiment are found to both reduce the measured hoop force and increase the measured tension force with respect to analytical

  1. The Prosocial Effects of 3,4-methylenedioxymethamphetamine (MDMA): Controlled Studies in Humans and Laboratory Animals

    Science.gov (United States)

    Kamilar-Britt, Philip; Bedi, Gillinder

    2015-01-01

    Users of ±3,4-Methylenedioxymethamphetamine (MDMA; ‘ecstasy’) report prosocial effects such as sociability and empathy. Supporting these apparently unique social effects, data from controlled laboratory studies indicate that MDMA alters social feelings, information processing, and behavior in humans, and social behavior in rodents. Here, we review this growing body of evidence. In rodents, MDMA increases passive prosocial behavior (adjacent lying) and social reward while decreasing aggression, effects that may involve serotonin 1A receptor mediated oxytocin release interacting with vasopressin receptor 1A. In humans, MDMA increases plasma oxytocin and produces feelings of social affiliation. It decreases identification of negative facial expressions (cognitive empathy) and blunts responses to social rejection, while enhancing responses to others’ positive emotions (emotional empathy) and increasing social approach. Thus, consistent with drug folklore, laboratory administration of MDMA robustly alters social processing in humans and increases social approach in humans and animals. Effects are consistent with increased sociability, with mixed evidence about enhanced empathy. These neurobiologically-complex prosocial effects likely motivate recreational ecstasy use. PMID:26408071

  2. Internal Medicine Resident Engagement with a Laboratory Utilization Dashboard: Mixed Methods Study.

    Science.gov (United States)

    Kurtzman, Gregory; Dine, Jessica; Epstein, Andrew; Gitelman, Yevgenly; Leri, Damien; Patel, Miltesh S; Ryskina, Kyra

    2017-09-01

    The objective of this study was to measure internal medicine resident engagement with an electronic medical record-based dashboard providing feedback on their use of routine laboratory tests relative to service averages. From January 2016 to June 2016, residents were e-mailed a snapshot of their personalized dashboard, a link to the online dashboard, and text summarizing the resident and service utilization averages. We measured resident engagement using e-mail read-receipts and web-based tracking. We also conducted 3 hour-long focus groups with residents. Using grounded theory approach, the transcripts were analyzed for common themes focusing on barriers and facilitators of dashboard use. Among 80 residents, 74% opened the e-mail containing a link to the dashboard and 21% accessed the dashboard itself. We did not observe a statistically significant difference in routine laboratory ordering by dashboard use, although residents who opened the link to the dashboard ordered 0.26 fewer labs per doctor-patient-day than those who did not (95% confidence interval, -0.77 to 0.25; = 0 .31). While they raised several concerns, focus group participants had positive attitudes toward receiving individualized feedback delivered in real time. © 2017 Society of Hospital Medicine.

  3. Bioremediation of weathered petroleum hydrocarbon soil contamination in the Canadian High Arctic: laboratory and field studies.

    Science.gov (United States)

    Sanscartier, David; Laing, Tamsin; Reimer, Ken; Zeeb, Barbara

    2009-11-01

    The bioremediation of weathered medium- to high-molecular weight petroleum hydrocarbons (HCs) in the High Arctic was investigated. The polar desert climate, contaminant characteristics, and logistical constraints can make bioremediation of persistent HCs in the High Arctic challenging. Landfarming (0.3 m(3) plots) was tested in the field for three consecutive years with plots receiving very little maintenance. Application of surfactant and fertilizers, and passive warming using a greenhouse were investigated. The field study was complemented by a laboratory experiment to better understand HC removal mechanisms and limiting factors affecting bioremediation on site. Significant reduction of total petroleum HCs (TPH) was observed in both experiments. Preferential removal of compounds nC16 occurred, whereas in the field, TPH reduction was mainly limited to removal of compounds nC16 was observed in the fertilized field plots only. The greenhouse increased average soil temperatures and extended the treatment season but did not enhance bioremediation. Findings suggest that temperature and low moisture content affected biodegradation of HCs in the field. Little volatilization was measured in the laboratory, but this process may have been predominant in the field. Low-maintenance landfarming may be best suited for remediation of HCs compounds

  4. Accretion Shocks in the Laboratory: Using the OMEGA Laser to Study Star Formation

    Science.gov (United States)

    Young, R. P.; Kuranz, C. C.; Li, C. K.; Hartigan, P.; Froula, D.; Fiksel, G.; Ross, J. S.; Chang, P. Y.; Klein, S.; Zylstra, A.; Sio, H. W.; Liao, A.; Barnak, D.

    2016-10-01

    We present an on-going series of experiments using the OMEGA laser (Laboratory for Laser Energetics) to study star formation. Spectra of young stars show evidence of hotspots created when streams of accreting material impact at the surface of the star to create accretion shocks. These accretion shocks are poorly understood, as the surfaces of young stars cannot be spatially resolved. Our experiment series creates a scaled ``accretion shock'' on the OMEGA laser by driving a plasma jet (the ``accretion stream'') into a solid block (the ``stellar surface''), in the presence of a parallel magnetic field analogous to the star's local field. Thus far, visible image data from this experimental series either shows very thin accretion shocks forming or does not show them forming at all. We intend to present this data, provide possible explanations for why shocks may not have formed, and discuss potential improvements to the experimental design. This work is funded by the U.S. Department of Energy, through the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, Grant Number DE-NA0002956, and the National Laser User Facility Program, Grant Number DE-NA0002719.

  5. An Experimental Study of Laboratory Hybrid Power System with the Hydrogen Technologies

    Directory of Open Access Journals (Sweden)

    Daniel Minarik

    2014-01-01

    Full Text Available This paper presents very small laboratory hybrid photovoltaic-hydrogen power system. The system was primarily assembled to verify the operability of the control algorithms and practical deployment of available commercial hydrogen technologies that are directly usable for storage of electricity produced from renewable energy sources in a small island system. This energetic system was installed and tested in Laboratory of fuel cells that is located in the university campus of VSB-Technical University of Ostrava. The energetic system consists of several basic components: a photovoltaic field, accumulators bank, water commercial electrolyzer and compact fuel cell system. The weather conditions recorded in two different weeks as model weather and solar conditions are used as case studies to test the energetic system and the results for two different cases are compared each other. The results show and illustrate selected behaviour curves of the power system and also average energy storage efficiency for accumulation subsystem based on hydrogen technologies or at the energetic system embedded components. On the basis of real measurement and its evaluation the ideal parameters of the photovoltaic field were calculated as well as the hydrogen technologies for supposed purpose and the power requirements.

  6. Laboratory Study on Grout Injection for Improving Subgrade of Airfield Pavements

    Directory of Open Access Journals (Sweden)

    Teck Shang Goh

    2014-12-01

    Full Text Available This paper shares the authors’ experience of using low pressure grouting to improve the subgrade performance. The first part of the paper introduced a case history where low pressure grouting was applied in weakened subgrade of the active airport pavements in Kuala Lumpur International Airport (KLIA. The treated areas seemed to have been improved and only one of all eight treated areas had reoccurrence of depression. However, the performance of the treated area was difficult to be evaluated. The latter part of the paper investigated the effectiveness of grout injection through laboratory experiments. The laboratory equipment used for the grout injection tests included an injection mold and a steel tank of 1 m length x 0.6 m wide x 0.6 m depth for subgrade soil sample. Three grout types namely neat cement grout, fly ash cement grout, bentonite cement grout were used for this study. Six tests were conducted on sandy soil samples to examine the effect of grout type on the effectiveness of injection. The sandy soil was compacted to approximate 80 % of the maximum dry density. The injection pressure was fixed at 0.5 MPa. Insitu CBR test was also conducted to determine the strength of the grouted sample. The results showed that the fly ash cement grout could penetrate further than the neat cement grout; however its strength was lower than the neat cement grout.

  7. Precise Laboratory Measurement of LINR Frequencies Useful to Studies of Star and Planet Formation

    Science.gov (United States)

    Myers, Philip C.

    2004-01-01

    In March 2002, we began a program in laboratory spectroscopy to provide accurate molecular line frequencies essential to studies of the motions and abundances in star-froming dense cores and planet-forming circumstellar disks. The CN radical is one of the most important tracers of dynamical motions in protoplanetary disks around low mass pre-main sequence stars. The millimeter-wave spectrum of CN consists of rotational transitions every 113 GHz which are split into many resolved hyperfine components. Very narrow and fairly bright lines of SiO in the ground vibrational state have been observed in regions where protostellar outflows interact with the cold ambient gas. In support of future astronomical observations in these regions, 10 successive rotational lines in the ground vibrational state of Si0 between 86 and 500 GHz, and two lines near 800 GHz were measured in the laboratory to an accuracy of a few kHz. A negative glow discharge spectrometer that will allow the determination of accurate line frequencies of molecular ions has been constructed. We are presently modifying the method for cooling the magnetic field enhanced (negative glow) discharge cell to 77 K.

  8. A Study of Concept Mapping as an Instructional Intervention in an Undergraduate General Chemistry Calorimetry Laboratory

    Science.gov (United States)

    Stroud, Mary W.

    This investigation, rooted in both chemistry and education, considers outcomes occurring in a small-scale study in which concept mapping was used as an instructional intervention in an undergraduate calorimetry laboratory. A quasi-experimental, multiple-methods approach was employed since the research questions posed in this study warranted the use of both qualitative and quantitative perspectives and evaluations. For the intervention group of students, a convenience sample, post-lab concept maps, written discussions, quiz responses and learning surveys were characterized and evaluated. Archived quiz responses for non-intervention students were also analyzed for comparison. Students uniquely constructed individual concept maps containing incorrect, conceptually correct and "scientifically thin" calorimetry characterizations. Students more greatly emphasized mathematical relationships and equations utilized during the calorimetry experiment; the meaning of calorimetry concepts was demonstrated to a lesser extent.

  9. High altitude, a natural research laboratory for the study of cardiovascular physiology and pathophysiology.

    Science.gov (United States)

    Scherrer, Urs; Allemann, Yves; Jayet, Pierre-Yves; Rexhaj, Emrush; Sartori, Claudio

    2010-01-01

    High altitude constitutes an exciting natural laboratory for medical research. Although initially, the aim of high-altitude research was to understand the adaption of the organism to hypoxia and find treatments for altitude-related diseases, during the past decade or so, the scope of this research has broadened considerably. Two important observations led the foundation for the broadening of the scientific scope of high-altitude research. First, high-altitude pulmonary edema represents a unique model that allows studying fundamental mechanisms of pulmonary hypertension and lung edema in humans. Second, the ambient hypoxia associated with high-altitude exposure facilitates the detection of pulmonary and systemic vascular dysfunction at an early stage. Here, we will review studies that, by capitalizing on these observations, have led to the description of novel mechanisms underpinning lung edema and pulmonary hypertension and to the first direct demonstration of fetal programming of vascular dysfunction in humans.

  10. Study on fatty liver diagnosed by abdominal ultrasonography and clinical laboratory findings

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jeong Hwa [Cheju Halla College, Cheju (Korea, Republic of)

    2006-03-15

    The study obtained the following conclusions by making a comparative study on fatty liver diagnosed by abdominal ultrasonography and clinical laboratory findings. I surveyed the value of abdominal ultrasound in 400 patients without clinical symptoms at C Health Clinic Center, Seoul. Compare with blood pressure was high (systolic/diastolic) in 7.5%/4.5% on persons who were diagnosed fatty liver. At the time of the diagnosis, Total cholesterol level was increased in fatty liver patients, HDL-cholesterol level was high in fatty liver patients. And Trigryceride level was increased in fatty liver persons, LDL-cholesterol was high in fatty liver persons. SGOT level was increased in 5.5% on patients who were diagnosed fatty liver, 0% on persons who were normal and SGPT level was high in 29.5% on people who were diagnosed fatty liver, 0% on patients who were diagnosed normal.

  11. Polymyalgia rheumatica (PMR): clinical, laboratory, and immunofluorescence studies in 13 patients.

    Science.gov (United States)

    Shintani, Shuzo; Shiigai, Tatsuo; Matsui, Yoshiki

    2002-01-01

    Thirteen elderly patients with polymyalgia rheumatica (PMR) are presented. The clinical and laboratory findings suggest that many progressive symptoms are due to the non-specific inflammatory changes in various organs of the body, especially in muscles and joints. An immunofluorescence study of muscle biopsy specimens revealed IgG, IgA, and fibrinogen deposits in the perifascicular area of the perimysium. This finding suggests that immune complexes play a role in the pathogenesis of this condition and that the pathophysiology of PMR is an interstitial inflammatory process. We think that the inflammatory findings affecting the interstitial tissue of muscles in the immunofluorescence study are relatively specific to PMR, and will be affected by steroid treatment.

  12. Degradation of herbicides in shallow Danish aquifers - an integrated laboratory and field study

    DEFF Research Database (Denmark)

    Albrechtsen, Hans-Jørgen; Mills, M.; Aamand, J.

    2001-01-01

    , results were compared. Some herbicides were degraded under aerobic conditions (some phenoxy acids, DNOC and glyphosate) and others under aerobic conditions (other phenoxy acids, DNOC; there was some indication of atrazine transformation). Certain pesticides were not degraded in any investigations......Degradation of pesticides in aquifers has been evaluated based on a number of co-ordinated field and laboratory studies carried out in Danish aquifers. These studies included investigations of vertical and horizontal variability in degradation rates from the vadose zone to an aquifer, the effects...... (dichlobenil, the dichlobenil metabolite 2,6-dichlorobenzamide (BAM), bentazone, isoproturon, metarnitron and metsulfuron-methyl). The spatial variability was substantial, since hardly any of the investigated pesticides were degraded in all comparable samples. This means that it is very difficult to claim...

  13. Laboratory study on the molluscicidal effect of Earth Tec: an environmentally responsible copper sulfate product.

    Science.gov (United States)

    Ahmed, M M; Hady, H M; Salama, M M; el-Ghazali, S

    1994-08-01

    Studies were carried out, under laboratory conditions to evaluate the molluscicidal activity of Earth Tec on Biomphalaria alexandrina snails, the intermediate host of Schistosoma mansoni. Earth Tec is an environmentally responsible copper sulfate product manufactured and marketed as an algicide/bactericide with an active ingredient form of copper ion (Cu++). A single application, of 1 ppm of copper equivalent, for 24 hours caused 100% mortality rate of the snails. Exposure for 48 hours to 1 ppm and 2 weeks to 0.25 ppm caused mortality rates of 84% and 100% respectively. It was concluded that this chemical compound is a promising molluscicide. Field studies are ongoing and will be published in due time.

  14. Standardization of NIR microscopy spectra obtained from inter-laboratory studies by using a standardization cell

    Directory of Open Access Journals (Sweden)

    Fernández Pierna, JA.

    2013-01-01

    Full Text Available The near-infrared microscope (NIRM is an instrument that has demonstrated its great ability to detect contaminants not by analyzing a single spectrum but rather by analyzing hundreds or thousands of spectra from individual particles, while at the same time being a non-destructive and easy-to-use technique. It has been used for the detection of meat-and-bone meal (MBM in compound feeds within the context of the European bovine spongiform encephalopathy (BSE; commonly known as "mad cow disease" crisis. This study describes, for the first time, an application of NIRM instrument standardization using a measurement cell in an inter-laboratory study conducted within the framework of a qualitative determination of animal proteins in compound feeds, based on spectra obtained with eight instruments. The standardization cell was assessed for its ability to produce good optical matching of the instruments and/or to evaluate instrument performance.

  15. Quantification of rock heterogeneities by structural geological field studies combined with laboratory analyses

    Science.gov (United States)

    Reyer, Dorothea; Afsar, Filiz; Philipp, Sonja

    2013-04-01

    Heterogeneous rock properties in terms of layering and complex infrastructure of fault zones are typical in sedimentary successions. The knowledge of in-situ mechanical rock properties is crucial for a better understanding of processes such as fracturing and fluid transport in fractured reservoirs. To estimate in situ rock properties at different depths it is important to understand how rocks from outcrops differ from rocks at depth, for example due to alteration and removal of the overburden load. We aim at quantifying these properties by performing structural geological field studies in outcrop analogues combined with laboratory analyses of outcrop samples and drill-cores. The field studies focus on 1) fault zone infrastructure and 2) host rock fracture systems in two different study areas with different lithologies, the North German and the Bristol Channel Basin. We analyse quantitatively the dimension, geometry, persistence and connectivity of fracture systems. The field studies are complemented by systematic sampling to obtain the parameters Young's modulus, compressive and tensile strengths and elastic strain energy (also referred to as destruction work) from which we estimate rock and fracture toughnesses. The results show that in rocks with distinctive layering fractures are often restricted to individual layers, that is, stratabound. The probability of arrest seems to depend on the stiffness contrast between two single layers as well as on the thickness of the softer layer. The results also show that there are clear differences between fault zones in the different lithologies in terms of damage zone thicknesses and fracture system parameters. The results of laboratory analyses show that the mechanical properties vary considerably and for many samples there are clear directional differences. That is, samples taken perpendicular to layering commonly have higher stiffnesses and strengths than those taken parallel to layering. We combine the results of

  16. A study of social interaction and teamwork in reformed physics laboratories

    Science.gov (United States)

    Gresser, Paul W.

    It is widely accepted that, for many students, learning can be accomplished most effectively through social interaction with peers, and there have been many successes in using the group environment to improve learning in a variety of classroom settings. What is not well understood, however, are the dynamics of student groups, specifically how the students collectively apprehend the subject matter and share the mental workload. This research examines recent developments of theoretical tools for describing the cognitive states of individual students: associational patterns such as epistemic games and cultural structures such as epistemological framing. Observing small group interaction in authentic classroom situations (labs, tutorials, problem solving) suggests that these tools could be effective in describing these interactions. Though conventional wisdom tells us that groups may succeed where individuals fail, there are many reasons why group work may also run into difficulties, such as a lack or imbalance of knowledge, an inappropriate mix of learning styles, or a destructive power arrangement. This research explores whether or not inconsistent epistemological framing among group members can also be a cause of group failure. Case studies of group interaction in the laboratory reveal evidence of successful groups employing common framing, and unsuccessful groups failing from lack of a shared frame. This study was conducted in a large introductory algebra-based physics course at the University of Maryland, College Park, in a laboratory designed specifically to foster increased student interaction and cooperation. Videotape studies of this environment reveal that productive lab groups coordinate their efforts through a number of locally coherent knowledge-building activities, which are described through the framework of epistemic games. The existence of these epistemic games makes it possible for many students to participate in cognitive activities without a

  17. Toxicology Studies on Lewisite and Sulfur Mustard Agents: Two-Generation Reproduction Study of Sulfur Mustard (HD) in Rats

    Science.gov (United States)

    1989-09-30

    ACO6.76RLO 78&0 1ECURITY CLASIFICATION or. TWIS AfE REPORT DOCUMENTATION PAGE OIN 7Ŝ I&. REPORT SECURITY CLASSIFICATION 1b. RESTRICTIVE MARKINGS...compounds (Wheeler, 1962). These chemicals react rapidly with certain functional groups of proteins (OH, NH2 , and SH) to alter their metabolic activity. In

  18. Understanding the migratory orientation program of birds: extending laboratory studies to study free-flying migrants in a natural setting.

    Science.gov (United States)

    Thorup, Kasper; Holland, Richard A; Tøttrup, Anders P; Wikelski, Martin

    2010-09-01

    For many years, orientation in migratory birds has primarily been studied in the laboratory. Although a laboratory-based setting enables greater control over environmental cues, the laboratory-based findings must be confirmed in the wild in free-flying birds to be able to fully understand how birds orient during migration. Despite the difficulties associated with following free-flying birds over long distances, a number of possibilities currently exist for tracking the long distance, sometimes even globe-spanning, journeys undertaken by migrating birds. Birds fitted with radio transmitters can either be located from the ground or from aircraft (conventional tracking), or from space. Alternatively, positional information obtained by onboard equipment (e.g., GPS units) can be transmitted to receivers in space. Use of these tracking methods has provided a wealth of information on migratory behaviors that are otherwise very difficult to study. Here, we focus on the progress in understanding certain components of the migration-orientation system. Comparably exciting results can be expected in the future from tracking free-flying migrants in the wild. Use of orientation cues has been studied in migrating raptors (satellite telemetry) and thrushes (conventional telemetry), highlighting that findings in the natural setting may not always be as expected on the basis of cage-experiments. Furthermore, field tracking methods combined with experimental approaches have finally allowed for an extension of the paradigmatic displacement experiments performed by Perdeck in 1958 on the short-distance, social migrant, the starling, to long-distance migrating storks and long-distance, non-socially migrating passerines. Results from these studies provide fundamental insights into the nature of the migratory orientation system that enables experienced birds to navigate and guide inexperienced, young birds to their species-specific winter grounds.

  19. Two Generations of Maternal Alcohol Abuse: Impact on Cognitive Levels in Mothers and Their Children

    Science.gov (United States)

    Dumaret, Annick-Camille; Cousin, Melanie; Titran, Maurice

    2010-01-01

    Transgenerational effects of alcohol on mothers' and children's intellectual functioning has been examined in 22 families from very deprived environments. Their psychosocial outcomes and IQ level were evaluated in a follow-up study on average seven years after they left the support group of a day-care centre for young children; school data were…

  20. Consequences of filial support for two generations: a narrative and quantitative review

    NARCIS (Netherlands)

    Merz, E.-M.; Schulze, H.-J.; Schuengel, C.

    2010-01-01

    This narrative and quantitative review synthesizes findings from 55 (N = 54,550) studies on the association between providing support to elderly parents and well-being of adult children as well as well-being of parents, in an endeavor to determine the prevailing direction of effects, magnitude of ef

  1. Consequences of Filial Support for Two Generations: A Narrative and Quantitative Review

    NARCIS (Netherlands)

    Merz, E.M.; Schulze, H.; Schuengel, C.

    2010-01-01

    This narrative and quantitative review synthesizes findings from 55 (N = 54,550) studies on the association between providing support to elderly parents and well-being of adult children as well as well-being of parents, in an endeavor to determine the prevailing direction of effects, magnitude of ef

  2. Two Generations of Maternal Alcohol Abuse: Impact on Cognitive Levels in Mothers and Their Children

    Science.gov (United States)

    Dumaret, Annick-Camille; Cousin, Melanie; Titran, Maurice

    2010-01-01

    Transgenerational effects of alcohol on mothers' and children's intellectual functioning has been examined in 22 families from very deprived environments. Their psychosocial outcomes and IQ level were evaluated in a follow-up study on average seven years after they left the support group of a day-care centre for young children; school data were…

  3. Using Laboratory Experimental Auctions in Marketing Research: A Case Study of New Packaging for Fresh Beef

    OpenAIRE

    Elizabeth Hoffman; Menkhaus, Dale J.; Dipankar Chakravarti; Field, Ray A.; Whipple, Glen D.

    1993-01-01

    This paper illustrates the use of laboratory experimental auctions in a pretest market research program for new products. We review the experimental auctions literature, discuss the range of auction mechanisms available and present the advantages and disadvantages of using a particular mechanism for a laboratory pretest market. We then present a step-by-step example of how a theoretically incentive compatible auction mechanism (fifth-price, sealed-bid) was used in a laboratory pretest market ...

  4. A comparative study of different diets to optimize cultivation of Hyalella azteca in the laboratory.

    Science.gov (United States)

    Fracácio, Renata; Dias, Geisa Soares; Zagatto, Pedro Antônio; Bidinotto, Paulo Maurício; Silva, Paulo

    2011-09-01

    The aim of this study was to assess the influence of four diets on the laboratory cultivation of H. azteca, seeking to improve production of young specimens through reduced mortality and better growth and number of offspring per couple. The best diet was composed of a mixture of diluted commercial fish food, diluted yeast and primrose oil, associated with fish food flakes containing spirulina. With this diet the maximum mortality was 25 percent (at the end of 28 days), the average number of offspring/couple was 11.4 ± 2.8 (at the end of twelve days) and the peak weight and length of the males (at the end of 40 days) were 0.930 μg and 5.26 ± 1.1mm, respectively.

  5. Laboratory Study Of Magnetic Reconnection With A Density Asymmetry Across The Current Sheet

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Joseph; Yamada, Massaaki; Ji, Hantao; Meyers,, Clayton E.; Jara-Almonte,; Chen, Li-Jen

    2014-04-18

    The effects of an upstream density asymmetry on magnetic reconnection are studied systematically in a laboratory plasma. Despite a significant upstream density asymmetry of up to 10, the reconnecting magnetic field pro file is not signifi cantly changed. On the other hand, the out-of-plane magnetic field profile is considerably modified; it is almost bipolar in structure with the density asymmetry, as compared to the quadrupolar structure in the symmetric configuration. The in-plane ion flow pattern and the electrostatic potential pro file are also affected by the density asymmetry. Strong bulk electron heating is observed near the low-density-side separatrix together with electromagnetic fluctuations in the lower hybrid frequency range. The dependence of the ion outflow and reconnection electric field on the density asymmetry is measured and compared with theoretical expectations.

  6. Study of single muons with the Large Volume Detector at Gran Sasso Laboratory

    CERN Document Server

    Aglietta, M; Antonioli, P; Badino, G; Bari, G; Basile, M; Berezinsky, Veniamin Sergeevich; Bersani, F; Bertaina, M; Bertoni, R; Bruni, G; Cara Romeo, G; Castagnoli, C; Castellina, A; Chiavassa, A; Chinellato, J A; Cifarelli, Luisa; Cindolo, F; Contin, A; Dadykin, V L; Dos Santos, L G; Enikeev, R I; Fulgione, W; Galeotti, P; Ghia, P; Giusti, P; Gómez, F; Granella, R; Grianti, F; Gurentsov, V I; Iacobucci, G; Inoue, N; Kemp, E; Khalchukov, F F; Korolkova, E V; Korchaguin, P V; Korchaguin, V B; Kudryavtsev, V A; Luvisetto, Marisa L; Malguin, A S; Massam, Thomas; Mengotti-Silva, N; Morello, C; Nania, R; Navarra, G; Periale, L; Pesci, A; Picchi, P; Pless, I A; Ryasny, V G; Ryazhskaya; Saavedra, O; Saitoh, K; Sartorelli, G; Selvi, M; Taborgna, N; Talochkin, P; Trinchero, G C; Tsuji, S; Turtelli, A; Vallania, P; Vernetto, S; Vigorito, C; Votano, L; Wada, T; Weinstein, R; Widgoff, M; Yakushev, V F; Yamamoto, I; Zatsepin, G T; Zichichi, A

    2003-01-01

    The present study is based on the sample of about 3 mln single muons observed by LVD at underground Gran Sasso Laboratory during 36500 live hours from June 1992 to February 1998. We have measured the muon intensity at slant depths from 3 km w.e. to 20 km w.e. Most events are high energy downward muons produced by meson decay in the atmosphere. The analysis of these muons has revealed the power index of pion and kaon spectrum: 2.76 \\pm 0.05. The reminders are horizontal muons produced by the neutrino interactions in the rock surrounding LVD. The value of this flux is obtained. The results are compared with Monte Carlo simulations and the world data.

  7. Laboratory Study of High Temperature Corrosion in Straw-fired Power Plants

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Maahn, Ernst emanuel

    1997-01-01

    The components contributing to corrosion, HCl(g)SO2(g), KCl and K2SO4 were studied in the laboratory for Sandvik 8LR30 and Sanicro 28. The influence of HCl and SO2 was investigated at 600C material temperature and 600/800C flue gas temperature at time intervals up to 300 hours. The influence of ash...... deposits in air was examined at 525C-700C. Finally exposures were undertaken combining the aforementioned aggressive gas environment with the ash deposits. Thus the corrosion potential of individual components were evaluated and also whether they had a synergistic, antagonistic or additive effect on one...... another to influence the overall corrosion rate....

  8. An apparatus for studying spallation neutrons in the Aberdeen Tunnel laboratory

    CERN Document Server

    Blyth, S C; Chen, X C; Chu, M C; Hahn, R L; Ho, T H; Hsiung, Y B; Hu, B Z; Kwan, K K; Kwok, M W; Kwok, T; Lau, Y P; Lee, K P; Leung, J K C; Leung, K Y; Lin, G L; Lin, Y C; Luk, K B; Luk, W H; Ngai, H Y; Ngan, S Y; Pun, C S J; Shih, K; Tam, Y H; Tsang, R H M; Wang, C H; Wong, C M; Wong, H L; Wong, H H C; Wong, K K; Yeh, M

    2013-01-01

    In this paper, we describe the design, construction and performance of an apparatus installed in the Aberdeen Tunnel laboratory in Hong Kong for studying spallation neutrons induced by cosmic-ray muons under a vertical rock overburden of 611 meter water equivalent (m.w.e.). The apparatus comprises of six horizontal layers of plastic-scintillator hodoscopes for determining the direction and position of the incident cosmic-ray muons. Sandwiched between the hodoscope planes is a neutron detector filled with 650 kg of liquid scintillator doped with about 0.06% of Gadolinium by weight for improving the e?ciency of detecting the spallation neutrons. Performance of the apparatus is also presented.

  9. Fossil Galaxy Groups -- Ideal Laboratories for Studying the Effects of AGN Heating

    CERN Document Server

    Jetha, Nazirah N; Raychaudhury, Somak; Sengupta, Chandreyee; Hardcastle, Martin

    2009-01-01

    We present the first of a sample of fossil galaxy groups with pre-existing Chandra and/or XMM-Newton X-ray observations and new or forthcoming low frequency GMRT data -- RXJ1416.4+2315 (z=0.137). Fossil galaxy groups are ideal laboratories for studying feedback mechanisms and how energy injection affects the IGM, since due to the lack of recent merging activity, we expect the IGM to be relatively pristine and affected only by any AGN activity that has occurred in the group. Our Chandra X-ray observations reveal features resembling AGN-inflated bubbles, whilst our GMRT radio data show evidence of extended emission from the central AGN that may be filling the bubble. This has enabled us to estimate the work done by the central AGN, place limits on the rates of energy injection and discuss the nature of the plasma filling the bubble.

  10. Simulating the photometric study of pulsating white dwarf stars in the physics laboratory

    CERN Document Server

    Chote, Paul

    2015-01-01

    We have designed a realistic simulation of astronomical observing using a relatively low-cost commercial CCD camera and a microcontroller-based circuit that drives LEDs inside a light-tight box with time-varying intensities. As part of a laboratory experiment, students can acquire sequences of images using the camera, and then perform data analysis using a language such as MATLAB or Python to: (a) extract the intensity of the imaged LEDs, (b) perform basic calibrations on the time-series data, and (c) convert their data into the frequency domain where they can then identify the frequency structure. The primary focus is on studying light curves produced by the pulsating white dwarf stars. The exercise provides an introduction to CCD observing, a framework for teaching concepts in numerical data analysis and Fourier techniques, and connections with the physics of white dwarf stars.

  11. Environmental Risk Assessment of antimicrobials applied in veterinary medicine-A field study and laboratory approach.

    Science.gov (United States)

    Slana, Marko; Dolenc, Marija Sollner

    2013-01-01

    The fate and environmental risk of antimicrobial compounds of different groups of veterinary medicine pharmaceuticals (VMP's) have been compared. The aim was to demonstrate a correlation between the physical and chemical properties of active compounds and their metabolism in target animals, as well as their fate in the environment. In addition, the importance of techniques for manure management and agricultural practice and their influence on the fate of active compounds is discussed. The selected active compounds are shown to be susceptible to at least one environmental factor (sun, water, bacterial or fungal degradation) to which they are exposed during their life cycle, which contributes to its degradation. Degradation under a number of environmental factors has also to be considered as authentic information additional to that observed in the limited conditions in laboratory studies and in Environmental Risk Assessment calculations. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Mars Science Laboratory Launch-Arrival Space Study: A Pork Chop Plot Analysis

    Science.gov (United States)

    Cianciolo, Alicia Dwyer; Powell, Richard; Lockwood, Mary Kae

    2006-01-01

    Launch-Arrival, or "pork chop", plot analysis can provide mission designers with valuable information and insight into a specific launch and arrival space selected for a mission. The study begins with the array of entry states for each pair of selected Earth launch and Mars arrival dates, and nominal entry, descent and landing trajectories are simulated for each pair. Parameters of interest, such as maximum heat rate, are plotted in launch-arrival space. The plots help to quickly identify launch and arrival regions that are not feasible under current constraints or technology and also provide information as to what technologies may need to be developed to reach a desired region. This paper provides a discussion of the development, application, and results of a pork chop plot analysis to the Mars Science Laboratory mission. This technique is easily applicable to other missions at Mars and other destinations.

  13. FY 1995 separation studies for liquid low-level waste treatment at Oak Ridge National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Bostick, D.T.; Arnold, W.D.; Burgess, M.W. [and others

    1995-01-01

    During FY 1995, studies were continued to develop improved methods for centralized treatment of liquid low-level waste (LLLW) at Oak Ridge National Laboratory (ORNL). Focus in this reporting period was on (1) identifying the parameters that affect the selective removal of {sup 90}Sr and {sup 137}Cs, two of the principal radioactive contaminants expected in the waste; (2) validating the effectiveness of the treatment methods by testing an ac Melton Valley Storage Tank (MVST) supernate; (3) evaluating the optimum solid/liquid separation techniques for the waste; (4) identifying potential treatment methods for removal of technetium from LLLW; and (5) identifying potential methods for stabilizing the high-activity secondary solid wastes generated by the treatment.

  14. Experimental study of subcritical laboratory magnetized collisionless shocks using a laser-driven magnetic piston

    Science.gov (United States)

    Schaeffer, D. B.; Everson, E. T.; Bondarenko, A. S.; Clark, S. E.; Constantin, C. G.; Winske, D.; Gekelman, W.; Niemann, C.

    2015-11-01

    Recent experiments at the University of California, Los Angeles have successfully generated subcritical magnetized collisionless shocks, allowing new laboratory studies of shock formation relevant to space shocks. The characteristics of these shocks are compared with new data in which no shock or a pre-shock formed. The results are consistent with theory and 2D hybrid simulations and indicate that the observed shock or shock-like structures can be organized into distinct regimes by coupling strength. With additional experiments on the early time parameters of the laser plasma utilizing Thomson scattering, spectroscopy, and fast-gate filtered imaging, these regimes are found to be in good agreement with theoretical shock formation criteria.

  15. Stressful task increases drive for thinness and bulimia: a laboratory study.

    Directory of Open Access Journals (Sweden)

    Sandra eSassaroli

    2015-05-01

    Full Text Available The scientific literature has suggested that stress undergirds the development of eating disorders (ED. Therefore, this study explored whether laboratory induced stress increases self-reported drive for thinness and bulimic symptoms measured via self-report. The relationship between control, perfectionism, stress, and cognition related to ED was examined using correlational methodology. 86 participants completed an experimental task using a personal computer. All individuals completed a battery of tests before and after the stressful task. Analyses showed a significant statistical increase in average scores on the drive for thinness and bulimia measured before and after a stressful task, and path analysis revealed two different cognitive models for the mechanism leading to drive for thinness and bulimia. These findings suggest that stress is an important factor in the development of the drive for thinness and bulimia.

  16. Laboratory studies of polycyclic aromatic hydrocarbons: the search for interstellar candidates

    CERN Document Server

    Joblin, C; Simon, A; Mulas, G

    2009-01-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are considered as a major constituent of interstellar dust. They have been proposed as the carriers of the Aromatic Infrared Bands (AIBs) observed in emission in the mid-IR. They likely have a significant contribution to various features of the extinction curve such as the 220 nm bump,the far-UV rise and the diffuse interstellar bands. Emission bands are also expected in the far-IR, which are better fingerprints of molecular identity than the AIBs. They will be searched for with the Herschel Space Observatory. Rotational emission is also expected in the mm range for those molecules which carry significant dipole moments. Despite spectroscopic studies in the laboratory, no individual PAH species could be identified. This emphasises the need for an investigation on where interstellar PAHs come from and how they evolve due to environmental conditions: ionisation and dissociation upon UV irradiation, interactions with electrons, gas and dust. There is also evidence for PAH ...

  17. Epidemiological characteristics and laboratory diagnosis of fungal keratitis. A three-year study

    Directory of Open Access Journals (Sweden)

    Bharathi Jayahar

    2003-01-01

    Full Text Available Purpose: To study the epidemiological characteristics and laboratory diagnosis of fungal keratitis seen at a tertiary eye care referral centre in South India. Methods: A retrospective review of all culture-proven fungal keratitis seen over a 3-year period, September 1999 through August 2002. Results: Fungal aetiology were confirmed in1095(34.4% of 3183 corneal ulcers. The predominant fungal species isolated was Fusarium spp (471; 42.82% followed by Aspergillus spp (286; 26%. Males (712; 65.08% were more often affected (P< 0.0001. A large proportion of the patients (732; 66.85% were in the younger age group (21 to 50 years. A majority (879; 80.27% came from rural areas (P Conclusion: Agricultural activity and related ocular trauma were principal causes of mycotic keratitis. A potassium hydroxide (KOH wet mount preparation is a simple, and sensitive, method for diagnosis.

  18. Phthalocyanine identification in paintings by reflectance spectroscopy. A laboratory and in situ study

    Science.gov (United States)

    Poldi, G.; Caglio, S.

    2013-06-01

    The importance of identifying pigments using non invasive (n.i.) analyses has gained increasing importance in the field of spectroscopy applied to art conservation and art studies. Among the large set of pigments synthesized and marketed during 20th century, surely phthalocyanine blue and green pigments occupy an important role in the field of painting (including restoration) and printing, thanks to their characteristics like brightness and fastness. This research focused on the most used phthalocyanine blue (PB15:1 and PB15:3) and green pigments (PG7), and on the possibility to identify these organic compounds using a methodology like reflectance spectroscopy in the UV, visible and near IR range (UV-vis-NIR RS), performed easily through portable instruments. Laboratory tests and three examples carried out on real paintings are discussed.

  19. Stressful task increases drive for thinness and bulimia: a laboratory study

    Science.gov (United States)

    Sassaroli, Sandra; Fiore, Francesca; Mezzaluna, Clarice; Ruggiero, Giovanni Maria

    2015-01-01

    The scientific literature has suggested that stress undergirds the development of eating disorders (ED). Therefore, this study explored whether laboratory induced stress increases self-reported drive for thinness and bulimic symptoms measured via self-report. The relationship between control, perfectionism, stress, and cognition related to ED was examined using correlational methodology. Eighty-six participants completed an experimental task using a personal computer (PC). All individuals completed a battery of tests before and after the stressful task. Analyses showed a significant statistical increase in average scores on the drive for thinness and bulimia measured before and after a stressful task, and path analysis revealed two different cognitive models for the mechanism leading to drive for thinness and bulimia. These findings suggest that stress is an important factor in the development of the drive for thinness and bulimia. PMID:25999901

  20. Review of concepts useful for maintaining quality of male reproductive field samples for laboratory study

    Science.gov (United States)

    Jenkins, Jill A.

    2011-01-01

    Investigations into cellular and molecular characteristics of male gametes obtained from fish in natural ecosystems require careful sample handling and shipping in order to minimize artifacts. Maintaining sample integrity engenders confident assessments of ecosystem health, whereby animal condition is often reflected by gamete biomarkers - indicators that respond in measurable ways to changes. A number of our investigations have addressed the hypothesis that biomarkers from fish along a pollution gradient are reflective of site location. Species biology and the selected biological endpoints direct choice of parameters such as: temperature, buffer osmolality, time in transit, fixation, cryoprotectants, protease inhibition, and antibiotic inclusion in extender. This paper will highlight case studies, and outline parameters and thoughts on approaches for use by field and laboratory researchers.

  1. Comparison of four types of diet using clinical, laboratory and psychological studies.

    Science.gov (United States)

    Lockie, A H; Carlson, E; Kipps, M; Thomson, J

    1985-07-01

    Thirty-seven people of different dietary habits-vegans, ovolactovegetarians, whole-food omnivores and average omnivores-were studied using nine-day weighed food intakes, clinical and laboratory assessments, standard psychology questionnaires, measurements of urinary cortisol and catecholamine levels and questionnaires on life-style and health factors. The vegan diet most clearly approximated current thinking on diet, as expressed in the NACNE Report, but was deficient in vitamin D, riboflavin, and vitamin B12. Cholesterol levels were significantly higher in both diet and serum in all groups compared with the vegans. There was no significant difference in social background, money spent on food, exercise, smoking, stress levels or psychological parameters between groups.

  2. A laboratory study of the subjective response to helicopter blade-slap noise

    Science.gov (United States)

    Shepherd, K. P.

    1978-01-01

    The test stimuli recorded during a recent field study consisted of 16 sounds, each presented at 4 peak noise levels. Two helicopters and a fixed-wing aircraft were used. The impulsive characteristics of one helicopter were varied by operating at different rotor speeds, whereas the other helicopter, the noise of which was dominated by the tail rotor, displayed little variation in blade-slap noise. Thirty-two subjects made noisiness judgments on a continuous, 11 point, numerical scale. Preliminary results indicate that proposed impulsiveness corrections provide no significant improvement in the noisiness predictive ability of Effective Perceived Noise Levels (EPNL). For equal EPNL, the two categories of helicopter stimuli, one of which was far more impulsive than the other, showed no difference in judged noisiness. Examination of the physical characteristics of the sounds presented in the laboratory highlighted the difficulty of reproducing acoustical signals with high-crest factors.

  3. Family Resources in Two Generations and School Readiness among Children of Teen Parents

    Science.gov (United States)

    Fomby, Paula; James-Hawkins, Laurie; Mollborn, Stefanie

    2015-01-01

    Overall, children born to teen parents experience disadvantaged cognitive achievement at school entry compared to children born to older parents. However, within this population there is variation, with a significant fraction of teen parents’ children acquiring adequate preparation for school entry during early childhood. We ask whether the family background of teen parents explains this variation. We use data on children born to teen mothers from three waves of the Early Childhood Longitudinal Study-Birth Cohort (N~700) to study the association of family background with children's standardized reading and mathematics achievement scores at kindergarten entry. When neither maternal grandparent has completed high school, children's scores on standardized assessments of math and reading achievement are one-quarter to one-third of a standard deviation lower compared to families where at least one grandparent finished high school. This association is net of teen mothers’ own socioeconomic status in the year prior to children's school entry. PMID:26806989

  4. Through The Looking Glass: Laboratory Studies Of Calcium Bearing Amorphous Pyroxenes

    Science.gov (United States)

    Wheeler, Jordan D.

    2011-01-01

    Many astrophysical environments exhibit spectral features around 10µm and 18µm that have long been attributed to amorphous (glassy) silicates. However existing laboratory spectral data for amorphous silicates do not cover a wide enough compositional range to allow astronomers to interpret their observations without large uncertainty. In particular, while magnesium-rich silicates have been studied extensively, the effect of some other likely components (e.g. calcium, aluminium) have been largely neglected, even though these elements are expected to play a major role in dust condensation. We present laboratory spectra for a series of 8 glasses, produced by quenching silicate melts of calcium-bearing pyroxene composition. The samples range from the Mg end-member (enstatite; MgSiO3) to the Ca end-member (wollastonite; CaSiO3). The halfway composition corresponds to the mineral diopside (CaMgSi2O6), which has previously been proposed to explain observed spectral features. CaMgSi2O6 glass has a much broader 10µm peak than Mg2Si2O6 glass, due to the more varied bonding environments resulting from two different network modifying cations, and its peak extends to longer wavelengths, consistent with the greater mass of Ca. The presence of other elements is likewise expected to result in broader features and subtle changes in peak position. In addition to a systematic study of the effect of Ca substitution for Mg, we present some more complex glasses that include Na, Al and Fe as minor constituents. In addition we present measurements of the viscosity of these glasses to determine the glass transition temperature (Tg), which provides an important constraint on the thermal history of observed glassy silicate.

  5. Iterative Outlier Removal: A Method for Identifying Outliers in Laboratory Recalibration Studies.

    Science.gov (United States)

    Parrinello, Christina M; Grams, Morgan E; Sang, Yingying; Couper, David; Wruck, Lisa M; Li, Danni; Eckfeldt, John H; Selvin, Elizabeth; Coresh, Josef

    2016-07-01

    Extreme values that arise for any reason, including those through nonlaboratory measurement procedure-related processes (inadequate mixing, evaporation, mislabeling), lead to outliers and inflate errors in recalibration studies. We present an approach termed iterative outlier removal (IOR) for identifying such outliers. We previously identified substantial laboratory drift in uric acid measurements in the Atherosclerosis Risk in Communities (ARIC) Study over time. Serum uric acid was originally measured in 1990-1992 on a Coulter DACOS instrument using an uricase-based measurement procedure. To recalibrate previous measured concentrations to a newer enzymatic colorimetric measurement procedure, uric acid was remeasured in 200 participants from stored plasma in 2011-2013 on a Beckman Olympus 480 autoanalyzer. To conduct IOR, we excluded data points >3 SDs from the mean difference. We continued this process using the resulting data until no outliers remained. IOR detected more outliers and yielded greater precision in simulation. The original mean difference (SD) in uric acid was 1.25 (0.62) mg/dL. After 4 iterations, 9 outliers were excluded, and the mean difference (SD) was 1.23 (0.45) mg/dL. Conducting only one round of outlier removal (standard approach) would have excluded 4 outliers [mean difference (SD) = 1.22 (0.51) mg/dL]. Applying the recalibration (derived from Deming regression) from each approach to the original measurements, the prevalence of hyperuricemia (>7 mg/dL) was 28.5% before IOR and 8.5% after IOR. IOR is a useful method for removal of extreme outliers irrelevant to recalibrating laboratory measurements, and identifies more extraneous outliers than the standard approach. © 2016 American Association for Clinical Chemistry.

  6. Modulation of gregarious settlement of the stalked barnacle, Pollicipes pollicipes: a laboratory study

    Directory of Open Access Journals (Sweden)

    Sofia C. Franco

    2016-06-01

    Full Text Available Although recruitment patterns of Pollicipes pollicipes (Crustacea: Scalpelliformes in the wild have been investigated, no studies have yet focused on the factors that affect settlement. In the present paper, settlement of P. pollicipes on conspecifics (gregarious settlement was investigated in the laboratory as a function of environmental conditions (hydrodynamics, temperature, light and salinity, larval age and batch. This study aimed to understand how these factors modulate settlement in the laboratory and elucidate how they might impact recruitment patterns in nature. Maximum attachment on adults was 30-35%, with a one-week metamorphosis rate of 70-80%. Batch differences affected both attachment and metamorphosis. Attachment rate was higher at natural salinity (30-40 psu, with lower salinity (20 psu decreasing metamorphosis rate. Cyprid attachment was stimulated by light conditions and circulating water. This might relate to a preference for positioning high in the water column in nature, but also to increased cyprid-surface contact in conditions of circulating water. Older cyprids (3 or 6 days showed higher attachment than un-aged larvae, though fewer 6-day-old larvae metamorphosed. Temperature did not affect attachment rate, but the metamorphosis rate decreased at 14°C (compared with 17 or 20°C, implying that differences in temperature during the breeding season can affect how quickly cyprids metamorphose to the juvenile. Cyprids survived for prolonged periods ( ≥ 20 days; 40% survival, likely due to efficient energy saving by intercalating long periods of inactivity with fast bursts of activity upon stimulation.

  7. Laboratory Study of Magnetic Reconnection in 3D Geometry Relevant to Magnetopause and Magnetotail

    Science.gov (United States)

    Ren, Y.; Lu, Q.; Ji, H.; Mao, A.; Wang, X.; E, P.; Wang, Z.; Xiao, Q.; Ding, W.; Zheng, J.

    2015-12-01

    Laboratory Study of Magnetic Reconnection in 3D Geometry Relevant to Magnetopause and Magnetotail Y. Ren1,2, Quaming Lu3, Hantao Ji1,2, Aohua Mao1, Xiaogang Wang1, Peng E1, Zhibin Wang1, Qingmei Xiao1, Weixing Ding4, Jinxing Zheng51 Harbin Institute of Technology, Harbin, China2 Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 3University of Science and Technology of China, Hefei, China 4University of California at Los Angeles, Los Angeles, CA, 90095 5ASIPP, Hefei, China A new magnetic reconnection experiment, Harbin reconnection eXperiment (HRX), is currently being designed as a key part of Space Plasma Environment Research Facility (SPERF) at Harbin Institute of Technology in Harbin, China. HRX aims to provide a unique experimental platform for studying reconnections in 3D geometry relevant to magnetopause and magnetotail to address: the role of electron and ion-scale dynamics in the current sheet; particle and energy transfer from magnetosheath to magnetosphere; particle energization/heating mechanisms during magnetic reconnection; 3D effects in fast reconnection, e.g. the role of 3D magnetic null point. HRX employs a unique set of coils to generate the required 3D magnetic geometry and provides a wide range of plasma parameters. Here, important motivating scientific problems are reviewed and the physics design of HRX is presented, including plasma parameters determined from Vlasov scaling law, reconnection scenarios explored using vacuum magnetic field calculations and numerical simulations of HRX using hybrid and MHD codes. Plasma diagnostics plan and engineering design of important coils will also be briefly presented.

  8. Sexual orientation differences in teen pregnancy and hormonal contraceptive use: An examination across two generations

    Science.gov (United States)

    Charlton, Brittany M.; Corliss, Heather L.; Missmer, Stacey A.; Rosario, Margaret; Spiegelman, Donna; Austin, S. Bryn

    2013-01-01

    Objectives To examine whether sexual orientation is associated with disparities in teen pregnancy and hormonal contraception use among adolescent females in two intergenerational cohorts. Study Design Data were collected from 91,003 women in the Nurses’ Health Study II (NHSII),born between 1947–1964, and 6,463 of their children, born between 1982–1987, enrolled in the Growing Up Today Study (GUTS). Log-binomial models were used to estimate risk ratios (RR) for teen pregnancy and hormonal contraception use in sexual minorities compared to heterosexuals and meta-analysis techniques were used to compare the two cohorts. Results Overall, teen hormonal contraception use was lower and teen pregnancy was higher in NHSII than GUTS. In both cohorts, lesbians were less likely, whereas the other sexual minorities were more likely, to use hormonal contraception as teenagers compared to their heterosexual peers. All sexual minority groups in both cohorts, except NHSII lesbians, were at significantly increased risk for teen pregnancy, with RRs ranging from 1.61 (95%CI 0.40, 6.55) to 5.82 (95%CI 2.89, 11.73). Having a NHSII mother who was pregnant as a teen was not associated with teen pregnancy in GUTS participants. Finally, significant heterogeneity was found between the two cohorts. Conclusions Adolescent sexual minorities have been, and continue to be, at increased risk for pregnancy. Public health and clinical efforts are needed to address teen pregnancy in this population. PMID:23796650

  9. Water Efficiency Improvements at Various Environmental Protection Agency Sites: Best Management Practice Case Study #12 - Laboratory/Medical Equipment (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    Blakley, H.

    2011-03-01

    The U.S. Environmental Protection Agency (EPA) built a successful water conservation program and reduced potable water use through a series of initiatives at EPA laboratories. The projects highlighted in this case study demonstrate EPA's ability to reduce water use in laboratory and medical equipment by implementing vacuum pump and steam sterilizer replacements and retrofits. Due to the success of the initial vacuum pump and steam sterilizer projects described here, EPA is implementing similar projects at several laboratories throughout the nation.

  10. Laboratory studies on surface sampling of Bacillus anthracis contamination: summary, gaps, and recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Piepel, Gregory F.; Amidan, Brett G.; Hu, Rebecca

    2012-12-01

    This article summarizes previous laboratory studies to characterize the performance of methods for collecting, storing/transporting, processing, and analyzing samples from surfaces contaminated by Bacillus anthracis or related surrogates. The focus is on plate culture and count estimates of surface contamination for swab, wipe, and vacuum samples of porous and nonporous surfaces. Summaries of the previous studies and their results were assessed to identify gaps in information needed as inputs to calculate key parameters critical to risk management in biothreat incidents. One key parameter is the number of samples needed to make characterization or clearance decisions with specified statistical confidence. Other key parameters include the ability to calculate, following contamination incidents, the 1) estimates of Bacillus anthracis contamination, as well as the bias and uncertainties in the estimates, and 2) confidence in characterization and clearance decisions for contaminated or decontaminated buildings. Gaps in knowledge and understanding identified during the summary of the studies are discussed. Recommendations are given for future evaluations of data from existing studies and possible new studies.

  11. A review of toxicity studies of single-walled carbon nanotubes in laboratory animals.

    Science.gov (United States)

    Ema, Makoto; Gamo, Masashi; Honda, Kazumasa

    2016-02-01

    We summarized the findings of in vivo toxicity studies of single-walled carbon nanotubes (SWCNTs) in laboratory animals. The large majority addressed the pulmonary toxicity of SWCNTs in rodents. Inhalation, pharyngeal aspiration, and intratracheal instillation studies revealed that SWCNTs caused acute and chronic inflammation, granuloma formation, collagen deposition, fibrosis, and genotoxic effects in the lungs. Pulmonary toxicity of well-dispersed SWCNTs was more potent than less dispersed ones. Airway exposure to SWCNTs also induced cardiovascular diseases in mice. Oxidative stress was caused by the administration of SWCNTs. Injected SWCNTs were distributed throughout most of the organs including the brain, mainly retained in the lungs, liver, and spleen, and eliminated through the kidney and bile duct. Orally administered SWCNTs are suggested to be absorbed from the gastrointestinal tract to the blood circulation in mice and rats. Although no definitive study on the carcinogenicity of SWCNTs is available at present, evidence of carcinogenicity has not been reported in toxicity studies cited in this review. Overall, the available data provides initial information on SWCNT toxicity. To further clarify their toxicity and risk assessment, studies should be conducted using well-characterized SWCNTs, standard protocols, and the relevant route and doses of human exposure.

  12. New liquid crystalline materials based on two generations of dendronised cyclophosphazenes.

    Science.gov (United States)

    Jiménez, Josefina; Laguna, Antonio; Gascón, Elena; Sanz, José Antonio; Serrano, José Luis; Barberá, Joaquín; Oriol, Luis

    2012-12-21

    A divergent approach was used for the synthesis of dendritic structures based on a cyclotriphosphazene core with 12 or 24 hydroxyl groups, by starting from [N(3)P(3)(OC(6)H(4)OH-4)(6)] and using an acetal-protected 2,2-di(hydroxymethyl)propionic anhydride as the acylating agent. Hydroxyl groups in these first- and second-generation dendrimers, G1-(OH)(12) or G2-(OH)(24), were then condensed in turn with mono- or polycatenar pro-mesogenic acids to study their ability to promote self-assembly into liquid crystalline structures. Reactions were monitored by using (31)P{(1)H} and (1)H NMR spectroscopy and the chemical structure of the resulting materials was confirmed by using different spectroscopic techniques and mass spectrometry (MALDI-TOF MS). The results were in accordance with monodisperse, fully functionalised cyclotriphosphazene dendrimers. Thermal and liquid crystalline properties were studied by using optical microscopy, differential scanning calorimetry and X-ray diffraction. The dendrimer with 12 4-pentylbiphenyl mesogenic units gives rise to columnar rectangular organisation, whereas the one with 24 pentylbiphenyl units does not exhibit mesomorphic behaviour. In the case of materials that contain polycatenar pro-mesogenic units with two aromatic rings (A4 vs. A5), the incorporation of a short flexible spacer connected to the periphery of the dendron (acid A5) was needed to achieve mesomorphic organisation. In this case, both dendrimer generations G1 A5 and G2 A5 exhibit a hexagonal columnar mesophase.

  13. Comprehensive study of proteasome inhibitors against Plasmodium falciparum laboratory strains and field isolates from Gabon

    Directory of Open Access Journals (Sweden)

    Kremsner Peter G

    2008-09-01

    Full Text Available Abstract Background The emergence and spread of Plasmodium falciparum resistance to almost all available antimalarial drugs necessitates the search for new chemotherapeutic compounds. The ubiquitin/proteasome system plays a major role in overall protein turnover, especially in fast dividing eukaryotic cells including plasmodia. Previous studies show that the 20S proteasome is expressed and catalytically active in plasmodia and treatment with proteasome inhibitors arrests parasite growth. This is the first comprehensive screening of proteasome inhibitors with different chemical modes of action against laboratory strains of P. falciparum. Subsequently, a selection of inhibitors was tested in field isolates from Lambaréné, Gabon. Methods Epoxomicin, YU101, YU102, MG132, MG115, Z-L3-VS, Ada-Ahx3-L3-VS, lactacystin, bortezomib (Velcade®, gliotoxin, PR11 and PR39 were tested and compared to chloroquine- and artesunate-activities in a standardized in vitro drug susceptibility assay against P. falciparum laboratory strains 3D7, D10 and Dd2. Freshly obtained field isolates from Lambaréné, Gabon, were used to measure the activity of chloroquine, artesunate, epoxomicin, MG132, lactacystin and bortezomib. Parasite growth was detected through histidine-rich protein 2 (HRP2 production. Raw data were fitted by a four-parameter logistic model and individual inhibitory concentrations (50%, 90%, and 99% were calculated. Results Amongst all proteasome inhibitors tested, epoxomicin showed the highest activity in chloroquine-susceptible (IC50: 6.8 nM [3D7], 1.7 nM [D10] and in chloroquine-resistant laboratory strains (IC50: 10.4 nM [Dd2] as well as in field isolates (IC50: 8.5 nM. The comparator drug artesunate was even more active (IC50: 1.0 nM, whereas all strains were chloroquine-resistant (IC50: 113 nM. Conclusion The peptide α',β'-epoxyketone epoxomicin is highly active against P. falciparum regardless the grade of the parasite's chloroquine

  14. Physician satisfaction with clinical laboratory services: a College of American Pathologists Q-probes study of 138 institutions.

    Science.gov (United States)

    Jones, Bruce A; Bekeris, Leonas G; Nakhleh, Raouf E; Walsh, Molly K; Valenstein, Paul N

    2009-01-01

    Monitoring customer satisfaction is a valuable component of a laboratory quality improvement program. To survey the level of physician satisfaction with hospital clinical laboratory services. Participating institutions provided demographic and practice information and survey results of physician satisfaction with defined aspects of clinical laboratory services, rated on a scale of 1 (poor) to 5 (excellent). One hundred thirty-eight institutions participated in this study and submitted a total of 4329 physician surveys. The overall satisfaction score for all institutions ranged from 2.9 to 5.0. The median overall score for all participants was 4.1 (10th percentile, 3.6; 90th percentile, 4.5). Physicians were most satisfied with the quality/reliability of results and staff courtesy, with median values of excellent or good ratings of 89.9%. Of the 5 service categories that received the lowest percentage values of excellent/good ratings (combined scores of 4 and 5), 4 were related to turnaround time for inpatient stat, outpatient stat, routine, and esoteric tests. Surveys from half of the participating laboratories reported that 96% to 100% of physicians would recommend the laboratory to other physicians. The category most frequently selected as the most important category of laboratory services was quality/reliability of results (31.7%). There continues to be a high level of physician satisfaction and loyalty with clinical laboratory services. Test turnaround times are persistent categories of dissatisfaction and present opportunities for improvement.

  15. A female sex offender with multiple paraphilias: a psychologic, physiologic (laboratory sexual arousal) and endocrine case study.

    Science.gov (United States)

    Cooper, A J; Swaminath, S; Baxter, D; Poulin, C

    1990-05-01

    A 20 year old female pedophile exhibiting multiple paraphilias and who had been both a victim of incest and an active participant, undertook extensive clinical, psychometric, endocrine and laboratory sexual arousal studies. Her psychiatric, psychometric and physiologic arousal profiles showed similarities to those of a sizable proportion of male child molesters, especially incestors. It is suggested that laboratory arousal tests (using the vaginal photoplethysmograph) may have a role in the assessment of some female sex offenders.

  16. A 10-year study of specimens submitted to oral pathology laboratory analysis: lesion occurrence and demographic features

    OpenAIRE

    Marina Mendez; Vinicius Coelho Carrard; Alex Nogueira Haas; Isabel da Silva Lauxen; João Jorge Diniz Barbachan; Pantelis Varvaki Rados; Manoel Sant'Ana Filho

    2012-01-01

    The purpose of the present paper was to describe the range of lesions histologically diagnosed in an oral pathology laboratory in southern Brazil. A retrospective study of 8,168 specimen analyses recorded between 1995 and 2004 was conducted. The records were retrieved from the Oral Pathology Laboratory, School of Dentistry, Federal University of Rio Grande do Sul, RS, Brazil. A total of 6,831 valid cases (83.63%) were examined. Of these, inflammatory lesions were the most common occurrences (...

  17. Performance of viruses and bacteriophages for fecal source determination in a multi-laboratory, comparative study.

    Science.gov (United States)

    Harwood, Valerie J; Boehm, Alexandria B; Sassoubre, Lauren M; Vijayavel, Kannappan; Stewart, Jill R; Fong, Theng-Theng; Caprais, Marie-Paule; Converse, Reagan R; Diston, David; Ebdon, James; Fuhrman, Jed A; Gourmelon, Michele; Gentry-Shields, Jennifer; Griffith, John F; Kashian, Donna R; Noble, Rachel T; Taylor, Huw; Wicki, Melanie

    2013-11-15

    An inter-laboratory study of the accuracy of microbial source tracking (MST) methods was conducted using challenge fecal and sewage samples that were spiked into artificial freshwater and provided as unknowns (blind test samples) to the laboratories. The results of the Source Identification Protocol Project (SIPP) are presented in a series of papers that cover 41 MST methods. This contribution details the results of the virus and bacteriophage methods targeting human fecal or sewage contamination. Human viruses used as source identifiers included adenoviruses (HAdV), enteroviruses (EV), norovirus Groups I and II (NoVI and NoVII), and polyomaviruses (HPyVs). Bacteriophages were also employed, including somatic coliphages and F-specific RNA bacteriophages (FRNAPH) as general indicators of fecal contamination. Bacteriophage methods targeting human fecal sources included genotyping of FRNAPH isolates and plaque formation on bacterial hosts Enterococcus faecium MB-55, Bacteroides HB-73 and Bacteroides GB-124. The use of small sample volumes (≤50 ml) resulted in relatively insensitive theoretical limits of detection (10-50 gene copies or plaques × 50 ml(-1)) which, coupled with low virus concentrations in samples, resulted in high false-negative rates, low sensitivity, and low negative predictive values. On the other hand, the specificity of the human virus methods was generally close to 100% and positive predictive values were ∼40-70% with the exception of NoVs, which were not detected. The bacteriophage methods were generally much less specific toward human sewage than virus methods, although FRNAPH II genotyping was relatively successful, with 18% sensitivity and 85% specificity. While the specificity of the human virus methods engenders great confidence in a positive result, better concentration methods and larger sample volumes must be utilized for greater accuracy of negative results, i.e. the prediction that a human contamination source is absent.

  18. Detection of Microbial Life in Glacial Samples - Laboratories Studies and Development for Field use

    Science.gov (United States)

    Barnett, M. J.; Cullen, D. C.; Telling, J.; Wadham, J. L.; Holt, J.; Sims, M.

    2007-12-01

    Adenosine triphosphate (ATP) is frequently used as a proxy for bulk microbial biomass in environmental sciences and, in the food and health industries. Despite successful ATP detection in a variety of ecosystems, very little data are available on ATP levels in the glacial system. In this study, protocols for ATP detection on glacial ice and sediment samples are investigated, in order to aid in the development of a single-use device for in-field life detection, and also to increase the available data on biomass estimates in the cryosphere. ATP detection in two glacial samples reveals concentrations indistinguishable from internal blanks. Therefore, the samples were centrifuged and their particulate loads were subjected to four different extraction processes. Applying these extraction methods resulted in higher ATP concentration than samples with no extraction process; the different techniques increase the ATP detected between 5 and 15 times (also relative to an internal standard). Concurrent with the laboratory based development of extraction protocols is the development of a single-use device for the detection of ATP at the sampling site, in icy environments. The device is microfluidic-based, using commercially available reagents for the detection of ATP by bioluminescence. In order to produce a robust measure of biomass, both laboratory and field based analyses need to be carried out. This work shows the potential of ATP detection in glacial samples and the early development of a device for in situ life detection. The quantification of ATP in microfluidic format is being developed as the preliminary target for an integrated life detection and characterisation device.

  19. Three cases of CLIPPERS: a serial clinical, laboratory and MRI follow-up study.

    Science.gov (United States)

    Kastrup, O; van de Nes, J; Gasser, T; Keyvani, K

    2011-12-01

    The aim of the study was to further determine the pathophysiology, clinical course, MRI-features and response to therapy of chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS), which has recently been proposed as a rare chronic inflammatory central nervous system disorder responsive to immunosuppressive therapy. Three patients with this rare entity underwent serial clinical and bimonthly MRI follow-up over a period of up to 16 months. Extensive laboratory work-up and brain biopsy were performed. Intravenous methylprednisolone or oral dexamethasone was administered as treatment, additionally cyclophosphamide in one patient. Clinically, diplopia, nystagmus, ataxia and facial paresthesia were the cardinal symptoms. Magnetic resonance imaging (MRI) disclosed patchy spot-like gadolinium enhancement in a "salt-and-pepper like appearance" in the pons, midbrain and cerebellum, in two cases with thalamic and in the other with spinal involvement. Brain biopsies demonstrated a predominantly angiocentric but also diffuse infiltration pattern by small mature lymphocytes. Treatment with steroids led to rapid clinical improvement and marked resolution of MRI lesions. As discontinuation of steroids led to clinical relapse, one patient was treated with a further course of steroids and the other with steroids and cyclophosphamide as immunosuppressive therapy. This led to stable remission with only mild clinical residue and normalization of MRI. Extensive laboratory and radiological work-up could not identify any other cause of the disease. Of note, in two cases a marked elevation of IgE in serum was found initially and throughout the course. CLIPPERS seems to be a distinct inflammatory central nervous system disorder. It shows characteristic MRI core features. Extrapontine involvement seems to be frequent. Histologically it is characterised by predominantly angiocentric infiltration by small mature lymphocytes. A pathogenetic

  20. Identifying innovation in laboratory studies of cultural evolution: rates of retention and measures of adaptation.

    Science.gov (United States)

    Caldwell, Christine A; Cornish, Hannah; Kandler, Anne

    2016-03-19

    In recent years, laboratory studies of cultural evolution have become increasingly prevalent as a means of identifying and understanding the effects of cultural transmission on the form and functionality of transmitted material. The datasets generated by these studies may provide insights into the conditions encouraging, or inhibiting, high rates of innovation, as well as the effect that this has on measures of adaptive cultural change. Here we review recent experimental studies of cultural evolution with a view to elucidating the role of innovation in generating observed trends. We first consider how tasks are presented to participants, and how the corresponding conceptualization of task success is likely to influence the degree of intent underlying any deviations from perfect reproduction. We then consider the measures of interest used by the researchers to track the changes that occur as a result of transmission, and how these are likely to be affected by differing rates of retention. We conclude that considering studies of cultural evolution from the perspective of innovation provides us with valuable insights that help to clarify important differences in research designs, which have implications for the likely effects of variation in retention rates on measures of cultural adaptation.

  1. Identifying innovation in laboratory studies of cultural evolution: rates of retention and measures of adaptation

    Science.gov (United States)

    Caldwell, Christine A.; Cornish, Hannah; Kandler, Anne

    2016-01-01

    In recent years, laboratory studies of cultural evolution have become increasingly prevalent as a means of identifying and understanding the effects of cultural transmission on the form and functionality of transmitted material. The datasets generated by these studies may provide insights into the conditions encouraging, or inhibiting, high rates of innovation, as well as the effect that this has on measures of adaptive cultural change. Here we review recent experimental studies of cultural evolution with a view to elucidating the role of innovation in generating observed trends. We first consider how tasks are presented to participants, and how the corresponding conceptualization of task success is likely to influence the degree of intent underlying any deviations from perfect reproduction. We then consider the measures of interest used by the researchers to track the changes that occur as a result of transmission, and how these are likely to be affected by differing rates of retention. We conclude that considering studies of cultural evolution from the perspective of innovation provides us with valuable insights that help to clarify important differences in research designs, which have implications for the likely effects of variation in retention rates on measures of cultural adaptation. PMID:26926283

  2. Parallel Application Performance on Two Generations of Intel Xeon HPC Platforms

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Christopher H.; Long, Hai; Sides, Scott; Vaidhynathan, Deepthi; Jones, Wesley

    2015-10-15

    Two next-generation node configurations hosting the Haswell microarchitecture were tested with a suite of microbenchmarks and application examples, and compared with a current Ivy Bridge production node on NREL" tm s Peregrine high-performance computing cluster. A primary conclusion from this study is that the additional cores are of little value to individual task performance--limitations to application parallelism, or resource contention among concurrently running but independent tasks, limits effective utilization of these added cores. Hyperthreading generally impacts throughput negatively, but can improve performance in the absence of detailed attention to runtime workflow configuration. The observations offer some guidance to procurement of future HPC systems at NREL. First, raw core count must be balanced with available resources, particularly memory bandwidth. Balance-of-system will determine value more than processor capability alone. Second, hyperthreading continues to be largely irrelevant to the workloads that are commonly seen, and were tested here, at NREL. Finally, perhaps the most impactful enhancement to productivity might occur through enabling multiple concurrent jobs per node. Given the right type and size of workload, more may be achieved by doing many slow things at once, than fast things in order.

  3. Laboratory study of nitrate photolysis in Antarctic snow. II. Isotopic effects and wavelength dependence.

    Science.gov (United States)

    Berhanu, Tesfaye A; Meusinger, Carl; Erbland, Joseph; Jost, Rémy; Bhattacharya, S K; Johnson, Matthew S; Savarino, Joël

    2014-06-28

    Atmospheric nitrate is preserved in Antarctic snow firn and ice. However, at low snow accumulation sites, post-depositional processes induced by sunlight obscure its interpretation. The goal of these studies (see also Paper I by Meusinger et al. ["Laboratory study of nitrate photolysis in Antarctic snow. I. Observed quantum yield, domain of photolysis, and secondary chemistry," J. Chem. Phys. 140, 244305 (2014)]) is to characterize nitrate photochemistry and improve the interpretation of the nitrate ice core record. Naturally occurring stable isotopes in nitrate ((15)N, (17)O, and (18)O) provide additional information concerning post-depositional processes. Here, we present results from studies of the wavelength-dependent isotope effects from photolysis of nitrate in a matrix of natural snow. Snow from Dome C, Antarctica was irradiated in selected wavelength regions using a Xe UV lamp and filters. The irradiated snow was sampled and analyzed for nitrate concentration and isotopic composition (δ(15)N, δ(18)O, and Δ(17)O). From these measurements an average photolytic isotopic fractionation of (15)ɛ = (-15 ± 1.2)‰ was found for broadband Xe lamp photolysis. These results are due in part to excitation of the intense absorption band of nitrate around 200 nm in addition to the weaker band centered at 305 nm followed by photodissociation. An experiment with a filter blocking wavelengths shorter than 320 nm, approximating the actinic flux spectrum at Dome C, yielded a photolytic isotopic fractionation of (15)ɛ = (-47.9 ± 6.8)‰, in good agreement with fractionations determined by previous studies for the East Antarctic Plateau which range from -40 to -74.3‰. We describe a new semi-empirical zero point energy shift model used to derive the absorption cross sections of (14)NO3 (-) and (15)NO3 (-) in snow at a chosen temperature. The nitrogen isotopic fractionations obtained by applying this model under the experimental temperature as well as considering the

  4. Laboratory study of nitrate photolysis in Antarctic snow. II. Isotopic effects and wavelength dependence

    Science.gov (United States)

    Berhanu, Tesfaye A.; Meusinger, Carl; Erbland, Joseph; Jost, Rémy; Bhattacharya, S. K.; Johnson, Matthew S.; Savarino, Joël

    2014-06-01

    Atmospheric nitrate is preserved in Antarctic snow firn and ice. However, at low snow accumulation sites, post-depositional processes induced by sunlight obscure its interpretation. The goal of these studies (see also Paper I by Meusinger et al. ["Laboratory study of nitrate photolysis in Antarctic snow. I. Observed quantum yield, domain of photolysis, and secondary chemistry," J. Chem. Phys. 140, 244305 (2014)]) is to characterize nitrate photochemistry and improve the interpretation of the nitrate ice core record. Naturally occurring stable isotopes in nitrate (15N, 17O, and 18O) provide additional information concerning post-depositional processes. Here, we present results from studies of the wavelength-dependent isotope effects from photolysis of nitrate in a matrix of natural snow. Snow from Dome C, Antarctica was irradiated in selected wavelength regions using a Xe UV lamp and filters. The irradiated snow was sampled and analyzed for nitrate concentration and isotopic composition (δ15N, δ18O, and Δ17O). From these measurements an average photolytic isotopic fractionation of 15ɛ = (-15 ± 1.2)‰ was found for broadband Xe lamp photolysis. These results are due in part to excitation of the intense absorption band of nitrate around 200 nm in addition to the weaker band centered at 305 nm followed by photodissociation. An experiment with a filter blocking wavelengths shorter than 320 nm, approximating the actinic flux spectrum at Dome C, yielded a photolytic isotopic fractionation of 15ɛ = (-47.9 ± 6.8)‰, in good agreement with fractionations determined by previous studies for the East Antarctic Plateau which range from -40 to -74.3‰. We describe a new semi-empirical zero point energy shift model used to derive the absorption cross sections of 14NO3- and 15NO3- in snow at a chosen temperature. The nitrogen isotopic fractionations obtained by applying this model under the experimental temperature as well as considering the shift in width and center well

  5. Laboratory study of nitrate photolysis in Antarctic snow. II. Isotopic effects and wavelength dependence

    Energy Technology Data Exchange (ETDEWEB)

    Berhanu, Tesfaye A.; Erbland, Joseph; Savarino, Joël [Laboratoire de Glaciologie et Géophysique de l’Environnement, CNRS, F-38041 Grenoble (France); Univ. Grenoble Alpes, LGGE, F-38041 Grenoble (France); Meusinger, Carl; Johnson, Matthew S. [Copenhagen Center for Atmospheric Research (CCAR), Department of Chemistry, University of Copenhagen, Copenhagen (Denmark); Jost, Rémy [Laboratoire de Interdisciplinaire de Physique (LIPHY) Univ. de Grenoble, Grenoble (France); Bhattacharya, S. K. [Research Center for Environmental Changes, Academia Sinica, Nangang, Taipei 115, Taiwan (China)

    2014-06-28

    Atmospheric nitrate is preserved in Antarctic snow firn and ice. However, at low snow accumulation sites, post-depositional processes induced by sunlight obscure its interpretation. The goal of these studies (see also Paper I by Meusinger et al. [“Laboratory study of nitrate photolysis in Antarctic snow. I. Observed quantum yield, domain of photolysis, and secondary chemistry,” J. Chem. Phys. 140, 244305 (2014)]) is to characterize nitrate photochemistry and improve the interpretation of the nitrate ice core record. Naturally occurring stable isotopes in nitrate ({sup 15}N, {sup 17}O, and {sup 18}O) provide additional information concerning post-depositional processes. Here, we present results from studies of the wavelength-dependent isotope effects from photolysis of nitrate in a matrix of natural snow. Snow from Dome C, Antarctica was irradiated in selected wavelength regions using a Xe UV lamp and filters. The irradiated snow was sampled and analyzed for nitrate concentration and isotopic composition (δ{sup 15}N, δ{sup 18}O, and Δ{sup 17}O). From these measurements an average photolytic isotopic fractionation of {sup 15}ε = (−15 ± 1.2)‰ was found for broadband Xe lamp photolysis. These results are due in part to excitation of the intense absorption band of nitrate around 200 nm in addition to the weaker band centered at 305 nm followed by photodissociation. An experiment with a filter blocking wavelengths shorter than 320 nm, approximating the actinic flux spectrum at Dome C, yielded a photolytic isotopic fractionation of {sup 15}ε = (−47.9 ± 6.8)‰, in good agreement with fractionations determined by previous studies for the East Antarctic Plateau which range from −40 to −74.3‰. We describe a new semi-empirical zero point energy shift model used to derive the absorption cross sections of {sup 14}NO{sub 3}{sup −} and {sup 15}NO{sub 3}{sup −} in snow at a chosen temperature. The nitrogen isotopic fractionations obtained by applying

  6. Parentage versus two-generation analyses for estimating pollen-mediated gene flow in plant populations.

    Science.gov (United States)

    Burczyk, Jaroslaw; Koralewski, Tomasz E

    2005-07-01

    Assessment of contemporary pollen-mediated gene flow in plants is important for various aspects of plant population biology, genetic conservation and breeding. Here, through simulations we compare the two alternative approaches for measuring pollen-mediated gene flow: (i) the NEIGHBORHOOD model--a representative of parentage analyses, and (ii) the recently developed TWOGENER analysis of pollen pool structure. We investigate their properties in estimating the effective number of pollen parents (N(ep)) and the mean pollen dispersal distance (delta). We demonstrate that both methods provide very congruent estimates of N(ep) and delta, when the methods' assumptions considering the shape of pollen dispersal curve and the mating system follow those used in data simulations, although the NEIGHBORHOOD model exhibits generally lower variances of the estimates. The violations of the assumptions, especially increased selfing or long-distance pollen dispersal, affect the two methods to a different degree; however, they are still capable to provide comparable estimates of N(ep). The NEIGHBORHOOD model inherently allows to estimate both self-fertilization and outcrossing due to the long-distance pollen dispersal; however, the TWOGENER method is particularly sensitive to inflated selfing levels, which in turn may confound and suppress the effects of distant pollen movement. As a solution we demonstrate that in case of TWOGENER it is possible to extract the fraction of intraclass correlation that results from outcrossing only, which seems to be very relevant for measuring pollen-mediated gene flow. The two approaches differ in estimation precision and experimental efforts but they seem to be complementary depending on the main research focus and type of a population studied.

  7. Ingestion of radioactively contaminated diets for two generations in the pale grass blue butterfly.

    Science.gov (United States)

    Nohara, Chiyo; Taira, Wataru; Hiyama, Atsuki; Tanahara, Akira; Takatsuji, Toshihiro; Otaki, Joji M

    2014-09-23

    The release of radioactive materials due to the Fukushima nuclear accident has raised concern regarding the biological impacts of ingesting radioactively contaminated diets on organisms. We previously performed an internal exposure experiment in which contaminated leaves collected from polluted areas were fed to larvae of the pale grass blue butterfly, Zizeeria maha, from Okinawa, which is one of the least polluted localities in Japan. Using the same experimental system, in the present study, we further examined the effects of low-level-contaminated diets on this butterfly. Leaves were collected from two localities in Tohoku (Motomiya (161 Bq/kg) and Koriyama (117 Bq/kg)); two in Kanto (Kashiwa (47.6 Bq/kg) and Musashino (6.4 Bq/kg)); one in Tokai (Atami (2.5 Bq/kg)); and from Okinawa (0.2 Bq/kg). In addition to the effects on the first generation, we examined the possible transgenerational effects of the diets on the next generation. In the first generation, the Tohoku groups showed higher rates of mortality and abnormalities and a smaller forewing size than the Okinawa group. The mortality rates were largely dependent on the ingested dose of caesium. The survival rates of the Kanto-Tokai groups were greater than 80%, but the rates in the Tohoku groups were much lower. In the next generation, the survival rates in the Tohoku groups were below 20%, whereas those of the Okinawa groups were above 70%. The survival rates in the second generation were independent of the locality of the leaves ingested by the first generation, indicating that the diet in the second generation was the determinant of their survival. Moreover, a smaller forewing size was observed in the Tohoku groups in the second generation. However, the forewing size was inversely correlated with the cumulative caesium dose ingested throughout the first and second generations, indicating that the diet in the first generation also influenced the forewing size of the second generation. Biological

  8. Advancing internal erosion monitoring using seismic methods in field and laboratory studies

    Science.gov (United States)

    Parekh, Minal L.

    This dissertation presents research involving laboratory and field investigation of passive and active methods for monitoring and assessing earthen embankment infrastructure such as dams and levees. Internal erosion occurs as soil particles in an earthen structure migrate to an exit point under seepage forces. This process is a primary failure mode for dams and levees. Current dam and levee monitoring practices are not able to identify early stages of internal erosion, and often the result is loss of structure utility and costly repairs. This research contributes to innovations for detection and monitoring by studying internal erosion and monitoring through field experiments, laboratory experiments, and social and political framing. The field research in this dissertation included two studies (2009 and 2012) of a full-scale earthen embankment at the IJkdijk in the Netherlands. In both of these tests, internal erosion occurred as evidenced by seepage followed by sand traces and boils, and in 2009, eventual failure. With the benefit of arrays of closely spaced piezometers, pore pressure trends indicated internal erosion near the initiation time. Temporally and spatially dense pore water pressure measurements detected two pore water pressure transitions characteristic to the development of internal erosion, even in piezometers located away from the backward erosion activity. At the first transition, the backward erosion caused anomalous pressure decrease in piezometers, even under constant or increasing upstream water level. At the second transition, measurements stabilized as backward erosion extended further upstream of the piezometers, as shown in the 2009 test. The transitions provide an indication of the temporal development and the spatial extent of backward erosion. The 2012 IJkdijk test also included passive acoustic emissions (AE) monitoring. This study analyzed AE activity over the course of the 7-day test using a grid of geophones installed on the

  9. Final Report for the Arroyo Las Positas Maintenance Impact Study, Lawrence Livermore National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    van Hattem, M; Paterson, L

    2006-01-12

    In 2000, the Lawrence Livermore National Laboratory's (LLNL) Environmental Protection Department, in coordination with Plant Engineering (PE), began dredging sections of the Arroyo Las Positas (ALP) to alleviate concerns about flooding of sensitive facilities within the mainsite of Lawrence Livermore National Laboratory. In order to reduce potential impacts on the federally threatened California red-legged frog (Rana aurora draytonii), LLNL proposed to dredge sections of the ALP in a ''checkerboard pattern'', resulting in a mosaic of open water habitat and vegetated sections (Figure 1). The Arroyo Las Positas Management Plan (Plan) was coordinated with both state and federal agencies including the U.S. Fish and Wildlife Service (USFWS), California Department of Fish and Game (CDF&G), San Francisco Regional Water Quality Control Board (SFRWQCB), and the Army Corp of Engineers (ACOE). Water Discharge Requirements (WDRs) were issued for this project on December 30, 1999 (Order No. 99-086) by the SFRWQCB. Provision 19 of the WDRs outlined a five-year (2000 through 2004) Maintenance Impact Study (MIS) that LLNL began in coordination with dredging work that was conducted as part of the Arroyo Las Positas Management Plan. Provision 20 of these WDRs requires LLNL to submit a final report of the results of the Maintenance Impact Study for this project to the SFRWQCB. The purpose of this report is to present the results of the Maintenance Impact Study for Arroyo Las Positas and meet the requirements of Provision 20. A description of the annual monitoring included in this Maintenance Impact Study is included in the methods section of this report. Initially the Plan called for dredging the entire length of the Arroyo Las Positas (approximately 6,981 linear feet) over a 5-year period to minimize temporal impacts on the California red-legged frog. Dredging occurred in 2000 ({approx}1,300 ft.), 2001 ({approx}800 ft.), and 2002 ({approx}1,200 ft.), which

  10. Design, development, testing and validation of a Photonics Virtual Laboratory for the study of LEDs

    Science.gov (United States)

    Naranjo, Francisco L.; Martínez, Guadalupe; Pérez, Ángel L.; Pardo, Pedro J.

    2014-07-01

    This work presents the design, development, testing and validation of a Photonic Virtual Laboratory, highlighting the study of LEDs. The study was conducted from a conceptual, experimental and didactic standpoint, using e-learning and m-learning platforms. Specifically, teaching tools that help ensure that our students perform significant learning have been developed. It has been brought together the scientific aspect, such as the study of LEDs, with techniques of generation and transfer of knowledge through the selection, hierarchization and structuring of information using concept maps. For the validation of the didactic materials developed, it has been used procedures with various assessment tools for the collection and processing of data, applied in the context of an experimental design. Additionally, it was performed a statistical analysis to determine the validity of the materials developed. The assessment has been designed to validate the contributions of the new materials developed over the traditional method of teaching, and to quantify the learning achieved by students, in order to draw conclusions that serve as a reference for its application in the teaching and learning processes, and comprehensively validate the work carried out.

  11. Sky compass orientation in desert locusts – evidence from field and laboratory studies

    Directory of Open Access Journals (Sweden)

    Uwe eHomberg

    2015-12-01

    Full Text Available Locusts are long-range migratory insects. At high population density, immature animals form marching hopper bands while adults take off and form huge swarms of millions of animals. At low population densities animals are solitarious, but likewise migrate, mostly during the night. Numerous studies aimed at predicting locust infestations showed that migrations both as hopper bands and as adults are largely downwind following seasonal shifts of the tropical convergence zone taking the animals to areas of rainfall. Only a few studies provided evidence for active orientation mechanisms, including the involvement of a sun compass. This scarcity of evidence stands in contrast to recent neurobiological data showing sophisticated neuronal adaptations suited for sky compass navigation. These include a special dorsal eye region with photoreceptors suited to analyze the polarization pattern of the sky and a system of topographically arranged sky compass neurons in the central complex of the brain. Laboratory experiments, moreover, demonstrated polarotaxis in tethered flying animals. The discrepancy of these findings call for more rigorous field studies on active orientation mechanisms in locusts. It remains to be shown how locusts use their internal sky compass during mass migrations and what role it plays to guide solitarious locusts in their natural habitat.

  12. [Value of the microarray for the study of Laboratory Animal Allergy (LAA)].

    Science.gov (United States)

    D'Ovidio, Maria Concetta; Martini, Agnese; Melis, Paola; Signorini, Stefano

    2011-01-01

    Since 1989, the National Institute for Occupational Safety and Health (NIOSH) considers the Laboratory Animal Allergy - LAA a risk for workers and in 1998 the LAA has been recognized as occupational risk in the USA. Rat and mouse are the most source of allergens, not so much for the higher power of allergy respect to the other animals, but because represent the more utilized species in the research. Most of the allergens are members of the lipocalin superfamily, small extracellular proteins represented by at least 50 proteins that mainly bind or carry small hydrophobic molecules. The recent and innovative molecular techniques, as the microarray, have allow the characterization of numerous allergens. The protein microarray gives the possibility to study of IgE profile for each individual, simultaneos analysis of a wide number of parameters concerning the allergy, giving new diagnostic and therapeutic opportunities for the allergies. In the study of occupational allergy--as LAA--the protein microarray could improve: the identification and characterization of new allergens; the individuation of susceptible workers; the study of immunological responses in exposed workers; the strategies of prevention and protection; the environmental and housing conditions. The participation, formation and information of the workers could improve the behavioural and occupational practices, the use of personal and collective protective devices in order to reduce the exposure to LAA in occupational context.

  13. Laboratory studies on the effects of shear on fish: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Neitzel, Duane A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Richmond, M. C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dauble, D. D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mueller, R. P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Moursund, R. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Abernethy, C. S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Guensch, G. R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cada, G. F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2000-09-01

    The overall objective of these studies was to specify an index describing the hydraulic force that fish experience when subjected to a shear environment. Fluid shear is a phenomenon that is important to fish. However, elevated levels of shear may result in strain rates that injure or kill fish. At hydroelectric generating facilities, concerns have been expressed that strain rates associated with passage through turbines, spillways, and fish bypass systems may adversely affect migrating fish. Development of fish-friendly hydroelectric turbines requires knowledge of the physical forces (injury mechanisms) that impact entrained fish and the fish’s tolerance to these forces. It requires up-front, pre-design specifications for the environmental conditions that occur within the turbine system; in other words, determining or assuming conditions known to injure fish will assist engineers in the design of a fish-friendly turbine system. To address the development of biological specifications, this experiment designed and built a test facility where juvenile fish could be subjected to a range of shear environments and quantified their biological response. The test data reported here provide quantified strain rates and the relationship of these forces to direct and indirect biological effects on fish. The study concludes that juvenile salmonids and American shad should survive shear environments where strain rates do not exceed 500 cm/s/cm at a Dy of 1.8 cm. Additional studies are planned with a sensor fish to better link hydraulic conditions found within the laboratory and field environments.

  14. The Adriatic Sea: A Long-Standing Laboratory for Sea Level Studies

    Science.gov (United States)

    Vilibić, Ivica; Šepić, Jadranka; Pasarić, Mira; Orlić, Mirko

    2017-07-01

    The paper provides a comprehensive review of all aspects of Adriatic Sea level research covered by the literature. It discusses changes occurring over millennial timescales and documented by a variety of natural and man-made proxies and post-glacial rebound models; mean sea level changes occurring over centennial to annual timescales and measured by modern instruments; and daily and higher-frequency changes (with periods ranging from minutes to a day) that are contributing to sea level extremes and are relevant for present-day flooding of coastal areas. Special tribute is paid to the historic sea level studies that shaped modern sea level research in the Adriatic, followed by a discussion of existing in situ and remote sensing observing systems operating in the Adriatic area, operational forecasting systems for Adriatic storm surges, as well as warning systems for tsunamis and meteotsunamis. Projections and predictions of sea level and related hazards are also included in the review. Based on this review, open issues and research gaps in the Adriatic Sea level studies are identified, as well as the additional research efforts needed to fill the gaps. The Adriatic Sea, thus, remains a laboratory for coastal sea level studies for semi-enclosed, coastal and marginal seas in the world ocean.

  15. A borehole stability study by newly designed laboratory tests on thick-walled hollow cylinders

    Directory of Open Access Journals (Sweden)

    S.S. Hashemi

    2015-10-01

    Full Text Available At several mineral exploration drilling sites in Australia, weakly consolidated formations mainly consist of sand particles that are poorly bonded by cementing agents such as clay, iron oxide cement or calcite. These formations are being encountered when drilling boreholes to the depth of up to 200 m. To study the behaviour of these materials, thick-walled hollow cylinder (TWHC and solid cylindrical synthetic specimens were designed and prepared by adding Portland cement and water to sand grains. The effects of different parameters such as water and cement contents, grain size distribution and mixture curing time on the characteristics of the samples were studied to identify the mixture closely resembling the formation at the drilling site. The Hoek triaxial cell was modified to allow the visual monitoring of grain debonding and borehole breakout processes during the laboratory tests. The results showed the significance of real-time visual monitoring in determining the initiation of the borehole breakout. The size-scale effect study on TWHC specimens revealed that with the increasing borehole size, the ductility of the specimen decreases, however, the axial and lateral stiffnesses of the TWHC specimen remain unchanged. Under different confining pressures the lateral strain at the initiation point of borehole breakout is considerably lower in a larger size borehole (20 mm compared to that in a smaller one (10 mm. Also, it was observed that the level of peak strength increment in TWHC specimens decreases with the increasing confining pressure.

  16. ELF electric and magnetic fields: Pacific Northwest Laboratory studies. [Extremely Low Frequency (ELF)

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, L.E.

    1992-06-01

    Studies have been conducted at Battelle, Pacific Northwest Laboratory, to examine extremely-low-frequency (ELF) electromagnetic fields for possible biological effects in animals. Three areas of investigation are reported here: (1) studies on the nervous system, including behavior and neuroendocrine function, (2) experiments on cancer development in animals, and (3) measurements of currents and electric fields induced in animal models by exposure to external magnetic fields. In behavioral experiments, rats have been shown to be responsive to ELF electric field exposure. Furthermore, experimental data indicate that short-term memory may be affected in albino rats exposed to combined ELF and static magnetic fields. Neuroendocrine studies have been conducted to demonstrate an apparent stress-related response in rats exposed to 60-Hz electric fields. Nighttime pineal melatonin levels have been shown to be significantly depressed in animals exposed to either electric or magnetic fields. A number of animal tumor models are currently under investigation to examine possible relationships between ELF exposure and carcinogenesis. Finally, theoretical and experimental measurements have been performed which form the basis for animals and human exposure comparisons.

  17. Sky Compass Orientation in Desert Locusts-Evidence from Field and Laboratory Studies.

    Science.gov (United States)

    Homberg, Uwe

    2015-01-01

    Locusts are long-range migratory insects. At high population density, immature animals form marching hopper bands while adults take off and form huge swarms of millions of animals. At low population densities animals are solitarious, but likewise migrate, mostly during the night. Numerous studies aimed at predicting locust infestations showed that migrations both as hopper bands and as adults are largely downwind following seasonal shifts of the tropical convergence zone taking the animals to areas of rainfall. Only a few studies provided evidence for active orientation mechanisms, including the involvement of a sun compass. This scarcity of evidence stands in contrast to recent neurobiological data showing sophisticated neuronal adaptations suited for sky compass navigation. These include a special dorsal eye region with photoreceptors suited to analyze the polarization pattern of the sky and a system of topographically arranged sky compass neurons in the central complex of the brain. Laboratory experiments, moreover, demonstrated polarotaxis in tethered flying animals. The discrepancy of these findings call for more rigorous field studies on active orientation mechanisms in locusts. It remains to be shown how locusts use their internal sky compass during mass migrations and what role it plays to guide solitarious locusts in their natural habitat.

  18. Study of the comprehension of the scientific method by members of a university health research laboratory.

    Science.gov (United States)

    Burlamaque-Neto, A C; Santos, G R; Lisbôa, L M; Goldim, J R; Machado, C L B; Matte, U; Giugliani, R

    2012-02-01

    In Brazil, scientific research is carried out mainly at universities, where professors coordinate research projects with the active participation of undergraduate and graduate students. However, there is no formal program for the teaching/learning of the scientific method. The objective of the present study was to evaluate the comprehension of the scientific method by students of health sciences who participate in scientific projects in an academic research laboratory. An observational descriptive cross-sectional study was conducted using Edgar Morin complexity as theoretical reference. In a semi-structured interview, students were asked to solve an abstract logical puzzle - TanGram. The collected data were analyzed using the hermeneutic-dialectic analysis method proposed by Minayo and discussed in terms of the theoretical reference of complexity. The students' concept of the scientific method is limited to participation in projects, stressing the execution of practical procedures as opposed to scientific thinking. The solving of the TanGram puzzle revealed that the students had difficulties in understanding questions and activities focused on subjects and their processes. Objective answers, even when dealing with personal issues, were also reflected on the students' opinions about the characteristics of a successful researcher. Students' difficulties concerning these issues may affect their scientific performance and result in poorly designed experiments. This is a preliminary study that should be extended to other centers of scientific research.

  19. The cleanroom case study in the Software Engineering Laboratory: Project description and early analysis

    Science.gov (United States)

    Green, Scott; Kouchakdjian, Ara; Basili, Victor; Weidow, David

    1990-01-01

    This case study analyzes the application of the cleanroom software development methodology to the development of production software at the NASA/Goddard Space Flight Center. The cleanroom methodology emphasizes human discipline in program verification to produce reliable software products that are right the first time. Preliminary analysis of the cleanroom case study shows that the method can be applied successfully in the FDD environment and may increase staff productivity and product quality. Compared to typical Software Engineering Laboratory (SEL) activities, there is evidence of lower failure rates, a more complete and consistent set of inline code documentation, a different distribution of phase effort activity, and a different growth profile in terms of lines of code developed. The major goals of the study were to: (1) assess the process used in the SEL cleanroom model with respect to team structure, team activities, and effort distribution; (2) analyze the products of the SEL cleanroom model and determine the impact on measures of interest, including reliability, productivity, overall life-cycle cost, and software quality; and (3) analyze the residual products in the application of the SEL cleanroom model, such as fault distribution, error characteristics, system growth, and computer usage.

  20. Measurements @ Sub-Mm Spectroscopy Laboratory of Bologna: Rotational Spectroscopy Applied to Atmospheric Studies

    Science.gov (United States)

    Puzzarini, Cristina

    2016-06-01

    The physico-chemistry of the Earth's atmosphere has been one of the main subjects of studies over last years. In particular, the composition of the atmosphere is indeed very important to understand chemical processes linked to depletion of stratospheric ozone and greenhouse effect. The vertical concentration profiles of atmospheric gases can be provided by remote sensing measurements, but they require the accurate knowledge of the parameters involved: line positions, transition intensities, pressure-broadened half-widths, pressure-induced frequency shifts and their temperature dependence. In particular, the collisional broadening parameters have a crucial influence on the accuracy of spectra calculations and on reduction of remote sensing data. Rotational spectroscopy, thanks to its intrinsic high resolution, is a powerful tool for providing most of the information mentioned above: accurate or even very accurate rotational transition frequencies, accurate spectroscopic as well as hyperfine parameters, accurate pressure-broadening coefficients and their temperature dependence. With respect to collisional phenomena and line shape analysis studies, by applying the source frequency modulation technique it has been found that rotational spectroscopy may provide very good results: not only this technique does not produce uncontrollable instrumental distortions or broadenings, but also, having an high sensitivity, it is particularly suitable for this kind of investigations. A number of examples will be presented to illustrate the work carried out at the Laboratory of Millimeter/submillimeter-wave Spectroscopy of Bologna in the field of atmospheric studies.

  1. Study of the comprehension of the scientific method by members of a university health research laboratory

    Directory of Open Access Journals (Sweden)

    A.C. Burlamaque-Neto

    2012-02-01

    Full Text Available In Brazil, scientific research is carried out mainly at universities, where professors coordinate research projects with the active participation of undergraduate and graduate students. However, there is no formal program for the teaching/learning of the scientific method. The objective of the present study was to evaluate the comprehension of the scientific method by students of health sciences who participate in scientific projects in an academic research laboratory. An observational descriptive cross-sectional study was conducted using Edgar Morin complexity as theoretical reference. In a semi-structured interview, students were asked to solve an abstract logical puzzle - TanGram. The collected data were analyzed using the hermeneutic-dialectic analysis method proposed by Minayo and discussed in terms of the theoretical reference of complexity. The students’ concept of the scientific method is limited to participation in projects, stressing the execution of practical procedures as opposed to scientific thinking. The solving of the TanGram puzzle revealed that the students had difficulties in understanding questions and activities focused on subjects and their processes. Objective answers, even when dealing with personal issues, were also reflected on the students’ opinions about the characteristics of a successful researcher. Students’ difficulties concerning these issues may affect their scientific performance and result in poorly designed experiments. This is a preliminary study that should be extended to other centers of scientific research.

  2. Evaluation of Linear Alkylbenzene Sulfonate (LAS) behaviour in agricultural soil through laboratory continuous studies.

    Science.gov (United States)

    Oliver-Rodríguez, B; Zafra-Gómez, A; Reis, M S; Duarte, B P M; Verge, C; de Ferrer, J A; Pérez-Pascual, M; Vílchez, J L

    2015-07-01

    The behaviour of Linear Alkylbenzene Sulfonate (LAS) in agricultural soil is investigated in the laboratory using continuous-flow soil column studies in order to simultaneously analyze the three main underlying phenomena (adsorption/desorption, degradation and transport). The continuous-flow soil column experiments generated the breakthrough curves for each LAS homologue, C10, C11, C12 and C13, and by adding them up, for total LAS, from which the relevant retention, degradation and transport parameters could be estimated, after proposing adequate models. Several transport equations were considered, including the degradation of the sorbate in solution and its retention by soil, under equilibrium and non-equilibrium conditions between the sorbent and the sorbate. In general, the results obtained for the estimates of those parameters that were common to the various models studied (such as the isotherm slope, first order degradation rate coefficient and the hydrodynamic dispersion coefficient) were rather consistent, meaning that mass transfer limitations are not playing a major role in the experiments. These three parameters increase with the length of the LAS homologue chain. The study will provide the underlying conceptual framework and fundamental parameters to understand, simulate and predict the environmental behaviour of LAS compounds in agricultural soils.

  3. Is there a First Night Effect on Sleep Bruxism? A Sleep Laboratory Study

    Science.gov (United States)

    Hasegawa, Yoko; Lavigne, Gilles; Rompré, Pierre; Kato, Takafumi; Urade, Masahiro; Huynh, Nelly

    2013-01-01

    Study Objectives: Sleep bruxism (SB) is reported to vary in frequency over time. The aim of this study was to assess the first night effect on SB. Methods: A retrospective polysomnographic (PSG) analysis was performed of data from a sample of SB patients (12 females, 4 males; age range: 17-39 years) recorded in a sleep laboratory over 2 consecutive nights. Sleep parameters and jaw muscle activity variables (i.e., rhythmic masticatory muscle activity [RMMA]) for SB were quantified and compared between the 2 nights. Subjects were classified into groups according to severity of RMMA frequency, such as low frequency (2-4 episodes/h and/or < 25 bursts/h) and moderate-high frequency (≥ 4 episodes/h and ≥ 25 bursts/h). Results: Overall, no first night effects were found for most sleep variables. However, total sleep time, sleep efficiency, and stage transitions showed significant time and group interactions (repeated measures ANOVAs, p ≤ 0.05). The RMMA episode index did not differ between the 2 nights, whereas the second night showed significantly higher burst index, bruxism time index, and mean burst duration (repeated measure ANOVAs, p ≤ 0.05). Five patients of 8 in the low frequency group were classified into the moderate-high frequency group on the second night, whereas only one patient in the moderate-high frequency group moved to the low frequency group. Conclusions: The results showed no overall first night effect on severity of RMMA frequency in young and healthy patients with SB. In clinical practice, one-night sleep recording may be sufficient for moderate-high frequency SB patients. However, low RMMA frequency in the first night could be confirmed by a second night based on the patient's medical and dental history. Citation: Hasegawa Y; Lavigne G; Rompré P; Kato T; Urade M; Huynh N. Is there a first night effect on sleep bruxism? A sleep laboratory study. J Clin Sleep Med 2013;9(11):1139-1145. PMID:24235894

  4. Laboratory Studies of FeO and NiO Chemiluminescence

    Science.gov (United States)

    Kalogerakis, K. S.; Bartlett, N. C.; Copeland, R. A.; Slanger, T. G.

    2013-12-01

    Although the terrestrial nightglow spectrum has been studied for over a century, new identifications of spectral features continue to be made. Recently, FeO* continuum emissions in the mesosphere were identified by comparison of results from the OSIRIS spectrometer to existing laboratory spectra [1]. This discovery has sparked a renewal of interest in the reactions of meteoric metals with mesospheric gases [2,3], and has motivated the current study. We report laboratory-based chemiluminescence spectra from the reactions Fe + O3 and Ni + O3 produced under various conditions. Iron and nickel vapor was prepared in a vacuum cell using laser ablation at 248 and 800 nm in the presence of ozone. Emission spectra from FeO* and NiO* were recorded in the region of 450-700 nm using a commercial fiber-coupled spectrometer and compared to previous results using different methods. Knowledge of the excited-state production efficiency of Fe + O3 → FeO* + O2 and the analogous reaction with Ni is critical in modeling upper atmospheric dynamics of meteoric metal layers. The only relevant experimental study in the literature for iron oxide is from West and Broida [4], who reported a yield of approximately 2% at around 1 Torr, in stark contrast with the 100% efficiency used in relevant model calculations [5]. This work was supported by the National Science Foundation's Aeronomy Program under grant AGS-0637433. References 1. W.F.J. Evans, R.L. Gattinger, T.G. Slanger, D.V. Saran, D.A. Degenstein, and E.J. Llewellyn, Geophys. Res. Lett., 37, L22105 (2010). 2. D.V. Saran, T.G. Slanger, W. Feng, and J.M.C. Plane, J. Geophys. Res. 116, D12303 (2011). 3. R.L. Gattinger, W.F.J. Evans, and E.J. Llewellyn, Canadian Journal of Physics 89, 869 (2011). 4. J.B. West and H.P. Broida, J. Chem. Phys. 62, 2566 (1975 ). 5. C.S. Gardner, J.M.C. Plane, W.L. Pan, T. Vondrak, B.J. Murray, and X.Z. Chu, J. Geophys. Res. 110, D10302 (2005).

  5. The Role of Laboratory Supervision in Improving the Quality of Malaria Diagnosis: A Pilot Study in Huambo, Angola.

    Science.gov (United States)

    Luckett, Rebecca; Mugizi, Rukaaka; Lopes, Sergio; Etossi, R Cacilda; Allan, Richard

    2016-03-01

    In 2006, the Angolan National Malaria Control Program introduced clinical guidelines for malaria case management, which included diagnostic confirmation of malaria before administration of treatment; however, diagnostic practices were inconsistent and of unknown quality. In 2009, a laboratory supervision program was implemented in Huambo Province, with the goal of assessing and improving diagnosis of malaria within the confines of available in-country resources. Supervisions were carried out from 2009 to 2014 using a standardized supervision tool by national laboratory trainers. Data from the first supervision were compared with that from the final supervision. Over the study period, the number and level of training of laboratory technicians increased, and there was a nonstatistically significant trend toward improved laboratory conditions. There was a significant reduction in false-positive microscopy slide reading (P = 0.0133). Laboratory infrastructural capacity to diagnose other communicable diseases, including syphilis, human immunodeficiency virus and hepatitis B virus infections (P = 0.0012, 0.0233 and 0.0026, respectively), also improved significantly. Laboratory supervision for malaria diagnosis found significant areas for improvement, and in combination with concurrent capacity-building activities, it improved the diagnostic capacity for malaria and other diseases. Importantly, this study demonstrates that locally available resources can be used to improve the accuracy of malaria diagnosis.

  6. Critical and strategic materials proceedings of the laboratory study group meeting

    Energy Technology Data Exchange (ETDEWEB)

    1983-06-01

    These Proceedings serve to identify the appropriate role for the DOE-BES-DMS Laboratory program concerning critical and strategic materials, identify and articulate high priority DOE-BES-DMS target areas so as to maximize programmatic responsiveness to national needs concerning critical and strategic materials, and identify research, expertise, and resources (including Collaborative Research Centers) that are relevant to critical and strategic materials that is either underway or in place under the DOE-BES-DMS Laboratory program. Laboratory statements of collaborative research are given.

  7. Feasibility study on introduction of KOLAS (Korea Laboratory Accreditation Scheme) in nuclear examination facility

    Energy Technology Data Exchange (ETDEWEB)

    Park, Dae Gyu; Hong, K. P.; Song, W. S.; Min, D. K

    1999-07-01

    To be an institute officially authorized by the KOLAS, the understanding and the analysis of following contents is required.: the understanding of concept required to get the accreditation of testing, the system specifying an internationally accredited testing and examination organization, international organization in the field of laboratory accreditation, domestic laboratory accreditation organization(KOLAS), the investigation of the regulations with laboratory accreditation in Korea, the investigation of the procedures accrediting a testing and examination organization, the investigation of general requirements(ISO 17025) for a testing and examination organization. (author)

  8. Correlation of liquefaction resistance with shear wave velocity based on laboratory study using bender element

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yan-guo; CHEN Yun-min; KE Han

    2005-01-01

    Recent studies using field case history data yielded new criteria for evaluating liquefaction potential in saturated granular deposits based on in situ, stress-corrected shear wave velocity. However, the conditions of relatively insufficient case histories and limited site conditions in this approach call for additional data to more reliably define liquefaction resistance as a function of shear wave velocity. In this study, a series of undrained cyclic triaxial tests were conducted on saturated sand with shear wave velocity Vs measured by bender element. By normalizing the data with respect to minimum void ratio, the test results, incorporated with previously published laboratory data, statistically revealed good correlation of cyclic shear strength with small-strain shear modulus for sandy soils, which is almost irrespective of soil types and confining pressures. The consequently determined cyclic resistance ratio, CRR, was found to be approximately proportional to Vs4. Liquefaction resistance boundary curves were established by applying this relationship and compared to liquefaction criteria derived from seismic field measurements. Although in the range of Vs1>200 m/s the presented curves are moderately conservative, they are remarkably consistent with the published field performance criteria on the whole.

  9. Laboratory study on metal attenuation capacity of fine grained soil near ash pond site.

    Science.gov (United States)

    Ghosh, Sudipta; Mukherjee, Somnath; Sarkar, Sujoy; Kumar, Sunil

    2008-10-01

    Waste settling tanks of earthen containment nature are common in India for disposal of solid waste in slurry form. For a large pond system, e.g. ash slurry disposal tank of coal base thermal power plant, leachate generation and its migration pose a serious problem. A natural attenuation of controlling the migratory leachate is to use locally available clay material as lining system due to the adsorption properties of soil for reducing some metallic ions. The present investigation was carried out to explore the Ni2+ and Cr6+ removal capacity of surrounding soil of the ash pond site of Super Thermal Power Plant in West Bengal, India through some laboratory scale and field studies. The soil and water samples collected from the site showed the existence of Ni2+ and Cr6+ in excess to permissible limit. A two-dimensional adsorption behaviour of these pollutants through soil was assessed. The results showed that more than 80% of nickel and 72% of chromium were found to be sorbed by the soil corresponding to initial concentrations of two ions, i.e. 1.366 mg/L and 0.76 mg/L respectively. The batch adsorption data are tested Langmuir and Freundlich isotherm models and found reasonably fit. Breakthrough adsorption study uptake also showed a good adsorption capacity of the soil. The experimental results found to fit well with the existing two dimensional (2D) mathematical models as proposed by Fetter (1999).

  10. Computed tomography study of VAPEX process in laboratory 3D model

    Energy Technology Data Exchange (ETDEWEB)

    Wu, G.Q.; Kantzas, A. [Calgary Univ., AB (Canada). Tomographic Imaging and Porous Media Laboratory; Salama, D. [Nexen Inc., Calgary, AB (Canada)

    2008-07-01

    This paper provided details of a 3-D laboratory model of the VAPEX process that used computerized tomography (CT) to examine vapour chamber expansion behaviour in longitudinal and radial directions. The model was comprised of an aluminum cylinder with 2 slotted tubes installed inside to act as injection and production wells. Propane was used as a solvent with heavy oil. The results of experiments conducted with the model showed that the V shape vapour chamber expansion pattern predicted by the 2-D model was a localized phenomenon. The dominant characteristic of the vapour chamber was an overriding of the injected solvent at the top of the model. The overriding was attributed to gravity segregation. The study also showed that longitudinal expansion was more significant than upwards expansion during the early stages of the VAPEX process. Oil production performance was then examined using different solvent injection rates. An analysis of the CT images was conducted to obtain model porosity, density, and oil saturation profiles. The study demonstrated that pressure cycles caused oil to be produced intermittently. Oil swelling by solvent gas dissolution was an important recovery mechanism. It was concluded that solvent soaking can be used to recover additional residual oil during the VAPEX process. 19 refs., 1 tab., 24 figs.

  11. COMPARATIVE DEMOGRAPHICS OF A GENERALIST PREDATORY LADYBIRD ON FIVE APHID PREY: A LABORATORY STUDY

    Institute of Scientific and Technical Information of China (English)

    Omkar; AhmadPervez

    2004-01-01

    Prey driven demographic parameters of an aphidophagous ladybird, Propylea dissecta (Mulsant) were studied in attempt to answer how ladybird overcomes the problem of seasonally fluctuating food base. The ladybird reared for five generations in laboratory derived differential nutrition from five food sources (i.e. aphid species, Rhopalosiphum maidis (Fitch), Aphis craccivora Koch, Aphis gossypii Glover, Uroleucon compositae (Theobald) and Lipaphis erysimi (Kalt.)). The order of relative prey suitability was A. gossypii, A. craccivora, R. maidis, U. compositae and L.erysimi. Neonates suffered maximum mortality followed by eggs. Estimates of net reproductive rate,intrinsic rate of increase and finite rate of increase were highest (407.18, 0.2274 day-1, 1.2553 day-1) on A. gossypii and lowest (176.02, 0.1533 day-1, 1.1657 day-1) on L. erysimi. Generation time was shortest (26.43 days) on A. gossypii and longest (33.73 days) on L. erysimi. The present study thus,provides an explanation to the high incidence of P. dissecta on A. gossypii, as it experienced high intrinsic rate of increase and optimal values for related demographic parameters.

  12. Algal assay research in programs for Euthrophic Lake management: laboratory and field studies

    Energy Technology Data Exchange (ETDEWEB)

    Lindmark, G.

    1979-01-01

    The present study is an attempt to clarify whether relations between viruses (cyanophages) and their algal hosts can be affected by manipulations in the environment. Is is possible to activate cyanophages and accelerate lysis of blue-green algal populations or to enhance the resistance of blue-green algae to attack from cynaophages. The experiments presented here were performed under laboratory conditions with a well-known algal - canophage system, Plectonema boryanum and cyanophage LPP-1 (attacking strains of Lyngbya, Phormidium and Plectonema). The work was done in close connection with field experiments on natural blue-green algal communities, however, because the nature of the induced blue-green algal collapse in plastic enclosures suggested lysis of the algal cells. The rate of LPP-1 cyanophage replication and lysis of plectonema was studied in relation to: (a) pH alterations by CO/sub 2//air additions, (b) algal host culture age and density, (c) nutrient concentrations and (d) presence of additional algal species.

  13. Target studies for the neutrino factory at the Rutherford Appleton laboratory

    CERN Document Server

    Drumm, P V; Bennett, R

    2001-01-01

    Target studies at the Rutherford Appleton Laboratory have concentrated on studies of a solid heavy metal target. The suggestion to use a radiatively cooled target which rotates in beam was made shortly after the first NuFact workshop as a means of dissipating large amounts of power at a high temperature, and as an alternative to the proposed water-cooled rotating band and liquid metal jet targets. This paper examines the proposed drive scheme for the target ring, which uses induced currents and magnetic forces to both levitate and drive the target. Estimates of the power required to levitate and drive the target ring and the forces exerted on the moving ring as it enters the target capture solenoid are given. One of the principle concerns in the operation of a solid target is the severe shock stress experienced due to the impact of an intense energetic proton beam in a short time compared to the transit time of sound in the material. Calculations of the stresses induced in the target ring and their evolution ...

  14. Laboratory and field studies of polonium and plutonium in marine plankton

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, R.C. [Westlakes Scientific Consulting Ltd., Princess Royal Building, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3LN (United Kingdom)], E-mail: richard.c.wilson@westlakes.ac.uk; Watts, S.J.; Vives i Batlle, J.; McDonald, P. [Westlakes Scientific Consulting Ltd., Princess Royal Building, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3LN (United Kingdom)

    2009-08-15

    Uptake experiments were successfully undertaken for polonium and plutonium in the marine diatom Skeletonema costatum. Experiments were complemented with a field study which yielded concentration factors for these radionuclides for plankton samples collected in the eastern Irish Sea. The uptake experiment produced uptake half times of 0.8 and 0.6 days for plutonium and polonium, respectively. Concentration factors of 3.1 x 10{sup 5} l kg{sup -1} for plutonium and 2.4 x 10{sup 5} l kg{sup -1} for polonium were consistent with those suggested by the IAEA for phytoplankton. Concentration factors derived from the field study were 2 x 10{sup 3} l kg{sup -1} for plutonium and 1.4 x 10{sup 4} l kg{sup -1} for polonium and were more consistent with IAEA values for zooplankton rather than phytoplankton. The maximum calculated dose rate due to Po and Pu in plankton sampled in the field was 0.12 {mu}Gy h{sup -1}. In applying the laboratory-derived phytoplankton CF values for Po and Pu, higher dose rates, in the range 6-11 {mu}Gy h{sup -1}, were calculated. The latter values are well below the UNSCEAR and IAEA review value of 400 {mu}Gy h{sup -1}, and are also below the Environment Agency marine action level of 40 {mu}Gy h{sup -1}.

  15. Studies on corrosion control of naphtha fractions in overhead condensing system using laboratory distillation device

    Energy Technology Data Exchange (ETDEWEB)

    Saxena, R.C.; Jayaraman, A.; Chauhan, R.K; Goyal, H.B. [Indian Institute of Petroleum, Dehradun-248005 (India)

    2010-10-15

    Corrosion in the overhead condensing system of atmospheric distillation units is a common occurrence in petroleum refineries worldwide. These corrosion problems are influenced by the presence of three phases: vapours, liquid hydrocarbons and aqueous phase containing hydrochloric acid formed during distillation by decomposition of chloride salts of calcium and magnesium. Present studies highlight the corrosion control of naphtha fractions of Bombay High and Dubai crude oils in laboratory distillation device by chemical treatment using various corrosion inhibitors having different functional groups. These studies were carried out using two phase systems (aqueous-hydrocarbon) in the distillation device having facilities for monitoring the corrosion and temperatures in vapour condensing region and liquid condensate. Corrosion monitoring was carried out by potentiodynamic polarization technique and dissolved iron analysis using inductively coupled plasma atomic emission spectroscopy (ICPAES). Experimental findings indicate that Dubai naphtha fraction is more corrosive in nature when compared to Bombay High naphtha. This observation can also be explained on the basis of characterization of both crude oils and their naphtha fractions. At normally recommended dosage level as in refinery overhead systems, water soluble corrosion inhibitors are more effective than hydrocarbon soluble ones in the vapour condensing region as well as in the liquid condensate of both naphtha fractions. (author)

  16. Comparative laboratory studies of well treatment techniques based on in situ cross linking and polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Lakatos, I.; Kiss, G.M.; Lakatos, S.J.

    1982-01-01

    In order to improve the water oil ratio in operating oil wells in 1972-1978, a number of methods were developed and tested based on treating the well with polymers. Under laboratory conditions methods were studied that were based on processes occurring in situ of cross linking of polymers by multivalent cations and polymerization of monomer solutions. The polymers used were different types of polyacrylamide, and the monomers were acrylamide and N, N-methylenebis-acrylamide. The effect of the forming gel on permeability was studied on the linear section of the nonconsolidated porous material, and on the change in water-oil ratio in radial geometry on a sandstone core sample. Comparative analysis of the methods indicated that the upper limit of the temperature stability of the gel bonded by multivalent cations does not exceed 80-100/sup 0/C. The effectiveness of the method can be considerably improved by adding aliphatic alcohols or by using polymer-silicate systems. The main advantage of the method of polymerization in situ as compared to the indicated method is higher temperature of gel stability (up to 100/sup 0/C and higher). In this case gel formation does not depend on the process of dispersion, occurs in the complete volume of the injected fluid, and the gel parameters can be regulated in broad limits. Of use of the methods of in situ polymerization should be preceded by an economic evaluation of work under specific conditions.

  17. Laboratory and field studies concerning the long-term storage of elemental sulfur

    Energy Technology Data Exchange (ETDEWEB)

    Davis, P.M.; Clark, P.D.; Bernard, F. [Alberta Sulfur Research Ltd., Calgary, AB (Canada)]|[Calgary Univ., Calgary, AB (Canada)

    2004-07-01

    Canadian sour gas processing facilities supply much of the elemental sulfur to the international market. Elemental sulfur is a pure commodity obtained when hydrogen sulfide is removed from raw gases by way of the Claus process. Excess production is usually stored above ground as a bulk solid at the processing facility. It is possible that sulfur may have to be stored in large quantities if a market imbalance may occurs due to expanding exploration in sulfur-bearing formations and increasing regulations on sulfur levels in processing effluents. For that reason, long-term storage methods are being examined in detail. Both above and below ground block storage is considered environmentally acceptable for sulfur storage as long as measures are taken to minimize the physical and biological breakdown of the sulfur. The main concern regarding above ground storage is the generation of sulfur dust from phase transformations within the sulfur itself. Other concerns include acid production from bacterial activity and the weathering of the material when it is exposed to the elements over the long-term. This paper addresses these concerns and presents results from a series of research studies on underground storage of elemental sulfur both in the laboratory and in pilot-scale field studies.

  18. Homogeneity study of a corn flour laboratory reference material candidate for inorganic analysis.

    Science.gov (United States)

    Dos Santos, Ana Maria Pinto; Dos Santos, Liz Oliveira; Brandao, Geovani Cardoso; Leao, Danilo Junqueira; Bernedo, Alfredo Victor Bellido; Lopes, Ricardo Tadeu; Lemos, Valfredo Azevedo

    2015-07-01

    In this work, a homogeneity study of a corn flour reference material candidate for inorganic analysis is presented. Seven kilograms of corn flour were used to prepare the material, which was distributed among 100 bottles. The elements Ca, K, Mg, P, Zn, Cu, Fe, Mn and Mo were quantified by inductively coupled plasma optical emission spectrometry (ICP OES) after acid digestion procedure. The method accuracy was confirmed by analyzing the rice flour certified reference material, NIST 1568a. All results were evaluated by analysis of variance (ANOVA) and principal component analysis (PCA). In the study, a sample mass of 400mg was established as the minimum mass required for analysis, according to the PCA. The between-bottle test was performed by analyzing 9 bottles of the material. Subsamples of a single bottle were analyzed for the within-bottle test. No significant differences were observed for the results obtained through the application of both statistical methods. This fact demonstrates that the material is homogeneous for use as a laboratory reference material. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Production behaviour of gas hydrate under hot sea water injection : laboratory case study

    Energy Technology Data Exchange (ETDEWEB)

    Nengkoda, A. [Schlumberger, Calgary, AB (Canada); Budhijanto, B.; Supranto, S.; Prasetyo, I.; Purwono, S.; Sutijan, S. [Gadjah Mada Univ., Yogyakarta (Indonesia)

    2010-07-01

    The gas hydrate potential in Indonesia was discussed, with particular reference to offshore production of gas from deep-water gas-hydrates by injection of hot seawater. In 2004, the Indonesian National Agency for Assessment and Application Technology estimated the gas hydrate resource potential to be 850 trillion cubic feet (tcf). To date, the 3 most reliable scenarios for gas hydrate production are thermal stimulation which involves increasing the temperature until the hydrates break into water and gas; depressurization which involves lowering the pressure by pumping out gas at the base of the hydrate to cause dissociation of hydrates into gas; and injection of a chemical inhibitor such as methanol into the hydrated sediments to cause destabilization, thus releasing gas from hydrates. This study investigated the effect of hot seawater injection on the gas hydrate production under laboratory conditions. The temperature profile distribution was examined along with operational parameters and flow characteristics of the dissociated gas and water from hydrates in porous systems under a synthetic hydrate setup. The study showed that gas production increases with time until a maximum is reached, at which time it begins to decrease. The energy ratio of thermal stimulation production was found to be influenced by the injection water temperature and rate as well as the hydrate content in the synthetic sediment. Scale problems were found to be associated with high temperature seawater injection. 8 refs., 3 tabs., 7 figs.

  20. Laboratory feasibility study of a composite embedded fiber optic sensor for measurement of structural vibrations

    Science.gov (United States)

    Dube, C. M.; Wang, Tom D.; Melton, Robert G.; Jenson, David W.; Koharchik, Mike

    1988-02-01

    The feasibility is assessed of using fiber optic strain sensors embedded in a composite material to measure the magnitude and frequency of structural vibrations for control of flexible elements. This study demonstrates the ability to embed fiber optic strain sensors in a composite material, determines the performance of these sensors, identifies active control system architectures that are matched to the fiber optic system measurands to damp vibrations of large space structures, and estimates the stability achievable by these methods. A detailed laboratory study was performed using a wide band closed-loop-fiber Mach-Zehnder interferometer to conduct transverse vibration measurements on sub-scale composite elements with embedded fiber sensors. The interferometer detects vibrations by measuring the strain transferred by the composite to the embedded optical fiber. The strain sensor demonstrated the ability to track the vibrations of a cantilever beam over a frequency bandwidth ranging from approximately 5 Hz to almost 1000 Hz. The sensor was unable to detect dc strains because of thermal drift and laser power fluctuations. These factors produced a drift in the dc signal level, which was indistinguishable from static strain measurements. Beyond 1000 Hz, the composite element was unable to follow the drive mechanism. The noise equivalent strain was epsilon is approximately 10 to the minus 10th power.

  1. Application of dissolved air flotation process for industrial sludge thickening: A laboratory-scale study

    Directory of Open Access Journals (Sweden)

    Ali Atamaleki

    2017-01-01

    Full Text Available Aims: Increasing population density in cities has led to an increase in industrial and municipal wastewater sludge generation volume. Dissolved air flotation (DAF can widely be used for water and wastewater treatment. The aim of our study is to evaluate some DAF design parameters on biological sludge thickening which generated from an industrial wastewater treatment plant. Materials and Methods: This experimental research had been carried out as a laboratory-scale study on DAF process to thickening of the biological sludge. The required amount of sludge was taken once from the Amikabir industrial town wastewater treatment plant in Kashan, Iran. After determination of optimal recycling rate, pH, and coagulant dose, effects of pressure (3, 5, and 7 atm, flotation time (5 and 10 min, and coagulant addition were evaluated on DAF process efficiency. Results: According to this investigation results, the optimal pH and dose of coagulant were obtained 7.5 and 200 mg/L, respectively. Maximum process efficiency for the reduction of total dissolved solids (TDSs, total solids (TSs, and turbidity parameters was 61.01%, 84.02%, and 97%, respectively. Furthermore, the results showed that in contrast to time, coagulant addition and pressure have significant effect on DAF process. Conclusion: DAF process had suitable thickening efficiency to removal of TDS, TS, and turbidity on biological activated sludge.

  2. Laboratory and field studies of polonium and plutonium in marine plankton.

    Science.gov (United States)

    Wilson, R C; Watts, S J; Vives i Batlle, J; McDonald, P

    2009-08-01

    Uptake experiments were successfully undertaken for polonium and plutonium in the marine diatom Skeletonema costatum. Experiments were complemented with a field study which yielded concentration factors for these radionuclides for plankton samples collected in the eastern Irish Sea. The uptake experiment produced uptake half times of 0.8 and 0.6 days for plutonium and polonium, respectively. Concentration factors of 3.1 x 10(5) l kg(-1) for plutonium and 2.4 x 10(5) l kg(-1) for polonium were consistent with those suggested by the IAEA for phytoplankton. Concentration factors derived from the field study were 2 x 10(3) l kg(-1) for plutonium and 1.4 x 10(4) l kg(-1) for polonium and were more consistent with IAEA values for zooplankton rather than phytoplankton. The maximum calculated dose rate due to Po and Pu in plankton sampled in the field was 0.12 microGyh(-1). In applying the laboratory-derived phytoplankton CF values for Po and Pu, higher dose rates, in the range 6-11 microGyh(-1), were calculated. The latter values are well below the UNSCEAR and IAEA review value of 400 microGyh(-1), and are also below the Environment Agency marine action level of 40 microGyh(-1).

  3. Probing Photochemistry in the Quasi-Liquid Layer: Laboratory Studies and Implications for OASIS Processes

    Science.gov (United States)

    Mahanna, K. M.; Greis, V.; Grannas, A. M.

    2005-12-01

    Recent studies illustrate the previously overlooked importance of snow and ice as reactive chemical media in the environment. It has been shown that the Arctic snowpack plays an important role in processing atmospheric species such as mercury, nitrogen oxides, alkyl halides, ozone, carbonyl compounds and molecular halogens. Photochemical transformations of anthropogenic organic contaminants in ice also have been observed, although published information regarding these processes is scant. It has been shown that a liquid-like (quasi-liquid or disordered) layer exists on the surface of pure ice and that a quasi-liquid layer (QLL) is also found on the surface of ambient snow crystals and ice at temperatures relevant to polar conditions. It is unclear what role the QLL on the surface of snow/ice plays in potential photochemical reactions. Here we report results of recent laboratory studies of photochemistry occurring in the QLL. We used the well characterized reaction of p-nitroanisole with pyridine to probe changes in photochemistry that may occur upon freezing. We found that freezing greatly enhanced the rate of this particular reaction (the half-life of the reaction was 20 times shorter when the solution was frozen). Additionally, we could alter the half-life in predictable ways by changing variables such as ionic strength and temperature. The findings of these experiments will be discussed as well as the potential implications to ocean-air-sea ice-snow (OASIS) interactions of organic pollutants in polar climates.

  4. Laboratory Study on Biological Control of Ticks (Acari: Ixodidae by Entomopathogenic Indigenous Fungi (Beauveria bassiana

    Directory of Open Access Journals (Sweden)

    M Abdigoudarzi

    2009-12-01

    Full Text Available Background: Chemical control method using different acaricides as spray, dipping solution or pour-on is routinely used for controlling ticks. Biological control agents are favorable due to their safety for animals and environment. Entomopathogenic fungi such as Beauveria bassiana are well known for controlling ticks. In this study, two Iranian indigenous strains of B. bassiana (B. bassiana 5197 and B. bassiana Evin were selected and grown on specific me­dia. The pathogenic effects of these strains were evaluated on adult stages of two Iranian Ixodidae members (H. anatolicum anatolicum Koch 1844, and H. marginatum Koch 1844 by dipping method.Methods: Two Iranian strains of Beauveria bassiana (Beauveria bassiana 5197 and Beauveria bassiana Evin were selected and were grown successfully on specific media. The pathogenic effects of these strains were evaluated on adult stages of Iranian Ixodidae members such as, Hyalomma anatolicum anatolicum and H. marginatum by dipping method (these ticks were grown up at laboratory conditions during 2002 up to 2003 and still it is continued .Results: There was no effect of strain 5197 on mortality or fecundity rates for ticks. There was acute phase sign of paralysis in test group after dipping ticks in suspension made from Evin strain of B. bassiana. In addition, the test groups were totally died after four months, but the control groups survived for six months.Conclusion: High concentration of fungal spores is needed for inducing fungal infection. Additional study using different strains and fungi on Iranian ticks is proposed. 

  5. The relationship between craving and tobacco use behavior in laboratory studies: a meta-analysis.

    Science.gov (United States)

    Gass, Julie C; Motschman, Courtney A; Tiffany, Stephen T

    2014-12-01

    Published laboratory studies from the last 50 years that included measures of craving and tobacco-consumption or tobacco-seeking measures were included in a meta-analysis in order to assess the relationship between craving and tobacco use. Seeking measures were further subdivided into those that reflected control by nonautomatic and automatic cognitive processes. Of 2,498 articles identified by the initial literature review, 204 analyses from 50 studies were deemed eligible. Overall, the relationship between craving and outcome behaviors was modest (r = .20, p craving and outcome (r = .24, p craving and outcome was stronger for smokers who were less dependent. Separate meta-analyses revealed that the type of outcome measure moderated the omnibus effect, with the relationship between craving and nonautomatic seeking measures (r = .34, p craving and automatic seeking/consumption measures (both rs = 0.15, p craving may play a role in, but does not fully account for, tobacco-use behaviors; furthermore, the extent to which craving predicts behavior may be increased when the behavior is under nonautomatic cognitive control.

  6. West Florida Shelf: A natural laboratory for the study of ocean acidificiation

    Science.gov (United States)

    Hallock, Pamela; Robbins, Lisa L.; Larson, Rebekka A.; Beck, Tanya; Schwing, Patrick; Martinez-Colon, Michael; Gooch, Brad

    2010-01-01

    Declining oceanic pH and carbonate-ion concentrations are well-known consequences of increased atmospheric and surface-ocean partial pressure of carbon dioxide (pCO2). The possible subject of shifts in seawater carbonate chemistry on biocalcification and survival rates of marine organisms provides questions amenable to both experimental and field study (Kleypas and Langdon, 2006). To date, limited quantitative data exist with which to formalize and test hypotheses regarding such impacts, particularly in continental-shelf settings. The continental shelves of Florida provide an ideal natural laboratory in which to test latitudinal (and temperature and depth) shifts in habitat ranges of calcifying organisms. Both the east and west Florida shelves extend from warm temperate to subtropical latitudes; additionally, the west Florida shelf has very little siliciclastic influx to mask the carbonate production. This study utilizes the natural laboratory of the west and southwest Florida shelf (fig 1.1) to examine the transition from foramol (predominately foraminifera and molluscan) carbonate sediments, characteristic of the west-central Florida shelf, to chlorozoan (algal and coral) sediments characteristic of the southwest Florida shelf. The west Florida shelf is a mixed siliciclastic carbonate ramp that to the south transitions to the carbonate-dominated southwest Florida shelf (Enos, 1977; Brooks and others, 2003). The west Florida shelf is a distally steepened carbonate ramp that is ~250 kilometers (km) wide (Read, 1985). It is covered by a veneer of unconsolidated sediment consisting of mainly biogenic carbonate and quartz in the near shore, with subordinate amounts of phosphate. The sediment-distribution pattern is largely a function of proximity to source, with physical processes playing a minor role in distribution. The carbonate sand-and-gravel fraction is produced by organisms within the depositional basin of the west Florida shelf (Brooks and others, 2003). The

  7. Chemical aging of m-xylene secondary organic aerosol: laboratory chamber study

    Directory of Open Access Journals (Sweden)

    J. H. Seinfeld

    2011-09-01

    Full Text Available Secondary organic aerosol (SOA can reside in the atmosphere for a week or more. While its initial formation from the gas-phase oxidation of volatile organic compounds tends to take place in the first few hours after emission, SOA can continue to evolve chemically over its atmospheric lifetime. Simulating this chemical aging over an extended time in the laboratory has proven to be challenging. We present here a procedure for studying SOA aging in laboratory chambers that is applied to achieve 36 h of oxidation. The formation and evolution of SOA from the photooxidation of m-xylene under low-NOx conditions and in the presence of either neutral or acidic seed particles is studied. In SOA aging, increasing molecular functionalization leads to less volatile products and an increase in SOA mass, whereas gas-phase or particle-phase fragmentation chemistry results in more volatile products and a loss of SOA. The challenge is to discern from measured chamber variables the extent to which these processes are important for a given SOA system. In the experiments conducted, m-xylene SOA mass increased over the initial 12-h of photooxidation and decreased beyond that time. The oxidation of the SOA, as manifested in the O:C elemental ratio and fraction of organic ion detected at m/z 44 measured by the Aerodyne aerosol mass spectrometer, decreased during the first 5 h of reaction, reached a minimum, and then increased continuously until the 36 h termination. This behavior is consistent with an initial period in which, as the mass of SOA increases, products of higher volatility partition to the aerosol phase, followed by an aging period in which gas- and particle-phase reaction products become increasingly more oxidized. After about 12–13 h, the SOA mass reaches a maximum and decreases, suggesting the existence of fragmentation chemistry. When irradiation is stopped 12.4 h into one experiment, and OH generation ceases, no loss of SOA is observed, indicating

  8. Optimal Questions for Sleep in Epidemiological Studies: Comparisons of Subjective and Objective Measures in Laboratory and Field Studies.

    Science.gov (United States)

    Croy, Ilona; Smith, Michael Gerard; Gidlöf-Gunnarsson, Anita; Persson-Waye, Kerstin

    2017-01-01

    Epidemiological studies on sleep often use questionnaires, and measurement of validity provides necessary guidance in selection of valid single sleep questions. Twenty-five items assessing different aspects of sleep, including overall sleep quality, specific sleep parameters, nocturnal restoration, and exposure-related questions, were tested. This involved coherence with objective polysomnographic (PSG) laboratory measurements of sleep in 47 participants and application of selected items under field conditions in over 3,000 participants. Items on overall sleep quality correlated significantly with PSG data. For specific sleep parameter questions, tiredness in the morning, time to fall asleep, difficulties to sleep and estimated number of awakenings were correlated to PSG data. Questions asking specifically about the effect of potential sleep disturbances correlated poorly with PSG data, but showed highest effects between environmental exposure (noise and vibration) and control nights in the laboratory and highest correlation with the dose of exposure in the field. In conclusion, healthy participants seem to be able to access their sleep reliably; and sleep questions asking about specific sleep parameters can be recommended for the assessment of sleep.

  9. Photometrics Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose:The Photometrics Laboratory provides the capability to measure, analyze and characterize radiometric and photometric properties of light sources and filters,...

  10. Blackroom Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Enables evaluation and characterization of materials ranging from the ultraviolet to the longwave infrared (LWIR).DESCRIPTION: The Blackroom Laboratory is...

  11. Target Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — [Part of the ATLAS user facility.] The Physics Division operates a target development laboratory that produces targets and foils of various thickness and substrates,...

  12. Target Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — [Part of the ATLAS user facility.] The Physics Division operates a target development laboratory that produces targets and foils of various thickness and substrates,...

  13. Blackroom Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Enables evaluation and characterization of materials ranging from the ultraviolet to the longwave infrared (LWIR). DESCRIPTION: The Blackroom Laboratory is...

  14. IN-SERVICE HYDRAULIC CONDUCTIVITY OF GCLS IN LANDFILL COVERS - LABORATORY AND FIELD STUDIES

    Science.gov (United States)

    Laboratory experiments using multi-species inorganic solutions (containing calcium and sodium) were conducted on specimens of a new geosynthetic clay liner (GCL) containing sodium bentonite to determine how cation exchange and desiccation affected the hydraulic conductivity. Calc...

  15. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres

    Energy Technology Data Exchange (ETDEWEB)

    Hopke, P.K.

    1992-07-01

    This report describes studies on the chemical and physical behavior of the [sup 218]Po atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity in the sub-10 nm size range result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and its dose to the cells in the respiratory tract are to be fully assessed. The specific tasks of the controlled laboratory studies are to determine the formation rates of [center dot]OH radicals formed by the radiolysis of air following radon decay, to examine the formation of particles by the radiolytic oxidation of substances like SO[sub 2] ethylene, and H[sub 2]S to lower vapor pressure compounds and determine the role of gas phase additives such as H[sub 2]O and NH[sub 3] in determining the particle size, to measure the rate of ion-induced nucleation using a thermal diffusion cloud chamber, and to measure the neutralization rate of [sup 218]Po[sub x][sup +] in O[sub 2] at low radon concentrations. Tasks of the exposure studies in occupied indoor spaces are to initiate measurements of the activity size distributions in actual homes with occupants present so that the variability of the indoor activity size distributions can be assessed with respect to indoor aerosol sources and general lifestyle variations of the occupants, to initiate a prospective study of the utility of measurement of deposited [sup 210]Pb embedded in glass surfaces as a measure of the long-term, integrated exposure of the population to radon, and to develop the methodology to determine the hygroscopicity of the indoor aerosol so that the changes in deposition efficiency of the radioactive indoor aerosol with hygroscopic growth in the respiratory tract can be assessed.

  16. Laboratory Studies of Phosphine Chemistry Relevant to the Jovian and Saturnian Atmospheres

    Science.gov (United States)

    Liu, Yingdi; Matsiev, Daniel; Robertson, Robert; White, Jason

    2016-10-01

    The photochemistry of phosphine (PH3) in the tropospheres of Saturn and Jupiter is initiated by ultraviolet (UV) radiation and then follows a cascade of chemical reactions that result in P-H hydrides as well as the condensed chromophore red phosphorus (P4). A key intermediate in this pathway is diphosphine (P2H4). The rate constants for the photodissociation of phosphine into initial phosphino radicals and consequently into formation of diphosphine are currently unavailable, limiting their applicability to observational measurements. The condensation of diphosphine to ice in the cold tropospheres is also poorly understood due to the difficulties in synthesizing, handling, and analyzing the compound.Our presentation will describe two experiments at SRI International to produce rate constants for the photochemistry initiated by UV light interacting with phosphine and diphosphine and properties related to the condensed phases of these species. One study seeks to produce property values for application in photochemical and cloud/haze models. Specifically, we extend the measured vapor pressure curve for diphosphine to temperatures relevant to temperatures of Saturn and Jupiter. A sophisticated vapor pressure cell has been constructed and tested and is coupled to a Fourier transform infrared (FTIR) and mass spectrometer for high-fidelity species diagnostics. A companion study investigates phosphine photochemistry to measure the rate constants of key intermediate species related to the loss of PH3 and the formation of P2H4. The experiments employ laser photolysis at 193 nm followed by time-resolved mid-IR laser-based species detection of reactants, and the products provide basic chemical kinetic data useful for interpreting phosphine photochemistry in planetary atmospheres.These two studies are intended to supply basic physical measurements to aid in the interpretation of outer planet atmospheric observations. For both studies, we will present our latest laboratory

  17. Technology study of Gunite tank sludge mobilization at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    DeVore, J.R.; Herrick, T.J.; Lott, K.E.

    1994-12-01

    The Oak Ridge National Laboratory (ORNL) Gunite Tank Sludge Mobilization Technology Study was initiated to support the Gunite Tank Treatability Study effort. The technology study surveyed the methods and technologies available for tank cleaning and sludge mobilization in a radioactive environment. Technologies were identified and considered for applicability to the Gunite and Associated Tanks (GAAT) problems. These were then either accepted for further study or rejected as not applicable. Technologies deemed applicable to the GAAT sludge removal project were grouped for evaluation according to (1) deployment method, (2) types of remotely operated end effector equipment applicable to removal of sludge, (3) methods for removing wastes from the tanks, and (4) methods for concrete removal. There were three major groups of deployment technologies: ``past practice`` technologies, mechanical arm-based technologies, and vehicle-based technologies. The different technologies were then combined into logical sequences of deployment platform, problem, end effector, conveyance, post-removal treatment required (if any), and disposition of the waste. Many waste removal options are available, but the best technology in one set of circumstances at one site might not be the best type to use at a different site. No single technology is capable of treating the entire spectrum of wastes that will be encountered in GAAT. None of the systems used in other industries appears to be suitable, primarily because of the nature of the sludges in the GAAT Operable Unit (OU), their radiation levels, and tank geometries. Other commercial technologies were investigated but rejected because the authors did not believe them to be applicable.

  18. Choice of experimental venue matters in ecotoxicology studies: Comparison of a laboratory-based and an outdoor mesocosm experiment.

    Science.gov (United States)

    Mikó, Zsanett; Ujszegi, János; Gál, Zoltán; Imrei, Zoltán; Hettyey, Attila

    2015-10-01

    The heavy application of pesticides and its potential effects on natural communities has attracted increasing attention to inadvertent impacts of these chemicals. Toxicologists conventionally use laboratory-based tests to assess lethal concentrations of pesticides. However, these tests often do not take into account indirect, interactive and long-term effects, and tend to ignore different rates of disintegration in the laboratory and under natural conditions. Our aim was to investigate the importance of the experimental venue for ecotoxicology tests. We reared tadpoles of the agile frog (Rana dalmatina) in the laboratory and in outdoor mesocosms and exposed them to three initial concentrations of a glyphosate-based herbicide (0, 2 and 6.5 mg a.e./L glyphosate), and to the presence or absence of caged predators (dragonfly larvae). The type of experimental venue had a large effect on the outcome: The herbicide was less lethal to tadpoles reared in outdoor mesocosms than in the laboratory. Further, while the herbicide had a negative effect on development time and on body mass in the laboratory, tadpoles exposed to the herbicide in mesocosms were larger at metamorphosis and developed faster in comparison to those reared in the absence of the herbicide. The effect of the herbicide on morphological traits of tadpoles also differed between the two venues. Finally, in the presence of the herbicide, tadpoles tended to be more active and to stay closer to the bottom of laboratory containers, while tadpole behaviour shifted in the opposite direction in outdoor mesocosms. Our results demonstrate major discrepancies between results of a classic laboratory-based ecotoxicity test and outcomes of an experiment performed in outdoor mesocosms. Consequently, the use of standard laboratory tests may have to be reconsidered and their benefits carefully weighed against the difficulties of performing experiments under more natural conditions. Tests validating experimentally estimated

  19. Optimization of an animal test protocol for toxicogenomics studies (ii); a cross-laboratory gene expression analysis.

    Science.gov (United States)

    Sumida, Kayo; Saito, Koichi; Oeda, Kenji; Otsuka, Masanori; Tsujimura, Kazunari; Miyaura, Hideki; Sekijima, Masaru; Nakayama, Koji; Kawano, Yukiko; Kawakami, Yuki; Asamoto, Makoto; Shirai, Tomoyuki

    2007-02-01

    Toxicogenomics is a promising new tool for prediction of chemical toxicities including carcinogenicity in a relatively short period. However, it is important to develop a reliable animal test protocol for toxicogenomics studies. The preparation of RNA and tissues is also crucial, since it greatly influences outcomes of gene expression analysis. We proposed an animal test protocol for toxicogenomics studies. In the present study, we examined an animal test protocol by comparing biological and gene expression data from different laboratories running identical in vivo studies on the same microarray platform. The results gave good correspondence in all three laboratories at the level of biological responses and gene expression, especially for genes whose expression changes were quite large. As the fold change or the signal values become smaller, however, discrepancies occur in gene expression data. For example, one laboratory shows an opposite directional change to the other two or no change. The results of hierarchical clustering and principal component analysis (PCA) demonstrated all samples from the three laboratories being clearly divided between control and treatment. Examination of the reproducibility of gene expression data across laboratories using the proposed animal test protocol thus confirmed only minor differences, which was expected to present no problems for gene expression analysis.

  20. Absorbing Aerosols: Field and Laboratory Studies of Black Carbon and Dust

    Science.gov (United States)

    Aiken, A. C.; Flowers, B. A.; Dubey, M. K.

    2011-12-01

    Currently, absorbing aerosols are thought to be the most uncertain factor in atmospheric climate models (~0.4-1.2 W/m2), and the 2nd most important factor after CO2 in global warming (1.6 W/m2; Ramanathan and Carmichael, Nature Geoscience, 2008; Myhre, Science, 2009). While most well-recognized atmospheric aerosols, e.g., sulfate from power-plants, have a cooling effect on the atmosphere by scattering solar radiation, black carbon (BC or soot) absorbs sunlight strongly which results in a warming of the atmosphere. Dust particles are also present globally and can absorb radiation, contributing to a warmer and drier atmosphere. Direct on-line measurements of BC and hematite, an absorbing dust aerosol, can be made with the Single Particle Soot Photometer (SP2), which measures the mass of the particles by incandescence on an individual particle basis. Measurements from the SP2 are combined with absorption measurements from the three-wavelength photoacoustic soot spectrometer (PASS-3) at 405, 532, and 781 nm and the ultraviolet photoacoustic soot spectrometer (PASS-UV) at 375 nm to determine wavelength-dependent mass absorption coefficients (MACs). Laboratory aerosol samples include flame-generated soot, fullerene soot, Aquadag, hematite, and hematite-containing dusts. Measured BC MAC's compare well with published values, and hematite MAC's are an order of magnitude less than BC. Absorbing aerosols measured in the laboratory are compared with those from ambient aerosols measured during the Las Conchas fire and BEACHON-RoMBAS. The Las Conchas fire was a wildfire in the Jemez Mountains of New Mexico that burned over 100,000 acres during the Summer of 2011, and BEACHON-RoMBAS (Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H2O, Organics & Nitrogen - Rocky Mountain Biogenic Aerosol Study) is a field campaign focusing on biogenic aerosols at the Manitou Forest Observatory near Colorado Springs, CO in Summer 2011. Optical properties and size

  1. COMPARATIVE STUDY OF GLUCOMETER AND LABORATORY GLUCOSE OXIDASE METHOD FOR THE ESTIMATION OF BLOOD GLUCOSE LEVELS IN NEONATES

    Directory of Open Access Journals (Sweden)

    Harish

    2015-02-01

    Full Text Available INTRODUCTION : Hypoglycemia is one of the most common metabolic problems encountered in neonates. Hypoglycemia in neonates can be symptomatic and asymptomatic. Hypoglycemia is known to be associated with brain dysfunction and neuromotor developmental retardation. The gl ucose oxidase method used in the laboratory for determining the blood glucose concentration is precise and specific for glucose. As it is usually performed in the main laboratory, the results are not available quickly enough for timely appropriate manageme nt. The glucometers are often used for blood glucose estimation in NICU. Many studies have shown that their results co - relate well with the laboratory measured glucose levels in the normoglycemic and hyperglycemic range but are not satisfactory in the lowe r range. OBJECTIVES: This is a prospective study done to determine the efficacy of glucometer in estimation of blood glucose levels in neonates in comparison with the laboratory values. METHOD S : 250 neonates admitted in NICU, KIMS hospital, Bangalore with varied symptomatology were enrolled in this study. Blood glucose estimation was done by glucometer and laboratory method using the same venous sample at the time of admission. For the last 50 cases glucometer estimation of capillary blood was also done. St atistical analysis was done by using Pearson correlation. Hypoglycemia was defined as blood glucose level 45mg%[0.756] and when the value is <45mg%, there is just a moderate correlation[0.417] . Though the pick - up rate of hypoglycemia by venous blood glucometer [28%] was slightly better compared to the capillary blood glucometer value [22%] , the overa ll pick - up rate of hypoglycemia by glucometer is very low compared to the laboratory method [56%]. CONCLUSION : The glucometer as a sole measuring device to screen neonatal hypoglycemia is not satisfactory and confirmation with the laboratory measurements o f plasma glucose is still of up most importance.

  2. Tsunami damping by mangrove forest: a laboratory study using parameterized trees

    Directory of Open Access Journals (Sweden)

    A. Strusińska-Correia

    2013-02-01

    Full Text Available Tsunami attenuation by coastal vegetation was examined under laboratory conditions for mature mangroves Rhizophora sp. The developed novel tree parameterization concept, accounting for both bio-mechanical and structural tree properties, allowed to substitute the complex tree structure by a simplified tree model of identical hydraulic resistance. The most representative parameterized mangrove model was selected among the tested models with different frontal area and root density, based on hydraulic test results. The selected parameterized tree models were arranged in a forest model of different width and further tested systematically under varying incident tsunami conditions (solitary waves and tsunami bores. The damping performance of the forest models under these two flow regimes was compared in terms of wave height and force envelopes, wave transmission coefficient as well as drag and inertia coefficients. Unlike the previous studies, the results indicate a significant contribution of the foreshore topography to solitary wave energy reduction through wave breaking in comparison to that attributed to the forest itself. A similar rate of tsunami transmission (ca. 20% was achieved for both flow conditions (solitary waves and tsunami bores and the widest forest (75 m in prototype investigated. Drag coefficient CD attributed to the solitary waves tends to be constant (CD = 1.5 over the investigated range of the Reynolds number.

  3. Laboratory study of magnetic reconnection with a density asymmetry across the current sheet.

    Science.gov (United States)

    Yoo, Jongsoo; Yamada, Masaaki; Ji, Hantao; Jara-Almonte, Jonathan; Myers, Clayton E; Chen, Li-Jen

    2014-08-29

    The effects of a density asymmetry across the current sheet on anti-parallel magnetic reconnection are studied systematically in a laboratory plasma. Despite a significant density ratio of up to 10, the in-plane magnetic field profile is not significantly changed. On the other hand, the out-of-plane Hall magnetic field profile is considerably modified; it is almost bipolar in structure with the density asymmetry, as compared to quadrupolar in structure with the symmetric configuration. Moreover, the ion stagnation point is shifted to the low-density side, and the electrostatic potential profile also becomes asymmetric with a deeper potential well on the low-density side. Nonclassical bulk electron heating together with electromagnetic fluctuations in the lower hybrid frequency range is observed near the low-density-side separatrix. The dependence of the ion outflow and reconnection electric field on the density asymmetry is measured and compared with theoretical expectations. The measured ion outflow speeds are about 40% of the theoretical values.

  4. GEOPHYSICAL AND LABORATORY STUDIES OF THE SPREAD AND QUALITY OF THE ODUKPANI LIMESTONE DEPOSIT

    Directory of Open Access Journals (Sweden)

    A. E. Akpan

    2014-01-01

    Full Text Available The Odukpani limestone deposit has been investigated using geophysical and laboratory techniques with the aim of generating information on its spread and quality. Information generated from the analyses of twenty-six Vertical Electrical Soundings (VES and core drilling data were used in the study. The VES data were acquired in both grid and random patterns in the immediate area of the limestone mineralisation and the adjoining areas using the Schlumberger array was adopted in acquiring the VES data in both grid and random patterns in the limestone mineralized and the adjoining areas. Cored limestone samples were analysed using the Proton Induced X-ray Emission (PIXE method in order to determine their elemental composition and consequently quality. Both manual and computer modeling techniques were used in modeling the VES. Results show that the limestones have limited spread and have high concentration of Ca ((11,200% and K (302,400%. Mean electrical resistivity of the limestone horizon is 405 Ωm which is suggestive of a limestone deposit that is not pure but contaminated with Fe (8,620%, shaly and other contaminants. The limestone deposit is limited in both vertical and lateral extents. Thus the deposit will not favor any large scale mining operation and equipment deployed for its exploitation must be corrosion resistant type.

  5. A laboratory experimental setup for photo-absorption studies using synchrotron radiation

    CERN Document Server

    Shastri, A; Saraswati, P; Sunanda, K

    2002-01-01

    The photophysics beamline, which is being installed at the 450 MeV Synchrotron Radiation Source (SRS), Indus-l, is a medium resolution beamline useful for a variety of experiments in the VUV region viz. 500-2000 A. One of the major applications of this beamline is gas-phase photo-absorption studies. An experimental set up to be used for these experiments was designed, developed and tested in our laboratory. The setup consists of a high vacuum absorption cell, 1/4 m monochromator and detection system. For the purpose of testing, xenon and tungsten continuum sources were used and absorption spectra were recorded in the UV region. This setup was used to record the absorption spectrum of a few molecules like acetone, ammonia, benzene, formaldehyde and acetaldehyde in order to evaluate the performance of the experimental system which will subsequently be used with the photophysics beamline. Details of the design, fabrication and testing of the absorption cell and experimental procedures are presented in this repor...

  6. Laboratory Studies of the Role of Amines in Particle Formation, Growth and Climate

    Energy Technology Data Exchange (ETDEWEB)

    Finlayson-Pitts, Barbara J. [Univ. of California, Irvine, CA (United States)

    2015-02-07

    Organosulfur compounds have a variety of sources, particularly biological processes in the oceans. Their oxidation in air forms sulfur dioxide, which is further oxidized to sulfuric acid, as well as methanesulfonic acid (MSA). While sulfuric acid is a well known precursor to particles in air, MSA had not been regarded as a source of new particle formation. Laboratory studies were carried out under this project that showed MSA forms new particles quite efficiently in the presence of amines and water vapor. The data could be reproduced with a relatively simple kinetics model representing cluster formation and growth, which is promising for representing this chemistry in global climate models. The initial steps in the kinetics scheme are based on quantum chemical calculations of likely clusters. The organosulfur chemistry was introduced into an atmospheric model for southern California and used to predict the impact of going to a fossil-fuel free world in which anthropogenic emissions of SO2 are removed, but the natural processes remain.

  7. Complex refractive indices of Saharan dust samples at visible and near UV wavelengths: a laboratory study

    Directory of Open Access Journals (Sweden)

    R. Wagner

    2011-07-01

    Full Text Available We have retrieved the wavelength-dependent imaginary parts of the complex refractive index for five different Saharan dust aerosol particles of variable mineralogical composition at wavelengths between 305 and 955 nm. The dust particles were generated by re-dispersing soil samples into a laboratory aerosol chamber, typically yielding particle sizes with mean diameters ranging from 0.3 to 0.4 μm and maximum diameters from 2 to 4 μm. The extinction and absorption coefficients as well as the number size distribution of the dust particles were simultaneously measured by various established techniques. An inversion scheme based on a spheroidal dust model was employed to deduce the refractive indices. The retrieved imaginary parts of the complex refractive index were in the range from 0.003 to 0.005, 0.005 to 0.011, and 0.016 to 0.050 at the wavelengths 955, 505, and 305 nm. The hematite content of the dust particles was determined by electron-microscopical single particle analysis. Hematite volume fractions in the range from 1.1 to 2.7 % were found for the different dusts, a range typical for atmospheric mineral dust. We have performed a sensitivity study to assess how accurately the retrieved imaginary refractive indices could be reproduced by calculations with mixing rule approximations using the experimentally determined hematite contents as input.

  8. Laboratory study on the ecological impact of sophorolipid used for harmful algae elimination

    Science.gov (United States)

    Sun, Xiaoxia; Kim, Eunki; Sun, Song

    2010-11-01

    We studied the role of sophorolipid in inhibiting harmful algae bloom (HAB). Different sophorolipid concentrations were tested on marine microalgae, zooplankton, fish, and bivalve ( Mytilus edulis) in laboratory. The result shows that sophorolipid could inhibit the growth of algal species selectively. Among three algae species selected, Platymonas helgolandica var. tsingtaoensis was promoted with increasing sophorolipid concentration; Isochrysis galbana was inhibited seven days later in sophorolipid concentration below 40 mg/L; and Nitzschia closterium f. minutissima was inhibited obviously in only a high sophorolipid concentration over 20 mg/L. Therefore, sophorolipid in a low concentration at Artemia salina was 600 mg/L. The relative clearance rate of mussel Mytilus edulis decreased to 80%, 40%, and 20% of the control group after being exposed to 20, 50, and 100 mg/L sophorolipid for 24 h. Therefore, the toxicity for mitigation of harmful algae bloom at previously recommended concentration of 5-20 mg/L sophorolipid is low for most tested organisms in this reaserch.

  9. Biodegradation of petroleum sludge and petroleum polluted soil by a bacterial consortium: a laboratory study.

    Science.gov (United States)

    Gojgic-Cvijovic, G D; Milic, J S; Solevic, T M; Beskoski, V P; Ilic, M V; Djokic, L S; Narancic, T M; Vrvic, M M

    2012-02-01

    This article presents a study of the efficiency and degradation pattern of samples of petroleum sludge and polluted sandy soil from an oil refinery. A bacterial consortium, consisting of strains from the genera Pseudomonas, Achromobacter, Bacillus and Micromonospora, was isolated from a petroleum sludge sample and characterized. The addition of nitrogen and phosphorus nutrients and a chemical surfactant to both the samples and bioaugmentation to the soil sample were applied under laboratory conditions. The extent of biodegradation was monitored by the gravimetric method and analysis of the residual oil by gas chromatography. Over a 12-week experiment, the achieved degree of TPH (total petroleum hydrocarbon) degradation amounted to 82-88% in the petroleum sludge and 86-91% in the polluted soil. Gas chromatography-mass spectrometry was utilized to determine the biodegradability and degradation rates of n-alkanes, isoprenoids, steranes, diasteranes and terpanes. Complete degradation of the n-alkanes and isoprenoids fractions occurred in both the samples. In addition, the intensities of the peaks corresponding to tricyclic terpenes and homohopanes were decreased, while significant changes were also observed in the distribution of diasteranes and steranes.

  10. Mineralization of nitrogen from pelletized sewage sludge - a laboratory incubation study

    Energy Technology Data Exchange (ETDEWEB)

    Wattiez, Anne-Laure

    2000-07-01

    Nitrogen limits the productivity of most ecosystems, but can also cause environmental problems. With the increasing amount of sludge generated by better wastewater treatment, land application of pelletized sludge appears as a combined solution to waste disposal and plant nitrogen nutrition issues. Six types of sludge pellets/granules, containing different mixtures of sludge, ash and/or lime have been inoculated and incubated for 8 weeks at 20 deg C in the dark, to study N net mineralisation rates. Laboratory results showed no indication of general differences between sludge/ash and sludge/lime mixtures, with respect to N mineralisation and nitrification, but some differences between Umeaa pellets and GaevIe granules were discernible. The higher net N mineralisation rates in pellets appeared to be related to sludge properties. On the contrary pellets had a low level of nitrification, which might be explained by preliminary heat treatment of the sludge and the seemingly slow recolonization of nitrifiers. It is also believed that considerable amounts of N were lost, and that the major route for these losses was ammonia volatilisation. From an economical point of view, sludge pelletisation appears to be the most cost-effective means of disposal. It transforms sludge into a valuable, odourless and storable fertiliser or heat source. Some income could even be expected. The benefits obtained from an increased tree growth could justify forest fertilisation with pelletized sludge, but further research is needed to determine more precisely the possible growth increment and the consequences on the environment.

  11. Difficulties in Laboratory Studies and Astronomical Observations of Organic Molecules: Hydroxyacetone and Lactic Acid

    Science.gov (United States)

    Apponi, A. J.; Brewster, M. A.; Hoy, J.; Ziurys, L. M.

    2006-01-01

    For the past 35 years, radio astronomy has revealed a rich organic chemistry in the interstellar gas, which is exceptionally complex towards active star-forming regions. New solar systems condense out of this gas and may influence the evolution of life on newly formed planets. Much of the biologically important functionality is present among the some 130 gas-phase molecules found to date, including alcohols, aldehydes, ketones, acids, amines, amides and even the simplest sugar - glycolaldehyde. Still, many unidentified interstellar radio signals remain, and their identification relies on further laboratory study. The molecules hydroxyacetone and lactic acid are relatively small organic molecules, but possess rather complex rotational spectra owing to their high asymmetry. Hydroxyacetone is particularly problematic because it possess a very low barrier to internal rotation, and exhibits strong coupling of the free-rotor states with the overall rotation of the molecule. As in the case of acetamide, a full decomposition method was employed to order the resultant eigenstates onto normal asymmetric top eigenvectors.

  12. Exposure setups for laboratory animals and volunteer studies using body-mounted antennas.

    Science.gov (United States)

    Bahr, Achim; Adami, C; Bolz, T; Rennings, A; Dorn, H; Rüttiger, L

    2007-01-01

    For two different in vivo exposure setups body-mounted antenna systems have been designed. The first setup is designed for investigation of volunteers during simulated mobile phone usage. The setup consists of a dual-band antenna for GSM/WCDMA with enhanced carrying properties, which enables exposure for at least 8 h a day. The 10 g averaged localised SAR--normalised to an antenna input power of 1 W--measured in the flat phantom area of the SAM phantom amounts to 7.82 mW g(-1) (900 MHz) and 10.98 mW g(-1) (1966 MHz). The second exposure setup is used for a laboratory behavioural study on rats. The design goal was a localised, well-defined SAR distribution inside the animals' heads at 900 MHz. To fulfil the biological requirements, a loop antenna was developed. For tissues around the ears, a localised SAR value of 50.12 W kg(-1) averaged over a mass of 2.2 g for an antenna input power of 1 W is obtained.

  13. Laboratory studies of magnetized collisionless flows and shocks using accelerated plasmoids

    Science.gov (United States)

    Weber, T. E.; Smith, R. J.; Hsu, S. C.

    2015-11-01

    Magnetized collisionless shocks are thought to play a dominant role in the overall partition of energy throughout the universe, but have historically proven difficult to create in the laboratory. The Magnetized Shock Experiment (MSX) at LANL creates conditions similar to those found in both space and astrophysical shocks by accelerating hot (100s of eV during translation) dense (1022 - 1023 m-3) Field Reversed Configuration (FRC) plasmoids to high velocities (100s of km/s); resulting in β ~ 1, collisionless plasma flows with sonic and Alfvén Mach numbers of ~10. The FRC subsequently impacts a static target such as a strong parallel or anti-parallel (reconnection-wise) magnetic mirror, a solid obstacle, or neutral gas cloud to create shocks with characteristic length and time scales that are both large enough to observe yet small enough to fit within the experiment. This enables study of the complex interplay of kinetic and fluid processes that mediate cosmic shocks and can generate non-thermal distributions, produce density and magnetic field enhancements much greater than predicted by fluid theory, and accelerate particles. An overview of the experimental capabilities of MSX will be presented, including diagnostics, selected recent results, and future directions. Supported by the DOE Office of Fusion Energy Sciences under contract DE-AC52-06NA25369.

  14. Laboratory study on factors influencing nitrogen removal in marble chip biofilters incorporating nitritation and anammox.

    Science.gov (United States)

    Tao, Wendong; Wen, Jianfeng; Norton, Christopher

    2011-01-01

    It remains challenging to integrate nitritation and anammox in ecologically engineered treatment systems such as passive biofilters that are packed with natural materials and have low energy inputs. This study explored the factors influencing nitritation-anammox through parallel operation of two laboratory-scale biofilters packed with large and small marble chips respectively. Clean marble chips (mainly CaCO3) had an alkalinity dissolution rate of 130 mg CaCO3/kg marble d when water pH approached 6.5. Marble chips effectively increased water pH and provided sufficient alkalinity to support nitritation-anammox in the biofilters. Ammonium and total nitrogen removal decreased by 47 and 26%, respectively, when nutrients were not amended to influent. An influent nitrite concentration above 8.9 mg N/L could inhibit anammox in thin biofilms of biofilters. Nitritation-anammox was enhanced with a hydraulic retention time of 2 d relative to 7 d, likely due to enhanced air entrainment. Size of marble chips rarely made a significant difference in nitrogen removal, possibly due to sufficient surface area available for bacterial attachment and alkalinity dissolution.

  15. High-throughput sorting of mosquito larvae for laboratory studies and for future vector control interventions

    Directory of Open Access Journals (Sweden)

    Marois Eric

    2012-08-01

    Full Text Available Abstract Background Mosquito transgenesis offers new promises for the genetic control of vector-borne infectious diseases such as malaria and dengue fever. Genetic control strategies require the release of large number of male mosquitoes into field populations, whether they are based on the use of sterile males (sterile insect technique, SIT or on introducing genetic traits conferring refractoriness to disease transmission (population replacement. However, the current absence of high-throughput techniques for sorting different mosquito populations impairs the application of these control measures. Methods A method was developed to generate large mosquito populations of the desired sex and genotype. This method combines flow cytometry and the use of Anopheles gambiae transgenic lines that differentially express fluorescent markers in males and females. Results Fluorescence-assisted sorting allowed single-step isolation of homozygous transgenic mosquitoes from a mixed population. This method was also used to select wild-type males only with high efficiency and accuracy, a highly desirable tool for genetic control strategies where the release of transgenic individuals may be problematic. Importantly, sorted males showed normal mating ability compared to their unsorted brothers. Conclusions The developed method will greatly facilitate both laboratory studies of mosquito vectorial capacity requiring high-throughput approaches and future field interventions in the fight against infectious disease vectors.

  16. Studies on nutritional status in general surgery patients by clinical, anthropometric, and laboratory parameters.

    Science.gov (United States)

    Butters, M; Straub, M; Kraft, K; Bittner, R

    1996-06-01

    We assessed the nutritional status of general surgery patients with and without cancer from a western European population in this prospective study. Anamnestic (weight development, abdominal complaints) and anthropometric (fat tissue measurements) data were collected on six groups of patients: cancer of the stomach (n = 13), pancreas (n = 13), colorectal (n = 23), breast (n = 12), and two control groups with benign diseases, ages 20-45 and 50-75 y. From these data, body mass index and ideal body weight were calculated. Concentrations of albumin, transferrin, retinol-binding protein, prealbumin, and creatinine height index were determined by biochemical tests. A weight loss of more than 10% was found in only 31% of gastric and 61% of pancreatic cancer patients. Significant values from anthropometric data were also found only in these groups. In biochemical tests, only the creatinine height index was reduced in all patients with pancreatic cancer. The remaining laboratory changes were so unspecific in all other parameters that no conclusions could be drawn as to the status of the patient's nutritional condition. For the evaluation of nutritional status, only relatively simple and inexpensive anamnestic and anthropometric measurements are necessary.

  17. Feasibility Study of a Laser Beat-Wave Seeded THz FEL at the Neptune Laboratory

    CERN Document Server

    Reiche, Sven; Pellegrini, Claudio; Rosenzweig, James E; Shvets, Gennady; Tochitsky, Sergei Ya

    2005-01-01

    Free-Electron Laser in the THz range can be used to generate high output power radiation or to modulate the electron beam longitudinally on the radiation wavelength scale. Microbunching on the scale of 1-5 THz is of particular importance for potential phase-locking of a modulated electron beam to a laser-driven plasma accelerating structure. However the lack of a seeding source for the FEL at this spectral range limits operation to a SASE FEL only, which denies a subpicosecond synchronization of the current modulation or radiation with an external laser source. One possibility to overcome this problem is to seed the FEL with two external laser beams, which difference (beat-wave) frequency is matched to the resonant FEL frequency in the THz range. In this presentation we study feasibility of an experiment on laser beat-wave injection in the THz FEL considered at the UCLA Neptune Laboratory, where both a high brightness photoinjector and a two-wavelength, TW-class CO2 laser system exist. By incorporating the en...

  18. Accretion shocks in the laboratory: Design of an experiment to study star formation

    Science.gov (United States)

    Young, R. P.; Kuranz, C. C.; Drake, R. P.; Hartigan, P.

    2017-06-01

    We present the design of a laboratory-astrophysics experiment to study magnetospheric accretion relevant to young, pre-main-sequence stars. Spectra of young stars show evidence of hotspots created when streams of accreting material impact the surface of the star and create shocks. The structures that form during this process are poorly understood, as the surfaces of young stars cannot be spatially resolved. Our experiment would create a scaled ;accretion shock; at a major (several kJ) laser facility. The experiment drives a plasma jet (the ;accretion stream;) into a solid block (the ;stellar surface;), in the presence of a parallel magnetic field analogous to the star's local field. We show that this experiment is well-scaled when the incoming jet has ρ ∼10-6 -10-5gcm-3 and u ∼ 100 - 200kms-1 in an imposed field of B ∼ 10 T. Such an experiment would represent an average accretion stream onto a pre-main sequence star with B ∼ 700 G.

  19. Are fish fed with cyanobacteria safe, nutritious and delicious? A laboratory study

    Science.gov (United States)

    Liang, Hualei; Zhou, Wenshan; Zhang, Yulei; Qiao, Qin; Zhang, Xuezhen

    2015-10-01

    Toxic cyanobacterial blooms, which produce cyclic heptapeptide toxins known as microcystins, are worldwide environmental problems. On the other hand, the cyanobacteria protein (30-50%) has been recommended as substitute protein for aquaculture. The present laboratory study verified the feasibility of cyanobacteria protein substitution and risk assessment. Goldfish were fed diets supplemented lyophilised cyanobacteria powder for 16 weeks with the various doses: 0% (control), 10%, 20%, 30% and 40%. Low doses (10% and 20%) promoted growth whereas high doses (30% and 40%) inhibited growth. In cyanobacteria treated fish, the proximate composition of ash, crude fat content and crude protein content decreased in 16 weeks; the saturated fatty acid (SFA) content significantly increased; the n-3 polyunsaturated fatty acid content, collagen content and muscle pH significantly decreased; cooking loss percents increased significantly. Muscle fiber diameter and myofibril length were negatively correlation. Additionally, flavour compounds (e.g., amino acids, nucleotides, organic acids and carnosine) changed significantly in the treated fish, and odour compounds geosmin and 2-methylisoborneol increased significantly. The estimated daily intake (EDI) of microcystins in muscle was close to or exceeded the World Health Organization (WHO) tolerable daily intake (TDI), representing a great health risk. Cyanobacterie is not feasible for protein sources use in aquaculture.

  20. Laboratory and field studies related to the Hydrology/Radionuclide Migration Project

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, J.L. (comp.)

    1991-05-01

    This annual report describes research conducted in FY 1990 by Los Alamos National Laboratory for the Hydrology/Radionuclide Migration Project. This multi-agency project measures the underground movement of radionuclides related to nuclear testing at the Nevada Test Site. This project continues the long-term experiment at the site of the Cambric nuclear test. Water pumped from a well adjacent to the explosion cavity continues to show decreasing amounts of tritium and Krypton 85 but no Cesium 139. Analyses of drillback debris shows a distinction between refractory and volatile materials in respect to both their location in the test cavity and their leachability with groundwater. We surveyed materials used during nuclear testing to evaluate any post-test hazard; we concluded that most such materials pose a minimal hazard. The Los Alamos drilling program provided an opportunity for us to sample a collapsed zone above the cavity of a test, which was fired 2 years ago. We continue our research in colloid characterization and in detection of low levels of Technetium 99 in Nevada Test Site water. During FY 1990, we drilled a new hole in the Yucca Flat area to study radionuclide migration. This report also describes Los Alamos management and planning activities in support of this project. 20 refs., 2 figs., 14 tabs.

  1. Using Virtual Laboratories as Interactive Textbooks: Studies on Blended Learning in Biotechnology Classrooms

    Directory of Open Access Journals (Sweden)

    Hemalatha Sasidharakurup

    2015-07-01

    Full Text Available Virtual laboratories, an ICT-based initiative, is a new venture that is becoming more prevalent in universities for improving classroom education. With geographically remote and economically constrained institutes in India as the focus, we developed web-based virtual labs for virtualizing the wet-lab techniques and experiments with the aid of graphics favoured animations, mathematical simulators and remote triggered experimentations. In this paper, we analysed perceived usefulness of Biotechnology virtual labs amongst student groups and its role in improving the student’s performance when introduced as a learning tool in a blended classroom scenario. A pedagogical survey, via workshops and online feedback, was carried out among 600 university-level students and 100 remote users of various Indian universities. Comparing learning groups on usage of blended learning approach against a control group (traditional classroom methods and an experimental group (teacher-mediated virtual labs, our studies indicate augmented academic performance among students in blended environments. Findings also indicated usage of remotely-triggered labs aided enhancing interaction-based lab education enabling anytime-anywhere student participation scenarios.

  2. A laboratorial study on influence of alkaline and oxidative environment on preservation of Pinus tabulaeformis pollen

    Institute of Scientific and Technical Information of China (English)

    Fang TIAN; Xianyong CAO; Qinghai XU; Yuecong LI

    2009-01-01

    Different sedimentary settings can influence preservation of pollens, which would lead to mis-interpretation of fossil pollen spectrum. This study investigates the influence on the preservation of Pinus tabulaeformis pollen by simulating alkaline and oxidative environment in the laboratory. There was no obvious change in the content ofPinus tabulaeformis pollen while comparing the original with the ones that were immersed with 10% NaOH liquor for ten days, or boiled for five hours, and or boiled with 20%-30% NaOH for one hour,respectively. However, the pollen fossils were obviously corroded and eroded after being boiled with 40% NaOH for one hour and were seriously corroded after five hours. The result indicates that Pinus tabulaeformis pollen is quite durable in alkaline environment and heating condition within a shorter period of time, although alkaline environment has a disadvantage for its preservation. We also tested the influence of oxidation on Pinus tabulae-formis pollen preservation with KMnO4 as oxidant. The result presents that the number of remaining Pinus tabulaeformis pollen grains decreased quickly after being dipped in KMnO4 along with extending the reaction time and reinforcing oxidant. The rate of remnant pollen grains was less than 1% after being dipped with 2% KMnO4 for one hour. It is suggested that oxidative environment has stronger influence on Pinus tabulaeformis pollen preserva tion than alkaline environment.

  3. Oxidation and waste-to-energy output of aluminium waste packaging during incineration: A laboratory study.

    Science.gov (United States)

    López, Félix A; Román, Carlos Pérez; García-Díaz, Irene; Alguacil, Francisco J

    2015-09-01

    This work reports the oxidation behaviour and waste-to-energy output of different semi-rigid and flexible aluminium packagings when incinerated at 850°C in an air atmosphere enriched with 6% oxygen, in the laboratory setting. The physical properties of the different packagings were determined, including their metallic aluminium contents. The ash contents of their combustion products were determined according to standard BS ISO 1171:2010. The net calorific value, the required energy, and the calorific gain associated with each packaging type were determined following standard BS EN 13431:2004. Packagings with an aluminium lamina thickness of >50μm did not fully oxidise. During incineration, the weight-for-weight waste-to-energy output of the packagings with thick aluminium lamina was lower than that of packagings with thin lamina. The calorific gain depended on the degree of oxidation of the metallic aluminium, but was greater than zero for all the packagings studied. Waste aluminium may therefore be said to act as an energy source in municipal solid waste incineration systems. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Precise Laboratory Measurement of Line Frequencies Useful to Studies of Star and Planet Formation

    Science.gov (United States)

    Myers, Philip C.; Gottlieb, Carl A.

    2005-01-01

    In March 2002, we began a program in laboratory spectroscopy to provide accurate molecular line frequencies essential to studies of the motions and abundance in star-forming dense cores and planet-forming circumstellar disks. Summarized here is the progress that has been made in Year 3 of this grant. Work included measurement of 10 successive rotational lines in the ground vibrational state of SiO between 86 and 500 GHz, and two lines near 800 GHz to an accuracy of a few kHz; conducting pilot experiments on molecular ions in collision-free supersonic beams, including HCO+, N2H+, and H2D+; measurement of 22 lines of CN between 113 and 340 GHz; and setting up an experiment that would allow us to refine earlier measurements of the neutral species such as C3H2, CCS, H2CS, and SO by observing the very narrow sub-Doppler (Lamb dip) features in the millimeter-wave spectra of these species.

  5. Laboratory measurements of materials in extreme conditions; The use of high energy radiation sources for high pressure studies

    Energy Technology Data Exchange (ETDEWEB)

    Cauble, R.; Remington, B.A.

    1998-06-01

    High energy lasers can be used to study material conditions that are appropriate fort inertial confinement fusion: that is, materials at high densities, temperatures, and pressures. Pulsed power devices can offer similar opportunities. The National Ignition Facility (NIF) will be a high energy multi-beam laser designed to achieve the thermonuclear ignition of a mm-scale DT-filled target in the laboratory. At the same time, NE will provide the physics community with a unique tool for the study of high energy density matter at states unreachable by any other laboratory technique. Here we describe how these lasers and pulsed power tools can contribute to investigations of high energy density matter in the areas of material properties and equations of state, extend present laboratory shock techniques such as high-speed jets to new regimes, and allow study of extreme conditions found in astrophysical phenomena.

  6. Study of energy conversion and partitioning in the magnetic reconnection layer of a laboratory plasma

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, Masaaki; Yoo, Jongsoo; Jara-Almonte, Jonathan; Ji, Hantao; Kulsrud, Russell M.; Myers, Clayton E. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Daughton, William [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2015-05-15

    While the most important feature of magnetic reconnection is that it energizes plasma particles by converting magnetic energy to particle energy, the exact mechanisms by which this happens are yet to be determined despite a long history of reconnection research. Recently, we have reported our results on the energy conversion and partitioning in a laboratory reconnection layer in a short communication [Yamada et al., Nat. Commun. 5, 4474 (2014)]. The present paper is a detailed elaboration of this report together with an additional dataset with different boundary sizes. Our experimental study of the reconnection layer is carried out in the two-fluid physics regime where ions and electrons move quite differently. We have observed that the conversion of magnetic energy occurs across a region significantly larger than the narrow electron diffusion region. A saddle shaped electrostatic potential profile exists in the reconnection plane, and ions are accelerated by the resulting electric field at the separatrices. These accelerated ions are then thermalized by re-magnetization in the downstream region. A quantitative inventory of the converted energy is presented in a reconnection layer with a well-defined, variable boundary. We have also carried out a systematic study of the effects of boundary conditions on the energy inventory. This study concludes that about 50% of the inflowing magnetic energy is converted to particle energy, 2/3 of which is ultimately transferred to ions and 1/3 to electrons. Assisted by another set of magnetic reconnection experiment data and numerical simulations with different sizes of monitoring box, it is also observed that the observed features of energy conversion and partitioning do not depend on the size of monitoring boundary across the range of sizes tested from 1.5 to 4 ion skin depths.

  7. Laboratory Studies for Planetary Sciences. A Planetary Decadal Survey White Paper Prepared by the American Astronomical Society (AAS) Working Group on Laboratory Astrophysics (WGLA)

    CERN Document Server

    Gudipati, The AAS WGLA: Murthy; Brickhouse, Nancy; Cowan, John; Drake, Paul; Federman, Steven; Ferland, Gary; Frank, Adam; Haxton, Wick; Herbst, Eric; Mumma, Michael; Salama, Farid; Savin, Daniel Wolf; Ziurys, Lucy

    2009-01-01

    The WGLA of the AAS (http://www.aas.org/labastro/) promotes collaboration and exchange of knowledge between astronomy and planetary sciences and the laboratory sciences (physics, chemistry, and biology). Laboratory data needs of ongoing and next generation planetary science missions are carefully evaluated and recommended in this white paper submitted by the WGLA to Planetary Decadal Survey.

  8. Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume Studies

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, Paul T. [Electric Power Research Institute; Amaral, Stephen V. [Alden Research Laboratory; Castro-Santos, Theodore [U.S. Geological Survey; Giza, Dan [Alden Research Laboratory; Haro, Alexander J. [U.S. Geological Survey; Hecker, George [Alden Research Laboratory; McMahon, Brian [Alden Research Laboratory; Perkins, Norman [Alden Research Laboratory; Pioppi, Nick [Alden Research Laboratory

    2012-12-31

    This collection of three reports describes desktop and laboratory flume studies that provide information to support assessment of the potential for injury and mortality of fish that encounter hydrokinetic turbines of various designs installed in tidal and river environments. Behavioral responses to turbine exposure also are investigated to support assessment of the potential for disruptions to upstream and downstream movements of fish. The studies: (1) conducted an assessment of potential injury mechanisms using available data from studies with conventional hydro turbines; (2) developed theoretical models for predicting blade strike probabilities and mortality rates; and (3) performed flume testing with three turbine designs and several fish species and size groups in two laboratory flumes to estimate survival rates and document fish behavior. The project yielded three reports which this document comprises. The three constituent documents are addressed individually below Fish Passage Through Turbines: Application of Conventional Hydropower Data to Hydrokinetic Technologies Fish passing through the blade sweep of a hydrokinetic turbine experience a much less harsh physical environment than do fish entrained through conventional hydro turbines. The design and operation of conventional turbines results in high flow velocities, abrupt changes in flow direction, relatively high runner rotational and blade speeds, rapid and significant changes in pressure, and the need for various structures throughout the turbine passageway that can be impacted by fish. These conditions generally do not occur or are not significant factors for hydrokinetic turbines. Furthermore, compared to conventional hydro turbines, hydrokinetic turbines typically produce relatively minor changes in shear, turbulence, and pressure levels from ambient conditions in the surrounding environment. Injuries and mortality from mechanical injuries will be less as well, mainly due to low rotational speeds and

  9. Case studies identify savings of up to $40,000 for academic research laboratories with the use of video journals

    Science.gov (United States)

    Pritsker, Moshe

    2015-04-01

    Recent studies indicate that 70% to 90% of results published in science journals are not reproducible, which presents troubling uncertainty about the future of scientific research. In contrast to the text format of traditional journals, novel video-based journals allow for systematic, step-by-step visualized demonstrations of research experiments. Video articles produce a more efficient transfer of knowledge between laboratories and therefore offer a viable solution to the issue of reproducibility. To quantify the savings of time and money generated by this alternative mode of scientific communication, we conducted a number of case studies among academic laboratories who use the peer-reviewed video journal JoVE. One study determined that using video as a guide to learn a new dissection technique saved a bioengineering lab at the University of Washington 40,000. A second case study found that a laboratory at Cornell University studying muscular dystrophy eliminated 6 months of experimentation by learning a new complex stem cell injection technique from the video journal. Results from a third study indicated that a laboratory at the University of Helsinki shortened the time to learn a surgical technique from 1 year to 2 weeks. Together, these studies indicate that video publication significantly enhances the reproducibility and productivity of scientific research.

  10. Recommendations for the design of laboratory studies on non-target arthropods for risk assessment of genetically engineered plants.

    Science.gov (United States)

    Romeis, Jörg; Hellmich, Richard L; Candolfi, Marco P; Carstens, Keri; De Schrijver, Adinda; Gatehouse, Angharad M R; Herman, Rod A; Huesing, Joseph E; McLean, Morven A; Raybould, Alan; Shelton, Anthony M; Waggoner, Annabel

    2011-02-01

    This paper provides recommendations on experimental design for early-tier laboratory studies used in risk assessments to evaluate potential adverse impacts of arthropod-resistant genetically engineered (GE) plants on non-target arthropods (NTAs). While we rely heavily on the currently used proteins from Bacillus thuringiensis (Bt) in this discussion, the concepts apply to other arthropod-active proteins. A risk may exist if the newly acquired trait of the GE plant has adverse effects on NTAs when they are exposed to the arthropod-active protein. Typically, the risk assessment follows a tiered approach that starts with laboratory studies under worst-case exposure conditions; such studies have a high ability to detect adverse effects on non-target species. Clear guidance on how such data are produced in laboratory studies assists the product developers and risk assessors. The studies should be reproducible and test clearly defined risk hypotheses. These properties contribute to the robustness of, and confidence in, environmental risk assessments for GE plants. Data from NTA studies, collected during the analysis phase of an environmental risk assessment, are critical to the outcome of the assessment and ultimately the decision taken by regulatory authorities on the release of a GE plant. Confidence in the results of early-tier laboratory studies is a precondition for the acceptance of data across regulatory jurisdictions and should encourage agencies to share useful information and thus avoid redundant testing.

  11. Comparative biological potency of acidic sulfate aerosols: implications for the interpretation of laboratory and field studies.

    Science.gov (United States)

    Schlesinger, R B; Chen, L C

    1994-04-01

    Biological responses to inhaled acid sulfates result from the deposition of hydrogen ion (H+) on airway surfaces. Thus, effects from sulfuric acid and ammonium bisulfate, the two major ambient species, have been assumed to be the same for a given H+ concentration within the exposure atmosphere, assuming similar respiratory tract deposition patterns. However, recent inhalation studies have indicated that sulfuric acid is disproportionately potent compared to ammonium bisulfate when the H+ content of the exposure atmosphere is considered, suggesting that some factors following inhalation affect the amount of H+ contacting airway surfaces. This study assessed a mechanism potentially underlying this phenomenon, namely, the extent of neutralization by respiratory tract ammonia. This was evaluated using a physical model system designed to mimic transit of these aerosols in the upper respiratory tract of the animal model used in this laboratory, the rabbit. The results suggest that for equal exposure quantities of H+, more acid would be deposited when sulfuric acid is inhaled than when ammonium bisulfate is inhaled. Furthermore, results from a series of in vitro exposures of tracheal epithelial cells to sulfuric acid and ammonium bisulfate aerosols indicated that the biological response is a function of the total mass (ionic) concentration of H+ deliverable to the cells or the total extractable H+ per particle. The results of this study have possible implications for ambient monitoring of particulate-associated strong acidity, suggesting that it may be necessary to specilate such measures into the relative amounts of H+ as sulfuric acid or ammonium bisulfate in order to most accurately relate atmospheric acid levels to observed health effects. In addition, since much of the ambient particulate-associated H+ exists as sulfuric acid/ammonium bisulfate mixtures rather than pure compounds, H(+)-associated health effects from controlled exposure studies of sulfuric acid may

  12. A STUDY OF LABORATORY PROFILE OF NEONATAL SEPSIS AT NICU (SNCU, WARANGAL

    Directory of Open Access Journals (Sweden)

    Sudhakar

    2016-05-01

    Full Text Available BACKGROUND Of the 130 million babies born worldwide each year, 26 million are born in India alone. Four million babies die with in first 30 days of birth and another four million are stillborn. Newborn mortality represents 40% of all deaths of children less than five years of age. Of the four million deaths each year, nearly 98% occur in developing countries. Globally major causes of neonatal deaths are due to preterm births (28%, sepsis or pneumonia (26% and birth asphyxia (23%. Neonatal sepsis is one of the commonest causes of neonatal deaths in the developing world accounting to 30-50% of all neonatal deaths per year. The present study is intended to help the practising paediatrician to accurately diagnose the sepsis early using the specific laboratory tests and avert the progression of the disease. METHODS It is an observational cross-sectional study in NICU, Mahatma Gandhi Memorial Hospital. The study was conducted in the period November 2013 to October 2014. After admission, detailed history and thorough clinical examination was done. Required data was entered in a pre-set proforma and statistical analysis was done. Blood culture was sent. Bacterial culture and sensitivity was checked. RESULTS In proven sepsis, 50.25% were Gram-positive, 43.65% were Gram-negative and 6.09% were fungal sepsis Candida. Klebsiella (32.48% was the most common organism followed by Coagulase positive Staphylococcus (25.38% and CONS (20.81%. In this study, Gram-negative sepsis was more common in preterm and Gram-positive sepsis was more common in term neonates. Early onset sepsis was the common presentation of proven sepsis, Klebsiella was common organism causing EOS. Whereas CONS was commonest causing late onset sepsis. Among Gram-negative organisms, 58.1% and 27.9% were resistant to cefotaxime and ampicillin+sulbactam respectively. Among Gram-positive isolates, 35% and 22% were resistant to cefotaxime and ampicillin+sulbactam respectively. Klebsiella, most

  13. Laboratory studies of immersion and deposition mode ice nucleation of ozone aged mineral dust particles

    Directory of Open Access Journals (Sweden)

    Z. A. Kanji

    2013-09-01

    Full Text Available Ice nucleation in the atmosphere is central to the understanding the microphysical properties of mixed-phase and cirrus clouds. Ambient conditions such as temperature (T and relative humidity (RH, as well as aerosol properties such as chemical composition and mixing state play an important role in predicting ice formation in the troposphere. Previous field studies have reported the absence of sulfate and organic compounds on mineral dust ice crystal residuals sampled at mountain top stations or aircraft based measurements despite the long-range transport mineral dust is subjected to. We present laboratory studies of ice nucleation for immersion and deposition mode on ozone aged mineral dust particles for 233 T ns are reported and observed to increase as a function of decreasing temperature. We present first results that demonstrate enhancement of the ice nucleation ability of aged mineral dust particles in both the deposition and immersion mode due to ageing. We also present the first results to show a suppression of heterogeneous ice nucleation activity without the condensation of a coating of (inorganic material. In immersion mode, low ozone exposed Ka particles showed enhanced ice activity requiring a median freezing temperature of 1.5 K warmer than that of untreated Ka, whereas high ozone exposed ATD particles showed suppressed ice nucleation requiring a median freezing temperature of 3 K colder than that of untreated ATD. In deposition mode, low exposure Ka had ice active fractions of an order of magnitude higher than untreated Ka, whereas high ozone exposed ATD had ice active fractions up to a factor of 4 lower than untreated ATD. From our results, we derive and present parameterizations in terms of ns(T that can be used in models to predict ice nuclei concentrations based on available aerosol surface area.

  14. Laboratory studies of immersion and deposition mode ice nucleation of ozone aged mineral dust particles

    Directory of Open Access Journals (Sweden)

    Z. A. Kanji

    2013-04-01

    Full Text Available Ice nucleation in the atmosphere is central to the understanding the microphysical properties of mixed-phase and cirrus clouds. Ambient conditions such as temperature (T and relative humidity (RH, as well as aerosol properties such as chemical composition and mixing state play an important role in predicting ice formation in the troposphere. Previous field studies have reported the absence of sulphate and organic compounds on mineral dust ice crystal residuals sampled at mountain top stations or aircraft based measurements despite the long range transport mineral dust is subjected to. We present laboratory studies of ice nucleation for immersion and deposition mode on ozone aged mineral dust particles for 233 T ns are reported and observed to increase as a function of temperature. We present first results that demonstrate enhancement of the ice nucleation ability of aged mineral dust particles in both the deposition and immersion mode due to ageing. Additionally, these are also the first results to show a suppression of heterogeneous ice nucleation without the condensation of a coating of (inorganic material. In immersion mode, low exposure Ka particles showed enhanced ice activity requiring a median freezing temperature of 1.5 K warmer than that of untreated Ka whereas high exposure ATD particles showed suppressed ice nucleation requiring a median freezing temperature of 3 K colder than that of untreated ATD. In deposition mode, low exposure Ka had ice active fractions of an order of magnitude higher than untreated Ka, where as high exposure ATD had ice active fractions up to a factor of 4 lower than untreated ATD. Based on our results, we present parameterizations in terms of ns(T that can represent ice nucleation of atmospherically aged and non-aged particles for both immersion and deposition mode. We find excellent agreement (to within less than a factor of 2 with field measurements when parameterizations derived from our results are used to

  15. Novel miniature mobile cardiac catheterization laboratory for critical cardiovascular disease following natural disasters: a feasibility study

    Institute of Scientific and Technical Information of China (English)

    HAN Ya-ling; MENG Wei-hong; LIANG Zhuo; YAO Tian-ming; SUN Jing-yang; LIANG Ming; HUO Yu; WANG Geng; WANG Xiao-zeng; LIANG Yan-chun

    2012-01-01

    Background Natural disasters have been frequent in recent years.Effective treatment of patients with cardiovascular disease following natural disasters is an unsolved problem.We aimed to develop a novel miniature mobile cardiac catheterization laboratory (Mini Mobile Cath Lab) to provide emergency interventional services for patients with critical cardiovascular disease following natural disasters.A feasibility study was performed by testing the Mini Mobile Cath Lab on dogs with ST-elevation myocardial infarction (STEMI) model in a hypothetical natural-disaster-stricken area.Methods The Mini Mobile Cath Lab was transported to the hypothetical natural-disaster-stricken area by truck.Coronary angiography and primary percutaneous coronary intervention (PCI) were performed on six dogs with STEMI model.The transportation and transformation of the Mini Mobile Cath Lab were monitored and its functioning was evaluated through the results of animal experiments.Results The Mini Mobile Cath Lab could be transpdrted by truck at an average speed of 80 km/h on mountain roads during daytime in the winter,under conditions of light snow (-15℃ to -20℃/-68°F to -59°F).The average time required to prepare the Mini Mobile Cath Lab after transportation,in a wetland area,was 30 minutes.Coronary angiography,and primary PCI were performed successfully.Conclusion This preliminary feasibility study of the use of the Mini Mobile Cath Lab for emergency interventional treatment of dogs with STEMI indicated that it may perform well in the rescue of critical cardiovascular disease following natural disasters.

  16. A Laboratory Study of Natural Zeolite for Treatment of Fluorinated Water

    Science.gov (United States)

    Pandey, A.

    2015-12-01

    Fluoride contamination is mainly induced in ground water by chemical interaction between water and fluoride bearing rocks and natural fluoridation is further catalyzed by anthropogenic activities. Elevated fluoride concentrations in the water bodies above the permissible limits are not only degrading water for drinking purposes but also to the agricultural, industrial as well as daily household needs. Fluoride content in water has been constantly a subject of serious concern to the concerned authorities. It is significantly contributing in increasing tolls of arthritis, brain and kidney diseases, cancer, male fertility issues and cases of thyroid diseases. Hence, the present study has been conducted to investigate the possibility of treating fluorinated water using zeolites. The capabilities of natural zeolites are attributed to their catalytic, molecular sieve, adsorption and ion-exchange properties which have been utilized in our laboratory experiment. The experiment was carried out in two phases. In the first phase of the experiment, the properties of zeolites were tested in solid and liquid phases using ICP-OES, SEM, EDX and IC tests. Physio-chemical alterations induced by zeolites in the fluid chemistry were monitored by analyzing fluid sample regularly for pH, redox potential, electrical conductivity and total dissolved solids, and by conducting metal and anion tests. In second phase, zeolite was used for treatment of fluorinated water with known concentration of fluoride, and the geochemical processes associated with fluoride remediation were monitored by conducting non-invasive, invasive geochemical and physical measurements at regular time periods on the water samples collected from both control column and the experiment column. Results thus obtained in this study showed decrease in fluoride concentration over time, indicating the possibility of use of zeolites in treatment of fluorinated water.

  17. Numerical study of wave effects on groundwater flow and solute transport in a laboratory beach

    Science.gov (United States)

    Geng, Xiaolong; Boufadel, Michel C.; Xia, Yuqiang; Li, Hailong; Zhao, Lin; Jackson, Nancy L.; Miller, Richard S.

    2014-09-01

    A numerical study was undertaken to investigate the effects of waves on groundwater flow and associated inland-released solute transport based on tracer experiments in a laboratory beach. The MARUN model was used to simulate the density-dependent groundwater flow and subsurface solute transport in the saturated and unsaturated regions of the beach subjected to waves. The Computational Fluid Dynamics (CFD) software, Fluent, was used to simulate waves, which were the seaward boundary condition for MARUN. A no-wave case was also simulated for comparison. Simulation results matched the observed water table and concentration at numerous locations. The results revealed that waves generated seawater-groundwater circulations in the swash and surf zones of the beach, which induced a large seawater-groundwater exchange across the beach face. In comparison to the no-wave case, waves significantly increased the residence time and spreading of inland-applied solutes in the beach. Waves also altered solute pathways and shifted the solute discharge zone further seaward. Residence Time Maps (RTM) revealed that the wave-induced residence time of the inland-applied solutes was largest near the solute exit zone to the sea. Sensitivity analyses suggested that the change in the permeability in the beach altered solute transport properties in a nonlinear way. Due to the slow movement of solutes in the unsaturated zone, the mass of the solute in the unsaturated zone, which reached up to 10% of the total mass in some cases, constituted a continuous slow release of solutes to the saturated zone of the beach. This means of control was not addressed in prior studies.

  18. Laboratory Study on Biological Control of Ticks (Acari: Ixodidae by Entomopathogenic Indigenous Fungi (Beauveria bassiana

    Directory of Open Access Journals (Sweden)

    M Abdigoudarzi

    2009-12-01

    Full Text Available Background: Chemical control method using different acaricides as spray, dipping solution or pour-on is routinely used for controlling ticks. Biological control agents are favorable due to their safety for animals and environment. Entomopathogenic fungi such as Beauveria bassiana are well known for controlling ticks. In this study, two Iranian indigenous strains of B. bassiana (B. bassiana 5197 and B. bassiana Evin were selected and grown on specific me­dia. The pathogenic effects of these strains were evaluated on adult stages of two Iranian Ixodidae members (H. anatolicum anatolicum Koch 1844, and H. marginatum Koch 1844 by dipping method."nMethods: Two Iranian strains of Beauveria bassiana (Beauveria bassiana 5197 and Beauveria bassiana Evin were selected and were grown successfully on specific media. The pathogenic effects of these strains were evaluated on adult stages of Iranian Ixodidae members such as, Hyalomma anatolicum anatolicum and H. marginatum by dipping method (these ticks were grown up at laboratory conditions during 2002 up to 2003 and still it is continued ."nResults: There was no effect of strain 5197 on mortality or fecundity rates for ticks. There was acute phase sign of paralysis in test group after dipping ticks in suspension made from Evin strain of B. bassiana. In addition, the test groups were totally died after four months, but the control groups survived for six months."nConclusion: High concentration of fungal spores is needed for inducing fungal infection. Additional study using different strains and fungi on Iranian ticks is proposed.   Keywords: Biological control, fungi, Beauveria bassiana, ticks, Ixodidae, Iran

  19. Laboratory studies on the vulnerability of young white sturgeon to predation

    Science.gov (United States)

    Gadomski, D.M.; Parsley, M.J.

    2005-01-01

    Despite evidence of annual spawning by white sturgeon Acipenser transmontanus in rivers of the northwestern United States and Canada, in some years and locations little or no recruitment of age-0 white sturgeon has been observed. We examined the vulnerability of white sturgeon larvae and juveniles to predation to further understand possible causes of mortality. We were particularly interested in the vulnerability of older larvae and juveniles because at about 25 mm total length (TL) white sturgeon develop sharp dorsal and lateral scutes that may act as a morphological defense. In the laboratory, white sturgeon ranging from newly hatched larvae to about 170-mm TL juveniles were exposed to predatory fishes they might encounter in the natural environment. We found that channel catfish Ictalurus punctatus (mean TL = 464 mm) and northern pikeminnow Ptychocheilus oregonensis (mean TL = 472 mm) ate white sturgeon up to mean sizes of 121 and 134 mm TL, respectively. Conversely, similarly sized walleyes Sander vitreus ingested almost no white sturgeon, although juvenile walleyes (mean TL = 184 mm) ate white sturgeon up to 59 mm TL. The smallest predator we tested, prickly sculpins Cottus asper (mean TL = 126 mm), ate white sturgeon up to a mean TL of 50 mm. Our study demonstrated that predation is a likely cause of mortality of age-0 white sturgeon and may be contributing to the year-class failures that have been observed. In addition, the results from this study could be used to reduce the predation risk of artificially propagated white sturgeon released to augment declining populations since fish could be reared to sizes where their vulnerability is low.

  20. Study on the thermal deactivation of motorcycle catalytic converters by laboratory aging tests.

    Science.gov (United States)

    Chen, Yi-Chi; Chen, Lu-Yen; Yu, Yi-Hsien; Jeng, Fu-Tien

    2010-03-01

    Catalytic converters are used to curb exhaust pollution from motorcycles in Taiwan. A number of factors, including the length of time the converter is used for and driving conditions, affect the catalysts' properties during periods of use. The goal of this study is to resolve the thermal deactivation mechanism of motorcycle catalytic converters. Fresh catalysts were treated under different aging conditions by laboratory-scale aging tests to simulate the operation conditions of motorcycle catalytic converters. The aged catalysts were characterized by analytical techniques in order to provide information for investigating deactivation phenomena. The time-dependent data of specific surface areas were subsequently used to construct kinetics of sintering at the specific temperature. According to the analytical results of the catalysts' properties, the increase in aging temperature causes an increase in pore size of the catalysts and a decrease in the specific surface area. The aged catalysts all exhibited lower performances than the fresh ones. The reduction in catalytic activity is consistent with the reduction in the loss of specific surface area. The finding of catalytic properties' dependence on temperature is consistent with the thermally activated theory. In contrast, the effect of the aging time on the specific surface area was only significant during the initial few hours. The high correlation between specific surface areas measured by the Brunauer-Emmett-Teller (BET) method and predicted by the constructed model verifies that the prediction models can predict the sintering rate reasonably under the aging conditions discussed in this study. As compared to automobile catalytic converters, the differences of structures and aging conditions are made less obvious by the deactivation phenomena of motorcycles.

  1. Laboratory markers of disease severity in Plasmodium knowlesi infection: a case control study

    Directory of Open Access Journals (Sweden)

    Willmann Matthias

    2012-10-01

    Full Text Available Abstract Background Plasmodium knowlesi malaria causes severe disease in up to 10% of cases in Malaysian Borneo and has a mortality rate of 1 - 2%. However, laboratory markers with the ability to identify patients at risk of developing complications have not yet been assessed as they have for other species of Plasmodium. Methods A case control study was undertaken in two hospitals in Sarikei and Sibu, Malaysian Borneo. One hundred and ten patients with uncomplicated (n = 93 and severe (n = 17 P. knowlesi malaria were studied. Standardized pigment-containing neutrophil (PCN count, parasite density and platelet counts were determined and analysed by logistic regression and receiver operating characteristic (ROC analysis. Results The PCN count was strongly associated with risk of disease severity. Patients with high parasite density (≥ 35,000/μl or with thrombocytopaenia (≤ 45,000/μl were also more likely to develop complications (odds ratio (OR = 9.93 and OR = 5.27, respectively. The PCN count yielded the highest area under the ROC curve (AUC estimate among all markers of severity (AUC = 0.8561, 95% confidence interval: 0.7328, 0.9794. However, the difference between all parameter AUC estimates was not statistically significant (Wald test, p = 0.73. Conclusion Counting PCN is labour-intensive and not superior in predicting severity over parasitaemia and platelet counts. Parasite and platelet counts are simpler tests with an acceptable degree of precision. Any adult patient diagnosed with P. knowlesi malaria and having a parasite count ≥35,000/μl or ≥1% or a platelet count ≤45,000/μl can be regarded at risk of developing complications and should be managed according to current WHO guidelines for the treatment of severe malaria.

  2. Performance of brain MRI of a two generation father-and-son family with long-term smoking caffeinum natrio benzoicum

    Institute of Scientific and Technical Information of China (English)

    SUN Wan-li; ZHANG Li-fang; LIU Hong; ZHAO Li-yun; XING Yu-ping; YUAN Ning

    2010-01-01

    @@ Since the 1970s, some people in north, northeast,northwest areas began to smoke caffeinum natrio benzoicum (CNB) and started to abuse CNB. As a common ingredient that can be found in drugs or drinks,many studies on the safety of CNB have been investigated, but no one has shown significant abnormality in the brain of a CNB abuser by using neuroimaging. In our study, three subjects from of a two generation father-and-son family with long-term smoking CNB were enrolled. Combining with the clinical data and taking the cocaine animal trial model and toxicology as the reference, we wanted to observe the performance of brain MRI and MRS of patients with long-term smoking CNB.

  3. Environmental Effects of Hydrokinetic Turbines on Fish: Desktop and Laboratory Flume Studies

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, Paul T. [Electric Power Research Institute; Amaral, Stephen V. [Alden Research Laboratory; Castro-Santos, Theodore [U.S. Geological Survey; Giza, Dan [Alden Research Laboratory; Haro, Alexander J. [U.S. Geological Survey; Hecker, George [Alden Research Laboratory; McMahon, Brian [Alden Research Laboratory; Perkins, Norman [Alden Research Laboratory; Pioppi, Nick [Alden Research Laboratory

    2012-12-31

    This collection of three reports describes desktop and laboratory flume studies that provide information to support assessment of the potential for injury and mortality of fish that encounter hydrokinetic turbines of various designs installed in tidal and river environments. Behavioral responses to turbine exposure also are investigated to support assessment of the potential for disruptions to upstream and downstream movements of fish. The studies: (1) conducted an assessment of potential injury mechanisms using available data from studies with conventional hydro turbines; (2) developed theoretical models for predicting blade strike probabilities and mortality rates; and (3) performed flume testing with three turbine designs and several fish species and size groups in two laboratory flumes to estimate survival rates and document fish behavior. The project yielded three reports which this document comprises. The three constituent documents are addressed individually below Fish Passage Through Turbines: Application of Conventional Hydropower Data to Hydrokinetic Technologies Fish passing through the blade sweep of a hydrokinetic turbine experience a much less harsh physical environment than do fish entrained through conventional hydro turbines. The design and operation of conventional turbines results in high flow velocities, abrupt changes in flow direction, relatively high runner rotational and blade speeds, rapid and significant changes in pressure, and the need for various structures throughout the turbine passageway that can be impacted by fish. These conditions generally do not occur or are not significant factors for hydrokinetic turbines. Furthermore, compared to conventional hydro turbines, hydrokinetic turbines typically produce relatively minor changes in shear, turbulence, and pressure levels from ambient conditions in the surrounding environment. Injuries and mortality from mechanical injuries will be less as well, mainly due to low rotational speeds and

  4. Toward a quality guide to facilitate the transference of analytical methods from research to testing laboratories: a case study.

    Science.gov (United States)

    Bisetty, Krisnha; Gumede, Njabulo Joyfull; Escuder-Gilabert, Laura; Sagrado, Salvador

    2009-01-01

    At present, there is no single viewpoint that defines QA strategies in analytical chemistry. On the other hand, there are no unique protocols defining a set of analytical tasks and decision criteria to be performed during the method development phase (e.g., by a single research laboratory) in order to facilitate the transference to the testing laboratories intending to adapt, validate, and routinely use this method. This study proposes general criteria, a priori valid for any developed method, recommended as a provisional quality guide containing the minimum internal tasks necessary to publish new analytical method results. As an application, the selection of some basic internal quality tasks and the corresponding accepted criteria are adapted to a concrete case study: indirect differential pulse polarographic determination of nitrate in water samples according to European Commission requisites. Extra tasks to be performed by testing laboratories are also outlined.

  5. A focused ethnographic study of Sri Lankan government field veterinarians' decision making about diagnostic laboratory submissions and perceptions of surveillance.

    Directory of Open Access Journals (Sweden)

    Kate Sawford

    Full Text Available The global public health community is facing the challenge of emerging infectious diseases. Historically, the majority of these diseases have arisen from animal populations at lower latitudes where many nations experience marked resource constraints. In order to minimize the impact of future events, surveillance of animal populations will need to enable prompt event detection and response. Many surveillance systems targeting animals rely on veterinarians to submit cases to a diagnostic laboratory or input clinical case data. Therefore understanding veterinarians' decision-making process that guides laboratory case submission and their perceptions of infectious disease surveillance is foundational to interpreting disease patterns reported by laboratories and engaging veterinarians in surveillance initiatives. A focused ethnographic study was conducted with twelve field veterinary surgeons that participated in a mobile phone-based surveillance pilot project in Sri Lanka. Each participant agreed to an individual in-depth interview that was recorded and later transcribed to enable thematic analysis of the interview content. Results found that field veterinarians in Sri Lanka infrequently submit cases to laboratories--so infrequently that common case selection principles could not be described. Field veterinarians in Sri Lanka have a diagnostic process that operates independently of laboratories. Participants indicated a willingness to take part in surveillance initiatives, though they highlighted a need for incentives that satisfy a range of motivations that vary among field veterinarians. This study has implications for the future of animal health surveillance, including interpretation of disease patterns reported, system design and implementation, and engagement of data providers.

  6. A focused ethnographic study of Sri Lankan government field veterinarians' decision making about diagnostic laboratory submissions and perceptions of surveillance.

    Science.gov (United States)

    Sawford, Kate; Vollman, Ardene Robinson; Stephen, Craig

    2012-01-01

    The global public health community is facing the challenge of emerging infectious diseases. Historically, the majority of these diseases have arisen from animal populations at lower latitudes where many nations experience marked resource constraints. In order to minimize the impact of future events, surveillance of animal populations will need to enable prompt event detection and response. Many surveillance systems targeting animals rely on veterinarians to submit cases to a diagnostic laboratory or input clinical case data. Therefore understanding veterinarians' decision-making process that guides laboratory case submission and their perceptions of infectious disease surveillance is foundational to interpreting disease patterns reported by laboratories and engaging veterinarians in surveillance initiatives. A focused ethnographic study was conducted with twelve field veterinary surgeons that participated in a mobile phone-based surveillance pilot project in Sri Lanka. Each participant agreed to an individual in-depth interview that was recorded and later transcribed to enable thematic analysis of the interview content. Results found that field veterinarians in Sri Lanka infrequently submit cases to laboratories--so infrequently that common case selection principles could not be described. Field veterinarians in Sri Lanka have a diagnostic process that operates independently of laboratories. Participants indicated a willingness to take part in surveillance initiatives, though they highlighted a need for incentives that satisfy a range of motivations that vary among field veterinarians. This study has implications for the future of animal health surveillance, including interpretation of disease patterns reported, system design and implementation, and engagement of data providers.

  7. A Focused Ethnographic Study of Sri Lankan Government Field Veterinarians’ Decision Making about Diagnostic Laboratory Submissions and Perceptions of Surveillance

    Science.gov (United States)

    Sawford, Kate; Vollman, Ardene Robinson; Stephen, Craig

    2012-01-01

    The global public health community is facing the challenge of emerging infectious diseases. Historically, the majority of these diseases have arisen from animal populations at lower latitudes where many nations experience marked resource constraints. In order to minimize the impact of future events, surveillance of animal populations will need to enable prompt event detection and response. Many surveillance systems targeting animals rely on veterinarians to submit cases to a diagnostic laboratory or input clinical case data. Therefore understanding veterinarians’ decision-making process that guides laboratory case submission and their perceptions of infectious disease surveillance is foundational to interpreting disease patterns reported by laboratories and engaging veterinarians in surveillance initiatives. A focused ethnographic study was conducted with twelve field veterinary surgeons that participated in a mobile phone-based surveillance pilot project in Sri Lanka. Each participant agreed to an individual in-depth interview that was recorded and later transcribed to enable thematic analysis of the interview content. Results found that field veterinarians in Sri Lanka infrequently submit cases to laboratories – so infrequently that common case selection principles could not be described. Field veterinarians in Sri Lanka have a diagnostic process that operates independently of laboratories. Participants indicated a willingness to take part in surveillance initiatives, though they highlighted a need for incentives that satisfy a range of motivations that vary among field veterinarians. This study has implications for the future of animal health surveillance, including interpretation of disease patterns reported, system design and implementation, and engagement of data providers. PMID:23133542

  8. The laboratories of geological studies; Les laboratoires d`etudes geologiques

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-01-01

    This educational document comprises 4 booklets in a folder devoted to the presentation of the ANDRA`s activities in geological research laboratories. The first booklet gives a presentation of the missions of the ANDRA (the French agency for the management of radioactive wastes) in the management of long life radioactive wastes. The second booklet describes the approach of waste disposal facilities implantation. The third booklet gives a brief presentation of the scientific program concerning the underground geologic laboratories. The last booklet is a compilation of questions and answers about long-life radioactive wastes, the research and works carried out in geologic laboratories, the public information and the local socio-economic impact, and the storage of radioactive wastes in deep geological formations. (J.S.)

  9. Degradation studies of fenazaquin in soil under field and laboratory conditions.

    Science.gov (United States)

    Duhan, Anil; Kumari, Beena

    2011-08-01

    Degradation of fenazaquin in sandy loam soil was investigated under field and laboratory conditions. Fenazaquin (Magister 10EC) was applied @ 125 and 250 g a.i./ha in field and in pot under field capacity moisture in laboratory. Samples drawn periodically were analyzed on GC-NPD. The residues of fenazaquin in both the doses and conditions dissipated almost 90% in 90 days. Half-life period were 32.04 and 31.35 days at two doses, respectively at field conditions and 30.10 and 28.94 days at laboratory conditions. Dissipation was approximated to first order kinetics in both conditions having correlation coefficient ranging from -0.9848 to -0.9914.

  10. Study and survey of assembling parameters to a radioactive source production laboratory used to verify equipment

    Energy Technology Data Exchange (ETDEWEB)

    Gauglitz, Erica; Nagatomy, Helio Rissei; Moura, Eduardo S.; Zeituni, Carlos Alberto; Hilario, Katia A. Fonseca; Rostelato, Maria Elisa C.M., E-mail: egauglitz@ipen.b, E-mail: elisaros@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Karam Junior, Dib, E-mail: dib.karan@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Escola de Artes, Ciencias e Humanidades

    2009-07-01

    This paper presents the survey of parameters for the installation and implementation of a laboratory for radioactive sources production at immobilized resin. These sources are used in nuclear medicine for verification of dose calibrators, as the standard guidelines of the National Commission of Nuclear CNEN-NE-3.05 'Radioprotection and safety requirements for nuclear medicine services.' The radioisotopes used for this purpose are: Co-57, Cs-137 and Ba-133, with activities of 185 MBq, 9.3 MBq and 5.4 MBq, respectively. The parameters for the assembly of the laboratory shall be defined according to guidelines that guide the deployment of radiochemical laboratories and standards of the National Commission of Nuclear Energy. (author)

  11. Biogas production from cheese whey wastewater: laboratory- and full-scale studies.

    Science.gov (United States)

    Stamatelatou, K; Giantsiou, N; Diamantis, V; Alexandridis, C; Alexandridis, A; Aivasidis, A

    2014-01-01

    A two-phase system for biogas production from cheese whey wastewater (CWW) was designed, set up and operated at laboratory and full scale for a whole cheese production season (8-9 months). The high efficiency and stability of the laboratory-scale system was demonstrated under various organic loading rates (OLRs) reaching 13 g chemical oxygen demand (COD) L(-1)d(-1) and producing up to 9 L L(-1)d(-1) of biogas (approximately 55% in methane). The COD removal was above 95% and the pH was maintained above 6.3 without any chemical addition. The full-scale system was operated at lower OLRs than its normal capacity, following the good response and high stability in disturbances of the laboratory-scale unit.

  12. Laboratory study of acid stimulation of drilling-mud-damaged geothermal-reservoir materials. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1983-05-01

    Presented here are the results of laboratory testing performed to provide site specific information in support of geothermal reservoir acidizing programs. The testing program included laboratory tests performed to determine the effectiveness of acid treatments in restoring permeability of geologic materials infiltrated with hydrothermally altered sepiolite drilling mud. Additionally, autoclave tests were performed to determine the degree of hydrothermal alteration and effects of acid digestion on drilling muds and drill cuttings from two KGRA's. Four laboratory scale permeability/acidizing tests were conducted on specimens prepared from drill cuttings taken from two geothermal formations. Two tests were performed on material from the East Mesa KGRA Well No. 78-30, from a depth of approximately 5500 feet, and two tests were performed on material from the Roosevelt KGRA Well No. 52-21, from depths of approximately 7000 to 7500 feet. Tests were performed at simulated in situ geothermal conditions of temperature and pressure.

  13. A focused ethnographic study of Alberta cattle veterinarians' decision making about diagnostic laboratory submissions and perceptions of surveillance programs.

    Directory of Open Access Journals (Sweden)

    Kate Sawford

    Full Text Available The animal and public health communities need to address the challenge posed by zoonotic emerging infectious diseases. To minimize the impacts of future events, animal disease surveillance will need to enable prompt event detection and response. Diagnostic laboratory-based surveillance systems targeting domestic animals depend in large part on private veterinarians to submit samples from cases to a laboratory. In contexts where pre-diagnostic laboratory surveillance systems have been implemented, this group of veterinarians is often asked to input data. This scenario holds true in Alberta where private cattle veterinarians have been asked to participate in the Alberta Veterinary Surveillance Network-Veterinary Practice Surveillance, a platform to which pre-diagnostic disease and non-disease case data are submitted. Consequently, understanding the factors that influence these veterinarians to submit cases to a laboratory and the complex of factors that affect their participation in surveillance programs is foundational to interpreting disease patterns reported by laboratories and engaging veterinarians in surveillance. A focused ethnographic study was conducted with ten cattle veterinarians in Alberta. Individual in-depth interviews with participants were recorded and transcribed to enable thematic analysis. Laboratory submissions were biased toward outbreaks of unknown cause, cases with unusual mortality rates, and issues with potential herd-level implications. Decreasing cattle value and government support for laboratory testing have contributed to fewer submissions over time. Participants were willing participants in surveillance, though government support and collaboration were necessary. Changes in the beef industry and veterinary profession, as well as cattle producers themselves, present both challenges and opportunities in surveillance.

  14. A focused ethnographic study of Alberta cattle veterinarians' decision making about diagnostic laboratory submissions and perceptions of surveillance programs.

    Science.gov (United States)

    Sawford, Kate; Vollman, Ardene Robinson; Stephen, Craig

    2013-01-01

    The animal and public health communities need to address the challenge posed by zoonotic emerging infectious diseases. To minimize the impacts of future events, animal disease surveillance will need to enable prompt event detection and response. Diagnostic laboratory-based surveillance systems targeting domestic animals depend in large part on private veterinarians to submit samples from cases to a laboratory. In contexts where pre-diagnostic laboratory surveillance systems have been implemented, this group of veterinarians is often asked to input data. This scenario holds true in Alberta where private cattle veterinarians have been asked to participate in the Alberta Veterinary Surveillance Network-Veterinary Practice Surveillance, a platform to which pre-diagnostic disease and non-disease case data are submitted. Consequently, understanding the factors that influence these veterinarians to submit cases to a laboratory and the complex of factors that affect their participation in surveillance programs is foundational to interpreting disease patterns reported by laboratories and engaging veterinarians in surveillance. A focused ethnographic study was conducted with ten cattle veterinarians in Alberta. Individual in-depth interviews with participants were recorded and transcribed to enable thematic analysis. Laboratory submissions were biased toward outbreaks of unknown cause, cases with unusual mortality rates, and issues with potential herd-level implications. Decreasing cattle value and government support for laboratory testing have contributed to fewer submissions over time. Participants were willing participants in surveillance, though government support and collaboration were necessary. Changes in the beef industry and veterinary profession, as well as cattle producers themselves, present both challenges and opportunities in surveillance.

  15. A Focused Ethnographic Study of Alberta Cattle Veterinarians’ Decision Making about Diagnostic Laboratory Submissions and Perceptions of Surveillance Programs

    Science.gov (United States)

    Sawford, Kate; Vollman, Ardene Robinson; Stephen, Craig

    2013-01-01

    The animal and public health communities need to address the challenge posed by zoonotic emerging infectious diseases. To minimize the impacts of future events, animal disease surveillance will need to enable prompt event detection and response. Diagnostic laboratory-based surveillance systems targeting domestic animals depend in large part on private veterinarians to submit samples from cases to a laboratory. In contexts where pre-diagnostic laboratory surveillance systems have been implemented, this group of veterinarians is often asked to input data. This scenario holds true in Alberta where private cattle veterinarians have been asked to participate in the Alberta Veterinary Surveillance Network-Veterinary Practice Surveillance, a platform to which pre-diagnostic disease and non-disease case data are submitted. Consequently, understanding the factors that influence these veterinarians to submit cases to a laboratory and the complex of factors that affect their participation in surveillance programs is foundational to interpreting disease patterns reported by laboratories and engaging veterinarians in surveillance. A focused ethnographic study was conducted with ten cattle veterinarians in Alberta. Individual in-depth interviews with participants were recorded and transcribed to enable thematic analysis. Laboratory submissions were biased toward outbreaks of unknown cause, cases with unusual mortality rates, and issues with potential herd-level implications. Decreasing cattle value and government support for laboratory testing have contributed to fewer submissions over time. Participants were willing participants in surveillance, though government support and collaboration were necessary. Changes in the beef industry and veterinary profession, as well as cattle producers themselves, present both challenges and opportunities in surveillance. PMID:23741397

  16. Chemical aging of m-xylene secondary organic aerosol: laboratory chamber study

    Directory of Open Access Journals (Sweden)

    J. H. Seinfeld

    2012-01-01

    Full Text Available Secondary organic aerosol (SOA can reside in the atmosphere for a week or more. While its initial formation from the gas-phase oxidation of volatile organic compounds tends to take place in the first few hours after emission, SOA can continue to evolve chemically over its atmospheric lifetime. Simulating this chemical aging over an extended time in the laboratory has proven to be challenging. We present here a procedure for studying SOA aging in laboratory chambers that is applied to achieve 36 h of oxidation. The formation and evolution of SOA from the photooxidation of m-xylene under low-NOx conditions and in the presence of either neutral or acidic seed particles is studied. In SOA aging, increasing molecular functionalization leads to less volatile products and an increase in SOA mass, whereas gas- or particle-phase fragmentation chemistry results in more volatile products and a loss of SOA. The challenge is to discern from measured chamber variables the extent to which these processes are important for a given SOA system. In the experiments conducted, m-xylene SOA mass, calculated under the assumption of size-invariant particle composition, increased over the initial 12–13 h of photooxidation and decreased beyond that time, suggesting the existence of fragmentation chemistry. The oxidation of the SOA, as manifested in the O:C elemental ratio and fraction of organic ion detected at m/z 44 measured by the Aerodyne aerosol mass spectrometer, increased continuously starting after 5 h of irradiation until the 36 h termination. This behavior is consistent with an initial period in which, as the mass of SOA increases, products of higher volatility partition to the aerosol phase, followed by an aging period in which gas- and particle-phase reaction products become increasingly more oxidized. When irradiation is stopped 12.4 h into one experiment, and OH generation ceases, minimal loss of SOA is observed, indicating that the loss of SOA is either

  17. Effects of aging on organic aerosol from open biomass burning smoke in aircraft and laboratory studies

    Directory of Open Access Journals (Sweden)

    M. J. Cubison

    2011-12-01

    Full Text Available Biomass burning (BB is a large source of primary and secondary organic aerosols (POA and SOA. This study addresses the physical and chemical evolution of BB organic aerosols. Firstly, the evolution and lifetime of BB POA and SOA signatures observed with the Aerodyne Aerosol Mass Spectrometer are investigated, focusing on measurements at high-latitudes acquired during the 2008 NASA ARCTAS mission, in comparison to data from other field studies and from laboratory aging experiments. The parameter f60, the ratio of the integrated signal at m/z 60 to the total signal in the organic component mass spectrum, is used as a marker to study the rate of oxidation and fate of the BB POA. A background level of f60~0.3% ± 0.06% for SOA-dominated ambient OA is shown to be an appropriate background level for this tracer. Using also f44 as a tracer for SOA and aged POA and a surrogate of organic O:C, a novel graphical method is presented to characterise the aging of BB plumes. Similar trends of decreasing f60 and increasing f44 with aging are observed in most field and lab studies. At least some very aged BB plumes retain a clear f60 signature. A statistically significant difference in f60 between highly-oxygenated OA of BB and non-BB origin is observed using this tracer, consistent with a substantial contribution of BBOA to the springtime Arctic aerosol burden in 2008. Secondly, a summary is presented of results on the net enhancement of OA with aging of BB plumes, which shows large variability. The estimates of net OA gain range from ΔOA/ΔCO(mass = −0.01 to ~0.05, with a mean ΔOA/POA ~19%. With these ratios and global inventories of BB CO and POA a global net OA source due to aging of BB plumes of ~8 ± 7 Tg OA yr−1 is estimated, of the order of 5 % of recent total OA source estimates. Further field data

  18. Effect of adrenergic agonists on coronary blood flow: a laboratory study in healthy volunteers.

    Science.gov (United States)

    Vargas Pelaez, Alvaro F; Gao, Zhaohui; Ahmad, Tariq A; Leuenberger, Urs A; Proctor, David N; Maman, Stephan R; Muller, Matthew D

    2016-05-01

    Myocardial oxygen supply and demand mismatch is fundamental to the pathophysiology of ischemia and infarction. The sympathetic nervous system, through α-adrenergic receptors and β-adrenergic receptors, influences both myocardial oxygen supply and demand. In animal models, mechanistic studies have established that adrenergic receptors contribute to coronary vascular tone. The purpose of this laboratory study was to noninvasively quantify coronary responses to adrenergic receptor stimulation in humans. Fourteen healthy volunteers (11 men and 3 women) performed isometric handgrip exercise to fatigue followed by intravenous infusion of isoproterenol. A subset of individuals also received infusions of phenylephrine (n = 6), terbutaline (n = 10), and epinephrine (n = 4); all dosages were based on fat-free mass and were infused slowly to achieve steady-state. The left anterior descending coronary artery was visualized using Doppler echocardiography. Beat-by-beat heart rate (HR), blood pressure (BP), peak diastolic coronary velocity (CBVpeak), and coronary velocity time integral were calculated. Data are presented as M ± SD Isometric handgrip elicited significant increases in BP, HR, and CBVpeak (from 23.3 ± 5.3 to 34.5 ± 9.9 cm/sec). Isoproterenol raised HR and CBVpeak (from 22.6 ± 4.8 to 43.9 ± 12.4 cm/sec). Terbutaline and epinephrine evoked coronary hyperemia whereas phenylephrine did not significantly alter CBVpeak. Different indices of coronary hyperemia (changes in CBVpeak and velocity time integral) were significantly correlated (R = 0.803). The current data indicate that coronary hyperemia occurs in healthy humans in response to isometric handgrip exercise and low-dose, steady-state infusions of isoproterenol, terbutaline, and epinephrine. The contribution of β1 versus β2 receptors to coronary hyperemia remains to be determined. In this echocardiographic study, we demonstrate that coronary blood flow increases when

  19. A comparative study for radiological decontamination of laboratory fume hood materials.

    Science.gov (United States)

    Thomas, Elizabeth; Sweet, Lucas; MacFarlan, Paul; McNamara, Bruce; Kerschner, Harrison

    2012-08-01

    The efficacy for radiological decontamination of the laboratory standard fume hood as constructed of stainless steel, compared to that of powder-coated carbon steel is described. While the chemical inertness of powder-coated surfaces is good, faced with everyday abrasion, aggressive inorganic solutions and vapors, and penetrating organics commonly employed in government laboratory fume hoods, radiological decontamination of powder-coated steel surfaces was found to be similar to those made of stainless steel for easily solubilized or digestible radionuclides. Plutonium was difficult to remove from stainless steel and powder-coated surfaces, especially after prolonged contact times.

  20. Laboratory measurements and model sensitivity studies of dust deposition ice nucleation

    Directory of Open Access Journals (Sweden)

    G. Kulkarni

    2012-08-01

    Full Text Available We investigated the ice nucleating properties of mineral dust particles to understand the sensitivity of simulated cloud properties to two different representations of contact angle in the Classical Nucleation Theory (CNT. These contact angle representations are based on two sets of laboratory deposition ice nucleation measurements: Arizona Test Dust (ATD particles of 100, 300 and 500 nm sizes were tested at three different temperatures (−25, −30 and −35 °C, and 400 nm ATD and kaolinite dust species were tested at two different temperatures (−30 and −35 °C. These measurements were used to derive the onset relative humidity with respect to ice (RHice required to activate 1% of dust particles as ice nuclei, from which the onset single contact angles were then calculated based on CNT. For the probability density function (PDF representation, parameters of the log-normal contact angle distribution were determined by fitting CNT-predicted activated fraction to the measurements at different RHice. Results show that onset single contact angles vary from ~18 to 24 degrees, while the PDF parameters are sensitive to the measurement conditions (i.e. temperature and dust size. Cloud modeling simulations were performed to understand the sensitivity of cloud properties (i.e. ice number concentration, ice water content, and cloud initiation times to the representation of contact angle and PDF distribution parameters. The model simulations show that cloud properties are sensitive to onset single contact angles and PDF distribution parameters. The comparison of our experimental results with other studies shows that under similar measurement conditions the onset single contact angles are consistent within ±2.0 degrees, while our derived PDF parameters have larger discrepancies.

  1. Transgenic insecticidal crops and natural enemies: a detailed review of laboratory studies.

    Science.gov (United States)

    Lövei, Gabor L; Andow, David A; Arpaia, Salvatore

    2009-04-01

    This review uses a data-driven, quantitative method to summarize the published, peer-reviewed literature about the impact of genetically modified (GM) plants on arthropod natural enemies in laboratory experiments. The method is similar to meta-analysis, and, in contrast to a simple author-vote counting method used by several earlier reviews, gives an objective, data-driven summary of existing knowledge about these effects. Significantly more non-neutral responses were observed than expected at random in 75% of the comparisons of natural enemy groups and response classes. These observations indicate that Cry toxins and proteinase inhibitors often have non-neutral effects on natural enemies. This synthesis identifies a continued bias toward studies on a few predator species, especially the green lacewing, Chrysoperla carnea Stephens, which may be more sensitive to GM insecticidal plants (16.8% of the quantified parameter responses were significantly negative) than predators in general (10.9% significantly negative effects without C. carnea). Parasitoids were more susceptible than predators to the effects of both Cry toxins and proteinase inhibitors, with fewer positive effects (18.0%, significant and nonsignificant positive effects combined) than negative ones (66.1%, significant and nonsignificant negative effects combined). GM plants can have a positive effect on natural enemies (4.8% of responses were significantly positive), although significant negative (21.2%) effects were more common. Although there are data on 48 natural enemy species, the database is still far from adequate to predict the effect of a Bt toxin or proteinase inhibitor on natural enemies.

  2. Laboratory column studies for evaluating a barrier system for providing oxygen and substrate for TCE biodegradation.

    Science.gov (United States)

    Kao, C M; Chen, S C; Su, M C

    2001-08-01

    The industrial solvent trichloroethylene (TCE) is among the most ubiquitous chlorinated compounds found in groundwater contamination. The objective of this study was to develop a biobarrier system containing oxygen-organic releasing material to enhance the aerobic cometabolism of TCE in situ. The oxygen-organic material, which contains calcium peroxide and peat, is able to release oxygen and primary substrates continuously upon contact with water. Batch experiments were conducted to design and identify the components of the oxygen-organic releasing material, and evaluate the oxygen and organic substrate (presented as COD equivalent) release from the designed oxygen-organic material. The observed oxygen and chemical oxygen demand (COD) release rates were approximately 0.0246 and 0.052 mg/d/g of material, respectively. A laboratory-scale column experiment was then conducted to evaluate the feasibility of this proposed system for the bioremediation of TCE-contaminated groundwater. This system was performed using a series of continuous-flow glass columns including a soil column, an oxygen-organic material column, followed by two consecutive soil columns. Aerobic acclimated sludges were inoculated in all three soil columns to provide microbial consortia for TCE biodegradation. Simulated TCE-contaminated groundwater with a flow rate of 0.25 l/day was pumped into this system. Effluent samples from each column were analyzed for TCE and other indicating parameters (e.g., pH, dissolved oxygen). Results show that the decreases in TCE concentrations were observed over a 4-month operating period. Up to 99% of TCE removal efficiency was obtained in this passive system. Results indicate that the continuously released oxygen and organic substrates from the oxygen-organic materials enhanced TCE biotransformation. Thus, the biobarrier treatment scheme has the potential to be developed into an environmentally and economically acceptable remediation technology.

  3. Laboratory measurements and model sensitivity studies of dust deposition ice nucleation

    Directory of Open Access Journals (Sweden)

    G. Kulkarni

    2012-01-01

    Full Text Available We investigated the ice nucleating properties of mineral dust particles to understand the sensitivity of modeled cloud properties to different representations of contact angle in the Classical Nucleation Theory (CNT: onset single angle and probability density function (PDF distribution approaches. These contact angle representations are based on two sets of laboratory deposition ice nucleation measurements: Arizona Test Dust (ATD particles of 100, 300, and 500 nm sizes were tested at three different temperatures (−25, −30 and −35 °C, and 400 nm ATD and Kaolinite dust species were tested at two different temperatures (−30 and −35 °C. These measurements were used to derive the onset relative humidity with respect to ice (RHice required to activate 1% of dust particles as ice nuclei, from which the onset single contact angles were then calculated based on the CNT. For the PDF representation, parameters of the log-normal contact angle distribution (mean and standard deviation were determined by fitting the CNT-predicted activated fraction to the measurements at different RHice. Results show that onset single contact angles are not much different between experiments, while the PDF parameters are sensitive to those environmental conditions (i.e., temperature and dust size. The cloud resolving model simulations show that cloud properties (i.e. ice number concentration, ice water content, and cloud initiation times are sensitive to onset single contact angles and PDF distribution parameters, particularly to the mean value. The comparison of our experimental results with other studies shows that under similar measurement conditions the onset single contact angles are consistent within ±2.0°, while our derived PDF parameters have discrepancies.

  4. Effects of Combined Hands-on Laboratory and Computer Modeling on Student Learning of Gas Laws: A Quasi-Experimental Study

    Science.gov (United States)

    Liu, Xiufeng

    2006-01-01

    Based on current theories of chemistry learning, this study intends to test a hypothesis that computer modeling enhanced hands-on chemistry laboratories are more effective than hands-on laboratories or computer modeling laboratories alone in facilitating high school students' understanding of chemistry concepts. Thirty-three high school chemistry…

  5. A Study of Two Generations of Culturally Diverse Community College Students Views on Leader Attributes in Self and Others

    Science.gov (United States)

    Hodkowski, Paula Jeanine

    2011-01-01

    One community college mission is preparing students for the expectations and opportunities of the workplace including roles as collaborators and leaders. Increasingly, representatives from "cultures" of generation, gender, and diverse ethnicities are gaining an education in community colleges. Research supports that cultural aspects and…

  6. Surveillance of infection severity: a registry study of laboratory diagnosed Clostridium difficile.

    Directory of Open Access Journals (Sweden)

    Iryna Schlackow

    early warning of the changing severity of infectious conditions can be established using routinely collected laboratory hospital data. In the settings studied here these systems have higher performance than those monitoring mortality, at least in C. difficile infection. Such systems could have wider applicability for monitoring infections presenting in hospital.

  7. Laboratory Experiments and Instrument Development for the Study of Atmospheric Aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Davidovits, Paul

    2011-12-10

    Soot particles are generated by incomplete combustion of fossil and biomass fuels. Through direct effects clear air aerosols containing black carbon (BC) such as soot aerosols, absorb incoming light heating the atmosphere, while most other aerosols scatter light and produce cooling. Even though BC represents only 1-2% of the total annual emissions of particulate mass to the atmosphere, it has been estimated that the direct radiative effect of BC is the second-most important contributor to global warming after absorption by CO2. Ongoing studies continue to underscore the climate forcing importance of black carbon. However, estimates of the radiative effects of black carbon on climate remain highly uncertain due to the complexity of particles containing black carbon. Quantitative measurement of BC is challenging because BC often occurs in highly non-spherical soot particles of complex morphology. Freshly emitted soot particles are typically fractal hydrophobic aggregates. The aggregates consist of black carbon spherules with diameters typically in the range of about 15-40 nm, and they are usually coated by adsorbed polyaromatic hydrocarbons (PAHs) produced during combustion. Diesel-generated soot particles are often emitted with an organic coating composed primarily of lubricating oil and unburned fuel, as well as well as PAH compounds. Sulfuric acid has also been detected in diesel and aircraft-emitted soot particles. In the course of aging, these particle coatings may be substantially altered by chemical reactions and/or the deposition of other materials. Such processes transform the optical and CCN properties of the soot aerosols in ways that are not yet well understood. Our work over the past seven years consisted of laboratory research, instrument development and characterization, and field studies with the central focus of improving our understanding of the black carbon aerosol climate impacts. During the sixth year as well as during this seventh year (no

  8. Design of a mobile laboratory for ventilation studies and indoor air pollution monitoring. [Residences and commercial buildings

    Energy Technology Data Exchange (ETDEWEB)

    Berk, J.V.; Hollowell, C.D.; Lin, C.I.; Pepper, J.H.

    1978-04-01

    A mobile laboratory for research and development studies of ventilation requirements and energy utilization in residential and commercial buildings was designed and fabricated. The mobile laboratory contains sampling, calibrating, and monitoring systems to measure the concentration of CO, CO/sub 2/, NO, NO/sub 2/, NO/sub x/, O/sub 3/, and SO/sub 2/, and infiltration rates can be monitored continuously using a tracer gas system in which the tracer is injected into the room, mixed with room air, and monitored.

  9. Effects of Transgenic Cry 1 Ac plus CpTI Cotton on the Bioecology of Main Parasitoids in Laboratory Studies

    Institute of Scientific and Technical Information of China (English)

    CUI Jin-jie; VANDER Weft Wopke; MA Yah; LUO Jun-yu

    2008-01-01

    @@ Effects of transgenic CrylAc plus CpTI cotton (double genes cotton) on development of main parasitoids were studied in the laboratory.Compared with the traditional cotton,the differences of the moulting rate and adult weight of cotton aphid-Aphydius from double gene cotton field were not obvious.

  10. Pilot Inter-Laboratory Studies for Evaluating Weathering-Induced Release of Carbon Nanotubes from Solid Matrices

    Science.gov (United States)

    Nanomaterials are increasingly being used in polymer composites to enhance the properties of these materials. Here we present results of a pilot inter-laboratory study to simulate the effects of weathering on the potential release of multiwalled carbon nanotubes (MWCNT) from thei...

  11. Use of Long-Term E. Coli Cultures: To Study Generation of Genetic Diversity & Teach General Microbiology Laboratory Skills

    Science.gov (United States)

    Petrie, Angela; Finkel, Steven E.; Erbe, Jarrod

    2005-01-01

    A novel method of studying the generation of genetic diversity in an undergraduate microbiology laboratory is described. The basis of this approach is the accumulation of mutations that confer a competitive advantage, or growth advantage in stationary phase (GASP) phenotype, to E. coli grown in stationary phase for extended periods of time.

  12. Toxicologic Laboratory Findings in Cases Reported with Hanging Death: a Two-Year Retrospective Study in Northeast Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Ranjbar

    2013-09-01

    How to cite this article: Ranjbar R, Liaghat AR, Ranjbar A, Mohabbati H. Toxicologic Laboratory Findings in Cases Reported with Hanging Death: a Two-Year Retrospective Study in Northeast Iran. Asia Pac J Med Toxicol 2013;2:92-5.

  13. Comparative Study of the Effectiveness of Three Learning Environments: Hyper-Realistic Virtual Simulations, Traditional Schematic Simulations and Traditional Laboratory

    Science.gov (United States)

    Martinez, Guadalupe; Naranjo, Francisco L.; Perez, Angel L.; Suero, Maria Isabel; Pardo, Pedro J.

    2011-01-01

    This study compared the educational effects of computer simulations developed in a hyper-realistic virtual environment with the educational effects of either traditional schematic simulations or a traditional optics laboratory. The virtual environment was constructed on the basis of Java applets complemented with a photorealistic visual output.…

  14. Use of Long-Term E. Coli Cultures: To Study Generation of Genetic Diversity & Teach General Microbiology Laboratory Skills

    Science.gov (United States)

    Petrie, Angela; Finkel, Steven E.; Erbe, Jarrod

    2005-01-01

    A novel method of studying the generation of genetic diversity in an undergraduate microbiology laboratory is described. The basis of this approach is the accumulation of mutations that confer a competitive advantage, or growth advantage in stationary phase (GASP) phenotype, to E. coli grown in stationary phase for extended periods of time.

  15. Pilot Inter-Laboratory Studies for Evaluating Weathering-Induced Release of Carbon Nanotubes from Solid Matrices

    Science.gov (United States)

    Nanomaterials are increasingly being used in polymer composites to enhance the properties of these materials. Here we present results of a pilot inter-laboratory study to simulate the effects of weathering on the potential release of multiwalled carbon nanotubes (MWCNT) from thei...

  16. A Study of a Functional Approach to Defining Instructional Competencies and Measuring Faculty Performance in Medical Laboratory Technology.

    Science.gov (United States)

    Wiesenfeld, Laura Adina

    In order to develop a humanistic approach to evaluating faculty, a pilot study was conducted of 27 students and 14 instructors in an associate degree program for medical laboratory technicians. Selected personal dimensions of the sample population were examined to chart each individual's personality, theoretical learning preferences, modalities of…

  17. Comparative Study of the Sensitivity of Different Diagnostic Methods for the Laboratory Diagnosis of Buruli Ulcer Disease

    NARCIS (Netherlands)

    Herbinger, Karl-Heinz; Adjei, Ohene; Awua-Boateng, Nana-Yaa; Nienhuis, Willemien A.; Kunaa, Letitia; Siegmund, Vera; Nitschke, Joerg; Thompson, William; Klutse, Erasmus; Agbenorku, Pius; Schipf, Alexander; Reu, Simone; Racz, Paul; Fleischer, Bernhard; Beissner, Marcus; Fleischmann, Erna; Helfrich, Kerstin; van der Werf, Tjip S.; Loescher, Thomas; Bretzel, Gisela

    2009-01-01

    Background. Several diagnostic laboratory methods are available for case confirmation of Buruli ulcer disease. This study assessed the sensitivity of various diagnostic tests in relation to clinical presentation of the disease, type of diagnostic specimen, and treatment history. Methods. Swab sample

  18. Optogenetics in the Teaching Laboratory: Using Channelrhodopsin-2 to Study the Neural Basis of Behavior and Synaptic Physiology in "Drosophila"

    Science.gov (United States)

    Pulver, Stefan R.; Hornstein, Nicholas J.; Land, Bruce L.; Johnson, Bruce R.

    2011-01-01

    Here we incorporate recent advances in "Drosophila" neurogenetics and "optogenetics" into neuroscience laboratory exercises. We used the light-activated ion channel channelrhodopsin-2 (ChR2) and tissue-specific genetic expression techniques to study the neural basis of behavior in "Drosophila" larvae. We designed and implemented exercises using…

  19. Comparative Studies of Predation Among Feral, Commercially-Purchased, and Laboratory-Reared Predators

    Science.gov (United States)

    The predatory activities of commercially-purchased Hippodamia convergens Guèrin-Mèneville and two laboratory-reared strains of Geocoris punctipes (Say) were compared with their feral counterparts. In single prey choice feeding tests, commercially-purchased and feral H. convergens were provided copi...

  20. Isentropic Compression Studies at the Los Alamos National High Magnetic Field Laboratory

    Science.gov (United States)

    2011-06-01

    D.G. Tasker, C.H. Mielke , G. Rodriguez, and D.W. Rickel Los Alamos National Laboratory, WX-6, MS J566 Los Alamos, NM 87545, USA Abstract...07E108-3. [3] D. G. Tasker, C. H. Mielke , G. Rodriguez, and D. G. Rickel, "A Simple Isentropic Compression Experiment (ICE) Machine," presented at