Reduced infant birthweight consequent upon maternal exposure to severe life events

DEFF Research Database (Denmark)

Khashan, Ali; McNamee, R.; Pedersen, Marianne Giørtz

2008-01-01

OBJECTIVE: To investigate the association between maternal exposure to severe life events and fetal growth (birthweight and small for gestational age). Stress has been associated with adverse pregnancy outcome. METHODS: Mothers of 1.38 million singleton live births in Denmark between January 1......). There was a significant association between maternal exposure to death of a relative and risk of a baby weighing below the 10th percentile (adjusted relative risk (RR) = 1.17, 95% CI = 1.13, 1.22) and 5th percentile (adjusted RR = 1.22, 95% CI = 1.15, 1.29). CONCLUSIONS: Mothers exposed to severe life events before...... conception or during pregnancy have babies with significantly lower birthweight. If this association is causal, the potential mechanisms of stress-related effects on birthweight include changes in lifestyle due to the exposure and stress-related dysregulation of the hypothalamic-pituitary-adrenal axis during...

Comparing the reported burn conditions for different severity burns in porcine models: a systematic review.

Science.gov (United States)

Andrews, Christine J; Cuttle, Leila

2017-12-01

There are many porcine burn models that create burns using different materials (e.g. metal, water) and different burn conditions (e.g. temperature and duration of exposure). This review aims to determine whether a pooled analysis of these studies can provide insight into the burn materials and conditions required to create burns of a specific severity. A systematic review of 42 porcine burn studies describing the depth of burn injury with histological evaluation is presented. Inclusion criteria included thermal burns, burns created with a novel method or material, histological evaluation within 7 days post-burn and method for depth of injury assessment specified. Conditions causing deep dermal scald burns compared to contact burns of equivalent severity were disparate, with lower temperatures and shorter durations reported for scald burns (83°C for 14 seconds) compared to contact burns (111°C for 23 seconds). A valuable archive of the different mechanisms and materials used for porcine burn models is presented to aid design and optimisation of future models. Significantly, this review demonstrates the effect of the mechanism of injury on burn severity and that caution is recommended when burn conditions established by porcine contact burn models are used by regulators to guide scald burn prevention strategies. © 2017 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

The mediating effect of mindful non-reactivity in exposure-based cognitive behavior therapy for severe health anxiety.

Science.gov (United States)

Hedman, Erik; Hesser, Hugo; Andersson, Erik; Axelsson, Erland; Ljótsson, Brjánn

2017-08-01

Exposure-based cognitive behavior therapy (CBT) has been shown to be effective in the treatment of severe health anxiety, but little is known about mediators of treatment effect. The aim of the present study was to investigate mindful non-reactivity as a putative mediator of health anxiety outcome using data from a large scale randomized controlled trial. We assessed mindful non-reactivity using the Five Facets Mindfulness Questionnaire-Non-Reactivity scale (FFMQ-NR) and health anxiety with the Short Health Anxiety Inventory (SHAI). Participants with severe health anxiety (N=158) were randomized to internet-delivered exposure-based CBT or behavioral stress management (BSM) and throughout the treatment, both the mediator and outcome were measured weekly. As previously reported, exposure-based CBT was more effective than BSM in reducing health anxiety. In the present study, latent process growth modeling showed that treatment condition had a significant effect on the FFMQ-NR growth trajectory (α-path), estimate=0.18, 95% CI [0.04, 0.32], p=.015, indicating a larger increase in mindful non-reactivity among participants receiving exposure-based CBT compared to the BSM group. The FFMQ-NR growth trajectory was significantly correlated with the SHAI trajectory (β-path estimate=-1.82, 95% CI [-2.15, -1.48], panxiety. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physiological responses and manual performance in humans following repeated exposure to severe cold at night.

Science.gov (United States)

Ozaki, H; Nagai, Y; Tochihara, Y

2001-04-01

We evaluated human physiological responses and the performance of manual tasks during exposure to severe cold (-25 degrees C) at night (0300-0500 hours) and in the afternoon (1500-1700 hours). Thirteen male students wearing standard cold protective clothing occupied a severely cold room (-25 degrees C) for 20 min, and were then transferred to a cool room (10 degrees C) for 20 min. This pattern of exposure was repeated three times, for a total time of exposure to extreme cold of 60 min. The experiments were started either at 1500 hours or 0300 hours and measurements of rectal temperature, skin temperature, blood pressure, performance in a counting task, hand tremor, and subjective responses were made in each condition. At the end of the experiment at night the mean decrease in rectal temperature [0.68 (SEM 0.04) degree C] was significantly greater than that at the end of the experiment in the afternoon [0.55 (SEM 0.08) degree C, P second cold exposure at night the mean increase in diastolic blood pressure [90 (SEM 2.0) mmHg] was significantly greater than that at the end of the second cold exposure in the afternoon [82 (SEM 2.8) mmHg, P second cold exposure at night, mean finger skin temperature [11.8 (SEM 0.8) degrees C] was significantly higher than that at the comparable time in the afternoon [9.0 (SEM 0.7) degrees C, P second cold exposure at night [25.6 (SEM 1.5) degrees C] was significantly higher than in the afternoon [20.1 (SEM 0.8) degrees C, P < 0.01]. The increased skin temperatures in the periphery resulted in increased heat loss. Since peripheral skin temperatures were highest at night, the subjects noted diminished sensations of thermal cold and pain at that time. Manual dexterity at the end of the first cold exposure at night [mean 83.7 (SEM 3.6) times.min-1] had decreased significantly more than at the end of the first cold exposure in the afternoon [mean 89.4 (SEM 3.5) times.min-1, P < 0.01]. These findings of a lowered rectal temperature and

Prevalence of interpersonal trauma exposure and trauma-related disorders in severe mental illness

NARCIS (Netherlands)

Mauritz, M.W.; Goossens, P.J.J.; Draijer, N.; Achterberg, T. van

2013-01-01

BACKGROUND: Interpersonal trauma exposure and trauma-related disorders in people with severe mental illness (SMI) are often not recognized in clinical practice. OBJECTIVE: To substantiate the prevalence of interpersonal trauma exposure and trauma-related disorders in people with SMI. METHODS: We

Prevalence of interpersonal trauma exposure and trauma-related disorders in severe mental illness

NARCIS (Netherlands)

Mauritz, M.W.; Goossens, P.J.J.; Draijer, N.; van Achterberg, T.

2013-01-01

Background: Interpersonal trauma exposure and trauma-related disorders in people with severe mental illness (SMI) are often not recognized in clinical practice. Objective: To substantiate the prevalence of interpersonal trauma exposure and trauma-related disorders in people with SMI. Methods: We

Contributions of dust exposure and cigarette smoking to emphysema severity in coal miners in the United States

Energy Technology Data Exchange (ETDEWEB)

Kuempel, E.D.; Wheeler, M.W.; Smith, R.J.; Vallyathan, V.; Green, F.H.Y. [NIOSH, Cincinnati, OH (United States)

2009-08-15

Previous studies have shown associations between dust exposure or lung burden and emphysema in coal miners, although the separate contributions of various predictors have not been clearly demonstrated. The objective was to quantitatively evaluate the relationship between cumulative exposure to respirable coal mine dust, cigarette smoking, and other factors on emphysema severity. The study group included 722 autopsied coal miners and nonminers in the United States. Data on work history, smoking, race, and age at death were obtained from medical records and questionnaire completed by next-of-kin. Emphysema was classified and graded using a standardized schema. Job-specific mean concentrations of respirable coal mine dust were matched with work histories to estimate cumulative exposure. Relationships between various metrics of dust exposure (including cumulative exposure and lung dust burden) and emphysema severity were investigated in weighted least squares regression models. Emphysema severity was significantly elevated in coal miners compared with nonminers among ever- and never-smokers (P < 0.0001). Cumulative exposure to respirable coal mine dust or coal dust retained in the lungs were significant predictors of emphysema severity (P < 0.0001) after accounting for cigarette smoking, age at death, and race. The contributions of coal mine dust exposure and cigarette smoking were similar in predicting emphysema severity averaged over this cohort. Coal dust exposure, cigarette smoking, age, and race are significant and additive predictors of emphysema severity in this study.

Failure Mode Estimation of Wolsong Unit 1 Containment Building with respect to Severe Accident Condition

International Nuclear Information System (INIS)

Hahm, Dae Gi; Choi, In Kil

2009-01-01

The containment buildings in a nuclear power plant (NPP) are final barriers against the exposure of harmful radiation materials at severe accident condition. Since the accident at Three Mile Island nuclear plant in 1979, it has become necessary to evaluate the internal pressure capacity of the containment buildings for the assessment of the safety of nuclear power plants. According to this necessity, many researchers including Yonezawa et al. and Hu and Lin analyzed the ultimate capacity of prestressed concrete containments subjected to internal pressure which can be occurred at sever accident condition. Especially in Wolsong nuclear power plant, the Unit 1 containment structures were constructed in the late 1970 to early 1980, so that the end of its service life will be reached in near future. Since that the complete decommission and reconstruction of the NPP may cause a huge expenses, an extension of the service time can be a cost-effective alternative. To extend the service time of NPP, an overall safety evaluation of the containment building under severe accident condition should be performed. In this study, we assessed the pressure capacity of Wolsong Unit 1 containment building under severe accident, and estimated the responses at all of the probable critical areas. Based on those results, we found the significant failure modes of Wolsong Unit 1 containment building with respect to the severe accident condition. On the other hand, for the aged NPP, the degradation of their structural performance must also be explained in the procedure of the internal pressure capacity evaluation. Therefore, in this study, we performed a parametric study on the degradation effects and evaluated the internal pressure capacity of Wolsong Unit 1 containment building with considering aging and degradation effects

Nano-scale topography of bearing surface in advanced alumina/zirconia hip joint before and after severe exposure in water vapor environment.

Science.gov (United States)

Pezzotti, Giuseppe; Saito, Takuma; Padeletti, Giuseppina; Cossari, Pierluigi; Yamamoto, Kengo

2010-06-01

The aim of this study was to perform a surface morphology assessment with nanometer scale resolution on femoral heads made of an advanced zirconia toughened alumina (ZTA) composite. Femoral heads were characterized to a degree of statistical accuracy in the as-received state and after exposures up to 100 h in severe vapor-moist environment. Surface screening was made using an atomic force microscope (AFM). Scanning was systematically repeated on portions of surface as large as several tens of micrometers, randomly selected on the head surface, to achieve sufficient statistical reliability without lowering the nanometer-scale spatial resolution of the roughness measurement. No significant difference was found in the recorded values of surface roughness after environmental exposure (at 134 degrees C, under 2 bar), which was always comparable to that of the as-received head. Surface roughness safely lay <10 nm after environmental exposures up to 100 h, which corresponded to an exposure time in vivo of several human lifetimes (i.e., according to an experimentally derived thermal activation energy). In addition, the roughness results were significantly (about one order of magnitude) lower as compared to those recorded on femoral heads made of monolithic zirconia tested under the same conditions. (c) 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Smoke exposure and associated health effects across several fire seasons and locations in the Western US

Science.gov (United States)

O'Dell, K.; Ford, B.; Gan, R.; Liu, J.; Lassman, W.; Burke, M.; Pfister, G.; Vaidyanathan, A.; Volckens, J.; Magzamen, S.; Fischer, E. V.; Pierce, J. R.

2017-12-01

Wildfires are a significant source of particulate matter in the western United States. Wildfire activity in this region has increased over the past few decades and is projected to continue to increase further due to warmer and drier conditions. Particulate matter with diameters smaller than or equal to 2.5 microns (PM2.5) has known adverse effects on human health. However, due to an inconsistent association of wildfire PM2.5 and several disease outcomes, it is unclear if wildfire PM exerts similar health impacts as anthropogenic PM. Improved wildfire smoke exposure estimates are needed to gain a clearer understanding of the health impacts of wildfire PM2.5. Characterizing PM2.5 concentrations from wildfire smoke is challenging due to the transient nature of smoke. Current methods of determining smoke exposure rely on satellite retrievals of aerosol optical depth (AOD), estimates from chemical transport models (CTMs), or values reported by surface monitoring sites; each of these data sources has some limitations. To improve the accuracy of our exposure estimates, we developed new methods to blend these data. Our results indicate that blending information from the above-mentioned data sources along with counts of wildfire-smoke-related social-media posts results in better characterization of smoke exposure than any individual tool. We link our daily smoke PM2.5 exposure estimates with hospitalization and urgent-care admission data from Washington, Oregon, and Colorado during several fire seasons as well as prescription filling data from Oregon. We find a robust relationship, where a 10 μg m-3 increase in smoke is significantly associated with a 9.5% (95% CI: 6.2, 12.9) increase in the rate of asthma admissions and a 7.7% increase (95% CI: 6.5. 8.8) in the risk for respiratory rescue medication prescription refills. There was no significant association between smoke exposure and any cardiovascular endpoints. Our findings support the association of wildfire smoke

Long-Term Flexural Behaviors of GFRP Reinforced Concrete Beams Exposed to Accelerated Aging Exposure Conditions

Directory of Open Access Journals (Sweden)

Yeonho Park

2014-06-01

Full Text Available This study investigates the impact of accelerated aging conditions on the long-term flexural behavior and ductility of reinforced concrete (RC members with glass fiber-reinforced polymer (GFRP bars (RC-GFRP specimen and steel bars (RC-steel specimen. A total of thirty six specimens were designed with different amounts of reinforcement with three types of reinforcing bars (i.e., helically wrapped GFRP, sand-coated surface GFRP and steel. Eighteen specimens were subjected to sustained loads and accelerated aging conditions (i.e., 47 °C and 80% relative humidity in a chamber. The flexural behavior of specimens under 300-day exposure was compared to that of the companion specimens without experiencing accelerated aging conditions. Results indicate that the accelerated aging conditions reduced flexural capacity in not only RC-steel, but also RC-GFRP specimens, with different rates of reduction. Different types of GFRP reinforcement exhibited different rates of degradation of the flexural capacity when embedded in concrete under the same exposure conditions. Several existing models were compared with experimental results for predicting the deflection and deformability index for specimens. Bischoff and Gross’s model exhibited an excellent prediction of the time-dependent deflections. Except for the deformability index proposed by Jaeger, there was no general trend related to the aging duration. This study recommends the need for further investigation on the prediction of the deformability index.

Neuropsychological alterations in mercury intoxication persist several years after exposure.

Science.gov (United States)

Zachi, Elaine Cristina; Taub, Anita; Faria, Marcília de Araújo Medrado; Ventura, Dora Fix

2008-01-01

Elemental mercury is a liquid toxic metal widely used in industry. Occupational exposure occurs mainly via inhalation. Previously, neuropsychological assessment detected deficits in former workers of a fluorescent lamp plant who had been exposed to elemental mercury vapor and were away from exposure for several years at the time of examination. The purpose of this work was to reexamine these functions after 18 months in order to evaluate their progression. Thirteen participants completed tests of attention, inhibitory control, verbal/visual memory, psychomotor speed, verbal fluency, visuomotor ability, executive function, semantic knowledge, and depression and anxiety inventories on 2 separate occasions. At baseline, the former workers indicated slower psychomotor and information processing speed, verbal spontaneous recall memory impairment, and increased depression and anxiety symptoms compared to controls (Precovery of functions, the neuropsychological effects related to mercury exposure are found to persist for many years.

Bright Light Delights: Effects of Daily Light Exposure on Emotions, Restactivity Cycles, Sleep and Melatonin Secretion in Severely Demented Patients.

Science.gov (United States)

Münch, Mirjam; Schmieder, Michael; Bieler, Katharina; Goldbach, Rolf; Fuhrmann, Timo; Zumstein, Naomi; Vonmoos, Petra; Scartezzini, Jean-Louis; Wirz-Justice, Anna; Cajochen, Christian

2017-01-01

We tested whether the effects of a dynamic lighting system are superior to conventional lighting on emotions, agitation behaviour, quality of life, melatonin secretion and circadian restactivity cycles in severely demented patients. As a comparison, an age matched control patient group was exposed to conventional lighting. For none of the output measures were significant differences between the two lighting conditions found during the 8 study weeks in fall/winter. Thus, we divided the patient cohort (n = 89) into two groups, solely based on the median of their daily individual light exposure. Patients with higher average daily light exposure (>417 lx) showed significantly longer emotional expressions of pleasure and alertness per daily observations than patients with lower daily light exposure. Moreover, they had a higher quality of life, spent less time in bed, went to bed later and initiated their sleep episodes later, even though the two groups did not differ with respect to age, severity of cognitive impairment and mobility. In general, men were more agitated, had shorter sleep with more wake episodes, had a lower circadian amplitude of relative rest-wake activity and interdaily circadian stability than women. In particular, lower daily light exposures significantly predicted lower circadian amplitudes of rest-activity cycles in men but not in women. This may indicate sex specific susceptibility to daily light exposures for rest-activity regulation in older demented patients. Our results provide evidence that a higher daily light exposure has beneficial effects on emotions and thus improved quality of life in a severely demented patient group. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Prevalence of interpersonal trauma exposure and trauma-related disorders in severe mental illness

OpenAIRE

Mauritz, Maria W.; Goossens, Peter J.J.; Draijer, Nel; Achterberg, Theo van

2013-01-01

Background: Interpersonal trauma exposure and trauma-related disorders in people with severe mental illness (SMI) are often not recognized in clinical practice.Objective: To substantiate the prevalence of interpersonal trauma exposure and trauma-related disorders in people with SMI.Methods: We conducted a systematic review of four databases (1980-2010) and then described and analysed 33 studies in terms of primary diagnosis and instruments used to measure trauma exposure and traumarelated dis...

Basal exposure therapy: A new approach for treatment resistant patients with severe and comorbid mental disorders

Directory of Open Access Journals (Sweden)

Didrik Heggdal

2016-12-01

Full Text Available New treatment approaches are needed for patients with severe and composite mental disorders who appear resistant to conventional treatments. Such treatment resistant patients often have diagnoses of psychotic or bipolar disorders or severe personality disorders and comorbid conditions. Here we evaluate Basal Exposure Therapy (BET, a novel ward-integrated psychotherapeutic approach for these patients. Central to BET is the conceptualization of undifferentiated existential fear as basic to the patients’ problem, exposure to this fear, and the therapeutic platform Complementary External Regulation (CER which integrates and governs the totality of interventions throughout the treatment process. BET is administered at a locked-door ward with six patient beds and 13.5 full time employees, including a psychiatrist and two psychologists. Thirty-eight patients who had completed BET were included, all but two being female, mean age 29.9 years. Fourteen patients had a diagnosis of schizophrenia or schizoaffective disorder (F20/25, eight had bipolar disorder or recurrent depressive disorder (F31/33, eight had diagnoses in the F40-49 domain (anxiety, stress, dissociation, five were diagnosed with emotionally unstable personality disorder (F60.3, and three patients had other diagnoses. Twenty of the patients (53% had more than one ICD-10 diagnosis. Average treatment time in BET was 13 months, ranging from 2 to 72 months. Time-series data show significant improvements in symptoms and functioning from enrolment to discharge, with effect sizes at 0.76 for the Dissociation Experience Scale, 0.93 for the Brief Symptom Inventory, 1.47 for the Avoidance and Action Questionnaire, and 1.42 and 1.56, respectively for the functioning and symptom subscales of the Global Assessment of Functioning Scale. In addition, the patients used significantly less antiepileptic, antipsychotic, anxiolytic and antidepressant medications at discharge than at treatment enrolment

Large errors and severe conditions

CERN Document Server

Smith, D L; Van Wormer, L A

2002-01-01

Physical parameters that can assume real-number values over a continuous range are generally represented by inherently positive random variables. However, if the uncertainties in these parameters are significant (large errors), conventional means of representing and manipulating the associated variables can lead to erroneous results. Instead, all analyses involving them must be conducted in a probabilistic framework. Several issues must be considered: First, non-linear functional relations between primary and derived variables may lead to significant 'error amplification' (severe conditions). Second, the commonly used normal (Gaussian) probability distribution must be replaced by a more appropriate function that avoids the occurrence of negative sampling results. Third, both primary random variables and those derived through well-defined functions must be dealt with entirely in terms of their probability distributions. Parameter 'values' and 'errors' should be interpreted as specific moments of these probabil...

Impaired vascular function after exposure to diesel exhaust generated at urban transient running conditions

Directory of Open Access Journals (Sweden)

Westerholm Roger

2010-07-01

Full Text Available Abstract Background Traffic emissions including diesel engine exhaust are associated with increased respiratory and cardiovascular morbidity and mortality. Controlled human exposure studies have demonstrated impaired vascular function after inhalation of exhaust generated by a diesel engine under idling conditions. Objectives To assess the vascular and fibrinolytic effects of exposure to diesel exhaust generated during urban-cycle running conditions that mimic ambient 'real-world' exposures. Methods In a randomised double-blind crossover study, eighteen healthy male volunteers were exposed to diesel exhaust (approximately 250 μg/m3 or filtered air for one hour during intermittent exercise. Diesel exhaust was generated during the urban part of the standardized European Transient Cycle. Six hours post-exposure, vascular vasomotor and fibrinolytic function was assessed during venous occlusion plethysmography with intra-arterial agonist infusions. Measurements and Main Results Forearm blood flow increased in a dose-dependent manner with both endothelial-dependent (acetylcholine and bradykinin and endothelial-independent (sodium nitroprusside and verapamil vasodilators. Diesel exhaust exposure attenuated the vasodilatation to acetylcholine (P Conclusion Exposure to diesel exhaust generated under transient running conditions, as a relevant model of urban air pollution, impairs vasomotor function and endogenous fibrinolysis in a similar way as exposure to diesel exhaust generated at idling. This indicates that adverse vascular effects of diesel exhaust inhalation occur over different running conditions with varying exhaust composition and concentrations as well as physicochemical particle properties. Importantly, exposure to diesel exhaust under ETC conditions was also associated with a novel finding of impaired of calcium channel-dependent vasomotor function. This implies that certain cardiovascular endpoints seem to be related to general diesel

The impact of environmental conditions on human performance: A handbood of environmental exposures. Volume 1

International Nuclear Information System (INIS)

Echeverria, D.; Barnes, V.; Bittner, A.

1994-09-01

A comprehensive review of the technical literature was conducted regarding the impact of environmental conditions on hyman performance applicable to nuclear power plant workers. The environmental conditions considered were vibration, noise, heat, cold, and light. Research staff identified potential human performance deficits (e.g., decreased dexterity, impaired vision, hearing loss, memory deficiency) along a continuum of increasing occupational exposure, ranging from exposures that result in no deficit to exposures that resulted in significant performance problems. Specific deficits were included in the report if there was sound scientific evidence that environmental exposure resulted in those performance deficits. The levels associated with each deficit were then compared to the protection afforded by existing occupational exposure standards. Volume 1 is a handbook for use by NRC inspectors to help them determine the impact of specific environmental conditions on licensee personnel performance. it discusses the units used to measure each condition, discusses the effects of the condition on task performance, presents an example of the assessment of each condition in a nuclear power plant, and discusses potential methods for reducing the effects of

Sodium bicarbonate supplementation improves severe-intensity intermittent exercise under moderate acute hypoxic conditions.

Science.gov (United States)

Deb, Sanjoy K; Gough, Lewis A; Sparks, S Andy; McNaughton, Lars R

2018-03-01

Acute moderate hypoxic exposure can substantially impair exercise performance, which occurs with a concurrent exacerbated rise in hydrogen cation (H + ) production. The purpose of this study was therefore, to alleviate this acidic stress through sodium bicarbonate (NaHCO 3 ) supplementation and determine the corresponding effects on severe-intensity intermittent exercise performance. Eleven recreationally active individuals participated in this randomised, double-blind, crossover study performed under acute normobaric hypoxic conditions (FiO 2 % = 14.5%). Pre-experimental trials involved the determination of time to attain peak bicarbonate anion concentrations ([HCO 3 - ]) following NaHCO 3 ingestion. The intermittent exercise tests involved repeated 60-s work in their severe-intensity domain and 30-s recovery at 20 W to exhaustion. Participants ingested either 0.3 g kg bm -1 of NaHCO 3 or a matched placebo of 0.21 g kg bm -1 of sodium chloride prior to exercise. Exercise tolerance (+ 110.9 ± 100.6 s; 95% CI 43.3-178 s; g = 1.0) and work performed in the severe-intensity domain (+ 5.8 ± 6.6 kJ; 95% CI 1.3-9.9 kJ; g = 0.8) were enhanced with NaHCO 3 supplementation. Furthermore, a larger post-exercise blood lactate concentration was reported in the experimental group (+ 4 ± 2.4 mmol l -1 ; 95% CI 2.2-5.9; g = 1.8), while blood [HCO 3 - ] and pH remained elevated in the NaHCO 3 condition throughout experimentation. In conclusion, this study reported a positive effect of NaHCO 3 under acute moderate hypoxic conditions during intermittent exercise and therefore, may offer an ergogenic strategy to mitigate hypoxic induced declines in exercise performance.

Does pre-exposure to warming conditions increase Mytilus galloprovincialis tolerance to Hg contamination?

Science.gov (United States)

Freitas, Rosa; Coppola, Francesca; Henriques, Bruno; Wrona, Fredrick; Figueira, Etelvina; Pereira, Eduarda; Soares, Amadeu M V M

2017-12-01

The degree to which marine invertebrate populations can tolerate extreme weather events, such as short-term exposure to high temperatures, and the underlying biochemical response mechanisms are not yet fully understood. Furthermore, scarce information is available on how marine organisms respond to the presence of pollutants after exposure to heat stress conditions. Therefore, the present study aimed to understand how the mussel Mytilus galloprovincialis responds to Hg pollution after pre-exposure to warming conditions. Mussels were exposed to control (17°C) and warming (21°C) conditions during 14days, followed by Hg contamination during 28days under different temperature regimes (17 and 21°C). The results obtained demonstrated significantly higher Hg concentrations in mussels under 17°C during the entire experiment than in organisms exposed to 21°C during the same period, which resulted in higher oxidative stress in mussels under control temperature. Significantly higher Hg concentrations were also observed in mussels pre-exposed to 21°C followed by a 17°C exposure comparing with organisms maintained the entire experiment at 21°C. These results may be explained by higher metabolic capacity in organisms exposed to 17°C after pre-exposure to 21°C that although induced antioxidant defences were not enough to prevent oxidative stress. No significant differences in terms of Hg concentration were found between mussels exposed to 17°C during the entire experiment and organisms pre-exposed to 21°C followed by a 17°C exposure, leading to similar oxidative stress levels in mussels exposed to both conditions. Therefore, our findings demonstrated that pre-exposure to warming conditions did not change mussels' accumulation and tolerance to Hg in comparison to Hg contaminated mussels maintained at control temperature. Furthermore, the present study indicate that organisms maintained under warming conditions for long periods may prevent the accumulation of

Radon dosimetry: a review of radon and radon daughter exposure conditions in dwellings and other structures

International Nuclear Information System (INIS)

Ryan, M.T.; Goldsmith, W.A.; Poston, J.W.; Haywood, F.F.; Witherspoon, J.P.

1983-07-01

Within the past few years several situations have been brought to light which indicate an increased radiation exposure of certain segments of the general population caused by human activities. The most widely publicized activities are those associated with the mining and milling of uranium in the western United States, the phosphate industry in Florida, and those potential problems represented by former Manhattan Engineer District sites. One of the primary problems involves exposure to radon and radon daughters which are released from large waste piles or, in some cases, evolve from backfill and construction materials used in homes, schools, and other buildings. This report presents a review of the available data on radon and radon daughter concentrations in dwellings and other structures. The primary objectives were to compile and tabulate pertinent radon exposure data and to prepare a statistical summary of the data which will be useful in the prediction of normal levels of radon and radon daughter concentrations in these structures. In addition, other parameters associated with radon exposure conditions are presented and discussed

Prenatal tobacco smoke exposure, risk of schizophrenia, and severity of positive/negative symptoms.

Science.gov (United States)

Stathopoulou, Anastasia; Beratis, Ion N; Beratis, Stavroula

2013-08-01

Prenatal exposure to cigarette smoke causes chronic fetal hypoxia, dysregulation of endocrine equilibrium, and disruption of fetal neurodevelopment associated with brain malfunction, all of which potentially could induce vulnerability to schizophrenia. A total of 212 schizophrenia patients aged 14-30years, and 212 matched controls were studied. Prenatal tobacco smoke exposure of the schizophrenia patients was compared to that of the normal controls by applying logistic regression analysis and controlling for several confounding factors. The outcomes of interest were comparison of the frequency of maternal and paternal smoking between patients and controls, as well as the severity of positive and negative symptoms between the offspring of smoking and nonsmoking parents. Among the mothers of schizophrenia patients and controls, 92 (43.4%) and 46 (21.7%) smoked, respectively. Maternal smoking during pregnancy had a significant unique contribution on increasing the risk for development of schizophrenia (p=0.001), and a greater severity of negative symptoms (p=0.023). Paternal smoking did not have a significant effect on the risk of schizophrenia, or severity of negative symptoms. The findings suggest that maternal smoking during pregnancy puts offspring at an increased risk for later schizophrenia, with increased severity of negative symptoms. Given the wide practice of smoking during pregnancy, fetal exposure to tobacco smoke could be a major preventable neurodevelopmental factor that increases vulnerability to schizophrenia. Copyright © 2013 Elsevier B.V. All rights reserved.

Concrete under severe conditions. Environment and loading

International Nuclear Information System (INIS)

2007-01-01

The objective of the CONSEC Conferences is to focus on concrete infrastructures, either subjected to severe environment or severe loading, or any combination of severe conditions. Experience from the performance of existing concrete structures, and especially under severe environmental conditions, severe accidental loading or extended lifespan, has demonstrated the need for better integration of structural and durability design, new design concepts including reliability-based durability design, performance-based material requirements, structural robustness, and an improved basis for documentation of obtained construction quality and durability properties during concrete construction. An improved basis for operation and preventive maintenance of concrete structures including repairs and retrofitting is also very important. Premature corrosion of reinforcing steel, inadequate structural design for seismic or blast loading, are examples of reduced service life of concrete structures that not only represent technical and economical problems, but also a huge waste of natural resources and hence also, an environmental and ecological problem. Experience of structures effectively submitted to severe conditions represents a unique benchmark for quantifying the actual safety and durability margin of concrete structures. In fact for several reasons, most concrete design codes, job specifications and other requirements for concrete structures have frequently shown to yield insufficient and unsatisfactory results and ability to solve the above problems, as well as issues raised by specific very long-term or very severe requirements for nuclear and industrial waste management, or civil works of strategic relevance. Recently available high to ultra-high performance concrete may find rational and valuable application in such cases. It is very important, therefore, to bring people with different professional backgrounds together to exchange experience and develop multi

Analyzing Traffic Crash Severity in Work Zones under Different Light Conditions

Directory of Open Access Journals (Sweden)

Xinxin Wei

2017-01-01

Full Text Available Previous studies have investigated various factors that contribute to the severity of work zone crashes. However, little has been done on the specific effects of light conditions. Using the data from the Enhanced Tennessee Roadway Information Management System (E-TRIMS, crashes that occurred in the Tennessee work zones during 2003–2015 are categorized into three light conditions: daylight, dark-lighted, and dark-not-lighted. One commonly used decision tree method—Classification and Regression Trees (CART—is adopted to investigate the factors contributing to crash severity in highway work zones under these light conditions. The outcomes from the three decision trees with differing light conditions show significant differences in the ranking and importance of the factors considered in the study, thereby indicating the necessity of examining traffic crashes according to light conditions. By separately considering the crash characteristics under different light conditions, some new findings are obtained from this study. The study shows that an increase in the number of lanes increases the crash severity level in work zones during the day while decreasing the severity at night. Similarly, drugs and alcohol are found to increase the severity level significantly under the dark-not-lighted condition, while they have a limited influence under daylight and dark-lighted conditions.

Comments on the exposure distance as a factor of severity of A-bomb cataracts

Energy Technology Data Exchange (ETDEWEB)

Sugimoto, S [Sugimoto Ophthalmological Clinic, Hiroshima (Japan)

1976-09-01

In the study of A-bomb disorders, it is important in decision of exposure dose to consider not only exposure distance from the hypocenter but also shelter factors, and 8 cases were reported as examples. Group 1 (4 cases) was exposed to A-bomb in the train 750 m east of the hypocenter, and group 2 (4 cases) was exposed in the concrete steel building 620 m east of the hypocenter. Age, exposure distance, exposure place, shelter condition, wounds, acute symptoms due to A-bomb exposure, radiation dose, condition of turbidity of the crystalline lens, effect of A-bomb on visual acuity of eight cases were listed in table. Group 1 was exposed to A-bomb at the place 130 m from the place where group 2 was exposed, but the exposed dose of group 1 was equivalent to twice that of group 2. Acute symptoms due to A-bomb exposure, turbidity of the crystalline lens, and effect of A-bomb on visual acuity were by far stronger in group 1 than in group 2. It was stressed that physical history and treatment course of the patients with A-bomb cataract were enough to be important materials on the study of A-bomb disorders.

Plausible Roles for RAGE in Conditions Exacerbated by Direct and Indirect (Secondhand) Smoke Exposure.

Science.gov (United States)

Lewis, Joshua B; Hirschi, Kelsey M; Arroyo, Juan A; Bikman, Benjamin T; Kooyman, David L; Reynolds, Paul R

2017-03-17

Approximately 1 billion people smoke worldwide, and the burden placed on society by primary and secondhand smokers is expected to increase. Smoking is the leading risk factor for myriad health complications stemming from diverse pathogenic programs. First- and second-hand cigarette smoke contains thousands of constituents, including several carcinogens and cytotoxic chemicals that orchestrate chronic inflammatory responses and destructive remodeling events. In the current review, we outline details related to compromised pulmonary and systemic conditions related to smoke exposure. Specifically, data are discussed relative to impaired lung physiology, cancer mechanisms, maternal-fetal complications, cardiometabolic, and joint disorders in the context of smoke exposure exacerbations. As a general unifying mechanism, the receptor for advanced glycation end-products (RAGE) and its signaling axis is increasingly considered central to smoke-related pathogenesis. RAGE is a multi-ligand cell surface receptor whose expression increases following cigarette smoke exposure. RAGE signaling participates in the underpinning of inflammatory mechanisms mediated by requisite cytokines, chemokines, and remodeling enzymes. Understanding the biological contributions of RAGE during cigarette smoke-induced inflammation may provide critically important insight into the pathology of lung disease and systemic complications that combine during the demise of those exposed.

Chronic plus binge ethanol exposure causes more severe pancreatic injury and inflammation

Energy Technology Data Exchange (ETDEWEB)

Ren, Zhenhua [Department of Anatomy, School of Basic Medicine, Anhui Medical University, Hefei, Anhui, China 230032 (China); Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Yang, Fanmuyi; Wang, Xin; Wang, Yongchao; Xu, Mei; Frank, Jacqueline A. [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Ke, Zun-ji [Department of Biochemistry, Shanghai University of Traditional Chinese Medicine, Shanghai 201203 (China); Zhang, Zhuo; Shi, Xianglin [Department of Toxicology and Cancer Biology, University of Kentucky College of Medicine, Lexington, KY 40536 (United States); Luo, Jia, E-mail: jialuo888@uky.edu [Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, KY 40536 (United States)

2016-10-01

Alcohol abuse increases the risk for pancreatitis. The pattern of alcohol drinking may impact its effect. We tested a hypothesis that chronic ethanol consumption in combination with binge exposure imposes more severe damage to the pancreas. C57BL/6 mice were divided into four groups: control, chronic ethanol exposure, binge ethanol exposure and chronic plus binge ethanol exposure. For the control group, mice were fed with a liquid diet for two weeks. For the chronic ethanol exposure group, mice were fed with a liquid diet containing 5% ethanol for two weeks. In the binge ethanol exposure group, mice were treated with ethanol by gavage (5 g/kg, 25% ethanol w/v) daily for 3 days. For the chronic plus binge exposure group, mice were fed with a liquid diet containing 5% ethanol for two weeks and exposed to ethanol by gavage during the last 3 days. Chronic and binge exposure alone caused minimal pancreatic injury. However, chronic plus binge ethanol exposure induced significant apoptotic cell death. Chronic plus binge ethanol exposure altered the levels of alpha-amylase, glucose and insulin. Chronic plus binge ethanol exposure caused pancreatic inflammation which was shown by the macrophages infiltration and the increase of cytokines and chemokines. Chronic plus binge ethanol exposure increased the expression of ADH1 and CYP2E1. It also induced endoplasmic reticulum stress which was demonstrated by the unfolded protein response. In addition, chronic plus binge ethanol exposure increased protein oxidation and lipid peroxidation, indicating oxidative stress. Therefore, chronic plus binge ethanol exposure is more detrimental to the pancreas. - Highlights: • Chronic plus binge alcohol drinking causes more pancreatic injury. • Chronic plus binge alcohol drinking induces more pancreatic inflammation. • Chronic plus binge alcohol causes more endoplasmic reticulum stress and oxidative stress.

Chronic plus binge ethanol exposure causes more severe pancreatic injury and inflammation

International Nuclear Information System (INIS)

Ren, Zhenhua; Yang, Fanmuyi; Wang, Xin; Wang, Yongchao; Xu, Mei; Frank, Jacqueline A.; Ke, Zun-ji; Zhang, Zhuo; Shi, Xianglin; Luo, Jia

2016-01-01

Alcohol abuse increases the risk for pancreatitis. The pattern of alcohol drinking may impact its effect. We tested a hypothesis that chronic ethanol consumption in combination with binge exposure imposes more severe damage to the pancreas. C57BL/6 mice were divided into four groups: control, chronic ethanol exposure, binge ethanol exposure and chronic plus binge ethanol exposure. For the control group, mice were fed with a liquid diet for two weeks. For the chronic ethanol exposure group, mice were fed with a liquid diet containing 5% ethanol for two weeks. In the binge ethanol exposure group, mice were treated with ethanol by gavage (5 g/kg, 25% ethanol w/v) daily for 3 days. For the chronic plus binge exposure group, mice were fed with a liquid diet containing 5% ethanol for two weeks and exposed to ethanol by gavage during the last 3 days. Chronic and binge exposure alone caused minimal pancreatic injury. However, chronic plus binge ethanol exposure induced significant apoptotic cell death. Chronic plus binge ethanol exposure altered the levels of alpha-amylase, glucose and insulin. Chronic plus binge ethanol exposure caused pancreatic inflammation which was shown by the macrophages infiltration and the increase of cytokines and chemokines. Chronic plus binge ethanol exposure increased the expression of ADH1 and CYP2E1. It also induced endoplasmic reticulum stress which was demonstrated by the unfolded protein response. In addition, chronic plus binge ethanol exposure increased protein oxidation and lipid peroxidation, indicating oxidative stress. Therefore, chronic plus binge ethanol exposure is more detrimental to the pancreas. - Highlights: • Chronic plus binge alcohol drinking causes more pancreatic injury. • Chronic plus binge alcohol drinking induces more pancreatic inflammation. • Chronic plus binge alcohol causes more endoplasmic reticulum stress and oxidative stress.

Risk management of exposure to chemicals under operational conditions

NARCIS (Netherlands)

Langenberg, J.P.

2007-01-01

The HFM panel has decided to install an Exploratory Team, ET-078, which should advise whether or not a Technical Group (TG) should be established on the subject of risk management of exposure to chemicals under operational conditions. This paper described the context and approach of ET-078.

The Role of Drinking Severity on Sex Risk Behavior and HIV Exposure among Illicit Drug Users

Science.gov (United States)

Scherer, Michael; Trenz, Rebecca; Harrell, Paul; Mauro, Pia; Latimer, William

2015-01-01

Objectives The current study examined how drinking severity among injection and non-injection drug users is associated with sex risk behaviors and risk of HIV exposure. Methods The study is a secondary analysis of an investigation of risk factors among drug users in Baltimore known as the NEURO-HIV Epidemiologic Study. Participants (N = 557) completed an interview, self-reported 30-day alcohol use, lifetime injection and non-injection drug use, and provided blood samples to screen for HIV. Participants were grouped into one of three drinking severity conditions: Abstinent (no reported alcohol use in prior 30-days), Moderate Alcohol Use (≤30 drinks for females, or ≤ 60 drinks for males), or Problematic Alcohol Use (>30 drinks for females, or >60 drinks for males). Drinking severity groups were significantly different on lifetime injection drug use, heroin injection, snorting/sniffing cocaine, and smoking crack. Results Logistic regression analyses found problematic alcohol users to be more likely than alcohol abstainers to inject drugs before or during sex (AOR = 5.78; 95% CI = 2.07-16.10), and more likely than moderate alcohol users to use alcohol before/during sex (AOR = 4.96; 95% CI = 2.09-11.81), inject drugs before/during sex (AOR = 2.96; 95% CI = 1.29-6.80) and to be HIV+ among Black participants (AOR = 2.72; 95% CI = 1.14-6.49). Conclusions These results outline the necessity for research and clinical intervention among this population to reduce sex risk behaviors and potential HIV exposure, while highlighting the need to examine drinking severity as a predictor of sex risk behaviors. PMID:23617865

[Some aspects of animal-to-human approximation of low frequency electromagnetic field exposure conditions].

Science.gov (United States)

Vasin, A L

2003-01-01

Appropriateness of representation of a biological object surface as an equipotential surface has been proved for conditions of a quasistatic exposure to EMF of frequencies lower than 1 MHz. The conditions, at which a self capacitance of a biological object is its basic electrical parameter, have been considered. A factor of animal-to-human approximation of low-frequency EMF exposure conditions was estimated on the basis of equal dose loading in biological objects of different geometric sizes.

Evaluation of Image According to Exposure Conditions using Contrast-Detail Phantom for Chest Digital Radiography

Energy Technology Data Exchange (ETDEWEB)

Lee, In Ja [Dept. of Radiologic Tecnology, Dongnam Health College, Suwon (Korea, Republic of); Kim, You Hyun; Kim, Chang Nam [Dept. of Radiological Science, College of Health Science, Korea University, Seoul (Korea, Republic of); Kim, Chang Nam; Lee, Chang Yeob; Park, Kye Yeon [Dept. of Diagnostic Radiology, Korea University Guro Hospital, Seoul (Korea, Republic of)

2009-03-15

To find out proper photographing conditions in the chest DR imaging, the evaluation of images using the C-D phantom was carried out on relationship of identification capability, graininess, and exposure ratio. The conclusions were obtained as follows. 1. The patient's entrance skin Exposure (ESE) was decreased as tube voltage was increased. 2. According to the tube voltage change, the C-D phantom's identification capability of the exposure conditions was most visible at 110 kVp. 3. The identification capability according to the exposure ratio (mAs) change was most visible at 90 kVp for 0.5 times of low exposure ratio and at 110 kVp for 1.5 times. Therefore, it is known that the images were able to be better identified at a high exposure than a low exposure. 4. The graininess according to the exposure ratio at tube voltage of 110 kVp resulted in the best thing at 1.5 times of ratio when the exposure ratio was 1.5 times increased and the tube voltage was changed, the graininess showed the best result at 110 kVp. Therefore, the patient's exposure dose was low when kVp was increased and the adequate kVp was found to be 110. The image was better identified when exposure ratio was 1.5 times compared to 1.0 times. The graininess was also good when the exposure ratio became 1.5 times. The tube voltage was good at 110 kVp. However, once the exposure ratio is increased, the amount of radiation dose that the patients received get increased, so that the exposure condition has to be thoroughly considered.

Evaluation of Image According to Exposure Conditions using Contrast-Detail Phantom for Chest Digital Radiography

International Nuclear Information System (INIS)

Lee, In Ja; Kim, You Hyun; Kim, Chang Nam; Kim, Chang Nam; Lee, Chang Yeob; Park, Kye Yeon

2009-01-01

To find out proper photographing conditions in the chest DR imaging, the evaluation of images using the C-D phantom was carried out on relationship of identification capability, graininess, and exposure ratio. The conclusions were obtained as follows. 1. The patient's entrance skin Exposure (ESE) was decreased as tube voltage was increased. 2. According to the tube voltage change, the C-D phantom's identification capability of the exposure conditions was most visible at 110 kVp. 3. The identification capability according to the exposure ratio (mAs) change was most visible at 90 kVp for 0.5 times of low exposure ratio and at 110 kVp for 1.5 times. Therefore, it is known that the images were able to be better identified at a high exposure than a low exposure. 4. The graininess according to the exposure ratio at tube voltage of 110 kVp resulted in the best thing at 1.5 times of ratio when the exposure ratio was 1.5 times increased and the tube voltage was changed, the graininess showed the best result at 110 kVp. Therefore, the patient's exposure dose was low when kVp was increased and the adequate kVp was found to be 110. The image was better identified when exposure ratio was 1.5 times compared to 1.0 times. The graininess was also good when the exposure ratio became 1.5 times. The tube voltage was good at 110 kVp. However, once the exposure ratio is increased, the amount of radiation dose that the patients received get increased, so that the exposure condition has to be thoroughly considered.

Severe adverse effects related to dermal exposure to a glyphosate-surfactant herbicide

DEFF Research Database (Denmark)

Mariager, T P; Madsen, P V; Ebbehøj, N E

2013-01-01

This is a case of severe chemical burns following prolonged accidental exposure to a glyphosate-surfactant herbicide. The patient developed local swelling, bullae and exuding wounds. Neurological impairment followed affecting finger flexion and sensation with reduced nerve conduction. Imaging rev...

Enhanced Eyeblink Conditioning in Behaviorally Inhibited Individuals is Disrupted by Proactive Interference Following US Alone Pre-exposures.

Science.gov (United States)

Allen, Michael Todd; Miller, Daniel P

2016-01-01

Anxiety vulnerable individuals exhibit enhanced acquisition of conditioned eyeblinks as well as enhanced proactive interference from conditioned stimulus (CS) or unconditioned stimulus (US) alone pre-exposures (Holloway et al., 2012). US alone pre-exposures disrupt subsequent conditioned response (CR) acquisition to CS-US paired trials as compared to context pre-exposure controls. While Holloway et al. (2012) reported enhanced acquisition in high trait anxiety individuals in the context condition, anxiety vulnerability effects were not reported for the US alone pre-exposure group. It appears from the published data that there were no differences between high and low anxiety individuals in the US alone condition. In the work reported here, we sought to extend the findings of enhanced proactive interference with US alone pre-exposures to determine if the enhanced conditioning was disrupted by proactive interference procedures. We also were interested in the spontaneous eyeblinks during the pre-exposure phase of training. We categorized individuals as anxiety vulnerability or non-vulnerable individuals based scores on the Adult Measure of Behavioral Inhibition (AMBI). Sixty-six participants received 60 trials consisting of 30 US alone or context alone pre-exposures followed by 30 CS-US trials. US alone pre-exposures not only disrupted CR acquisition overall, but behaviorally inhibited (BI) individuals exhibited enhanced proactive interference as compared to non-inhibited (NI) individuals. In addition, US alone pre-exposures disrupted the enhanced acquisition observed in BI individuals as compared to NI individuals following context alone pre-exposures. Differences were also found in rates of spontaneous eyeblinks between BI and NI individuals during context pre-exposure. Our findings will be discussed in the light of the neural substrates of eyeblink conditioning as well as possible factors such as hypervigilance in the amygdala and hippocampal systems, and possible

Severity and exposure associated to tsunami actions in urban waterfronts. The case of Lisbon, Portugal.

Science.gov (United States)

Conde, Daniel; Telhado, Maria J.; Viana Baptista, Maria A.; Antunes, Carlos M.; Ferreira, Rui M. L.

2014-05-01

The Tagus estuary is recognized as an exposed location to tsunami occurrences, given its proximity to tsunamigenic faults such as the Marquês de Pombal and the Horseshoe fault system. Lisbon, bordered by the Tagus estuary, is a critical point of Portugal's tsunami hazard map, having been affected by several tsunamis (Baptista and Miranda, 2009) including the notorious event of November 1st 1755, the last major natural disaster known to have inflicted massive destruction in Portugal. The main objective of this work, a joint initiative of CEHIDRO (IST - Universidade de Lisboa) and the Municipal Civil Protection Services of Lisbon, is to contribute to the quantification of severity and exposure of Lisbon waterfront to tsunami events. For that purpose, the propagation of a tsunami similar to that of the 1st November of 1755 in the Tagus estuary was numerically simulated. Several scenarios were considered, articulating the influence of tidal (low and high tides), atmospheric (increase in water level due to storm surges) and hydrological (flow discharge in Tagus river) conditions. Different initial and boundary conditions were defined for each modelling scenario but the magnitude of the tsunami remained what is believed to be an exceptional event. The extent of the inundation and relevant hydrodynamic quantities were registered for all scenarios. The employed simulation tool - STAV-2D - was developed at CEHIDRO (IST) and is based on a 2DH spatial (Eulerian) shallow-flow approach suited to complex and dynamic bottom boundaries. The discretization technique relies on a finite-volume scheme, based on a flux-splitting technique incorporating a reviewed version of the Roe Riemann solver (Canelas et al. 2013, Conde et al. 2013). STAV-2D features conservation equations for the finer solid phase of the flow and also a Lagrangian model for the advection of larger debris elements. The urban meshwork was thoroughly discretized with a mesh finer than average street width. This fine

Study some mechanical properties of self-compacting concrete with nano silica under severe saline environment conditions

Directory of Open Access Journals (Sweden)

Habeeb Ghalib

2018-01-01

Full Text Available The main aim of this research is to evaluate the performance of Nano silica self-compacting concrete which is subjected to severe saline conditions that contain sulfates and chlorides at concentrations similar to those existing in the soils and ground water of the middle and southern parts of Iraq. For this purpose, ordinary and sulfate resistant Portland cement without and with 3% Nano silica addition by weight of cementitious materials were used. Splitting tensile strength, flexural strength, static modulus of elasticity and ultrasonic pulse velocity were investigated for all exposure conditions and all types of mixes of self-compacting concrete at ages of 28, 60, 90, 120 and 180 days. Test results revealed that the inclusion of Nano Silica in concrete mixes improved clearly the mechanical properties of self-compacting concrete compared with reference concrete.

Evaluation of several methods for assessing the effects of occupational exposure to radiation

International Nuclear Information System (INIS)

Gilbert, E.S.

1980-05-01

The evaluation of health effects in populations occupationally exposed to low-level ionizing radiation is a matter of considerable current controversy. The analysis of data on such exposures presents a variety of problems resulting from the time dependent nature of the exposure data, certain selective biases found in working populations, and particularly limits imposed by the size of the populations, and the magnitudes of exposures received. In this paper, several methods of analysis are presented and evaluated using data from the Hanford plant for illustration. Questions of interest include whether or not to utilize an external control, and how to handle the highly skewed exposure data most effectively. Expressions for the power of various procedures are used not only to compare methods but also to evaluate the potential for detecting effects in occupationally exposed populations

Neuropsychological alterations in mercury intoxication persist several years after exposure

Directory of Open Access Journals (Sweden)

Elaine Cristina Zachi

Full Text Available Abstract Elemental mercury is a liquid toxic metal widely used in industry. Occupational exposure occurs mainly via inhalation. Previously, neuropsychological assessment detected deficits in former workers of a fluorescent lamp plant who had been exposed to elemental mercury vapor and were away from exposure for several years at the time of examination. Objectives: The purpose of this work was to reexamine these functions after 18 months in order to evaluate their progression. Methods: Thirteen participants completed tests of attention, inhibitory control, verbal/visual memory, psychomotor speed, verbal fluency, visuomotor ability, executive function, semantic knowledge, and depression and anxiety inventories on 2 separate occasions. Results: At baseline, the former workers indicated slower psychomotor and information processing speed, verbal spontaneous recall memory impairment, and increased depression and anxiety symptoms compared to controls (P<0.05. Paired comparisons of neuropsychological functioning within the exposed group at baseline and 1.5 years later showed poorer immediate memory performance (P<0.05. There were no differences on other measures. Conclusions: Although the literature show signs of recovery of functions, the neuropsychological effects related to mercury exposure are found to persist for many years.

Community violence exposure and severe posttraumatic stress in suburban American youth: risk and protective factors.

Science.gov (United States)

Löfving-Gupta, Sandra; Lindblad, Frank; Stickley, Andrew; Schwab-Stone, Mary; Ruchkin, Vladislav

2015-04-01

The psychological effects of community violence exposure among inner-city youth are severe, yet little is known about its prevalence and moderators among suburban middle-class youth. This study aimed to assess the prevalence of community violence exposure among suburban American youth, to examine associated posttraumatic stress and to evaluate factors related to severe vs. less severe posttraumatic stress, such as co-existing internalizing and externalizing problems, as well as the effects of teacher support, parental warmth and support, perceived neighborhood safety and conventional involvement in this context. Data were collected from 780 suburban, predominantly Caucasian middle-class high-school adolescents in the Northeastern US during the Social and Health Assessment (SAHA) study. A substantial number of suburban youth were exposed to community violence and 24% of those victimized by community violence developed severe posttraumatic stress. Depressive symptoms were strongly associated with higher levels and perceived teacher support with lower levels of posttraumatic stress. Similar to urban youth, youth living in suburban areas in North American settings may be affected by community violence. A substantial proportion of these youth reports severe posttraumatic stress and high levels of comorbid depressive symptoms. Teacher support may have a protective effect against severe posttraumatic stress and thus needs to be further assessed as a potential factor that can be used to mitigate the detrimental effects of violence exposure.

Higher risk of offspring schizophrenia following antenatal maternal exposure to severe adverse life events

DEFF Research Database (Denmark)

Khashan, Ali; Abel, Kathryn; McNamee, R.

2008-01-01

CONTEXT: Most societies believe that a mother's psychological state can influence her unborn baby. Severe adverse life events during pregnancy have been consistently associated with an elevated risk of low birth weight and prematurity. Such events during the first trimester have also been...... associated with risk of congenital malformations. OBJECTIVE: To assess the effect in offspring of antenatal maternal exposure to an objective measure of stress on risk of adverse neurodevelopment, specifically schizophrenia. We hypothesized that the strongest relationship would be to maternal exposures...... not linked with a higher risk of schizophrenia. CONCLUSIONS: Our population-based study suggests that severe stress to a mother during the first trimester may alter the risk of schizophrenia in offspring. This finding is consistent with ecological evidence from whole populations exposed to severe stressors...

Cannabinoids prevent the differential long-term effects of exposure to severe stress on hippocampal- and amygdala-dependent memory and plasticity.

Science.gov (United States)

Shoshan, Noa; Segev, Amir; Abush, Hila; Mizrachi Zer-Aviv, Tomer; Akirav, Irit

2017-10-01

Exposure to excessive or uncontrolled stress is a major factor associated with various diseases including posttraumatic stress disorder (PTSD). The consequences of exposure to trauma are affected not only by aspects of the event itself, but also by the frequency and severity of trauma reminders. It was suggested that in PTSD, hippocampal-dependent memory is compromised while amygdala-dependent memory is strengthened. Several lines of evidence support the role of the endocannabinoid (eCB) system as a modulator of the stress response. In this study we aimed to examine cannabinoids modulation of the long-term effects (i.e., 1 month) of exposure to a traumatic event on memory and plasticity in the hippocampus and amygdala. Following exposure to the shock and reminders model of PTSD in an inhibitory avoidance light-dark apparatus rats demonstrated: (i) enhanced fear retrieval and impaired inhibitory extinction (Ext), (ii) no long-term potentiation (LTP) in the CA1, (iii) impaired hippocampal-dependent short-term memory in the object location task, (iv) enhanced LTP in the amygdala, and (v) enhanced amygdala-dependent conditioned taste aversion memory. The cannabinoid CB1/2 receptor agonist WIN55-212,2 (0.5mg/kg, i.p.) and the fatty acid amide hydrolase (FAAH) inhibitor URB597 (0.3mg/kg, i.p.), administered 2 hr after shock exposure prevented these opposing effects on hippocampal- and amygdala-dependent processes. Moreover, the effects of WIN55-212,2 and URB597 on Ext and acoustic startle were prevented by co-administration of a low dose of the CB1 receptor antagonist AM251 (0.5mg/kg, i.p.), suggesting that the preventing effects of both drugs are mediated by CB1 receptors. Exposure to shock and reminders increased CB1 receptor levels in the CA1 and basolateral amygdala 1 month after shock exposure and this increase was also prevented by administering WIN55-212,2 or URB597. Taken together, these findings suggest the involvement of the eCB system, and specifically CB1

[Circadian blood pressure variation under several pathophysiological conditions including secondary hypertension].

Science.gov (United States)

Imai, Yutaka; Hosaka, Miki; Satoh, Michihiro

2014-08-01

Abnormality of circadian blood pressure (BP) variation, i.e. non-dipper, riser, nocturnal hypertension etc, is brought by several pathophysiological conditions especially by secondary hypertension. These pathophysiological conditions are classified into several categories, i.e. disturbance of autonomic nervous system, metabolic disorder, endocrine disorder, disorder of Na and water excretion (e.g. sodium sensitivity), severe target organ damage and ischemia, cardiovascular complications and drug induced hypertension. Each pathophysiological condition which brings disturbance of circadian BP variation is included in several categories, e.g. diabetes mellitus is included in metabolic disorder, autonomic imbalance, sodium sensitivity and endocrine disorder. However, it seems that unified principle of the genesis of disturbance of circadian BP variation in many pathophysiological conditions is autonomic imbalance. Thus, it is concluded that disturbance of circadian BP variation is not purposive biological behavior but the result of autonomic imbalance which looks as if compensatory reaction such as exaggerated Na-water excretion during night in patient with Na-water retention who reveals disturbed circadian BP variation.

Physiologic changes associated with violence and abuse exposure: an examination of related medical conditions.

Science.gov (United States)

Keeshin, Brooks R; Cronholm, Peter F; Strawn, Jeffrey R

2012-01-01

Although the extant evidence is replete with data supporting linkages between exposure to violence or abuse and the subsequent development of medical illnesses, the underlying mechanisms of these relationships are poorly defined and understood. Physiologic changes occurring in violence- or abuse-exposed individuals point to potentially common biological pathways connecting traumatic exposures with medical outcomes. Herein, the evidence describing the long-term physiologic changes in abuse- and violence-exposed populations and associated medical illnesses are reviewed. Current data support that (a) specific neurobiochemical changes are associated with exposure to violence and abuse; (b) several biological pathways have the potential to lead to the development of future illness; and (c) common physiologic mechanisms may moderate the severity, phenomenology, or clinical course of medical illnesses in individuals with histories of exposure to violence or abuse. Importantly, additional work is needed to advance our emerging understanding of the biological mechanisms connecting exposure to violence and abuse and negative health outcomes.

Modified expression of several sperm proteins after chronic exposure to the antiandrogenic compound vinclozolin.

Science.gov (United States)

Auger, Jacques; Eustache, Florence; Maceiras, Paula; Broussard, Cédric; Chafey, Philippe; Lesaffre, Corinne; Vaiman, Daniel; Camoin, Luc; Auer, Jana

2010-10-01

Little is known about the molecular impact of in vivo exposure to endocrine disruptors (EDs) on sperm structures and functions. We recently reported that the lifelong exposure of rats to the antiandrogenic compound vinclozolin results in low epididymal weight, changes in sperm kinematic parameters, and immature sperm chromatin condensation, together with the impairment of several fertility end points. These results led us to focus specifically on possible molecular abnormalities in sperm. Sperm samples were recovered from the frozen epididymides of rats exposed during the previous study. The proteins present in the samples from six exposed and six control rats were analyzed in pairs, by two-dimensional fluorescence difference gel electrophoresis, to investigate possible exposure-induced changes to sperm protein profiles. Twelve proteins, from the 380 matched spots observed in at least five gels, were present in larger or smaller amounts after vinclozolin exposure. These proteins were identified by mass spectrometry, and several are known to play a crucial role in the sperm fertilizing ability, among which, two mitochondrial enzymes, malate dehydrogenase 2 and aldehyde dehydrogenase (both of which were present in smaller amounts after treatment) and A-kinase anchor protein 4 (larger amounts of precursor after treatment). Finally, Ingenuity Pathway Analysis revealed highly significant interactions between proteins over- and underexpressed after treatment. This is the first study to show an association between in vivo exposure to an ED and changes to the sperm protein profile. These modifications may be at least partly responsible for the reproductive abnormalities and impaired fertility recently reported in this rat model of vinclozolin exposure.

Exposure to Severe Urban Air Pollution Influences Cognitive Outcomes, Brain Volume and Systemic Inflammation in Clinically Healthy Children

Science.gov (United States)

Calderon-Garciduenas, Lilian; Engle, Randall; Mora-Tiscareno, Antonieta; Styner, Martin; Gomez-Garza, Gilberto; Zhu, Hongtu; Jewells, Valerie; Torres-Jardon, Ricardo; Romero, Lina; Monroy-Acosta, Maria E.; Bryant, Christopher; Gonzalez-Gonzalez, Luis Oscar; Medina-Cortina, Humberto; D'Angiulli, Amedeo

2011-01-01

Exposure to severe air pollution produces neuroinflammation and structural brain alterations in children. We tested whether patterns of brain growth, cognitive deficits and white matter hyperintensities (WMH) are associated with exposures to severe air pollution. Baseline and 1 year follow-up measurements of global and regional brain MRI volumes,…

Enhanced eyeblink conditioning in behaviorally inhibited individuals is disrupted by proactive interference following US alone pre-exposures.

Directory of Open Access Journals (Sweden)

Michael Todd Allen

2016-03-01

Full Text Available Anxiety vulnerable individuals exhibit enhanced acquisition of conditioned eyeblinks as well as enhanced proactive interference from CS or US alone pre-exposures (Holloway et al., 2012. US alone pre-exposures disrupt subsequent CR acquisition to CS-US paired trials as compared to context pre-exposure controls. While Holloway et al., (2012 reported enhanced acquisition in high trait anxiety individuals in the context condition, anxiety vulnerability effects were not reported for the US alone pre-exposure group. It appears from the published data that there were no differences between high and low anxiety individuals in the US alone condition. In the work reported here, we sought to extend the findings of enhanced proactive interference with US alone pre-exposures to determine if the enhanced conditioning was disrupted by proactive interference procedures. We also were interested in the spontaneous eyeblinks during the pre-exposure phase of training. We categorized individuals as anxiety vulnerability or non-vulnerable individuals based scores on the Adult Measure of Behavioural Inhibition (AMBI. Sixty six participants received 60 trials consisting of 30 US alone or context alone pre-exposures followed by 30 CS-US trials. US alone pre-exposures not only disrupted CR acquisition overall, but behaviorally inhibited (BI individuals exhibited enhanced proactive interference as compared to non-inhibited (NI individuals. In addition, US alone pre-exposures disrupted the enhanced acquisition observed in BI individuals as compared to NI individuals following context alone pre-exposures. Differences were also found in rates of spontaneous eyeblinks between BI and NI individuals during context pre-exposure. Our findings will be discussed in the light of the neural substrates of eyeblink conditioning as well as possible factors such as hypervigilance in the amygdala and hippocampal systems, and possible learned helplessness. Applications of these findings of

Sex and Adolescent Ethanol Exposure Influence Pavlovian Conditioned Approach.

Science.gov (United States)

Madayag, Aric C; Stringfield, Sierra J; Reissner, Kathryn J; Boettiger, Charlotte A; Robinson, Donita L

2017-04-01

Alcohol use among adolescents is widespread and a growing concern due to long-term behavioral deficits, including altered Pavlovian behavior, that potentially contribute to addiction vulnerability. We tested the hypothesis that adolescent intermittent ethanol (AIE) exposure alters Pavlovian behavior in males and females as measured by a shift from goal-tracking to sign-tracking. Additionally, we investigated GLT-1, an astrocytic glutamate transporter, as a potential contributor to a sign-tracking phenotype. Male and female Sprague-Dawley rats were exposed to AIE (5 g/kg, intragastric) or water intermittently 2 days on and 2 days off from postnatal day (P) 25 to 54. Around P70, animals began 20 daily sessions of Pavlovian conditioned approach (PCA), where they learned that a cue predicted noncontingent reward delivery. Lever pressing indicated interaction with the cue, or sign-tracking, and receptacle entries indicated approach to the reward delivery location, or goal-tracking. To test for effects of AIE on nucleus accumbens (NAcc) excitatory signaling, we isolated membrane subfractions and measured protein levels of the glutamate transporter GLT-1 after animals completed behavior as a measure of glutamate homeostasis. Females exhibited elevated sign-tracking compared to males with significantly more lever presses, faster latency to first lever press, and greater probability to lever press in a trial. AIE significantly increased lever pressing while blunting goal-tracking, as indicated by fewer cue-evoked receptacle entries, slower latency to receptacle entry, and lower probability to enter the receptacle in a trial. No significant sex-by-exposure interactions were observed in sign- or goal-tracking metrics. Moreover, we found no significant effects of sex or exposure on membrane GLT-1 expression in the NAcc. Females exhibited enhanced sign-tracking compared to males, while AIE decreased goal-tracking compared to control exposure. Our findings support the

Exploration of exposure conditions with a novel wireless detector for bedside digital radiography

Science.gov (United States)

Bosmans, Hilde; Nens, Joris; Delzenne, Louis; Marshall, Nicholas; Pauwels, Herman; De Wever, Walter; Oyen, Raymond

2012-03-01

We propose, apply and validate an optimization scheme for a new wireless CsI based DR detector in combination with a regular mobile X-ray system for bedside imaging applications. Three different grids were tested in this combination. Signal-difference-to-noise was investigated in two ways, using a 1mm Cu piece in combination with different thicknesses of PMMA and by means of the CDRAD phantom using 10 images per condition and an automated evaluation method. A Figure of Merit (FOM), namely SDNR2/Imparted Energy, was calculated for a large range of exposure conditions, without and with grid in place. Misalignment of the grids was evaluated via the same FOMs. This optimization study was validated with comparative X-ray acquisitions performed on dead bodies. An experienced radiologist scored the quality of several specific aspects for all these exposures. Signal difference to noise ratios measured with the Cu method correlated well with the threshold contrasts from the CDRAD analysis (R2 > 0.9). The analysis showed optimal FOM with detector air kerma rates as typically used in clinical practice. Lower tube voltages provide higher FOM than the higher values but their practical use depends on the limitations of X-ray tubes, linked to patient motion artefacts. The use of high resolution grids should be encouraged, as the FOM increases with 47% at 75kV. These scores from the Visual grading study confirmed the results obtained with the FOM. The switch to (wireless) DR technology for bedside imaging could benefit from devices to improve grid positioning or any scatter reduction technique.

[Occupational differences in exposure to hazardous work conditions].

Science.gov (United States)

Marinacci, Chiara; d'Errico, A; Cardano, M; Perini, F; Costa, G

2005-01-01

Few studies have been aimed at describing organizational and psychosocial conditions of the Italian workforce by occupational group, and they have been mainly conducted within specific occupations. The present study aimed at identifying specific groups of occupations which have unfavourable profiles from the point of view of exposure to specific organizational factors and psychosocial risks, and to physical, chemical and ergonomic risks, and analyzing their distribution by worker age. The analysis was conducted on a sample of 4,195 workers in the Piedmont Region who were members of the CGIL Trade Union (Italian General Confederation of Labour), who answered a self-administered questionnaire in 2000, aimed at assessing chemical, physical, and ergonomic risks, accidents, and psychosocial factors connected with work organization and work tasks. Psychosocial risks were assessed via three scales aimed at measuring the degree of control, psychophysical demands, and worker satisfaction. The proportion of workers exposed to the above mentioned risks was analysed according to occupational group. This group was then compared with all other groups taken together, according to prevalence of high strain condition (combination of high demand and low control) and HSUR condition (High Strain Unfairly Rewarded; combination of high strain and low satisfaction). Among males aged 25-44 years, restricted to the occupation groups with more than ten workers in high strain condition, significantly higher proportions of stress were observed in leather workers and shoemakers, paper factory workers, rubber workers, crane and bridge crane operators, plastic workers, painters, transport drivers and carpenters. For many of these groups, excesses were confirmed for the HSUR condition. Among subjects aged over 44 years, a higher risk for high strain was confirmed in rubber workers, transport drivers and carpenters. In addition, machine tool operators, assembly line and mechanical workers in this

Identification of severe wind conditions using a Reynolds Averaged Navier-Stokes solver

International Nuclear Information System (INIS)

Soerensen, N N; Bechmann, A; Johansen, J; Myllerup, L; Botha, P; Vinther, S; Nielsen, B S

2007-01-01

The present paper describes the application of a Navier-Stokes solver to predict the presence of severe flow conditions in complex terrain, capturing conditions that may be critical to the siting of wind turbines in the terrain. First it is documented that the flow solver is capable of predicting the flow in the complex terrain by comparing with measurements from two meteorology masts. Next, it is illustrated how levels of turbulent kinetic energy can be used to easily identify areas with severe flow conditions, relying on a high correlation between high turbulence intensity and severe flow conditions, in the form of high wind shear and directional shear which may seriously lower the lifetime of a wind turbine

A NOVEL EFFECT OF DIOXIN: EXPOSURE DURING PREGNANCY SEVERELY IMPAIRS MAMMARY GLAND DIFFERENTIATION

Science.gov (United States)

A novel effect of dioxin: Exposure during pregnancy severely impairs mammary gland differentiation.Beth A. Vorderstrasse1, Suzanne E. Fenton2, Andrea A. Bohn3, Jennifer A. Cundiff1, and B. Paige Lawrence1,3,4 1Department of Pharmaceutical Sciences, Washington State Universi...

Full-length fuel rod behavior under severe accident conditions

International Nuclear Information System (INIS)

Lombardo, N.J.; Lanning, D.D.; Panisko, F.E.

1992-12-01

This document presents an assessment of the severe accident phenomena observed from four Full-Length High-Temperature (FLHT) tests that were performed by the Pacific Northwest Laboratory (PNL) in the National Research Universal (NRU) reactor at Chalk River, Ontario, Canada. These tests were conducted for the US Nuclear Regulatory Commission (NRC) as part of the Severe Accident Research Program. The objectives of the test were to simulate conditions and provide information on the behavior of full-length fuel rods during hypothetical, small-break, loss-of-coolant severe accidents, in commercial light water reactors

Comparison of ESD and major organ absorbed doses of 5 year old standard guidekines and clinical exposure conditions

Energy Technology Data Exchange (ETDEWEB)

Kang, A Ram; Ahn, Sung Min [Dept. of Radiological Science, The Graduate School, Gachon University, Incheon (Korea, Republic of); Lee, In Ja [Dept. of Radiologic technology, Dongnam health University, Suwon (Korea, Republic of)

2017-09-15

Pediatrics are more sensibility to radiation than adults and because they are organs that are not completely grown, they have a life expectancy that can be adversely affected by exposure. Therefore, the management of exposure dose is more important than the case of adult. The purpose of this study was to determine the suitability of the 10 year old phantom for the 5 year old pediatric's recommendation and the incident surface dose, and to measure the organ absorbed dose. This study is compared the organ absorbed dose and the entrance surface dose in the clinical conditions at 5 and 10 years old pediatric. Clinical 5 year old condition was slightly higher than recommendation condition and 10 year old condition was very high. In addition, recommendation condition ESD was found to be 43% higher than the ESD of the 5 year old group and the ESD of the 10 year old group was 126% higher than that of the 5 year old group. The recommended ESD at 5 years old and the ESD according to clinical imaging conditions were 31.6%. There was no significant difference between the 5 year old recommended exposure conditions and the organ absorbed dose due to clinical exposure conditions, but there was a large difference between the Chest and Pelvic. However, it was found that there was a remarkable difference when comparing the organ absorbed dose by 10 year clinical exposure conditions. Therefore, more detailed standard exposure dose for the recommended dose of pediatric should be studied.

Comparison of ESD and major organ absorbed doses of 5 year old standard guidekines and clinical exposure conditions

International Nuclear Information System (INIS)

Kang, A Ram; Ahn, Sung Min; Lee, In Ja

2017-01-01

Pediatrics are more sensibility to radiation than adults and because they are organs that are not completely grown, they have a life expectancy that can be adversely affected by exposure. Therefore, the management of exposure dose is more important than the case of adult. The purpose of this study was to determine the suitability of the 10 year old phantom for the 5 year old pediatric's recommendation and the incident surface dose, and to measure the organ absorbed dose. This study is compared the organ absorbed dose and the entrance surface dose in the clinical conditions at 5 and 10 years old pediatric. Clinical 5 year old condition was slightly higher than recommendation condition and 10 year old condition was very high. In addition, recommendation condition ESD was found to be 43% higher than the ESD of the 5 year old group and the ESD of the 10 year old group was 126% higher than that of the 5 year old group. The recommended ESD at 5 years old and the ESD according to clinical imaging conditions were 31.6%. There was no significant difference between the 5 year old recommended exposure conditions and the organ absorbed dose due to clinical exposure conditions, but there was a large difference between the Chest and Pelvic. However, it was found that there was a remarkable difference when comparing the organ absorbed dose by 10 year clinical exposure conditions. Therefore, more detailed standard exposure dose for the recommended dose of pediatric should be studied

Consequences of adolescent ethanol exposure in male Sprague-Dawley rats on fear conditioning and extinction in adulthood

Science.gov (United States)

Broadwater, Margaret A.

Some evidence suggests that adolescents are more vulnerable than adults to alcohol-induced cognitive deficits and that these deficits may persist into adulthood. Five experiments were conducted to assess long-term consequences of ethanol exposure on tone and context Pavlovian fear conditioning in male Sprague-Dawley rats. Experiment 1 examined age-related differences in sensitivity to ethanol-induced disruptions of fear conditioning to a pre-conditioning ethanol challenge. Experiments 2 examined fear conditioning 22 days after early-mid adolescent (P28-48) or adult (P70-90) exposure to 4 g/kg i.g. ethanol or water given every other day (total of 11 exposures). In Experiment 3, mid-late adolescents (P35-55) were exposed in the same manner to assess whether timing of ethanol exposure within the adolescent period would differentially affect later fear conditioning. Experiment 4 assessed the influence of prior adolescent or adult ethanol exposure on the disrupting effects of a pre-conditioning ethanol challenge. In Experiment 5, neurogenesis (doublecortin---DCX) and cholinergic (choline acetyltransferase---ChAT) markers were measured to assess potential long-term ethanol-induced changes in neural mechanisms important for learning and memory. Results indicated that the long-lasting behavioral effects of ethanol exposure varied depending on exposure age, with early-mid adolescent exposed animals showing attenuated context fear retention (a relatively hippocampal-dependent task), whereas mid-late adolescent and adult exposed animals showed slower context extinction (thought to be reliant on the mPFC). Early-mid adolescent ethanol-exposed animals also had significantly less DCX and ChAT expression than their water-exposed counterparts, possibly contributing to deficits in context fear. Tone fear was not influenced by prior ethanol exposure at any age. In terms of age differences in ethanol sensitivity, adolescents were less sensitive than adults to ethanol

Embryonic Methamphetamine Exposure Inhibits Methamphetamine Cue Conditioning and Reduces Dopamine Concentrations in Adult N2 Caenorhabditis elegans.

Science.gov (United States)

Katner, Simon N; Neal-Beliveau, Bethany S; Engleman, Eric A

2016-01-01

Methamphetamine (MAP) addiction is substantially prevalent in today's society, resulting in thousands of deaths and costing billions of dollars annually. Despite the potential deleterious consequences, few studies have examined the long-term effects of embryonic MAP exposure. Using the invertebrate nematode Caenorhabditis elegans allows for a controlled analysis of behavioral and neurochemical changes due to early developmental drug exposure. The objective of the current study was to determine the long-term behavioral and neurochemical effects of embryonic exposure to MAP in C. elegans. In addition, we sought to improve our conditioning and testing procedures by utilizing liquid filtration, as opposed to agar, and smaller, 6-well testing plates to increase throughput. Wild-type N2 C. elegans were embryonically exposed to 50 μM MAP. Using classical conditioning, adult-stage C. elegans were conditioned to MAP (17 and 500 μM) in the presence of either sodium ions (Na+) or chloride ions (Cl-) as conditioned stimuli (CS+/CS-). Following conditioning, a preference test was performed by placing worms in 6-well test plates spotted with the CS+ and CS- at opposite ends of each well. A preference index was determined by counting the number of worms in the CS+ target zone divided by the total number of worms in the CS+ and CS- target zones. A food conditioning experiment was also performed in order to determine whether embryonic MAP exposure affected food conditioning behavior. For the neurochemical experiments, adult worms that were embryonically exposed to MAP were analyzed for dopamine (DA) content using high-performance liquid chromatography. The liquid filtration conditioning procedure employed here in combination with the use of 6-well test plates significantly decreased the time required to perform these experiments and ultimately increased throughput. The MAP conditioning data found that pairing an ion with MAP at 17 or 500 μM significantly increased the preference

The Conditional Scope of Selective Exposure to Political Television Media, 1996-2012

DEFF Research Database (Denmark)

Robison, Joshua; Leeper, Thomas

Pew Research Center data from 1996 to 2012, we document that exposure to ideological or partisan media is heavily conditioned by time, audience size, and individuals’ interest in national politics. Selective exposure seems to be limited to partisans with a high interest in politics viewing a handful......A considerable amount of research documents an ideological or partisan bias in media exposure: liberals and Democrats are more likely to be exposed to liberal-leaning media while conservatives and Republicans are more likely to be exposed to conservative-leaning media. Much of this research......, however, was conducted in the mid-2000’s, a politically contentious period in American politics. We argue that there are many reasons to expect this political context to be a period that encouraged high degrees of selective exposure, especially among partisans and those with high political interest. Using...

Explicit formula of finite difference method to estimate human peripheral tissue temperatures during exposure to severe cold stress.

Science.gov (United States)

Khanday, M A; Hussain, Fida

2015-02-01

During cold exposure, peripheral tissues undergo vasoconstriction to minimize heat loss to preserve the maintenance of a normal core temperature. However, vasoconstricted tissues exposed to cold temperatures are susceptible to freezing and frostbite-related tissue damage. Therefore, it is imperative to establish a mathematical model for the estimation of tissue necrosis due to cold stress. To this end, an explicit formula of finite difference method has been used to obtain the solution of Pennes' bio-heat equation with appropriate boundary conditions to estimate the temperature profiles of dermal and subdermal layers when exposed to severe cold temperatures. The discrete values of nodal temperature were calculated at the interfaces of skin and subcutaneous tissues with respect to the atmospheric temperatures of 25 °C, 20 °C, 15 °C, 5 °C, -5 °C and -10 °C. The results obtained were used to identify the scenarios under which various degrees of frostbite occur on the surface of skin as well as the dermal and subdermal areas. The explicit formula of finite difference method proposed in this model provides more accurate predictions as compared to other numerical methods. This model of predicting tissue temperatures provides researchers with a more accurate prediction of peripheral tissue temperature and, hence, the susceptibility to frostbite during severe cold exposure. Copyright © 2014 Elsevier Ltd. All rights reserved.

CYP polymorphisms and pathological conditions related to chronic exposure to organochlorine pesticides

Directory of Open Access Journals (Sweden)

Anca Oana Docea

Full Text Available The association between genetic variations in the cytochrome P450 (CYP family genes and pathological conditions related to long-term exposure to organochlorine compounds (OCs deserves further elucidation. OCs are persistent organic pollutants with bioaccumulative and lipophilic characteristics. They can act as endocrine disruptors and perturb cellular mechanisms. Prolonged exposure to OCs has been associated with different pathological manifestations. CYP genes are responsible for transcribing enzymes essential in xenobiotic metabolism. Therefore, polymorphisms in these genetic sequences a. alter the metabolic pathways, b. induce false cellular responses, and c. may provoke pathological conditions. The main aim of this review is to define the interaction between parameters a, b and c at a mechanistic/molecular level, with references in clinical cases. Keywords: Organochlorine compounds, Cytochrome P450, Genetic polymorphisms, Pathogenesis, Environmental pollutants

Assessment of Equipment Capability to Perform Reliably under Severe Accident Conditions

International Nuclear Information System (INIS)

2017-07-01

The experience from the last 40 years has shown that severe accidents can subject electrical and instrumentation and control (I&C) equipment to environmental conditions exceeding the equipment’s original design basis assumptions. Severe accident conditions can then cause rapid degradation or damage to various degrees up to complete failure of such equipment. This publication provides the technical basis to consider when assessing the capability of electrical and I&C equipment to perform reliably during a severe accident. It provides examples of calculation tools to determine the environmental parameters as well as examples and methods that Member States can apply to assess equipment reliability.

Re-exposure to low osmolar iodinated contrast media in patients with prior moderate-to-severe hypersensitivity reactions: A multicentre retrospective cohort study.

Science.gov (United States)

Park, Hye Jung; Park, Jung-Won; Yang, Min-Suk; Kim, Mi-Yeong; Kim, Sae-Hoon; Jang, Gwang Cheon; Nam, Young-Hee; Kim, Gun-Woo; Kim, Sujeong; Park, Hye-Kyung; Jung, Jae-Woo; Park, Jong-Sook; Kang, Hye-Ryun

2017-07-01

To evaluate the outcomes of re-exposure to low-osmolar iodinated contrast medium (LOCM) in patients with a history of moderate-to-severe hypersensitivity reaction (HSR). We retrospectively evaluated a cohort comprising all subjects satisfying the following conditions at 11 centres: (1) experienced a moderate-to-severe HSR to LOCM by December 2014, and (2) underwent contrast-enhanced computed tomography after the initial HSR between January 2014 and December 2014. A total of 150 patients with 328 instances of re-exposure were included; the recurrence rate of HSR was 19.5%. Patients with severe initial HSR exhibited a higher recurrence rate of severe HSR compared to patients with moderate initial HSR, despite more intensive premedication. In the multivariate analysis, the independent risk factors for recurrence of HSR were diabetes, chronic urticaria, drug allergy other than to iodinated contrast media (ICM) and severe initial HSR. The risk of recurrent HSR was 67.1% lower in cases where the implicated ICM was changed to another one (odds ratio: 0.329; P = 0.001). However, steroid premedication did not show protective effects against recurrent HSR. In high-risk patients who have previously experienced a moderate-to-severe initial HSR to LOCM, we should consider changing the implicated ICM to reduce recurrence risk. • In patients with moderate-to-severe HSR, steroid premedication only shows limited effectiveness. • Changing the implicated ICM can reduce the recurrence of HSR to ICM. • Diabetes, chronic urticaria and drug allergies increase the risk of ICM HSR.

Suggestion of the manual exposure condition guideline for reducing patient dose in digital breast tomosynthesis

Energy Technology Data Exchange (ETDEWEB)

Hong, Eun Ae [Dept. of Radiology, Korea University Guro Hospital, Seoul (Korea, Republic of); Lee, In Ja [Dept. of Radiologic Technology, Dongnam Health University, Suwon (Korea, Republic of)

2016-12-15

The conditions after exposure to digital mammography and digital breast tomosynthesis were analyzed. The examinations for the ACR phantom were done using manual exposure, not auto exposure, to examine image discrimination and patient dose. As a result, the following results were derived: In the CC exposure , the kVp was 2kVp higher while mAs decreased to 58.6% for the 3D tomography. Such result showed an approximate decrease of 60mAs. At that time, the patients Average Glandular Dose (AGD) was 1.65mGy in 2D and 1.87mGy in 3D; thus, AGD of 3D was shown to have about 1.13 times higher. The result of the manual exposure revealed a reduced mAs of up to 80%; there was no effect in the assessment standard in terms of image discrimination, resulting in more than 10 points. When mAs was reduced to 80% in the manual exposure for ACR phantom, AGD was decreased to 0.66mGy. The diagnostic values of images were maintained and patients dose was reduced in the manual exposure in the AEC condition for 3D. Since the use of 3D has recently increased, using the manual exposure has been recommended in this study to improve the diagnostic value, while, simultaneously reducing patients dose.

Medical management of severe local radiation injury after acute X-ray exposure

International Nuclear Information System (INIS)

Bushmanov, A.; Nadezhina, N.; Kretov, A.

2008-01-01

Medical management during acute period in a case of severe local radiation injury after acute X-ray exposure includes 3 stages. During the fist stage patient got conservative treatment according to the common pathogenetic mechanisms of LRI (dis aggregating therapy, stimulation of regeneration, dis intoxication therapy, antibiotic therapy, pain relief therapy, Local anti-burn therapy-specific non-adhesive bandage with antiseptic and anti-burn medicaments); estimation of severity, deepness and area of injury by clinical picture and dates of instrumental methods of examining; defining necessity and volume of surgical treatment; preparing arrangements for surgical treatment. This stage ends with forming of demarcation line of a very hard severity of a Local Radiation Injure. The second stage includes necrectomy of the area of a very hard severity with microsurgical plastic by re vascularized flap and auto dermoplastic. The third stage - adaptation of re vascularized flap and total epithelization of injured area. (author)

The relationship between occupational noise and vibration exposure and headache/eyestrain, based on the fourth Korean Working Condition Survey (KWCS).

Science.gov (United States)

Kim, Jihyun; Lee, Wanhyung; Won, Jong-Uk; Yoon, Jin-Ha; Seok, Hongdeok; Kim, Yeong-Kwang; Lee, Seunghyun; Roh, Jaehoon

2017-01-01

The individual and combined effect of occupational noise and vibration exposures, on workers' health has not been thoroughly investigated. In order to find better ways to prevent and manage workers' headache, this study aimed to investigate the effects of occupational noise and vibration exposure on headache/eyestrain. We used data from the fourth Korean Working Condition Survey (2014). After applying inclusion and exclusion criteria, 25,751 workers were included. Occupational noise and vibration exposure and the prevalence of headache/eyestrain were investigated by self-reported survey. Chi-square tests were used to compare differences in baseline characteristics between the group with headache/eyestrain and the group without. Odds ratios and 95% confidence intervals were estimated using a logistic regression model adjusted for several covariates. Area under the receiver operating characteristics curve (AUROC) analysis was used to evaluate the effect of occupational noise and/or vibration exposure. Among the 25,751 study subjects, 4,903 had experienced headache/eyestrain in the preceding year. There were significant differences in age, education level, household income, occupational classification, shift work, occupational vibration exposure, and occupational noise exposure between the two groups (all pheadache/eyestrain increased proportionally with the level of exposure, increasing from 1.08 to 1.26 with increasing vibration exposure, and from 1.25 to 1.41 with increasing noise exposure. According to the AUROC analysis, the predictive power of each exposure was significant, and increased when the two exposures were considered in combination. The findings of this study show that both occupational noise and vibration exposures are associated with headache/eyestrain; noise exposure more strongly so. However, when the two exposures are considered in combination, the explanatory power for headache/eyestrain is increased. Therefore, efforts aimed at reducing and

The effect of post-conditioning exposure to morphine on the retention of a morphine-induced conditioned taste aversion.

Science.gov (United States)

Jacobs, W J; Zellner, D A; LoLordo, V M; Riley, A L

1981-06-01

In the following experiment, multiple injections of morphine sulfate following the acquisition of a morphine-induced taste aversion had no effect on the retention of the previously acquired aversion. Post-conditioning injections of morphine resulted in the development of physical dependence to morphine and led to a decrement in the ability of morphine to induce a subsequent aversion to a second novel taste. This failure of post-conditioning exposures to morphine to affect a previously acquired morphine-induced taste aversion even though tolerance to morphine had occurred was discussed in the context of Rescorla's event-memory model of conditioning.

Severe malformations of eelpout (Zoarces viviparus) fry are induced by maternal estrogenic exposure during early embryogenesis

DEFF Research Database (Denmark)

Morthorst, Jane Ebsen; Korsgaard, Bodil; Bjerregaard, Poul

2016-01-01

Pregnant eelpout were exposed via the water to known endocrine disrupting compounds (EDCs) to clarify if EDCs could be causing the increased eelpout fry malformation frequencies observed in coastal areas receiving high anthropogenic input. The presence of a teratogenic window for estrogen...... induced by EE2 (5.7 and 17.8 ng/L) but not by 4-t-OP and pyrene. A critical period for estrogen-induced fry malformations was identified and closed between 14 and 22 days post fertilization (dpf). Exposure to 17β-estradiol (E2) between 0 and 14 dpf caused severe malformations and severity increased...... the closer exposure start was to fertilization, whereas malformations were absent by exposure starting later than 14 dpf. Data on ovarian fluid volume and larval length supported the suggested teratogenic window. Larval mortality also increased when exposure started right after fertilization....

Consequences of repeated ethanol exposure during early or late adolescence on conditioned taste aversions in rats

Directory of Open Access Journals (Sweden)

Jessica Saalfield

2015-12-01

Full Text Available Alcohol use is prevalent during adolescence, yet little is known about possible long-lasting consequences. Recent evidence suggests that adolescents are less sensitive than adults to ethanol's aversive effects, an insensitivity that may be retained into adulthood after repeated adolescent ethanol exposure. This study assessed whether intermittent ethanol exposure during early or late adolescence (early-AIE or late-AIE, respectively would affect ethanol conditioned taste aversions 2 days (CTA1 and >3 weeks (CTA2 post-exposure using supersaccharin and saline as conditioning stimuli (CS, respectively. Pair-housed male Sprague-Dawley rats received 4 g/kg i.g. ethanol (25% or water every 48 h from postnatal day (P 25–45 (early AIE or P45-65 (late AIE, or were left non-manipulated (NM. During conditioning, 30 min home cage access to the CS was followed by 0, 1, 1.5, 2 or 2.5 g/kg ethanol i.p., with testing 2 days later. Attenuated CTA relative to controls was seen among early and late AIE animals at both CTA1 and CTA2, an effect particularly pronounced at CTA1 after late AIE. Thus, adolescent exposure to ethanol was found to induce an insensitivity to ethanol CTA seen soon after exposure and lasting into adulthood, and evident with ethanol exposures not only early but also later in adolescence.

IgE sensitization and sociodemographic conditions as determinant factors in asthma severity

Directory of Open Access Journals (Sweden)

Rodrigo Gaviria

2017-12-01

Full Text Available Background: In Latin America there are few data about the factors that influence the control and severity of asthma. Objective: To describe the association between IgE sensitization to intra-home allergens and housing conditions in the severity of asthma. Methods: Sensitization to aero-allergens was evaluated by skin prick test and socio-demographic data by a questionnaire in a population between 6 and 14 years of age with diagnosis of asthma. Asthma control was measured according to spirometric results and to the application of the ACT (Asthma Control Test; the severity and symptom control was evaluated according to the GINA guideline. Results: A total of 150 resident patients from the Aburra Valley (Colombia were included. The median age of participants was 11 years, 95 (63.3 % male. 92 % of the patients resided in the urban area. Mite sensitization was the most prevalent in controlled and uncontrolled patients. Sensitization to cockroach and some poverty conditions were risk factors for asthma severity. Conclusion: Poverty conditions appear to favor the development of severe asthma and in turn IgE sensitization to cockroaches. This sensitization could serve as a biomarker of severity.

Prevalence of interpersonal trauma exposure and trauma-related disorders in severe mental illness.

Science.gov (United States)

Mauritz, Maria W; Goossens, Peter J J; Draijer, Nel; van Achterberg, Theo

2013-01-01

Interpersonal trauma exposure and trauma-related disorders in people with severe mental illness (SMI) are often not recognized in clinical practice. To substantiate the prevalence of interpersonal trauma exposure and trauma-related disorders in people with SMI. We conducted a systematic review of four databases (1980-2010) and then described and analysed 33 studies in terms of primary diagnosis and instruments used to measure trauma exposure and trauma-related disorders. Population-weighted mean prevalence rates in SMI were physical abuse 47% (range 25-72%), sexual abuse 37% (range 24-49%), and posttraumatic stress disorder (PTSD) 30% (range 20-47%). Compared to men, women showed a higher prevalence of sexual abuse in schizophrenia spectrum disorder, bipolar disorder, and mixed diagnosis groups labelled as having SMI. Prevalence rates of interpersonal trauma and trauma-related disorders were significantly higher in SMI than in the general population. Emotional abuse and neglect, physical neglect, complex PTSD, and dissociative disorders have been scarcely examined in SMI.

Excretion of lead and its biological activity several years after termination of exposure

Science.gov (United States)

Přerovská, I.; Teisinger, J.

1970-01-01

Přerovská, and Teisinger, J. (1970).Brit. J. industr. Med.,27, 352-355. Excretion of lead and its biological activity several years after termination of exposure. A group of 27 persons who had been treated some years previously for chronic lead poisoning at our clinic, and who had not come into occupational contact with lead since, was examined. Half of them had had no occupational exposure to lead for 3 to 5 years and the others for 8 to 17 years. In most of these persons there is still an increased lead excretion, originating from an increased deposit in the bones. The mobilization test after calcium versenate (CaEDTA) injection was greater than 0·350 mg/24 hours. The values found for haemoglobin, punctate basophilia, coproporphyrin and ALA in urine were normal, but there was, in all cases, a decreased ALA-D activity. This finding suggests biological activity of such negligible lead flow many years after termination of exposure. PMID:5488694

Evaluation of neutron exposure conditions for the Buffalo Reactor

International Nuclear Information System (INIS)

Lippincott, E.P.; Kellogg, L.S.; McElroy, W.N.; Baldwin, C.A.

1984-04-01

The light water test reactor at the Nuclear Science and Technology Facility of the State University of New York at Buffalo is currently being used to irradiate specimens in in-core positions for NRC-sponsored metallurgical tests. It is important that the neutron exposures for these Buffalo tests be consistent with those determined for related irradiations in the BSR and ORR reactor at ORNL. Therefore, HEDL National Reactor Dosimetry Center dosimetry procedures and ORNL calculational procedures were used for an evaluation of typical test conditions

Estrogen exposure, obesity and thyroid disease in women with severe pulmonary hypertension

Directory of Open Access Journals (Sweden)

Sweeney Lori

2009-09-01

Full Text Available Abstract Severe pulmonary hypertension is a lethal group of disorders which preferentially afflicts women. It appears that in recent years the patient profile has shifted towards older, obese, and postmenopausal women, suggesting that endocrine factors may be important. Several studies have revealed an increased prevalence of thyroid disease in these patients, but no studies have evaluated for a coexistence of endocrine factors. In particular, no studies have attempted to evaluate for concurrent thyroid disease, obesity and long-term estrogen exposure in patients. 88 patients attending the Pulmonary Hypertension Association 8th International meeting completed a questionnaire and were interviewed. Information was collected regarding reproductive history, height, weight, and previous diagnosis of thyroid disease. 46% met criteria for obesity. 41% reported a diagnosis of thyroid disease. 81% of women reported prior use of hormone therapy. 70% reported greater than 10 years of exogenous hormone use. 74% of female patients reported two or more of potentially disease modifying endocrine factors (obesity, thyroid disease or estrogen therapy. The coexistent high prevalence in our cohort of exogenous estrogen exposure, thyroid disease and obesity suggests that an interaction of multiple endocrine factors might contribute to the pathogenesis of pulmonary hypertension and may represent epigenetic modifiers in genetically-susceptible individuals.

Risk of affective disorders following prenatal exposure to severe life events: a Danish population-based cohort study.

LENUS (Irish Health Repository)

Khashan, Ali S

2012-01-31

OBJECTIVE: To examine the effect of prenatal exposure to severe life events on risk of affective disorders in the offspring. METHODS: In a cohort of 1.1 million Danish births from May 1978 until December 1997, mothers were considered exposed if one (or more) of their close relatives died or was diagnosed with serious illness up to 6 months before conception or during pregnancy. Offspring were followed up from their 10th birthday until their death, migration, onset of affective disorder or 31 December 2007; hospital admissions were identified by linkage to the Central Psychiatric Register. Log-linear Poisson regression was used for data analysis. RESULTS: The risk of affective disorders was increased in male offspring whose mothers were exposed to severe life events during the second trimester (adjusted RR 1.55 [95% CI 1.05-2.28]). There was an increased risk of male offspring affective disorders in relation to maternal exposure to death of a relative in the second trimester (adjusted RR 1.74 [95% CI 1.06-2.84]) or serious illness in a relative before pregnancy (adjusted RR 1.44 [95% CI 1.02-2.05]). There was no evidence for an association between prenatal exposure to severe life events and risk of female offspring affective disorders. CONCLUSIONS: Our population-based study suggests that prenatal maternal exposure to severe life events may increase the risk of affective disorders in male offspring. These findings are consistent with studies of populations exposed to famine and earthquake disasters which indicate that prenatal environment may influence the neurodevelopment of the unborn child.

Consequences of repeated ethanol exposure during early or late adolescence on conditioned taste aversions in rats.

Science.gov (United States)

Saalfield, Jessica; Spear, Linda

2015-12-01

Alcohol use is prevalent during adolescence, yet little is known about possible long-lasting consequences. Recent evidence suggests that adolescents are less sensitive than adults to ethanol's aversive effects, an insensitivity that may be retained into adulthood after repeated adolescent ethanol exposure. This study assessed whether intermittent ethanol exposure during early or late adolescence (early-AIE or late-AIE, respectively) would affect ethanol conditioned taste aversions 2 days (CTA1) and >3 weeks (CTA2) post-exposure using supersaccharin and saline as conditioning stimuli (CS), respectively. Pair-housed male Sprague-Dawley rats received 4g/kg i.g. ethanol (25%) or water every 48 h from postnatal day (P) 25-45 (early AIE) or P45-65 (late AIE), or were left non-manipulated (NM). During conditioning, 30 min home cage access to the CS was followed by 0, 1, 1.5, 2 or 2.5g/kg ethanol i.p., with testing 2 days later. Attenuated CTA relative to controls was seen among early and late AIE animals at both CTA1 and CTA2, an effect particularly pronounced at CTA1 after late AIE. Thus, adolescent exposure to ethanol was found to induce an insensitivity to ethanol CTA seen soon after exposure and lasting into adulthood, and evident with ethanol exposures not only early but also later in adolescence. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Solid oxide fuel cell performance under severe operating conditions

DEFF Research Database (Denmark)

Koch, Søren; Hendriksen, P.V.; Mogensen, Mogens Bjerg

2006-01-01

The performance and degradation of Solid Oxide Fuel Cells (SOFC) were studied under severe operating conditions. The cells studied were manufactured in a small series by ECN, in the framework of the EU funded CORE-SOFC project. The cells were of the anode-supported type with a double layer LSM...... cathode. They were operated at 750 °C or 850 °C in hydrogen with 5% or 50% water at current densities ranging from 0.25 A cm–2 to 1 A cm–2 for periods of 300 hours or more. The area specific cell resistance, corrected for fuel utilisation, ranged between 0.20 Ω cm2 and 0.34 Ω cm2 at 850 °C and 520 m......V, and between 0.51 Ω cm2 and 0.92 Ω cm2 at 750 °C and 520 mV. The degradation of cell performance was found to be low (ranging from 0 to 8%/1,000 hours) at regular operating conditions. Voltage degradation rates of 20 to 40%/1,000 hours were observed under severe operating conditions, depending on the test...

Preparations for Severe Winter Conditions by Emergency Health Personnel in Turkey.

Science.gov (United States)

Calışkan, Cüneyt; Algan, Aysun; Koçak, Hüseyin; Biçer, Burcu Küçük; Sengelen, Meltem; Cakir, Banu

2014-04-23

Emergency and core ambulance personnel work under all environmental conditions, including severe weather condtions. We evaluated emergency medical personnel in Çanakkale, Turkey, for their degree of preparedness. A descriptive study was conducted in Çanakkale, Turkey, within 112 emergency service units and their 17 district stations. Surveys were developed to measure the level of preparedness for serious winter conditions that individual workers made for themselves, their homes, and their cars. Of the 167 survey participants, the mean age was 29.8 ± 7.9 years; 52.7% were women; more than half (54.75%) were emergency medical technicians; and 53.3% were married. Only 10.4% of those who heated their homes with natural gas had carbon monoxide detectors. Scores relating to household and individual preparation for severe winter conditions increased by participants' age (P tires (P winter conditions (P = .016). Many of the surveyed emergency health personel demonstrated insufficient preparations for serious winter conditions. To increase the safety and efficiency of emergency medical personnel, educational training programs should be rountinely conducted. (Disaster Med Public Health Preparedness. 2014;0:1-4).

Rates of preterm birth following antenatal exposure to severe life events: A population-based cohort study

DEFF Research Database (Denmark)

Khashan, Ali; McNamee, R.; Abel, Kathryn

2009-01-01

BACKGROUND: Preterm birth and other pregnancy complications have been linked to maternal stress during pregnancy. We investigated the association between maternal exposure to severe life events and risk of preterm birth. METHODS: Mothers of all singleton live births (n = 1.35 million births...... to estimate the effect of exposure on preterm birth, very preterm birth and extremely preterm birth. RESULTS: There were 58 626 (4.34%) preterm births (births and 3288 (0.24%) extremely preterm births in the study cohort. Severe life events in close relatives in the 6...... months before conception increased the risk of preterm birth by 16% (relative risk, RR = 1.16, [95% CI: 1.08-1.23]). Severe life events in older children in the 6 months before conception increased the risk of preterm birth by 23% (RR = 1.23, [95% CI: 1.02-1.49]) and the risk of very preterm birth by 59...

Severe deterministic effects of external exposure and intake of radioactive material: basis for emergency response criteria

International Nuclear Information System (INIS)

Kutkov, V; Buglova, E; McKenna, T

2011-01-01

Lessons learned from responses to past events have shown that more guidance is needed for the response to radiation emergencies (in this context, a 'radiation emergency' means the same as a 'nuclear or radiological emergency') which could lead to severe deterministic effects. The International Atomic Energy Agency (IAEA) requirements for preparedness and response for a radiation emergency, inter alia, require that arrangements shall be made to prevent, to a practicable extent, severe deterministic effects and to provide the appropriate specialised treatment for these effects. These requirements apply to all exposure pathways, both internal and external, and all reasonable scenarios, to include those resulting from malicious acts (e.g. dirty bombs). This paper briefly describes the approach used to develop the basis for emergency response criteria for protective actions to prevent severe deterministic effects in the case of external exposure and intake of radioactive material.

Hemograms for and nutritional condition of migrant bald eagles tested for exposure to lead.

Science.gov (United States)

Miller, M J; Wayland, M E; Bortolotti, G R

2001-07-01

Plasma proteins, hematocrit, differential blood counts were examined and nutritional condition was estimated for bald eagles (Haliaeetus leucocephalus) trapped (n = 66) during antumn migration, 1994-95 at Galloway Bay (Saskatchewan, Canada), for the purposes of estimating prevalence of exposure to lead. Sex and age differences in hematocrit and plasma proteins were not observed; however, female eagles exhibited larger median absolute heterophil counts than males. Hematologic values were similar to those previously reported from eagles in captivity. Departures from expected hematological values from a healthy population of eagles were not observed in birds with elevated levels of blood lead (> or =0.200 microg/ml). Similarly, nutritional condition was not related to blood-lead concentrations. Therefore, it appears that lead exposure in this population was below a threshold required to indicate toxicological alteration in the hematological values and index of nutritional condition that we measured.

Most likely failure location during severe accident conditions

International Nuclear Information System (INIS)

Rempe, J.L.; Allison, C.M.

1991-01-01

This paper describes preliminary results from which finite element calculation results are used in conjunction with analytical calculation results to predict failure in different LWR vessel designs during a severe accident. Detailed analyses are being performed to investigate the relative likelihood of a BWR vessel and drain line penetration to fail during a wide range of severe accident conditions. Analytically developed failure maps, which were developed in terms of dimensionless groups, are applied to consider geometries and materials occurring in other LWR vessel designs. Preliminary numerical analysis results indicate that if ceramic debris relocates within the BWR drain line to a distance below the lower head, the drain line will reach failure temperatures before the vessel fails. Application of failure maps for these debris conditions to other LWR geometries indicate that in-vessel tube melting will occur in either BWR or PWR vessel designs. Furthermore, if this melt is assumed to fill the entire penetration flow area, the melt is predicted to travel well below the lower head in any of the reference LWR penetrations. However, failure maps suggest the result that ex-vessel tube temperatures exceed the penetration's ultimate strength is specific to the BWR drain line because of its material composition and relatively large effective diameter for melt flow

FAULT TREE ANALYSIS FOR EXPOSURE TO REFRIGERANTS USED FOR AUTOMOTIVE AIR CONDITIONING IN THE U.S.

Science.gov (United States)

A fault tree analysis was used to estimate the number of refrigerant exposures of automotive service technicians and vehicle occupants in the United States. Exposures of service technicians can occur when service equipment or automotive air-conditioning systems leak during servic...

The relationship between occupational noise and vibration exposure and headache/eyestrain, based on the fourth Korean Working Condition Survey (KWCS.

Directory of Open Access Journals (Sweden)

Jihyun Kim

Full Text Available The individual and combined effect of occupational noise and vibration exposures, on workers' health has not been thoroughly investigated. In order to find better ways to prevent and manage workers' headache, this study aimed to investigate the effects of occupational noise and vibration exposure on headache/eyestrain.We used data from the fourth Korean Working Condition Survey (2014. After applying inclusion and exclusion criteria, 25,751 workers were included. Occupational noise and vibration exposure and the prevalence of headache/eyestrain were investigated by self-reported survey. Chi-square tests were used to compare differences in baseline characteristics between the group with headache/eyestrain and the group without. Odds ratios and 95% confidence intervals were estimated using a logistic regression model adjusted for several covariates. Area under the receiver operating characteristics curve (AUROC analysis was used to evaluate the effect of occupational noise and/or vibration exposure.Among the 25,751 study subjects, 4,903 had experienced headache/eyestrain in the preceding year. There were significant differences in age, education level, household income, occupational classification, shift work, occupational vibration exposure, and occupational noise exposure between the two groups (all p<0.05. The odds ratios between each exposure and headache/eyestrain increased proportionally with the level of exposure, increasing from 1.08 to 1.26 with increasing vibration exposure, and from 1.25 to 1.41 with increasing noise exposure. According to the AUROC analysis, the predictive power of each exposure was significant, and increased when the two exposures were considered in combination.The findings of this study show that both occupational noise and vibration exposures are associated with headache/eyestrain; noise exposure more strongly so. However, when the two exposures are considered in combination, the explanatory power for headache

Prevalence of interpersonal trauma exposure and trauma-related disorders in severe mental illness

Directory of Open Access Journals (Sweden)

Maria W. Mauritz

2013-04-01

Full Text Available Background: Interpersonal trauma exposure and trauma-related disorders in people with severe mental illness (SMI are often not recognized in clinical practice. Objective: To substantiate the prevalence of interpersonal trauma exposure and trauma-related disorders in people with SMI. Methods: We conducted a systematic review of four databases (1980–2010 and then described and analysed 33 studies in terms of primary diagnosis and instruments used to measure trauma exposure and trauma-related disorders. Results: Population-weighted mean prevalence rates in SMI were physical abuse 47% (range 25–72%, sexual abuse 37% (range 24–49%, and posttraumatic stress disorder (PTSD 30% (range 20–47%. Compared to men, women showed a higher prevalence of sexual abuse in schizophrenia spectrum disorder, bipolar disorder, and mixed diagnosis groups labelled as having SMI. Conclusions: Prevalence rates of interpersonal trauma and trauma-related disorders were significantly higher in SMI than in the general population. Emotional abuse and neglect, physical neglect, complex PTSD, and dissociative disorders have been scarcely examined in SMI.

Lack of the correlation between biochemical effects on rats and blood carboxyhemoglobin concentrations in various conditions of single acute exposure to carbon monoxide

Energy Technology Data Exchange (ETDEWEB)

Sokal, J.A.

1975-01-01

The relationship between conditions of exposure to carbon monoxide (CO) and biochemical effects was investigated in experiments on rats. The magnitude and the time of biochemical disturbances in the tissues resulting from two different exposures consisting of 1 vol. percent CO for 4 min and 0.4 vol. percent CO for 40 min respectively were compared. In both cases, at the end of exposure the same level of blood carboxyhemoglobin (COHb) (about 50 percent) was reached. The biochemical determinations in the blood (pH, glucose, lactate, pyruvate) and brain tissue (lactate, pyruvate) were carried out immediately after termination of the exposure and after the time periods of restitution. CO exposure resulted in a decreased blood pH, increased level of blood glucose, as well as that of lactate and pyruvate both in blood and brain tissue. These changes were much more pronounced following the longer-lesser exposure than after the shorter-intense one, although blood concentrations of COHb was the same. The observed phenomenon puts some light on the frequently encountered lack of the correlation between COHb level in blood and severity of CO intoxication in clinical practice.

Acute exposure to selenium disrupts associative conditioning and long-term memory recall in honey bees (Apis mellifera).

Science.gov (United States)

Burden, Christina M; Elmore, Christopher; Hladun, Kristen R; Trumble, John T; Smith, Brian H

2016-05-01

A plethora of toxic compounds - including pesticides, heavy metals, and metalloids - have been detected in honey bees (Apis mellifera) and their colonies. One such compound is selenium, which bees are exposed to by consuming nectar and pollen from flowers grown in contaminated areas. Though selenium is lethal at high concentrations, sublethal exposure may also impair honey bees' ability to function normally. Examining the effect of selenium exposure on learning and memory provides a sensitive assay with which to identify sublethal effects on honey bee health and behavior. To determine whether sublethal selenium exposure causes learning and memory deficits, we used proboscis extension reflex conditioning coupled with recall tests 30min and 24h post-conditioning. We exposed forager honey bees to a single sublethal dose of selenium, and 3h later we used an olfactory conditioning assay to train the bees to discriminate between one odor associated with sucrose-reinforcement and a second unreinforced odor. Following conditioning we tested short- and long-term recall of the task. Acute exposure to as little as 1.8ng of an inorganic form of selenium (sodium selenate) before conditioning caused a reduction in behavioral performance during conditioning. And, exposure to 18ng of either an inorganic form (sodium selenate) or an organic form (methylseleno-l-cysteine) of selenium caused a reduction in the bees' performance during the long-term recall test. These concentrations of selenium are lower than those found in the nectar of plants grown in selenium-contaminated soil, indicating that even low-grade selenium toxicity produces significant learning and memory impairments. This may reduce foragers' ability to effectively gather resources for the colony or nurse bees' ability to care for and maintain a healthy colony. Copyright © 2016. Published by Elsevier Inc.

Cardiovascular conditions, hearing difficulty, and occupational noise exposure within US industries and occupations.

Science.gov (United States)

Kerns, Ellen; Masterson, Elizabeth A; Themann, Christa L; Calvert, Geoffrey M

2018-03-14

The purpose of this study was to estimate the prevalence of occupational noise exposure, hearing difficulty and cardiovascular conditions within US industries and occupations, and to examine any associations of these outcomes with occupational noise exposure. National Health Interview Survey data from 2014 were examined. Weighted prevalence and adjusted prevalence ratios of self-reported hearing difficulty, hypertension, elevated cholesterol, and coronary heart disease or stroke were estimated by level of occupational noise exposure, industry, and occupation. Twenty-five percent of current workers had a history of occupational noise exposure (14% exposed in the last year), 12% had hearing difficulty, 24% had hypertension, 28% had elevated cholesterol; 58%, 14%, and 9% of these cases can be attributed to occupational noise exposure, respectively. Hypertension, elevated cholesterol, and hearing difficulty are more prevalent among noise-exposed workers. Reducing workplace noise levels is critical. Workplace-based health and wellness programs should also be considered. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

Burn Pit Emissions Exposure and Respiratory and Cardiovascular Conditions Among Airborne Hazards and Open Burn Pit Registry Participants.

Science.gov (United States)

Liu, Jason; Lezama, Nicholas; Gasper, Joseph; Kawata, Jennifer; Morley, Sybil; Helmer, Drew; Ciminera, Paul

2016-07-01

The aim of this study was to determine how burn pit emissions exposure is associated with the incidence of respiratory and cardiovascular conditions. We examined the associations between assumed geographic and self-reported burn pit emissions exposure and respiratory and cardiovascular outcomes in participants of the Airborne Hazards and Open Burn Pit Registry. We found significant dose-response associations for higher risk of self-reported emphysema, chronic bronchitis, or chronic obstructive pulmonary disease with increased days of deployment within 2 miles of selected burn pits (P-trend = 0.01) and self-reported burn pit smoke exposure (P-trend = 0.0005). We found associations between burn pit emissions exposure and higher incidence of post-deployment self-reported respiratory and cardiovascular conditions, but these findings should be interpreted with caution because the surrogate measurements of burn pit emissions exposure in this analysis may not reflect individual exposure levels.

Noble gas control room accident filtration system for severe accident conditions (N-CRAFT)

International Nuclear Information System (INIS)

Hill, Axel; Stiepani, Cristoph; Drechsler, Michael

2015-01-01

Severe accidents might cause the release of airborne radioactive substances to the environment of the NPP either due to containment leakages or due to intentional filtered containment venting. In the latter case aerosols and iodine are retained, however noble gases are not retainable by the FCVS or by conventional air filtration systems like HEPA filters and iodine absorbers. Radioactive noble gases nevertheless dominate the activity release depending on the venting procedure and the weather conditions. To prevent unacceptable contamination of the control room atmosphere by noble gases, AREVA GmbH has developed a noble gas control room accident filtration system (CRAFT) which can supply purified fresh air to the control room without time limitation. The retention process is based on dynamic adsorption of noble gases on activated carbon. The system consists of delay lines (carbon columns) which are operated by a continuous and simultaneous adsorption and desorption process. CRAFT allows minimization of the dose rate inside the control room and ensures low radiation exposure to the staff by maintaining the control room environment suitable for prolonged occupancy throughout the duration of the accident. CRAFT consists of a proven modular design either transportable or permanently installed. (author)

Key Parameters for Operator Diagnosis of BWR Plant Condition during a Severe Accident

Energy Technology Data Exchange (ETDEWEB)

Clayton, Dwight A [ORNL; Poore III, Willis P [ORNL

2015-01-01

The objective of this research is to examine the key information needed from nuclear power plant instrumentation to guide severe accident management and mitigation for boiling water reactor (BWR) designs (specifically, a BWR/4-Mark I), estimate environmental conditions that the instrumentation will experience during a severe accident, and identify potential gaps in existing instrumentation that may require further research and development. This report notes the key parameters that instrumentation needs to measure to help operators respond to severe accidents. A follow-up report will assess severe accident environmental conditions as estimated by severe accident simulation model analysis for a specific US BWR/4-Mark I plant for those instrumentation systems considered most important for accident management purposes.

Air exposure behavior of the semiterrestrial crab Neohelice granulata allows tolerance to severe hypoxia but not prevent oxidative damage due to hypoxia-reoxygenation cycle.

Science.gov (United States)

de Lima, Tábata Martins; Geihs, Márcio Alberto; Nery, Luiz Eduardo Maia; Maciel, Fábio Everton

2015-11-01

The air exposure behavior of the semi-terrestrial crab Neohelice granulata during severe hypoxia was studied. This study also verified whether this behavior mitigates possible oxidative damage, namely lipoperoxidation, caused by hypoxia and reoxygenation cycles. The lethal time for 50% of the crabs subjected to severe hypoxia (0.5 mgO2 · L(-1)) with free access to air was compared to that of crabs subjected to severe hypoxia without access to air. Crabs were placed in aquaria divided into three zones: water (when the animal was fully submersed), land (when the animal was completely emerged) and intermediate (when the animal was in contact with both environments) zones. Then the crabs were held in this condition for 270 min, and the time spent in each zone was recorded. Lipid peroxidation (LPO) damage to the walking leg muscles was determined for the following four experimental conditions: a--normoxic water with free access to air; b--hypoxic water without access to air; c--hypoxic water followed by normoxic water without air access; and d--hypoxic water with free access to air. When exposed to hypoxic water, N. granulata spent significantly more time on land, 135.3 ± 17.7 min, whereas control animals (exposed to normoxic water) spent more time submerged, 187.4 ± 20.2 min. By this behavior, N. granulata was able to maintain a 100% survival rate when exposed to severe hypoxia. However, N. granulata must still return to water after periods of air exposure (~ 14 min), causing a sequence of hypoxia/reoxygenation events. Despite increasing the survival rate, hypoxia with air access does not decrease the lipid peroxidation damage caused by the hypoxia and reoxygenation cycle experienced by these crabs.

Urinary bisphenol A concentrations and their implications for human exposure in several Asian countries.

Science.gov (United States)

Zhang, Zifeng; Alomirah, Husam; Cho, Hyeon-Seo; Li, Yi-Fan; Liao, Chunyang; Minh, Tu Binh; Mohd, Mustafa Ali; Nakata, Haruhiko; Ren, Nanqi; Kannan, Kurunthachalam

2011-08-15

Bisphenol A (BPA) is an industrial chemical used in the manufacture of polycarbonate plastics and epoxy resins. Due to the potential of this compound to disrupt normal endocrinal functions, concerns over human exposure to BPA have been raised. Although several studies have reported human exposure to BPA in Western nations, little is known about exposure in Asian countries. In this study, we determined total urinary BPA concentrations (free plus conjugated) in 296 urine samples (male/female: 153/143) collected from the general population in seven Asian countries, China, India, Japan, Korea, Kuwait, Malaysia, and Vietnam, using high-performance liquid chromatography (HPLC) tandem mass spectrometry (MS/MS). On the basis of urinary BPA concentrations, we estimated the total daily intake. The results indicated that BPA was detected in 94.3% of the samples analyzed, at concentrations ranging from Malaysia (1.06 ng/mL, 2.31 μg/g), and Japan (0.95 ng/mL, 0.58 μg/g). Among the five age groups studied (≤ 19, 20-29, 30-39, 40-49, and ≥ 50 years), the highest median concentration of BPA was found in urine samples from the age group of ≤ 19 years. There was no significant difference in BPA concentrations between genders (male and female) or domicile of residence (rural and urban). The estimated median daily intakes of BPA for the populations in Kuwait, Korea, India, China, Vietnam, Malaysia, and Japan were 5.19, 3.69, 2.90, 2.13, 2.01, 1.80, and 1.61 μg/day, respectively. The estimated daily intake of BPA in the seven Asian countries was significantly lower than the tolerable daily intake recommended by the U.S. Environmental Protection Agency. This is the first study to document the occurrence of and human exposure to BPA in several Asian countries.

Risk of early or severe pre-eclampsia related to pre-existing conditions

DEFF Research Database (Denmark)

Catov, Janet M; Ness, Roberta B; Kip, Kevin E

2007-01-01

BACKGROUND: Preeclampsia (PE), especially severe or early PE, is a leading cause of morbidity and mortality among mothers and infants. We estimated the population attributable fractions of severe or early PE associated with pre-existing conditions among nulliparous and multiparous women. METHODS...

Adolescent delta-9-tetrahydrocannabinol (THC) exposure fails to affect THC-induced place and taste conditioning in adult male rats.

Science.gov (United States)

Wakeford, Alison G P; Flax, Shaun M; Pomfrey, Rebecca L; Riley, Anthony L

2016-01-01

Adolescent initiation of drug use has been linked to problematic drug taking later in life and may represent an important variable that changes the balance of the rewarding and/or aversive effects of abused drugs which may contribute to abuse vulnerability. The current study examined the effects of adolescent THC exposure on THC-induced place preference (rewarding effects) and taste avoidance (aversive effects) conditioning in adulthood. Forty-six male Sprague-Dawley adolescent rats received eight injections of an intermediate dose of THC (3.2mg/kg) or vehicle. After these injections, animals were allowed to mature and then trained in a combined CTA/CPP procedure in adulthood (PND ~90). Animals were given four trials of conditioning with intervening water-recovery days, a final CPP test and then a one-bottle taste avoidance test. THC induced dose-dependent taste avoidance but did not produce place conditioning. None of these effects was impacted by adolescent THC exposure. Adolescent exposure to THC had no effect on THC taste and place conditioning in adulthood. The failure to see an effect of adolescent exposure was addressed in the context of other research that has assessed exposure of drugs of abuse during adolescence on drug reactivity in adulthood. Copyright © 2015 Elsevier Inc. All rights reserved.

Use of lead aprons - further considerations of estimation of doses and conditions of acute exposures of TLD badge in diagnostic x-ray institutions

International Nuclear Information System (INIS)

Pradhan, A.S.; Chatterjee, S.

2003-01-01

In the recent study the authors reported that the exposure conditions of the use of the TLD badge, whether worn under or over the lead apron could be estimated from the readout of the TLD badge used in X-ray diagnostic departments. The effectiveness of lead aprons procured from different suppliers having the same value of quoted nominal lead equivalence was found to vary severely and this indicated some limitation in the applicability of the method of evaluation of exposure conditions of the badge. The transmission factors for the lead aprons varied up to a factor of 15 for the same value of quoted nominal lead equivalence procured from three different suppliers. This is of serious consequences in radiation protection and attracts attention for quality control. An error in the estimation of the exposure conditions of the TLD badge could lead to an underestimation of doses up to 4 times using the prevalent method. The estimation of the actual doses of radiation workers in the cases of over-exposures for the situations of the use of the TLD badge over the lead apron showed that the variation in the quality of lead aprons could be wrong in the range from 1.6 to 25 times even if the kVp of the machine is exactly known. Therefore, attempt should not be made to estimate the actual doses under lead apron from the readout of the TLD badge worn over the apron, as the real values of the transmission factors of the aprons and kVp of the X-ray machine may not be available. (author)

Relationship between exposure duration, carboxyhemoglobin, blood glucose, pyruvate and lactate and the severity of intoxication in 39 cases of acute carbon monoxide poisoning in man

Energy Technology Data Exchange (ETDEWEB)

Sokal, J.A.; Kralkowska, E.

1985-08-01

The relationship between exposure duration, COHb, blood glucose, pyruvate and lactate and the severity of intoxication was investigated in a group of 39 cases of acute CO poisoning treated in the Clinical Toxicology Center in Lodz, Poland. On the basis of clinical criteria the patients were classified into cases of mild, moderate, severe and very severe CO poisoning. COHb and carbohydrate metabolites were estimated in venous blood taken immediately after admission of the patient to hospital prior to treatment. The severity of intoxication did not correlate with blood COHb; variation in exposure duration seems to be responsible for this phenomenon. Severe and very severe poisonings were associated with longer exposures and were accompanied by a markedly higher blood lactate level, compared to mild and moderate cases. Blood pyruvate depended less than lactate on the severity of intoxication. Blood glucose depended neither on exposure duration nor on the severity of intoxication. Among the carbohydrate metabolic parameters studied, blood lactate determination can be helpful in the evaluation of the severity of CO poisoning in man.

Identification of severe wind conditions using a Reynolds averaged Navier-Stokes solver

DEFF Research Database (Denmark)

Sørensen, Niels N.; Bechmann, Andreas; Johansen, Jeppe

2007-01-01

The present paper describes the application of a Navier-Stokes solver to predict the presence of severe flow conditions in complex terrain, capturing conditions that may be critical to the siting of wind turbines in the terrain. First it is documented that the flow solver is capable of predicting...

Effects of prior amphetamine exposure on approach strategy in appetitive Pavlovian conditioning in rats.

Science.gov (United States)

Simon, Nicholas W; Mendez, Ian A; Setlow, Barry

2009-03-01

Pavlovian conditioning with a discrete reward-predictive visual cue can elicit two classes of behaviors: "sign-tracking" (approach toward and contact with the cue) and "goal-tracking" (approach toward the site of reward delivery). Sign-tracking has been proposed to be linked to behavioral disorders involving compulsive reward-seeking, such as addiction. Prior exposure to psychostimulant drugs of abuse can facilitate reward-seeking behaviors through enhancements in incentive salience attribution. Thus, it was predicted that a sensitizing regimen of amphetamine exposure would increase sign-tracking behavior. The purpose of these experiments was to determine how a regimen of exposure to amphetamine affects subsequent sign-tracking behavior. Male Long-Evans rats were given daily injections of d-amphetamine (2.0 mg/kg) or saline for 5 days, then given a 7-day drug-free period followed by testing in a Pavlovian conditioning task. In experiment 1, rats were presented with a visual cue (simultaneous illumination of a light and extension of a lever) located either to the left or right of a centrally located food trough. One cue (CS+) was always followed by food delivery, whereas the other (CS-) was not. In experiment 2, rats were tested in a nondiscriminative (CS+ only) version of the task. In both experiments, amphetamine-exposed rats showed less sign-tracking and more goal-tracking compared to saline controls. Contrary to predictions, prior amphetamine exposure decreased sign-tracking and increased goal-tracking behavior. However, these results do support the hypothesis that psychostimulant exposure and incentive sensitization enhance behavior directed toward reward-proximal cues at the expense of reward-distal cues.

Determination of gamma-ray exposure rate from short-lived fission products under criticality accident conditions

International Nuclear Information System (INIS)

Yanagisawa, Hiroshi; Ohno, Akio; Aizawa, Eijyu

2002-01-01

For the assessment of γ-ray doses from short-lived fission products (FPs) under criticality accident conditions, γ-ray exposure rates varying with time were experimentally determined in the Transient Experiment Critical Facility (TRACY). The data were obtained by reactivity insertion in the range of 1.50 to 2.93$. It was clarified from the experiments that the contribution of γ-ray from short-lived FPs to total exposure during the experiments was evaluated to be 15 to 17%. Hence, the contribution cannot be neglected for the assessment of γ-ray doses under criticality accident conditions. Computational analyses also indicated that γ-ray exposure rates from short-lived FPs calculated with the Monte Carlo code, MCNP4B, and photon sources based on the latest FP decay data, the JENDL FP Decay Data File 2000, well agreed with the experimental results. The exposure rates were, however, extremely underestimated when the photon sources were obtained by the ORIGEN2 code. The underestimation is due to lack of energy-dependent photon emission data for major short-lived FP nuclides in the photon database attached to the ORIGEN2 code. It was also confirmed that the underestimation arose in 1,000 or less of time lapse after an initial power burst. (author)

An analysis of gender differences in patients with hand eczema - everyday exposures, severity, and consequences

DEFF Research Database (Denmark)

Mollerup, Annette; Veien, Niels Kren; Johansen, Jeanne Duus

2014-01-01

, aggravating factors, hand eczema-related consequences and quality of life were obtained from a questionnaire. RESULTS: Men and women had equal clinical severities of disease, with an overall median HECSI of 43. Self-reported medication adherence was equal between the genders, but, among patients aged > 40...... years, more reported higher adherence. The impact of disease was larger in women than in men. Women reported significantly more aggravating factors and sick leave. Also, women had a more impaired quality of life than men at equal levels of disease severity, and this could be associated with the higher......BACKGROUND: Hand eczema is often related to high-risk occupations and aggravating exposures in everyday life. The disease is twice as frequent in women as in men, partly because of diverse exposure patterns. Other gender differences may be relevant for treatment and prevention. OBJECTIVES: To gain...

Using the Aerasense NanoTracer for simultaneously obtaining several ultrafine particle exposure metrics

International Nuclear Information System (INIS)

Marra, J

2011-01-01

The expanding production and use of nanomaterials increases the chance of human exposure to engineered nanoparticles (NP), also referred to as ultrafine particles (UFP; ≤ 100 - 300 nm). This is particularly true in workplaces where they can become airborne and thereafter inhaled by workers during nanopowder processing. Considering the suspected hazard of many engineered UFPs, the general recommendation is to take measures for minimizing personal exposure while monitoring the UFP pollution for assessment and control purposes. The portable Aerasense NanoTracer accomplishes this UFP monitoring, either intermittently or in real time. This paper reviews its design and operational characteristics and elaborates on a number of application extensions and constraints. The NanoTracer's output signals enable several UFP exposure metrics to be simultaneously inferred. These include the airborne UFP number concentration and the number-averaged particle size, serving as characteristics of the pertaining UFP pollution. When non-hygroscopic particles are involved, the NanoTracer's output signals also allow an estimation of the lung-deposited UFP surface area concentration and the lung-deposited UFP mass concentration. It is thereby possible to distinguish between UFP depositions in the alveolar region, the trachea-bronchial region and the head airway region, respectively, by making use of the ICRP particle deposition model.

Suitable exposure conditions for CB Throne? New model cone beam computed tomography unit for dental use

International Nuclear Information System (INIS)

Tanabe, Kouji; Nishikawa, Keiichi; Yajima, Aya; Mizuta, Shigeru; Sano, Tsukasa; Yajima, Yasutomo; Nakagawa, Kanichi; Kousuge, Yuuji

2008-01-01

The CB Throne is a cone beam computed tomography unit for dental use, and the smaller version of the CB MercuRay developed by Hitachi Medico Co. We investigated which exposure conditions were suitable in the clinical use. Suitable exposure conditions were determined by simple subjective comparisons. The right temporomandibular joint of the head phantom was scanned at all possible combinations of tube voltage (60, 80, 100, 120 kV) and tube current (10, 15 mA). Oblique-sagittal images of the same position were obtained using multiplanar reconstruction (MPR) function. Images obtained at 120 kV and 15 mA, which are the highest exposure conditions and certain to produce images of the best quality, were used to establish the standard. Eight oral radiologists observed each image and standard image on a LCD monitor. They compared subjectively spatial resolution and noise between each image and standard image using a 10 cm scale. Evaluation points were obtained from the check positions on the scales. The Steel method was used to determine significant differences. The images at 60 kV/10 mA and 80 kV/15 mA showed significantly lower evaluation points on spatial resolution. The images at 60 kV/10 mA, 60 kV/15 mA and 80 kV/10 mA showed significantly lower evaluation points on noise. In conclusion, even if exposure conditions are reduced to 100 kV/10 mA, 100 kV/15 mA or 120 kV/10 mA, the CB Throne will produce images of the best quality. (author)

Association between Air Pollution Exposure, Cognitive and Adaptive Function, and ASD Severity among Children with Autism Spectrum Disorder

Science.gov (United States)

Kerin, Tara; Volk, Heather; Li, Weiyan; Lurmann, Fred; Eckel, Sandrah; McConnell, Rob; Hertz-Picciotto, Irva

2018-01-01

Prenatal exposure to air pollution has been associated with autism spectrum disorder (ASD) risk but no study has examined associations with ASD severity or functioning. Cognitive ability, adaptive functioning, and ASD severity were assessed in 327 children with ASD from the Childhood Autism Risks from Genetics and the Environment study using the…

Simple preconditioning technique: empirical formula for condition number reduction at a junction of several wires

CSIR Research Space (South Africa)

Lysko, AA

2011-08-01

Full Text Available The condition number for a method-of-moments’ impedance matrix resulting from a junction of several wires is frequency dependant and can be minimized at a given frequency using several approaches. An empirical formula for an optimum, condition...

The effects of intermittent exposure to low pH and oxygen conditions on survival and growth of juvenile red abalone

Science.gov (United States)

Kim, T. W.; Barry, J. P.; Micheli, F.

2013-02-01

Exposure of nearshore animals to hypoxic, low pH waters upwelled from below the continental shelf and advected near the coast may be stressful to marine organisms and lead to impaired physiological performance. We mimicked upwelling conditions in the laboratory and tested the effect of fluctuating exposure to water with low pH and/or low oxygen levels on the mortality and growth of juvenile red abalone (Haliotis rufescens, shell length 5-10 mm). Mortality rates of juvenile abalone exposed to low pH (7.5, total scale) and low O2 (40% saturation, 5 mg L-1) conditions for periods of 3 to 6 h every 3-5 days over 2 weeks did not differ from those exposed to control conditions (O2: 100% saturation, 12 mg L-1; pH 8.0). However, when exposure was extended to 24 h repeated twice over a 15 day period, juveniles experienced higher mortality in the low oxygen treatments compared to control conditions, regardless of pH levels (pH 7.5 vs. 8.0). Growth rates were reduced significantly when juveniles were exposed to low pH or low oxygen treatments and the growth was lowest when low pH exposure was combined with low O2. Furthermore, individual variation of growth rate increased when they were exposed to low pH and low O2 conditions. These results indicate that prolonged exposure to low oxygen levels is detrimental for the survival of red abalone, whereas both pH and oxygen is a crucial factor for their growth. However, given the higher individual variation in growth rate, they may have an ability to adapt to extended exposure to upwelling conditions.

Reducing condition number by appropriate current decomposition on a multiplet of several wires

CSIR Research Space (South Africa)

Lysko, AA

2011-07-01

Full Text Available This paper discusses a numerical investigation in connection with the dependency of the condition number of the impedance matrix on the decomposition of current on a junction with several attached wires (multiplet). It is shown that the condition...

An evaluation of several methods for assessing the effects of occupational exposure to radiation

International Nuclear Information System (INIS)

Gilbert, E.S.

1983-01-01

Several methods for the analysis of occupational radiation exposure data, including procedures based on Cox's proportional hazards model, are presented and evaluated. Issues of interest include the contribution of an external control, the effective handling of highly skewed exposure data, and the potential for detecting effects in populations occupationally exposed to radiation. Expressions for evaluating the power of various procedures are derived and applied to data from the Hanford population in order to determine power curves for detecting leukemia effects, with both additive and multiplicative linear models being used. It is found that the introduction of an external control can increase power, although not when an overall adjustment factor must be estimated from the data or when death rates for the study population are substantially lower than those for the control population. It is also found that very little power is lost if exposures are grouped. Finally, the power calculations indicate, as expected, that in analyses of occupationally exposed populations, such as the Hanford workers, there is very little chance of detecting radiation effects at the levels of our current estimates. However, power is reasonably good for detecting effects that are 10 to 15 times larger

Estimation of Exposure Doses for Several Scenarios of the Landfill Disposal of NORM Wastes

Energy Technology Data Exchange (ETDEWEB)

Jeong, Jong Tae; Ko, Nak Yul; Baik, Min Hoon [KAERI, Daejeon (Korea, Republic of); Yoon, Ki Hoon [Korea Institude of Nuclear Safety, Daejeon (Korea, Republic of)

2016-05-15

The Act on safety control of radioactive materials around living environment was promulgated to protect citizen's health and environment in 2013. According to this Act, the integrated plan for radiation protection and the necessary safety guides for treatment, reuse, and disposal of NORM wastes have to be made. And NORM wastes have to be disposed in landfill sites by reducing the concentration of radionuclide, and they should not be reutilized. In this study, we estimated exposure doses for several scenarios for NORM (Naturally Occurring Radioactive Materials) waste disposal into a reference landfill site to check the radiological safety. Also, we estimated the amount of NORM wastes for different activity levels of important radionuclides in wastes to be disposed into a landfill site based on the exposure dose limits to support the establishment of technical bases for safety guide. We estimated the amount of NORM wastes for different activity levels of wastes containing U series, Th series, and {sup 40}K based on the exposure dose limits. The results of this study can be used as technical bases to support the establishment of a guide for the safe management of NORM waste disposal.

Thermal stress analysis of reactor containment building considering severe weather condition

International Nuclear Information System (INIS)

Lee, Yun; Kim, Yun-Yong; Hyun, Jung-Hwan; Kim, Do-Gyeum

2014-01-01

Highlights: • We examine that through-wall crack risk in cold weather is high. • It is predicted that cracking in concrete wall will not happen in hot region. • Cracking due to hydration heat can be controlled by appropriate curing condition. • Temperature differences between inner and outer face is relatively small in hot weather. - Abstract: Prediction of concrete cracking due to hydration heat in mass concrete such as reactor containment building (RCB) in nuclear power plant is a crucial issue in construction site. In this study, the numerical analysis for heat transfer and stress development is performed for the containment wall in RCB by considering the severe weather conditions. Finally, concrete cracking risk in hot and cold weather is discussed based on analysis results. In analyses considering severe weather conditions, it is found that the through-wall cracking risk in cold weather is high due to the abrupt temperature difference between inside concrete and the ambient air in cold region. In hot weather, temperature differences between inner and outer face is relatively small, and accordingly the relevant cracking risk is relatively low in contrast with cold weather

Study of the effectiveness of a participatory ergonomics intervention in reducing worker pain severity through physical exposure pathways.

Science.gov (United States)

Laing, Andrew C; Frazer, Mardon B; Cole, Donald C; Kerr, Mickey S; Wells, Richard P; Norman, Robert W

2005-02-01

A participatory ergonomics programme was implemented in an automotive parts manufacturing factory. An ergonomics change team was formed composed of members from management and the organized labour union. It was hypothesized that the physical change projects implemented as part of this process would result in decreased worker exposures to peak and cumulative physical demands and reduced worker perceptions of physical effort and pain severity. A quasi-experimental design was employed, utilizing a sister plant in the corporation as a referent group. A longitudinal questionnaire approach was used to document pre-post changes in worker perceptions. In general, the physical change projects were rated as improvements by workers and were successful at reducing peak and/or cumulative mechanical exposures. However, there were few systematic changes in perceived effort or pain severity levels. Explanations include the confounding effects of differential production rate and staffing changes at the intervention and referent plants and/or insufficient overall intervention intensity due to a relatively short intervention period, plant and team ambivalence towards the process and the low overall impact on exposure of the particular changes implemented.

Weather conditions conducive to Beijing severe haze more frequent under climate change

Science.gov (United States)

Cai, Wenju; Li, Ke; Liao, Hong; Wang, Huijun; Wu, Lixin

2017-03-01

The frequency of Beijing winter severe haze episodes has increased substantially over the past decades, and is commonly attributed to increased pollutant emissions from China’s rapid economic development. During such episodes, levels of fine particulate matter are harmful to human health and the environment, and cause massive disruption to economic activities, as occurred in January 2013. Conducive weather conditions are an important ingredient of severe haze episodes, and include reduced surface winter northerlies, weakened northwesterlies in the midtroposphere, and enhanced thermal stability of the lower atmosphere. How such weather conditions may respond to climate change is not clear. Here we project a 50% increase in the frequency and an 80% increase in the persistence of conducive weather conditions similar to those in January 2013, in response to climate change. The frequency and persistence between the historical (1950-1999) and future (2050-2099) climate were compared in 15 models under Representative Concentration Pathway 8.5 (RCP8.5). The increased frequency is consistent with large-scale circulation changes, including an Arctic Oscillation upward trend, weakening East Asian winter monsoon, and faster warming in the lower troposphere. Thus, circulation changes induced by global greenhouse gas emissions can contribute to the increased Beijing severe haze frequency.

Extracorporeal Membrane Oxygenation (ECMO) for Severe Toxicological Exposures: Review of the Toxicology Investigators Consortium (ToxIC).

Science.gov (United States)

Wang, G S; Levitan, R; Wiegand, T J; Lowry, J; Schult, R F; Yin, S

2016-03-01

Although there have been many developments related to specific strategies for treating patients after poisoning exposures, the mainstay of therapy remains symptomatic and supportive care. One of the most aggressive supportive modalities is extracorporeal membrane oxygenation (ECMO). Our goal was to describe the use of ECMO for toxicological exposures reported to the American College of Medical Toxicology (ACMT) Toxicology Investigators Consortium (ToxIC). We performed a retrospective review of the ACMT ToxIC Registry from January 1, 2010 to December 31, 2013. Inclusion criteria included patients aged 0 to 89 years, evaluated between January 2010 through December 2013, and received ECMO for toxicological exposure. There were 26,271 exposures (60 % female) reported to the ToxIC Registry, 10 (0.0004 %) received ECMO: 4 pediatric (18 years). Time of initiation of ECMO ranged from 4 h to 4 days, with duration from 15 h to 12 days. Exposures included carbon monoxide/smoke inhalation (2), bitter almonds, methanol, and several medications including antihistamines (2), antipsychotic/antidepressant (2), cardiovascular drugs (2), analgesics (2), sedative/hypnotics (2), and antidiabetics (2). Four ECMO patients received cardiopulmonary resuscitation (CPR) during their hospital course, and the overall survival rate was 80 %. ECMO was rarely used for poisoning exposures in the ACMT ToxIC Registry. ECMO was utilized for a variety of ages and for pharmaceutical and non-pharmaceutical exposures. In most cases, ECMO was administered prior to cardiovascular failure, and survival rate was high. If available, ECMO may be a valid treatment modality.

Beyond Extinction: Prolonged Conditioning and Repeated Threat Exposure Abolish Contextual Renewal of Fear-Potentiated Startle Discrimination but Leave Expectancy Ratings Intact.

Science.gov (United States)

Leer, Arne; Haesen, Kim; Vervliet, Bram

2018-01-01

Extinction treatments decrease fear via repeated exposures to the conditioned stimulus (CS) and are associated with a return of fear. Alternatively, fear can be reduced via reductions in the perceived intensity of the unconditioned stimulus (US), e.g., through repeated exposures to the US. Promisingly, the few available studies show that repeated US exposures outperform standard extinction. US exposure treatments can decrease fear via two routes: (1) by weakening the CS-US association (extinction-like mechanism), and/or (2) by weakening the subjective US aversiveness (habituation-like mechanism). The current study further investigated the conditions under which US exposure treatment may reduce renewal, by adding a group in which CS-US pairings continued following fear acquisition. During acquisition, participants learned that one of two visual stimuli (CS+/CS-) predicted the occurrence of an aversive electrocutaneous stimulus (US). Next, the background context changed and participants received one of three interventions: repeated CS exposures, (2) repeated US exposures, or (3) continued CS-US pairings. Following repeated CS exposures, test presentations of the CSs in the original conditioning context revealed intact CS+/CS- differentiation in the fear-potentiated startle reflex, while the differentiation was abolished in the other two groups. Differential US expectancy ratings, on the other hand, were intact in all groups. Skin conductance data were inconclusive because standard context renewal following CS exposures did not occur. Unexpectedly, there was no evidence for a habituation-like process having taken place during US exposures or continued CS-US pairings. The results provide further evidence that US exposures outperform the standard extinction treatment and show that effects are similar when US exposures are part of CS-US pairings.

Effects of microplastic exposure on the body condition and behaviour of planktivorous reef fish (Acanthochromis polyacanthus)

Science.gov (United States)

Hoogenboom, Mia O.

2018-01-01

The effect of a pollutant on the base of the food web can have knock-on effects for trophic structure and ecosystem functioning. In this study we assess the effect of microplastic exposure on juveniles of a planktivorous fish (Acanthochromis polyacanthus), a species that is widespread and abundant on Indo-Pacific coral reefs. Under five different plastic concentration treatments, with plastics the same size as the natural food particles (mean 2mm diameter), there was no significant effect of plastic exposure on fish growth, body condition or behaviour. The amount of plastics found in the gastro-intestinal (GI) tract was low, with a range of one to eight particles remaining in the gut of individual fish at the end of a 6-week plastic-exposure period, suggesting that these fish are able to detect and avoid ingesting microplastics in this size range. However, in a second experiment the number of plastics in the GI tract vastly increased when plastic particle size was reduced to approximately one quarter the size of the food particles, with a maximum of 2102 small (plastic exposure period. Under conditions where food was replaced by plastic, there was a negative effect on the growth and body condition of the fish. These results suggest plastics could become more of a problem as they break up into smaller size classes, and that environmental changes that lead to a decrease in plankton concentrations combined with microplastic presence is likely have a greater influence on fish populations than microplastic presence alone. PMID:29494635

Exposure history determines pteropod vulnerability to ocean acidification along the US West Coast.

Science.gov (United States)

Bednaršek, N; Feely, R A; Tolimieri, N; Hermann, A J; Siedlecki, S A; Waldbusser, G G; McElhany, P; Alin, S R; Klinger, T; Moore-Maley, B; Pörtner, H O

2017-07-03

The pteropod Limacina helicina frequently experiences seasonal exposure to corrosive conditions (Ω ar   US West Coast and is recognized as one of the species most susceptible to ocean acidification (OA). Yet, little is known about their capacity to acclimatize to such conditions. We collected pteropods in the California Current Ecosystem (CCE) that differed in the severity of exposure to Ω ar conditions in the natural environment. Combining field observations, high-CO 2 perturbation experiment results, and retrospective ocean transport simulations, we investigated biological responses based on histories of magnitude and duration of exposure to Ω ar  history of exposure to corrosive conditions. Pteropods from the coastal CCE appear to be at or near the limit of their physiological capacity, and consequently, are already at extinction risk under projected acceleration of OA over the next 30 years. Our results demonstrate that Ω ar exposure history largely determines pteropod response to experimental conditions and is essential to the interpretation of biological observations and experimental results.

Severe sunburn and subsequent risk of primary cutaneous malignant melanoma in scotland.

Science.gov (United States)

MacKie, R. M.; Aitchison, T.

1982-01-01

A case-control study of occupational and recreational sun exposure, Mediterranean and other sun-exposed holidays, tanning history and history of isolated episodes of severe sunburn has been carried out on 113 patients with cutaneous malignant melanoma and 113 age- and sex-matched controls. Social class and skin type were also considered in the analysis of the data which involved the use of conditional multiple logistic regression. A highly significant increase in the history of severe sunburn was recorded in melanoma patients of both sexes in the 5-year period preceding presentation with their tumour. Higher social class and negative history of recreational sun exposure were also significantly increased in patients by comparison with controls. In the male group severe sunburn, lack of occupational sun exposure and higher social class were significant factors while in the female group only severe sunburn was significantly increased in the melanoma patients. This study thus provides evidence to suggest that short intense episodes of UV exposure resulting in burning may be one of the aetiological factors involved in subsequent development of melanoma. PMID:7150488

The Association Between Pitch Conditions and the Incidence of ...

African Journals Online (AJOL)

shown to influence incidence of rugby injuries. Harsh weather conditions and detrimental effect on poor Kenyan rugby pitches create a unique environment for injury exposure. We conducted a whole population prospective cohort study to determine the association of pitch conditions with injury incidence and severity.

Noble gas control room accident filtration system for severe accident conditions N-CRAFT. System design

International Nuclear Information System (INIS)

Hill, Axel

2014-01-01

Severe accidents might cause the release of airborne radioactive substances to the environment of the NPP. This can either be due to leakages of the containment or due to a filtered containment venting in order to ensure the overall integrity of the containment. During the containment venting process aerosols and iodine can be retained by the FCVS which prevents long term ground contamination. Noble gases are not retainable by the FCVS. From this it follows that a large amount of radioactive noble gases (e.g. xenon, krypton) might be present in the nearby environment of the plant dominating the activity release, depending on the venting procedure and the weather conditions. Accident management measures are necessary in case of severe accidents and the prolonged stay of staff inside the main control room (MCR) or emergency response center (ERC) is essential. Therefore, the in leakage and contamination of the MRC and ERC with airborne activity has to be prevented. The radiation exposure of the crises team needs to be minimized. The entrance of noble gases cannot be sufficiently prevented by the conventional air filtration systems such as HEPA filters and iodine absorbers. With the objective to prevent an unacceptable contamination of the MCR/ERC atmosphere by noble gases AREVA GmbH has developed a noble gas retention system. The noble gas control room accident filtration system CRAFT is designed for this case and provides supply of fresh air to the MCR/ERC without time limitation. The retention process of the system is based on the dynamic adsorption of noble gases on activated carbon. The system consists of delay lines (carbon columns) which are operated by a continuous and simultaneous adsorption and desorption process. These cycles ensure a periodic load and flushing of the delay lines retaining the noble gases from entering the MCR. CRAFT allows a minimization of the dose rate inside MCR/ERC and ensures a low radiation exposure to the staff on shift maintaining

Radiographic detection of initial carious lesions on the proximal surfaces of teeth. Part I. The influence of exposure conditions

International Nuclear Information System (INIS)

Arnold, L.V.

1987-01-01

The relationship between a number of technical exposure conditions and the diagnostic value of bitewing radiographs in the interpretation of initial proximal carious lesions was evaluated. The most important exposure factors for radiographs are tube voltage, filtration, and exposure time. Tube voltage and filtration were found to have an insignificant influence on the diagnostic quality. Exposure time proved to be the most critical factor in influencing diagnostic quality. The greatest difference in diagnostic quality, however, was caused by differences between observers

Determining the effect of worker exposure conditions on the risk of hearing loss in noisy industrial workroom using Cox proportional hazard model.

Science.gov (United States)

Aliabadi, Mohsen; Fereidan, Mohammad; Farhadian, Maryam; Tajik, Leila

2015-01-01

In noisy workrooms, exposure conditions such as noise level, exposure duration and use of hearing protection devices are contributory factors to hearing loss. The aim of this study was to determine the effect of exposure conditions on the risk of hearing loss using the Cox model. Seventy workers, employed in a press workshop, were selected to study their hearing threshold using an audiometric test. Their noise exposure histories also were analyzed. The results of the Cox model showed that the job type, smoking and the use of protection devices were effective to induce hearing loss. The relative risk of hearing loss in smokers was 1.1 times of non-smokers The relative risk of hearing loss in workers with the intermittent use of protection devices was 3.3 times those who used these devices continuously. The Cox model could analyze the effect of exposure conditions on hearing loss and provides useful information for managers in order to improve hearing conservation programs.

Effects of microplastic exposure on the body condition and behaviour of planktivorous reef fish (Acanthochromis polyacanthus).

Science.gov (United States)

Critchell, Kay; Hoogenboom, Mia O

2018-01-01

The effect of a pollutant on the base of the food web can have knock-on effects for trophic structure and ecosystem functioning. In this study we assess the effect of microplastic exposure on juveniles of a planktivorous fish (Acanthochromis polyacanthus), a species that is widespread and abundant on Indo-Pacific coral reefs. Under five different plastic concentration treatments, with plastics the same size as the natural food particles (mean 2mm diameter), there was no significant effect of plastic exposure on fish growth, body condition or behaviour. The amount of plastics found in the gastro-intestinal (GI) tract was low, with a range of one to eight particles remaining in the gut of individual fish at the end of a 6-week plastic-exposure period, suggesting that these fish are able to detect and avoid ingesting microplastics in this size range. However, in a second experiment the number of plastics in the GI tract vastly increased when plastic particle size was reduced to approximately one quarter the size of the food particles, with a maximum of 2102 small (< 300μm diameter) particles present in the gut of individual fish after a 1-week plastic exposure period. Under conditions where food was replaced by plastic, there was a negative effect on the growth and body condition of the fish. These results suggest plastics could become more of a problem as they break up into smaller size classes, and that environmental changes that lead to a decrease in plankton concentrations combined with microplastic presence is likely have a greater influence on fish populations than microplastic presence alone.

Exposure to acute severe hypoxia leads to increased urea loss and disruptions in acid-base and ionoregulatory balance in dogfish sharks (Squalus acanthias).

Science.gov (United States)

Zimmer, Alex M; Wood, Chris M

2014-01-01

The effects of acute moderate (20% air O2 saturation; 6-h exposure) and severe (5% air O2 saturation; 4-h exposure) hypoxia on N-waste, acid-base, and ion balance in dogfish sharks (Squalus acanthias suckleyi) were evaluated. We predicted that the synthesis and/or retention of urea, which are active processes, would be inhibited by hypoxia. Exposure to moderate hypoxia had negligible effects on N-waste fluxes or systemic physiology, except for a modest rise in plasma lactate. Exposure to severe hypoxia led to a significant increase in urea excretion (Jurea), while plasma, liver, and muscle urea concentrations were unchanged, suggesting a loss of urea retention. Ammonia excretion (Jamm) was elevated during normoxic recovery. Moreover, severe hypoxia led to disruptions in acid-base balance, indicated by a large increase in plasma [lactate] and substantial decreases in arterial pHa and plasma [Formula: see text], as well as loss of ionic homeostasis, indicated by increases in plasma [Mg(2+)], [Ca(2+)], and [Na(+)]. We suggest that severe hypoxia in dogfish sharks leads to a reduction in active gill homeostatic processes, such as urea retention, acid-base regulation and ionoregulation, and/or an osmoregulatory compromise due to increased functional gill surface area. Overall, the results provide a comprehensive picture of the physiological responses to a severe degree of hypoxia in an ancient fish species.

Breakthrough or one-hit wonder? Three attempts to replicate single-exposure musical conditioning effects on choice behavior (Gorn, 1982).

NARCIS (Netherlands)

Vermeulen, I.E.; Batenburg, A.E.; Beukeboom, C.J.; Smits, T.

2014-01-01

Three studies replicated a classroom experiment on single-exposure musical conditioning of consumer choice (Gorn, 1982), testing whether simultaneous exposure to liked (vs. disliked) music and a pen image induced preferences for the shown (vs. a different) pen. Experiments 1 and 2 employed the

Association of pediatric asthma severity with exposure to common household dust allergens

International Nuclear Information System (INIS)

Gent, Janneane F.; Belanger, Kathleen; Triche, Elizabeth W.; Bracken, Michael B.; Beckett, William S.; Leaderer, Brian P.

2009-01-01

Background: Reducing exposure to household dust inhalant allergens has been proposed as one strategy to reduce asthma. Objective: To examine the dose-response relationships and health impact of five common household dust allergens on disease severity, quantified using both symptom frequency and medication use, in atopic and non-atopic asthmatic children. Methods: Asthmatic children (N=300) aged 4-12 years were followed for 1 year. Household dust samples from two indoor locations were analyzed for allergens including dust mite (Der p 1, Der f 1), cat (Fel d 1), dog (Can f 1), cockroach (Bla g 1). Daily symptoms and medication use were collected in monthly telephone interviews. Annual disease severity was examined in models including allergens, specific IgE sensitivity and adjusted for age, gender, atopy, ethnicity, and mother's education. Results: Der p 1 house dust mite allergen concentration of 2.0 μg/g or more from the main room and the child's bed was related to increased asthma severity independent of allergic status (respectively, OR 2.93, 95% CI 1.37, 6.30 for 2.0-10.0 μg/g and OR 2.55 95% CI 1.13, 5.73 for ≥10.0 μg/g). Higher pet allergen levels were associated with greater asthma severity, but only for those sensitized (cat OR 2.41 95% CI 1.19, 4.89; dog OR 2.06 95% CI 1.01, 4.22). Conclusion: Higher levels of Der p 1 and pet allergens were associated with asthma severity, but Der p 1 remained an independent risk factor after accounting for pet allergens and regardless of Der p 1 specific IgE status.

Association of pediatric asthma severity with exposure to common household dust allergens

Energy Technology Data Exchange (ETDEWEB)

Gent, Janneane F., E-mail: janneane.gent@yale.edu [Yale Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, One Church Street, 6th Floor, New Haven, CT 06510 (United States); Belanger, Kathleen [Yale Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, One Church Street, 6th Floor, New Haven, CT 06510 (United States); Triche, Elizabeth W. [Brown University, Department of Community Health/Epidemiology, Providence, RI (United States); Bracken, Michael B. [Yale Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, One Church Street, 6th Floor, New Haven, CT 06510 (United States); Beckett, William S. [Mount Auburn Hospital, Department of Internal Medicine, Cambridge, MA (United States); Leaderer, Brian P. [Yale Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, One Church Street, 6th Floor, New Haven, CT 06510 (United States)

2009-08-15

Background: Reducing exposure to household dust inhalant allergens has been proposed as one strategy to reduce asthma. Objective: To examine the dose-response relationships and health impact of five common household dust allergens on disease severity, quantified using both symptom frequency and medication use, in atopic and non-atopic asthmatic children. Methods: Asthmatic children (N=300) aged 4-12 years were followed for 1 year. Household dust samples from two indoor locations were analyzed for allergens including dust mite (Der p 1, Der f 1), cat (Fel d 1), dog (Can f 1), cockroach (Bla g 1). Daily symptoms and medication use were collected in monthly telephone interviews. Annual disease severity was examined in models including allergens, specific IgE sensitivity and adjusted for age, gender, atopy, ethnicity, and mother's education. Results: Der p 1 house dust mite allergen concentration of 2.0 {mu}g/g or more from the main room and the child's bed was related to increased asthma severity independent of allergic status (respectively, OR 2.93, 95% CI 1.37, 6.30 for 2.0-10.0 {mu}g/g and OR 2.55 95% CI 1.13, 5.73 for {>=}10.0 {mu}g/g). Higher pet allergen levels were associated with greater asthma severity, but only for those sensitized (cat OR 2.41 95% CI 1.19, 4.89; dog OR 2.06 95% CI 1.01, 4.22). Conclusion: Higher levels of Der p 1 and pet allergens were associated with asthma severity, but Der p 1 remained an independent risk factor after accounting for pet allergens and regardless of Der p 1 specific IgE status.

Operating features of decorative polymer-impregnated concretes under severe operating conditions

International Nuclear Information System (INIS)

Kapustina, I.B.; Lobasenok, V.A.; Yakimtsiv, V.P.

1991-01-01

The study was carried out to investigate the possibility of a decorative polymer-impregnated concrete as a lining material in radiation-endangered rooms. Their extreme properties such as radiation resistance, decontamination ability, fire resistance and melting-freezing cycle resistance were studied. The material proposed shows substantially high resistance under severe operating conditions

Effects of heavy metal exposure on the condition and health of nestlings of the great tit (Parus major), a small songbird species

Energy Technology Data Exchange (ETDEWEB)

Janssens, Ellen; Dauwe, Tom; Pinxten, Rianne; Bervoets, Lieven; Blust, Ronny; Eens, Marcel

2003-11-01

Pollutants reduced nestling body mass and condition and delayed fledging time. - In this study we examined the possible effects of heavy metal exposure on the condition and health of great tit nestlings (Parus major) at four study sites along a pollution gradient near a large non-ferrous smelter in Belgium during three consecutive breeding seasons. Our results showed that nestlings were indeed exposed to large amounts of heavy metals. Excrements contained significantly higher concentrations of several heavy metals (silver, arsenic, cadmium, mercury, lead) near the pollution source than at study sites farther away. When taking into account the number of young in the nest at the time of sampling, nestling body mass and condition were significantly reduced at the most polluted site. Nestlings at the two most polluted sites fledged significantly later than at the least polluted site. We also observed growth abnormalities of the legs near the pollution source. Tarsus length, wing length and haematocrit values did not differ significantly among study sites.

Effects of heavy metal exposure on the condition and health of nestlings of the great tit (Parus major), a small songbird species

International Nuclear Information System (INIS)

Janssens, Ellen; Dauwe, Tom; Pinxten, Rianne; Bervoets, Lieven; Blust, Ronny; Eens, Marcel

2003-01-01

Pollutants reduced nestling body mass and condition and delayed fledging time. - In this study we examined the possible effects of heavy metal exposure on the condition and health of great tit nestlings (Parus major) at four study sites along a pollution gradient near a large non-ferrous smelter in Belgium during three consecutive breeding seasons. Our results showed that nestlings were indeed exposed to large amounts of heavy metals. Excrements contained significantly higher concentrations of several heavy metals (silver, arsenic, cadmium, mercury, lead) near the pollution source than at study sites farther away. When taking into account the number of young in the nest at the time of sampling, nestling body mass and condition were significantly reduced at the most polluted site. Nestlings at the two most polluted sites fledged significantly later than at the least polluted site. We also observed growth abnormalities of the legs near the pollution source. Tarsus length, wing length and haematocrit values did not differ significantly among study sites

A single exposure to severe stressors causes long-term desensitisation of the physiological response to the homotypic stressor.

Science.gov (United States)

Armario, Antonio; Vallès, Astrid; Dal-Zotto, Silvina; Márquez, Cristina; Belda, Xavier

2004-09-01

Although some laboratories have reported that a single session of stress is able to induce a long-lasting sensitisation of the hypothalamic-pituitary-adrenal (HPA) response to further exposures to stress, we have found that a single exposure to severe emotional (immobilisation, restraint or shock) or systemic (endotoxin) stressors reduces the responsiveness of the HPA to the same, but not to a novel (heterotypic), stressor, in which case a slight sensitisation was observed. Long-term desensitisation has been found to reduce not only secretion of peripheral HPA hormones (ACTH and corticosterone), but also to reduce responses of central components of the HPA axis (c-fos and CRF gene expression at the level of the paraventricular nucleus of the hypothalamus, PVN). In addition, desensitisation also applies to the impact of the stressor on food intake and, probably, to stress-induced hyperglycaemia. The development of long-term desensitisation of the HPA axis does not appear to be a universal consequence of exposure to severe stressors as it was not observed in response to insulin-induced hypoglycaemia. Whether or not the development of long-term effects of stress depend on the specific pathways activated by particular stressors remains to be tested. The observed desensitisation of the HPA axis in response to the homotypic stressor shows two special features which makes it difficult to be interpreted in terms of an habituation-like process: (a) the effect increased with time (days to weeks) elapsed between the first and second exposure to the stressor, suggesting a progressive maturational process; and (b) the stronger the stressor the greater the long-term desensitisation. Therefore, it is possible that desensitisation of the HPA axis is the sum of two different phenomena: long-term effects and habituation-like processes. The contribution of the former may be more relevant with severe stressors and longer inter-stress intervals, and that of the latter with mild

Analysis of the injury severity of crashes by considering different lighting conditions on two-lane rural roads.

Science.gov (United States)

Jafari Anarkooli, A; Hadji Hosseinlou, M

2016-02-01

Many studies have examined different factors contributing to the injury severity of crashes; however, relatively few studies have focused on the crashes by considering the specific effects of lighting conditions. This research investigates lighting condition differences in the injury severity of crashes using 3-year (2009-2011) crash data of two-lane rural roads of the state of Washington. Separate ordered-probit models were developed to predict the effects of a set of factors expected to influence injury severity in three lighting conditions; daylight, dark, and dark with street lights. A series of likelihood ratio tests were conducted to determine if these lighting condition models were justified. The modeling results suggest that injury severity in specific lighting conditions are associated with contributing factors in different ways, and that such differences cannot be uncovered by focusing merely on one aggregate model. Key differences include crash location, speed limit, shoulder width, driver action, and three collision types (head-on, rear-end, and right-side impact collisions). This paper highlights the importance of deploying street lights at and near intersections (or access points) on two-lane rural roads because injury severity highly increases when crashes occur at these points in dark conditions. Copyright © 2016 Elsevier Ltd and National Safety Council. All rights reserved.

Deformation and stress in PMMA during hard X-ray exposure for deep lithography

International Nuclear Information System (INIS)

Moldovan, N.

1999-01-01

The availability of high-energy, high-flux, collimated synchrotrons radiation has extended the application of deep X-ray lithography (DXRL) to thickness values of the PMMA resist of several millimeters. Some of the most severe limitations come from plastic deformation, stress, and cracks induced in PMMA during exposure and development. We have observed and characterized these phenomena quantitatively. Profilometry measurements revealed that the PMMA is subjected either to local shrinkage or to expansion, while compression and expansion evolve over time. Due to material loss and crosslinking, the material undergoes a shrinkage, while the radiation-induced decomposition generates gases expanding the polymer matrix. The overall dynamics of the material microrelief and stress during and after the exposure depend on the balance between compaction and outgassing. These depend in turn on the exposure conditions (spectrum; dose, dose rate, seaming, temperature), post-exposure storage conditions, PMMA material properties and thickness, and also on the size and geometry of the exposed patterns

Thermalydraulic processes in the reactor coolant system of a BWR under severe accident conditions

International Nuclear Information System (INIS)

Hodge, S.A.

1990-01-01

Boiling water reactors (BWRs) incorporate many unique structural features that make their expected response under severe accident conditions very different from that predicted in the case of pressurized water reactor accident sequences. Automatic main steam isolation valve (MIV) closure as the vessel water level approaches the top of the core would cause reactor vessel isolation while automatic recirculation pump trip would limit the in-vessel flows to those characteristic of natural circulation (as disturbed by vessel relief valve actuation). This paper provides a discussion of the BWR control blade, channel box, core plate, control rod guide tube, and reactor vessel safety relief valve (SRV) configuration and the effects of these structural components upon thermal hydraulic processes within the reactor vessel under severe accident conditions. The dominant BWR severe accident sequences as determined by probabilistic risk assessment are described and the expected timing of events for the unmitigated short-term station blackout severe accident sequence at the Peach Bottom atomic power station is presented

Modulation of Radiation responses by pre-exposure to irradiated Cell conditioned medium.

LENUS (Irish Health Repository)

Maguire, Paula

2007-04-01

The aim of this study was to investigate whether exposure of HPV-G cells to irradiated cell conditioned medium (ICCM) could induce an adaptive response if the cells were subsequently challenged with a higher ICCM dose. Clonogenic survival and major steps in the cascade leading to apoptosis, such as calcium influx and loss of mitochondrial membrane potential, were examined to determine whether these events could be modified by giving a priming dose of ICCM before the challenge dose. Clonogenic survival data indicated an ICCM-induced adaptive response in HPV-G cells "primed" with 5 mGy or 0.5 Gy ICCM for 24 h and then exposed to 0.5 Gy or 5 Gy ICCM. Reactive oxygen species (ROS) were found to be involved in the bystander-induced cell death. Calcium fluxes varied in magnitude across the exposed cell population, and a significant number of the primed HPV-G cells did not respond to the challenge ICCM dose. No significant loss of mitochondrial membrane potential was observed when HPV-G cells were exposed to 0.5 Gy ICCM for 24 h followed by exposure to 5 Gy ICCM for 6 h. Exposure of HPV-G cells to 5 mGy ICCM for 24 h followed by exposure to 0.5 Gy ICCM for 18 h caused a significant increase in mitochondrial mass and a change in mitochondrial location, events associated with the perpetuation of genomic instability. This study has shown that a priming dose of ICCM has the ability to induce an adaptive response in HPV-G cells subsequently exposed to a challenge dose of ICCM.

Determination of Radiological, Material and Organizational Measures for Reuse of Conditionally Released Materials from Decommissioning

International Nuclear Information System (INIS)

Ondra, F.; Vasko, M.; Necas, V.

2012-01-01

An important part of nuclear installation decommissioning is conditional release of materials. The mass of conditionally released materials can significantly influence radioactive waste management and capacity of radioactive waste repository. The influence on a total decommissioning cost is also not negligible. Several scenarios for reuse of conditionally released materials were developed within CONRELMAT project. Each scenario contains preparation phase, construction phase and operation phase. For each above mentioned phase is needed to determine radiological, material, organizational and other constraints for conditionally released materials reuse to not break exposure limits for staff and public. Constraints are determined on the basis of external and internal exposure calculations in created models for selected takes in particular scenarios phases. The paper presents a developed methodology for determination of part of above mentioned constraints concerning external exposure of staff or public. Values of staff external exposure are also presented in paper to ensure that staff or public exposure does not break the limits. The methodology comprises a proposal of following constraints: radionuclide limit concentration of conditionally released materials for specific scenarios and nuclide vectors, specific deployment of conditionally released materials eventually shielding materials, staff and public during the scenario's phases, organizational measures concerning time of staff's or public's stay in the vicinity of conditionally released materials for individual performed scenarios and nuclide vectors. The paper further describes VISIPLAN 3D ALARA calculation planning software tool used for calculation of staff's and public's external exposure for individual scenarios. Several other parallel papers proposed for HND2012 are presenting selected details of the project.(author).

Severe Pulmonary Toxicity After Myeloablative Conditioning Using Total Body Irradiation: An Assessment of Risk Factors

International Nuclear Information System (INIS)

Kelsey, Chris R.; Horwitz, Mitchell E.; Chino, Junzo P.; Craciunescu, Oana; Steffey, Beverly; Folz, Rodney J.; Chao, Nelson J.; Rizzieri, David A.; Marks, Lawrence B.

2011-01-01

Purpose: To assess factors associated with severe pulmonary toxicity after myeloablative conditioning using total body irradiation (TBI) followed by allogeneic stem cell transplantation. Methods and Materials: A total of 101 adult patients who underwent TBI-based myeloablative conditioning for hematologic malignancies at Duke University between 1998 and 2008 were reviewed. TBI was combined with high-dose cyclophosphamide, melphalan, fludarabine, or etoposide, depending on the underlying disease. Acute pulmonary toxicity, occurring within 90 days of transplantation, was scored using Common Terminology Criteria for Adverse Events version 3.0. Actuarial overall survival and the cumulative incidence of acute pulmonary toxicity were calculated via the Kaplan-Meier method and compared using a log-rank test. A binary logistic regression analysis was performed to assess factors independently associated with acute severe pulmonary toxicity. Results: The 90-day actuarial risk of developing severe (Grade 3-5) pulmonary toxicity was 33%. Actuarial survival at 90 days was 49% in patients with severe pulmonary toxicity vs. 94% in patients without (p < 0.001). On multivariate analysis, the number of prior chemotherapy regimens was the only factor independently associated with development of severe pulmonary toxicity (odds ratio, 2.7 per regimen). Conclusions: Severe acute pulmonary toxicity is prevalent after TBI-based myeloablative conditioning regimens, occurring in approximately 33% of patients. The number of prior chemotherapy regimens appears to be an important risk factor.

Radiation-induced taste aversion: effects of radiation exposure level and the exposure-taste interval

International Nuclear Information System (INIS)

Spector, A.C.; Smith, J.C.; Hollander, G.R.

1986-01-01

Radiation-induced taste aversion has been suggested to possibly play a role in the dietary difficulties observed in some radiotherapy patients. In rats, these aversions can still be formed even when the radiation exposure precedes the taste experience by several hours. This study was conducted to examine whether increasing the radiation exposure level could extend the range of the exposure-taste interval that would still support the formation of a taste aversion. Separate groups of rats received either a 100 or 300 R gamma-ray exposure followed 1, 3, 6, or 24 h later by a 10-min saccharin (0.1% w/v) presentation. A control group received a sham exposure followed 1 h later by a 10-min saccharin presentation. Twenty-four hours following the saccharin presentation all rats received a series of twelve 23-h two-bottle preference tests between saccharin and water. The results indicated that the duration of the exposure-taste interval plays an increasingly more important role in determining the initial extent of the aversion as the dose decreases. The course of recovery from taste aversion seems more affected by dose than by the temporal parameters of the conditioning trial

Experimental results from containment piping bellows subjected to severe accident conditions: Results from bellows tested in corroded conditions. Volume 2

International Nuclear Information System (INIS)

Lambert, L.D.; Parks, M.B.

1995-10-01

Bellows are an integral part of the containment pressure boundary in nuclear power plants. They are used at piping penetrations to allow relative movement between piping and the containment wall, while minimizing the load imposed on the piping and wall. Piping bellows are primarily used in steel containments; however, they have received limited use in some concrete (reinforced and prestressed) containments. In a severe accident they may be subjected to pressure and temperature conditions that exceed the design values, along with a combination of axial and lateral deflections. A test program to determine the leak-tight capacity of containment penetration bellows is being conducted at Sandia National Laboratories under the sponsorship of the US Nuclear Regulatory Commission. Several different bellows geometries, representative of actual containment bellows, have been subjected to extreme deflections along with pressure and temperature loads. The bellows geometries and loading conditions are described along with the testing apparatus and procedures. A total of nineteen bellows have been tested. Thirteen bellows were tested in ''like-new'' condition (results reported in Volume 1), and six were tested in a corroded condition. The tests showed that bellows in ''like-new'' condition are capable of withstanding relatively large deformations, up to, or near, the point of full compression or elongation, before developing leakage, while those in a corroded condition did not perform as well, depending on the amount of corrosion. The corroded bellows test program and results are presented in this report

Neurological condition in 42-month-old children in relation to pre- and postnatal exposure to polychlorinated biphenyls and dioxins.

NARCIS (Netherlands)

Patandin, S; Fidler, [No Value; Weisglas-Kuperus, N; Sauer, PJJ; Boersma, ER; Touwen, BCL

1998-01-01

Adverse neurological effects of exposure to PCBs have been found up to 18 months of age. Now we report on the effect of pre-and postnatal exposure to PCBs and dioxins on the neurological condition at 42 months of age. For this purpose, PCB levels were determined in cord and maternal plasma, and used

Numerical Study of Severe Accidents on Containment Venting Conditions

Energy Technology Data Exchange (ETDEWEB)

Lee, Na Rae; Bang, Young Suk; Park, Tong Kyu; Lee, Doo Yong [FNC Technology Co., Yongin (Korea, Republic of); Choi, Yu Jung; Lee, Sang Won; Kim, Hyeong Taek [KHNP-CRI, Daejeon (Korea, Republic of)

2014-10-15

Under severe accident, the containment integrity can be challenged due to over-pressurization by steam and non-condensable gas generation. According to Seismic Probabilistic Safety Assessment (PSA) result, the late containment failure by over-pressurization has been identified as the most probable containment failure mode. In addition, the analyses of Fukushima nuclear power plant accident reveal the necessity of the proper containment depressurization to prevent the large release of the radionuclide to environment. Containment venting has been considered as an effective approach to maintain the containment integrity from over-pressurization. Basic idea of containment venting is to relieve the pressure inside of the containment by establishing a flow path to the external environment. To ensure the containment integrity under over-pressure conditions, it is crucial to conduct the containment vent in a timely manner with a sufficient discharge flow rate. It is also important to optimize the vent line size to prevent additional risk of leakage and to install at the site with limited space availability. The purpose of this study is to identify the effective venting conditions for preventing the containment over-pressurization and investigate the vent flow characteristics to minimize the consequence of the containment ventilation.. In order that, thermodynamic behavior of the containment and the discharged flow depending on different vent strategies are analyzed and compared. The representative accident scenarios are identified by reviewing the Level 2 PSA result and the sensitivity analyses with varying conditions (i.e. vent line size and vent initiation pressure) are conducted. MAAP5 model for the OPR1000 Korea nuclear power plant has been used for severe accident simulations. Containment venting can be an effective strategy to prevent the significant failure of the containment due to over-pressurization. However, it should be carefully conducted because the vented

Numerical Study of Severe Accidents on Containment Venting Conditions

International Nuclear Information System (INIS)

Lee, Na Rae; Bang, Young Suk; Park, Tong Kyu; Lee, Doo Yong; Choi, Yu Jung; Lee, Sang Won; Kim, Hyeong Taek

2014-01-01

Under severe accident, the containment integrity can be challenged due to over-pressurization by steam and non-condensable gas generation. According to Seismic Probabilistic Safety Assessment (PSA) result, the late containment failure by over-pressurization has been identified as the most probable containment failure mode. In addition, the analyses of Fukushima nuclear power plant accident reveal the necessity of the proper containment depressurization to prevent the large release of the radionuclide to environment. Containment venting has been considered as an effective approach to maintain the containment integrity from over-pressurization. Basic idea of containment venting is to relieve the pressure inside of the containment by establishing a flow path to the external environment. To ensure the containment integrity under over-pressure conditions, it is crucial to conduct the containment vent in a timely manner with a sufficient discharge flow rate. It is also important to optimize the vent line size to prevent additional risk of leakage and to install at the site with limited space availability. The purpose of this study is to identify the effective venting conditions for preventing the containment over-pressurization and investigate the vent flow characteristics to minimize the consequence of the containment ventilation.. In order that, thermodynamic behavior of the containment and the discharged flow depending on different vent strategies are analyzed and compared. The representative accident scenarios are identified by reviewing the Level 2 PSA result and the sensitivity analyses with varying conditions (i.e. vent line size and vent initiation pressure) are conducted. MAAP5 model for the OPR1000 Korea nuclear power plant has been used for severe accident simulations. Containment venting can be an effective strategy to prevent the significant failure of the containment due to over-pressurization. However, it should be carefully conducted because the vented

Effect of histochrome on the severity of delayed effects of prenatal exposure to lead nitrate in the rat brain.

Science.gov (United States)

Ryzhavsky, B Ya; Lebedko, O A; Belolubskaya, D S

2008-08-01

The effects of histochrome on the severity of delayed effects of prenatal exposure to lead nitrate were studied in the rat brain. Exposure of pregnant rats to lead nitrate during activation of free radical oxidation reduced activity of NADH- and NADPH-dehydrogenases in cortical neurons of their 40-day-old progeny, reduced the number of neurons in a visual field, increased the number of pathologically modified neurons, and stimulated rat motor activity in an elevated plus-maze. Two intraperitoneal injections of histochrome in a dose of 0.1 mg/kg before and after lead citrate challenge attenuated the manifestations of oxidative stress and prevented the changes in some morphological and histochemical parameters of the brain, developing under the effect of lead exposure.

Electrical equipment performance under severe accident conditions (BWR/Mark 1 plant analysis): Summary report

International Nuclear Information System (INIS)

Bennett, P.R.; Kolaczkowski, A.M.; Medford, G.T.

1986-09-01

The purpose of the Performance Evaluation of Electrical Equipment during Severe Accident States Program is to determine the performance of electrical equipment, important to safety, under severe accident conditions. In FY85, a method was devised to identify important electrical equipment and the severe accident environments in which the equipment was likely to fail. This method was used to evaluate the equipment and severe accident environments for Browns Ferry Unit 1, a BWR/Mark I. Following this work, a test plan was written in FY86 to experimentally determine the performance of one selected component to two severe accident environments

The effects of intermittent exposure to low-pH and low-oxygen conditions on survival and growth of juvenile red abalone

Science.gov (United States)

Kim, T. W.; Barry, J. P.; Micheli, F.

2013-11-01

Exposure of nearshore animals to hypoxic, low-pH waters upwelled from below the continental shelf and advected near the coast may be stressful to marine organisms and lead to impaired physiological performance. We mimicked upwelling conditions in the laboratory and tested the effect of fluctuating exposure to water with low-pH and/or low-oxygen levels on the mortality and growth of juvenile red abalone (Haliotis rufescens, shell length 5-10 mm). Mortality rates of juvenile abalone exposed to low-pH (7.5, total scale) and low-O2 (40% saturation, mg L-1) conditions for periods of 3 to 6 h every 3-5 days over 2 weeks did not differ from those exposed to control conditions (O2: 100% saturation, 12 mg L-1; pH 8.0). However, when exposure was extended to 24 h, twice over a 15-day period, juveniles experienced 5-20% higher mortality in the low-oxygen treatments compared to control conditions. Growth rates were reduced significantly when juveniles were exposed to low-oxygen and low-pH treatments. Furthermore, individual variation of growth rate increased when juveniles were exposed simultaneously to low-pH and low-O2 conditions. These results indicate that prolonged exposure to low-oxygen levels is detrimental for the survival of red abalone, whereas pH is a crucial factor for their growth. However, the high individual variation in growth rate under low levels of both pH and oxygen suggests that cryptic phenotypic plasticity may promote resistance to prolonged upwelling conditions by a portion of the population.

Assessment of dermal exposure and skin condition of workers exposed to nickel at a South African base metal refinery.

Science.gov (United States)

Du Plessis, Johannes L; Eloff, Frederik C; Badenhorst, Casper J; Olivier, Johretha; Laubscher, Petrus J; Van Aarde, Michiel N; Franken, Anja

2010-01-01

The objectives of this study were to assess dermal exposure of cell workers to nickel at a South African base metal refinery and to characterize their skin condition by measuring the skin hydration and trans epidermal water loss (TEWL) indices. The skin hydration index of the index finger, palm, neck, and forehead was measured before, during and at the end of the shift. The TEWL index was measured before and at the end of the shift. Dermal exposure samples were collected with Ghostwipes from the index finger and palm of the dominant hand, before, during, and at the end of the shift. Neck and forehead samples were collected before and at the end of the shift. Wipe samples of various surfaces in the workplace were also collected. Wipes were analyzed for nickel according to NIOSH method 9102, using inductively coupled plasma-atomic emission spectrometry. Hydration indices measured on the hands decreased significantly during the shift, but recovered to normal levels by the end of the shift. TEWL indices for the index finger and palm of the hands are indicative of a low barrier function even before commencement of the shift, which further deteriorated significantly during the shift. During the shift, substantial nickel skin loading occurred on the index finger and palm of the hand. Levels on the neck and forehead were much lower. Various workplace surfaces, which workers come into contact with, were also contaminated with nickel. The skin condition and high levels of nickel on the skin were most probably caused by inadequate chemical protection provided by protective gloves. Although, the permeability of nickel through intact skin is considered to be low, a decreased barrier function of dehydrated or slightly damaged skin will increase its permeability for nickel. The ethnicity of these exposed workers may contribute significantly toward the low incidence of allergic contact dermatitis observed. Several measures to lower dermal exposure to nickel are also recommended.

Conditions for oxygen-deficient combustion during accidents with severe core concrete thermal attack

International Nuclear Information System (INIS)

Luangdilok, W.; Elicson, G.T.; Berger, W.E. Jr.

1993-01-01

This paper addresses the interactions between MCCI (molten core-concrete interactions)-induced offgas releases, mostly the combustible gases, natural circulation between the cavity and the lower containment based on recent research developments in the area of mixed convection flow (Epstein, et al., 1989; Epstein, 1988; Epstein, 1992) between compartments, and their effects on combustion in PWR containments during prolonged severe accidents. Specifically, large dry PWR containments undergoing severe core-concrete attack during station blackouts where the containment atmosphere is expected to be inerted are objects of this analysis. The purpose of this paper, given the conditions that oxygen can be brought to the cavity, is to demonstrate that consumption of most oxygen present in the containment can be achieved in a reasonable time scale assuming that combustion is not subject to flammability limits due to the high cavity temperatures. The conditions for cavity combustion depend on several factors including good gas flowpaths between the cavity and other containment regions, and combustion processes within the cavity with the hot debris acting as the ignition source

Condition monitoring and maintenance of nuclear power plant concrete structures

International Nuclear Information System (INIS)

Orr, R.; Prasad, N.

1988-01-01

Nuclear power plant concrete structures are potentially subject to deterioration due to several environmental conditions, including weather exposure, ground water exposure, and sustained high temperature and radiation levels. The nuclear power plant are generally licensed for a term of 40 years. In order to maximize the return from the existing plants, feasibility studies are in progress for continued operation of many of these plants beyond the original licensed life span. This paper describes a study that was performed with an objective to define appropriate condition monitoring and maintenance procedures. A timely implementation of a condition monitoring and maintenance program would provide a valuable database and would provide justification for extension of the plant's design life. The study included concrete structures such as the containment buildings, interior structures, basemats, intake structures and cooling towers. Age-related deterioration at several operating power plants was surveyed and the potential degradation mechanisms have been identified

Chemical phenomena under severe accident conditions

International Nuclear Information System (INIS)

Powers, D.A.

1988-01-01

A severe nuclear reactor accident is expected to involve a vast number of chemical processes. The chemical processes of major safety significance begin with the production of hydrogen during steam oxidation of fuel cladding. Physico-chemical changes in the fuel and the vaporization of radionuclides during reactor accidents have captured much of the attention of the safety community in recent years. Protracted chemical interactions of core debris with structural concrete mark the conclusion of dynamic events in a severe accident. An overview of the current understanding of chemical processes in severe reactor accident is provided in this paper. It is shown that most of this understanding has come from application of findings from other fields though a few areas have in the past been subject to in-depth study of a fundamental nature. Challenges in the study of severe accident chemistry are delineated

Real-time personal exposure and health condition monitoring system

Energy Technology Data Exchange (ETDEWEB)

Saitou, Isamu; Kanda, Hiroaki; Asai, Akio; Takeishi, Naoki; Ota, Yoshito [Hitachi Aloka Medical, Ltd., Measuring Systems Engineering Dept., Tokyo (Japan); Hanawa, Nobuhiro; Ueda, Hisao; Kusunoki, Tsuyoshi; Ishitsuka, Etsuo; Kawamura, Hiroshi [Japan Atomic Energy Agency, Oarai Research and Development Center, Oarai, Ibaraki (Japan)

2012-03-15

JAEA (Japan Atomic Energy Agency) and HAM (Hitachi Aloka Medical, Ltd) have proposed novel monitoring system for workers of nuclear facility. In these facilities, exposure management for workers is mainly used access control and personal exposure recordings. This system is currently only for reports management but is not confirmative for surveillance when work in progress. Therefore, JAEA and HAM integrate access control and personal exposure recordings and two real-time monitoring systems which are position sensing and vital sign monitor. Furthermore change personal exposure management to real-time management, this system integration prevents workers from risk of accidents, and makes possible take appropriate action quickly. This novel system is going to start for tentative operation, using position sensing and real-time personal dosimeter with database in Apr. 2012. (author)

Estimate of radionuclide release characteristics into containment under severe accident conditions

International Nuclear Information System (INIS)

Nourbakhsh, H.P.

1993-11-01

A detailed review of the available light water reactor source term information is presented as a technical basis for development of updated source terms into the containment under severe accident conditions. Simplified estimates of radionuclide release and transport characteristics are specified for each unique combination of the reactor coolant and containment system combinations. A quantitative uncertainty analysis in the release to the containment using NUREG-1150 methodology is also presented

Absorption of nicotine and carbon monoxide from passive smoking under natural conditions of exposure.

Science.gov (United States)

Jarvis, M J; Russell, M A; Feyerabend, C

1983-01-01

Seven non-smokers were exposed to tobacco smoke under natural conditions for two hours in a public house. Measures of nicotine and cotinine in plasma, saliva, and urine and expired air carbon monoxide all showed reliable increases. The concentrations of carbon monoxide and nicotine after exposure averaged 15.7% and 7.5% respectively of the values found in heavy smokers. Although the increase in expired air carbon monoxide of 5.9 ppm was similar to increases in smokers after a single cigarette, the amount of nicotine absorbed was between a tenth and a third of the amount taken in from one cigarette. Since this represented a relatively extreme acute natural exposure, any health risks of passive smoking probably depend less on quantitative factors than on qualitative differences between sidestream and mainstream smoke. PMID:6648864

Steam oxidation of TP 347H FG. Laboratory exposures versus service conditions at the power plant

Energy Technology Data Exchange (ETDEWEB)

Hansson, Anette N. [DONG Energy A/S, Copenhagen (Denmark); Montgomery, Melanie [DONG Energy A/S, Copenhagen (Denmark); Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Mechanical Engineering; Vattenfall Heat Nordic, Copenhagen (Denmark)

2010-07-01

TP347H FG is often used as final superheater tubing at Danish Power Plants. The oxidation behaviour of TP347H FG in steam was investigated both in laboratory conditions and field conditions. Short time exposures (336 hours) were performed in the laboratory at 500, 600 and 700 C in gasses with 8 or 46% H{sub 2}O and varying oxygen partial pressures. The shortest exposure time at the power plant was 7720 h, the temperature varied between 500 and 650 C. Surprisingly, thicker oxide layers formed within the laboratory facility at 600 and 700 C than during the long time exposures at the power plant. This could not be explained by spallation. Double-layered oxides developed during oxidation. The outer layer consist of Fe-oxides and the inner oxide contained Fe and the remaining alloy elements. Investigations with scanning electron microscopy (SEM) revealed that the morphology of the inner oxide was different for the two types of exposures. However, investigation using transmission electron microscopy (TEM) showed that the inner oxide in both cases consisted of particles of Fe-Mn-Cr spinel embedded in a metallic Fe-Ni matrix in the bulk of the (former) alloy grains and Cr-rich oxide layer along the (former) alloy grain boundaries. The main difference between the layers formed at the two locations is that the Cr-rich oxide layer is thicker for the samples exposed at the power plant than that for the samples exposed at the laboratory conditions. Furthermore, the depth of Cr depletion in the alloy adjacent the oxide layer is greater for the samples exposed at the power plant compared to those exposed in the laboratory. The microstructure investigation suggests that the slower oxidation rate of TP347H FG at the power plant as compared to the laboratory is due to a larger reservoir of Cr for the samples exposed at the power plant probably combined with a higher mobility of Cr within the alloy. (orig.)

Effect of thermal exposure on the residual stress relaxation in a hardened cylindrical sample under creep conditions

Science.gov (United States)

Radchenko, V. P.; Saushkin, M. N.; Tsvetkov, V. V.

2016-05-01

This paper describes the effect of thermal exposure (high-temperature exposure) ( T = 675°C) on the residual creep stress relaxation in a surface hardened solid cylindrical sample made of ZhS6UVI alloy. The analysis is carried out with the use of experimental data for residual stresses after micro-shot peening and exposures to temperatures equal to T = 675°C during 50, 150, and 300 h. The paper presents the technique for solving the boundary-value creep problem for the hardened cylindrical sample with the initial stress-strain state under the condition of thermal exposure. The uniaxial experimental creep curves obtained under constant stresses of 500, 530, 570, and 600 MPa are used to construct the models describing the primary and secondary stages of creep. The calculated and experimental data for the longitudinal (axial) tensor components of residual stresses are compared, and their satisfactory agreement is determined.

Influence of test conditions and exposure duration on the result of ecotoxicological tests

DEFF Research Database (Denmark)

Rosenkrantz, Rikke Tjørnhøj

be calculated from results of ecotoxicological tests performed according to internationally approved guidelines, such as from the Organisation for Economic Co-operation and Development (OECD) or International Standardization Organisation (ISO). Such guidelines were originally developed to enable classification......H and exposure duration on the toxicity recorded in tests using four sulfonylurea herbicides (SUs) and the aquatic macrophyte Lemna gibba as study objects. The study showed that changing the physical and chemical test conditions influenced the toxicity of sulfonylurea herbicides towards L. gibba. Lowering...

In vitro exposure of human lung cells to emissions of several indoor air sources created in a climate chamber

NARCIS (Netherlands)

Bluyssen, P.M.; Alblas, M.J.; Tuinman, I.L.

2013-01-01

In the last decade, studies on indoor air pollution suggest a link between exposure to indoor particulate matter and compounds, in particular ultrafine particles and secondary organic aerosols, and several health effects. The mechanisms of how those complex mixtures relate to health effects are

Condition assessment of timber bridges. 2, Evaluation of several stress-wave tools

Science.gov (United States)

Brian K. Brashaw; Robert J. Vatalaro; James P. Wacker; Robert J. Ross

2005-01-01

This study was conducted to evaluate the accuracy and reliability of several stress-wave devices widely used for locating deteriorated areas in timber bridge members. Bridge components containing different levels of natural decay were tested using various devices. The specimens were then sawn (along their length) into slabs to expose their interior condition. The...

Severe, multimodal stress exposure induces PTSD-like characteristics in a mouse model of single prolonged stress.

Science.gov (United States)

Perrine, Shane A; Eagle, Andrew L; George, Sophie A; Mulo, Kostika; Kohler, Robert J; Gerard, Justin; Harutyunyan, Arman; Hool, Steven M; Susick, Laura L; Schneider, Brandy L; Ghoddoussi, Farhad; Galloway, Matthew P; Liberzon, Israel; Conti, Alana C

2016-04-15

Appropriate animal models of posttraumatic stress disorder (PTSD) are needed because human studies remain limited in their ability to probe the underlying neurobiology of PTSD. Although the single prolonged stress (SPS) model is an established rat model of PTSD, the development of a similarly-validated mouse model emphasizes the benefits and cross-species utility of rodent PTSD models and offers unique methodological advantages to that of the rat. Therefore, the aims of this study were to develop and describe a SPS model for mice and to provide data that support current mechanisms relevant to PTSD. The mouse single prolonged stress (mSPS) paradigm, involves exposing C57Bl/6 mice to a series of severe, multimodal stressors, including 2h restraint, 10 min group forced swim, exposure to soiled rat bedding scent, and exposure to ether until unconsciousness. Following a 7-day undisturbed period, mice were tested for cue-induced fear behavior, effects of paroxetine on cue-induced fear behavior, extinction retention of a previously extinguished fear memory, dexamethasone suppression of corticosterone (CORT) response, dorsal hippocampal glucocorticoid receptor protein and mRNA expression, and prefrontal cortex glutamate levels. Exposure to mSPS enhanced cue-induced fear, which was attenuated by oral paroxetine treatment. mSPS also disrupted extinction retention, enhanced suppression of stress-induced CORT response, increased mRNA expression of dorsal hippocampal glucocorticoid receptors and decreased prefrontal cortex glutamate levels. These data suggest that the mSPS model is a translationally-relevant model for future PTSD research with strong face, construct, and predictive validity. In summary, mSPS models characteristics relevant to PTSD and this severe, multimodal stress modifies fear learning in mice that coincides with changes in the hypothalamo-pituitary-adrenal (HPA) axis, brain glucocorticoid systems, and glutamatergic signaling in the prefrontal cortex

Antifouling effect of hydrogen peroxide release from enzymatic marine coatings: Exposure testing under equatorial and Mediterranean conditions

DEFF Research Database (Denmark)

Olsen, S.M.; Kristensen, J.B.; Laursen, B.S.

2010-01-01

Mediterranean and equatorial climatic conditions, is investigated. During seawater exposure of the coatings, starch is first converted to glucose by glucoamylase (rate-controlling step) and subsequently glucose is rapidly oxidised by hexose oxidase in a reaction producing hydrogen peroxide. The coatings...

Reports of Severe Physical Punishment and Exposure to Animal Cruelty by Inmates Convicted of Felonies and by University Students.

Science.gov (United States)

Miller, Karla S.; Knutson, John F.

1997-01-01

A self-report questionnaire designed to assess abusive childhood environments and exposure to animal cruelty was administered to 314 prison inmates. Although high rates of physical punishment characterized the entire sample, persons charged with violent but nonhomicidal crimes reported more severely punitive childhood histories than those charged…

Sex differences in the effects of ethanol pre-exposure during adolescence on ethanol-induced conditioned taste aversion in adult rats.

Science.gov (United States)

Sherrill, Luke K; Berthold, Claire; Koss, Wendy A; Juraska, Janice M; Gulley, Joshua M

2011-11-20

Alcohol use, which typically begins during adolescence and differs between males and females, is influenced by both the rewarding and aversive properties of the drug. One way adolescent alcohol use may modulate later consumption is by reducing alcohol's aversive properties. Here, we used a conditioned taste aversion (CTA) paradigm to determine if pre-exposure to alcohol (ethanol) during adolescence would attenuate ethanol-induced CTA assessed in adulthood in a sex-dependent manner. Male and female Long-Evans rats were given intraperitoneal (i.p.) injections of saline or 3.0g/kg ethanol in a binge-like pattern during postnatal days (PD) 35-45. In adulthood (>PD 100), rats were given access to 0.1% saccharin, followed by saline or ethanol (1.0 or 1.5g/kg, i.p.), over four conditioning sessions. We found sex differences in ethanol-induced CTA, with males developing a more robust aversion earlier in conditioning. Sex differences in the effects of pre-exposure were also evident: males, but not females, showed an attenuated CTA in adulthood following ethanol pre-exposure, which occurred approximately nine weeks earlier. Taken together, these findings indicate that males are more sensitive to the aversive properties of ethanol than females. In addition, the ability of pre-exposure to the ethanol US to attenuate CTA is enhanced in males compared to females. Copyright © 2011 Elsevier B.V. All rights reserved.

Exposure to severe urban air pollution influences cognitive outcomes, brain volume and systemic inflammation in clinically healthy children.

Science.gov (United States)

Calderón-Garcidueñas, Lilian; Engle, Randall; Mora-Tiscareño, Antonieta; Styner, Martin; Gómez-Garza, Gilberto; Zhu, Hongtu; Jewells, Valerie; Torres-Jardón, Ricardo; Romero, Lina; Monroy-Acosta, Maria E; Bryant, Christopher; González-González, Luis Oscar; Medina-Cortina, Humberto; D'Angiulli, Amedeo

2011-12-01

Exposure to severe air pollution produces neuroinflammation and structural brain alterations in children. We tested whether patterns of brain growth, cognitive deficits and white matter hyperintensities (WMH) are associated with exposures to severe air pollution. Baseline and 1 year follow-up measurements of global and regional brain MRI volumes, cognitive abilities (Wechsler Intelligence Scale for Children-Revised, WISC-R), and serum inflammatory mediators were collected in 20 Mexico City (MC) children (10 with white matter hyperintensities, WMH(+), and 10 without, WMH(-)) and 10 matched controls (CTL) from a low polluted city. There were significant differences in white matter volumes between CTL and MC children - both WMH(+) and WMH(-) - in right parietal and bilateral temporal areas. Both WMH(-) and WMH(+) MC children showed progressive deficits, compared to CTL children, on the WISC-R Vocabulary and Digit Span subtests. The cognitive deficits in highly exposed children match the localization of the volumetric differences detected over the 1 year follow-up, since the deficits observed are consistent with impairment of parietal and temporal lobe functions. Regardless of the presence of prefrontal WMH, Mexico City children performed more poorly across a variety of cognitive tests, compared to CTL children, thus WMH(+) is likely only partially identifying underlying white matter pathology. Together these findings reveal that exposure to air pollution may perturb the trajectory of cerebral development and result in cognitive deficits during childhood. Copyright © 2011 Elsevier Inc. All rights reserved.

Effects of long-term exposure of tuffs to high-level nuclear waste-repository conditions. Preliminary report

International Nuclear Information System (INIS)

Blacic, J.; Carter, J.; Halleck, P.; Johnson, P.; Shankland, T.; Andersen, R.; Spicochi, K.; Heller, A.

1982-02-01

Tests have been performed to explore the effects of extended exposure of tuffs from the southwestern portion of the Nevada Test Site to temperatures and pressures similar to those that will be encountered in a high-level nuclear waste repository. Tuff samples ranging from highly welded, nonzeolitized to unwelded, highly zeolitized varieties were subjected to temperatures of 80, 120, and 180 0 C; confining pressures of 9.7 and 19.7 MPa; and water-pore pressures of 0.5 to 19.7 MPa for durations of 2 to 6 months. The following basic properties were measured before and after exposure and compared: tensile strength, uniaxial compressive strength, grain density, porosity, mineralogy, permeability, thermal expansion, and thermal conductivity. Depending on rock type and exposure conditions, significant changes in ambient tensile strength, compressive strength, grain density, and porosity were measured. Mineralogic examination, permeability, and thermal property measurements remain to be completed

Growth Responses of Fish During Chronic Exposure of Metal Mixture under Laboratory Conditions

Directory of Open Access Journals (Sweden)

Saima Naz and Muhammad Javed

2013-07-01

Full Text Available Growth responses of five fish species viz. Catla catla, Labeo rohita, Cirrhina mrigala, Ctenopharyngodon idella and Hypophthalmichthys molitrix were determined, separately, under chronic exposure of binary mixture of metals (Zn+Ni at sub-lethal concentrations (1/3rd of LC50 for 12 weeks. Randomized complete block design (RCBD was followed to conduct this research work. The groups (10 fish each of Catla catla, Labeo rohita, Cirrhina mrigala, Ctenopharyngodon idella and Hypophthalmichthys molitrix having almost similar weights were investigated for their growth responses and metals bioaccumulation patterns in their body organs during chronic exposure of Zn+Ni mixture. The bioaccumulation of metals in the fish body organs viz. gills, liver, kidney, fins, bones, muscle and skin were also determined before and after growth trails under the stress of metals mixture. The exposure of fish to sub-lethal concentrations of mixture caused significant impacts on the average wet weight increments of five fish species. Ctenopharyngodon idella and Labeo rohita attained significantly higher weights, followed by that of Hypophthalmichthys molitrix, Cirrhina mrigala and Catla catla. However, the growth of metals mixture exposed fish species was significantly lesser than that of control fish (un-stressed. Significantly variable condition factor values reflected the degree of fish well-beings that correlated directly with fish growth and metal exposure concentration. Any significant change in feed intake, due to stress, is reflected in terms of fish growth showing the impacts of metal mixture on fish growth were either additive or antagonist / synergistic. Accumulation of all the metals in fish body followed the general order: liver>kidney>gills> skin >muscle> fins >bones.

Behavioral changes in response to sound exposure and no spatial avoidance of noisy conditions in captive zebrafish.

Science.gov (United States)

Neo, Yik Yaw; Parie, Lisa; Bakker, Frederique; Snelderwaard, Peter; Tudorache, Christian; Schaaf, Marcel; Slabbekoorn, Hans

2015-01-01

Auditory sensitivity in fish serves various important functions, but also makes fish susceptible to noise pollution. Human-generated sounds may affect behavioral patterns of fish, both in natural conditions and in captivity. Fish are often kept for consumption in aquaculture, on display in zoos and hobby aquaria, and for medical sciences in research facilities, but little is known about the impact of ambient sounds in fish tanks. In this study, we conducted two indoor exposure experiments with zebrafish (Danio rerio). The first experiment demonstrated that exposure to moderate sound levels (112 dB re 1 μPa) can affect the swimming behavior of fish by changing group cohesion, swimming speed and swimming height. Effects were brief for both continuous and intermittent noise treatments. In the second experiment, fish could influence exposure to higher sound levels by swimming freely between an artificially noisy fish tank (120-140 dB re 1 μPa) and another with ambient noise levels (89 dB re 1 μPa). Despite initial startle responses, and a brief period in which many individuals in the noisy tank dived down to the bottom, there was no spatial avoidance or noise-dependent tank preference at all. The frequent exchange rate of about 60 fish passages per hour between tanks was not affected by continuous or intermittent exposures. In conclusion, small groups of captive zebrafish were able to detect sounds already at relatively low sound levels and adjust their behavior to it. Relatively high sound levels were at least at the on-set disturbing, but did not lead to spatial avoidance. Further research is needed to show whether zebrafish are not able to avoid noisy areas or just not bothered. Quantitatively, these data are not directly applicable to other fish species or other fish tanks, but they do indicate that sound exposure may affect fish behavior in any captive condition.

Aircrew Exposure To Cosmic Radiation Evaluated By Means Of Several Methods; Results Obtained In 2006

International Nuclear Information System (INIS)

Ploc, Ondrej; Spurny, Frantisek; Jadrnickova, Iva; Turek, Karel

2008-01-01

Routine evaluation of aircraft crew exposure to cosmic radiation in the Czech Republic is performed by means of calculation method. Measurements onboard aircraft work as a control tool of the routine method, as well as a possibility of comparison of results measured by means of several methods. The following methods were used in 2006: (1) mobile dosimetry unit (MDU) type Liulin--a spectrometer of energy deposited in Si-detector; (2) two types of LET spectrometers based on the chemically etched track detectors (TED); (3) two types of thermoluminescent detectors; and (4) two calculation methods. MDU represents currently one of the most reliable equipments for evaluation of the aircraft crew exposure to cosmic radiation. It is an active device which measures total energy depositions (E dep ) in the semiconductor unit, and, after appropriate calibration, is able to give a separate estimation for non-neutron and neutron-like components of H*(10). This contribution consists mostly of results acquired by means of this equipment; measurements with passive detectors and calculations are mentioned because of comparison. Reasonably good agreement of all data sets could be stated

Assesment of Severely ASR Damaged Bridges: From Diagnosis to Structural Effects

DEFF Research Database (Denmark)

Barbosa, Ricardo Antonio; Hansen, Søren Gustenhoff; Hansen, Kurt Kielsgaard

2016-01-01

documented. The majority of the experimental data are based on relatively small scale laboratory specimens accelerated by various exposure conditions. Research on assessment and influence of severely ASR deterioration on the material properties and residual load carrying capacity of real-life structures...... is unfortunately limited. This paper presents an overview and discussion of the Danish experiences with assessment of the residual load carrying capacity of severely non-shear reinforced ASR damaged bridges. The discussion is supported by experimental data acquired from large scale in-situ tests of three severely...

Severe asthma in childhood

International Nuclear Information System (INIS)

Ciznar, P.

2013-01-01

Patients with severe asthma are clinically, physiologically and biologically a heterogeneous group. About half of children referred for medical examination for severe asthma have true severe, therapy resistant asthma. The rest of referred patients have difficult to treat asthma. Symptoms persist mostly due to drug non-compliance, inappropriate inhalation technique, persistent environmental exposures or co-morbid conditions. Compared with adults have children more frequently atopic form of severe asthma. This is associated with eosinophilia in peripheral blood and sensitization to inhaled allergens. The IgE levels are high. Therapy of co-morbidities and improvement of treatment compliance lead in most cases to full asthma control. Proportion of children will benefit from biologics like anti-IgE monoclonal antibody, administered by subcutaneous injections in 2 to 4 week intervals. By this therapy it is not only possible to suppress symptoms, but also decrease the total steroid dose and the risk of adverse effects associated with its long-term administration. By achieving a full asthma control we lower future risk of exacerbations and probably improve long-term prognosis of disease, frequently persisting for the rest of life. (author)

Heat wave exposure in India in current, 1.5 °C, and 2.0 °C worlds

Science.gov (United States)

Mishra, Vimal; Mukherjee, Sourav; Kumar, Rohini; Stone, Dáithí A.

2017-12-01

Heatwaves with large impacts have increased in the recent past and will continue to increase under future warming. However, the implication for population exposure to severe heatwaves remains unexplored. Here, we characterize maximum potential human exposure (without passive/active reduction measures) to severe heatwaves in India. We show that if the global mean temperature is limited to 2.0 °C above pre-industrial conditions, the frequency of severe heatwaves will rise by 30 times the current climate by the end-21st century. In contrast, the frequency is projected to be about 2.5 times more (than the low-warming scenario of 2 °C) under conditions expected if the RCP8.5 ‘business-as-usual’ emissions scenario is followed. Under the 2.0 °C low-warming target, population exposure to severe heatwaves is projected to increase by about 15 and 92 times the current level by the mid and end-21st century respectively. Strategies to reduce population growth in India during the 21st century may provide only limited mitigation of heatwave exposure mostly late in the century. Limiting global temperatures to 1.5 °C above preindustrial would reduce the exposure by half relative to RCP8.5 by the mid-21st century. If global temperatures are to exceed 1.5 °C then substantial measures will be required to offset the large increase in exposure to severe heatwaves in India.

Clinical significance of detection of serum markers of several viral infections in hospitalized patients before blood exposure

International Nuclear Information System (INIS)

Hong Kai; Chen Linxing; Chen Yichang; Ding Yingshu

2005-01-01

Objective: To explore the desirability of setting a routine of test for detection of the serum markers of several viral infections hospitalized patients before anticipated blood exposure. Methods: Serum levels of five HBV markers, anti-HCV, anti-HIV (with ELISA) and ALT were determined in 214 hospitalized patients before forthcoming blood exposure as well as in 2468 controls. Results: The positive rate of each of the above-mentioned markers in the patients was: HBsAg 15.2% (397/2614), HBcAb- IgG 72.5% (1895/2614), anti-HCV 3.91% (102/2614), anti- HIV 0.08% (2/2614) and ALT level was above 40 u in 8.7% of the patients (227/2614). Each of the positive rate was significantly higher than that in the controls. Conclusion: There is a substantial portion of subjects harboring viral infections in the hospitalized patients. It is imperative to have these patients identified before blood exposure so that proper cautions can be taken and preventive measures implemented to minimize possible nosocomial as well as patients-to-staff infections. Moreover, any potential legal problems can also be appropriately dealt with. (authors)

Perceived family social support buffers against the effects of exposure to rocket attacks on adolescent depression, aggression, and severe violence.

Science.gov (United States)

Shahar, Golan; Henrich, Christopher C

2016-02-01

The authors compared the protective effects of 3 sources of perceived social support-from family members, friends, and school personnel-on internalizing and externalizing symptoms in adolescents exposed to rocket attacks. Data were based on 362 Israeli adolescents (median age = 14), chronically exposed to rockets from the Gaza Strip, for whom robust effects of exposure on internalizing and externalizing symptoms were reported during the 2009-2010 period (Henrich & Shahar, 2013). New analyses revealed that perceived family social support assessed in 2009 buffered against the effect of exposure to rocket attacks on depression, aggression, and severe violence during 2009-2010. Findings are consistent with a human-ecological perspective exposure to political violence and encourage the employment of family-based preventive interventions in afflicted areas. (c) 2016 APA, all rights reserved).

Standard Practice for Exposure of Solar Collector Cover Materials to Natural Weathering Under Conditions Simulating Stagnation Mode

CERN Document Server

American Society for Testing and Materials. Philadelphia

1992-01-01

1.1 This practice covers a procedure for the exposure of solar collector cover materials to the natural weather environment at elevated temperatures that approximate stagnation conditions in solar collectors having a combined back and edge loss coefficient of less than 1.5 W/(m2 · °C). 1.2 This practice is suitable for exposure of both glass and plastic solar collector cover materials. Provisions are made for exposure of single and double cover assemblies to accommodate the need for exposure of both inner and outer solar collector cover materials. 1.3 This practice does not apply to cover materials for evacuated collectors, photovoltaic cells, flat-plate collectors having a combined back and edge loss coefficient greater than 1.5 W/(m2 ·° C), or flat-plate collectors whose design incorporates means for limiting temperatures during stagnation. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard t...

Severity of ASD symptoms and their correlation with the presence of copy number variations and exposure to first trimester ultrasound.

Science.gov (United States)

Webb, Sara Jane; Garrison, Michelle M; Bernier, Raphael; McClintic, Abbi M; King, Bryan H; Mourad, Pierre D

2017-03-01

Current research suggests that incidence and heterogeneity of autism spectrum disorder (ASD) symptoms may arise through a variety of exogenous and/or endogenous factors. While subject to routine clinical practice and generally considered safe, there exists speculation, though no human data, that diagnostic ultrasound may also contribute to ASD severity, supported by experimental evidence that exposure to ultrasound early in gestation could perturb brain development and alter behavior. Here we explored a modified triple hit hypothesis [Williams & Casanova, ] to assay for a possible relationship between the severity of ASD symptoms and (1) ultrasound exposure (2) during the first trimester of pregnancy in fetuses with a (3) genetic predisposition to ASD. We did so using retrospective analysis of data from the SSC (Simon's Simplex Collection) autism genetic repository funded by the Simons Foundation Autism Research Initiative. We found that male children with ASD, copy number variations (CNVs), and exposure to first trimester ultrasound had significantly decreased non-verbal IQ and increased repetitive behaviors relative to male children with ASD, with CNVs, and no ultrasound. These data suggest that heterogeneity in ASD symptoms may result, at least in part, from exposure to diagnostic ultrasound during early prenatal development of children with specific genetic vulnerabilities. These results also add weight to on-going concerns expressed by the FDA about non-medical use of diagnostic ultrasound during pregnancy. Autism Res 2017, 10: 472-484. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

Russian standards and design practice of ensuring NPP reliability under severe external loading conditions

Energy Technology Data Exchange (ETDEWEB)

Birbraer, A N [St. Petersburg Research and Design Institute Atomenergoproject, St. Petersburt (Russian Federation)

1993-07-01

Russian Standards and design practice of ensuring NPP reliability under severe external loading conditions are described. The main attention is paid to the seismic design requirements. Explosions, aircraft impact, and tornado are briefly examined too (author)

Russian standards and design practice of ensuring NPP reliability under severe external loading conditions

International Nuclear Information System (INIS)

Birbraer, A.N.

1993-01-01

Russian Standards and design practice of ensuring NPP reliability under severe external loading conditions are described. The main attention is paid to the seismic design requirements. Explosions, aircraft impact, and tornado are briefly examined too (author)

Sensorimotor difficulties are associated with the severity of autism spectrum conditions.

Directory of Open Access Journals (Sweden)

Penelope Hannant

2016-08-01

Full Text Available Present diagnostic criteria for autism spectrum conditions (ASC include social communication and interaction difficulties, repetitive behaviour and movement, and atypical sensory responsivity. Few studies have explored the influence of motor coordination and sensory responsivity on severity of ASC symptoms. In the current study, we explore whether sensory responsivity and motor coordination differences can account for the severity of autistic behaviours in children with ASC. 36 children took part: 18 (13 male, 5 female with ASC (ages 7-16: mean age 9.93 years and 18 (7 male, 11 female typically developing (TD children (ages 6-12; mean age 9.16 years. Both groups completed a battery of assessments that included motor coordination, sensory responsivity, receptive language, non-verbal reasoning and social communication measures Children with ASC also completed the Autism Diagnostic Observation Schedule and Autism Diagnostic Interview – Revised.. Results showed that children with ASC scored significantly lower on receptive language, coordination and sensory responsivity and a sensorimotor subscale, Modulation of Activity (MoA compared to the TD group. In the ASC group, MoA significantly predicted ASC severity across all ASC measures; receptive language and sensory responsivity significantly predicted parental reported autism measures; and coordination significantly predicted examiner observed reported scores. Additionally, specific associations were found between the somatosensory perceptive modalities and ASC severity. The results show that sensorimotor skills are associated with severity of ASC symptoms; furthering the need to research sensorimotor integration in ASC and also implying that diagnosis of ASC should also include the assessment of both coordination deficit and atypical sensory responsivity.

Subliminal mere exposure: specific, general, and diffuse effects.

Science.gov (United States)

Monahan, J L; Murphy, S T; Zajonc, R B

2000-11-01

The present research examined the possibility that repeated exposure may simultaneously produce specific and diffuse effects. In Study 1, participants were presented with 5-ms exposures of 25 stimuli each shown once (single-exposure condition) or with five repetitions of 5 stimuli (repeated-exposure condition). Participants in the repeated-exposure condition subsequently rated their own mood more positively than those in the single-exposure condition. Study 2 examined whether affect generated by subliminal repeated exposures transfers to unrelated stimuli. After a subliminal exposure phase, affective reactions to previously exposed stimuli, to new but similar stimuli, and to stimuli from a different category were obtained. Previously exposed stimuli were rated most positively and novel different stimuli least positively. All stimuli were rated more positively in the repeated-exposure condition than in the single-exposure condition. These findings suggest that affect generated by subliminal repeated exposure is sufficiently diffuse to influence ratings of unrelated stimuli and mood.

Aerosol exposure to Rift Valley fever virus causes earlier and more severe neuropathology in the murine model, which has important implications for therapeutic development.

Directory of Open Access Journals (Sweden)

Christopher Reed

Full Text Available Rift Valley fever virus (RVFV is an important mosquito-borne veterinary and human pathogen that can cause severe disease including acute-onset hepatitis, delayed-onset encephalitis, retinitis and blindness, or a hemorrhagic syndrome. Currently, no licensed vaccine or therapeutics exist to treat this potentially deadly disease. Detailed studies describing the pathogenesis of RVFV following aerosol exposure have not been completed and candidate therapeutics have not been evaluated following an aerosol exposure. These studies are important because while mosquito transmission is the primary means for human infection, it can also be transmitted by aerosol or through mucosal contact. Therefore, we directly compared the pathogenesis of RVFV following aerosol exposure to a subcutaneous (SC exposure in the murine model by analyzing survival, clinical observations, blood chemistry, hematology, immunohistochemistry, and virus titration of tissues. Additionally, we evaluated the effectiveness of the nucleoside analog ribavirin administered prophylactically to treat mice exposed by aerosol and SC. The route of exposure did not significantly affect the survival, chemistry or hematology results of the mice. Acute hepatitis occurred despite the route of exposure. However, the development of neuropathology occurred much earlier and was more severe in mice exposed by aerosol compared to SC exposed mice. Mice treated with ribavirin and exposed SC were partially protected, whereas treated mice exposed by aerosol were not protected. Early and aggressive viral invasion of brain tissues following aerosol exposure likely played an important role in ribavirin's failure to prevent mortality among these animals. Our results highlight the need for more candidate antivirals to treat RVFV infection, especially in the case of a potential aerosol exposure. Additionally, our study provides an account of the key pathogenetic differences in RVF disease following two potential

Memory enhancement produced by post-training exposure to sucrose-conditioned cues [v1; ref status: indexed, http://f1000r.es/ur

Directory of Open Access Journals (Sweden)

Matthew R Holahan

2013-01-01

Full Text Available A number of aversive and appetitive unconditioned stimuli (such as shock and food are known to produce memory enhancement when they occur during the post-training period. Post-training exposure to conditioned aversive stimuli has also been shown to enhance memory consolidation processes. The present study shows for the first time that post-training exposure to conditioned stimuli previously paired with consumption of a sucrose solution also enhances memory consolidation. Male Long Evans rats were trained on a one-session conditioned cue preference (CCP task on a radial arm maze. Immediately or 2 hours after training, rats consumed a sucrose solution or were exposed to cues previously paired with consumption of sucrose or cues previously paired with water. Twenty-four hours later, the rats were tested for a CCP. Immediate, but not delayed, post-training consumption of sucrose enhanced memory for the CCP. Immediate, but not delayed, post-training exposure to cues previously paired with sucrose, but not with water, also enhanced CCP memory. The possibility that rewarding and aversive conditioned stimuli affect memory by a common physiological process is discussed.

Standard Practice for Exposure of Cover Materials for Solar Collectors to Natural Weathering Under Conditions Simulating Operational Mode

CERN Document Server

American Society for Testing and Materials. Philadelphia

1995-01-01

1.1 This practice provides a procedure for the exposure of cover materials for flat-plate solar collectors to the natural weather environment at temperatures that are elevated to approximate operating conditions. 1.2 This practice is suitable for exposure of both glass and plastic solar collector cover materials. Provisions are made for exposure of single and double cover assemblies to accommodate the need for exposure of both inner and outer solar collector cover materials. 1.3 This practice does not apply to cover materials for evacuated collectors or photovoltaics. 1.4 The values stated in SI units are to be regarded as the standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Induction of enhanced acoustic startle response by noise exposure: dependence on exposure conditions and testing parameters and possible relevance to hyperacusis.

Directory of Open Access Journals (Sweden)

Rony H Salloum

Full Text Available There has been a recent surge of interest in the development of animal models of hyperacusis, a condition in which tolerance to sounds of moderate and high intensities is diminished. The reasons for this decreased tolerance are likely multifactorial, but some major factors that contribute to hyperacusis are increased loudness perception and heightened sensitivity and/or responsiveness to sound. Increased sound sensitivity is a symptom that sometimes develops in human subjects after acoustic insult and has recently been demonstrated in animals as evidenced by enhancement of the acoustic startle reflex following acoustic over-exposure. However, different laboratories have obtained conflicting results in this regard, with some studies reporting enhanced startle, others reporting weakened startle, and still others reporting little, if any, change in the amplitude of the acoustic startle reflex following noise exposure. In an effort to gain insight into these discrepancies, we conducted measures of acoustic startle responses (ASR in animals exposed to different levels of sound, and repeated such measures on consecutive days using a range of different startle stimuli. Since many studies combine measures of acoustic startle with measures of gap detection, we also tested ASR in two different acoustic contexts, one in which the startle amplitudes were tested in isolation, the other in which startle amplitudes were measured in the context of the gap detection test. The results reveal that the emergence of chronic hyperacusis-like enhancements of startle following noise exposure is highly reproducible but is dependent on the post-exposure thresholds, the time when the measures are performed and the context in which the ASR measures are obtained. These findings could explain many of the discrepancies that exist across studies and suggest guidelines for inducing in animals enhancements of the startle reflex that may be related to hyperacusis.

Filters from taxis air conditioning system: A tool to characterize driver's occupational exposure to bioburden?

Science.gov (United States)

Viegas, Carla; Monteiro, Ana; Dos Santos, Mateus; Faria, Tiago; Caetano, Liliana Aranha; Carolino, Elisabete; Quintal Gomes, Anita; Marchand, Geneviève; Lacombe, Nancy; Viegas, Susana

2018-07-01

Bioburden proliferation in filters from air conditioning systems of taxis represents a possible source of occupational exposure. The aim of this study was to determine the occurrence of fungi and bacteria in filters from the air conditioning system of taxis used for patient transportation and to assess the exposure of drivers to bioburden. Filters from the air conditioning systems of 19 taxis and 28 personal vehicles (used as controls) operating in three Portuguese cities including the capital Lisbon, were collected during the winter season. The occurrence and significance of bioburden detected in the different vehicles are reported and discussed in terms of colony-forming units (CFU) per 1 m 2 of filter area and by the identification of the most frequently detected fungal isolates based on morphology. Azole-resistant mycobiota, fungal biomass, and molecular detection of Aspergillus species/strains were also determined. Bacterial growth was more prevalent in taxis (63.2%) than in personal vehicles (26.3%), whereas fungal growth was more prevalent in personal vehicles (53.6%) than in taxis (21.1-31.6%). Seven different azole-resistant species were identified in this study in 42.1% taxi filters. Levels of fungal biomass were above the detection limit in 63% taxi filters and in 75% personal vehicle filters. No toxigenic species were detected by molecular analysis in the assessed filters. The results obtained show that bioburden proliferation occurs widely in filters from the air conditioning systems of taxis, including the proliferation of azole-resistant fungal species, suggesting that filters should be replaced more frequently. The use of culture based-methods and molecular tools combined enabled an improved risk characterization in this setting. Copyright © 2018 Elsevier Inc. All rights reserved.

Evaluation of external exposure during building and operation of concrete bridges constructions that reuse the conditionally released steels - 59120

International Nuclear Information System (INIS)

Panik, Michal; Necas, Vladimir

2012-01-01

This paper presents ongoing results of the project presented at ICEM'10 [1] related to the topics of reusing the conditionally released materials from decommissioning. The subject of the reuse of conditionally released materials in this case is modeling of bridge constructions which reuse the conditionally released steel in the form of reinforcement bars for the concrete bridges. A general approach for the project was presented at ICEM'10. The activities of the project continue in evaluating the individual effective doses from the external exposure based on reused conditionally released steels separately for public and for professionals (the internal exposure will be evaluated in next stages of the project). Evaluated scenarios are related to critical groups of professionals constructing the bridges (worker's scenarios). The computer code VISIPLAN 3D ALARA 4.0 planning tool was used for the calculation of the individual effective dose for professionals. Various limits of the annual individual effective dose are used for the evaluation of calculation results. The aim of the ongoing modeling is to develop a set of data of maximal radioactivity concentration for individual radionuclides in the conditionally released steel used in the bridges model constructions in order not to exceed the limits for the individual effective dose. (authors)

Evaluation of the leakage behavior of inflatable seals subject to severe accident conditions

International Nuclear Information System (INIS)

Parks, M.B.

1989-11-01

Sandia National Laboratories, under the sponsorship of the United States Nuclear Regulatory Commission, is currently developing test validated methods to predict the pressure capacity of light water reactor containment buildings when subjected to postulated severe accident conditions. These conditions are well beyond the design basis. Scale model tests of steel and reinforced concrete containments have been conducted as well as tests of typical containment penetrations. As a part of this effort, a series of tests was recently conducted to determine the leakage behavior of inflatable seals. These seals are used to prevent leakage around personnel and escape lock doors of some containments. The results of the inflatable seals tests are the subject of this report. Inflatable seals were tested at both room temperature and at elevated temperatures representative of postulated severe accident conditions. Both aged (radiation and thermal) and unaged seals were included in the test program. The internal seal pressure at the beginning of each test was varied to cover the range of seal pressures actually used in containments. For each seal pressure level, the external (containment) pressure was increased until significant leakage past the seals was observed. Parameters that were monitored and recorded during the tests were the internal seal pressure, chamber pressure, leakage past the seals, and temperature of the test chamber and fixture to which the seals were attached. 8 refs., 34 figs., 7 tabs

A Technique: Exposure Therapy

Directory of Open Access Journals (Sweden)

Serkan AKKOYUNLU

2013-07-01

Full Text Available Introduction: Exposure with response prevention is an effective treatment for all anxiety disorders. According to the behavioral learning theories, fears which are conditioned via classical conditioning are reinforced by respondent conditioning. Avoidance and safety seeking behaviors prevent disconfirmation of anxious beliefs. In exposure client faces stimulates or cues that elicit fear or distress, by this avoidance is inhibited. Clients are also encouraged to resists performing safety seeking behaviors or rituals that they utilize to reduce fear or distress. Accomplishing these habituation or extinction is achieved. In addition to this clients learn that feared consequences does not realize or not harmful as they believed by experiencing. Emotional processing is believed to be the mechanism of change in exposure.Objective: The aim of this review is to provide a definition of exposure and its effectiveness briefly, and describe how to implement exposure, its steps and remarkable aspects using. Exposure therapies and treatments that involve exposure are proved to be effective in all anxiety disorders. Exposure therapy can be divided in three parts: Assessment and providing a treatment rationale, creating an exposure hierarchy and response prevention plan, implementing exposure sessions. Clients must also continue to perform exposure between sessions. Therapy transcripts are also provided to exemplify these parts. Conclusion: Exposure with response prevention is a basic and effective technique. Every cognitive behavior therapist must be able to implement this technique and be cognizant of pearls of this procedure.

Oil spill cleanup in severe weather and open ocean conditions

International Nuclear Information System (INIS)

Kowalski, T.

1993-01-01

Most serious oil spills occur in open water under severe weather conditions. At first the oil stays on the surface, where it is spread by winds and water currents. The action of the waves then mixes the oil into the water column. With time the light elements of crude oil evaporate. The remaining residue is of very low commercial value, but of significant environmental impact. The oil spill can move either out to sea or inshore, where it ends up on the beaches. Normal procedures are to let outbound oil disperse by evaporation and mixing into the water column, and to let the inbound oil collect on the beaches, where the cleanup operations are concentrated. The reason for this is that there is no capability to clean the surface of the water in wave conditions-present-day oil skimmers are ineffective in waves approaching 4 ft in height. It would be simpler, more effective and environmentally more beneficial to skim the oil right at the spill location. This paper describes a method to do this. In the case of an oil spill in open water and high wave conditions, it is proposed to reduce the height of the ocean waves by the use of floating breakwaters to provide a relatively calm area. In such protected areas existing oil skimmers can be used to recover valuable oil and clean up the spill long before it hits the beaches. A floating breakwater developed at the University of Rhode Island by the author can be of great benefit in oil spill cleanup for open ocean conditions. This breakwater is constructed from scrap automobile tires. It is built in units of 20 tires each, which are easily transportable and can be connected together at the spill site to form any desired configuration

Exposures to Conditioned Flavours with Different Hedonic Values Induce Contrasted Behavioural and Brain Responses in Pigs

Science.gov (United States)

Clouard, Caroline; Jouhanneau, Mélanie; Meunier-Salaün, Marie-Christine; Malbert, Charles-Henri; Val-Laillet, David

2012-01-01

This study investigated the behavioural and brain responses towards conditioned flavours with different hedonic values in juvenile pigs. Twelve 30-kg pigs were given four three-day conditioning sessions: they received three different flavoured meals paired with intraduodenal (i.d.) infusions of 15% glucose (FGlu), lithium chloride (FLiCl), or saline (control treatment, FNaCl). One and five weeks later, the animals were subjected to three two-choice feeding tests without reinforcement to check the acquisition of a conditioned flavour preference or aversion. In between, the anaesthetised pigs were subjected to three 18FDG PET brain imaging coupled with an olfactogustatory stimulation with the conditioned flavours. During conditioning, the pigs spent more time lying inactive, and investigated their environment less after the FLiCl than the FNaCl or FGlu meals. During the two-choice tests performed one and five weeks later, the FNaCl and FGlu foods were significantly preferred over the FLICl food even in the absence of i.d. infusions. Surprisingly, the FNaCl food was also preferred over the FGlu food during the first test only, suggesting that, while LiCl i.d. infusions led to a strong flavour aversion, glucose infusions failed to induce flavour preference. As for brain imaging results, exposure to aversive or less preferred flavours triggered global deactivation of the prefrontal cortex, specific activation of the posterior cingulate cortex, as well as asymmetric brain responses in the basal nuclei and the temporal gyrus. In conclusion, postingestive visceral stimuli can modulate the flavour/food hedonism and further feeding choices. Exposure to flavours with different hedonic values induced metabolism differences in neural circuits known to be involved in humans in the characterization of food palatability, feeding motivation, reward expectation, and more generally in the regulation of food intake. PMID:22685528

Exposures to conditioned flavours with different hedonic values induce contrasted behavioural and brain responses in pigs.

Directory of Open Access Journals (Sweden)

Caroline Clouard

Full Text Available This study investigated the behavioural and brain responses towards conditioned flavours with different hedonic values in juvenile pigs. Twelve 30-kg pigs were given four three-day conditioning sessions: they received three different flavoured meals paired with intraduodenal (i.d. infusions of 15% glucose (F(Glu, lithium chloride (F(LiCl, or saline (control treatment, F(NaCl. One and five weeks later, the animals were subjected to three two-choice feeding tests without reinforcement to check the acquisition of a conditioned flavour preference or aversion. In between, the anaesthetised pigs were subjected to three (18FDG PET brain imaging coupled with an olfactogustatory stimulation with the conditioned flavours. During conditioning, the pigs spent more time lying inactive, and investigated their environment less after the F(LiCl than the F(NaCl or F(Glu meals. During the two-choice tests performed one and five weeks later, the F(NaCl and F(Glu foods were significantly preferred over the F(LICl food even in the absence of i.d. infusions. Surprisingly, the F(NaCl food was also preferred over the F(Glu food during the first test only, suggesting that, while LiCl i.d. infusions led to a strong flavour aversion, glucose infusions failed to induce flavour preference. As for brain imaging results, exposure to aversive or less preferred flavours triggered global deactivation of the prefrontal cortex, specific activation of the posterior cingulate cortex, as well as asymmetric brain responses in the basal nuclei and the temporal gyrus. In conclusion, postingestive visceral stimuli can modulate the flavour/food hedonism and further feeding choices. Exposure to flavours with different hedonic values induced metabolism differences in neural circuits known to be involved in humans in the characterization of food palatability, feeding motivation, reward expectation, and more generally in the regulation of food intake.

Exposures to conditioned flavours with different hedonic values induce contrasted behavioural and brain responses in pigs.

Science.gov (United States)

Clouard, Caroline; Jouhanneau, Mélanie; Meunier-Salaün, Marie-Christine; Malbert, Charles-Henri; Val-Laillet, David

2012-01-01

This study investigated the behavioural and brain responses towards conditioned flavours with different hedonic values in juvenile pigs. Twelve 30-kg pigs were given four three-day conditioning sessions: they received three different flavoured meals paired with intraduodenal (i.d.) infusions of 15% glucose (F(Glu)), lithium chloride (F(LiCl)), or saline (control treatment, F(NaCl)). One and five weeks later, the animals were subjected to three two-choice feeding tests without reinforcement to check the acquisition of a conditioned flavour preference or aversion. In between, the anaesthetised pigs were subjected to three (18)FDG PET brain imaging coupled with an olfactogustatory stimulation with the conditioned flavours. During conditioning, the pigs spent more time lying inactive, and investigated their environment less after the F(LiCl) than the F(NaCl) or F(Glu) meals. During the two-choice tests performed one and five weeks later, the F(NaCl) and F(Glu) foods were significantly preferred over the F(LICl) food even in the absence of i.d. infusions. Surprisingly, the F(NaCl) food was also preferred over the F(Glu) food during the first test only, suggesting that, while LiCl i.d. infusions led to a strong flavour aversion, glucose infusions failed to induce flavour preference. As for brain imaging results, exposure to aversive or less preferred flavours triggered global deactivation of the prefrontal cortex, specific activation of the posterior cingulate cortex, as well as asymmetric brain responses in the basal nuclei and the temporal gyrus. In conclusion, postingestive visceral stimuli can modulate the flavour/food hedonism and further feeding choices. Exposure to flavours with different hedonic values induced metabolism differences in neural circuits known to be involved in humans in the characterization of food palatability, feeding motivation, reward expectation, and more generally in the regulation of food intake.

Behavioural changes in response to sound exposure and no spatial avoidance of noisy conditions in captive zebrafish

Directory of Open Access Journals (Sweden)

Yik Yaw (Errol eNeo

2015-02-01

Full Text Available Auditory sensitivity in fish serves various important functions, but also makes fish susceptible to noise pollution. Human-generated sounds may affect behavioural patterns of fish, both in natural conditions and in captivity. Fish are often kept for consumption in aquaculture, on display in zoos and hobby aquaria, and for medical sciences in research facilities, but little is known about the impact of ambient sounds in fish tanks. In this study, we conducted two indoor exposure experiments with zebrafish (Danio rerio. The first experiment demonstrated that exposure to moderate sound levels (112 dB re 1 μPa can affect the swimming behaviour of fish by changing group cohesion, swimming speed and swimming height. Effects were brief for both continuous and intermittent noise treatments. In the second experiment, fish could influence exposure to higher sound levels by swimming freely between an artificially noisy fish tank (120-140 dB re 1 μPa and another with ambient noise levels (89 dB re 1 μPa. Despite initial startle responses, and a brief period in which many individuals in the noisy tank dived down to the bottom, there was no spatial avoidance or noise-dependent tank preference at all. The frequent exchange rate of about 60 fish passages per hour between tanks was not affected by continuous or intermittent exposures. In conclusion, small groups of captive zebrafish were able to detect sounds already at relatively low sound levels and adjust their behaviour to it. Relatively high sound levels were at least at the on-set disturbing, but did not lead to spatial avoidance. Further research is needed to show whether zebrafish are not able to avoid noisy areas or just not bothered. Quantitatively, these data are not directly applicable to other fish species or other fish tanks, but they do indicate that sound exposure may affect fish behaviour in any captive condition.

Seed vigour tests for predicting field emergence of maize under severe conditions

OpenAIRE

García de Yzaguirre, Álvaro; Lasa Dolhagaray, José Manuel

1989-01-01

[EN] With 40 to 50 different seed vigour tests available, appropiate procedures for choosing the best single test or combination the best predictors of seedling emergence of maize (Zea Mays L.) under severe conditions. Thirteen vigour tests and various field emergence trials were performed on six inbred lines and two commercial hybrids. The best single predictors of field emergence were identified by calculating simple correlation coefficients. The calculation of the geometric mean of the res...

Report of questionnaire concerning the conditions and exposure doses at thoracoabdominal radiography and CT

International Nuclear Information System (INIS)

2009-01-01

Japan Association of Radiological Technologists, at 2 years after its presentation of the Guideline for Medical Radiation Exposure (2006), made a questionnaire in the title on its homepage on Nov. 6-Dec. 5, 2008, and this paper is its report. The questionnaire asked the conditions and exposure doses at thoracoabdominal radiography and CT: in the former, asked were conditions like the machine/detector, tube voltage, filter, incident angle, entrance plane dose (EPD) (mGy) etc., and 237 facilities including 56 public hospitals and 15 universities answered. EPD calculated by numerical dose determination was found to be 0.22 and 0.76 mGy at the frontal and lateral thoracic projection, respectively, which were less than the upper limit defined in International Atomic Energy Agency (IAEA) guidance (0.4 and 1.5 mGy). However, doses in 6 and 2.6% of facilities at the respective projection exceeded the IAEA levels. EPD at the frontal abdominal projection calculated was 2.22 mGy, and all facilities met with the IAEA demand level (<10 mGy). In the CT questionnaire, conditions asked were the machine manufacturer/brand, scanning mode and range, tube voltage, rotation time, beam width and pitch, slice width, CTDIvol (CT Dose Index weighted/pitch) (mGy) and so on, which 212 facilities involving 58 public hospitals and 14 universities answered. CTDIvol was found to be 91.7 mGy at head CT which greatly exceeded the maximal levels of International Commission of Radiological Protection (ICRP), IAEA and the Association (60, 50 and 65 mGy, respectively). CTDIvol at thoracic CT was 15.2 mGy (no standard upper limit at present), and at abdominal CT, 20.0 mGy (the same as the Association level). The latter suggested the suitable dose setting at this CT. Thus the problem at head CT was much highlighted here. (K.T.)

Experimental results from containment piping bellows subjected to severe accident conditions. Volume 1, Results from bellows tested in 'like-new' conditions

International Nuclear Information System (INIS)

Lambert, L.D.; Parks, M.B.

1994-09-01

Bellows are an integral part of the containment pressure boundary in nuclear power plants. They are used at piping penetrations to allow relative movement between piping and the containment wall, while minimizing the load imposed on the piping and wall. Piping bellows are primarily used in steel containments; however, they have received limited use in some concrete (reinforced and prestressed) containments. In a severe accident they may be subjected to pressure and temperature conditions that exceed the design values, along with a combination of axial and lateral deflections. A test program to determine the leak-tight capacity of containment penetration bellows is being conducted under the sponsorship of the US Nuclear Regulatory Commission at Sandia National Laboratories. Several different bellows geometries, representative of actual containment bellows, have been subjected to extreme deflections along with pressure and temperature loads. The bellows geometries and loading conditions are described along with the testing apparatus and procedures. A total of thirteen bellows have been tested, all in the 'like-new' condition. (Additional tests are planned of bellows that have been subjected to corrosion.) The tests showed that bellows are capable of withstanding relatively large deformations, up to, or near, the point of full compression or elongation, before developing leakage. The test data is presented and discussed

Early life stress in rats sex-dependently affects remote endocrine rather than behavioral consequences of adult exposure to contextual fear conditioning.

Science.gov (United States)

Fuentes, Sílvia; Daviu, Núria; Gagliano, Humberto; Belda, Xavier; Armario, Antonio; Nadal, Roser

2018-05-30

Exposure to electric foot-shocks can induce in rodents contextual fear conditioning, generalization of fear to other contexts and sensitization of the hypothalamic-pituitary-adrenal (HPA) axis to further stressors. All these aspects are relevant for the study of post-traumatic stress disorder. In the present work we evaluated in rats the sex differences and the role of early life stress (ELS) in fear memories, generalization and sensitization. During the first postnatal days subjects were exposed to restriction of nesting material along with exposure to a "substitute" mother. In the adulthood they were exposed to (i) a contextual fear conditioning to evaluate long-term memory and extinction and (ii) to a novel environment to study cognitive fear generalization and HPA axis heterotypic sensitization. ELS did not alter acquisition, expression or extinction of context fear conditioned behavior (freezing) in either sex, but reduced activity in novel environments only in males. Fear conditioning associated hypoactivity in novel environments (cognitive generalization) was greater in males than females but was not specifically affected by ELS. Although overall females showed greater basal and stress-induced levels of ACTH and corticosterone, an interaction between ELS, shock exposure and sex was found regarding HPA hormones. In males, ELS did not affect ACTH response in any situation, whereas in females, ELS reduced both shock-induced sensitization of ACTH and its conditioned response to the shock context. Also, shock-induced sensitization of corticosterone was only observed in males and ELS specifically reduced corticosterone response to stressors in males but not females. In conclusion, ELS seems to have only a minor impact on shock-induced behavioral conditioning, while affecting the unconditioned and conditioned responses of HPA hormones in a sex-dependent manner. Copyright © 2018. Published by Elsevier Inc.

Short-term effect of severe exposure to methylmercury on atherosclerotic heart disease and hypertension mortality in Minamata.

Science.gov (United States)

Inoue, Sachiko; Yorifuji, Takashi; Tsuda, Toshihide; Doi, Hiroyuki

2012-02-15

Recent studies suggest potential adverse effects of methylmercury exposure on myocardial infarction and hypertension, although the evidence is still limited. We thus evaluated this association using age-standardized mortality ratios (ASMRs) in Minamata, where severe methylmercury poisoning had occurred. We obtained mortality data from annual vital statistics and demographic statistics from census. We then compared mortality of atherosclerotic heart disease including degenerative heart disease and hypertension in Minamata-city with those in Kumamoto Prefecture, which includes Minamata city, as a control. We estimated ASMRs and 95% confidence intervals (CIs) during the period from 1953 to 1970. ASMRs of atherosclerotic heart disease were continuously decreased during the period from 1953 to 1967. In contrast, the ASMR of hypertension was significantly elevated during the period from 1963 to 1967 (SMR=1.38, CI; 1.06-1.80); but they decreased later. Although dilution is present in this ecological study, our study supports the notion that methylmercury exposure induces hypertension. Copyright © 2011 Elsevier B.V. All rights reserved.

Evolution of the sensor fish device for measuring physical conditions in sever hydraulic environments

Energy Technology Data Exchange (ETDEWEB)

Carlson, Thomas J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Duncan, J. P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2003-03-01

To assist in deriving biological specifications for design of turbine rehabilitation measures, new “fish-friendly” turbines, and spillway designs and operations, Pacific Northwest National Laboratory (PNNL) scientists have developed and tested an autonomous multi-sensor device called a Sensor Fish that can acquire pressure and tri-axial linear acceleration data during passage through severe hydraulic conditions. The purpose of the Sensor Fish is to characterize physical conditions fish experience during passage through hydro turbines, spill stilling basins, high-discharge outfalls, and other dam passage routes. This report discusses the development and field tests of the Sensor Fish at Rock Island, McNary, The Dalles, Bonneville, and Wanapum dams on the Columbia River and the Prosser Irrigation District on the Yakima River, which have shown that the device can withstand the severe environments of turbine, spill, and fish bypass passage and provide useful environmental data that can ultimately aid in the design and operation of new and existing turbines, spill, and dam fish bypass facilities.

Antioxidant and oxidative stress parameters in brain of Heteropneustes fossilis under air exposure condition; role of mitochondrial electron transport chain.

Science.gov (United States)

Paital, Biswaranjan

2013-09-01

Many fishes are exposed to air in their natural habitat or during their commercial handling. In natural habitat or during commercial handling, the cat fish Heteropneustes fossilis is exposed to air for >24h. Data on its oxidative metabolism in the above condition are not available. Oxidative stress (OS) indices (lipid and protein oxidation), toxic reactive oxygen species (ROS: H2O2) generation, antioxidative status (levels of superoxide dismutase, catalase, glutathione peroxidase and reductase, ascorbic acid and non-protein sulfhydryl) and activities of electron transport chain (ETC) enzymes (complex I-IV) were investigated in brain tissue of H. fossilis under air exposure condition (0, 3, 6, 12 and 18 h at 25°C). Decreased activities of antioxidant (except catalase) and ETC enzymes (except complex II) with increased H2O2 and OS levels were observed in the tissue under water deprivation condition. Positive correlation was observed for complex II activity and non-protein thiol groups with time period of air exposure. The critical time period to induce OS and to reduce most of the studied antioxidant level in brain was found to be 3-6h air exposure. The data can be useful to minimize the stress generated during commercial handling of the live fishes those exposed to air in general and H. fossilis in particular. Copyright © 2013 Elsevier Inc. All rights reserved.

Intraperitoneal exposure of whitefish to microcystin-LR induces rapid liver injury followed by regeneration and resilience to subsequent exposures

International Nuclear Information System (INIS)

Woźny, Maciej; Lewczuk, Bogdan; Ziółkowska, Natalia; Gomułka, Piotr; Dobosz, Stefan; Łakomiak, Alicja; Florczyk, Maciej; Brzuzan, Paweł

2016-01-01

To date, there has been no systematic approach comprehensively describing the sequence of pathological changes in fish during prolonged exposure to microcystin-LR (MC-LR). Towards this aim, juvenile whitefish individuals received an intraperitoneal injection with pure MC-LR, and the injection was repeated every week to maintain continuous exposure for 28 days. During the exposure period, growth and condition of the fish were assessed based on biometric measurements. Additionally, selected biochemical markers were analysed in the fishes' blood, and their livers were carefully examined for morphological, ultrastructural, and molecular changes. The higher dose of MC-LR (100 μg·kg −1 ) caused severe liver injury at the beginning of the exposure period, whereas the lower dose (10 μg·kg −1 ) caused less, probably reversible injury, and its effects began to be observed later in the exposure period. These marked changes were accompanied by substantial MC-LR uptake by the liver. However, starting on the 7th day of exposure, cell debris began to be removed by phagocytes, then by 14th day, proliferation of liver cells had markedly increased, which led to reconstruction of the liver parenchyma at the end of the treatment. Surprisingly, despite weekly-repeated intraperitoneal injections, MC-LR did not accumulate over time of exposure which suggests its limited uptake in the later phase of exposure. In support, mRNA expression of the membrane transport protein oatp1d was decreased at the same time as the regenerative processes were observed. Our study shows that closing of active membrane transport may serve as one defence mechanism against further MC-LR intoxication. - Highlights: • The study presents pathological changes in whitefish during prolonged MC-LR exposure. • After early, severe injury, the damaged liver parenchyma of the fish regenerated. • Endoplasmic reticulum, cytoskeleton, and chromatin were the main targets for MC-LR. • MC-LR did not

Limit strains for severe accident conditions. Final report of the EU-project LISSAC

International Nuclear Information System (INIS)

Krieg, R.; Seidenfuss, M.

2003-10-01

The local failure strains of essential reactor vessel components are investigated. The size influence of the components is of special interest. Typical severe accident conditions including elevated temperatures and dynamic loads are considered. The main part of work consists of test families with specimens under uniaxial and biaxial static and dynamic loads. Within one test family the specimen geometries and the load conditions are similar, the temperature is the same; but the size is varied up to reactor dimensions. Special attention is given to geometries with a hole or a notch causing non-uniform stress and strain distributions typical for reactor components. There are indications that for such non-uniform distributions size effects may be stronger than for uniform distributions. Thus size effects on the failure strains and failure processes are determined under realistic conditions. Several tests with nominal identical parameters are performed for small size specimens. In this way some information is obtained about the scatter. A reduced number of tests is carried out for medium size specimens and only a few tests are carried out for large size specimens to reduce the costs to an acceptable level. To manufacture all specimens sufficient material was available from the unused reactor pressure vessel Biblis C consisting of the material 22NiMoCr37. Thus variations of the mechanical material properties, which could impair the interpretation of the test results, are quite small. This has been confirmed by an adequate number of additional quality assurance tests. A key problem was the definition of failure and the determination of the local strains at failure for very different specimens under varying load conditions. Here appropriate methods had to be developed including the so-called 'vanishing gap method' and the 'forging die method'. They are based on post test geometrical measurements of the fracture surfaces and reconstructions of the related strain fields

Modeling and Forecasting the Onset and Duration of Severe Radiation Fog under Frost Conditions

NARCIS (Netherlands)

Velde, van der I.R.; Steeneveld, G.J.; Wichers Schreur, B.G.J.; Holtslag, A.A.M.

2010-01-01

A case of a severe radiation fog during frost conditions is analyzed as a benchmark for the development of a very high resolution NWP model. Results by the Weather Research and Forecasting model (WRF) and the High resolution limited area model (HIRLAM) are evaluated against detailed observations to

Effects of cadmium on life-cycle parameters in a multi-generation study with Chironomus riparius following a pre-exposure of populations to two different tributyltin concentrations for several generations.

Science.gov (United States)

Vogt, Christian; Hess, Maren; Nowak, Carsten; Diogo, João Barateiro; Oehlmann, Jörg; Oetken, Matthias

2010-10-01

So far only a few studies have been performed to assess the effects of dynamic pollutant exposure on life-history parameters of invertebrates. In a previous multi-generation approach with the midge Chironomus riparius we tested if a chronic tributyltin pre-exposure alters the ability of a population to cope with subsequent cadmium stress. In the experiment two separate chironomid populations were exposed via sediments to different TBT-concentrations (4.46 and 8.93 μg Sn/kg dw) for several generations, followed by subsequent cadmium exposure (1.2 mg Cd/kg dw) for three generations. While the TBT-exposure to 4.46 μg Sn/kg dw had only small effects on the development and reproduction of C. riparius the higher TBT-concentration of 8.93 μg Sn/kg dw led to negative effects on life-history traits. Therefore, a higher adverse effect of the higher TBT-concentration and thus a higher susceptibility to other stressors could be assumed. Within, this paper only the results of the second stressor experiment were presented; clear effects of Cd on development and reproduction of C. riparius were determined independent of the pre-exposure scenario. While no differences in Cd-sensitivity were found between the population without pre-exposure to TBT and the population pre-exposed to the low TBT-concentration (4.46 μg Sn/kg dw), the pre-exposure of midges to the higher TBT-concentration (8.93 μg Sn/kg dw) resulted in a significantly higher susceptibility to subsequent Cd-stress. These results document that the exposure history may influence the reaction to altered chemical stress. Our findings are relevant to understand and predict the evolutionary fate of populations in rapidly changing, human-impacted environments. However, the fact that chemical-induced reduced genetic diversity, which is not necessarily linked to genetic adaptation, leads to a reduced fitness under altered stress conditions, is to our knowledge a novel finding.

influence of severe conditions on the concrete employed in nuclear technology

International Nuclear Information System (INIS)

Khalil, W.M.K.S.

2006-01-01

this thesis is mainly concentrating on honing the efficiency of heavy-weight high -performance (HWHP) concrete, developed from local aggregates together with additives that are waste products of other manufacturing processes, for the purpose of producing radiation shields, to attenuate gamma-rays in peaceful active-service facilitations . in other words, the thesis is in attempt to develop a special type of heavy concrete of various advantages that would enhance its performance in severe environment. such advantages may embrace concurrent improvements; such as high specific gravity, workability, high compressive strength, efficient attenuator for gamma radiation, and resistant to elevated temperature along with chemical attack.the named HWHP concrete was mainly prepared using two types of heavy aggregates, ilmenite (iron ore) and barite . in addition usual concrete (dolomite/sand) was also employed in this thesis to compare the obtained HWHP concrete. the practical facet of this thesis accounts for evaluating the influence of severe conditions, concomitantly and consecutively, on mechanical , morphological and attenuation characteristics for the three types of concrete

Modelling of Zircaloy-steam-oxidation under severe fuel damage conditions

International Nuclear Information System (INIS)

Malang, S.; Neitzel, H.J.

1983-01-01

Small break loss-of-coolant accidents and special transients in an LWR, in combination with loss of required safety systems, may lead to an uncovered core for an extended period of time. As a consequence, the cladding temperature could rise up to the melting point due to the decay heat, resulting in severely damaged fuel rods. During heat-up the claddings oxidize due to oxygen uptake from the steam atmosphere in the core. The modeling and assessment of the Zircaloy-steam oxidation under such conditions is important, mainly for two reasons: The oxidation of the cladding influences the temperature transients due to the exothermic heat of reaction; the amount of liquified fuel depends on the oxide layer thickness and the oxygen content of the remaining Zircaloy metal when the melting point is reached. (author)

Bias from conditioning on live birth in pregnancy cohorts: an illustration based on neurodevelopment in children after prenatal exposure to organic pollutants

Science.gov (United States)

Liew, Zeyan; Olsen, Jørn; Cui, Xin; Ritz, Beate; Arah, Onyebuchi A

2015-01-01

Only 60–70% of fertilized eggs may result in a live birth, and very early fetal loss mainly goes unnoticed. Outcomes that can only be ascertained in live-born children will be missing for those who do not survive till birth. In this article, we illustrate a common bias structure (leading to ‘live-birth bias’) that arises from studying the effects of prenatal exposure to environmental factors on long-term health outcomes among live births only in pregnancy cohorts. To illustrate this we used prenatal exposure to perfluoroalkyl substances (PFAS) and attention-deficit/hyperactivity disorder (ADHD) in school-aged children as an example. PFAS are persistent organic pollutants that may impact human fecundity and be toxic for neurodevelopment. We simulated several hypothetical scenarios based on characteristics from the Danish National Birth Cohort and found that a weak inverse association may appear even if PFAS do not cause ADHD but have a considerable effect on fetal survival. The magnitude of the negative bias was generally small, and adjusting for common causes of the outcome and fetal loss can reduce the bias. Our example highlights the need to identify the determinants of pregnancy loss and the importance of quantifying bias arising from conditioning on live birth in observational studies. PMID:25604449

Determination of a Quantitative Job Severity Score Value for Health Hazards in Industry

Directory of Open Access Journals (Sweden)

A. Nayebzadeh

2007-09-01

Full Text Available Background and aims   There are numerous types of health hazards in every workplace which threaten the health and well-being of employees. Therefore, various types of engineering and  administrative control approaches have been developed in industry. Control of hazardous agents can be difficult in most conditions due to economical and technical limitations. However, certain types of administrative control methods can be implemented in these cases instead of engineering or process controls. Since creating a safe environment with zero chance of occupational exposures to hazardous agents is practically impossible, it can be expected that every employee may have a certain level of exposure to one or more of hazardous agents. The probability and extent of these  exposures will depend on job's demands or work environment's conditions. Under this condition,  a "job severity score" as a quantitative value can be determined in order to choose and employ the  best possible control methodology and also to create a long-term occupational health plan.   Methods   In this study, the main goal is to develop a questionnaire as a model for assessment of job severity and tasks harmfulness. This questionnaire has five sections in which there are numbers  of questions each with a specified quantitative score.  These scores have been identified according to the brainstorming among the some experienced  experts in the fields safety, occupational health, and industrial psychology. When the final  questionnaire was completed, two well-known industrial sectors were selected as pilot plants for final verification of questionnaire in order to obtain valid questions.    Results & Conclusion   The result of this study was providing a questionnaire which might be used in similar studies for determination of job severity level at any industrial plants.

Effects of dietary exposure to brominated flame retardant BDE-47 on thyroid condition, gonadal development and growth of zebrafish

Science.gov (United States)

Torres, Leticia; Orazio, Carl E.; Peterman, Paul H.; Patino, Reynaldo

2013-01-01

Little is known about the effects of brominated flame retardants in teleosts and some of the information currently available is inconsistent. This study examined effects of dietary exposure to 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) on thyroid condition, body mass and size, and gonadal development of zebrafish. Pubertal, 49-day-old (posthatch) fish were fed diets without BDE-47 (control) or with 1, 5 or 25 μg/g BDE-47/diet. Treatments were conducted in triplicate 30-L tanks each containing 50 zebrafish, and 15 fish per treatment (5 per tank) were sampled at days 40, 80 and 120 of exposure. Measurements were taken of body mass, standard length, head depth and head length. Sex (at 40–120 days of exposure), germ cell stage (at 40 days) and thyroid condition (at 120 days; follicular cell height, colloid depletion, angiogenesis) were histologically determined. Whole-body BDE-47 levels at study completion were within the high end of levels reported in environmentally exposed (wild) fishes. Analysis of variance was used to determine differences among treatments at each sampling time. No effects were observed on thyroid condition or germ cell stage in either sex. Reduced head length was observed in females exposed to BDE-47 at 80 days but not at 40 or 120 days. In males, no apparent effects of BDE-47 were observed at 40 and 80 days, but fish exposed to 25 μg/g had lower body mass at 120 days compared to control fish. These observations suggest that BDE-47 at environmentally relevant whole-body concentrations does not affect thyroid condition or pubertal development of zebrafish but does affect growth during the juvenile-to-adult transition, especially in males.

The impact of environmental conditions on human performance: A critical review of the literature. Volume 2

International Nuclear Information System (INIS)

Echeverria, D.; Barnes, V.; Bittner, A.

1994-09-01

The Battelle Human Affairs Research Centers (HARC) conducted a comprehensive review of the technical literature regarding the impact of environmental conditions on human performance applicable to nuclear power plant workers. The environmental conditions considered were vibration, noise, heat, cold, and light. Research staff identified potential human performance deficits along a continuum of increasing occupational exposure, ranging from deficits that occur at low exposures to deficits that occur at high exposures. Specific deficits were included in the review if scientists demonstrated the exposure caused an effect, using sound methodology. The levels associated with each deficit were then compared to the protection afforded by existing occupational exposure standards. Volume 2 presents several conclusions regarding the applicability of the research literature to environmental conditions in nuclear power plants. The findings presented suggest that occupational standards for vibration, noise, and heat, which were developed to protect health, are inadequate for preventing deficits in cognitive or motor performance in tasks likely to be performed in nuclear power plants. Also, there is little information in the literature on simultaneous conditions; for example, the effects of simultaneous exposure to heat and noise on cognition require more research. As many exposures in nuclear power plants will be simultaneous, this limitation should be kept in mind when using Volume 1

Modeling and Forecasting the Onset and Duration of Severe Radiation Fog under Frost Conditions

NARCIS (Netherlands)

van der Velde, I. R.; Steeneveld, G. J.; Schreur, B. G. J. Wichers; Holtslag, A. A. M.

2010-01-01

A case of a severe radiation fog during frost conditions is analyzed as a benchmark for the development of a very high-resolution NWP model Results by the Weather Research and Forecasting model (WRF) and the High Resolution Limited Area Model (H I RLAM) are evaluated against detailed observations to

Estimated consequences from severe spent nuclear fuel transportation accidents

International Nuclear Information System (INIS)

Arnish, J.J.; Monette, F.; LePoire, D.; Biwer, B.M.

1996-01-01

The RISKIND software package is used to estimate radiological consequences of severe accident scenarios involving the transportation of spent nuclear fuel. Radiological risks are estimated for both a collective population and a maximally exposed individual based on representative truck and rail cask designs described in the U.S. Nuclear Regulatory Commission (NRC) modal study. The estimate of collective population risk considers all possible environmental pathways, including acute and long-term exposures, and is presented in terms of the 50-y committed effective dose equivalent. Radiological risks to a maximally exposed individual from acute exposure are estimated and presented in terms of the first year and 50-y committed effective dose equivalent. Consequences are estimated for accidents occurring in rural and urban population areas. The modeled pathways include inhalation during initial passing of the radioactive cloud, external exposure from a reduction of the cask shielding, long-term external exposure. from ground deposition, and ingestion from contaminated food (rural only). The major pathways and contributing radionuclides are identified, and the effects of possible mitigative actions are discussed. The cask accident responses and the radionuclide release fractions are modeled as described in the NRC modal study. Estimates of severe accident probabilities are presented for both truck and rail modes of transport. The assumptions made in this study tend to be conservative; however, a set of multiplicative factors are identified that can be applied to estimate more realistic conditions

Fetal and infant exposure to severe Chinese famine increases the risk of adult dyslipidemia: Results from the China health and retirement longitudinal study

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Zhenghe Wang

2017-06-01

Full Text Available Abstract Background To explore the associations between the Chinese famine exposure in early life and the dyslipidemia in adulthood. Methods We selected 2752 participants from the baseline survey of China Health and Retirement Longitudinal Study (CHARLS 2011–2012 to evaluate the associations of early life the Chinese famine exposure with risk of dyslipidemia in adulthood. Dyslipidemia was defined as TC (Total Cholesterol: HDL-C (High-Density Lipoprotein Cholesterol ratio ≥ 5.0 or use cholesterol lowering drugs. Famine exposure cohorts were categorized by birthdates of participants. Binary logistics regression model was used to examine the associations of early-life famine exposure with the risk of dyslipidemia. Results The dyslipidemia prevalence of the non-exposed cohort, fetal stage-, infant stage-, and preschool stage-exposed cohorts in adulthood was 15.7%, 23.1%, 22.0%, and 18.6%, respectively. Early-life exposure to the Chinese famine significantly increased LDL cholesterol concentrations in adulthood after adjusted for age. The risks of dyslipidemia in fetal (OR = 1.58; 95% CI: 1.23–2.03; P < 0.001 and infant (OR = 1.52; 95% CI: 1.15–2.00; P = 0.003 stage-exposed cohorts were significantly higher than the non-exposed cohort after adjusted for gender and current family economic status. Following gender stratification, we found that fetal (OR = 1.80; 95% CI: 1.26–2.57; P = 0.001, infant (OR = 1.75; 95% CI: 1.17–2.62; P = 0.006, and preschool (OR = 1.63; 95% CI: 1.10–2.42; P = 0.015 -stage exposure to severe famine aggravated the risk of dyslipidemia in female adults. However, the similar association was not observed for male adults. Conclusions Early-life exposure to severe Chinese famine could link with the higher dyslipidemia risk in female adulthood, but not in male adulthood. This gender-specific effect might be associated with the hypothesis that parents in China prefer boys to girls traditionally or

Analysis of the behaviour of the Kozloduy NPP Unit 3 under severe accident conditions

International Nuclear Information System (INIS)

Velev, V.; Saraeva, V.

2004-01-01

The objective of the analysis is to study the behaviour of the Kozloduy NPP Unit 3 under severe accident conditions. The analysis is performed using computer code MELCOR 1.8.4. This report includes a brief description of Unit 3 active core as well as description and comparison of the key events

Environmental and Personal Factors Related to Asthma Severity among Children: Hospital Based Study, Egypt

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Omaima Ibrahim AboElkheir

2016-09-01

Full Text Available Background: Childhood asthma is a complex disorder in which many environmental and personal factors play a role. However, the contribution of these factors to asthma severity is poorly understood. This study aims to determine the relationship between environmental exposures, personal factors and asthma severity among asthmatic children. Methods: This cross-sectional hospital based study was conducted on 180 asthmatic children; they were divided into mild, moderate and severe asthma according to forced expiratory volume in first second. Environmental factors (indoor and outdoor, food allergy, history of other allergic diseases, family history of allergic disorders, time trend of attacks as well as asthma outcome were reported. Results: Children with severe asthma were younger than those with mild or moderate asthma. Severe asthma was significantly linked to family history of allergy, presence of co-morbid allergic diseases, fish, egg and milk allergy, as well as exposure to passive smoking (73.7% and poor housing conditions. Also, it was significantly linked to presence of unauthorized factories in residential area (31.6 %, p=0.001. As well as, contact with pets (42.1%. Children with severe asthma had more limitations of physical activities (73.7%, missed school days (81.5%, with poor school performance (p=0.04 than those with mild moderate or asthma. Conclusion: Severe asthma was linked to female gender and younger age, co-morbid allergic diseases, family history of atopy and food allergy. It was higher among children residing in places with unauthorized factories and living in substandard housing condition. Children with severe asthma had poor asthma outcome.

Interaction of radionuclides in severe accident conditions

International Nuclear Information System (INIS)

Nagrale, Dhanesh B.; Bera, Subrata; Deo, Anuj Kumar; Paul, U.K.; Prasad, M.; Gaikwad, A.J.

2015-01-01

Nuclear power plants are designed with inherent engineering safety systems and associated operational procedures that provide an in-depth defence against accidents. Radionuclides such as Iodine, Cesium, Tellurium, Barium, Strontium, Rubidium, Molybdenum and many others may get released during a severe accident. Among these, Iodine, one of the fission products, behaviour is significant for the analysis of severe accident consequences because iodine is a chemically more active to the potential components released to the environment. During severe accident, Iodine is released and transported in aqueous, organic and inorganic forms. Iodine release from fuel, iodine transport in primary coolant system, containment, and reaction with control rods are some of the important phases in a severe accident scenario. The behaviour of iodine is governed by aerosol physics, depletion mechanisms gravitational settling, diffusiophoresis and thermophoresis. The presence of gaseous organic compounds and oxidizing compounds on iodine, reactions of aerosol iodine with boron and formation of cesium iodide which results in more volatile iodine release in containment play significant roles. Water radiolysis products due to presence of dissolved impurities, chloride ions, organic impurities should be considered while calculating iodine release. Containment filtered venting system (CFVS) consists of venturi scrubber and a scrubber tank which is dosed with NaOH and NaS_2O_3 in water where iodine will react with the chemicals and convert into NaI and Na_2SO_4. This paper elaborates the issues with respect to interaction of radionuclides and its consideration in modeling of severe accident. (author)

THE EFFECT OF DIFFERENT EXPOSURE CONDITIONS ON THE CHARACTERISTICS OF THE MINERAL MATRICES STABILIZING HAZARDOUS WASTE

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Anna Król

2016-05-01

Full Text Available Mineral binders are more and more often used in the difficult process of disposal of inorganic hazardous waste containing heavy metals. Composites solidifying hazardous waste are deposited in the environment, which exposes them to the interaction of many variable factors. The paper presents the effect of different exposure conditions on physical and mechanical properties of concrete stabilizing galvanic sewage sludge (GO. The effect of the cyclic freezing and thawing, carbon dioxide (carbonation and high temperatures (200 °C, 400 °C, 600 °C on the properties of stabilizing matrices has been described. The results, in most cases, show a loss of durability of composites solidifying sewage sludge (GO by the influence of external conditions.

Experiments to evaluate behavior of containment piping bellows under severe accident conditions

International Nuclear Information System (INIS)

Lambert, L.D.; Parks, M.B.

1993-01-01

Bellows are an integral part of the containment pressure boundary in nuclear power plants. They are used at piping penetrations to allow relative movement between piping and the containment wall. In a severe accident they may be subjected to high pressure and temperature, and a combination of axial and lateral deflections. A test program to determine the leak-tight capacity of containment penetration bellows is being conducted at Sandia National Laboratories, Albuquerque, New Mexico. Several different bellows geometries, representative of actual containment bellows, are being subjected to extreme deflections along with pressure and temperature loads. The bellows geometries and loading conditions are described along with the testing apparatus and procedures. A total of thirteen tests have been conducted. The tests showed that withstanding relatively large bellows are capable of deformations, up to, or near, the point of full compression before developing leakage. The test data is presented and discussed

Response of TLD badge for the estimation of exposure conditions in diagnostic x-ray departments - use of lead aprons

International Nuclear Information System (INIS)

Pradhan, A.S.; Chatterjee, S.; Bakshi, A.K.

2002-01-01

The present study was undertaken to ascertain the conditions of exposure of the TLD badge and to evaluate the inaccuracy involved in the estimation of dose received by the worker using an averaged lead apron transmission factor for the use of the badge above lead apron

Degradation of the pharmaceuticals diclofenac and sulfamethoxazole and their transformation products under controlled environmental conditions

International Nuclear Information System (INIS)

Poirier-Larabie, S.; Segura, P.A.; Gagnon, C.

2016-01-01

Contamination of the aquatic environment by pharmaceuticals via urban effluents is well known. Several classes of drugs have been identified in waterways surrounding these effluents in the last 15 years. To better understand the fate of pharmaceuticals in ecosystems, degradation processes need to be investigated and transformation products must be identified. Thus, this study presents the first comparative study between three different natural environmental conditions: photolysis and biodegradation in aerobic and anaerobic conditions both in the dark of diclofenac and sulfamethoxazole, two common drugs present in significant amounts in impacted surface waters. Results indicated that degradation kinetics differed depending on the process and the type of drug and the observed transformation products also differed among these exposure conditions. Diclofenac was nearly degraded by photolysis after 4 days, while its concentration only decreased by 42% after 57 days of exposure to bacteria in aerobic media and barely 1% in anaerobic media. For sulfamethoxazole, 84% of the initial concentration was still present after 11 days of exposure to light, while biodegradation decreased its concentration by 33% after 58 days of exposure under aerobic conditions and 5% after 70 days of anaerobic exposure. In addition, several transformation products were observed and persisted over time while others degraded in turn. For diclofenac, chlorine atoms were lost primarily in the photolysis, while a redox reaction was promoted by biodegradation under aerobic conditions. For sulfamethoxazole, isomerization was favored by photolysis while a redox reaction was also favored by the biodegradation under aerobic conditions. To summarize this study points out the occurrence of different transformation products under variable degradation conditions and demonstrates that specific functional groups are involved in the tested natural attenuation processes. Given the complexity of environmental

Degradation of the pharmaceuticals diclofenac and sulfamethoxazole and their transformation products under controlled environmental conditions

Energy Technology Data Exchange (ETDEWEB)

Poirier-Larabie, S. [Aquatic Contaminants Research Division, Science and Water Technology Directorate, Environment Canada, Montréal, Québec H2Y 2E7 (Canada); Segura, P.A. [Department of Chemistry, Université de Sherbrooke, Sherbrooke, Québec J1K 2R1 (Canada); Gagnon, C., E-mail: christian.gagnon@canada.ca [Aquatic Contaminants Research Division, Science and Water Technology Directorate, Environment Canada, Montréal, Québec H2Y 2E7 (Canada)

2016-07-01

Contamination of the aquatic environment by pharmaceuticals via urban effluents is well known. Several classes of drugs have been identified in waterways surrounding these effluents in the last 15 years. To better understand the fate of pharmaceuticals in ecosystems, degradation processes need to be investigated and transformation products must be identified. Thus, this study presents the first comparative study between three different natural environmental conditions: photolysis and biodegradation in aerobic and anaerobic conditions both in the dark of diclofenac and sulfamethoxazole, two common drugs present in significant amounts in impacted surface waters. Results indicated that degradation kinetics differed depending on the process and the type of drug and the observed transformation products also differed among these exposure conditions. Diclofenac was nearly degraded by photolysis after 4 days, while its concentration only decreased by 42% after 57 days of exposure to bacteria in aerobic media and barely 1% in anaerobic media. For sulfamethoxazole, 84% of the initial concentration was still present after 11 days of exposure to light, while biodegradation decreased its concentration by 33% after 58 days of exposure under aerobic conditions and 5% after 70 days of anaerobic exposure. In addition, several transformation products were observed and persisted over time while others degraded in turn. For diclofenac, chlorine atoms were lost primarily in the photolysis, while a redox reaction was promoted by biodegradation under aerobic conditions. For sulfamethoxazole, isomerization was favored by photolysis while a redox reaction was also favored by the biodegradation under aerobic conditions. To summarize this study points out the occurrence of different transformation products under variable degradation conditions and demonstrates that specific functional groups are involved in the tested natural attenuation processes. Given the complexity of environmental

Clinical, cardiopulmonary and haemocytological effects of xylazine in goats after acute exposure to different environmental temperature and humidity conditions

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E.G.M. Mogoa

2000-07-01

Full Text Available This study was carried out to assess the influence of xylazine administration on clinical, cardiopulmonary and haemocytological variables after acute exposure to different environmental conditions. Xylazine hydrochloride was administered intravenously at 0.1 mg/kg body mass to 6 clinically healthy, castrated male goats. All animals were exposed for 60 min to 3 sets of climatic conditions: 14 °C, 33% relative humidity; 24 °C, 55% RH, and 34 °C, 65% RH. The variables that were measured for a period of 60 min after xylazine administration were sedation, analgesia, salivation, urination, ventilation rate, heart-rate, mean arterial blood pressure, oesophageal temperature, haematocrit, mean corpuscular volume and mean corpuscular haemoglobin concentration. Xylazine induced sedation, analgesia, salivation and urination independently of the 3 environmental conditions. Environment had no influence on the onset, duration and recovery from sedation. In the 14 °C environment, xylazine resulted in a significant decrease in ventilation and heart-rate from baseline values. Significant changes in mean arterial blood pressure, haemoglobin concentration, mean corpuscular volume, haematocrit and red cell count were observed in the 3 environments. Total plasma protein was significantly altered at 24 °C and 34 °C. Acute exposure of goats to different environmental conditions had no significant influence on the clinical, cardiopulmonary and haemocytological variables. Physiological changes induced by xylazine were therefore independent of the environment.

Some defaults of OILs under emergency conditions in nuclear power plant

International Nuclear Information System (INIS)

Zhang Pengfei; Zhong Chongjun; Gou Quanlu; Wu Deqiang

2005-01-01

Based on the formulae presented in IAEA-TECDOC-955 for operational intervention levels (OILs) under emergency conditions in nuclear power plant (NPP) and by InterRAS1.3 computer code, this paper calculates OIL1 and OIL2 for two kinds of postulated severe accidents (core melt-containment integrity failure or leakage accident and SG integrity severe failure accident) of PWR NPP respectively. OIL1 and OIL2 are used to recommend for public evacuation and taking iodine-blocking agent during the period of plume exposure resulted from the above postulated severe accidents. The effects on OIL1 and OIL2 calculation results of related times (e.g. expected plume exposure time, beginning time of the radioactivity released into the environment), weather conditions (wind speed, height of mixing layer, stability, and rainfall), distance from release source and release patterns (release at low elevation and high elevation) are also discussed. On the basis of the calculation and discussion, this paper presents the relevant recommended defaults of OIL1 and OIL2 for above-mentioned postulated severe accidents, and also points out that OIL1 and OIL2 not only depend on the specific type of accidents, but also on the factors such as whether radioactivity are reduced before being released into the environment, so the defaults shall be presented for different accident types and specific conditions under which radioactivity are how reduced. (authors)

Development of chloride-induced corrosion in pre-cracked RC beams under sustained loading: Effect of load-induced cracks, concrete cover, and exposure conditions

Energy Technology Data Exchange (ETDEWEB)

Yu, Linwen [Université de Toulouse, UPS, INSA, LMDC, Toulouse (France); Université de Sherbrooke, Quebec (Canada); François, Raoul, E-mail: raoul.francois@insa-toulouse.fr [Université de Toulouse, UPS, INSA, LMDC, Toulouse (France); Dang, Vu Hiep [Hanoi Architectural University, Faculty of Civil Engineering, Hanoi (Viet Nam); L' Hostis, Valérie [CEA Saclay, CEA, DEN, DPC, SECR, Laboratoire d' Etude du Comportement des Bétons et des Argiles, Gif-sur-Yvette (France); Gagné, Richard [Université de Sherbrooke, Quebec (Canada)

2015-01-15

This paper deals with corrosion initiation and propagation in pre-cracked reinforced concrete beams under sustained loading during exposure to a chloride environment. Specimen beams that were cast in 2010 were compared to specimens cast in 1984. The only differences between the two sets of beams were the casting direction in relation to tensile reinforcement and the exposure conditions in the salt-fog chamber. The cracking maps, corrosion maps, chloride profiles, and cross-sectional loss of one group of two beams cast in 2010 were studied and their calculated corrosion rates were compared to that of beams cast in 1984 in order to investigate the factors influencing the natural corrosion process. Experimental results show that, after rapid initiation of corrosion at the crack tip, the corrosion process practically halted and the time elapsing before corrosion resumed depended on the exposure conditions and cover depth.

Exposure to high- and low-light conditions in an open-field test of anxiety increases c-Fos expression in specific subdivisions of the rat basolateral amygdaloid complex.

Science.gov (United States)

Hale, Matthew W; Bouwknecht, J Adriaan; Spiga, Francesca; Shekhar, Anantha; Lowry, Christopher A

2006-12-11

Anxiety states and anxiety-related behaviors appear to be regulated by a distributed and highly interconnected system of forebrain structures including the basolateral amygdaloid complex (basolateral amygdala). Despite a wealth of research examining the role of the basolateral amygdala in anxiety-related behaviors and anxiety states, the specific subdivisions of the basolateral amygdala that are involved in responses to anxiogenic stimuli have not been examined. In this study, we investigated the effects of exposure to a novel open-field environment, with either low- or high-levels of illumination, on expression of the protein product of the immediate-early gene c-Fos in subdivisions of the rat basolateral amygdala. The subdivisions studied included the lateral, ventrolateral and ventromedial parts of the lateral amygdaloid nucleus, the anterior, posterior and ventral parts of the basolateral amygdaloid nucleus and the anterior and posterior part of the basomedial amygdaloid nucleus. Small increases in the number of c-Fos-immunoreactive cells were observed in several, but not all, of the subdivisions of the basolateral amygdala studied following exposure of rats to either the high- or low-light conditions, compared to home cage or handled control groups. Open-field exposure in both the high- and low-light conditions resulted in a marked increase in c-Fos expression in the anterior part of the basolateral amygdaloid nucleus compared to either home cage or handled control groups. These findings point toward anatomical and functional heterogeneity within the basolateral amygdaloid complex and an important role of the anterior part of the basolateral amygdaloid nucleus in the neural mechanisms underlying physiological or behavioral responses to this anxiety-related stimulus.

Severe hepatic dysfunction after sevoflurane exposure

International Nuclear Information System (INIS)

Alotaibi, Wadha M.

2008-01-01

Sevoflurane is thought to have a potential for hepatotoxicity. A few cases of hepatotoxicity have been reported since it was introduced in 1999 into clinical practice in Japan. The underlying pathophysiology of hepatotoxicity is non-specific. We report a case of severe hepatic dysfunction after uneventful sevoflurane anesthesia in a child with posterior fossa resection of medulloblastoma. The case of sevoflurane being incriminated is unclear due to various confounding factors that is worthy of discussion. (author)

Effects of Burn Severity and Environmental Conditions on Post-Fire Regeneration in Siberian Larch Forest

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Thuan Chu

2017-03-01

Full Text Available Post-fire forest regeneration is strongly influenced by abiotic and biotic heterogeneity in the pre- and post-fire environments, including fire regimes, species characteristics, landforms, hydrology, regional climate, and soil properties. Assessing these drivers is key to understanding the long-term effects of fire disturbances on forest succession. We evaluated multiple factors influencing patterns of variability in a post-fire boreal Larch (Larix sibirica forest in Siberia. A time-series of remote sensing images was analyzed to estimate post-fire recovery as a response variable across the burned area in 1996. Our results suggested that burn severity and water content were primary controllers of both Larch forest recruitment and green vegetation cover as defined by the forest recovery index (FRI and the fractional vegetation cover (FVC, respectively. We found a high rate of Larch forest recruitment in sites of moderate burn severity, while a more severe burn was the preferable condition for quick occupation by vegetation that included early seral communities of shrubs, grasses, conifers and broadleaf trees. Sites close to water and that received higher solar energy during the summer months showed a higher rate of both recovery types, defined by the FRI and FVC, dependent on burn severity. In addition to these factors, topographic variables and pre-fire condition were important predictors of post-fire forest patterns. These results have direct implications for the post-fire forest management in the Siberian boreal Larch region.

Evaluating the working conditions and exposure to abuse of Filipino home care workers in Israel: characteristics and clinical correlates.

Science.gov (United States)

Ayalon, Liat

2009-02-01

Filipino home care workers provide the majority of around-the-clock personal care to frail individuals in Israel. To date, the working conditions as well as exposure to work-related abuse of Filipino home care workers in Israel have not been evaluated. A survey of 245 Filipino home care workers was conducted to evaluate their working conditions and exposure to abuse as well as their clinical correlates (e.g. burnout as measures by the Maslach Burnout Inventory). This was integrated with findings from interviews with Filipino home care workers, social workers, and family members of care recipients cared by Filipino home care workers. A majority of the workers (88%) reported paying large amounts of money in order to work in the country. Overall, 43% reported being asked to do more than was specified in their job description, 41% reported being verbally abused, and 40% reported not receiving adequate food. Almost half reported work-related injuries. The most consistent predictor of burnout (as measured by the Emotional Exhaustion and Depersonalization scales) was exposure to work-related abuse. Interview data identified system and societal barriers that prevent workers from using the legal system for their protection. The present study calls for further supervision of this caregiving arrangement. Psychoeducational programs directed towards all stakeholders (e.g. social workers, home care workers, care recipients, and family members of care recipients) are needed.

Transesterification of soybean oil with methanol and acetic acid at lower reaction severity under subcritical conditions

International Nuclear Information System (INIS)

Go, Alchris Woo; Sutanto, Sylviana; NguyenThi, Bich Thuyen; Cabatingan, Luis K.; Ismadji, Suryadi; Ju, Yi-Hsu

2014-01-01

Highlights: • (trans)Esterification of oils under subcritical conditions. • Acetic acid as catalyst and co-solvent in biodiesel production. • Influence of reactor hydrodynamic (loading and stirring) on FAME yield. • High methyl ester yield can be obtained at less severe reaction conditions. - Abstract: Soybean oil (56–80 g) was reacted with methanol (40–106 mL) to produce fatty acid methyl ester in the presence of 1–6% acetic acid under subcritical condition at 250 °C. Stirring and loading of the reaction system affected the yield and severity of the process. The presence of acetic acid improved the yield of FAME from 32.1% to 89.5% at a methanol to oil molar ratio of 20 mL/g. Acetic acid was found to act strongly as an acid catalyst and to some extent improved the solubility between oil and methanol. Reaction pressure higher than the supercritical pressure of methanol (7.85 MPa) was not required to achieve high FAME yield (89.5–94.8%) in short time (30–60 min)

Evaluation of Fish Passage Conditions for Juvenile Salmonids Using Sensor Fish at Detroit Dam, Oregon

International Nuclear Information System (INIS)

Duncan, Joanne P.

2010-01-01

Fish passage conditions through two spillways at Detroit Dam on the North Santiam River in Oregon were evaluated by Pacific Northwest National Laboratory for the U.S. Army Corps of Engineers (USACE), Portland District, using Sensor Fish devices. The objective of the study was to describe and compare passage exposure conditions through Spillbay 3 and Spillbay 6 at 1.5- and 3.5-ft gate openings, identifying potential fish injury regions of the routes. The study was performed in July 2009, concurrent with HI-Z balloon-tag studies by Normandeau Associates, Inc. Sensor Fish and live fish were deployed at elevations approximately 3 ft above structure at depths determined using a computational fluid dynamics model. Data collected were analyzed to estimate (1) exposure conditions, particularly exposure to severe collision and shear events by passage route sub-regions; (2) differences in passage conditions between passage routes; and (3) relationships to live-fish injury and mortality data estimates.

Intraperitoneal exposure of whitefish to microcystin-LR induces rapid liver injury followed by regeneration and resilience to subsequent exposures

Energy Technology Data Exchange (ETDEWEB)

Woźny, Maciej, E-mail: maciej.wozny@uwm.edu.pl [Department of Environmental Biotechnology, Faculty of Environmental Sciences, University of Warmia and Mazury in Olsztyn, ul. Słoneczna 45G, 10-709 Olsztyn (Poland); Lewczuk, Bogdan; Ziółkowska, Natalia [Department of Histology and Embryology, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, ul. M. Oczapowskiego 13, 10-713 Olsztyn (Poland); Gomułka, Piotr [Department of Ichthyology, Faculty of Environmental Sciences, University of Warmia and Mazury in Olsztyn, ul. M. Oczapowskiego 5, 10-719 Olsztyn (Poland); Dobosz, Stefan [Department of the Salmonid Research in Rutki, Inland Fisheries Institute in Olsztyn, Rutki, 83-330 Żukowo (Poland); Łakomiak, Alicja; Florczyk, Maciej; Brzuzan, Paweł [Department of Environmental Biotechnology, Faculty of Environmental Sciences, University of Warmia and Mazury in Olsztyn, ul. Słoneczna 45G, 10-709 Olsztyn (Poland)

2016-12-15

To date, there has been no systematic approach comprehensively describing the sequence of pathological changes in fish during prolonged exposure to microcystin-LR (MC-LR). Towards this aim, juvenile whitefish individuals received an intraperitoneal injection with pure MC-LR, and the injection was repeated every week to maintain continuous exposure for 28 days. During the exposure period, growth and condition of the fish were assessed based on biometric measurements. Additionally, selected biochemical markers were analysed in the fishes' blood, and their livers were carefully examined for morphological, ultrastructural, and molecular changes. The higher dose of MC-LR (100 μg·kg{sup −1}) caused severe liver injury at the beginning of the exposure period, whereas the lower dose (10 μg·kg{sup −1}) caused less, probably reversible injury, and its effects began to be observed later in the exposure period. These marked changes were accompanied by substantial MC-LR uptake by the liver. However, starting on the 7th day of exposure, cell debris began to be removed by phagocytes, then by 14th day, proliferation of liver cells had markedly increased, which led to reconstruction of the liver parenchyma at the end of the treatment. Surprisingly, despite weekly-repeated intraperitoneal injections, MC-LR did not accumulate over time of exposure which suggests its limited uptake in the later phase of exposure. In support, mRNA expression of the membrane transport protein oatp1d was decreased at the same time as the regenerative processes were observed. Our study shows that closing of active membrane transport may serve as one defence mechanism against further MC-LR intoxication. - Highlights: • The study presents pathological changes in whitefish during prolonged MC-LR exposure. • After early, severe injury, the damaged liver parenchyma of the fish regenerated. • Endoplasmic reticulum, cytoskeleton, and chromatin were the main targets for MC-LR. • MC-LR did not

Associations of emotional arousal, dissociation and symptom severity with operant conditioning in borderline personality disorder.

Science.gov (United States)

Paret, Christian; Hoesterey, Steffen; Kleindienst, Nikolaus; Schmahl, Christian

2016-10-30

Those with borderline personality disorder (BPD) display altered evaluations regarding reward and punishment compared to others. The processing of rewards is basal for operant conditioning. However, studies addressing operant conditioning in BPD patients are rare. In the current study, an operant conditioning task combining learning acquisition and reversal was used. BPD patients and matched healthy controls (HCs) were exposed to aversive and neutral stimuli to assess the influence of emotion on learning. Picture content, dissociation, aversive tension and symptom severity were rated. Error rates were measured. Results showed no group interactions between aversive versus neutral scenes. The higher emotional arousal, dissociation and tension, the worse the acquisition, but not reversal, scores were for BPD patients. Scores from the Borderline Symptom List were associated with more errors in the reversal, but not the acquisition phase. The results are preliminary evidence for impaired acquisition learning due to increased emotional arousal, dissociation and tension in BPD patients. A failure to process punishment in the reversal phase was associated with symptom severity and may be related to neuropsychological dysfunctioning involving the ventromedial prefrontal cortex. Conclusions are limited due to the correlational study design and the small sample size. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

A microfluidic device with multi-valves system to enable several simultaneous exposure tests on Caenorhabditis elegans

International Nuclear Information System (INIS)

Jung, Jaehoon; Masaru, Takeuchi; Nakajima, Masahiro; Huang, Qiang; Fukuda, Toshio

2014-01-01

In this paper, we report on a microfluidic device with a multi-valve system to conduct several exposure tests on Caenorhabditis elegans (C. elegans) simultaneously. It has pneumatic valves and no-moving-parts (NMP) valves. An NMP valve is incorporated with a chamber and enables the unidirectional movement of C. elegans in the chamber; once worms are loaded into the chamber, they cannot exit, regardless of the flow direction. To demonstrate the ability of the NMP valve to handle worms, we made a microfluidic device with three chambers. Each chamber was used to expose worms to Cd and Cu solutions, and K-medium. A pair of electrodes was installed in the device and the capacitance in-between the electrode was measured. When a C. elegans passed through the electrodes, the capacitance was changed. The capacitance change was proportional to the body volume of the worm, thus the body volume change by the heavy metal exposure was measured in the device. Thirty worms were divided into three groups and exposed to each solution. We confirmed that the different solutions induced differences in the capacitance changes for each group. These results indicate that our device is a viable method for simultaneously analyzing the effect of multiple stimuli on C. elegans. (paper)

Exposure to severe stressors causes long-lasting dysregulation of resting and stress-induced activation of the hypothalamic-pituitary-adrenal axis.

Science.gov (United States)

Belda, Xavier; Rotllant, David; Fuentes, Silvia; Delgado, Raúl; Nadal, Roser; Armario, Antonio

2008-12-01

Exposure to some predominantly emotional (electric shock) and systemic (interleukin-1beta) stressors has been found to induce long-term sensitization of the hypothalamic-pituitary-adrenal (HPA) responsiveness to further superimposed stressors. Since exposure to immobilization on wooden boards (IMO) is a severe stressor and may have interest regarding putative animal models of post-traumatic stress disorders (PTSD), we have characterized long-lasting effects of a single exposure to IMO and other stressors on the HPA response to the same (homotypic) and to novel (heterotypic) stressors and the putative mechanisms involved. A single exposure to IMO caused a long-lasting reduction of peripheral and central responses of the HPA axis, likely to be mediated by some brain areas, such as the lateral septum and the medial amygdala. This desensitization is not explained by changes in negative glucocorticoid feedback, and, surprisingly, it is positively related to the intensity of the stressors. In contrast, the HPA response to heterotypic stressors (novel environments) was enhanced, with maximal sensitization on the day after IMO. Sensitization progressively vanished over the course of 1-2 weeks and was not modulated by IMO-induced corticosterone release. Moreover, it could not be explained by changes in the sensitivity of the HPA axis to fast or intermediate/delayed negative feedback, as evaluated 1 week after exposure to IMO, using shock as the heterotypic stressor. Long-lasting stress-induced behavioral changes reminiscent of enhanced anxiety and HPA sensitization are likely to be parallel but partially independent phenomena, the former being apparently not related to the intensity of stressors.

Severe obesity and comorbid condition impact on the weight-related quality of life of the adolescent patient.

Science.gov (United States)

Zeller, Meg H; Inge, Thomas H; Modi, Avani C; Jenkins, Todd M; Michalsky, Marc P; Helmrath, Michael; Courcoulas, Anita; Harmon, Carroll M; Rofey, Dana; Baughcum, Amy; Austin, Heather; Price, Karin; Xanthakos, Stavra A; Brandt, Mary L; Horlick, Mary; Buncher, Ralph

2015-03-01

To assess links between comorbid health status, severe excess weight, and weight-related quality of life (WRQOL) in adolescents with severe obesity and undergoing weight-loss surgery (WLS) to inform clinical care. Baseline (preoperative) data from Teen Longitudinal Assessment of Bariatric Surgery, a prospective multicenter observational study of 242 adolescents with severe obesity (MedianBMI = 50.5 kg/m(2); Meanage = 17.1; 75.6% female; 71.9% white) undergoing WLS, were used to examine the impact of demographics, body mass index (BMI), presence/absence of 16 comorbid conditions, and a cumulative comorbidity load (CLoad) index on WRQOL scores (Impact of Weight on Quality of Life-Kids). WRQOL was significantly lower than reference samples of healthy weight, overweight, and obese samples. Of 16 comorbid conditions, the most prevalent were dyslipidemia (74.4%), chronic pain (58.3%), and obstructive sleep apnea (56.6%). Male subjects had a greater CLoad (P = .01) and BMI (P = .01), yet less impairment in total WRQOL (P conditions (eg, stress urinary incontinence) also emerged as contributors to lower WRQOL. WRQOL impairment is substantial for adolescents with severe obesity undergoing WLS, with predictors varying by sex. These patient-data highlight targets for education, support, and adjunctive care referrals before WLS. Furthermore, they provide a comprehensive empirical base for understanding heterogeneity in adolescent WRQOL outcomes after WLS, as weight and comorbidity profiles change over time. Copyright © 2015 Elsevier Inc. All rights reserved.

Evolution of the Sensor Fish Device for Measuring Physical Conditions in Severe Hydraulic Environments

Energy Technology Data Exchange (ETDEWEB)

Carlson, Thomas J.; Duncan, Joanne P.

2003-02-28

To assist in deriving biological specifications for design of turbine rehabilitation measures, new ''fish-friendly'' turbines, and spillway designs and operations, scientists at the Pacific Northwest National Laboratory (PNNL) have developed and tested an autonomous multi-sensor device called a Sensor Fish that can acquire pressure and tri-axial linear acceleration data during passage through severe hydraulic conditions. The purpose of the Sensor Fish is to characterize physical conditions fish experience during passage through hydro turbines, spill stilling basins, high-discharge outfalls, and other dam passage routes. The Sensor Fish was developed with the support of the U.S. Department of Energy's Advanced Hydropower Turbine System program. Field tests of the Sensor Fish at Rock Island, McNary, The Dalles, Bonneville, and Wanapum dams on the Columbia River and the Prosser Irrigation District on the Yakima River have shown that the device can withstand the severe environments of turbine, spill, and fish bypass passage and provide useful environmental data that can ultimately aid in the design and operation of new and existing turbines, spill, and dam fish bypass facilities.

Air-breathing behavior and physiological responses to hypoxia and air exposure in the air-breathing loricariid fish, Pterygoplichthys anisitsi.

Science.gov (United States)

da Cruz, André Luis; da Silva, Hugo Ribeiro; Lundstedt, Lícia Maria; Schwantes, Arno Rudi; Moraes, Gilberto; Klein, Wilfried; Fernandes, Marisa Narciso

2013-04-01

Hypoxic water and episodic air exposure are potentially life-threatening conditions that fish in tropical regions can face during the dry season. This study investigated the air-breathing behavior, oxygen consumption, and respiratory responses of the air-breathing (AB) armored catfish Pterygoplichthys anisitsi. The hematological parameters and oxygen-binding characteristics of whole blood and stripped hemoglobin and the intermediate metabolism of selected tissue in normoxia, different hypoxic conditions, and after air exposure were also examined. In normoxia, this species exhibited high activity at night and AB behavior (2-5 AB h(-1)). The exposure to acute severe hypoxia elicited the AB behavior (4 AB h(-1)) during the day. Under progressive hypoxia without access to the water surface, the fish were oxyregulators with a critical O2 tension, calculated as the inspired water O2 pressure, as 47 ± 2 mmHg. At water O2 tensions lower than 40 mmHg, the fish exhibited continuous apnea behavior. The blood exhibited high capacity for transporting O2, having a cathodic hemoglobin component with a high Hb-O2 affinity. Under severe hypoxia, the fish used anaerobic metabolism to maintain metabolic rate. Air exposure revealed physiological and biochemical traits similar to those observed under normoxic conditions.

Independent and additive association of prenatal famine exposure and intermediary life conditions with adult mortality between age 18-63 years

NARCIS (Netherlands)

Ekamper, P.; van Poppel, F.W.A.; Stein, A.D.; Lumey, L.H.

2014-01-01

Objectives To quantify the relation between prenatal famine exposure and adult mortality, taking into account mediating effects of intermediary life conditions. Design Historical follow-up study. Setting The Dutch famine (Hunger Winter) of 1944–1945 which occurred towards the end of WWII in occupied

Studies on the role of molybdenum on iodine transport in the RCS in nuclear severe accident conditions

International Nuclear Information System (INIS)

Grégoire, A.-C.; Kalilainen, J.; Cousin, F.; Mutelle, H.; Cantrel, L.; Auvinen, A.; Haste, T.; Sobanska, S.

2015-01-01

Highlights: • In oxidising conditions, Mo reacts with Cs and thus promotes gaseous iodine release. • In reducing conditions, CsI remains the dominant form for released iodine. • The nature of released iodine is well reproduced by the ASTEC code. - Abstract: The effect of molybdenum on iodine transport in the reactor coolant system (RCS) under PWR severe accident conditions was investigated in the framework of the EU SARNET project. Experiments were conducted at the VTT-Institute and at IRSN and simulations of the experimental results were performed with the ASTEC severe accident simulation code. As molybdenum affects caesium chemistry by formation of molybdates, it may have a significant impact on iodine transport in the RCS. Experimentally it has been shown that the formation of gaseous iodine is promoted in oxidising conditions, as caesium can be completely consumed to form caesium polymolybdates and is thus not available for reacting with gaseous iodine and leading to CsI aerosols. In reducing conditions, CsI remains the dominant form of iodine, as the amount of oxygen is not sufficient to allow formation of quantitative caesium polymolybdates. An I–Mo–Cs model has been developed and it reproduces well the experimental trends on iodine transport

Widespread exposure to lead affects the body condition of free-living whooper swans Cygnus cygnus wintering in Britain

International Nuclear Information System (INIS)

Newth, J.L.; Rees, E.C.; Cromie, R.L.; McDonald, R.A.; Bearhop, S.; Pain, D.J.; Norton, G.J.; Deacon, C.; Hilton, G.M.

2016-01-01

Lead poisoning, through the ingestion of spent lead gunshot, is an established cause of morbidity and mortality in waterbirds globally, but the thresholds at which blood levels begin to affect the physiology of birds in the wild are less well known. Here we determine the prevalence of lead exposure in whooper swans and, for the first time, identify the level of blood lead associated with initial reductions in body condition. Blood lead elevated above background levels (i.e. >20 μg dL"−"1) was found in 41.7% (125/300) of swans tested. Blood lead was significantly negatively associated with winter body condition when levels were ≥44 μg dL"−"1 (27/260 = 10%). Our findings indicating that sub-lethal impacts of lead on body condition occur at the lower end of previously established clinical thresholds and that a relatively high proportion of individuals in this population may be affected, reaffirm the importance of reducing contamination of the environment with lead shot. - Highlights: • Elevated blood lead levels of >20 μg dL"−"1 were found in 41.7% of whooper swans. • Blood lead levels of ≥44 μg dL"−"1 were negatively associated with body condition. • Clinical effects were at lower levels than previously described for Anseriformes. • Reduction of lead shot in the environment would reduce the risk of lead exposure. - Blood lead was significantly negatively associated with the body condition of free-living whooper swans in winter when levels were ≥44 μg dL"−"1 (27/260 = 10% of birds were above this threshold).

Human health risk assessment related to cyanotoxins exposure.

Science.gov (United States)

Funari, Enzo; Testai, Emanuela

2008-01-01

This review focuses on the risk assessment associated with human exposure to cyanotoxins, secondary metabolites of an ubiquitous group of photosynthetic procariota. Cyanobacteria occur especially in eutrophic inland and coastal surface waters, where under favorable conditions they attain high densities and may form blooms and scums. Cyanotoxins can be grouped according to their biological effects into hepatotoxins, neurotoxins, cytotoxins, and toxins with irritating potential, also acting on the gastrointestinal system. The chemical and toxicological properties of the main cyanotoxins, relevant for the evaluation of possible risks for human health, are presented. Humans may be exposed to cyanotoxins via several routes, with the oral one being by far the most important, occurring by ingesting contaminated drinking water, food, some dietary supplements, or water during recreational activities. Acute and short-term toxic effects have been associated in humans with exposure to high levels of cyanotoxins in drinking and bathing waters. However, the chronic exposure to low cyanotoxin levels remains a critical issue. This article identifies the actual risky exposure scenarios, provides toxicologically derived reference values, and discusses open issues and research needs.

Modelling and simulation of concrete leaching under outdoor exposure conditions

International Nuclear Information System (INIS)

Schiopu, Nicoleta; Tiruta-Barna, Ligia; Jayr, Emmanuel; Mehu, Jacques; Moszkowicz, Pierre

2009-01-01

Recently, a demand regarding the assessment of release of dangerous substances from construction products was raised by European Commission which has issued the Mandate M/366 addressed to CEN. This action is in relation with the Essential Requirement No. 3 'Hygiene, Health and Environment' of the Construction Products Directive (89/106/EC). The potential hazard for environment and health may arise in different life cycle stages of a construction product. During the service life stage, the release of substances due to contact with the rain water is the main potential hazard source, as a consequence of the leaching phenomenon. The objective of this paper is to present the development of a coupled chemical-transport model for the case of a concrete based construction product, i.e. concrete paving slabs, exposed to rain water under outdoor exposure conditions. The development of the model is based on an iterative process of comparing the experimental results with the simulated results up to an acceptable fit. The experiments were conducted at laboratory scale (equilibrium and dynamic leaching tests) and field scale. The product was exposed for one year in two types of leaching scenarios under outdoor conditions, 'runoff' and 'stagnation', and the element release was monitored. The model was calibrated using the experimental data obtained at laboratory scale and validated against measured field data, by taking into account the specific rain water balance and the atmospheric CO 2 uptake as input parameters. The numerical tool used in order to model and simulate the leaching behaviour was PHREEQC, coupled with the Lawrence Livermore National Laboratory (LLNL) thermodynamic data base. The simulation results are satisfying and the paper demonstrates the feasibility of the modelling approach for the leaching behaviour assessment of concrete type construction materials

Earthworm responses to Cd and Cu under fluctuating environmental conditions: a comparison with results from laboratory exposures

International Nuclear Information System (INIS)

Spurgeon, David J.; Svendsen, Claus; Lister, Lindsay J.; Hankard, Peter K.; Kille, Peter

2005-01-01

Laboratory toxicity tests are usually conducted under stable ambient conditions, while exposures in ecosystems occur in a fluctuating climate. To assess how climate influences the toxicity of Cu and Cd for the earthworm Lumbricus rubellus, this study compared effects for life-cycle parameters (survival, reproduction), cellular status (lysosomal membrane stability), gene expression (transcript of the metal binding protein metallothionein-2) and tissue metal concentration measured under outdoor conditions, with the same responses under constant conditions as measured by Spurgeon et al. [Spurgeon, D.J., Svendsen, C., Weeks, J.M., Hankard, P.K., Stubberud, H.E., Kammenga, J.E., 2003. Quantifying copper and cadmium impacts on intrinsic rate of population increase in the terrestrial oligochaete Lumbricus rubellus. Environmental Toxicology and Chemistry 22, 1465-1472]. Both metals were found to significantly influence earthworm reproduction, compromise lysosomal membrane stability and induce MT-2 gene expression in the outdoor system. Comparison with physiological and life-cycle responses in the laboratory indicated similar response patterns and effect concentrations for Cu. For Cd, lysosomal membrane stability and MT-2expression showed comparable responses in both exposures. Juvenile production rate, however, gave different dose response relationships, with the EC- 50 in the outdoor test approximately half that in the laboratory test. A difference in Cd accumulation was also seen. Overall, however, the comparison indicated only a marginal effect of environmental fluctuations typical for northern temperate Europe on earthworm sensitivity to the two metals. - Comparative analysis of life-cycle, physiological and molecular responses to Cu and Cd indicate similar responses under static and fluctuating climate regimes

Modelling of the mammographic exposure conditions for radiological detriment study in the Valencian Breast Cancer Screening Programme

International Nuclear Information System (INIS)

Ferrer, S.; Ramos, M.; Villaescusa, J. I.; Verdu, G.; Salas, M. D.; Cuevas, M. D.

2005-01-01

Breast screening programmes are the best weapon to fight against breast cancer. Nevertheless, despite the benefits, this practice supposes a radiological risk that cannot be forgotten. In order to calculate breast glandular doses, different MCNP-4C2 models have been developed, simulating the exposure conditions. Radiological detriments have been transported from the population under study in the UNSCEAR 2000 to the Valencian Community, obtaining the detection-induced cancer ratio (DICR) for this population. (authors)

[Accumulative effects and long-term persistence of subliminal mere exposure].

Science.gov (United States)

Kawakami, Naoaki; Yoshida, Fujio

2011-10-01

We examined the accumulative effects and long-term persistence of subliminal mere exposure. An accumulative exposure condition (100 exposures distributed over five days) and a massed exposure condition (100 exposures in one day) were used in a Go/No-go Association Task (GNAT), with assessments of likability from Time 1 (just after) to Time 6 (after three months). First, a single stimulus was shown subliminally for a total of 100 times. The results indicated that mere exposure effects occurred equally often at Time 1. However, after Time 2, likability gradually decreased under the massed exposure condition, while it did not decrease under the accumulative exposure condition until Time 6. Second, in order to investigate the effect of multiple exposure, five stimuli belonging to a common category were shown 20 times each, for a total of 100 times. An ANOVA suggested that massed exposure had an instantaneous effect on likability, whereas accumulative exposure had a long-term persistence effect. Also, multiple exposures strengthened the mere exposure effect.

Epidemic gasoline exposures following Hurricane Sandy.

Science.gov (United States)

Kim, Hong K; Takematsu, Mai; Biary, Rana; Williams, Nicholas; Hoffman, Robert S; Smith, Silas W

2013-12-01

Major adverse climatic events (MACEs) in heavily-populated areas can inflict severe damage to infrastructure, disrupting essential municipal and commercial services. Compromised health care delivery systems and limited utilities such as electricity, heating, potable water, sanitation, and housing, place populations in disaster areas at risk of toxic exposures. Hurricane Sandy made landfall on October 29, 2012 and caused severe infrastructure damage in heavily-populated areas. The prolonged electrical outage and damage to oil refineries caused a gasoline shortage and rationing unseen in the USA since the 1970s. This study explored gasoline exposures and clinical outcomes in the aftermath of Hurricane Sandy. Prospectively collected, regional poison control center (PCC) data regarding gasoline exposure cases from October 29, 2012 (hurricane landfall) through November 28, 2012 were reviewed and compared to the previous four years. The trends of gasoline exposures, exposure type, severity of clinical outcome, and hospital referral rates were assessed. Two-hundred and eighty-three gasoline exposures were identified, representing an 18 to 283-fold increase over the previous four years. The leading exposure route was siphoning (53.4%). Men comprised 83.0% of exposures; 91.9% were older than 20 years of age. Of 273 home-based calls, 88.7% were managed on site. Asymptomatic exposures occurred in 61.5% of the cases. However, minor and moderate toxic effects occurred in 12.4% and 3.5% of cases, respectively. Gastrointestinal (24.4%) and pulmonary (8.4%) symptoms predominated. No major outcomes or deaths were reported. Hurricane Sandy significantly increased gasoline exposures. While the majority of exposures were managed at home with minimum clinical toxicity, some patients experienced more severe symptoms. Disaster plans should incorporate public health messaging and regional PCCs for public health promotion and toxicological surveillance.

Under which conditions does T1 difficulty affect T2 performance in the attentional blink?

DEFF Research Database (Denmark)

Nielsen, Simon; Petersen, Anders; Andersen, Tobias Søren

2009-01-01

When two visual targets (T1 & T2) are presented in rapid succession, performance of T2 suffers up to 900 ms. One theory of this attentional blink (Raymond, Shapiro, & Arnell, 1992) propose that T1 and T2 compete for limited processing resources (Chun & Potter, 1995), and predict that prolonging...... processing time for T1 by increasing its perceptual difficulty will induce a larger blink. Several studies have tested this prediction without reaching a consistent answer. McLaughlin, Shore, & Klein (2001) found no effect of the exposure duration of T1 on the attentional blink. Christmann & Leuthold (2004...... duration. In the hard condition, T1 exposure duration was 10 ms while T1 contrast was adjusted individually to reach 50% correct T1 identification. In the long duration condition, T1 exposure duration was increased to reach approximately 90% correct T1 identification. In the high contrast condition, T1...

Cumulative effects of heat exposure and storage conditions of Oxytocin-in-Uniject in rural Ghana: implications for scale up.

Science.gov (United States)

Mullany, Luke C; Newton, Sam; Afari-Asiedu, Samuel; Adiibokah, Edward; Agyemang, Charlotte T; Cofie, Patience; Brooke, Steve; Owusu-Agyei, Seth; Stanton, Cynthia K

2014-08-01

Postpartum hemorrhage can be reduced substantially in home deliveries attended by community-based workers by using Oxytocin-in-Uniject (OIU) devices affixed with temperature-time indicators. We characterized the distribution of time to discard of these devices when stored under normal field conditions in Ghana. Two drug storage simulation studies were conducted in rural Ghana in 2011 and 2012. Devices were transported under refrigeration from manufacture (Argentina) to storage at the study site. Twenty-three field workers each stored at home (unrefrigerated) 25 OIU devices and monitored them daily to record: (1) time to transition from usable to unusable, and (2) continuous digital ambient temperature to determine heat exposure over the simulation period. Time to discard was estimated and compared with mean kinetic temperature exposure of the devices during the shipment and storage phases and with characteristics of the storage locations using Weibull regression models. We used the time to discard distributions in a Monte Carlo simulation to estimate wastage rates in a hypothetical program setting. Time for shipment and transfer to long-term refrigerated storage and mean kinetic temperature during the shipment phase was 8.6 days/10.3°C and 13.4 days/12.1°C, for the first and second simulation studies, respectively. Median (range) time to discard when stored under field conditions (unrefrigerated) was 43 (6 to 59) days and 33 (14 to 50) days, respectively. Mean time to discard was 10.0 days shorter in the second simulation, during which mean kinetic temperature exposure was 3.9°C higher. Simulating a monthly distribution system and assuming typical usage, predicted wastage of product was less than 10%. The time to discard of devices was highly sensitive to small changes in temperature exposure. Under field conditions typical in rural Ghana, OIU packages will have a half-life of approximately 30 to 40 days based on the temperature monitor used during the study

Exposure to histone deacetylase inhibitors during Pavlovian conditioning enhances subsequent cue-induced reinstatement of operant behavior.

Science.gov (United States)

Ploense, Kyle L; Kerstetter, Kerry A; Wade, Matthew A; Woodward, Nicholas C; Maliniak, Dan; Reyes, Michael; Uchizono, Russell S; Bredy, Timothy W; Kippin, Tod E

2013-06-01

Histone deacetylase inhibitors (HDACIs) strengthen memory following fear conditioning and cocaine-induced conditioned place preference. Here, we examined the effects of two nonspecific HDACIs, valproic acid (VPA) and sodium butyrate (NaB), on appetitive learning measured by conditioned stimulus (CS)-induced reinstatement of operant responding. Rats were trained to lever press for food reinforcement and then injected with VPA (50-200 mg/kg, i.p.), NaB (250-1000 mg/kg, i.p.), or saline vehicle (1.0 ml/kg), 2 h before receiving pairings of noncontingent presentation of food pellets preceded by a tone+light cue CS. Rats next underwent extinction of operant responding followed by response-contingent re-exposure to the CS. Rats receiving VPA (100 mg/kg) or NaB (1000 mg/kg) before conditioning displayed significantly higher cue-induced reinstatement than did saline controls. Rats that received either vehicle or VPA (100 mg/kg) before a conditioning session with a randomized relation between presentation of food pellets and the CS failed to show subsequent cue-induced reinstatement with no difference between the two groups. These findings indicate that, under certain contexts, HDACIs strengthen memory formation by specifically increasing the associative strength of the CS, not through an increasing motivation to seek reinforcement. © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Vaporization of low-volatile fission products under severe CANDU reactor accident conditions

International Nuclear Information System (INIS)

Lewis, B.J.; Corse, B.J.; Thompson, W.T.; Kaye, M.H.; Iglesias, F.C.; Elder, P.; Dickson, R.; Liu, Z.

1997-01-01

An analytical model has been developed to describe the release behaviour of low-volatile fission products from uranium dioxide fuel under severe reactor accident conditions. The effect of the oxygen potential on the chemical form and volatility of fission products is determined by Gibbs-energy minimization. The release kinetics are calculated according to the rate-controlling step of diffusional transport in the fuel matrix or fission product vaporization from the fuel surface. The effect of fuel volatilization (i.e., matrix stripping) on the release behaviour is also considered. The model has been compared to data from an out-of-pile annealing experiment performed in steam at the Chalk River Laboratories. (author)

Fetal and infant exposure to severe Chinese famine increases the risk of adult dyslipidemia: Results from the China health and retirement longitudinal study.

Science.gov (United States)

Wang, Zhenghe; Li, Changwei; Yang, Zhongping; Ma, Jun; Zou, Zhiyong

2017-06-14

To explore the associations between the Chinese famine exposure in early life and the dyslipidemia in adulthood. We selected 2752 participants from the baseline survey of China Health and Retirement Longitudinal Study (CHARLS) 2011-2012 to evaluate the associations of early life the Chinese famine exposure with risk of dyslipidemia in adulthood. Dyslipidemia was defined as TC (Total Cholesterol): HDL-C (High-Density Lipoprotein Cholesterol) ratio ≥ 5.0 or use cholesterol lowering drugs. Famine exposure cohorts were categorized by birthdates of participants. Binary logistics regression model was used to examine the associations of early-life famine exposure with the risk of dyslipidemia. The dyslipidemia prevalence of the non-exposed cohort, fetal stage-, infant stage-, and preschool stage-exposed cohorts in adulthood was 15.7%, 23.1%, 22.0%, and 18.6%, respectively. Early-life exposure to the Chinese famine significantly increased LDL cholesterol concentrations in adulthood after adjusted for age. The risks of dyslipidemia in fetal (OR = 1.58; 95% CI: 1.23-2.03; P dyslipidemia in female adults. However, the similar association was not observed for male adults. Early-life exposure to severe Chinese famine could link with the higher dyslipidemia risk in female adulthood, but not in male adulthood. This gender-specific effect might be associated with the hypothesis that parents in China prefer boys to girls traditionally or survivors' bias.

Sequential and simultaneous thermal and particle exposure of tungsten

International Nuclear Information System (INIS)

Steudel, I; Huber, A; Kreter, A; Linke, J; Sergienko, G; Unterberg, B; Wirtz, M

2016-01-01

The broad array of expected loading conditions in a fusion reactor such as ITER necessitates high requirements on the plasma facing materials (PFMs). Tungsten, the PFM for the divertor region, the most affected part of the in-vessel components, must thus sustain severe, distinct exposure conditions. Accordingly, comprehensive experiments investigating sequential and simultaneous thermal and particle loads were performed on double forged pure tungsten, not only to investigate whether the thermal and particle loads cause damage but also if the sequence of exposure maintains an influence. The exposed specimens showed various kinds of damage such as roughening, blistering, and cracking at a base temperature where tungsten could be ductile enough to compensate the induced stresses exclusively by plastic deformation (Pintsuk et al 2011 J. Nucl. Mater. 417 481–6). It was found out that hydrogen has an adverse effect on the material performance and the loading sequence on the surface modification. (paper)

REQUIREMENTS TO THE LIMITATION OF POPULATION EXPO-SURE FROM THE NATIRAL IONIZING IRRADIATION SOURCES IN INDUSTRIAL CONDITIONS

Directory of Open Access Journals (Sweden)

I. P. Stamat

2010-01-01

Full Text Available The paper presents conceptually new requirements to the limitation of population exposure from the natural ionizing irradiation sources in industrial conditions, introduced into Basic Sanitary Rules of Radiation Safety (OSPORB-99/2010. It is shown that, first of all, introduction of these requirements is aimed at the resolution of variety of previously existing serious contradictions in organization of radiation safety control and supervision for the impact of natural ionizing irradiation sources in industry.

The impact of prodromal symptoms on dose monitoring for whole body radiation exposure

International Nuclear Information System (INIS)

Hartmann, A.; Bojar, H.; Zamboglou, N.; Pape, H.; Schnabel, T.; Schmitt, G.

1994-01-01

The triage of victims after radiation injury is complicated by missing dose values and the fact that most tissues react after a latency period. We evaluated 63 patients undergoing total body irradiation as conditioning regime before bone marrow transplantation in order to find a relation between prodromal symptoms and dose. Emesis after radiation exposure hints to doses greater than 1.5 Gy. A rise of body temperature above 37 C up to five hours after exposure is related to doses exceeding 2.5 Gy, while an acute onset of diarrhoea is an indicator of a severe accident with more than 9 Gy. Besides blood counts and chromosome analyses a careful evaluation of prodromal symptoms can help to classify the severity of radiation accidents. (orig./MG) [de

Hydrogen-control systems for severe LWR accident conditions - a state-of-technology report

International Nuclear Information System (INIS)

Hilliard, R.K.; Postma, A.K.; Jeppson, D.W.

1983-03-01

This report reviews the current state of technology regarding hydrogen safety issues in light water reactor plants. Topics considered in this report relate to control systems and include combustion prevention, controlled combustion, minimization of combustion effects, combination of control concepts, and post-accident disposal. A companion report addresses hydrogen generation, distribution, and combustion. The objectives of the study were to identify the key safety issues related to hydrogen produced under severe accident conditions, to describe the state of technology for each issue, and to point out ongoing programs aimed at resolving the open issues

Cadmium toxicity studies under long term-low level exposure (LLE) conditions. I

International Nuclear Information System (INIS)

Sabbioni, E.; Marafante, E.; Amantini, L.; Ubertalli, L.; Pietra, R.

1978-01-01

A long term-low level exposure (LLE) experiment was conducted on rats to determine the metabolic patterns for realistic dietary levels of cadmium. Male rats fed with 61 ppb of cadmium ad libitum, 50 labelled with 109 Cd radiotracer as cadmium chloride via drinking mineral water and 11 unlabelled via food for 2 years. The diet was characterized in its metal content by neutron activation analysis to obtain the total dietary intake of different elements. The kidney was found to be the tissue with the major concentration of cadmium which accumulated continuously during the experiment. The variation of the accumulation pattern of Cd concentration in the liver and intestine indicated an initial rapid increase of Cd during the first 100 days. After this period an apparent equilibrium was attained in both these tissues until the end of the study. The intracellular distribution of cadmium in kidneys, liver, intestine and pancreas were similar, the cytosol fractions containing about 80% of the cellular cadmium. Dialysis experiments indicated that significant amounts of cadmium were able to be associated with cellular organelles, the mitochondria representing the most important organelle capable of binding cadmium. The cytoplasmatic Cd-profiles obtained at various stages of the experiment showed that the metal was only bound to a low-molecular-weight component, cadmium-binding protein (CdBP), which represents the specific cellular-binding component for cadmium under the long term-low level exposure (LLE) conditions. No significant variations in the concentrations of the elements in different organs were observed in animals supplemented with 109 Cd in respect to 109 Cd untreated controls. (Auth.)

Simulation of experiment on aerosol behaviour at severe accident conditions in the LACE experimental facility with the ASTEC CPA code

International Nuclear Information System (INIS)

Kljenak, I.; Mavko, B.

2007-01-01

The experiment LACE LA4 on thermal-hydraulics and aerosol behavior in a nuclear power plant containment, which was performed in the LACE experimental facility, was simulated with the ASTEC CPA module of the severe accident computer code ASTEC V1.2. The specific purpose of the work was to assess the capability of the module (code) to simulate thermal-hydraulic conditions and aerosol behavior in the containment of a light-water-reactor nuclear power plant at severe accident conditions. The test was simulated with boundary conditions, described in the experiment report. Results of thermal-hydraulic conditions in the test vessel, as well as dry aerosol concentrations in the test vessel atmosphere, are compared to experimental results and analyzed. (author)

Iodine/steel reactions under severe accident conditions in LWR's

International Nuclear Information System (INIS)

Funke, F.; Greger, G-U.; Hellman, S.; Bleier, A.; Morell, W.

1994-01-01

Due to large surface areas, the reaction of volatile, molecular iodine (I 2 ) with steel surfaces in the containment may play an important role in predicting the source term to the environment. Both wall retention of iodine and conversion of volatile into non-volatile iodine compounds at steel surfaces have to be considered. Two types of laboratory experiments were carried out at Siemens/KWU in order to investigate the reaction of I 2 at steel surfaces representative for German power plants. 1) For steel coupons submerged in an I 2 solution at T = 50 deg C, 90 deg C or 140 deg C the reaction rate of the I 2 /I - conversion was determined. No iodine loading was observed on the steel in the aqueous phase tests. I 2 reacts with the steel components (Fe, Cr or Ni) to form metal iodides on the surface which are all immediately dissolved in water under dissociation into the metal and the iodide ions. From these experiments, the I 2 /I - conversion rate constants over the temperature range 50 deg C - 140 deg C as well as the activation energy were determined. The measured data are suitable to be included in severe accident iodine codes such as IMPAIR. 2) Steel tubes were exposed to a steam/I 2 flow under dry air at T=120 deg C and steam-condensing conditions at T= 120 deg C and 160 deg C. In dry air I 2 was retained on the steel surface and a deposition rate constant was measured. Under steam-condensing conditions there is an effective conversion of volatile I 2 to non-volatile I - which is subsequently washed off from the steel surface. The I 2 /I - conversion rate constants suitable for modelling this process were determined. No temperature dependency was found in the range 120 deg C - 160 deg C. (author). 4 refs., 2 tabs., 7 figs

Exposure scenarios for workers

NARCIS (Netherlands)

Marquart, H.; Northage, C.; Money, C.

2007-01-01

The new European chemicals legislation REACH (Registration, Evaluation, Authorisation and restriction of Chemicals) requires the development of Exposure Scenarios describing the conditions and risk management measures needed for the safe use of chemicals. Such Exposure Scenarios should integrate

Under which conditions does T1 difficulty affect T2 performance in the attentional blink?

DEFF Research Database (Denmark)

Nielsen, Simon; Petersen, Anders; Andersen, Tobias

When two visual targets (T1 & T2) are presented in rapid succession, performance of T2 suffers up to 900 ms. One theory of this attentional blink (Raymond, Shapiro, & Arnell, 1992) propose that T1 and T2 compete for limited processing resources (Chun & Potter, 1995), and predict that prolonging...... processing time for T1 by increasing its perceptual difficulty will induce a larger blink. Several studies have tested this prediction without reaching a consistent answer. McLaughlin, Shore, & Klein (2001) found no effect of the exposure duration of T1 on the attentional blink. Christmann & Leuthold (2004...... duration. In the hard condition, T1 exposure duration was 10 ms while T1 contrast was adjusted individually to reach 50% correct T1 identification. In the long duration condition, T1 exposure duration was increased to reach approximately 90% correct T1 identification. In the high contrast condition, T1...

Personal monitoring of 218Po and 214Po radionuclide deposition onto individuals under normal environmental exposure conditions

International Nuclear Information System (INIS)

Eatough, J.P.; Worley, A.; Moss, G.R.

1999-01-01

Personal dosemeters have been utilized to monitor the deposition of the radon decay products 218 Po and 214 Po onto individuals under normal environmental exposure conditions. Each detector consists of TASTRAK alpha-sensitive plastic incorporated into an ordinary working wristwatch. Subsequent analysis provides energy discrimination of the detected alpha-particle decays, and allows events from the individual radon decay products 218 Po and 214 Po, attached to the detector surface, to be uniquely identified. Assuming similar deposition onto skin and detector surfaces, the activity per unit area of deposited radionuclides can be determined for exposed skin. Forty-one personal dosemeters were issued to volunteers selected through the hospital medical physics departments at Reading, Northampton, Exeter and Plymouth. Each volunteer was also issued with a personal radon dosemeter to determine their individual radon exposure. The volunteers wore the two dosemeters simultaneously and continuously for a period of around one month. Correlations were observed between the radon exposure of the individual and the activity per unit area of 218 Po and 214 Po on the detector surface. From these correlations it can be estimated that at the UK average radon exposure of 20 Bq m -3 , the number of decays/cm 2 /year on continuously exposed skin surface is between 3500 and 28 000 for 218 Po, and between 7000 and 21 000 for 214 Po. These results can be combined with theoretical modelling of the dose distribution in the skin to yield the alpha-particle radiation dose to any identified target cells. (author)

[Relationships between air conditioning, airborne microorganisms and health].

Science.gov (United States)

Parat, S; Perdrix, A; Baconnier, P

1999-01-01

Concurrently with the increase of air-conditioning, potentially severe or frequent new diseases have emerged, giving rise to social and economical consequences. The first part of this work is a state of the art review of the relationships between air-conditioning, airborne microorganisms and health, through a technical, metrological and medical approach. The second part presents four studies performed in this field. Two of them deal with the relationship between airborne microorganisms and technical features of air-conditioning. Measurements performed on actual sites demonstrated the benefit of using high efficiency filters and low risk components in air-conditioning systems. The third study was aimed to look for a relationship between airborne microorganisms and sick building syndrome symptoms. Statistical analyses of individual data revealed significant associations between airborne bacteria or fungi and symptoms. These results may be the first step in determining a dose-response relationship, in order to define threshold limit values in this field. In the fourth study, the contribution of particle counting in assessing exposure to airborne microorganisms was explored by monitoring simultaneous variations of microbial and particle concentrations. The results showed that associating particle counting may allow to detect microbial variations instantaneously, and therefore improve the assessment of exposure to airborne microorganisms.

Durability study and lifetime prediction of baseline proton exchange membrane fuel cell under severe operating conditions

Energy Technology Data Exchange (ETDEWEB)

Marrony, M.; Quenet, S.; Aslanides, A. [European Institute for Energy Research, Emmy-Noether Strasse 11, 76131 Karlsruhe (Germany); Barrera, R.; Ginocchio, S.; Montelatici, L. [Edison, Via Giorgio La Pira 2, 10028 Trofarello (Italy)

2008-08-01

Comparative studies of mechanical and electrochemical properties of Nafion{sup registered} - and sulfonated polyetheretherketone polymer-type membranes are carried out under severe fuel cell conditions required by industrials, within stationary and cycling electric load profiles. These membranes are proposed to be used in PEM between 70 and 90 C as fluorinated or non-fluorinated baseline membranes, respectively. Thus, though the performance of both membranes remains suitable, Nafion{sup registered} backbone brought better mechanical properties and higher electrochemical stabilities than sulfonated polyetheretherketone backbone. The performance stability and the mechanical strength of the membrane-electrode assembly were shown to be influenced by several intrinsic properties of the membrane (e.g., thermal pre-treatment, thickness) and external conditions (fuel cell operating temperature, relative humidity). Finally, a lifetime prediction for membranes under stationary conditions is proposed depending on the operation temperature. At equivalent thicknesses (i.e. 50 {mu}m), Nafion{sup registered} membranes were estimated able to operate into the 80-90 C range while sulfonated polyetheretherketone would be limited into the 70-80 C range. This approach brings baseline information about the capability of these types of polymer electrolyte membrane under fuel cell critical operations. Finally, it is revealed as a potential tool for the selection of the most promising advanced polymers for the ensuing research phase. (author)

Role of Passive Safety Features in Prevention And Mitigation of Severe Plant Conditions in Indian Advanced Heavy Water Reactor

Energy Technology Data Exchange (ETDEWEB)

Jain, Vikas; Nayak, A.; Dhiman, M.; Kulkarni, P. P.; Vijayan, P. K.; Vaze, K. K. [Bhabha Atomic Research Centre, Mumbai (India)

2013-10-15

Pressing demands of economic competitiveness, the need for large-scale deployment, minimizing the need of human intervention, and experience from the past events and incidents at operating reactors have guided the evolution and innovations in reactor technologies. Indian innovative reactor 'AHWR' is a pressure-tube type natural circulation based boiling water reactor that is designed to meet such requirements, which essentially reflect the needs of next generation reactors. The reactor employs various passive features to prevent and mitigate accidental conditions, like a slightly negative void reactivity coefficient, passive poison injection to scram the reactor in event of failure of the wired shutdown systems, a large elevated pool of water as a heat sink inside the containment, passive decay heat removal based on natural circulation and passive valves, passive ECC injection, etc. It is designed to meet the fundamental safety requirements of safe shutdown, safe decay heat removal and confinement of activity with no impact in public domain, and hence, no need for emergency planning under all conceivable scenarios. This paper examines the role of the various passive safety systems in prevention and mitigation of severe plant conditions that may arise in event of multiple failures. For the purpose of demonstration of the effectiveness of its passive features, postulated scenarios on the lines of three major severe accidents in the history of nuclear power reactors are considered, namely; the Three Mile Island (TMI), Chernobyl and Fukushima accidents. Severe plant conditions along the lines of these scenarios are postulated to the extent conceivable in the reactor under consideration and analyzed using best estimate system thermal-hydraulics code RELAP5/Mod3.2. It is found that the various passive systems incorporated enable the reactor to tolerate the postulated accident conditions without causing severe plant conditions and core degradation.

ROLE OF PASSIVE SAFETY FEATURES IN PREVENTION AND MITIGATION OF SEVERE PLANT CONDITIONS IN INDIAN ADVANCED HEAVY WATER REACTOR

Directory of Open Access Journals (Sweden)

VIKAS JAIN

2013-10-01

Full Text Available Pressing demands of economic competitiveness, the need for large-scale deployment, minimizing the need of human intervention, and experience from the past events and incidents at operating reactors have guided the evolution and innovations in reactor technologies. Indian innovative reactor ‘AHWR’ is a pressure-tube type natural circulation based boiling water reactor that is designed to meet such requirements, which essentially reflect the needs of next generation reactors. The reactor employs various passive features to prevent and mitigate accidental conditions, like a slightly negative void reactivity coefficient, passive poison injection to scram the reactor in event of failure of the wired shutdown systems, a large elevated pool of water as a heat sink inside the containment, passive decay heat removal based on natural circulation and passive valves, passive ECC injection, etc. It is designed to meet the fundamental safety requirements of safe shutdown, safe decay heat removal and confinement of activity with no impact in public domain, and hence, no need for emergency planning under all conceivable scenarios. This paper examines the role of the various passive safety systems in prevention and mitigation of severe plant conditions that may arise in event of multiple failures. For the purpose of demonstration of the effectiveness of its passive features, postulated scenarios on the lines of three major severe accidents in the history of nuclear power reactors are considered, namely; the Three Mile Island (TMI, Chernobyl and Fukushima accidents. Severe plant conditions along the lines of these scenarios are postulated to the extent conceivable in the reactor under consideration and analyzed using best estimate system thermal-hydraulics code RELAP5/Mod3.2. It is found that the various passive systems incorporated enable the reactor to tolerate the postulated accident conditions without causing severe plant conditions and core degradation.

A Review of Mercury Exposure and Health of Dental Personnel

Directory of Open Access Journals (Sweden)

Natasha Nagpal

2017-03-01

Full Text Available Considerable effort has been made to address the issue of occupational health and environmental exposure to mercury. This review reports on the current literature of mercury exposure and health impacts on dental personnel. Citations were searched using four comprehensive electronic databases for articles published between 2002 and 2015. All original articles that evaluated an association between the use of dental amalgam and occupational mercury exposure in dental personnel were included. Fifteen publications from nine different countries met the selection criteria. The design and quality of the studies showed significant variation, particularly in the choice of biomarkers as an indicator of mercury exposure. In several countries, dental personnel had higher mercury levels in biological fluids and tissues than in control groups; some work practices increased mercury exposure but the exposure levels remained below recommended guidelines. Dental personnel reported more health conditions, often involving the central nervous system, than the control groups. Clinical symptoms reported by dental professionals may be associated with low-level, long-term exposure to occupational mercury, but may also be due to the effects of aging, occupational overuse, and stress. It is important that dental personnel, researchers, and educators continue to encourage and monitor good work practices by dental professionals.

Quantitative microbial risk assessment (QMRA) shows increased public health risk associated with exposure to river water under conditions of riverbed sediment resuspension

CSIR Research Space (South Africa)

Abia

2016-10-01

Full Text Available of The Total Environment, 556-557, pp 1143-1151 Quantitative microbial risk assessment (QMRA) shows increased public health risk associated with exposure to river water under conditions of riverbed sediment resuspension Akebe Luther King Abia a...

Treatment of severe non-infectious uveitis in high-risk conditions (Part I): pregnancy and malignancies, management and safety issues.

Science.gov (United States)

Cordero-Coma, Miguel; Salazar-Méndez, Raquel; Yilmaz, Taygan

2015-07-01

Management of patients with severe immune-mediated uveitis requires the use of immunosuppressive drugs in selected cases. This may be especially challenging in certain patients with concomitant conditions, which could increase the risk of side effects or modify guidelines for the use of such drugs. Therapeutic decision-making and management may be of particular difficulty in pregnancy as well as in patients with associated malignancies unrelated to a specific ophthalmic inflammatory condition. The main aim of this review is to provide an updated comprehensive practical guide for practitioners regarding the therapeutic decision-making and management of patients with severe immune-mediated uveitis in the context of pregnancy and malignancies. Management of patients with immune-mediated uveitis requiring immunosuppressive/immunomodulatory drugs might be particularly complicated by other conditions affecting their health and immune status. Clinicians should take into account such conditions, which might influence treatment response and the clinical outcome of these patients.

Effects of heavy metal exposure on the condition and health of adult great tits (Parus major)

International Nuclear Information System (INIS)

Dauwe, Tom; Janssens, Ellen; Eens, Marcel

2006-01-01

We examined the possible effects of heavy metal exposure on the quality and health of adult great tits (Parus major) at four study sites along a pollution gradient near a non-ferrous smelter in Belgium. Tarsus length, wing length, body mass and condition of great tits were compared with respect to study site, age (first-year and older great tits), sex and season (birds caught in winter and during breeding). Tarsus length did not differ significantly among study sites. The wing length of great tits was larger at the study site furthest from the smelter, especially for older great tits. The length of the outermost tail feathers, however, did not differ significantly among study sites. We found no signs of loss of body mass or condition towards the pollution source. The body mass and condition was lowest for female great tits at the site furthest from the smelter, especially during winter. Haematocrit values did not differ significantly among sites. Overall, we found no clear significant effects of heavy metal pollution on morphological measurements and health parameters of great tits. - Heavy metal pollution had no clear effect on condition and health, but this may have been masked by habitat quality differences and gene flow

Evaluation of environmental radiation exposure

International Nuclear Information System (INIS)

Imai, Kazuhiko

1974-01-01

The environmental radiation exposure due to radioactive rare gases is most important both at the time of reactor accidents and also in the long-term normal operation of reactor plants. The exposure dose is usually calculated by means of computers. The procedure of the calculation on environmental exposure dose is divided in several consecutive steps. The calculational formulae frequently used and those proposed recently are given with the explanation on released radionuclides, release to the atmosphere, concentration in the atmosphere, β-ray exposure, γ-ray exposure, and calculation of long-term exposure dose. (Mori, K.)

Hydroquinone PBPK model refinement and application to dermal exposure.

Science.gov (United States)

Poet, Torka S; Carlton, Betsy D; Deyo, James A; Hinderliter, Paul M

2010-11-01

A physiologically based pharmacokinetic (PBPK) model for hydroquinone (HQ) was refined to include an expanded description of HQ-glucuronide metabolites and a description of dermal exposures to support route-to-route and cross-species extrapolation. Total urinary excretion of metabolites from in vivo rat dermal exposures was used to estimate a percutaneous permeability coefficient (K(p); 3.6×10(-5) cm/h). The human in vivo K(p) was estimated to be 1.62×10(-4) cm/h, based on in vitro skin permeability data in rats and humans and rat in vivo values. The projected total multi-substituted glutathione (which was used as an internal dose surrogate for the toxic glutathione metabolites) was modeled following an exposure scenario based on submersion of both hands in a 5% aqueous solution of HQ (similar to black and white photographic developing solution) for 2 h, a worst-case exposure scenario. Total multi-substituted glutathione following this human dermal exposure scenario was several orders of magnitude lower than the internal total glutathione conjugates in rats following an oral exposure to the rat NOEL of 20 mg/kg. Thus, under more realistic human dermal exposure conditions, it is unlikely that toxic glutathione conjugates (primarily the di- and, to a lesser degree, the tri-glutathione conjugate) will reach significant levels in target tissues. Copyright © 2010. Published by Elsevier Ltd.

Metabolic responses of the isopod Porcellionides pruinosus to nickel exposure assessed by (1)H NMR metabolomics.

Science.gov (United States)

Ferreira, Nuno G C; Saborano, Raquel; Morgado, Rui; Cardoso, Diogo N; Rocha, Cláudia M; Soares, Amadeu M V M; Loureiro, Susana; Duarte, Iola F

2016-03-30

This work aimed at characterizing the metabolome of the isopod Porcellionides pruinosus and at assessing its variations over 14 days under laboratory culture conditions and upon exposure to the contaminant metal Nickel (Ni). The spectral profiles obtained by (1)H NMR spectroscopy were thoroughly assigned and subjected to multivariate analysis in order to highlight consistent changes. Over 50 metabolites could be identified, providing considerable new knowledge on the metabolome of these model organisms. Several metabolites changed non-linearly with Ni dose and exposure time, showing distinct variation patterns for initial (4 days) and later time points (7 and 14 days). In particular, at day 4, several amino acids were increased and sugars were decreased (compared to controls), whereas these variations were inverted for longer exposure, possibly reflecting earlier and more intensive moulting. Other variations, namely in betaines and choline-containing compounds, were suggested to relate with osmoregulation and detoxification mechanisms. Ni also had a marked effect on several nucleotides (increased upon exposure) and a moderate impact on lipids (decreased upon exposure). Overall, this study has provided new information on the Ni-induced metabolic adaptations of the P. pruinosus isopod, paving the way for improved mechanistic understanding of how these model organisms handle soil contamination. This study provided, for the first time to our knowledge, a detailed picture of the NMR-detectable metabolome of terrestrial isopods and of its fluctuations in time and upon exposure to the contaminant metal Nickel. Several time- and dose-dependent changes were highlighted, providing mechanistic insight into how these important model organisms handle Ni contamination.

Does heavy metal exposure affect the condition of Whitethroat (Sylvia communis) nestlings?

Science.gov (United States)

Turzańska-Pietras, Katarzyna; Chachulska, Justyna; Polechońska, Ludmiła; Borowiec, Marta

2018-03-01

Anthropogenic pollution results in high concentrations of heavy metals in the environment. Due to their persistence and a high potential for bioaccumulation, metals are a real threat for birds breeding in industrial areas. The aim of the present study has been to explore the contents of heavy metals (arsenic As, cadmium Cd, chromium Cr, copper Cu, iron Fe, nickel Ni, lead Pb and zinc Zn) in the excreta of Whitethroat (Sylvia communis) nestlings living in polluted environment and to investigate the relationship between these contents and the nestlings' condition. Excrement samples contained all the studied elements. The contents of arsenic, cadmium, copper and zinc in the excreta of nestlings from nests located close to a slag dump were several times higher than in the soil near the dump, which suggested accumulation in food consumed by the birds. Condition parameters (body mass and haemoglobin concentration) were not related to heavy metal concentrations in the nestlings' excreta, except of Zn. It is possible that Whitethroats are able to detoxicate heavy metals to a certain extent. Detailed, multi-element analysis of the environment, food and bird tissues or excreta should be performed to explore relations between different chemicals and bird condition.

Exposure of healthy subjects with emissions from a gas metal arc welding process: part 1--exposure technique and external exposure.

Science.gov (United States)

Brand, P; Havlicek, P; Steiners, M; Holzinger, K; Reisgen, U; Kraus, T; Gube, M

2013-01-01

Studies concerning welding fume-related adverse health effects in welders are hampered by the heterogeneity of workplace situations, resulting in complex and non-standardized exposure conditions. In order to carry out welding fume exposure studies under controlled and standardized conditions, the Aachen Workplace Simulation Laboratory was developed. This laboratory consists of an emission room, in which welding fume is produced, and an exposure room in which human subjects are exposed to these fumes. Both rooms are connected by a ventilation system which allows the welding fume concentration to be regulated. Particle mass concentration was measured with a TEOM microbalance and the particle number-size distribution using a Grimm SMPS device. In a study, which is the subject of this paper, it has been shown that welding fume concentration can easily be regulated between 1 and about 3 mg m(-3). The chosen concentration can be kept constant for more than 8 h. However, transport of the particles from the emission room into the exposure room leads to a change in particle size distribution, which is probably due to coagulation of the fraction of smallest particles. The Aachen Workplace Simulation Laboratory is suitable for controlled exposure studies with human subjects.

Assessment of exposure to chemical agents and ergonomic stressors in tanneries in Kanpur, India.

Science.gov (United States)

Ory, F G; Rahman, F U; Katagade, V; Shukla, A; Burdorf, A

1997-10-01

In developing countries qualitative assessment of exposure at the workplace may be an essential tool in evaluating hazardous working conditions. This survey reports on qualitative assessment of exposure to chemicals, dust, and ergonomic stressors among 298 workers in 15 tanneries in Kanpur, India. In general, chemical exposure and dermal exposure were highest among beamhouse workers, less for workers involved in dry finishing activities, and lowest for those performing the wet finishing of hides. Dermal exposure was rated as high to very high during beamhouse activities, reflecting direct contact with wet hides and manual handling of hides in soak tanks. Relevant dust exposure was observed only during dry finishing activities. Most workers experienced severe postural load due to working in trunk flexion and rotation for more than 50% of their daily work time. In addition, manual materials handling with loads over 20 kg frequently occurred. The size of the tannery, in general a reflection of state of technology, showed no systematic influence on exposure profiles. The survey suggested that mechanization of material transfer and application of trolleys reduced the work time with trunk flexion and rotation and implied less manual lifting. The presence of local exhaust ventilation in large tanneries seemed to reduce the chemical exposure. This survey has demonstrated the importance of rapid appraisal techniques for evaluating hazardous conditions at the workplace. In developing countries this approach may facilitate occupational hygiene research and practice.

Hypoxic conditioning as a new therapeutic modality

Directory of Open Access Journals (Sweden)

Samuel eVerges

2015-06-01

Full Text Available Preconditioning refers to a procedure by which a single noxious stimulus below the threshold of damage is applied to the tissue in order to increase resistance to the same or even different noxious stimuli given above the threshold of damage. Hypoxic preconditioning relies on complex and active defenses that organisms have developed to counter the adverse consequences of oxygen deprivation. The protection it confers against ischemic attack for instance as well as the underlying biological mechanisms have been extensively investigated in animal models. Based on these data, hypoxic conditioning (consisting in recurrent exposure to hypoxia has been suggested a potential non-pharmacological therapeutic intervention to enhance some physiological functions in individuals in whom acute or chronic pathological events are anticipated or existing. In addition to healthy subjects, some benefits have been reported in patients with cardiovascular and pulmonary diseases as well as in overweight and obese individuals. Hypoxic conditioning consisting in sessions of intermittent exposure to moderate hypoxia repeated over several weeks may induce hematological, vascular, metabolic and neurological effects. This review addresses the existing evidence regarding the use of hypoxic conditioning as a potential therapeutic modality and emphasizes on many remaining issues to clarify and future researches to be performed in the field.

Toxicity assessment of TiO2 nanoparticles in zebrafish embryos under different exposure conditions

International Nuclear Information System (INIS)

Clemente, Z.; Castro, V.L.S.S.; Moura, M.A.M.; Jonsson, C.M.; Fraceto, L.F.

2014-01-01

Highlights: •Nano-TiO 2 accelerated hatching of the larvae. •Exposure to anatase/rutile mixture under UV light altered the equilibrium and survival of the larvae. •Nano-TiO 2 caused alterations in the activities of CAT and GST. -- Abstract: The popularity of TiO 2 nanoparticles (nano-TiO 2 ) lies in their wide range of nanotechnological applications, together with low toxicity. Meanwhile, recent studies have shown that the photocatalytic properties of this material can result in alterations in their behavior in the environment, causing effects that have not yet been fully elucidated. The objective of this study was to evaluate the toxicity of two formulations of nano-TiO 2 under different illumination conditions, using an experimental model coherent with the principle of the three Rs of alternative animal experimentation (reduction, refinement, and replacement). Embryos of the fish Danio rerio were exposed for 96 h to different concentrations of nano-TiO 2 in the form of anatase (TA) or an anatase/rutile mixture (TM), under either visible light or a combination of visible and ultraviolet light (UV). The acute toxicity and sublethal parameters evaluated included survival rates, malformation, hatching, equilibrium, and overall length of the larvae, together with biochemical biomarkers (specific activities of catalase (CAT), glutathione S-transferase (GST), and acid phosphatase (AP)). Both TA and TM caused accelerated hatching of the larvae. Under UV irradiation, there was greater mortality of the larvae of the groups exposed to TM, compared to those exposed to TA. Exposure to TM under UV irradiation altered the equilibrium of the larvae. Alterations in the activities of CAT and GST were indicative of oxidative stress, although no clear dose-response relationship was observed. The effects of nano-TiO 2 appeared to depend on both the type of formulation and the illumination condition. The findings contribute to elucidation of the factors involved in the toxicity

Control Efficacy of Fungicides on Chinese Cabbage Clubroot under Several Conditions

Directory of Open Access Journals (Sweden)

Min-Yong Eom

2011-08-01

Full Text Available To develop the efficient screening methods for antifungal compound active to Chinese cabbage clubroot caused by Plasmodiophora brassicae, the control efficacy of three fungicides fluazinam, ethaboxam, and cyazofamid on the disease was tested under several conditions such as soil types, cultivars of Chinese cabbage, growth stages of the host, and inoculum concentrations. The in vivo antifungal activities of the fungicides on clubroot of two Chinese cabbage cultivars were hardly different. At 7- and 14-day-old seedlings, the fungicides were more effective to control of clubroot than at 21-day-old seedlings. In a commercial horticulture media soil (CNS, disease severity of untreated controls was higher and control activity of the fungicides was less than in a mixture of CNS and upland soil (1:1, v/v. Disease development of the seedlings inoculated with P. brassicae at 1.8×10(7 spores/pot to 1.1×10(9 spores/pot was almost same, but control efficacy of the fungicides was negatively correlated with inoculum dosages. To effectively select in vivo antifungal compound on Chinese cabbage clubroot, 14-day-old seedlings need to be inoculated with P. brassicae by drenching the spore suspension to give 1×10(8 spores/pot 1 day after chemical treatment. To develop clubroot, the inoculated plants are incubated in a growth chamber at 20℃ for 2 days, and then cultivated in a greenhouse (20±5℃ for four weeks.

Advertising exposures for a seasonal good in a segmented market

OpenAIRE

Daniela Favaretto; Luca Grosset; Bruno Viscolani

2011-01-01

The optimal control problem of determining advertising efforts for a seasonal good in a heterogeneous market is considered. We characterize optimal advertising exposures under different conditions: the general situation in which several wide-spectrum media are available, under the assumption of additive advertising effects on goodwill evolution, the ideal situation in which the advertising process can reach selectively each segment and the more realistic one in which a single medium reaches s...

CURRENT LEVELS OF MEDICAL EXPOSURE IN RUSSIA

Directory of Open Access Journals (Sweden)

M. I. Balonov

2015-01-01

Full Text Available We considered conditions of patients’ medical radiation exposure in Russian diagnostic radiology and nuclear medicine basing on the data of our own research, of the Unified system of individual dose control and of some relevant literature. We analyzed the data on the number of diagnostic examinations, patients’ individual and collective doses and their distribution by examination types. Time trends of the studied parameters are presented for the period between 1999 and 2013. Current level of Russian patients’ medical exposure is the lowest over the whole observation period and one of the lowest among the developed countries. The annual number of X-ray diagnostic examinations is 1.8 per capita. In 2013 median effective dose of medical exposure per capita in Russia was 0.45 mSv and median dose per procedure was 0.25 mSv. The major contribution to collective dose of medical exposure was from computed tomography and radiography; the largest individual doses were caused by interventional radiology, computed X-Ray and nuclear medicine tomographic examinations. The range of median doses comprises about four orders of magnitude, i.e. from several microSv in dental X-ray examinations up to several tens of milliSv in interventional and multistage tomographic examinations. The median effective dose of adult patients increases by about an order of magnitude with each transition from dental X-ray examinations to conventional radiology and further to computed tomography and interventional radiology examinations. During interventional X-Ray examinations, absorbed skin doses at radiation beam entrance site may reach several Gray, which may lead to deterministic radiation effects in skin and subcutaneous tissues. Due to replacement of low-dose ‘functional’ nuclear medicine examinations with more informative modern scintigraphy and tomography examination, patient doses substantially increased over the last decade. With current trend for re-equipment of

Air pollution and asthma severity in adults

Science.gov (United States)

Rage, Estelle; Siroux, Valérie; Künzli, Nino; Pin, Isabelle; Kauffmann, Francine

2009-01-01

Objectives There is evidence that exposure to air pollution affects asthma, but the effect of air pollution on asthma severity has not been addressed. The aim was to assess the relation between asthma severity during the past 12 months and home outdoor concentrations of air pollution. Methods Asthma severity over the last 12 months was assessed in two complementary ways among 328 adult asthmatics from the French Epidemiological study on the Genetics and Environment of Asthma (EGEA) examined between 1991 and 1995. The 4-class severity score integrated clinical events and type of treatment. The 5-level asthma score is based only on the occurrence of symptoms. Nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3) concentrations were assigned to each residence using two different methods. The first was based on the closest monitor data from 1991–1995. The second consisted in spatial models that used geostatistical interpolations and then assigned air pollutants to the geo-coded residences (1998). Results Higher asthma severity score was significantly related to the 8-hour average of ozone during April-September (O3-8hr) and the number of days (O3-days) with 8-hour ozone averages above 110 μg.m−3 (for a 36-day increase, equivalent to the inter quartile range, in O3-days, odds ratio (95% confidence interval) 2.22 (1.61–3.07) for one class difference in score). Adjustment for age, sex, smoking habits, occupational exposure, and educational level did not alter results. Asthma severity was unrelated to NO2. Both exposure assessment methods and severity scores resulted in very similar findings. SO2 correlated with severity but reached statistical significance only for the model based assignment of exposure. Conclusions The observed associations between asthma severity and air pollution, in particular O3, support the hypothesis that air pollution at levels far below current standards increases asthma severity. PMID:19017701

Evaluation of the single radiosensitivity in patients subjected to medical exposure that show severe skin reactions

International Nuclear Information System (INIS)

Di Giorgio, M.; Vallerga, M.B.; Portas, M.; Perez, M.R.

2006-01-01

The Burnt Hospital of the Buenos Aires City Government (HQGCBA) it is a hospital of reference of the Net of Medical Responses in Radiological Emergencies of the Argentine Republic. In the mark of an agreement among the HQGCBA and the Authority Regulatory Nuclear (ARN), it is in execution a study protocol for the one boarding diagnoses and therapeutic of radioinduced cutaneous leisure. They exist individual variations that can condition the response to the ionizing radiations (IR), so much in accidental exposures as having programmed (radiotherapy, radiology interventionist). In this context, the individual radiosensitivity is evaluated in the patients signed up in this protocol that presented sharp or late cutaneous reactions, with grades of severity 3-4 (approaches EORTC/RTOG). The capacity of repair of the DNA was evaluated in outlying blood lymphocytes irradiated in vitro (2 Gy, gamma of Co-60) by means of the micronucleus techniques and comet essay in alkaline conditions. In this work two cases in those that is applied this study protocol, the therapeutic answer and its correlate with the discoveries of the radiosensitivity tests is presented. Case 1: patient of feminine sex, subjected to external radiotherapy by a breast infiltrating ductal carcinoma; developed sharp cutaneous radiotoxicity grade 3 (confluent humid epithelitis) that motivate the interruption of the treatment. Case 2: patient of masculine sex, subjected to a coronary angioplasty (interventionist radiology); developed late cutaneous radiotoxicity grade 4 (ulceration in dorsal region). Both patients were treated with topical trolamine associated to systemic administration of pentoxiphiline and antioxidants. The therapeutic answer is evaluated by means of clinical pursuit, photographic serial register and complementary exams (thermography and ultrasonography of high frequency). In the case 1 the answer was very favorable, with precocious local improvement and complete remission of symptoms and

Detrimental effects of environmental tobacco smoke in relation to asthma severity.

Directory of Open Access Journals (Sweden)

Suzy A A Comhair

2011-05-01

Full Text Available Environmental tobacco smoke (ETS has adverse effects on the health of asthmatics, however the harmful consequences of ETS in relation to asthma severity are unknown.In a multicenter study of severe asthma, we assessed the impact of ETS exposure on morbidity, health care utilization and lung functions; and activity of systemic superoxide dismutase (SOD, a potential oxidative target of ETS that is negatively associated with asthma severity.From 2002-2006, 654 asthmatics (non-severe 366, severe 288 were enrolled, among whom 109 non-severe and 67 severe asthmatics were routinely exposed to ETS as ascertained by history and validated by urine cotinine levels. ETS-exposure was associated with lower quality of life scores; greater rescue inhaler use; lower lung function; greater bronchodilator responsiveness; and greater risk for emergency room visits, hospitalization and intensive care unit admission. ETS-exposure was associated with lower levels of serum SOD activity, particularly in asthmatic women of African heritage.ETS-exposure of asthmatic individuals is associated with worse lung function, higher acuity of exacerbations, more health care utilization, and greater bronchial hyperreactivity. The association of diminished systemic SOD activity to ETS exposure provides for the first time a specific oxidant mechanism by which ETS may adversely affect patients with asthma.

Potential for containment leak paths through electrical penetration assemblies under severe accident conditions

International Nuclear Information System (INIS)

Sebrell, W.

1983-07-01

The leakage behavior of containments beyond design conditions and knowledge of failure modes is required for evaluation of mitigation strategies for severe accidents, risk studies, emergency preparedness planning, and siting. These studies are directed towards assessing the risk and consequences of severe accidents. An accident sequence analysis conducted on a Boiling Water Reactor (BWR), Mark I (MK I), indicated very high temperatures in the dry-well region, which is the location of the majority of electrical penetration assemblies. Because of the high temperatures, it was postulated in the ORNL study that the sealants would fail and all the electrical penetration assemblies would leak before structural failure would occur. Since other containments had similar electrical penetration assemblies, it was concluded that all containments would experience the same type of failure. The results of this study, however, show that this conclusion does not hold for PWRs because in the worst accident sequence, the long time containment gases stabilize to 350 0 F. BWRs, on the other hand, do experience high dry-well temperatures and have a higher potential for leakage

Cancer risks following diagnostic and therapeutic radiation exposure in children

Energy Technology Data Exchange (ETDEWEB)

Kleinerman, Ruth A. [National Institutes of Health, Division of Cancer Epidemiology and Genetics, National Cancer Institute, EPS 7044, Rockville, MD (United States)

2006-09-15

The growing use of interventional and fluoroscopic imaging in children represents a tremendous benefit for the diagnosis and treatment of benign conditions. Along with the increasing use and complexity of these procedures comes concern about the cancer risk associated with ionizing radiation exposure to children. Children are considerably more sensitive to the carcinogenic effects of ionizing radiation than adults, and children have a longer life expectancy in which to express risk. Numerous epidemiologic cohort studies of childhood exposure to radiation for treatment of benign diseases have demonstrated radiation-related risks of cancer of the thyroid, breast, brain and skin, as well as leukemia. Many fewer studies have evaluated cancer risk following diagnostic radiation exposure in children. Although radiation dose for a single procedure might be low, pediatric patients often receive repeated examinations over time to evaluate their conditions, which could result in relatively high cumulative doses. Several cohort studies of girls and young women subjected to multiple diagnostic radiation exposures have been informative about increased mortality from breast cancer with increasing radiation dose, and case-control studies of childhood leukemia and postnatal diagnostic radiation exposure have suggested increased risks with an increasing number of examinations. Only two long-term follow-up studies of cancer following cardiac catheterization in childhood have been conducted, and neither reported an overall increased risk of cancer. Most cancers can be induced by radiation, and a linear dose-response has been noted for most solid cancers. Risks of radiation-related cancer are greatest for those exposed early in life, and these risks appear to persist throughout life. (orig.)

Cancer risks following diagnostic and therapeutic radiation exposure in children

International Nuclear Information System (INIS)

Kleinerman, Ruth A.

2006-01-01

The growing use of interventional and fluoroscopic imaging in children represents a tremendous benefit for the diagnosis and treatment of benign conditions. Along with the increasing use and complexity of these procedures comes concern about the cancer risk associated with ionizing radiation exposure to children. Children are considerably more sensitive to the carcinogenic effects of ionizing radiation than adults, and children have a longer life expectancy in which to express risk. Numerous epidemiologic cohort studies of childhood exposure to radiation for treatment of benign diseases have demonstrated radiation-related risks of cancer of the thyroid, breast, brain and skin, as well as leukemia. Many fewer studies have evaluated cancer risk following diagnostic radiation exposure in children. Although radiation dose for a single procedure might be low, pediatric patients often receive repeated examinations over time to evaluate their conditions, which could result in relatively high cumulative doses. Several cohort studies of girls and young women subjected to multiple diagnostic radiation exposures have been informative about increased mortality from breast cancer with increasing radiation dose, and case-control studies of childhood leukemia and postnatal diagnostic radiation exposure have suggested increased risks with an increasing number of examinations. Only two long-term follow-up studies of cancer following cardiac catheterization in childhood have been conducted, and neither reported an overall increased risk of cancer. Most cancers can be induced by radiation, and a linear dose-response has been noted for most solid cancers. Risks of radiation-related cancer are greatest for those exposed early in life, and these risks appear to persist throughout life. (orig.)

Guidance of reactor operators and TSC personnel with the severe accident management guidance under shutdown and low power conditions

International Nuclear Information System (INIS)

Van Haesendonck, M.F.; Prior, R.P.

2000-01-01

The Westinghouse Owners Group Severe Accident Management Guidance (WOG SAMG) was developed between 1991 and 1994. The primary goals for severe accident management that form the basis of the WOG SAMG are to terminate any radioactive releases to the environment; to prevent failure of any containment fission product boundary and to return the plant to a controlled stable condition. The WOG SAMG is primarily a TSC tool for mitigation of low probability core damage events. The philosophy is that control room operators should remain focused on the prevention of core damage, whereas the TSC personnel should concentrate on the mitigation of the severe accident. The symptom based package is built up as a structured process for choosing appropriate actions based on actual plant conditions. No detailed knowledge of severe accident phenomena is required. The scope of the WOG SAMG is limited to severe accidents resulting from initiating events occurring during full power operation. However, a number of studies such as the EdF EPS 1300 Probabilistic Safety Assessment (PSA), the shutdown Probabilistic Risk Assessment (PRA) for Surry, the BERA shutdown PRA for Beznau, the EPRI/ Westinghouse ORAM methodology etc. have shown that the frequency of core damage (a severe accident) during shutdown and low power operation can be of the same order of magnitude as for full power operation. The at-power SAMG is viewed as the resolution of the severe accident issue. Similarly, it is expected that as shutdown PRAs mature, the final resolution of the severe accident issue will lie in SAMG for low power and shutdown operation. Therefore in resolution of this issue, Westinghouse has developed the Shutdown Severe Accident Management Guidance (SSAMG) which gives guidance for both control room and TSC personnel to mitigate a severe accident under shutdown or low power conditions. In the last few years, many LWR plants have been implementing SAMG. In the US, all plants have developed SAMG, and many

Assessment of exposure pathways connected with construction and operation of concrete bridge reinforced with very low level radioactive steel

International Nuclear Information System (INIS)

Panik, M.; Necas, V.

2012-01-01

Large amount of low level radioactive material arises during decommissioning of nuclear power plants. Material mostly comprises metal scrap and concrete ruble. Paper deals with recycling and reuse of metal scrap and its utilization as part of reinforcement of concrete bridges under the conditional release concept. Radiation exposure originating in very low level reinforcement steel consists of several exposure pathways. Short-term radiation impact is represented mostly by external exposure pathway and it is relevant to the construction workers and users of the bridge. Long-term radiation impacts on inhabitants living near finished bridge and it is divided into inhalation and ingestion of radionuclides-internal exposure pathways. Radiation impact caused by utilization of very low level radioactive waste was calculated using simulation software VISIPLAN 3D ALARA and GOLDSIM. Results of calculations provide fair summary of possibilities of utilization of conditionally released steel as reinforcement of concrete bridges. (Authors)

EXPOSURE TO MASS MEDIA AS A DOMINANT FACTOR INFLUENCING PUBLIC STIGMA TOWARD MENTAL ILLNESS BASED ON SUNRISE MODEL APPROACH

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Ni Made Sintha Pratiwi

2018-05-01

Full Text Available Background: The person suffering mental disorders is not only burdened by his condition but also by the stigma. The impact of stigma extremely influences society that it is considered to be the obstacle in mental disorders therapy. Stigma as the society adverse view toward severe mental disorders is related with the cultural aspect. The interaction appeared from each component of nursing model namely sunrise model, which a model developed by Madeleine Leininger is connected with the wide society views about severe mental disorders condition in society. Objective: The aim of this study was to analyze the factors related to public stigma and to find out the dominant factors related to public stigma about severe mental illness through sunrise model approach in Sukonolo Village, Malang Regency. Methods: This study using observational analytical design with cross sectional approach. There were 150 respondents contributed in this study. The respondents were obtained using purposive sampling technique. Results: The results showed a significant relationship between mass media exposure, spiritual well-being, interpersonal contact, attitude, and knowledge with public stigma about mental illness. The result from multiple logistic regression shows the low exposure of mass media has the highest OR value at 26.744. Conclusion: There were significant correlation between mass media exposure, spiritual well-being, interpersonal contact, attitude, and knowledge with public stigma toward mental illness. Mass media exposure as a dominant factor influencing public stigma toward mental illness.

Modelling the effects of pulse exposure of several PSII inhibitors on two algae.

Science.gov (United States)

Copin, Pierre-Jean; Chèvre, Nathalie

2015-10-01

Subsequent to crop application and during precipitation events, herbicides can reach surface waters in pulses of high concentrations. These pulses can exceed the Annual Average Environmental Quality Standards (AA-EQS), defined in the EU Water Framework Directive, which aims to protect the aquatic environment. A model was developed in a previous study to evaluate the effects of pulse exposure for the herbicide isoproturon on the alga Scenedesmus vacuolatus. In this study, the model was extended to other substances acting as photosystem II inhibitors and to other algae. The measured and predicted effects were equivalent when pulse exposure of atrazine and diuron were tested on S. vacuolatus. The results were consistent for isoproturon on the alga Pseudokirchneriella subcapitata. The model is thus suitable for the effect prediction of phenylureas and triazines and for the algae used: S. vacuolatus and P. subcapitata. The toxicity classification obtained from the dose-response curves (diuron>atrazine>isoproturon) was conserved for the pulse exposure scenarios modelled for S. vacuolatus. Toxicity was identical for isoproturon on the two algae when the dose-response curves were compared and also for the pulse exposure scenarios. Modelling the effects of any pulse scenario of photosystem II inhibitors on algae is therefore feasible and only requires the determination of the dose-response curves of the substance and growth rate of unexposed algae. It is crucial to detect the longest pulses when measurements of herbicide concentrations are performed in streams because the model showed that they principally affect the cell density inhibition of algae. Copyright © 2015 Elsevier Ltd. All rights reserved.

Characterization of biological aerosol exposure risks from automobile air conditioning system.

Science.gov (United States)

Li, Jing; Li, Mingzhen; Shen, Fangxia; Zou, Zhuanglei; Yao, Maosheng; Wu, Chang-yu

2013-09-17

Although use of automobile air conditioning (AC) was shown to reduce in-vehicle particle levels, the characterization of its microbial aerosol exposure risks is lacking. Here, both AC and engine filter dust samples were collected from 30 automobiles in four different geographical locations in China. Biological contents (bacteria, fungi, and endotoxin) were studied using culturing, high-throughput gene sequence, and Limulus amebocyte lysate (LAL) methods. In-vehicle viable bioaerosol concentrations were directly monitored using an ultraviolet aerodynamic particle sizer (UVAPS) before and after use of AC for 5, 10, and 15 min. Regardless of locations, the vehicle AC filter dusts were found to be laden with high levels of bacteria (up to 26,150 CFU/mg), fungi (up to 1287 CFU/mg), and endotoxin (up to 5527 EU/mg). More than 400 unique bacterial species, including human opportunistic pathogens, were detected in the filter dusts. In addition, allergenic fungal species were also found abundant. Surprisingly, unexpected fluorescent peaks around 2.5 μm were observed during the first 5 min use of AC, which was attributed to the reaerosolization of those filter-borne microbial agents. The information obtained here can assist in minimizing or preventing the respiratory allergy or infection risk from the use of automobile AC system.

Non-Smoker Exposure to Secondhand Cannabis Smoke II: Effect of Room Ventilation on the Physiological, Subjective, and Behavioral/Cognitive Effects

Science.gov (United States)

Herrmann, Evan S.; Cone, Edward J; Mitchell, John M.; Bigelow, George E.; LoDico, Charles; Flegel, Ron; Vandrey, Ryan

2015-01-01

Introduction Cannabis is the most widely used illicit drug. Many individuals are incidentally exposed to secondhand cannabis smoke, but little is known about the effects of this exposure. This report examines the physiological, subjective, and behavioral/cognitive effects of secondhand cannabis exposure, and the influence of room ventilation on these effects. Methods Non-cannabis-using individuals were exposed to secondhand cannabis smoke from six individuals smoking cannabis (11.3% THC) ad libitum in a specially constructed chamber for one hour. Chamber ventilation was experimentally manipulated so that participants were exposed under unventilated conditions or with ventilation at a rate of 11 air exchanges/hour. Physiological, subjective and behavioral/cognitive measures of cannabis exposure assessed after exposure sessions were compared to baseline measures. Results Exposure to secondhand cannabis smoke under unventilated conditions produced detectable cannabinoid levels in blood and urine, minor increases in heart rate, mild to moderate self-reported sedative drug effects, and impaired performance on the Digit Symbol Substitution Task (DSST). One urine specimen tested positive at using a 50 ng/mL cut-off and several specimens were positive at 20 ng/mL. Exposure under ventilated conditions resulted in much lower blood cannabinoid levels, and did not produce sedative drug effects, impairments in performance, or positive urine screen results. Conclusions Room ventilation has a pronounced effect on exposure to secondhand cannabis smoke. Under extreme, unventilated conditions, secondhand cannabis smoke exposure can produce detectable levels of THC in blood and urine, minor physiological and subjective drug effects, and minor impairment on a task requiring psychomotor ability and working memory. PMID:25957157

Limit strains for severe accident conditions. Synthesis report of the EU-project LISSAC

International Nuclear Information System (INIS)

Krieg, R.; Seidenfuss, M.

2003-10-01

The local failure strains of essential reactor vessel components are investigated. The size influence of the components is of special interest. Typical severe accident conditions including elevated temperatures and dynamic loads are considered. The main part of work consists of test families with specimens under uniaxial and biaxial static and dynamic loads. Within one test family the specimen geometry and the load conditions are similar, the temperature is the same; but the size is varied up to reactor dimensions. Special attention is given to geometries with a hole or a notch causing non-uniform stress and strain distributions typical for reactor components. To manufacture all specimens sufficient material was available from the unused reactor pressure vessel Biblis C. Thus variations of the mechanical material properties, which could impair the interpretation of the test results, are rather small. This has been confirmed by an adequate number of additional quality assurance tests. A key problem was to determine the local strain at failure. Here suitable methods had to be developed including the so-called ''vanishing gap method'' and the ''forging die method''. They are based on post test geometrical measurements of the fracture surfaces and reconstructions of the related strain fields using finite element calculations, for instance. To deepen the understanding of structural degradation and fracture and to allow extrapolations, advanced computational methods including damage models have been developed and validated. Several approaches were tried in parallel including so-called non-local concepts and descriptions of stochastic properties at grain size level. The experimental results indicate that stresses versus dimensionless deformations are approximately size independent up to failure for specimens of similar geometry under similar load conditions. Also the maximum stress is approximately size independent, if failure occurs after the maximum stress is reached

Determinants of dermal exposure relevant for exposure modelling in regulatory risk assessment.

Science.gov (United States)

Marquart, J; Brouwer, D H; Gijsbers, J H J; Links, I H M; Warren, N; van Hemmen, J J

2003-11-01

Risk assessment of chemicals requires assessment of the exposure levels of workers. In the absence of adequate specific measured data, models are often used to estimate exposure levels. For dermal exposure only a few models exist, which are not validated externally. In the scope of a large European research programme, an analysis of potential dermal exposure determinants was made based on the available studies and models and on the expert judgement of the authors of this publication. Only a few potential determinants appear to have been studied in depth. Several studies have included clusters of determinants into vaguely defined parameters, such as 'task' or 'cleaning and maintenance of clothing'. Other studies include several highly correlated parameters, such as 'amount of product handled', 'duration of task' and 'area treated', and separation of these parameters to study their individual influence is not possible. However, based on the available information, a number of determinants could clearly be defined as proven or highly plausible determinants of dermal exposure in one or more exposure situation. This information was combined with expert judgement on the scientific plausibility of the influence of parameters that have not been extensively studied and on the possibilities to gather relevant information during a risk assessment process. The result of this effort is a list of determinants relevant for dermal exposure models in the scope of regulatory risk assessment. The determinants have been divided into the major categories 'substance and product characteristics', 'task done by the worker', 'process technique and equipment', 'exposure control measures', 'worker characteristics and habits' and 'area and situation'. To account for the complex nature of the dermal exposure processes, a further subdivision was made into the three major processes 'direct contact', 'surface contact' and 'deposition'.

External radiation exposure of the public

International Nuclear Information System (INIS)

Mehl, J.

1977-01-01

Results of several ten thousand measurements on external radiation (outside buildings, in living rooms) are used for illustrating by isodose charts covering the total area of the Federal Republic of Germany the exposure of the public from external radiation originating from natural radiation of the environment. Results of calculations on external radiation exposure of the public due to releases of radioactivity in air from nuclear installations are used for illustrating by coloured isodose charts the exposure of the public in the plant site vicinity. From comparison of the exposure levels it becomes obvious that if exposure levels of several 10 mrem per year are considered to be of real concern to public health, control of natural radoactivity in the environment of man would require more attention than present and foreseeable releases of radioactivity in air from nuclear inst

Reduced persistence of the macrolide antibiotics erythromycin, clarithromycin and azithromycin in agricultural soil following several years of exposure in the field

Energy Technology Data Exchange (ETDEWEB)

Topp, Edward, E-mail: ed.topp@agr.gc.ca; Renaud, Justin; Sumarah, Mark; Sabourin, Lyne

2016-08-15

The macrolide antibiotics erythromycin, clarithromycin and azithromycin are very important in human and animal medicine, and can be entrained onto agricultural ground through application of sewage sludge or manures. In the present study, a series of replicated field plots were left untreated or received up to five annual spring applications of a mixture of three drugs to achieve a nominal concentration for each of 10 or 0.1 mg kg{sup −1} soil; the latter an environmentally relevant concentration. Soil samples were incubated in the laboratory, and supplemented with antibiotics to establish the dissipation kinetics of erythromycin and clarithromycin using radioisotope methods, and azithromycin using HPLC-MS/MS. All three drugs were dissipated significantly more rapidly in soils with a history of field exposure to 10 mg kg{sup −1} macrolides, and erythromycin and clarithromycin were also degraded more rapidly in field soil exposed to 0.1 mg kg{sup −1} macrolides. Rapid mineralization of {sup 14}C-labelled erythromycin and clarithromycin are consistent with biodegradation. Analysis of field soils revealed no carryover of parent compound from year to year. Azithromycin transformation products were detected consistent with removal of the desosamine and cladinose moieties. Overall, these results have revealed that following several years of exposure to macrolide antibiotics these are amenable to accelerated degradation. The potential accelerated degradation of these drugs in soils amended with manure and sewage sludge should be investigated as this phenomenon would attenuate environmental exposure and selection pressure for clinically relevant resistance. - Highlights: • The impact of field exposure on persistence of macrolide antibiotics was evaluated. • Soil samples were incubated in the laboratory with macrolides. • Field exposure resulted in more rapid dissipation of all macrolides. • Radiolabelled erythromycin and clarithromycin were rapidly mineralized

Reduced persistence of the macrolide antibiotics erythromycin, clarithromycin and azithromycin in agricultural soil following several years of exposure in the field

International Nuclear Information System (INIS)

Topp, Edward; Renaud, Justin; Sumarah, Mark; Sabourin, Lyne

2016-01-01

The macrolide antibiotics erythromycin, clarithromycin and azithromycin are very important in human and animal medicine, and can be entrained onto agricultural ground through application of sewage sludge or manures. In the present study, a series of replicated field plots were left untreated or received up to five annual spring applications of a mixture of three drugs to achieve a nominal concentration for each of 10 or 0.1 mg kg"−"1 soil; the latter an environmentally relevant concentration. Soil samples were incubated in the laboratory, and supplemented with antibiotics to establish the dissipation kinetics of erythromycin and clarithromycin using radioisotope methods, and azithromycin using HPLC-MS/MS. All three drugs were dissipated significantly more rapidly in soils with a history of field exposure to 10 mg kg"−"1 macrolides, and erythromycin and clarithromycin were also degraded more rapidly in field soil exposed to 0.1 mg kg"−"1 macrolides. Rapid mineralization of "1"4C-labelled erythromycin and clarithromycin are consistent with biodegradation. Analysis of field soils revealed no carryover of parent compound from year to year. Azithromycin transformation products were detected consistent with removal of the desosamine and cladinose moieties. Overall, these results have revealed that following several years of exposure to macrolide antibiotics these are amenable to accelerated degradation. The potential accelerated degradation of these drugs in soils amended with manure and sewage sludge should be investigated as this phenomenon would attenuate environmental exposure and selection pressure for clinically relevant resistance. - Highlights: • The impact of field exposure on persistence of macrolide antibiotics was evaluated. • Soil samples were incubated in the laboratory with macrolides. • Field exposure resulted in more rapid dissipation of all macrolides. • Radiolabelled erythromycin and clarithromycin were rapidly mineralized. • Macrolides

Changes in thermo-tolerance and survival under simulated gastrointestinal conditions of Salmonella Enteritidis PT4 and Salmonella Typhimurium PT4 in chicken breast meat after exposure to sequential stresses.

Science.gov (United States)

Melo, Adma Nadja Ferreira de; Souza, Geany Targino de; Schaffner, Donald; Oliveira, Tereza C Moreira de; Maciel, Janeeyre Ferreira; Souza, Evandro Leite de; Magnani, Marciane

2017-06-19

This study assessed changes in thermo-tolerance and capability to survive to simulated gastrointestinal conditions of Salmonella Enteritidis PT4 and Salmonella Typhimurium PT4 inoculated in chicken breast meat following exposure to stresses (cold, acid and osmotic) commonly imposed during food processing. The effects of the stress imposed by exposure to oregano (Origanum vulgare L.) essential oil (OVEO) on thermo-tolerance were also assessed. After exposure to cold stress (5°C for 5h) in chicken breast meat the test strains were sequentially exposed to the different stressing substances (lactic acid, NaCl or OVEO) at sub-lethal amounts, which were defined considering previously determined minimum inhibitory concentrations, and finally to thermal treatment (55°C for 30min). Resistant cells from distinct sequential treatments were exposed to simulated gastrointestinal conditions. The exposure to cold stress did not result in increased tolerance to acid stress (lactic acid: 5 and 2.5μL/g) for both strains. Cells of S. Typhimurium PT4 and S. Enteritidis PT4 previously exposed to acid stress showed higher (pthermo-tolerance in both strains. The cells that survived the sequential stress exposure (resistant) showed higher tolerance (pthermo-tolerance and enhance the survival under gastrointestinal conditions of S. Enteritidis PT4 and S. Typhimurium PT4. Copyright © 2017 Elsevier B.V. All rights reserved.

Open-field exposure facilitates consummatory extinction.

Science.gov (United States)

Justel, Nadia; Psyrdellis, Mariana; Pautassi, Ricardo M

2016-12-07

During extinction, the organism learns that a conditioned stimulus or a conditioned response is no longer associated with an unconditioned stimulus, and as a consequence, a decrement in the response is presented. The exposure to novel situations (e.g. exploration of a novel open field) has been used widely to modulate (i.e. either enhance or deteriorate) learning and memory. The aim of the present study was to test whether open-field exposure could modulate consummatory extinction. The results indicated that open-field exposure accelerated the extinction response (i.e. experimental animals provided novelty exposure had lower consummatory behavior than control animals) when applied before - but not after - the first extinction trial, or when applied before the second extinction trial. The results suggest that environmental treatments such as novelty exposure provide a valuable, nonpharmacological alternative to potentially modulate extinction processes.

Combat exposure severity as a moderator of genetic and environmental liability to post-traumatic stress disorder.

Science.gov (United States)

Wolf, E J; Mitchell, K S; Koenen, K C; Miller, M W

2014-05-01

Twin studies of veterans and adults suggest that approximately 30-46% of the variance in post-traumatic stress disorder (PTSD) is attributable to genetic factors. The remaining variance is attributable to the non-shared environment, which, by definition, includes combat exposure. This study used a gene by measured environment twin design to determine whether the effects of genetic and environmental factors that contribute to the etiology of PTSD are dependent on the level of combat exposure. The sample was drawn from the Vietnam Era Twin Registry (VETR) and included 620 male-male twin pairs who served in the US Military in South East Asia during the Vietnam War era. Analyses were based on data from a clinical diagnostic interview of lifetime PTSD symptoms and a self-report measure of combat exposure. Biometric modeling revealed that the effects of genetic and non-shared environment factors on PTSD varied as a function of level of combat exposure such that the association between these factors and PTSD was stronger at higher levels of combat exposure. Combat exposure may act as a catalyst that augments the impact of hereditary and environmental contributions to PTSD. Individuals with the greatest exposure to combat trauma were at increased risk for PTSD as a function of both genetic and environmental factors. Additional work is needed to determine the biological and environmental mechanisms driving these associations.

At the Roots of Product Placement: The Mere Exposure Effect

Directory of Open Access Journals (Sweden)

Stefano Ruggieri

2013-05-01

Full Text Available The present study aims to analyze the effect of product placement on attitude change and takes into consideration psychological models of the mere exposure effect. A sample of high school students watched an excerpt from two widely-distributed movies in which several products were shown by using the technique known as product placement. The results indicate that students who saw the commercial brand liked the products more than those who didn’t see it. This effect, in line with the literature on the product placement effect, seems to be independent from the recognition of the brand in the movie excerpt. This study also shows that, in the high involvement condition, one exposure is enough to produce a positive attitude toward the brand.

N,N-dimethylformamide--influence of working conditions and skin penetration on the internal exposure of workers in synthetic textile production.

Science.gov (United States)

Wrbitzky, R; Angerer, J

1998-07-01

This study examined the external and internal exposure to the solvent N,N-dimethylformamide (DMF) of 126 workers from a factory producing synthetic fibers. Air measurements were carried out using personal air samplers with diffusion tubes (Drager, ORSA 5). For the purpose of biological monitoring the levels of N-methylformamide (NMF) in urine were measured in preshift and postshift samples. Determinations were carried out using gas chromatography. Anamnestic data were collected with standardized questionnaires, including personal data, working history and current working conditions, and former and current illness with regard to the effects of DMF. Skin diseases were documented by a dermatologist. DMF concentrations measured in the air ranged between work areas. The German BAT value (15 mg NMF/l urine) was exceeded in 36 persons (29%) despite the use of breathing protection and protective gloves, without increased values being measured in the air. Increased absorption without higher-level exposure could particularly also be observed in employees with eczema. From the point of view of the prevention of disease, biological monitoring is the best instrument for exposure assessment of workers exposed to DMF.

Radiologic exposure conditions and resultant skin doses in application of xeroradiography to the orthodontic diagnosis

International Nuclear Information System (INIS)

Nakasima, A.; Nakata, S.; Shimizu, K.; Takahama, Y.

1980-01-01

Xeroradiography is the recording of radiologic image by a photoelectric process rather than the photochemical one used in conventional radiography. In order to investigate the advantages and disadvantages of xeroradiography in the orthodontic field, minimum xeroradiologic exposure conditions for skull projections, joint projections, and hand projections were established by thirteen examiners and the relationship between the image production and x-ray radiation was compared with conventional film techniques. The advantages of xeroradiograph were finer and clear images caused by the edge effect and wide latitude of xeroradiography; the main hazard was the unavoidable larger skin dose required by the projection procedures. The skin doses with xeroradiography were 2.4 to 16.2 times larger than those with conventional film techniques

Investigation of the effect of UV-LED exposure conditions on the production of vitamin D in pig skin

DEFF Research Database (Denmark)

Barnkob, Line Lundbæk; Argyraki, Aikaterini; Petersen, Paul Michael

2016-01-01

study the exposure conditions with ultraviolet (UV) LEDs were systematically investigated in the wavelength range 280-340 nm for achieving optimal vitamin D bio-fortification in pig skin. A wavelength of 296 nm was found to be optimal for vitamin D3 production. The maximum dose of 20 kJ/m2 produced 3.......5-4 µg vitamin D3/cm2 pig skin. Vitamin D3 produced was independent on the combination of time and intensity of the LED source. The increased UV exposure by UV-LEDs may be readily implemented in existing food production facilities, without major modifications to the process or processing equipment......The dietary intake of vitamin D is currently below the recommended intake of 10-20 µg vitamin D/day. Foods with increased content of vitamin D or new products with enhanced vitamin D are warranted. Light-emitting diodes (LEDs) are a potential new resource in food production lines. In the present...

Novel biomarkers of perchlorate exposure in zebrafish

Science.gov (United States)

Mukhi, S.; Carr, J.A.; Anderson, T.A.; Patino, R.

2005-01-01

Perchlorate inhibits iodide uptake by thyroid follicles and lowers thyroid hormone production. Although several effects of perchlorate on the thyroid system have been reported, the utility of these pathologies as markers of environmental perchlorate exposures has not been adequately assessed. The present study examined time-course and concentration-dependent effects of perchlorate on thyroid follicle hypertrophy, colloid depletion, and angiogenesis; alterations in whole-body thyroxine (T4) levels; and somatic growth and condition factor of subadult and adult zebrafish. Changes in the intensity of the colloidal T4 ring previously observed in zebrafish also were examined immunohistochemically. Three-month-old zebrafish were exposed to ammonium perchlorate at measured perchlorate concentrations of 0, 11, 90, 1,131, and 11,480 ppb for 12 weeks and allowed to recover in clean water for 12 weeks. At two weeks of exposure, the lowest-observed-effective concentrations (LOECs) of perchlorate that induced angiogenesis and depressed the intensity of colloidal T4 ring were 90 and 1,131 ppb, respectively; other parameters were not affected (whole-body T4 was not determined at this time). At 12 weeks of exposure, LOECs for colloid depletion, hypertrophy, angiogenesis, and colloidal T4 ring were 11,480, 1,131, 90, and 11 ppb, respectively. All changes were reversible, but residual effects on angiogenesis and colloidal T4 ring intensity were still present after 12 weeks of recovery (LOEC, 11,480 ppb). Whole-body T 4 concentration, body growth (length and weight), and condition factor were not affected by perchlorate. The sensitivity and longevity of changes in colloidal T4 ring intensity and angiogenesis suggest their usefulness as novel markers of perchlorate exposure. The 12-week LOEC for colloidal T4 ring is the lowest reported for any perchlorate biomarker in aquatic vertebrates. ?? 2005 SETAC.

Effect of physical exertion on the biological monitoring of exposure to various solvents following exposure by inhalation in human volunteers: II. n-Hexane.

Science.gov (United States)

Tardif, Robert; Nadeau, Véronique; Truchon, Ginette; Brochu, Martin

2007-07-01

This study evaluated the impact of physical exertion on two n-hexane (HEX) exposure indicators in human volunteers exposed under controlled conditions in an inhalation chamber. A group of four volunteers (two women, two men) were exposed to HEX (50 ppm; 176 mg/m(3)) according to several scenarios involving several periods when volunteers performed either aerobic (AERO), muscular (MUSC), or both AERO/MUSC types of exercise. The target intensities for 30-min exercise periods separated by 15-min rest periods were the following: REST, 50W AERO [time-weighted average intensity including resting period (TWAI): 38W], 50W AERO/MUSC (TWAI: 34W), 100W AERO/MUSC (TWAI: 63W), and 100W AERO (TWAI: 71W) for 7 hr (two 3-hr exposure periods separated by 1 hr without exposure) and 50W MUSC for 3 hr (TWAI: 31W). Alveolar air and urine samples were collected at different time intervals before, during, and after exposure to measure unchanged HEX in expired air (HEX-A) and urinary 2,5-hexanedione (2,5-HD). HEX-A levels during exposures involving AERO activities (TWAI: 38W and 71W) were significantly enhanced (approximately +14%) compared with exposure at rest. MUSC or AERO/MUSC exercises were also associated with higher HEX-A levels but only at some sampling times. In contrast, end-of-exposure (7 hr) urinary 2,5-HD (mean +/- SD) was not modified by physical exertion: 4.14 +/- 1.51 micromol/L (REST), 4.02 +/- 1.52 micromol/L (TWAI 34W), 4.25 +/- 1.53 micromol/L (TWAI 38W), 3.73 +/- 2.09 micromol/L (TWAI 63W), 3.6 +/- 1.34 micromol/L (TWAI 71W) even though a downward trend was observed. Overall, this study showed that HEX kinetics is practically insensitive to moderate variations in workload intensity; only HEX-A levels increased slightly, and urinary 2,5-HD levels remained unchanged despite the fact that all types of physical exercise increased the pulmonary ventilation rate.

Repeated Exposure to Conditioned Fear Stress Increases Anxiety and Delays Sleep Recovery Following Exposure to an Acute Traumatic Stressor

OpenAIRE

Greenwood, Benjamin N.; Thompson, Robert S.; Opp, Mark R.; Fleshner, Monika

2014-01-01

Repeated stressor exposure can sensitize physiological responses to novel stressors and facilitate the development of stress-related psychiatric disorders including anxiety. Disruptions in diurnal rhythms of sleep–wake behavior accompany stress-related psychiatric disorders and could contribute to their development. Complex stressors that include fear-eliciting stimuli can be a component of repeated stress experienced by human beings, but whether exposure to repeated fear can prime the develo...

Post-test investigation result on the WWER-1000 fuel tested under severe accident conditions

International Nuclear Information System (INIS)

Goryachev, A.; Shtuckert, Yu.; Zwir, E.; Stupina, L.

1996-01-01

The model bundle of WWER-type were tested under SFD condition in the out-of-pile CORA installation. The objective of the test was to provide an information on the WWER-type fuel bundles behaviour under severe fuel damage accident conditions. Also it was assumed to compare the WWER-type bundle damage mechanisms with these experienced in the PWR-type bundle tests with aim to confirm a possibility to use the various code systems, worked our for PWR as applied to WWER. In order to ensure the possibility of the comparison of the calculated core degradation parameters with the real state of the tested bundle, some parameters have been measured on the bundle cross-sections under examination. Quantitative parameters of the bundle degradation have been evaluated by digital image processing of the bundle cross-sections. The obtained results are shown together with corresponding results obtained by the other participants of this investigation. (author). 3 refs, 13 figs

Laboratory algal bioassays using PAM fluorometry: effects of test conditions on the determination of herbicide and field sample toxicity.

Science.gov (United States)

Sjollema, Sascha B; van Beusekom, Sebastiaan A M; van der Geest, Harm G; Booij, Petra; de Zwart, Dick; Vethaak, A Dick; Admiraal, Wim

2014-05-01

Pulse Amplitude Modulation (PAM) fluorometry, based on chlorophyll a fluorescence, is a frequently used technique in algal bioassays to assess toxicity of single compounds or complex field samples. Several test conditions can influence the test results, and because a standardized test protocol is currently lacking, linking the results of different studies is difficult. Therefore, the aim of the present study was to gain insight into the effects of test conditions of laboratory algal bioassays using PAM fluorometry on the outcome of toxicity tests. To this purpose, we described the results from several pilot studies on test development in which information is provided on the effects of the main test factors during the pretest phase, the test preparation, the exposure period, and the actual measurement. The experiments were focused on individual herbicides and complex field samples and included the effects of culturing conditions, cell density, solvent concentration, exposure time, and the presence of actinic light. Several of these test conditions were found to influence the outcome of the toxicity test, and the presented information provides important background information for the interpretation of toxicity results and describes which test conditions should be taken into account when using an algal bioassay with PAM fluorometry. Finally, the application of PAM fluorometry in algal toxicity testing is discussed. © 2014 SETAC.

Effect of physical exertion on the biological monitoring of exposure of various solvents following exposure by inhalation in human volunteers: I. Toluene.

Science.gov (United States)

Nadeau, Véronique; Truchon, Ginette; Brochu, Martin; Tardif, Robert

2006-09-01

Physical exertion (work load) has been recognized as one of several factors that can influence the kinetics of xenobiotics within the human body. This study was undertaken to evaluate the impact of physical exertion on two exposure indicators of toluene (TOL) in human volunteers exposed under controlled conditions in an inhalation chamber. A group of four volunteers (one woman, three men) were exposed to TOL (50 ppm) according to the following scenarios involving several periods during which volunteers were asked to perform either aerobic (AERO), muscular (MUSC), or both (AERO/MUSC) types of physical exercise (exercise bicycle, treadmills, pulleys). The target intensities (W) for each exercising period of 30 min--interspaced with 15 min at rest--were the following: REST, 50 W AERO (time-weighted average intensity [TWAI]: 46 watts); 50 W AERO/MUSC (TWAI: 38 watts) and 100 W AERO (TWAI: 71 watts) for 7 hours and 50 W MUSC for 3 hours (TWAI: 29 watts). Alveolar air and urine samples were collected at different time intervals before, during, and after exposure for the measurement of unchanged TOL in expired air (TOL-A) and urinary o-cresol (o-CR). Overall, the results showed that TOL-A measured during and after all scenarios involving physical activities were higher (approximately 1.4-2.0 fold) compared with exposures at rest. All scenarios involving physical exertion also resulted in increased end-of-exposure urinary o-CR (mean +/- SD): 0.9 +/- 0.1 mg/L (REST) vs. 2.0 +/- 0.1 mg/L (TWAI 46 watts). However, exposure at a TWAI of 71 watts did not further increase o-CR excretion (1.7 +/- 0.2 mg/L). This study confirms the significant effect of work load on TOL kinetics and showed that o-CR excretion increased proportionally with work load expressed as TWAI or with the estimated mean pulmonary ventilation during the period of exposure. This study also shows that exposure to TOL (50 ppm) involving a work load of around 50 W (light intensity) or lower is likely to produce

Hydrogen generation, distribution and combustion under severe LWR accident conditions: a state-of-technology report

International Nuclear Information System (INIS)

Postma, A.K.; Hilliard, R.K.

1983-03-01

This report reviews the current state of technology regarding hydrogen safety issues in light water reactor plants. Topics considered in this report include hydrogen generation, distribution in containment, and combustion characteristics. A companion report addresses hydrogen control. The objectives of the study were to identify the key safety issues related to hydrogen produced under severe accident conditions, to describe the state of technology for each issue, and to point out ongoing programs aimed at resolving the open issues

Comparative effects of pulmonary and parenteral Δ⁹-tetrahydrocannabinol exposure on extinction of opiate-induced conditioned aversion in rats.

Science.gov (United States)

Manwell, Laurie A; Mallet, Paul E

2015-05-01

Evidence suggesting that the endogenous cannabinoid (eCB) system can be manipulated to facilitate or impair extinction of learned behaviours has important consequences for opiate withdrawal and abstinence. We demonstrated that the fatty acid amide hydrolase (FAAH) inhibitor URB597, which increases eCB levels, facilitates extinction of a naloxone-precipitated morphine withdrawal-induced conditioned place aversion (CPA). The potential of the exogenous CB1 ligand, Δ(9)-tetrahydrocannabinol (Δ(9)-THC), to facilitate extinction of this CPA was tested. Effects of both pulmonary and parenteral Δ(9)-THC exposure were evaluated using comparable doses previously determined. Rats trained to associate a naloxone-precipitated morphine withdrawal with a floor cue were administered Δ(9)-THC-pulmonary (1, 5, 10 mg vapour inhalation) or parenteral (0.5, 1.0, 1.5 mg/kg intraperitoneal injection)-prior to each of 20 to 28 extinction/testing trials. Vapourized Δ(9)-THC facilitated extinction of the CPA in a dose- and time-dependent manner: 5 and 10 mg facilitated extinction compared to vehicle and 1 mg Δ(9)-THC. Injected Δ(9)-THC significantly impaired extinction only for the 1.0-mg/kg dose: it prolonged the CPA fourfold longer than the vehicle and 0.5- and 1.5-mg/kg doses. These data suggest that both dose and route of Δ(9)-THC administration have important consequences for its pharmacokinetic and behavioural effects; specifically, pulmonary exposure at higher doses facilitates, whereas pulmonary and parenteral exposure at lower doses impairs, rates of extinction learning for CPA. Pulmonary-administered Δ(9)-THC may prove beneficial for potentiation of extinction learning for aversive memories, such as those supporting drug-craving/seeking in opiate withdrawal syndrome, and other causes of conditioned aversions, such as illness and stress.

Silica exposure and silicosis among Ontario hardrock miners: II. Exposure estimates.

Science.gov (United States)

Verma, D K; Sebestyen, A; Julian, J A; Muir, D C; Schmidt, H; Bernholz, C D; Shannon, H S

1989-01-01

An epidemiological investigation was carried out to determine the relationship between silicosis in hardrock miners in Ontario and cumulative exposure to silica (free crystalline silica--alpha quartz) dust. This second report describes a side-by-side air-sampling program used to derive a konimeter/gravimetric silica conversion curve. A total of 2,360 filter samples and 90,000 konimeter samples were taken over 2 years in two mines representing the ore types gold and uranium, both in existing conditions as well as in an experimental stope in which dry drilling was used to simulate the high dust conditions of the past. The method of calculating cumulative respirable silica exposure indices for each miner is reported.

Considering human exposure to pesticides in food products: Importance of dissipation dynamics

DEFF Research Database (Denmark)

Fantke, Peter; Juraske, Ronnie; Jolliet, Olivier

2014-01-01

The general public is continuously concerned about effects from pesticide exposure via residues in food crops. However, impacts from pesticide exposure are mostly neglected in food product-related LCAs. Time-to-harvest and dissipation from crops mainly drive residue dynamics with dissipation...... as most uncertain aspect in characterization modeling. We analyzed measured half-lives (n=4513) with 95% falling between 0.6 and 29 days. With ~500 pesticides authorized alone in the EU for several hundred crops, however, experimental stud-ies only cover few possible pesticide-crop combinations. Therefore......, we estimated dissipation from measured data and provide reference half-lives for 333 pesticides applied at 20°C under field conditions. Our framework allows for detailed explorations of dietary choices in LCA with respect to human health impacts from pesticide exposure via crop consumption. The next...

Understanding the Impact of Exposure Patterns on Risks from Combined Exposures to Multiple Chemicals

Science.gov (United States)

The talk was invited so there is no formal abstract. However, the focus of the talk is on the use of exposure information in the evaluation of risks from combined exposures to chemicals. The talk presents a bit of history and several case studies. All empirical data presented hav...

Long-term food-exposure of zebrafish to PCB mixtures mimicking some environmental situations induces ovary pathology and impairs reproduction ability.

Science.gov (United States)

Daouk, Tarek; Larcher, Thibaut; Roupsard, François; Lyphout, Laura; Rigaud, Cyril; Ledevin, Mireille; Loizeau, Véronique; Cousin, Xavier

2011-10-01

Although the use of polychlorinated biphenyls (PCBs) has been banned for several decades, they are still present in the environment and are occasionally mechanically released from sediment or transferred through the trophic chain. Field analyses have established correlations between exposure to PCBs and alterations in fish physiology including reproductive function. Experimental exposures have been mainly performed using dioxin-like PCBs or other congeners at very high concentrations. However, these studies are often difficult to relate to real-life conditions. In the present study, we performed a life-cycle exposure using zebrafish model and mixtures representative of some environmental situations in terms of doses, composition and containing mainly non dioxin-like congeners. Exposure was performed through diet which is the main contamination route in the field. We demonstrated a bioaccumulation of PCBs in males and females as well as a maternal transfer to the eggs. Survival, growth and organ size were similar for all conditions. Several reproductive traits were altered after exposure to a PCB-contaminated diet, including a reduction in the number of fertilized eggs per spawn as well as an increase of the number of poorly fertilized spawns. This latter observation was found irrespective of the sex of contaminated fish. This is related to modifications of ovary histology revealing a decrease of maturing follicles and an increase of atretic follicles in the ovaries of females exposed to PCBs. These results indicate that exposure to PCBs mixtures mimicking some environmental situations, including mainly non dioxin-like congeners, can lead to a dramatic reduction in the number of offspring produced by a female over a lifetime. This is of great concern for wild species living under natural conditions. Copyright © 2011 Elsevier B.V. All rights reserved.

Anticoagulant rodenticide toxicity to non-target wildlife under controlled exposure conditions

Science.gov (United States)

Rattner, Barnett A.; Mastrota, F. Nicholas; van den Brink, Nico; Elliott, J.; Shore, R.; Rattner, B.

2018-01-01

Much of our understanding of anticoagulant rodenticide toxicity to non-target wildlife has been derived from molecular through whole animal research and registration studies in domesticated birds and mammals, and to a lesser degree from trials with captive wildlife. Using these data, an adverse outcome pathway identifying molecular initiating and anchoring events (inhibition of vitamin K epoxide reductase, failure to activate clotting factors), and established and plausible linkages (coagulopathy, hemorrhage, anemia, reduced fitness) associated with toxicity, is presented. Controlled exposure studies have demonstrated that second-generation anticoagulant rodenticides (e.g., brodifacoum) are more toxic than first- and intermediate-generation compounds (e.g., warfarin, diphacinone), however the difference in potency is diminished when first- and intermediate-generation compounds are administered on multiple days. Differences in species sensitivity are inconsistent among compounds. Numerous studies have compared mortality rate of predators fed prey or tissue containing anticoagulant rodenticides. In secondary exposure studies in birds, brodifacoum appears to pose the greatest risk, with bromadiolone, difenacoum, flocoumafen and difethialone being less hazardous than brodifacoum, and warfarin, coumatetralyl, coumafuryl, chlorophacinone and diphacinone being even less hazardous. In contrast, substantial mortality was noted in secondary exposure studies in mammals ingesting prey or tissue diets containing either second- or intermediate-generation compounds. Sublethal responses (e.g., prolonged clotting time, reduced hematocrit and anemia) have been used to study the sequelae of anticoagulant intoxication, and to some degree in the establishment of toxicity thresholds or toxicity reference values. Surprisingly few studies have undertaken histopathological evaluations to identify cellular lesions and hemorrhage associated with anticoagulant rodenticide exposure in non

Climate Change and Crop Exposure to Adverse Weather: Changes to Frost Risk and Grapevine Flowering Conditions.

Science.gov (United States)

Mosedale, Jonathan R; Wilson, Robert J; Maclean, Ilya M D

2015-01-01

The cultivation of grapevines in the UK and many other cool climate regions is expected to benefit from the higher growing season temperatures predicted under future climate scenarios. Yet the effects of climate change on the risk of adverse weather conditions or events at key stages of crop development are not always captured by aggregated measures of seasonal or yearly climates, or by downscaling techniques that assume climate variability will remain unchanged under future scenarios. Using fine resolution projections of future climate scenarios for south-west England and grapevine phenology models we explore how risks to cool-climate vineyard harvests vary under future climate conditions. Results indicate that the risk of adverse conditions during flowering declines under all future climate scenarios. In contrast, the risk of late spring frosts increases under many future climate projections due to advancement in the timing of budbreak. Estimates of frost risk, however, were highly sensitive to the choice of phenology model, and future frost exposure declined when budbreak was calculated using models that included a winter chill requirement for dormancy break. The lack of robust phenological models is a major source of uncertainty concerning the impacts of future climate change on the development of cool-climate viticulture in historically marginal climatic regions.

TYPHOID FEVER WITH FATAL OUTCOME IN PEOPLE WITH SEVERE TROPHOLOGICAL FAILURE IN EXTREME CONDITIONS

Directory of Open Access Journals (Sweden)

Yu. I. Lyashenko

2017-01-01

Full Text Available For purpose of clinical and morphological characterization of typhoid fever with fatal outcome was perform analysis of medical documentation as well as postmortem studies of internal tissues in 36men aged 21 to 34 years with severe body weight loss and in the conditions of combat stress in period from 1983 to 1985. The results of the study find a number of clinical and pathomorphological features of typhoid fever in patients with body weight deficiency that were in extreme conditions. Focal changes of the central nervous system were detected. The defeat of the respiratory system was characterized from the first days of the disease by bronchitis, and in the subsequent development of pneumonia, plevritis and empyema of the pleura. Majority of patients had symptoms of cardiovascular and renal failure. In died in the first week of the disease and in 2/3 parts – in a later period were combined with the symptoms of infectious-toxic encephalopathy and severe acute respiratory failure. All died had postmortem dystrophic changes of cardiomyocytes, and in patients had fatal outcome in 2–5 weeks – also focal or diffuse myocarditis. In a third of the patients who died, the disease was complicated by intestinal perforations. In a number of cases, peritonitis was a consequence of necrosis of mesenteric lymph nodes. In all patients with a fatal outcome, hemorrhagic (thrombohemorrhagic syndrome was diagnosed. A significant proportion of patients posthumously detected signs of sepsis and other complications, many of which could be the cause of death.

Human exposure to bisphenol A by biomonitoring: Methods, results and assessment of environmental exposures

International Nuclear Information System (INIS)

Dekant, Wolfgang; Voelkel, Wolfgang

2008-01-01

Human exposure to bisphenol A is controversially discussed. This review critically assesses methods for biomonitoring of bisphenol A exposures and reported concentrations of bisphenol A in blood and urine of non-occupationally ('environmentally') exposed humans. From the many methods published to assess bisphenol A concentrations in biological media, mass spectrometry-based methods are considered most appropriate due to high sensitivity, selectivity and precision. In human blood, based on the known toxicokinetics of bisphenol A in humans, the expected very low concentrations of bisphenol A due to rapid biotransformation and the very rapid excretion result in severe limitations in the use of reported blood levels of bisphenol A for exposure assessment. Due to the rapid and complete excretion of orally administered bisphenol A, urine samples are considered as the appropriate body fluid for bisphenol A exposure assessment. In urine samples from several cohorts, bisphenol A (as glucuronide) was present in average concentrations in the range of 1-3 μg/L suggesting that daily human exposure to bisphenol A is below 6 μg per person (< 0.1 μg/kg bw/day) for the majority of the population

Radiation protection programme for existing exposure situation

International Nuclear Information System (INIS)

Ramadhani, Hilali Hussein

2016-04-01

This study was conducted to develop the Radiation protection Programme (RPP) to ensure that measures are in place for protection of individuals from the existing source of exposure. The study established a number of protective and remedial actions to be considered by the responsible regulatory Authority, licensee for existing exposure in workplace and dwellings. Tanzania is endowed with a number NORMs processing industries with an experience of uncontrolled exploration and extraction of minerals and the use of unsafe mining methods leading to severe environmental damage and appalling living conditions in the mining communities. Some of NORMs industries have been abandoned due to lack of an effect management infrastructure. The residual radioactive materials have been found to be the most import source of existing exposure resulted from NORMs industries. The Radon gas and its progeny have also been found to be a source of existing exposure from natural source as well as the major source of risk and health effects associated with existing exposure situation. The following measures have been discovered to play a pivotal role in avoiding or reducing the source of exposure to individuals such as restriction of the use of the construction materials, restriction on the consumption of foodstuffs and restriction on the access to the land and buildings, the removal of the magnitude of the source in terms of activity concentration as well as improvement of ventilation in dwellings. Therefore, the regulatory body (Tanzania Atomic Energy Commission) should examine the major areas outlined in the established RRP for existing exposure situation resulted from the NORMs industries and natural sources so as to develop strategies that will ensure the adequate protection of members of the public and the environment as well as guiding operating organizations to develop radiation protection and safety measures for workers. (au)

Effects of Cannabinoid Exposure during Adolescence on the Conditioned Rewarding Effects of WIN 55212-2 and Cocaine in Mice: Influence of the Novelty-Seeking Trait

Directory of Open Access Journals (Sweden)

M. Rodríguez-Arias

2016-01-01

Full Text Available Adolescent exposure to cannabinoids enhances the behavioural effects of cocaine, and high novelty-seeking trait predicts greater sensitivity to the conditioned place preference (CPP induced by this drug. Our aim was to evaluate the influence of novelty-seeking on the effects of adolescent cannabinoid exposure. Adolescent male mice were classified as high or low novelty seekers (HNS and LNS in the hole-board test. First, we evaluated the CPP induced by the cannabinoid agonist WIN 55212-2 (0.05 and 0.075 mg/kg, i.p. in HNS and LNS mice. Then, HNS and LNS mice were pretreated i.p. with vehicle, WIN 55212-2 (0.1 mg/kg, or cannabinoid antagonist rimonabant (1 mg/kg and were subsequently conditioned with WIN 55212-2 (0.05 mg/kg, i.p. or cocaine (1 or 6 mg/kg, i.p.. Only HNS mice conditioned with the 0.075 mg/kg dose acquired CPP with WIN 55212-2. Adolescent exposure to this cannabinoid agonist increased the rewarding effects of 1 mg/kg of cocaine in both HNS and LNS mice, and in HNS mice it also increased the reinstating effect of a low dose of cocaine. Our results endorse a role for individual differences such as a higher propensity for sensation-seeking in the development of addiction.

Establishment of Technical Collaboration basis between Korea and France for the development of severe accident assessment computer code under high burnup condition

International Nuclear Information System (INIS)

Kim, H. D.; Kim, D. H.; Park, S. Y.; Park, J. H.

2005-10-01

This project was performed by KAERI in the frame of construction of the international cooperative basis on the nuclear energy. This was supported from MOST under the title of 'Establishment of Technical Collaboration basis between Korea and France for the development of severe accident assessment computer code under high burn up condition'. The current operating NPP are converting the burned fuel to the wasted fuel after burn up of 40 GWD/MTU. But in Korea, burn up of more than 60 GWD/MTU will be expected because of the high fuel efficiency but also cost saving for storing the wasted fuel safely. The domestic research for the purpose of developing the fuel and the cladding that can be used under the high burn up condition up to 100 GWD/MTU is in progress now. But the current computer code adopts the model and the data that are valid only up to the 40 GWD/MTU at most. Therefore the current model could not take into account the phenomena that may cause differences in the fission product release behavior or in the core damage process due to the high burn up operation (more than 40 GWD/MTU). To evaluate the safety of the NPP with the high burn up fuel, the improvement of current severe accident code against the high burn up condition is an important research item. Also it should start without any delay. Therefore, in this study, an expert group was constructed to establish the research basis for the severe accident under high burn up conditions. From this expert group, the research items regarding the high burn up condition were selected and identified through discussion and technical seminars. Based on these selected items, the meeting between IRSN and KAERI to find out the cooperative research items on the severe accident under the high burn up condition was held in the IRSN headquater in Paris. After the meeting, KAERI and IRSN agreed to cooperate with each other on the selected items, and to co-host the international seminar, and to develop the model and to

Toxicity assessment of TiO{sub 2} nanoparticles in zebrafish embryos under different exposure conditions

Energy Technology Data Exchange (ETDEWEB)

Clemente, Z., E-mail: zairaclemente@yahoo.com.br [Laboratório de Ecotoxicologia e Biossegurança, Embrapa CNPMA, Jaguariúna, SP (Brazil); Programa de Pós-graduação em Biologia Funcional e Molecular, UNICAMP, Campinas, SP (Brazil); Castro, V.L.S.S. [Laboratório de Ecotoxicologia e Biossegurança, Embrapa CNPMA, Jaguariúna, SP (Brazil); Moura, M.A.M. [Laboratório da Ciência das Plantas Daninhas, Instituto Biológico, APTA/SAA, Campinas, SP (Brazil); Jonsson, C.M. [Laboratório de Ecotoxicologia e Biossegurança, Embrapa CNPMA, Jaguariúna, SP (Brazil); Fraceto, L.F. [Programa de Pós-graduação em Biologia Funcional e Molecular, UNICAMP, Campinas, SP (Brazil); Departamento de Engenharia Ambiental, UNESP, Sorocaba, SP (Brazil)

2014-02-15

Highlights: •Nano-TiO{sub 2} accelerated hatching of the larvae. •Exposure to anatase/rutile mixture under UV light altered the equilibrium and survival of the larvae. •Nano-TiO{sub 2} caused alterations in the activities of CAT and GST. -- Abstract: The popularity of TiO{sub 2} nanoparticles (nano-TiO{sub 2}) lies in their wide range of nanotechnological applications, together with low toxicity. Meanwhile, recent studies have shown that the photocatalytic properties of this material can result in alterations in their behavior in the environment, causing effects that have not yet been fully elucidated. The objective of this study was to evaluate the toxicity of two formulations of nano-TiO{sub 2} under different illumination conditions, using an experimental model coherent with the principle of the three Rs of alternative animal experimentation (reduction, refinement, and replacement). Embryos of the fish Danio rerio were exposed for 96 h to different concentrations of nano-TiO{sub 2} in the form of anatase (TA) or an anatase/rutile mixture (TM), under either visible light or a combination of visible and ultraviolet light (UV). The acute toxicity and sublethal parameters evaluated included survival rates, malformation, hatching, equilibrium, and overall length of the larvae, together with biochemical biomarkers (specific activities of catalase (CAT), glutathione S-transferase (GST), and acid phosphatase (AP)). Both TA and TM caused accelerated hatching of the larvae. Under UV irradiation, there was greater mortality of the larvae of the groups exposed to TM, compared to those exposed to TA. Exposure to TM under UV irradiation altered the equilibrium of the larvae. Alterations in the activities of CAT and GST were indicative of oxidative stress, although no clear dose-response relationship was observed. The effects of nano-TiO{sub 2} appeared to depend on both the type of formulation and the illumination condition. The findings contribute to elucidation of the

Non-smoker exposure to secondhand cannabis smoke II: Effect of room ventilation on the physiological, subjective, and behavioral/cognitive effects.

Science.gov (United States)

Herrmann, Evan S; Cone, Edward J; Mitchell, John M; Bigelow, George E; LoDico, Charles; Flegel, Ron; Vandrey, Ryan

2015-06-01

Cannabis is the most widely used illicit drug. Many individuals are incidentally exposed to secondhand cannabis smoke, but little is known about the effects of this exposure. This report examines the physiological, subjective, and behavioral/cognitive effects of secondhand cannabis exposure, and the influence of room ventilation on these effects. Non-cannabis-using individuals were exposed to secondhand cannabis smoke from six individuals smoking cannabis (11.3% THC) ad libitum in a specially constructed chamber for 1h. Chamber ventilation was experimentally manipulated so that participants were exposed under unventilated conditions or with ventilation at a rate of 11 air exchanges/h. Physiological, subjective and behavioral/cognitive measures of cannabis exposure assessed after exposure sessions were compared to baseline measures. Exposure to secondhand cannabis smoke under unventilated conditions produced detectable cannabinoid levels in blood and urine, minor increases in heart rate, mild to moderate self-reported sedative drug effects, and impaired performance on the digit symbol substitution task (DSST). One urine specimen tested positive at using a 50 ng/ml cut-off and several specimens were positive at 20 ng/ml. Exposure under ventilated conditions resulted in much lower blood cannabinoid levels, and did not produce sedative drug effects, impairments in performance, or positive urine screen results. Room ventilation has a pronounced effect on exposure to secondhand cannabis smoke. Under extreme, unventilated conditions, secondhand cannabis smoke exposure can produce detectable levels of THC in blood and urine, minor physiological and subjective drug effects, and minor impairment on a task requiring psychomotor ability and working memory. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Total lymphoid irradiation based conditioning for hematopoietic stem cell transplantation in severe aplastic anemia

International Nuclear Information System (INIS)

Lee, Yun Hee; Kim, Ji Yoon; Choi, Byung Ock; Ryu, Mi Ryeong; Chung, Su Mi

2012-01-01

To retrospectively evaluate the outcome and toxicity of total lymphoid irradiation (TLI) based conditioning regimen for allogeneic hematopoietic stem cell transplantation (HSCT) in severe aplastic anemia (SAA) patients who experienced an engraftment failure from prior HSCT or were heavily transfused. Between 1995 and 2006, 20 SAA patients received TLI for conditioning of HSCT. All patients were multi-transfused or had long duration of disease. Fifteen (75%) patients had graft failure from prior HSCT. In 18 (90%) patients, the donors were human leukocyte antigen identical siblings. The stem cell source was the peripheral blood stem cell in 15 (75%) patients. The conditioning regimen was composed of antithymocyte globulin plus TLI with a median dose of 750 cGy in 1 fraction. The graft-versus-host disease (GVHD) prophylaxis used cyclosporine with methotrexate. With a median follow-up of 10.8 years, graft failures developed in 6 patients. Among them, 3 patients received their third HSCT to be engrafted finally. The Kaplan-Meier overall survival rate was 85.0% and 83.1% at 5 and 10 years, respectively. The incidence of acute and chronic GVHD was 20% and 20%, respectively. None of the patients have developed a malignancy after HSCT. In our study, TLI based conditioning in allogeneic HSCT was feasible with acceptable rates of GVHD in SAA patients who experienced graft failure from prior HSCT or was at a high risk of graft rejection. We achieved relatively better results of engraftment and survival with a long term follow-up.

Total lymphoid irradiation based conditioning for hematopoietic stem cell transplantation in severe aplastic anemia

Energy Technology Data Exchange (ETDEWEB)

Lee, Yun Hee; Kim, Ji Yoon; Choi, Byung Ock; Ryu, Mi Ryeong; Chung, Su Mi [Dept. of Radiation Oncology, The Catholic University of Korea College of Medicine, Seoul (Korea, Republic of)

2012-12-15

To retrospectively evaluate the outcome and toxicity of total lymphoid irradiation (TLI) based conditioning regimen for allogeneic hematopoietic stem cell transplantation (HSCT) in severe aplastic anemia (SAA) patients who experienced an engraftment failure from prior HSCT or were heavily transfused. Between 1995 and 2006, 20 SAA patients received TLI for conditioning of HSCT. All patients were multi-transfused or had long duration of disease. Fifteen (75%) patients had graft failure from prior HSCT. In 18 (90%) patients, the donors were human leukocyte antigen identical siblings. The stem cell source was the peripheral blood stem cell in 15 (75%) patients. The conditioning regimen was composed of antithymocyte globulin plus TLI with a median dose of 750 cGy in 1 fraction. The graft-versus-host disease (GVHD) prophylaxis used cyclosporine with methotrexate. With a median follow-up of 10.8 years, graft failures developed in 6 patients. Among them, 3 patients received their third HSCT to be engrafted finally. The Kaplan-Meier overall survival rate was 85.0% and 83.1% at 5 and 10 years, respectively. The incidence of acute and chronic GVHD was 20% and 20%, respectively. None of the patients have developed a malignancy after HSCT. In our study, TLI based conditioning in allogeneic HSCT was feasible with acceptable rates of GVHD in SAA patients who experienced graft failure from prior HSCT or was at a high risk of graft rejection. We achieved relatively better results of engraftment and survival with a long term follow-up.

Numerical module for debris behavior under severe accident conditions

International Nuclear Information System (INIS)

Kisselev, A.E.; Kobelev, G.V.; Strizhov, V.F.; Vasiliev, A.D.

2005-01-01

The late phase of a hypothetical severe accident in a nuclear reactor is characterized by the appearance of porous debris and liquid pools in core region and lower head of the reactor vessel. Thermal hydraulics and heat transfer in these regions are very important for adequate analysis of severe accident dynamics. The purpose of this work is to develop a universal module which is able to model above-mentioned phenomena on the basis of modern physical concepts. The original approach for debris evolution is developed from classical principles using a set of parameters including debris porosity; average particle diameter; temperatures and mass fractions of solid, liquid and gas phases; specific interface areas between different phases; effective thermal conductivity of each phase, including radiative heat conductivity; mass and energy fluxes through the interfaces. The calculation results of several tests on modeling of porous debris behavior, including the MP-1 experiment, are presented in comparison with experimental data. The results are obtained using this module implemented into the Russian best estimate code, RATEG/SVECHA/HEFEST, which was developed for modeling severe accident thermal hydraulics and late phase phenomena in VVER nuclear power plants. (author)

Public health impacts of the severe haze in Equatorial Asia in September-October 2015: demonstration of a new framework for informing fire management strategies to reduce downwind smoke exposure

Science.gov (United States)

Koplitz, Shannon N.; Mickley, Loretta J.; Marlier, Miriam E.; Buonocore, Jonathan J.; Kim, Patrick S.; Liu, Tianjia; Sulprizio, Melissa P.; DeFries, Ruth S.; Jacob, Daniel J.; Schwartz, Joel; Pongsiri, Montira; Myers, Samuel S.

2016-09-01

In September-October 2015, El Niño and positive Indian Ocean Dipole conditions set the stage for massive fires in Sumatra and Kalimantan (Indonesian Borneo), leading to persistently hazardous levels of smoke pollution across much of Equatorial Asia. Here we quantify the emission sources and health impacts of this haze episode and compare the sources and impacts to an event of similar magnitude occurring under similar meteorological conditions in September-October 2006. Using the adjoint of the GEOS-Chem chemical transport model, we first calculate the influence of potential fire emissions across the domain on smoke concentrations in three receptor areas downwind—Indonesia, Malaysia, and Singapore—during the 2006 event. This step maps the sensitivity of each receptor to fire emissions in each grid cell upwind. We then combine these sensitivities with 2006 and 2015 fire emission inventories from the Global Fire Assimilation System (GFAS) to estimate the resulting population-weighted smoke exposure. This method, which assumes similar smoke transport pathways in 2006 and 2015, allows near real-time assessment of smoke pollution exposure, and therefore the consequent morbidity and premature mortality, due to severe haze. Our approach also provides rapid assessment of the relative contribution of fire emissions generated in a specific province to smoke-related health impacts in the receptor areas. We estimate that haze in 2015 resulted in 100 300 excess deaths across Indonesia, Malaysia and Singapore, more than double those of the 2006 event, with much of the increase due to fires in Indonesia’s South Sumatra Province. The model framework we introduce in this study can rapidly identify those areas where land use management to reduce and/or avoid fires would yield the greatest benefit to human health, both nationally and regionally.

Widespread exposure to lead affects the body condition of free-living whooper swans Cygnus cygnus wintering in Britain.

Science.gov (United States)

Newth, J L; Rees, E C; Cromie, R L; McDonald, R A; Bearhop, S; Pain, D J; Norton, G J; Deacon, C; Hilton, G M

2016-02-01

Lead poisoning, through the ingestion of spent lead gunshot, is an established cause of morbidity and mortality in waterbirds globally, but the thresholds at which blood levels begin to affect the physiology of birds in the wild are less well known. Here we determine the prevalence of lead exposure in whooper swans and, for the first time, identify the level of blood lead associated with initial reductions in body condition. Blood lead elevated above background levels (i.e. >20 μg dL(-1)) was found in 41.7% (125/300) of swans tested. Blood lead was significantly negatively associated with winter body condition when levels were ≥44 μg dL(-1) (27/260 = 10%). Our findings indicating that sub-lethal impacts of lead on body condition occur at the lower end of previously established clinical thresholds and that a relatively high proportion of individuals in this population may be affected, reaffirm the importance of reducing contamination of the environment with lead shot. Copyright © 2015 Elsevier Ltd. All rights reserved.

Exposure to nature counteracts aggression after depletion.

Science.gov (United States)

Wang, Yan; She, Yihan; Colarelli, Stephen M; Fang, Yuan; Meng, Hui; Chen, Qiuju; Zhang, Xin; Zhu, Hongwei

2018-01-01

Acts of self-control are more likely to fail after previous exertion of self-control, known as the ego depletion effect. Research has shown that depleted participants behave more aggressively than non-depleted participants, especially after being provoked. Although exposure to nature (e.g., a walk in the park) has been predicted to replenish resources common to executive functioning and self-control, the extent to which exposure to nature may counteract the depletion effect on aggression has yet to be determined. The present study investigated the effects of exposure to nature on aggression following depletion. Aggression was measured by the intensity of noise blasts participants delivered to an ostensible opponent in a competition reaction-time task. As predicted, an interaction occurred between depletion and environmental manipulations for provoked aggression. Specifically, depleted participants behaved more aggressively in response to provocation than non-depleted participants in the urban condition. However, provoked aggression did not differ between depleted and non-depleted participants in the natural condition. Moreover, within the depletion condition, participants in the natural condition had lower levels of provoked aggression than participants in the urban condition. This study suggests that a brief period of nature exposure may restore self-control and help depleted people regain control over aggressive urges. © 2017 Wiley Periodicals, Inc.

Exposure is not enough: suppressing stimuli from awareness can abolish the mere exposure effect.

Directory of Open Access Journals (Sweden)

Daniel de Zilva

Full Text Available Passive exposure to neutral stimuli increases subsequent liking of those stimuli--the mere exposure effect. Because of the broad implications for understanding and controlling human preferences, the role of conscious awareness in mere exposure has received much attention. Previous studies have claimed that the mere exposure effect can occur without conscious awareness of the stimuli. In two experiments, we applied a technique new to the mere exposure literature, called continuous flash suppression, to expose stimuli for a controlled duration with and without awareness. To ensure the reliability of the awareness manipulation, awareness was monitored on a trial-by-trial basis. Our results show that under these conditions the mere exposure effect does not occur without conscious awareness. In contrast, only when participants were aware of the stimuli did exposure increase liking and recognition. Together these data are consistent with the idea that the mere exposure effect requires conscious awareness and has important implications for theories of memory and affect.

Exposure is not enough: suppressing stimuli from awareness can abolish the mere exposure effect.

Science.gov (United States)

de Zilva, Daniel; Vu, Luke; Newell, Ben R; Pearson, Joel

2013-01-01

Passive exposure to neutral stimuli increases subsequent liking of those stimuli--the mere exposure effect. Because of the broad implications for understanding and controlling human preferences, the role of conscious awareness in mere exposure has received much attention. Previous studies have claimed that the mere exposure effect can occur without conscious awareness of the stimuli. In two experiments, we applied a technique new to the mere exposure literature, called continuous flash suppression, to expose stimuli for a controlled duration with and without awareness. To ensure the reliability of the awareness manipulation, awareness was monitored on a trial-by-trial basis. Our results show that under these conditions the mere exposure effect does not occur without conscious awareness. In contrast, only when participants were aware of the stimuli did exposure increase liking and recognition. Together these data are consistent with the idea that the mere exposure effect requires conscious awareness and has important implications for theories of memory and affect.

Analysis of flammability in the attached buildings to containment under severe accident conditions

Energy Technology Data Exchange (ETDEWEB)

Rosa, J.C. de la, E-mail: juan-carlos.de-la-rosa-blul@ec.europa.eu [European Commission Joint Research Centre (Netherlands); Fornós, Joan, E-mail: jfornosh@anacnv.com [Asociación Nuclear Ascó-Vandellós (Spain)

2016-11-15

Highlights: • Analysis of flammability conditions in buildings outside containment. • Stepwise approach easily applicable for any kind of containment and attached buildings layout. • Detailed application for real plant conditions has been included. - Abstract: Right after the events unfolded in Fukushima Daiichi, the European Union countries agreed in subjecting Nuclear Power Plants to Stress Tests as developed by WENRA and ENSREG organizations. One of the results as implemented in many European countries derived from such tests consisted of mandatory technical instructions issued by nuclear regulatory bodies on the analysis of potential risk of flammable gases in attached buildings to containment. The current study addresses the key aspects of the analysis of flammable gases leaking to auxiliary buildings attached to Westinghouse large-dry PWR containment for the specific situation where mitigating systems to prevent flammable gases to grow up inside containment are available, and containment integrity is preserved – hence avoiding isolation system failure. It also provides a full practical exercise where lessons learned derived from the current study – hence limited to the imposed boundary conditions – are applied. The leakage of gas from the containment to the support buildings is based on separate calculations using the EPRI-owned Modular Accident Analysis Program, MAAP4.07. The FATE™ code (facility Flow, Aerosol, Thermal, and Explosion) was used to model the transport and distribution of leaked flammable gas (H{sub 2} and CO) in the penetration buildings. FATE models the significant mixing (dilution) which occurs as the released buoyant gas rises and entrains air. Also, FATE accounts for the condensation of steam on room surfaces, an effect which acts to concentrate flammable gas. The results of the analysis show that during a severe accident, flammable conditions are unlikely to occur in compartmentalized buildings such as the one used in the

Analysis of flammability in the attached buildings to containment under severe accident conditions

International Nuclear Information System (INIS)

Rosa, J.C. de la; Fornós, Joan

2016-01-01

Highlights: • Analysis of flammability conditions in buildings outside containment. • Stepwise approach easily applicable for any kind of containment and attached buildings layout. • Detailed application for real plant conditions has been included. - Abstract: Right after the events unfolded in Fukushima Daiichi, the European Union countries agreed in subjecting Nuclear Power Plants to Stress Tests as developed by WENRA and ENSREG organizations. One of the results as implemented in many European countries derived from such tests consisted of mandatory technical instructions issued by nuclear regulatory bodies on the analysis of potential risk of flammable gases in attached buildings to containment. The current study addresses the key aspects of the analysis of flammable gases leaking to auxiliary buildings attached to Westinghouse large-dry PWR containment for the specific situation where mitigating systems to prevent flammable gases to grow up inside containment are available, and containment integrity is preserved – hence avoiding isolation system failure. It also provides a full practical exercise where lessons learned derived from the current study – hence limited to the imposed boundary conditions – are applied. The leakage of gas from the containment to the support buildings is based on separate calculations using the EPRI-owned Modular Accident Analysis Program, MAAP4.07. The FATE™ code (facility Flow, Aerosol, Thermal, and Explosion) was used to model the transport and distribution of leaked flammable gas (H_2 and CO) in the penetration buildings. FATE models the significant mixing (dilution) which occurs as the released buoyant gas rises and entrains air. Also, FATE accounts for the condensation of steam on room surfaces, an effect which acts to concentrate flammable gas. The results of the analysis show that during a severe accident, flammable conditions are unlikely to occur in compartmentalized buildings such as the one used in the

Hypoxic pretreatment protects against neuronal damage of the rat hippocampus induced by severe hypoxia.

Science.gov (United States)

Gorgias, N; Maidatsi, P; Tsolaki, M; Alvanou, A; Kiriazis, G; Kaidoglou, K; Giala, M

1996-04-01

The present study investigates whether under conditions of successive hypoxic exposures pretreatment with mild (15% O(2)) or moderate (10% O(2)) hypoxia, protects hippocampal neurones against damage induced by severe (3% O(2)) hypoxia. The ultrastructural findings were also correlated with regional superoxide dismutase (SOD) activity changes. In unpretreated rats severe hypoxia induced ultrastructural changes consistent with the aspects of delayed neuronal death (DND). However, in preexposed animals hippocampal damage was attenuated in an inversely proportional way with the severity of the hypoxic pretreatment. The ultrastructural hypoxic tolerance findings were also closely related to increased regional SOD activity levels. Thus the activation of the endogenous antioxidant defense by hypoxic preconditioning, protects against hippocampal damage induced by severe hypoxia. The eventual contribution of increased endogenous adenosine and/or reduced excitotoxicity to induce hypoxic tolerance is discussed.

Clinical heterogeneity among people with high functioning autism spectrum conditions: evidence favouring a continuous severity gradient

Directory of Open Access Journals (Sweden)

Woodbury-Smith Marc

2008-02-01

Full Text Available Abstract Background Autism Spectrum Conditions (ASCs are characterized by a high degree of clinical heterogeneity, but the extent to which this variation represents a severity gradient versus discrete phenotypes is unclear. This issue has complicated genetic studies seeking to investigate the genetic basis of the high hereditability observed clinically in those with an ASC. The aim of this study was to examine the possible clustering of symptoms associated with ASCs to determine whether the observed distribution of symptom type and severity supported either a severity or a symptom subgroup model to account for the phenotypic variation observed within the ASCs. Methods We investigated the responses of a group of adults with higher functioning ASCs on the fifty clinical features examined in the Autism Spectrum Quotient, a screening questionnaire used in the diagnosis of higher functioning ASCs. In contrast to previous studies we have used this instrument with no a priori assumptions about any underlying factor structure of constituent items. The responses obtained were analyzed using complete linkage hierarchical cluster analysis. For the members of each cluster identified the mean score on each Autism Spectrum Quotient question was calculated. Results Autism Spectrum Quotient responses from a total of 333 individuals between the ages of 16.6 and 78.0 years were entered into the hierarchical cluster analysis. The four cluster solution was the one that generated the largest number of clusters that did not also include very small cluster sizes, defined as a membership comprising 10 individuals or fewer. Examination of these clusters demonstrated that they varied in total Autism Spectrum Quotient but that the profiles across the symptoms comprising the Autism Spectrum Quotient did not differ independently of this severity factor. Conclusion These results are consistent with a unitary spectrum model, suggesting that the clinical heterogeneity observed

Impact of desiccation and heat exposure stress on Salmonella tolerance to acidic conditions.

Science.gov (United States)

Richardson, Kurt E; Cox, Nelson A; Cosby, Douglas E; Berrang, Mark E

2018-02-01

In a recent study, the pH of commonly used Salmonella pre-enrichment media became acidic (pH 4.0 to 5.0) when feed or feed ingredients were incubated for 24 h. Acidic conditions have been reported to injure or kill Salmonella. In this study, cultures of four known feed isolates (S. montevideo, S. senftenberg, S. tennessee, and S. schwarzengrund) and four important processing plant isolates (S. typhimurium, S. enteritidis, S. infantis, and S. heidelberg) were grown on meat and bone meal and later subjected to desiccation and heat exposure to stress the microorganism. The impact of stress on the isolates ability to survive in acidic conditions ranging from pH 4.0 to 7.0 was compared to the non-stressed isolate. Cell injury was determined on xylose lysine tergitol 4 (XLT4) and cell death determined on nutrient agar (NA). When measured by cell death in non-stressed Salmonella, S. typhimurium was the most acid tolerant and S. heidelberg was the most acid sensitive whereas in stressed Salmonella, S. senftenberg was the most acid tolerant and S. tennessee was the most acid sensitive. The pH required to cause cell injury varied among isolates. With some isolates, the pH required for 50% cell death and 50% cell injury was similar. In other isolates, cell injury occurred at a more neutral pH. These findings suggest that the pH of pre-enrichment media may influence the recovery and bias the serotype of Salmonella recovered from feed during pre-enrichment.

Exposure of the general public due to wireless LAN applications in public places

International Nuclear Information System (INIS)

Schmid, G.; Preiner, P.; Lager, D.; Ueberbacher, R.; Georg, R.

2007-01-01

The typical exposure caused by wireless LAN applications in public areas has been investigated in a variety of scenarios. Small-sized (internet cafe) and large-scale (airport) indoor scenarios as well as outdoor scenarios in the environment of access points (AP) supplying for residential areas and public places were considered. The exposure assessment was carried out by numerical GTD/UTD computations based on optical wave propagation, as well as by verifying frequency selective measurements in the considered scenarios under real life conditions. In the small-sized indoor scenario the maximum temporal peak values of power density, spatially averaged over body dimensions, were found to be lower than 20 mW/m 2 , corresponding to 0.2% of the reference level according to the European Council Recommendation 1999/519/EC. Local peak values of power density might be 1-2 orders of magnitude higher, spatial and time-averaged values for usual data traffic conditions might be 2-3 orders of magnitude lower, depending on the actual data traffic. In the considered outdoor scenarios, exposure was several orders of magnitude lower than in indoor scenarios due to the usually larger distances to the AP antennas. (authors)

Acute Illness Among Surfers After Exposure to Seawater in Dry- and Wet-Weather Conditions.

Science.gov (United States)

Arnold, Benjamin F; Schiff, Kenneth C; Ercumen, Ayse; Benjamin-Chung, Jade; Steele, Joshua A; Griffith, John F; Steinberg, Steven J; Smith, Paul; McGee, Charles D; Wilson, Richard; Nelsen, Chad; Weisberg, Stephen B; Colford, John M

2017-10-01

Rainstorms increase levels of fecal indicator bacteria in urban coastal waters, but it is unknown whether exposure to seawater after rainstorms increases rates of acute illness. Our objective was to provide the first estimates of rates of acute illness after seawater exposure during both dry- and wet-weather periods and to determine the relationship between levels of indicator bacteria and illness among surfers, a population with a high potential for exposure after rain. We enrolled 654 surfers in San Diego, California, and followed them longitudinally during the 2013-2014 and 2014-2015 winters (33,377 days of observation, 10,081 surf sessions). We measured daily surf activities and illness symptoms (gastrointestinal illness, sinus infections, ear infections, infected wounds). Compared with no exposure, exposure to seawater during dry weather increased incidence rates of all outcomes (e.g., for earache or infection, adjusted incidence rate ratio (IRR) = 1.86, 95% confidence interval (CI): 1.27, 2.71; for infected wounds, IRR = 3.04, 95% CI: 1.54, 5.98); exposure during wet weather further increased rates (e.g., for earache or infection, IRR = 3.28, 95% CI: 1.95, 5.51; for infected wounds, IRR = 4.96, 95% CI: 2.18, 11.29). Fecal indicator bacteria measured in seawater (Enterococcus species, fecal coliforms, total coliforms) were strongly associated with incident illness only during wet weather. Urban coastal seawater exposure increases the incidence rates of many acute illnesses among surfers, with higher incidence rates after rainstorms. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.

Better executive function under stress mitigates the effects of recent life stress exposure on health in young adults.

Science.gov (United States)

Shields, Grant S; Moons, Wesley G; Slavich, George M

2017-01-01

Executive function is a neuropsychological construct that enables controlled cognitive processing, which has been hypothesized to enhance individuals' resilience to stress. However, little empirical work has directly examined how executive function under different conditions mitigates the negative effects of stress exposure on health. To address this issue, we recruited 110 healthy young adults and assessed their recent life stress exposure, executive function in either a stressful or non-stressful context, and current health complaints. Based on existing research, we hypothesized that individuals exhibiting better executive function following a laboratory-based stressor (but not a control task) would demonstrate weaker associations between recent stress exposure and health because they perceived recent life stressors as being less severe. Consistent with this hypothesis, better executive function during acute stress, but not in the absence of stress, was associated with an attenuated link between participants' recent life stress exposure and their current health complaints. Moreover, this attenuating effect was mediated by lesser perceptions of stressor severity. Based on these data, we conclude that better executive function under stress is associated with fewer health complaints and that these effects may occur by reducing individuals' perceptions of stressor severity. The data thus suggest the possibility of reducing stress-related health problems by enhancing executive function.

[Collagenolytic activity in several species of deuteromycetes under various storage conditions].

Science.gov (United States)

Iakovleva, M B; Khoang, T L; Nikitina, Z K

2006-01-01

The ability of deuteromycetes of the genera Penicillium, Aspergillus, and Botrytis to retain collagenolytic activity was studied after both 2 and 10 years of storage on a Czapek medium under a layer of mineral oil at 4 degrees C, as well as in silica gel granules at 20 and -60 degrees C. The enzymatic activity of several species, including Botrytis terrestris, Penicillium janthinellum, Penicillium chrysogenum, and Penicillium citrinum, was retained under both conditions of storage. Aspergillus repens retained enzymatic activity only if stored under a layer of mineral oil. The viability of conidia and the collagenolytic activity of Botrytis terrestris, P. janthinellum, P. chrysogenum, and Penicillium citrinum, maintained on silica gel for 10 years, depended on the storage temperature. The viability of the test strains improved after storage on a silica gel at -60 degrees C. A strain of Aspergillus repens lost its ability to dissolve collagen at various storage temperatures on the silica gel. The index of lysis for three strains of Penicillium deuteromycetes (Penicillium janthinellum, Penicillium chrysogenum, and Penicillium citrinum) increased after a 10-year storage on silica gel at -60 degrees C.

Effects from offshore oil production: chronic exposure of fish to produced water

Energy Technology Data Exchange (ETDEWEB)

Holth, Tor Fredrik

2009-07-01

The results of this study demonstrated that environmentally relevant levels of components of produced water may affect condition factor, maturation, biochemical processes and gene expression in fish. The usefulness of bile PAH and AP metabolite measurements to evaluate exposure was demonstrated in two fish species. The development of bio marker responses was shown to depend on exposure regime as well as exposure period. Lysosomal stability (LMS) in cod kidney was related to dose, the effects were observed early (within two weeks) and remained at a stable level throughout the exposure period in fish receiving both continuous and pulsed exposure. Thus, LMS appeared to be a useful marker for effects in Atlantic cod. Formation of DNA adducts in female cod liver was also related to dose, but in contrast to LMS, more than 16 weeks was required for formation of significant levels. This parameter may therefore be underestimated following short-term exposures, such as most offshore fish caging studies (often 4-6 weeks). Although a time-dependent increase was observed, it also required a continuous exposure regime, which is not often observed in the environment. Other bio markers were demonstrated either to adapt or appeared to be insensitive to the exposures. CYP1A activity (EROD) in female cod was responsive on occasion, but a reduction of activity over time was observed. Protein levels of vitellogenin and hepatic CYP1A in zebra fish, as well as AOX in cod kidneys, were not affected in the current study. Gene transcription of several distinct cellular mechanisms was clearly affected in both species, and a predominance of differentially expressed genes in zebra fish was down regulated. This indicated that down-regulation of responsive pathways may be as important or more important than up-regulation. As both presence and absence of effects following pulsed exposure were apparent (DNA adduct formation; oocyte maturation; condition factor), the effects of exposure regime on

Cumulative exposure to carbon monoxide during the day

Energy Technology Data Exchange (ETDEWEB)

Joumard, R. (INRETS, 69 - Bron (FR))

The carbon monoxide, CO, has the advantage of being very easily and accurately measured under various conditions. In addition, it allows the translation of CO concentrations into their biological effects. The cumulative CO exposure should be considered according to current environment conditions during a given period of life, e.g. the day. In addition, the translation of concentrations and exposure times of CO fixed on blood haemoglobine (carboxyhaemoglobine) depends on physiological factors such as age, size, sex, or physical activity. This paper gives some examples of CO exposure translated into curves of carboxyhaemoglobine: case of 92 persons whose schedule was studied in details, of customs officers whose exposure was measured during one week, or other theoretical cases. In all the cases studied, smoking is by far the first factor of pollution by carbon monoxide. If not considering this case, the CO contents observed are preoccupying for sensitive subjects (in particular children) only in very rare cases. Furthermore, this approach allows the assessment of maximal allowable concentrations during specific exposures (work, e.g. in a tunnel) by integrating them into normal life conditions and population current exposure.

Subjective Health Complaints in Individuals with Psoriasis and Psoriatic Arthritis: Associations with the Severity of the Skin Condition and Illness Perceptions - A Cross-Sectional Study.

Science.gov (United States)

Nordbø, Emma Charlott Andersson; Aamodt, Geir; Ihlebæk, Camilla Martha

2017-06-01

High comorbidity has been reported among persons with psoriasis and psoriatic arthritis (PsA), but the occurrence of subjective health complaints (SHCs) in these patient groups is poorly understood. The study aimed to describe the prevalence of SHCs among individuals with psoriasis and PsA in Norway, and investigate whether the severity of their skin condition and their illness perceptions were associated with the number and severity of health complaints. Participants were recruited through the Psoriasis and Eczema Association of Norway (PEF) (n = 942). The participants answered a self-administered questionnaire covering subjective health complaints, the severity of their skin condition, and their illness perceptions measured with the Brief Illness Perception Questionnaire (BIPQ-R). The prevalence and severity of SHCs were high. Participants with PsA reported more complaints and higher severity of complaints compared with participants with psoriasis. In both groups, the severity of the skin condition was associated with the number and severity of SHCs. Cognitive illness perceptions (consequences) and emotional illness perceptions (emotional affect) were associated with SHCs in participants with psoriasis, whereas only cognitive illness perceptions (consequences and identity) were associated with SHCs in participants with PsA. The high prevalence and severity of SHCs among individuals with psoriasis and PsA were associated with the severity of the skin condition and illness perceptions. Somatic and cognitive sensitizations are proposed as possible mechanisms. The findings suggest that holistic approaches are essential when managing these patient groups in health care institutions and clinical practice.

Assessment of the occupational exposures at two NORM industries located at the South of Spain

International Nuclear Information System (INIS)

Garcia Tenorio, Rafael; Juan Pedro, Bolivar

2008-01-01

On the frame of a broad project devoted to the control of exposures in several typical NORM industries located at the South of Spain, the evaluation of the occupational radiation exposures in two industries, one devoted to the production of phosphoric acid by the so-called 'wet-acid method' and the other devoted to the production of titanium dioxide pigments, has been performed. Internal (via inhalation) and external (via gamma) pathways of exposure have been considered in the performed evaluations, arriving in both industrial activities to the same conclusion: under normal running conditions, the increment of the occupational exposures is lower than 1 mSv/y. However, some precautions should be taken in both industries: a) In order not to change drastically the worker time occupational factors, now under application, especially in the areas with high instantaneous external dose rates and; b) During maintenance operations. (author)

Characterisation of Growth and Ultrastructural Effects of the Xanthoria elegans Photobiont After 1.5 Years of Space Exposure on the International Space Station

Science.gov (United States)

Brandt, Annette; Posthoff, Eva; de Vera, Jean-Pierre; Onofri, Silvano; Ott, Sieglinde

2016-06-01

The lichen Xanthoria elegans has been exposed to space and simulated Mars-analogue environment in the Lichen and Fungi Experiment (LIFE) on the EXPOSE-E facility at the International Space Station (ISS). This long-term exposure of 559 days tested the ability of various organisms to cope with either low earth orbit (LEO) or Mars-analogue conditions, such as vacuum, Mars-analogue atmosphere, rapid temperature cycling, cosmic radiation of up to 215 ± 16 mGy, and insolation of accumulated doses up to 4.87 GJm-2, including up to 0.314 GJm-2 of UV irradiation. In a previous study, X. elegans demonstrated considerable resistance towards these conditions by means of photosynthetic activity as well as by post-exposure metabolic activity of 50-80 % in the algal and 60-90 % in the fungal symbiont (Brandt et al. Int J Astrobiol 14(3):411-425, 2015). The two objectives of the present study were complementary: First, to verify the high post-exposure viability by using a qualitative cultivation assay. Second, to characterise the cellular damages by transmission electron microscopy (TEM) which were caused by the space and Mars-analogue exposure conditions of LIFE. Since the algal symbiont of lichens is considered as the more susceptible partner (de Vera and Ott 2010), the analyses focused on the photobiont. The study demonstrated growth and proliferation of the isolated photobiont after all exposure conditions of LIFE. The ultrastructural analysis of the algal cells provided an insight to cellular damages caused by long-term exposure and highlighted that desiccation-induced breakdown of cellular integrity is more pronounced under the more severe space vacuum than under Mars-analogue atmospheric conditions. In conclusion, desiccation-induced damages were identified as a major threat to the photobiont of X. elegans. Nonetheless, a fraction of the photobiont cells remained cultivable after all exposure conditions tested in LIFE.

The assessment of occupational protection conditions in workplaces with high levels of exposure to natural radiation. Report from a technical committee meeting. Working material

International Nuclear Information System (INIS)

2002-01-01

Occupational exposure from natural radiation is, in the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) 2000 Report, estimated to contribute to more than 80 percent of the world-wide annual collective dose from occupational exposure, uranium mining excluded. The Agency's Radiation Safety Standards Series, the Requirements, and the Safety Guides (jointly sponsored by the Agency and the International Labour Office), address the control of occupational exposures from natural sources of radiation. In addition, some Safety Reports on specific issues are in the process of being finalized. Following upon recommendations to the Agency from its Member States to provide further guidance on the control of occupational exposure to natural radiation, a Technical Committee Meeting on Assessment of Occupational Radiation Protection Conditions in Workplaces with High Levels of Exposure to Natural Radiation was held in Vienna from 7 to 11 May 2001. The objective of the meeting was to produce an inventory of problem areas, make an assessment of the problem and propose a draft work plan for the Agency, This IAEA Working Material includes the report from the meeting, including the presentations made. Based on the recommendations made by the Technical Committee, a work plan is being initiated, implying that more attention will be paid to occupational exposure from natural radiation sources in the Occupational Radiation Protection programme

Nature of activities and natural, artificial, accidental exposures. Magnitude of these exposures

International Nuclear Information System (INIS)

Aurengo, A.

2009-01-01

The exposure to ionizing radiation (I.R.) is linked to radioelements of organism (9%), earth (12%), cosmic radiation (10%), radon (37%), atmospheric fallout ( nuclear tests 2.5% and industry 0.5%) and to medical procedures (29%). The natural exposure varies in France from 2.5 to 5 mSv by year. In some areas in the world it reaches several tens of mSv by year. The medical exposure is very heterogeneous and concerns particularly old people. For a same examination, the patients exposure varies in an important way ( sometimes from 1 to 10) according to the country, even in France. In France, 250 000 persons are occupationally exposed to ionizing radiation. Among these ones, the most of cases exceeded regulatory limits for exposure to IR concern the health sector. The accidental exposures are in relation with industrial activities (51%) research (20%) civil nuclear (13%) or military (5%) and medical activities (11%). The exposures and then the consequences are very variable, ranging from death to unapparent consequences. in the most of cases a human error is involved and these accidents could have been avoided through measures of prevention and training. (N.C.)

Acute myeloid and chronic lymphoid leukaemias and exposure to low-level benzene among petroleum workers

Science.gov (United States)

Rushton, L; Schnatter, A R; Tang, G; Glass, D C

2014-01-01

Background: High benzene exposure causes acute myeloid leukaemia (AML). Three petroleum case–control studies identified 60 cases (241 matched controls) for AML and 80 cases (345 matched controls) for chronic lymphoid leukaemia (CLL). Methods: Cases were classified and scored regarding uncertainty by two haematologists using available diagnostic information. Blinded quantitative benzene exposure assessment used work histories and exposure measurements adjusted for era-specific circumstances. Statistical analyses included conditional logistic regression and penalised smoothing splines. Results: Benzene exposures were much lower than previous studies. Categorical analyses showed increased ORs for AML with several exposure metrics, although patterns were unclear; neither continuous exposure metrics nor spline analyses gave increased risks. ORs were highest in terminal workers, particularly for Tanker Drivers. No relationship was found between benzene exposure and risk of CLL, although the Australian study showed increased risks in refinery workers. Conclusion: Overall, this study does not persuasively demonstrate a risk between benzene and AML. A previously reported strong relationship between myelodysplastic syndrome (MDS) (potentially previously reported as AML) at our study's low benzene levels suggests that MDS may be the more relevant health risk for lower exposure. Higher CLL risks in refinery workers may be due to more diverse exposures than benzene alone. PMID:24357793

Response Analysis on Electrical Pulses under Severe Nuclear Accident Temperature Conditions Using an Abnormal Signal Simulation Analysis Module

Directory of Open Access Journals (Sweden)

Kil-Mo Koo

2012-01-01

Full Text Available Unlike design basis accidents, some inherent uncertainties of the reliability of instrumentations are expected while subjected to harsh environments (e.g., high temperature and pressure, high humidity, and high radioactivity occurring in severe nuclear accident conditions. Even under such conditions, an electrical signal should be within its expected range so that some mitigating actions can be taken based on the signal in the control room. For example, an industrial process control standard requires that the normal signal level for pressure, flow, and resistance temperature detector sensors be in the range of 4~20 mA for most instruments. Whereas, in the case that an abnormal signal is expected from an instrument, such a signal should be refined through a signal validation process so that the refined signal could be available in the control room. For some abnormal signals expected under severe accident conditions, to date, diagnostics and response analysis have been evaluated with an equivalent circuit model of real instruments, which is regarded as the best method. The main objective of this paper is to introduce a program designed to implement a diagnostic and response analysis for equivalent circuit modeling. The program links signal analysis tool code to abnormal signal simulation engine code not only as a one body order system, but also as a part of functions of a PC-based ASSA (abnormal signal simulation analysis module developed to obtain a varying range of the R-C circuit elements in high temperature conditions. As a result, a special function for abnormal pulse signal patterns can be obtained through the program, which in turn makes it possible to analyze the abnormal output pulse signals through a response characteristic of a 4~20 mA circuit model and a range of the elements changing with temperature under an accident condition.

Gas-phase organics in environmental tobacco smoke: 2. Exposure-relevant emission factors and indirect exposures from habitual smoking

Science.gov (United States)

Singer, Brett C.; Hodgson, Alfred T.; Nazaroff, William W.

Sorption of emitted gas-phase organic compounds onto material surfaces affects environmental tobacco smoke (ETS) composition and exposures indoors. We have introduced a new metric, the exposure relevant emission factor (EREF) that accounts for sorptive uptake and reemission to give the mass of individual ETS constituents available for exposure over a day in which smoking occurs. This paper describes month-long experiments to investigate sorption effects on EREFs and potential ETS exposures under habitual smoking conditions. Cigarettes were smoked in a 50-m 3 furnished room over a 3-h period 6-7 days per week, with continuous ventilation at 0.3, 0.6, or 2.1 h -1. Organic gas concentrations were measured every few days over 4-h "smoking", 10-h "post-smoking" and 10-h "background" periods. Concentration patterns of volatile ETS components including 1,3-butadiene, benzene and acrolein were similar to those calculated for a theoretical non-sorbing tracer, indicating limited sorption. Concentrations of ETS tracers, e.g. 3-ethenylpyridine (3-EP) and nicotine, and lower volatility toxic air contaminants including phenol, cresols, and naphthalene increased as experiments progressed, indicating mass accumulation on surfaces and higher desorption rates. Daily patterns stabilized after week 2, yielding a steady daily cycle of ETS concentrations associated with habitual smoking. EREFs for sorbing compounds were higher under steady cycle versus single-day smoking conditions by ˜50% for 3-EP, and by 2-3 times for nicotine, phenol, cresols, naphthalene, and methylnaphthalenes. Our results provide relevant information about potential indirect exposures from residual ETS (non-smoker enters room shortly after smoker finishes) and from reemission, and their importance relative to direct exposures (non-smoker present during smoking). Under the conditions examined, indirect exposures accounted for a larger fraction of total potential exposures for sorbing versus non-sorbing compounds

Nanoparticle exposure biomonitoring: exposure/effect indicator development approaches

Science.gov (United States)

Marie-Desvergne, C.; Dubosson, M.; Lacombe, M.; Brun, V.; Mossuz, V.

2015-05-01

The use of engineered nanoparticles (NP) is more and more widespread in various industrial sectors. The inhalation route of exposure is a matter of concern (adverse effects of air pollution by ultrafine particles and asbestos). No NP biomonitoring recommendations or standards are available so far. The LBM laboratory is currently studying several approaches to develop bioindicators for occupational health applications. As regards exposure indicators, new tools are being implemented to assess potentially inhaled NP in non-invasive respiratory sampling (nasal sampling and exhaled breath condensates (EBC)). Diverse NP analytical characterization methods are used (ICP-MS, dynamic light scattering and electron microscopy coupled to energy-dispersive X-ray analysis). As regards effect indicators, a methodology has been developed to assess a range of 29 cytokines in EBCs (potential respiratory inflammation due to NP exposure). Secondly, collaboration between the LBM laboratory and the EDyp team has allowed the EBC proteome to be characterized by means of an LC-MS/MS process. These projects are expected to facilitate the development of individual NP exposure biomonitoring tools and the analysis of early potential impacts on health. Innovative techniques such as field-flow fractionation combined with ICP-MS and single particle-ICPMS are currently being explored. These tools are directly intended to assist occupational physicians in the identification of exposure situations.

Nanoparticle exposure biomonitoring: exposure/effect indicator development approaches

International Nuclear Information System (INIS)

Marie-Desvergne, C; Dubosson, M; Mossuz, V; Lacombe, M; Brun, V

2015-01-01

The use of engineered nanoparticles (NP) is more and more widespread in various industrial sectors. The inhalation route of exposure is a matter of concern (adverse effects of air pollution by ultrafine particles and asbestos). No NP biomonitoring recommendations or standards are available so far. The LBM laboratory is currently studying several approaches to develop bioindicators for occupational health applications. As regards exposure indicators, new tools are being implemented to assess potentially inhaled NP in non-invasive respiratory sampling (nasal sampling and exhaled breath condensates (EBC)). Diverse NP analytical characterization methods are used (ICP-MS, dynamic light scattering and electron microscopy coupled to energy-dispersive X-ray analysis). As regards effect indicators, a methodology has been developed to assess a range of 29 cytokines in EBCs (potential respiratory inflammation due to NP exposure). Secondly, collaboration between the LBM laboratory and the EDyp team has allowed the EBC proteome to be characterized by means of an LC-MS/MS process. These projects are expected to facilitate the development of individual NP exposure biomonitoring tools and the analysis of early potential impacts on health. Innovative techniques such as field-flow fractionation combined with ICP-MS and single particle-ICPMS are currently being explored. These tools are directly intended to assist occupational physicians in the identification of exposure situations. (paper)

Severe childhood malnutrition.

Science.gov (United States)

Bhutta, Zulfiqar A; Berkley, James A; Bandsma, Robert H J; Kerac, Marko; Trehan, Indi; Briend, André

2017-09-21

The main forms of childhood malnutrition occur predominantly in children malnutrition. Here, we use the term 'severe malnutrition' to describe these conditions to better reflect the contributions of chronic poverty, poor living conditions with pervasive deficits in sanitation and hygiene, a high prevalence of infectious diseases and environmental insults, food insecurity, poor maternal and fetal nutritional status and suboptimal nutritional intake in infancy and early childhood. Children with severe malnutrition have an increased risk of serious illness and death, primarily from acute infectious diseases. International growth standards are used for the diagnosis of severe malnutrition and provide therapeutic end points. The early detection of severe wasting and kwashiorkor and outpatient therapy for these conditions using ready-to-use therapeutic foods form the cornerstone of modern therapy, and only a small percentage of children require inpatient care. However, the normalization of physiological and metabolic functions in children with malnutrition is challenging, and children remain at high risk of relapse and death. Further research is urgently needed to improve our understanding of the pathophysiology of severe malnutrition, especially the mechanisms causing kwashiorkor, and to develop new interventions for prevention and treatment.

Failure strains and proposed limit strains for an reactor pressure vessel under severe accident conditions

International Nuclear Information System (INIS)

Krieg, R.

2005-01-01

The local failure strains of essential design elements of a reactor vessel are investigated. The size influence of the structure is of special interest. Typical severe accident conditions including elevated temperatures and dynamic loads are considered. The main part of work consists of test families with specimens under uniaxial and biaxial load. Within one test family the specimen geometry and the load conditions are similar, but the size is varied up to reactor dimensions. Special attention is given to geometries with a hole or a notch causing non-uniform stress and strain distributions typical for the reactor vessel. A key problem is to determine the local failure strain. Here suitable methods had to be developed including the so-called 'vanishing gap method', and the 'forging die method'. They are based on post-test geometrical measurements of the fracture surfaces and reconstructions of the related strain fields using finite element models. The results indicate that stresses versus dimensionless deformations are approximately size independent up to failure for specimens of similar geometry under similar load conditions. Local failure strains could be determined. The values are rather high and size dependent. Statistical evaluation allow the proposal of limit strains which are also size dependent. If these limit strains are not exceeded, the structures will not fracture

Severe childhood malnutrition

DEFF Research Database (Denmark)

Bhutta, Zulfiqar A; Berkley, James A; Bandsma, Robert H J

2017-01-01

The main forms of childhood malnutrition occur predominantly in children malnutrition. Here, we use...... the term 'severe malnutrition' to describe these conditions to better reflect the contributions of chronic poverty, poor living conditions with pervasive deficits in sanitation and hygiene, a high prevalence of infectious diseases and environmental insults, food insecurity, poor maternal and fetal...... nutritional status and suboptimal nutritional intake in infancy and early childhood. Children with severe malnutrition have an increased risk of serious illness and death, primarily from acute infectious diseases. International growth standards are used for the diagnosis of severe malnutrition and provide...

Radiation exposure from incorporated isotopes

Energy Technology Data Exchange (ETDEWEB)

Beleznay, F [Hungarian Academy of Sciences, Budapest. Central Research Inst. for Physics

1985-01-01

Recommendations for the limitation of the burden of the human body from radiation exposure were developed to avoid direct radiation health damage such that the occurrence of stochastic damage can be held below a resonable risk level. The recommendations, published under ICRP 26 and ICRP 30, contain several guidelines and concepts which are discussed here. They include the primary internal dose exposure limits, secondary and implied limits for the monitoring of internal radiation exposure (Annual Limit of Intake, Derived Air Concentrations). Methods are presented for inspection and monitoring of internal exposure in medical laboratories, inspection of incorporation of sup(131)I and sup(99m)Tc.

Development of systematic models for aerosol agglomeration and spray removal under severe accident conditions

International Nuclear Information System (INIS)

Kajimoto, Mitsuhiro

2008-01-01

Radionuclide behavior during various severe accident conditions has been addressed as one of the important issues to discuss environmental safety in nuclear power plants. The present paper deals with the development of analytical models and their validations for the agglomeration of multiple-component aerosol and spray removal that controls source terms to the environment of both aerosols and gaseous radionuclides during recirculation mode operation in a containment system for a light water reactor. As for aerosol agglomeration, the single collision kernel model that can cover all types of two-body collision of aerosol was developed. In addition, the dynamic model that can treat aerosol and vapor transfer leading to the equilibrium condition under the containment spray operation was developed. The validations of the present models for multiple-component aerosol growth by agglomeration were performed by comparisons with Nuclear Safety Pilot Plant (NSPP) experiments at Oak Ridge National Laboratory (ORNL) and AB experiments at Hanford Engineering National Laboratory (HEDL). In addition, the spray removal models were applied to the analysis of containment spray experiment (CSE) at HEDL. The results calculated by the models showed good agreements with experimental results. (author)

Severe capillary leak syndrome after inner ear decompression sickness in a recreational scuba diver.

Science.gov (United States)

Gempp, Emmanuel; Lacroix, Guillaume; Cournac, Jean-Marie; Louge, Pierre

2013-07-01

Post-decompression shock with plasma volume deficit is a very rare event that has been observed under extreme conditions of hypobaric and hyperbaric exposure in aviators and professional divers. We report a case of severe hypovolemic shock due to extravasation of plasma in a recreational scuba diver presenting with inner ear decompression sickness. Impaired endothelial function can lead to capillary leak with hemoconcentration and hypotension in severe cases. This report suggests that decompression-induced circulating bubbles may have triggered the endothelial damage, activating the classic inflammatory pathway of increased vascular permeability. This observation highlights the need for an accurate diagnosis of this potentially life-threatening condition at the initial presentation in the Emergency Department after a diving-related injury. An elevated hematocrit in a diver should raise the suspicion for the potential development of capillary leak syndrome requiring specific treatment using albumin infusion as primary fluid replacement. Copyright © 2013 Elsevier Inc. All rights reserved.

Symptom Dimensions in Obsessive-Compulsive Disorder: Phenomenology and Treatment Outcomes with Exposure and Ritual Prevention

OpenAIRE

Williams, Monnica T.; Mugno, Beth; Franklin, Martin; Faber, Sonya

2013-01-01

Obsessive-compulsive disorder (OCD) is a severe condition with varied symptom presentations. The cognitive-behavioral treatment with the most empirical support is currently exposure and ritual prevention (EX/RP); however, clinical impression and some empirical data suggest that certain OCD symptoms are more responsive to treatment than others. Prior work identifying symptom dimensions within OCD is discussed, including epidemiological findings, factor analytic studies, and biological findings...

A new radiation exposure record system

International Nuclear Information System (INIS)

Lyon, M.; Berndt, V.L.; Trevino, G.W.; Oakley, B.M.

1993-04-01

The Hanford Radiological Records Program (HRRP) serves all Hanford contractors as the single repository for radiological exposure for all Hanford employees, subcontractors, and visitors. The program administers and preserves all Hanford radiation exposure records. The program also maintains a Radiation Protection Historical File which is a historical file of Hanford radiation protection and dosimetry procedures and practices. Several years ago DOE declared the existing UNIVAC mainframe computer obsolete and the existing Occupational Radiation Exposure (ORE) system was slated to be redeveloped. The new system named the Radiological Exposure (REX) System is described in this document

Timescale Correlation between Marine Atmospheric Exposure and Accelerated Corrosion Testing

Science.gov (United States)

Montgomery, Eliza L.; Calle, Luz Marina; Curran, Jerone C.; Kolody, Mark R.

2011-01-01

Evaluation of metal-based structures has long relied on atmospheric exposure test sites to determine corrosion resistance in marine environments. Traditional accelerated corrosion testing relies on mimicking the exposure conditions, often incorporating salt spray and ultraviolet (UV) radiation, and exposing the metal to continuous or cyclic conditions of the corrosive environment. Their success for correlation to atmospheric exposure is often a concern when determining the timescale to which the accelerated tests can be related. Accelerated laboratory testing, which often focuses on the electrochemical reactions that occur during corrosion conditions, has yet to be universally accepted as a useful tool in predicting the long term service life of a metal despite its ability to rapidly induce corrosion. Although visual and mass loss methods of evaluating corrosion are the standard and their use is imperative, a method that correlates timescales from atmospheric exposure to accelerated testing would be very valuable. This work uses surface chemistry to interpret the chemical changes occurring on low carbon steel during atmospheric and accelerated corrosion conditions with the objective of finding a correlation between its accelerated and long-term corrosion performance. The current results of correlating data from marine atmospheric exposure conditions at the Kennedy Space Center beachside corrosion test site, alternating seawater spray, and immersion in typical electrochemical laboratory conditions, will be presented. Key words: atmospheric exposure, accelerated corrosion testing, alternating seawater spray, marine, correlation, seawater, carbon steel, long-term corrosion performance prediction, X-ray photoelectron spectroscopy.

Comparison of modeled estimates of inhalation exposure to aerosols during use of consumer spray products.

Science.gov (United States)

Park, Jihoon; Yoon, Chungsik; Lee, Kiyoung

2018-05-30

In the field of exposure science, various exposure assessment models have been developed to complement experimental measurements; however, few studies have been published on their validity. This study compares the estimated inhaled aerosol doses of several inhalation exposure models to experimental measurements of aerosols released from consumer spray products, and then compares deposited doses within different parts of the human respiratory tract according to deposition models. Exposure models, including the European Center for Ecotoxicology of Chemicals Targeted Risk Assessment (ECETOC TRA), the Consumer Exposure Model (CEM), SprayExpo, ConsExpo Web and ConsExpo Nano, were used to estimate the inhaled dose under various exposure scenarios, and modeled and experimental estimates were compared. The deposited dose in different respiratory regions was estimated using the International Commission on Radiological Protection model and multiple-path particle dosimetry models under the assumption of polydispersed particles. The modeled estimates of the inhaled doses were accurate in the short term, i.e., within 10 min of the initial spraying, with a differences from experimental estimates ranging from 0 to 73% among the models. However, the estimates for long-term exposure, i.e., exposure times of several hours, deviated significantly from the experimental estimates in the absence of ventilation. The differences between the experimental and modeled estimates of particle number and surface area were constant over time under ventilated conditions. ConsExpo Nano, as a nano-scale model, showed stable estimates of short-term exposure, with a difference from the experimental estimates of less than 60% for all metrics. The deposited particle estimates were similar among the deposition models, particularly in the nanoparticle range for the head airway and alveolar regions. In conclusion, the results showed that the inhalation exposure models tested in this study are suitable

Exposure Plus Response-Prevention Treatment of Bulimia Nervosa.

Science.gov (United States)

Leitenberg, Harold; And Others

1988-01-01

Evaluated exposure plus response-prevention treatment of bulimia nervosa among 47 women. Subjects were assigned to either exposure plus response-prevention in one setting, exposure plus response-prevention in multiple settings, cognitive-behavioral therapy, or waiting-list control conditions. Found three treatment groups improved significantly on…

Investigation of Focusing Effect according to the Cooling Condition and Height of the Metallic layer in a Severe Accident

Energy Technology Data Exchange (ETDEWEB)

Moon, Je-Young; Chung, Bum-Jin [Kyung Hee University, Yongin (Korea, Republic of)

2015-05-15

The Fukushima nuclear power plant accident has led to renewed research interests in severe accidents of nuclear power plants. In-Vessel Retention (IVR) of core melt is one of key severe accident management strategies adopted in nuclear power plant design. The metallic layer is heated from below by the radioactive decay heat generated at the oxide pool, and is cooled from above and side walls. During the IVR process, reactor vessel may be cooled externally (ERVC) and the heat fluxes to the side wall increase with larger temperature difference than above. This {sup F}ocusing effect{sup i}s varied by cooling condition of upper boundary and height of the metallic layer. A sulfuric acid–copper sulfate (H{sub 2}SO{sub 4} - CuSO{sub 4}) electroplating system was adopted as the mass transfer system. Numerical analysis using the commercial CFD program FLUENT 6.3 were carried out with the same material properties and cooling conditions to examine the variation of the cell. The experimental and numerical studies were performed to investigate the focusing effect according to cooling condition of upper boundary and the height in metallic layer. The height of the side wall was varied for three different cooling conditions: top only, side only, and both top and side. Mass transfer experiments, based on the analogy concept, were carried out in order to achieve high Rayleigh number. The experimental results agreed well with the Rayleigh-Benard convection correlations of Dropkin and Somerscales and Globe and Dropkin. The heat transfer on side wall cooling condition without top cooling is highest and was enhanced by decreasing the aspect ratio. The numerical results agreed well with the experimental results. Each cell pattern (cell size, cell direction, central location of cell) differed in the cooling condition. Therefore, it is difficult to predict the internal flow due to complexity of cell formation behavior.

Anxiety symptoms mediate the relationship between exposure to stressful negative life events and depressive symptoms: A conditional process modelling of the protective effects of resilience.

Science.gov (United States)

Anyan, Frederick; Worsley, Lyn; Hjemdal, Odin

2017-10-01

Resilience has provided a useful framework that elucidates the effects of protective factors to overcome psychological adversities but studies that address the potential contingencies of resilience to protect against direct and indirect negative effects are lacking. These obvious gaps have also resulted in oversimplification of complex processes that can be clarified by moderated mediation associations. This study examines a conditional process modelling of the protective effects of resilience against indirect effects. Two separate samples were recruited in a cross-sectional survey from Australia and Norway to complete the Patient Health Questionnaire -9, Generalized Anxiety Disorder, Stressful Negative Life Events Questionnaire and the Resilience Scale for Adults. The final sample sizes were 206 (females=114; males=91; other=1) and 210 (females=155; males=55) for Australia and Norway respectively. Moderated mediation analyses were conducted across the samples. Anxiety symptoms mediated the relationship between exposure to stressful negative life events and depressive symptoms in both samples. Conditional indirect effects of exposure to stressful negative life events on depressive symptoms mediated by anxiety symptoms showed that high subgroup of resilience was associated with less effect of exposure to stressful negative life events through anxiety symptoms on depressive symptoms than the low subgroup of resilience. As a cross-sectional survey, the present study does not answer questions about causal processes despite the use of a conditional process modelling. These findings support that, resilience protective resources can protect against both direct and indirect - through other channels - psychological adversities. Copyright © 2017 Elsevier B.V. All rights reserved.

Exposure to Folate Receptor Alpha Antibodies during Gestation and Weaning Leads to Severe Behavioral Deficits in Rats: A Pilot Study.

Directory of Open Access Journals (Sweden)

Jeffrey M Sequeira

Full Text Available The central nervous system continues to develop during gestation and after birth, and folate is an essential nutrient in this process. Folate deficiency and folate receptor alpha autoantibodies (FRα-AuAb have been associated with pregnancy-related complications and neurodevelopmental disorders. In this pilot study, we investigated the effect of exposure to FRα antibodies (Ab during gestation (GST, the pre-weaning (PRW, and the post weaning (POW periods on learning and behavior in adulthood in a rat model. In the open field test and novel object recognition task, which examine locomotor activity and anxiety-like behavior, deficits in rats exposed to Ab during gestation and pre-weaning (GST+PRW included more time spent in the periphery or corner areas, less time in the central area, frequent self-grooming akin to stereotypy, and longer time to explore a novel object compared to a control group; these are all indicative of increased levels of anxiety. In the place avoidance tasks that assess learning and spatial memory formation, only 30% of GST+PRW rats were able to learn the passive place avoidance task. None of these rats learned the active place avoidance task indicating severe learning deficits and cognitive impairment. Similar but less severe deficits were observed in rats exposed to Ab during GST alone or only during the PRW period, suggesting the extreme sensitivity of the fetal as well as the neonatal rat brain to the deleterious effects of exposure to Ab during this period. Behavioral deficits were not seen in rats exposed to antibody post weaning. These observations have implications in the pathology of FRα-AuAb associated with neural tube defect pregnancy, preterm birth and neurodevelopmental disorders including autism.

A randomized controlled study of power posing before public speaking exposure for social anxiety disorder: No evidence for augmentative effects.

Science.gov (United States)

Davis, Michelle L; Papini, Santiago; Rosenfield, David; Roelofs, Karin; Kolb, Sarah; Powers, Mark B; Smits, Jasper A J

2017-12-01

This manuscript details a randomized controlled study designed to test the efficacy of power posing (i.e., briefly holding postures associated with dominance and power) as an augmentative strategy for exposure therapy for social anxiety disorder (SAD). Seventy-three individuals diagnosed with SAD were assigned to one of three conditions: power posing, submissive posing, or rest (no posing) prior to participating in an exposure therapy session. Participants were assessed for between-group differences in pre- and post-manipulation salivary hormone levels, within-session subjective experiences of fear, and pre- and 1-week post-treatment SAD severity outcome measures. Though the intervention resulted in decreased SAD symptom severity one week later, analyses revealed no significant between-group differences on any tested variables. Accordingly, this study provides no evidence to suggest that power posing impacts hormone levels or exposure therapy outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Mere Exposure Instruction Effect.

Science.gov (United States)

Van Dessel, Pieter; Mertens, Gaëtan; Smith, Colin Tucker; De Houwer, Jan

2017-09-01

The mere exposure effect refers to the well-established finding that people evaluate a stimulus more positively after repeated exposure to that stimulus. We investigated whether a change in stimulus evaluation can occur also when participants are not repeatedly exposed to a stimulus, but are merely instructed that one stimulus will occur frequently and another stimulus will occur infrequently. We report seven experiments showing that (1) mere exposure instructions influence implicit stimulus evaluations as measured with an Implicit Association Test (IAT), personalized Implicit Association Test (pIAT), or Affect Misattribution Procedure (AMP), but not with an Evaluative Priming Task (EPT), (2) mere exposure instructions influence explicit evaluations, and (3) the instruction effect depends on participants' memory of which stimulus will be presented more frequently. We discuss how these findings inform us about the boundary conditions of mere exposure instruction effects, as well as the mental processes that underlie mere exposure and mere exposure instruction effects.

The effects of in utero bisphenol A exposure on reproductive capacity in several generations of mice

International Nuclear Information System (INIS)

Ziv-Gal, Ayelet; Wang, Wei; Zhou, Changqing; Flaws, Jodi A.

2015-01-01

In utero bisphenol A (BPA) exposure affects reproductive function in the first generation (F1) of mice; however, not many studies have examined the reproductive effects of BPA exposure on subsequent generations. In this study, pregnant mice (F0) were orally dosed with vehicle, BPA (0.5, 20, and 50 μg/kg/day) or diethylstilbestrol (DES; 0.05 μg/kg/day) daily from gestation day 11 until birth. F1 females were used to generate the F2 generation, and F2 females were used to generate the F3 generation. Breeding studies at the ages of 3, 6, and 9 months were conducted to evaluate reproductive capacity over time. Further, studies were conducted to evaluate pubertal onset, litter size, and percentage of dead pups; and to calculate pregnancy rate, and mating, fertility, and gestational indices. The results indicate that BPA exposure (0.5 and 50 μg/kg/day) significantly delayed the age at vaginal opening in the F3 generation compared to vehicle control. Both DES (0.05 μg/kg/day) and BPA (50 μg/kg/day) significantly delayed the age at first estrus in the F3 generation compared to vehicle control. BPA exposure reduced gestational index in the F1 and F2 generations compared to control. Further, BPA exposure (0.5 μg/kg/day) compromised the fertility index in the F3 generation compared to control. Finally, in utero BPA exposure reduced the ability of female mice to maintain pregnancies as they aged. Collectively, these data suggest that BPA exposure affects reproductive function in female mice and that some effects may be transgenerational in nature. - Highlights: • In utero BPA delayed vaginal opening in the F3 generation compared to control. • In utero BPA delayed estrus in the F3 generation compared to control. • In utero BPA reduced the ability of F1 and F2 female mice to maintain pregnancies. • In utero BPA compromised the ability of F3 female mice to become pregnant. • Some effects of in utero BPA may be transgenerational in nature

The effects of in utero bisphenol A exposure on reproductive capacity in several generations of mice

Energy Technology Data Exchange (ETDEWEB)

Ziv-Gal, Ayelet, E-mail: zivgal1@illinois.edu; Wang, Wei, E-mail: weiwang2@illinois.edu; Zhou, Changqing, E-mail: czhou27@illinois.edu; Flaws, Jodi A., E-mail: jflaws@illinois.edu

2015-05-01

In utero bisphenol A (BPA) exposure affects reproductive function in the first generation (F1) of mice; however, not many studies have examined the reproductive effects of BPA exposure on subsequent generations. In this study, pregnant mice (F0) were orally dosed with vehicle, BPA (0.5, 20, and 50 μg/kg/day) or diethylstilbestrol (DES; 0.05 μg/kg/day) daily from gestation day 11 until birth. F1 females were used to generate the F2 generation, and F2 females were used to generate the F3 generation. Breeding studies at the ages of 3, 6, and 9 months were conducted to evaluate reproductive capacity over time. Further, studies were conducted to evaluate pubertal onset, litter size, and percentage of dead pups; and to calculate pregnancy rate, and mating, fertility, and gestational indices. The results indicate that BPA exposure (0.5 and 50 μg/kg/day) significantly delayed the age at vaginal opening in the F3 generation compared to vehicle control. Both DES (0.05 μg/kg/day) and BPA (50 μg/kg/day) significantly delayed the age at first estrus in the F3 generation compared to vehicle control. BPA exposure reduced gestational index in the F1 and F2 generations compared to control. Further, BPA exposure (0.5 μg/kg/day) compromised the fertility index in the F3 generation compared to control. Finally, in utero BPA exposure reduced the ability of female mice to maintain pregnancies as they aged. Collectively, these data suggest that BPA exposure affects reproductive function in female mice and that some effects may be transgenerational in nature. - Highlights: • In utero BPA delayed vaginal opening in the F3 generation compared to control. • In utero BPA delayed estrus in the F3 generation compared to control. • In utero BPA reduced the ability of F1 and F2 female mice to maintain pregnancies. • In utero BPA compromised the ability of F3 female mice to become pregnant. • Some effects of in utero BPA may be transgenerational in nature.

The Specific Features of the Course of Critical Conditions in Miners

Directory of Open Access Journals (Sweden)

V. V. Moroz

2012-01-01

Full Text Available Objective: to improve treatment results in miners, by studying the specific features of the course of their critical conditions caused by severe traumatic injuries, and to develop differentiated intensive therapeutic regimens for detected abnormalities. Subjects and methods. A total of 1107 subjects were examined during the study. Central hemodynamic function was explored in 371 healthy miners with various lengths of underground mining; a control group included 30 healthy volunteers unexposed to occupational hazards. Examinations were made in 386 severe brain injury victims, including 218 victims with no length of underground work and 115 injured miners with an underground work length of more than 5 years. A control group comprised 53 apparently healthy donors. One hundred and twenty-two miners with severe thermal injury were examined. A control group consisted of 39 apparently healthy volunteers. One hundred and six victims with acute respiratory distress syndrome in the presence of severe concomitant injury were examined under mechanical ventilation. Sixty-three injured miners formed a study group; a comparison group included 43 subjects with no length of underground mining. Conclusion. Upon longer exposure to occupational hazards, the prenosological changes occur in the miners' organs and systems, which display a regular phasic pattern, fit in the picture of general adjustment syndrome, and determine the specific features of critical conditions. The peculiarities of the critical conditions caused by severe traumatic injuries in miners are the early development and high frequency of complications, the more severe course and late recovery of the body's lost functions, unlike the victims unexposed to occupational hazards. Differentiated intensive therapy for critical conditions in miners with severe traumatic injuries makes it possible to improve treatment results and to reduce death rates. 

Occupational noise exposure, psychosocial working conditions and the risk of tinnitus

DEFF Research Database (Denmark)

Frederiksen, Thomas Winther; Ramlau-Hansen, Cecilia Høst; Stokholm, Zara Ann

2017-01-01

PURPOSE: The purpose of this study was to evaluate the influence of occupational noise (current and cumulative doses) and psychosocial work factors (psychological demands and decision latitude) on tinnitus occurrence among workers, using objective and non-self-reported exposure measures to preven...

Hypertension prevalence and living conditions related to air pollution: results of a national epidemiological study in Lebanon.

Science.gov (United States)

Salameh, Pascale; Chahine, Mirna; Hallit, Souheil; Farah, Rita; Zeidan, Rouba Karen; Asmar, Roland; Hosseiny, Hassan

2018-04-01

Hypertension is a risk factor of several diseases, linked to high mortality and morbidity, particularly in developing countries. Some studies have linked indoor and outdoor pollution exposure items to hypertension, but results were inconsistent. Our objective was to assess the association of living conditions related to air pollution to hypertension in Lebanon, a Middle Eastern country. A national cross-sectional study was conducted all over Lebanon. Blood pressure and its related medications were assessed to be able to classify participants as hypertensive or not. Moreover, in addition to living conditions related to air pollution exposure, we assessed potential predictors of hypertension, including sociodemographic characteristics, self-reported health information and biological measurements. Furthermore, we assessed dose-effect relationship of air pollution items in relation with hypertension. Living conditions related to indoor and outdoor air pollution exposures were associated with hypertension, with or without taking biological values into account. Moreover, we found a dose-effect relationship of exposure with risk of disease (15% increase in risk of disease for every additional pollution exposure item), after adjustment for sociodemographics and biological characteristics (Ora = 1.15 [1.03-1.28]). Although additional studies would be necessary to confirm these findings, interventions should start to sensitize the population about the effect of air pollution on chronic diseases. The work on reducing pollution and improving air quality should be implemented to decrease the disease burden on the population and health system.

Disease awareness advertising - women's intentions following exposure.

Science.gov (United States)

Hall, Danika; Jones, Sandra; Iverson, Don

2011-03-01

In Australia, where direct to consumer advertising of prescription medicines is prohibited, pharmaceutical companies can sponsor disease awareness advertising targeting consumers. This study examined the impact of disease awareness advertising exposure on older women's reported behavioural intentions. Women were approached in a shopping centre and randomly assigned mock advertisements for two health conditions. Disease information and sponsors were manipulated. Two hundred and forty-one women responded to 466 advertisements. Almost half reported an intention to ask their doctor for a prescription or referral as a result of seeing the advertisement, but more reported they would talk to their doctor and ask about treatments and tests. Participants were more likely to report an intention to ask for prescriptions if they perceived the health condition to be severe and themselves susceptible or if they had viewed advertisements containing limited information on the disease. Disease awareness advertising may stimulate demand for prescription medicine products. This has serious implications for general practitioners and regulators.

Common paths to ASD severity and PTSD severity

DEFF Research Database (Denmark)

Hansen, Maj; Armour, Cherie; Wittmann, Lutz

Numerous studies have identified risk factors for acute and long term posttraumatic symptoms following traumatic exposure. However, little is known about possible common pathways to the development of acute stress disorder (ASD) and posttraumatic stress disorder (PTSD). Research suggests that a c......Numerous studies have identified risk factors for acute and long term posttraumatic symptoms following traumatic exposure. However, little is known about possible common pathways to the development of acute stress disorder (ASD) and posttraumatic stress disorder (PTSD). Research suggests...... that a common pathway to ASD and PTSD may lie in peritraumatic responses and cognitions. Using structural equation modeling we examined the role of three peritraumatic factors (tonic immobility, panic and dissociation) and three cognitive factors (anxiety sensitivity, negative cognitions about the world......, and negative cognitions about self ) on the development of ASD and PTSD severity in a national study of Danish bank robbery victims (N = 450). Peritraumatic panic, anxiety sensitivity, and negative cognitions about self were found to be significant common risk factors, whereas peritraumatic dissociation...

Inclusion of models to describe severe accident conditions in the fuel simulation code DIONISIO

Energy Technology Data Exchange (ETDEWEB)

Lemes, Martín; Soba, Alejandro [Sección Códigos y Modelos, Gerencia Ciclo del Combustible Nuclear, Comisión Nacional de Energía Atómica, Avenida General Paz 1499, 1650 San Martín, Provincia de Buenos Aires (Argentina); Daverio, Hernando [Gerencia Reactores y Centrales Nucleares, Comisión Nacional de Energía Atómica, Avenida General Paz 1499, 1650 San Martín, Provincia de Buenos Aires (Argentina); Denis, Alicia [Sección Códigos y Modelos, Gerencia Ciclo del Combustible Nuclear, Comisión Nacional de Energía Atómica, Avenida General Paz 1499, 1650 San Martín, Provincia de Buenos Aires (Argentina)

2017-04-15

The simulation of fuel rod behavior is a complex task that demands not only accurate models to describe the numerous phenomena occurring in the pellet, cladding and internal rod atmosphere but also an adequate interconnection between them. In the last years several models have been incorporated to the DIONISIO code with the purpose of increasing its precision and reliability. After the regrettable events at Fukushima, the need for codes capable of simulating nuclear fuels under accident conditions has come forth. Heat removal occurs in a quite different way than during normal operation and this fact determines a completely new set of conditions for the fuel materials. A detailed description of the different regimes the coolant may exhibit in such a wide variety of scenarios requires a thermal-hydraulic formulation not suitable to be included in a fuel performance code. Moreover, there exist a number of reliable and famous codes that perform this task. Nevertheless, and keeping in mind the purpose of building a code focused on the fuel behavior, a subroutine was developed for the DIONISIO code that performs a simplified analysis of the coolant in a PWR, restricted to the more representative situations and provides to the fuel simulation the boundary conditions necessary to reproduce accidental situations. In the present work this subroutine is described and the results of different comparisons with experimental data and with thermal-hydraulic codes are offered. It is verified that, in spite of its comparative simplicity, the predictions of this module of DIONISIO do not differ significantly from those of the specific, complex codes.

Vertical flow constructed wetlands for domestic wastewater treatment on tropical conditions: effect of several design parameters

DEFF Research Database (Denmark)

Bohorquez, Eliana; Paredes, Diego; Arias, Carlos Alberto

Vertical flow constructed wetlands (VFWC) design and operation takes into account several variables which affect performance its performance. These aspects had been evaluated and documented among others in countries like USA, Denmark, Austria. In contrast, VFCW had not been studied in tropical...... countries and, specifically in Colombia, design and operation parameters are not defined yet. The objective of this study was evaluate the effects of filter medium, the feeding frequency and Heliconia psittacorum presence, a typical local plant, on the domestic wastewater treatment in tropical conditions....

Relations of Change in Condition Severity and School Self-Concept To Change in Achievement-Related Behavior in Children with Asthma or Epilepsy.

Science.gov (United States)

Huberty, Thomas J.; Austin, Joan K.; Huster, Gertrude A.; Dunn, David W.

2000-01-01

Explores relation of gender, change in condition of severity, and change in school self-concept, to change in teachers' ratings of academic-related behaviors in children with asthma or epilepsy. Tests showed that these children were near population mean in academic-related behaviors, except students with high-severity epilepsy. (Author/JDM)

Development of acute exposure guideline levels for airborne exposures to hazardous substances.

Science.gov (United States)

Krewski, Daniel; Bakshi, Kulbir; Garrett, Roger; Falke, Ernest; Rusch, George; Gaylor, David

2004-04-01

Hazardous substances can be released into the atmosphere due to industrial and transportation accidents, fires, tornadoes, earthquakes, and terrorists, thereby exposing workers and the nearby public to potential adverse health effects. Various enforceable guidelines have been set by regulatory agencies for worker and ambient air quality. However, these exposure levels generally are not applicable to rare lifetime acute exposures, which possibly could occur at high concentrations. Acute exposure guideline levels (AEGLs) provide estimates of concentrations for airborne exposures for an array of short durations that possibly could cause mild (AEGL-1), severe, irreversible, potentially disabling adverse health effects (AEGL-2), or life threatening effects (AEGL-3). These levels can be useful for emergency responders and planners in reducing or eliminating potential risks to the public. Procedures and methodologies for deriving AEGLs are reviewed in this paper that have been developed in the United States, with direct input from international representatives of OECD member-countries, by the National Advisory Committee for Acute Exposure Guidelines for Hazardous Substances and reviewed by the National Research Council. Techniques are discussed for the extrapolation of effects across different exposure durations. AEGLs provide a viable approach for assisting in the prevention, planning, and response to acute airborne exposures to toxic agents.

The sources of radiation exposure

International Nuclear Information System (INIS)

Bennett, B.G.

1992-01-01

Radiation protection of workers and of members of the public requires an assessment of the various sources of exposure, their variations in time or under specific conditions or circumstances, and the possibilities for control or limitation. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has evaluated the various components of natural and man-made sources in some detail. Natural exposures form the largest component of radiation exposure of man. Variability in exposures depends on elevation, the concentrations of radionuclides in soil, food and water, the composition of building materials and the susceptibility of indoor spaces to radon build-up. Man-made sources have included exposures to fallout from atmospheric nuclear testing and discharged from nuclear fuel cycle installations in routine operations or in accidents. The other main source of radiation exposures of individuals is in medical diagnostic examinations and therapeutic treatments. (author)

Toxicokinetics of perfluorooctane sulfonate in rabbits under environmentally realistic exposure conditions and comparative assessment between mammals and birds.

Science.gov (United States)

Tarazona, J V; Rodríguez, C; Alonso, E; Sáez, M; González, F; San Andrés, M D; Jiménez, B; San Andrés, M I

2016-01-22

This article describes the toxicokinetics of perfluorooctane sulfonate (PFOS) in rabbits under low repeated dosing, equivalent to 0.085μg/kg per day, and the observed differences between rabbits and chickens. The best fitting for both species was provided by a simple pseudo monocompartmental first-order kinetics model, regulated by two rates, and accounting for real elimination as well as binding of PFOS to non-exchangeable structures. Elimination was more rapid in rabbits, with a pseudo first-order dissipation half-life of 88 days compared to the 230 days observed for chickens. By contrast, the calculated assimilation efficiency for rabbits was almost 1, very close to full absorption, significantly higher than the 0.66 with confidence intervals of 0.64 and 0.68 observed for chickens. The results confirm a very different kinetics than that observed in single-dose experiments confirming clear dose-related differences in apparent elimination rates in rabbits, as previously described for humans and other mammals; suggesting the role of a capacity-limited saturable process resulting in different kinetic behaviours for PFOS in high dose versus environmentally relevant low dose exposure conditions. The model calculations confirmed that the measured maximum concentrations were still far from the steady state situation, and that the different kinetics between birds and mammals should may play a significant role in the biomagnifications assessment and potential exposure for humans and predators. For the same dose regime, the steady state concentration was estimated at about 36μg PFOS/L serum for rabbits, slightly above one-half of the 65μg PFOS/L serum estimated for chickens. The toxicokinetic parameters presented here can be used for higher-tier bioaccumulation estimations of PFOS in rabbits and chickens as starting point for human health exposure assessments and as surrogate values for modeling PFOS kinetics in wild mammals and bird in exposure assessment of predatory

Ultra-high temperature tensile properties of ODS steel claddings under severe accident conditions

Energy Technology Data Exchange (ETDEWEB)

Yano, Y., E-mail: yano.yasuhide@jaea.go.jp [Japan Atomic Energy Agency, 4002, Narita-cho, Oarai-machi, Ibaraki, 311-1393 (Japan); Tanno, T.; Oka, H.; Ohtsuka, S.; Inoue, T.; Kato, S.; Furukawa, T.; Uwaba, T.; Kaito, T. [Japan Atomic Energy Agency, 4002, Narita-cho, Oarai-machi, Ibaraki, 311-1393 (Japan); Ukai, S.; Oono, N. [Materials Science and Engineering, Faculty of Engineering, Hokkaido University, N13, W-8, Kita-ku, Sapporo, Hokkaido, 060-8628 (Japan); Kimura, A. [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Hayashi, S. [Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8550 (Japan); Torimaru, T. [Nippon Nuclear Fuel Development Co., Ltd., 2163, Narita-cho, Oarai-machi, Ibaraki, 311-1313 (Japan)

2017-04-15

Ultra-high temperature ring tensile tests were performed to investigate the tensile behavior of oxide dispersion strengthened (ODS) steel claddings and wrapper materials under severe accident conditions with temperatures ranging from room temperature to 1400 °C which is close to the melting point of core materials. The experimental results showed that the tensile strength of 9Cr-ODS steel claddings was highest in the core materials at ultra-high temperatures of 900–1200 °C, but there was significant degradation in the tensile strength of 9Cr-ODS steel claddings above 1200 °C. This degradation was attributed to grain boundary sliding deformation with γ/δ transformation, which is associated with reduced ductility. By contrast, the tensile strength of recrystallized 12Cr-ODS and FeCrAl-ODS steel claddings retained its high value above 1200 °C, unlike the other tested materials.

Ultra-high temperature tensile properties of ODS steel claddings under severe accident conditions

Science.gov (United States)

Yano, Y.; Tanno, T.; Oka, H.; Ohtsuka, S.; Inoue, T.; Kato, S.; Furukawa, T.; Uwaba, T.; Kaito, T.; Ukai, S.; Oono, N.; Kimura, A.; Hayashi, S.; Torimaru, T.

2017-04-01

Ultra-high temperature ring tensile tests were performed to investigate the tensile behavior of oxide dispersion strengthened (ODS) steel claddings and wrapper materials under severe accident conditions with temperatures ranging from room temperature to 1400 °C which is close to the melting point of core materials. The experimental results showed that the tensile strength of 9Cr-ODS steel claddings was highest in the core materials at ultra-high temperatures of 900-1200 °C, but there was significant degradation in the tensile strength of 9Cr-ODS steel claddings above 1200 °C. This degradation was attributed to grain boundary sliding deformation with γ/δ transformation, which is associated with reduced ductility. By contrast, the tensile strength of recrystallized 12Cr-ODS and FeCrAl-ODS steel claddings retained its high value above 1200 °C, unlike the other tested materials.

Assessment of Dust Emission and Working Conditions in the Bamboo and Wooden Furniture Industries in Malaysia

Directory of Open Access Journals (Sweden)

Jegatheswaran Ratnasingam

2015-12-01

Full Text Available A study was carried out to assess the dust emission and working conditions in the bamboo and rubberwood furniture manufacturing industries in Malaysia. The emission of wood dust arising from these industries was measured in each main work station in the mills. Meanwhile, a questionnaire-based survey was conducted among 5900 workers in 45 companies to obtain information on the occupational accidents that occurred in the mills. The data were collected, compiled, and analyzed using the SPSS package. The highest dust emission from the sanding operation resulted in respiratory ailments among workers. The occurrence of injuries particularly to the hand, wrist, fingers and forearm was due to the prevailing working conditions, safety climate and workers characteristics. The dust exposure levels and working conditions were much more severe in the bamboo furniture manufacturing industry. As a result, a review of existing of dust exposure levels in the woodworking industry is warranted.

Short-term dermal exposure to tannery effluent does not cause behavioral changes in male Swiss mice

Directory of Open Access Journals (Sweden)

Bruna de Oliveira Mendes

2018-02-01

Full Text Available Tannery is a highly polluting activity due to the waste generated by bovine skin processing. Although there are several studies highlighting the health issues faced by workers exposed to tannery effluent, there are no records of experiments testing the neurobehavioral effects resulting from direct contact with this pollutant. Thus, the aim of the current study is to assess the possible neurobehavioral effects of dermal exposure to tannery effluent on male Swiss mice. Animals were divided in three groups, which were subjected to the same experimental time period and conditions: effluent group - animals in direct contact with tannery effluent (for 20 days; control group - animals in contact with pure water; and dry-control group - animals not exposed to water or to tannery effluent. Neurobehavioral tests started on the 17th experimental day. Results of the elevated plus-maze test (anxiety prediction showed no anxiogenic or anxiolytic effects, memory deficit or depressive symptoms on animals exposed to tannery effluent. Thus, the current results do not support the hypothesis that male Swiss mice dermal exposure to tannery effluents for the same time period and experimental conditions leads to neurobehavioral changes. Therefore, the herein adopted exposure protocol was not good to study the effects of dermal exposure to tannery effluent on the chosen experimental model.

Potential for containment leak paths through electrical penetration assemblies under severe accident conditions. [PWR; BWR

Energy Technology Data Exchange (ETDEWEB)

Sebrell, W.

1983-07-01

The leakage behavior of containments beyond design conditions and knowledge of failure modes is required for evaluation of mitigation strategies for severe accidents, risk studies, emergency preparedness planning, and siting. These studies are directed towards assessing the risk and consequences of severe accidents. An accident sequence analysis conducted on a Boiling Water Reactor (BWR), Mark I (MK I), indicated very high temperatures in the dry-well region, which is the location of the majority of electrical penetration assemblies. Because of the high temperatures, it was postulated in the ORNL study that the sealants would fail and all the electrical penetration assemblies would leak before structural failure would occur. Since other containments had similar electrical penetration assemblies, it was concluded that all containments would experience the same type of failure. The results of this study, however, show that this conclusion does not hold for PWRs because in the worst accident sequence, the long time containment gases stabilize to 350/sup 0/F. BWRs, on the other hand, do experience high dry-well temperatures and have a higher potential for leakage.

Environmental exposure to benzene: an update.

OpenAIRE

Wallace, L

1996-01-01

During the 1990s, several large-scale studies of benzene concentrations in air, food, and blood have added to our knowledge of its environmental occurrence. In general, the new studies have confirmed the earlier findings of the U.S. Environmental Protection Agency Total Exposure Assessment Methodology (TEAM) studies and other large-scale studies in Germany and the Netherlands concerning the levels of exposure and major sources. For example, the new studies found that personal exposures exceed...

Radically Reducing Radiation Exposure during Routine Medical Imaging

Science.gov (United States)

Exposure to radiation from medical imaging in the United States has increased dramatically. NCI and several partner organizations sponsored a 2011 summit to promote efforts to reduce radiation exposure from medical imaging.

Elodea nuttallii exposure to mercury exposure under enhanced ultraviolet radiation: Effects on bioaccumulation, transcriptome, pigment content and oxidative stress.

Science.gov (United States)

Regier, Nicole; Beauvais-Flück, Rebecca; Slaveykova, Vera I; Cosio, Claudia

2016-11-01

The hypothesis that increased UV radiation result in co-tolerance to Hg toxicity in aquatic plants was studied at the physiological and transcriptomic level in Elodea nuttallii. At the transcriptomic level, combined exposure to UV+Hg enhanced the stress response in comparison with single treatments, affecting the expression level of transcripts involved in energy metabolism, lipid metabolism, nutrition, and redox homeostasis. Single and combined UV and Hg treatments dysregulated different genes but with similar functions, suggesting a fine regulation of the plant to stresses triggered by Hg, UV and their combination but lack of co-tolerance. At the physiological level, UV+Hg treatment reduced chlorophyll content and depleted antioxidative compounds such as anthocyanin and GSH/GSSG in E. nuttallii. Nonetheless, combined exposure to UV+Hg resulted in about 30% reduction of Hg accumulation into shoots vs exposure to Hg alone, which was congruent with the level of expression of several transporter genes, as well as the UV effect on Hg bioavailability in water. The findings of the present work underlined the importance of performing experimentation under environmentally realistic conditions and to consider the interplay between contaminants and environmental variables such as light that might have confounding effects to better understand and anticipate the effects of multiple stressors in aquatic environment. Copyright © 2016 Elsevier B.V. All rights reserved.

Capability of LOFT vital batteries to supply emergency power demands during severe cold weather conditions

International Nuclear Information System (INIS)

Yeates, J.A.

1978-01-01

This study evaluates the capability of the vital batteries (PPS) to provide electrical power via the vital DC-AC motor generator sets to the LOFT PPS loads during severe cold weather conditions. It is concluded that these batteries while at a temperature of 5 0 F will supply the necessary PPS electrical loads for a time in excess of the one hour permitted to start the diesel generators and are, therefore, adequate at this temperature. This Revision B of the LTR includes revised, more recent, and complete technical data relating to MG set efficiency, battery operating procedures and cold temperature derating. Revision B supersedes and replaces all previous issues

A systematic review of secondhand smoke exposure in a car: Attributable changes in atmospheric and biological markers.

Science.gov (United States)

Raoof, Sana A; Agaku, Israel T; Vardavas, Constantine I

2015-05-01

Exposure to secondhand smoke (SHS) has been linked to disease, disability, and premature death. While several countries have enacted smoke-free legislations, exposure to SHS may still occur in unregulated private environments, such as in the family car. We performed a systematic review of peer-reviewed literature in PubMed and Web of Science up to May 2013. Articles were selected if they provided a quantitative measure of SHS exposure (biological or atmospheric markers); the study was conducted inside a car; and the assessed exposure was attributable to cigarette combustion. From 202 articles identified, 12 met the inclusion criteria. Among all studies that assessed smoking in cars with at least one window partially open, the particulate matter 2.5 μm or less in diameter (PM2.5) concentrations ranged from 47 μg/m(3) to 12,150 μg/m(3). For studies with all windows closed, PM2.5 ranged from 203.6 μg/m(3) to 13,150 μg/m(3). SHS concentration in a car was mediated by air-conditioning status, extent of airflow, and driving speed. Smoking in cars leads to extremely high exposure to SHS and increased concentration of atmospheric markers of exposure-even in the presence of air-conditioning or increased airflow from open windows. This clearly shows that the only way to protect nonsmokers, especially children, from SHS within cars is by eliminating tobacco smoking. © The Author(s) 2015.

Impacts of Sublethal Mercury Exposure on Birds: A Detailed Review.

Science.gov (United States)

Whitney, Margaret C; Cristol, Daniel A

Mercury is a ubiquitous environmental contaminant known to accumulate in, and negatively affect, fish-eating and oceanic bird species, and recently demonstrated to impact some terrestrial songbirds to a comparable extent. It can bioaccumulate to concentrations of >1 μg/g in tissues of prey organisms such as fish and insects. At high enough concentrations, exposure to mercury is lethal to birds. However, environmental exposures are usually far below the lethal concentrations established by dosing studies.The objective of this review is to better understand the effects of sublethal exposure to mercury in birds. We restricted our survey of the literature to studies with at least some exposures >5 μg/g. The majority of sublethal effects were subtle and some studies of similar endpoints reached different conclusions. Strong support exists in the literature for the conclusion that mercury exposure reduces reproductive output, compromises immune function, and causes avoidance of high-energy behaviors. For some endpoints, notably certain measures of reproductive success, endocrine and neurological function, and body condition, there is weak or contradictory evidence of adverse effects and further study is required. There was no evidence that environmentally relevant mercury exposure affects longevity, but several of the sublethal effects identified likely do result in fitness reductions that could adversely impact populations. Overall, 72% of field studies and 91% of laboratory studies found evidence of deleterious effects of mercury on some endpoint, and thus we can conclude that mercury is harmful to birds, and the many effects on reproduction indicate that bird population declines may already be resulting from environmental mercury pollution.

Relationship between medical exposure and acquisition conditions during X-ray diagnosis of small children to reduce exposure doses in Aomori Prefecture. An analysis questionnaire

International Nuclear Information System (INIS)

Kon, Masanori; Fukushi, Shouji; Oota, Fumio; Kawamura, Kouji; Shinohe, Tetsuo; Suwa, Kouki; Fujii, Kiyosuke; Yamagami, Hirofumi

2000-01-01

A questionnaire survey to determine the exposure dose of each site imaged was performed by the Aomori Association of Radiological Technologists in September 1998. Based on the results, the relation between the entrance surface dose and loading factor and film/screen system during chest and hip joint imaging of children was analyzed, and reduction of the exposure dose was assessed. The entrance surface dose was calculated by a non-dosimeter dosimetry (NDD) method. A slight correlation was observed between tube voltage and the product of tube current x imaging time for chest imaging, but not for hip joint imaging. No correlation was observed between the entrance surface dose and tube current x imaging time for chest imaging, but a positive correlation was observed for hip joint imaging. The rates at which an inverter device, a three-phase device, and a single-phase device were used as the high-voltage generator for chest imaging were 57.5%, 30.0%, 12.5%, respectively, and 57.0%, 26.0%, and 17.0%, respectively, for hip joint imaging. The tube voltage ranged from 45 to 130 kV (mean: 70-80 kV) for chest imaging, and from 45 to 74 kV (mean: 60 kV) for hip joint imaging. The tube current ranged from 100 to 800 mA (mean: 300 mA) for chest imaging, and from 50 to 650 mA (mean: 200 mA) for hip joint imaging. The mean entrance surface dose for chest imaging was smaller (1/3-1/5) than for hip joint imaging. The maximal difference in entrance surface dose between facilities was 39.0 times, the minimal difference was 18.4 times, and the difference was less than half of the difference in adults. The rates at which photosensitive materials were used was 8% blue luminescence 8%, green luminescence 76%. Many facilities used photosensitive materials whose the relative sensitivity was approximately 250. It was concluded that reduction of the exposure doses during imaging of children had been thoroughly considered at each facility. Dose reduction was concluded to be possible by using