DECLINE AND EXTINCTION OF LAKE TROUT IN THE GREAT LAKES: CAN BIOLOGICAL INDICATORS HELP DIAGNOSE CAUSES, IDENTIFY REMEDIAL ACTIONS, AND PREDICT FUTURE CONDITIONS?

Science.gov (United States)

The lake trout, Salvelinus namaycush, is the predominant top predator native fish species of the Great Lakes. Lake trout are valued for commercial and recreational use in addition to their ecological importance. In the last half of the 20th century, population declines lead to vi...

Recent changes in the deep-water fish populations of Lake Michigan

Science.gov (United States)

Moffett, James W.

1957-01-01

The deep-water fish fauna of Lake Michigan consisted of lake trout (Salvelinus namaycush), burbot (Lota lota maculosa), seven species of chubs or deep-water ciscoes (Leucichthys spp.), and the deep-water sculpin (Myoxocephalus quadricornis). Other species occupied the deep-water zone but were not typically part of the fauna.

Bilan des introductions de salmonidés dans les lacs et ruisseaux d'altitude des Hautes-Pyrénées

Directory of Open Access Journals (Sweden)

DELACOSTE M.

1997-01-01

Full Text Available Les introductions de Salmonidés ont été importantes au cours des 60 dernières années dans les lacs et ruisseaux d'altitude des Hautes-Pyrénées. Six espèces de Salmonidés ont été introduites dans des milieux qui, pour la plupart, étaient vierges de populations piscicoles : la truite commune (Salmo trutta L., la truite arc-en-ciel (Oncorhynchus mykiss Walbaum, l'omble de fontaine (Salvelinus fontinalis Mitchill, l'omble chevalier (Salvelinus alpinus L., le cristivomer (Salvelinus namaycush Walbaum et le splake (Salvelinus fontinalis x Salvelinus namaycush. Dans de très nombreux cas, ces introductions ont abouti à des acclimatations. En revanche, les naturalisations sont beaucoup plus rares. Seules les espèces lacustres (cristivomer et omble chevalier se sont naturalisées dans la majorité des lacs où elles ont été introduites. Les conditions de reproduction constituent le facteur clé permettant d'expliquer la naturalisation des espèces. En ruisseau, il faut y ajouter la compétition avec l'espèce indigène (la truite commune, la pression halieutique ainsi que les conditions hivernales très rigoureuses. Les incidences écologiques des introductions sur les populations de truites communes indigènes sont faibles. En revanche, elles ne sont pas négligeables pour les populations de batraciens. Cette politique d'introduction a largement participé au développement de l'halieutisme dans ces milieux d'altitude. En cela, les introductions ont parfaitement répondu aux objectifs halieutiques qu'on leur avait fixés. L'acquisition de connaissances sur l'ensemble de la chaîne pyrénéenne constitue aujourd'hui une étape incontournable pour une politique de gestion globale des introductions.

Genome Sequences of Shewanella baltica and Shewanella morhuae Strains Isolated from the Gastrointestinal Tract of Freshwater Fish.

Science.gov (United States)

Castillo, Daniel; Gram, Lone; Dailey, Frank E

2018-06-21

We present here the genome sequences of Shewanella baltica strain CW2 and Shewanella morhuae strain CW7, isolated from the gastrointestinal tract of Salvelinus namaycush (lean lake trout) and Coregonus clupeaformis (whitefish), respectively. These genome sequences provide insights into the niche adaptation of these specific species in freshwater systems. Copyright © 2018 Castillo et al.

Species succession and sustainability of the Great Lakes fish community

Science.gov (United States)

Eshenroder, Randy L.; Burnham-Curtis, Mary K.; Taylor, William W.; Ferreri, C. Paola

1999-01-01

This article concentrates on the sustainability of the offshore pelagic and deepwater fish communities that were historically dominated by lake trout (Salvelinus namaycush). The causes of alteration in these fish communities (i.e., overfishing, introductions, and cultural eutrophication) were identified by Loftus and Regier (1972). Here we look at the ecology of these altered communities in relation to sustainability and discuss the need for restoration.

Polychlorinated biphenyl reduction in lake trout by irradiation and broiling

International Nuclear Information System (INIS)

Cichy, R.F.; Zabik, M.E.; Weaver, C.M.

1979-01-01

The Great Lakes Environmental contaminants surveys (1974-1975) have concluded that excessive concentrations of polychlorinated biphenyls (PCBs) are present in a specific species of lake trout (Salvelinus namaycush). Over 30 ppM of PCBs have been detected in the edible fillet of this fat trout. The objective of this study was to determine the effect of gamma irradiation combined with broiling on the levels of PCBs in lake trout fillets

First evidence of successful natural reproduction by planted lake trout in Lake Huron

Science.gov (United States)

Nester, Robert T.; Poe, Thomas P.

1984-01-01

Twenty-two lake trout (Salvelinus namaycush) swim-up fry, 24-27 mm long, were captured with emergent fry traps and a tow net in northwestern Lake Huron on a small nearshore reef off Alpena, Michigan, between May 10 and June 1, 1982. These catches represent the first evidence of successful production of swim-up fry by planted, hatchery-reared lake trout in Lake Huron since the lake trout rehabilitation program began in 1973.

Preference and avoidance pH of brook trout Salvelinus fontinalis and brown trout Salmo trutta exposed to different holding pH.

Science.gov (United States)

Fost, B A; Ferreri, C P

2015-08-01

The goal of this study was to determine if short-term exposure of brook trout Salvelinus fontinalis and brown trout Salmo trutta to a lower pH than found in their source stream results in a shift in preference or avoidance pH. The lack of a shift in preference or avoidance pH of adult S. fontinalis and S. trutta suggests that these species can be held at a pH different from the source waterbody for a short period of time without altering preference or avoidance pH behaviour. © 2015 The Fisheries Society of the British Isles.

The reproduction of lake trout in southern Lake Superior

Science.gov (United States)

Eschmeyer, Paul H.

1955-01-01

The principal spawning grounds of lake trout (Salvelinus namaycush namaycush) in United States waters of southern Lake Superior are on rocky shoals at depths of less than 20 fathoms. Most spawning occurs in October and early November. Of the mature fish collected on or near the spawning grounds, 60 to 69 percent were males. Among mature fish the average length of females was greater than that of males; few males less than 24 inches or females less than 26 inches in total length were caught. Recoveries of lake trout tagged on the spawning grounds showed that some males remained in the immediate area for a period of several weeks during the spawning season. Marked fish showed a tendency to return during later years to spawning grounds on which they had been tagged, even though many of them ranged long distances between spawning seasons.

Using Linkage Maps as a Tool To Determine Patterns of Chromosome Synteny in the Genus Salvelinus

Directory of Open Access Journals (Sweden)

Matthew C. Hale

2017-11-01

Full Text Available Next generation sequencing techniques have revolutionized the collection of genome and transcriptome data from nonmodel organisms. This manuscript details the application of restriction site-associated DNA sequencing (RADseq to generate a marker-dense genetic map for Brook Trout (Salvelinus fontinalis. The consensus map was constructed from three full-sib families totaling 176 F1 individuals. The map consisted of 42 linkage groups with a total female map size of 2502.5 cM, and a total male map size of 1863.8 cM. Synteny was confirmed with Atlantic Salmon for 38 linkage groups, with Rainbow Trout for 37 linkage groups, Arctic Char for 36 linkage groups, and with a previously published Brook Trout linkage map for 39 linkage groups. Comparative mapping confirmed the presence of 8 metacentric and 34 acrocentric chromosomes in Brook Trout. Six metacentric chromosomes seem to be conserved with Arctic Char suggesting there have been at least two species-specific fusion and fission events within the genus Salvelinus. In addition, the sex marker (sdY; sexually dimorphic on the Y chromosome was mapped to Brook Trout BC35, which is homologous with Atlantic Salmon Ssa09qa, Rainbow Trout Omy25, and Arctic Char AC04q. Ultimately, this linkage map will be a useful resource for studies on the genome organization of Salvelinus, and facilitates comparisons of the Salvelinus genome with Salmo and Oncorhynchus.

Pressure shock triploidization of Salmo trutta f. lacustris and Salvelinus umbla eggs and its impact on fish development.

Science.gov (United States)

Lahnsteiner, Franz; Kletzl, Manfred

2018-07-15

The study tested the efficiency of hydrostatic pressure triploidization methods for Salmo trutta f. lacustris and Salvelinus umbla and investigated the effects on survival rate, skeletal malformation, and on morphometrics and cellular composition of gills, spleen, liver, kidney, intestine, and blood. In Salmo trutta f. lacustris a 100% triploidy rate in combination with high larvae survival rate (80% in comparison to control) was obtained when treating eggs with a pressure of 66 × 10 3  kPa 360 °C temperature minutes (CTM) post fertilization for 5 min, in Salvelinus umbla with a similar pressure after 270 CTM. Juvenile triploid Salmo trutta f. lacustris and Salvelinus umbla (145 days post hatch) had neither an increased rate of mortality, nor an increased rate of malformations. In triploid Salmo trutta f. lacustris and Salvelinus umbla the erythrocyte volume was 50% higher and the erythrocyte concentration in peripheral blood 25-35% lower relative to diploids. In triploids also the erythrocytes surface area: volume ratio was reduced. Gills of triploid Salmo trutta f. lacustris and Salvelinus umbla had increased width of primary lamellae and increased length of secondary lamellae which might compensate for unfavorable erythrocytes surface area: volume ratio. Length of the digestive tract and histology of kidney, liver, spleen, and gills were only investigated in Salmo trutta f. lacustris. In triploids the hematopoietic tissue of the kidney was decreased by 12%, the spleen index by 53%, and the erythroblast concentrations of the spleen by 42% relative to diploids, possibly indicating reduced erythropoiesis. Length of the digestive tract and cellular arrangement of intestine, liver, and gills were not affected. In summary, the used triploidization procedure seems a reliable method not counteracting the principles of animal welfare. Copyright © 2018 Elsevier Inc. All rights reserved.

Characterization of a Neochlamydia-like Bacterium Associated with Epitheliocystis in Cultured Artic Char Salvelinus alpinus

Science.gov (United States)

Infections of branchial epithelium by intracellular gram-negative bacteria, termed epitheliocystis, have limited culture of Arctic char (Salvelinus alpinus). To characterize a bacterium associated with epitheliocystis in cultured char, gills were sampled for histopathologic examination, conventional...

Climate change and vulnerability of bull trout (Salvelinus confluentus ) in a fire-prone landscape

Science.gov (United States)

Jeffrey A. Falke; Rebecca L. Flitcroft; Jason B. Dunham; Kristina M. McNyset; Paul F. Hessburg; Gordon H. Reeves; C. Tara Marshall

2015-01-01

Linked atmospheric and wildfire changes will complicate future management of native coldwater fishes in fire-prone landscapes, and new approaches to management that incorporate uncertainty are needed to address this challenge. We used a Bayesian network (BN) approach to evaluate population vulnerability of bull trout (Salvelinus confluentus) in the Wenatchee River...

In vitro immune functions in thiamine-replete and -depleted lake trout (Salvelinus namaycush)

Science.gov (United States)

Ottinger, Christopher A.; Honeyfield, Dale C.; Densmore, Christine L.; Iwanowicz, Luke R.

2014-01-01

In this study we examined the impacts of in vivo thiamine deficiency on lake trout leukocyte function measured in vitro. When compared outside the context of individual-specific thiamine concentrations no significant differences were observed in leukocyte bactericidal activity or in concanavalin A (Con A), and phytohemagglutinin-P (PHA-P) stimulated leukocyte proliferation. Placing immune functions into context with the ratio of in vivo liver thiamine monophosphate (TMP – biologically inactive form) to thiamine pyrophosphate (TPP – biologically active form) proved to be the best indicator of thiamine depletion impacts as determined using regression modeling. These observed relationships indicated differential effects on the immune measures with bactericidal activity exhibiting an inverse relationship with TMP to TPP ratios, Con A stimulated mitogenesis exhibiting a positive relationship with TMP to TPP ratios and PHA-P stimulated mitogenesis exhibiting no significant relationships. In addition, these relationships showed considerable complexity which included the consistent observation of a thiamine-replete subgroup with characteristics similar to those seen in the leukocytes from thiamine-depleted fish. When considered together, our observations indicate that lake trout leukocytes experience cell-type specific impacts as well as an altered physiologic environment when confronted with a thiamine-limited state.

In vitro immune functions in thiamine-replete and -depleted lake trout (Salvelinus namaycush).

Science.gov (United States)

Ottinger, Christopher A; Honeyfield, Dale C; Densmore, Christine L; Iwanowicz, Luke R

2014-05-01

In this study we examined the impacts of in vivo thiamine deficiency on lake trout leukocyte function measured in vitro. When compared outside the context of individual-specific thiamine concentrations no significant differences were observed in leukocyte bactericidal activity or in concanavalin A (Con A), and phytohemagglutinin-P (PHA-P) stimulated leukocyte proliferation. Placing immune functions into context with the ratio of in vivo liver thiamine monophosphate (TMP--biologically inactive form) to thiamine pyrophosphate (TPP--biologically active form) proved to be the best indicator of thiamine depletion impacts as determined using regression modeling. These observed relationships indicated differential effects on the immune measures with bactericidal activity exhibiting an inverse relationship with TMP to TPP ratios, Con A stimulated mitogenesis exhibiting a positive relationship with TMP to TPP ratios and PHA-P stimulated mitogenesis exhibiting no significant relationships. In addition, these relationships showed considerable complexity which included the consistent observation of a thiamine-replete subgroup with characteristics similar to those seen in the leukocytes from thiamine-depleted fish. When considered together, our observations indicate that lake trout leukocytes experience cell-type specific impacts as well as an altered physiologic environment when confronted with a thiamine-limited state. Published by Elsevier Ltd.

Behavioral evidence for a role of chemoreception during reproduction in lake trout

Science.gov (United States)

Buchinger, Tyler J.; Li, Weiming; Johnson, Nicholas

2015-01-01

Chemoreception is hypothesized to influence spawning site selection, mate search, and synchronization of gamete release in chars (Salvelinus spp.), but behavioral evidence is generally lacking. Here, we provide a survey of the behavioral responses of reproductive male and female lake trout (Salvelinus namaycush) to natural conspecific chemosensory stimuli. A flow-through laboratory assay with side-by-side artificial spawning reefs was used to evaluate behavioral preferences of spawning-phase males and females for chemosensory stimuli from juveniles and from spawning-phase males and females. Males and females preferred male and juvenile stimuli over no stimuli, but only had weak preferences for female stimuli. Only females had a preference for male over juvenile stimuli when given a direct choice between the two. The unexpected observation of male attraction to male stimuli, even when offered female stimuli, indicates a fundamental difference from the existing models of chemical communication in fishes. We discuss our results from the perspectives of prespawning aggregation, mate evaluation, and spawning synchronization. Identification of specific components of the stimuli will allow confirmation of the function and may have management implications for native and invasive populations of lake trout that are ecologically and economically important.

Differences in detection of Aeromonas salmonicida in covertly infected salmonid fishes by the stress-inducible furunculosis test and culture-based assays

Science.gov (United States)

Cipriano, R.C.; Ford, L.A.; Smith, D.R.; Schachte, J.H.; Petrie, C.J.

1997-01-01

Accurate detection of Aeromonas salmonicida subsp. salmonicida (the cause of furunculosis disease) in covertly infected salmonids is difficult and is a cause of concern for those involved in fish health inspection and resource management programs. In this study, we examined populations of brook trout Salvelinus fontinalis, Atlantic salmon Salmo salar, and lake trout Salvelinus namaycush that previously sustained natural episodes of furunculosis. Consequently, the sampled fish were presumed to harbor latent infections. Mucus, gill, liver, kidney, heart, spleen, and intestine samples (N = 100 fish per group sampled) were processed and examined by (1) direct dilution counts and (2) quadrant streaking after a 48-h pre-enrichment in trypticase soy broth (TSB). Another subsample of fish from each group was then subjected to stress-inducible furunculosis tests. Stress tests detected A. salmonicida in three of four groups of fish that were examined whereas the pathogen was detected in only two of the groups analyzed with culture-based assays. Although pre-enrichment in TSB enhanced detection within internal sampling sites including the liver, heart, spleen, and kidney, enrichment did not enhance detection from mucus, gill, or intestinal samples.

Draft Genome Sequence of a Picorna-Like Virus Associated with Gill Tissue in Clinically Normal Brook Trout, Salvelinus fontinalis

OpenAIRE

Iwanowicz, Luke R.; Iwanowicz, Deborah D.; Adams, Cynthia R.; Galbraith, Heather; Aunins, Aaron; Cornman, Robert S.

2017-01-01

ABSTRACT Here, we report a draft genome sequence of a picorna-like virus associated with brook trout, Salvelinus fontinalis, gill tissue. The draft genome comprises 8,681 nucleotides, excluding the poly(A) tract, and contains two open reading frames. It is most similar to picorna-like viruses that infect invertebrates.

Draft Genome Sequence of a Picorna-Like Virus Associated with Gill Tissue in Clinically Normal Brook Trout, Salvelinus fontinalis.

Science.gov (United States)

Iwanowicz, Luke R; Iwanowicz, Deborah D; Adams, Cynthia R; Galbraith, Heather; Aunins, Aaron; Cornman, Robert S

2017-10-12

Here, we report a draft genome sequence of a picorna-like virus associated with brook trout, Salvelinus fontinalis , gill tissue. The draft genome comprises 8,681 nucleotides, excluding the poly(A) tract, and contains two open reading frames. It is most similar to picorna-like viruses that infect invertebrates.

Radio-transmitted electromyogram signals as indicators of swimming speed in lake trout and brown trout

DEFF Research Database (Denmark)

Thorstad, E.B.; Økland, F.; Koed, Anders

2000-01-01

Swimming speed and average electromyogram (EMG) pulse intervals were highly correlated in individual lake trout Salvelinus namaycush (r(2)=0.52-0.89) and brown trout Salmo trutta (r(2)=0.45-0.96). High correlations were found also for pooled data in both lake trout (r(2)=0.90) and brown trout...... of the Ema stock (r(2)=0.96) and Laerdal stock (r(2)=0.96). The linear relationship between swimming speed and average EMG pulse intervals differed significantly among lake trout and the brown trout stocks. This successful calibration of EMGs to swimming speed opens the possibility of recording swimming...... speed of free swimming lake trout and brown trout in situ. EMGs can also be calibrated to oxygen consumption to record energy expenditure. (C) 2000 The Fisheries Society of the British Isles...

Visual observations of historical lake trout spawning grounds in western Lake Huron

Science.gov (United States)

Nester, Robert T.; Poe, Thomas P.

1987-01-01

Direct underwater video observations were made of the bottom substrates at 12 spawning grounds formerly used by lake trout Salvelinus namaycush in western Lake Huron to evaluate their present suitability for successful reproduction by lake trout. Nine locations examined north of Saginaw Bay in the northwestern end of the lake are thought to provide the best spawning habitat. The substrate at these sites consisted of angular rough cobble and rubble with relatively deep interstitial spaces (a?Y 0.5 m), small amounts of fine sediments, and little or no periphytic growth. Conditions at the three other sampling locations south of Saginaw Bay seemed much less suitable for successful reproduction based on the reduced area of high-quality substrate, shallow interstitial spaces, high infiltration of fine sediments, and greater periphytic growth.

Fish resource data from the Snare River, Northwest Territories

International Nuclear Information System (INIS)

Jessop, E.F.; Chang-Kue, K.T.J.; MacDonald, G.

1994-01-01

An extensive fish sampling and tagging program was conducted on the Snare River, Northwest Territories, in order to collect baseline data on the fish populations in sections of the river altered by hydroelectric projects. Fish populations were sampled from May to July 1977 in five sections of the river that were influenced by development of hydropower at three dams currently on line; 530 tagged fish were also released. The biweekly catch composition in experimental gill nets for each study area and the catch per gill net mesh size are presented for walleye (Stizostedion vitreum), lake trout (Salvelinus namaycush), lake whitefish (Coregonus clupeaformis), lake cisco (Coregonus artedi), northern pike (Esox lucius), white sucker (Catostomus commersoni), and longnose sucker (Catostomus catostomus). Age-specific data on length, weight, age, sex, and maturity are also included. 7 refs., 12 figs., 42 tabs

Effect of artificial sunlight on the retention of external calcein marks on lake trout

Science.gov (United States)

Honeyfield, D.C.; Kehler, T.; Fletcher, J.W.; Mohler, J.W.

2008-01-01

When choosing a fish marking technique to address fishery related questions, it is important to consider factors that affect mark retention. Calcein, a chemical marking agent, is under investigation for potential use on fish. Two laboratory trials were conducted with calcein-marked lake trout Salvelinus namaycush to determine the effect of artificial sunlight on calcein mark intensity. In trial 1, fish exposed to 18,000 lx for 7 d lost 90% or more of the calcein mark intensity (relative to the colorimetric key, mg/L) on the head, body, ventral region, and pectoral fins relative to mark intensity in fish that were maintained in darkness. In trial 2, light intensity was reduced 2.5-3.0-fold. After 7 d of light exposure, calcein mark intensity on the head was reduced by 40-45% relative to mark intensity in fish that were held in darkness; by day 14, calcein mark intensity on the head was reduced by 55-60% relative to that of dark-treated fish. No further decline was observed in light-exposed fish, and head mark intensity values did not differ among days 14, 21, and 28 for this treatment group. Of the four areas evaluated, the head and pectoral fin were more easily read using a colorimetric key than the lateral or ventral regions of the fish. The concentration of calcein spotted on filter paper to devise the colorimetric key ranged from 1 to 100 mg/L. A difference of approximately 7 mg/L in apparent calcein mark intensity means for the head region could be detected using the colorimetric key. These trials showed that calcein mark intensity on lake trout declined when fish were exposed to artificial sunlight, and the use of a colorimetric key improved the objectivity of calcein mark intensity assessment.

Chromosomal characteristics and distribution of rDNA sequences in the brook trout Salvelinus fontinalis (Mitchill, 1814).

Science.gov (United States)

Śliwińska-Jewsiewicka, A; Kuciński, M; Kirtiklis, L; Dobosz, S; Ocalewicz, K; Jankun, Malgorzata

2015-08-01

Brook trout Salvelinus fontinalis (Mitchill, 1814) chromosomes have been analyzed using conventional and molecular cytogenetic techniques enabling characteristics and chromosomal location of heterochromatin, nucleolus organizer regions (NORs), ribosomal RNA-encoding genes and telomeric DNA sequences. The C-banding and chromosome digestion with the restriction endonucleases demonstrated distribution and heterogeneity of the heterochromatin in the brook trout genome. DNA sequences of the ribosomal RNA genes, namely the nucleolus-forming 28S (major) and non-nucleolus-forming 5S (minor) rDNAs, were physically mapped using fluorescence in situ hybridization (FISH) and primed in situ labelling. The minor rDNA locus was located on the subtelo-acrocentric chromosome pair No. 9, whereas the major rDNA loci were dispersed on 14 chromosome pairs, showing a considerable inter-individual variation in the number and location. The major and minor rDNA loci were located at different chromosomes. Multichromosomal location (3-6 sites) of the NORs was demonstrated by silver nitrate (AgNO3) impregnation. All Ag-positive i.e. active NORs corresponded to the GC-rich blocks of heterochromatin. FISH with telomeric probe showed the presence of the interstitial telomeric site (ITS) adjacent to the NOR/28S rDNA site on the chromosome 11. This ITS was presumably remnant of the chromosome rearrangement(s) leading to the genomic redistribution of the rDNA sequences. Comparative analysis of the cytogenetic data among several related salmonid species confirmed huge variation in the number and the chromosomal location of rRNA gene clusters in the Salvelinus genome.

An extremely sensitive nested PCR-RFLP mitochondrial marker for detection and identification of salmonids in eDNA from water samples

Directory of Open Access Journals (Sweden)

Laura Clusa

2017-02-01

Full Text Available Background Salmonids are native from the North Hemisphere but have been introduced for aquaculture and sport fishing in the South Hemisphere and inhabit most rivers and lakes in temperate and cold regions worldwide. Five species are included in the Global Invasive Species Database: rainbow trout Oncorhynchus mykiss, Atlantic salmon Salmo salar, brown trout Salmo trutta, brook trout Salvelinus fontinalis, and lake trout Salvelinus namaycush. In contrast, other salmonids are endangered in their native settings. Methods Here we have developed a method to identify salmonid species directly from water samples, focusing on the Iberian Peninsula as a case study. We have designed nested Salmonidae-specific primers within the 16S rDNA region. From these primers and a PCR-RFLP procedure the target species can be unequivocally identified from DNA extracted from water samples. Results The method was validated in aquarium experiments and in the field with water from watersheds with known salmonid populations. Finally, the method was applied to obtain a global view of the Salmonidae community in Nalón River (north coast of Spain. Discussion This new powerful, very sensitive (identifying the species down to 10 pg DNA/ml water and economical tool can be applied for monitoring the presence of salmonids in a variety of situations, from checking upstream colonization after removal of river barriers to monitoring potential escapes from fish farms.

Toxicity of fluoride to aquatic species and evaluation of toxicity modifying factors.

Science.gov (United States)

Pearcy, Krysta; Elphick, James; Burnett-Seidel, Charlene

2015-07-01

The present study was performed to investigate the toxicity of fluoride to a variety of freshwater aquatic organisms and to establish whether water quality variables contribute substantively to modifying its toxicity. Water hardness, chloride, and alkalinity were tested as possible toxicity modifying factors for fluoride using acute toxicity tests with Hyalella azteca and Oncorhynchus mykiss. Chloride appeared to be the major toxicity modifying factor for fluoride in these acute toxicity tests. The chronic toxicity of fluoride was evaluated with a variety of species, including 3 fish (Pimephales promelas, O. mykiss, and Salvelinus namaycush), 3 invertebrates (Ceriodaphnia dubia, H. azteca, and Chironomus dilutus), 1 plant (Lemna minor), and 1 alga (Pseudokirchneriella subcapitata). Hyalella azteca was the most sensitive species overall, and O. mykiss was the most sensitive species of fish. The role of chloride as a toxicity modifying factor was inconsistent between species in the chronic toxicity tests. © 2015 SETAC.

New records of Ergasilus (Copepoda: Ergasilidae) in the Laurentian Great Lakes, including a lakewide review of records and host associations

Science.gov (United States)

Hudson, Patrick L.; Bowen, Charles A.; Stedman, Ralph M.

1994-01-01

Ergasilus nerkae was found infecting ninespine stickleback (Pungitius pungitius) in lakes Huron, Michigan, and Superior and threespine stickleback (Gasterosteus aculeatus) and round whitefish (Prosopium cylindraceum) in Lake Huron. Based upon the literature and study of archived material, we propose that E. nerkae is enzootic to the Great Lakes and that ninespine stickleback are a preferred host in Lake Huron. Prevalence of E. nerkae on ninespine stickleback increased from 17% in June to 68% in September, but mean intensity remained light. Prevalence and mean intensity increased with host length. Ergasilus luciopercarum is also reported on lake trout (Salvelinus namaycush) and largemouth bass (Micropterus salmoides) for the first time. Host-parasite records of Ergasilus spp. in North America are reviewed, biology and taxonomy are summarized, and a checklist of Great Lakes host-parasite-locality records is provided. At present, eight species of Ergasilus are known to infect 42 Great Lakes fish species.

Temperature, pressure and light data collected by attached Archival Transmitting Tags to Salvelinus malma (Dolly Varden trout) in the Wulik River, Alaska, during 2012-06 to 2013-10 (NODC Accession 0119954)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains data collected by electronic tags (Pop-up Satellite Archival Transmitting) attached to Salvelinus malma (Dolly Varden trout) in the Wulik...

Dwarf char, a new form of chars (the genus Salvelinus) in Lake Kronotskoe

Science.gov (United States)

Pavlov, S.D.; Pivovarov, E.A.; Ostberg, C.O.

2012-01-01

Lake Kronotskoe is situated in the Kronotskii State Nature Reserve and is a unique natural heritage of Kamchatka. The lake–river system of the reserve includes numerous springs and small streams and three large inflowing rivers, Listvennichnaya, Unana, and Uzon, which form the main bays of Lake Kronotskoe; one river (Kronotskaya) flows from the lake. This river is characterized by several rapids, which are assumed to be unsurmountable barriers for fish migration. The ichthyofauna of the lake has been isolated for a long time, and some endemic fishes appeared, including char of the genus Salvelinus and the residential form of red salmon Oncorhynchus nerka (the local name is kokanee). These species are perfect model objects to study microevolution processes. Char of Lake Kronotskoe are characterized by significant polymorphism and plasticity [1–3]; therefore, they are extremely valuable for studying the processes of speciation and form development. That is why the populations of char in Lake Kronotskoe are unique and attract special attention of researchers. 

Effects of dressing and cooking on DDT concentrations in certain fish from Lake Michigan

Science.gov (United States)

Reinert, Robert E.; Stewart, Donald; Seagran, Harry L.

1972-01-01

Concentrations of DDT residues were highest in parts of the body with the highest oil content in four species of fish from Lake Michigan: yellow perch (Perca flavescens), bloater (Coregonus hoyi), lake trout (Salvelinus namaycush), and coho salmon (Oncorhynchus kisutch). Dressing reduced the DDT residues and oil content by more than 90% in yellow perch but had little effect in the other three species. The concentration of DDT residues in bloaters was changed little by smoking but was reduced 64–72% by other methods of cooking: from 8.0 ppm (raw) to 2.2 ppm after frying in corn oil; from 10.7 to 3.9 ppm after frying in lard; and from 9.1 to 3.2 ppm after broiling. The concentration of DDT residues in fillets of yellow perch changed only from 0.3 ppm (raw) to 0.4 or 0.5 ppm after baking, frying, or broiling.

Lake trout otolith chronologies as multidecadal indicators of high-latitude freshwater ecosystems

Science.gov (United States)

Black, B.A.; Von Biela, V.R.; Zimmerman, C.E.; Brown, Randy J.

2013-01-01

High-latitude ecosystems are among the most vulnerable to long-term climate change, yet continuous, multidecadal indicators by which to gauge effects on biology are scarce, especially in freshwater environments. To address this issue, dendrochronology (tree-ring analysis) techniques were applied to growth-increment widths in otoliths from lake trout (Salvelinus namaycush) from the Chandler Lake system, Alaska (68.23°N, 152.70°W). All otoliths were collected in 1987 and exhibited highly synchronous patterns in growth-increment width. Increments were dated, the widths were measured, and age-related growth declines were removed using standard dendrochronology techniques. The detrended time series were averaged to generate an annually resolved chronology, which continuously spanned 1964–1984. The chronology positively and linearly correlated with August air temperature over the 22-year interval (p otolith chronologies could be used to examine responses between freshwater ecosystems and environmental variability across a range of temporal and spatial scales.

17beta-estradiol induced vitellogenesis is inhibited by cortisol at the post-transcriptional level in Arctic char (Salvelinus alpinus

Directory of Open Access Journals (Sweden)

Modig Carina

2004-09-01

Full Text Available Abstract This study was performed to investigate stress effects on the synthesis of egg yolk precursor, vitellogenin (Vtg in Arctic char (Salvelinus alpinus. In particular the effect of cortisol (F was determined since this stress hormone has been suggested to interfere with vitellogenesis and is upregulated during sexual maturation in teleosts. Arctic char Vtg was purified and polyclonal antibodies were produced in order to develop tools to study regulation of vitellogenesis. The Vtg antibodies were used to develop an enzyme-linked immunosorbent assay. The corresponding Vtg cDNA was cloned from a hepatic cDNA library in order to obtain DNA probes to measure Vtg mRNA expression. Analysis of plasma from juvenile Arctic char, of both sexes, exposed to different steroids showed that production of Vtg was induced in a dose dependent fashion by 17β-estradiol (E2, estrone and estriol. Apart from estrogens a high dose of F also upregulated Vtg. In addition, F, progesterone (P and tamoxifen were tested to determine these compounds ability to modulate E2 induced Vtg synthesis at both the mRNA and protein level. Tamoxifen was found to inhibit E2 induced Vtg mRNA and protein upregulation. P did not alter the Vtg induction while F reduced the Vtg protein levels without affecting the Vtg mRNA levels. Furthermore the inhibition of Vtg protein was found to be dose dependent. Thus, the inhibitory effect of F on Vtg appears to be mediated at the post-transcriptional level.

Biotransformation of polychlorinated biphenyls (PCBs) and bioformation of hydroxylated PCBs in fish

Energy Technology Data Exchange (ETDEWEB)

Buckman, Andrea H. [Department of Environmental Biology, University of Guelph, Guelph, Ont., N1G 2W1 (Canada); National Waters Research Institute, Environment Canada, Burlington, Ont., Canada L7R 4A6 (Canada); Wong, Charles S. [Department of Chemistry, University of Alberta, Edmonton, Alta. (Canada); Chow, Elaine A. [Department of Chemistry, University of Alberta, Edmonton, Alta. (Canada); Brown, Scott B. [National Waters Research Institute, Environment Canada, Burlington, Ont., L7R 4A6 (Canada); Solomon, Keith R. [Department of Environmental Biology, University of Guelph, Guelph, Ont., N1G 2W1 (Canada); Fisk, Aaron T. [Warnell School of Forest Resources, University of Georgia, Athens, GA 30602-2152 (United States)]. E-mail: afisk@smokey.forestry.uga.edu

2006-06-15

Hydroxylated PCBs (OH-PCBs) are a class of organic contaminants that have been found recently in the plasma of Great Lakes fish, the source of which is either bioformation from PCBs or accumulation from the environment. To address the potential for fish to biotransform PCBs and bioform OH-PCBs juvenile rainbow trout (Oncorhynchus mykiss; {approx}80 g) were exposed to dietary concentrations of an environmentally relevant mixture of PCBs. Eight OH-PCBs were found in the plasma of rainbow trout after 30 days of exposure to the PCBs, the relative pattern of which was similar to those observed in wild lake trout (Salvelinus namaycush) from Lake Ontario. Hydroxylated-PCBs were not found (detection limit 0.02 pg/g) in the food or control (not PCB-exposed) fish. A curvilinear log t {sub 1/2}-log K {sub ow} relationship for recalcitrant PCBs was found, similar to previously reported relationships, although t {sub 1/2} values were longer and shorter than studies using smaller fish or cooler temperatures, respectively. A number of PCB congeners fell below the log t {sub 1/2}-log K {sub ow} relationship providing the first estimates of non-chiral PCB biotransformation rates in fish. Enantioselective degradation of the chiral congeners PCBs 91 and 136, also indicated biotransformation. Biotransformation of PCBs was structure-dependent with greater biotransformation of PCBs with vicinal hydrogen atoms in the meta/para positions, suggesting CYP 2B-like biotransformation. Other chiral congeners with a meta/para substitution pattern showed no enantioselective degradation but were biotransformed based on the log t {sub 1/2}-log K {sub ow} relationship. The results of this study demonstrate that laboratory held rainbow trout can biotransform a number of PCB congeners and that bioformation is likely an important source of OH-PCBs in wild salmonids of the Great Lakes.

Biotransformation of polychlorinated biphenyls (PCBs) and bioformation of hydroxylated PCBs in fish

International Nuclear Information System (INIS)

Buckman, Andrea H.; Wong, Charles S.; Chow, Elaine A.; Brown, Scott B.; Solomon, Keith R.; Fisk, Aaron T.

2006-01-01

Hydroxylated PCBs (OH-PCBs) are a class of organic contaminants that have been found recently in the plasma of Great Lakes fish, the source of which is either bioformation from PCBs or accumulation from the environment. To address the potential for fish to biotransform PCBs and bioform OH-PCBs juvenile rainbow trout (Oncorhynchus mykiss; ∼80 g) were exposed to dietary concentrations of an environmentally relevant mixture of PCBs. Eight OH-PCBs were found in the plasma of rainbow trout after 30 days of exposure to the PCBs, the relative pattern of which was similar to those observed in wild lake trout (Salvelinus namaycush) from Lake Ontario. Hydroxylated-PCBs were not found (detection limit 0.02 pg/g) in the food or control (not PCB-exposed) fish. A curvilinear log t 1/2 -log K ow relationship for recalcitrant PCBs was found, similar to previously reported relationships, although t 1/2 values were longer and shorter than studies using smaller fish or cooler temperatures, respectively. A number of PCB congeners fell below the log t 1/2 -log K ow relationship providing the first estimates of non-chiral PCB biotransformation rates in fish. Enantioselective degradation of the chiral congeners PCBs 91 and 136, also indicated biotransformation. Biotransformation of PCBs was structure-dependent with greater biotransformation of PCBs with vicinal hydrogen atoms in the meta/para positions, suggesting CYP 2B-like biotransformation. Other chiral congeners with a meta/para substitution pattern showed no enantioselective degradation but were biotransformed based on the log t 1/2 -log K ow relationship. The results of this study demonstrate that laboratory held rainbow trout can biotransform a number of PCB congeners and that bioformation is likely an important source of OH-PCBs in wild salmonids of the Great Lakes

Use of wild trout for PBDE assessment in freshwater environments: Review and summary of critical factors

Directory of Open Access Journals (Sweden)

Juan M. Ríos

2015-11-01

Full Text Available Certain wild animals represent sentinels to address issues related to environmental pollution, since they can provide integrative data on both pollutant exposure and biological effects. Despite their technological benefits, PBDEs are considered a threat to environmental health due to their persistence, toxicity, and capacity to be accumulated. These pollutants have been found geographically widespread in fish, particularly in predator species such as trout. The aim of this work is to critically review the applicability and usefulness of wild trout for assessing PBDEs in freshwater environments. Reviewed reports include data from highly industrialized areas as well as areas from remote regions with relatively low human activity, including European and North American great lakes and freshwater environments in Europe, Greenland, subarctic areas and Patagonia, respectively. A summary of relevant factors were grouped into organism-specific factors (food habits, age, size, lipid content, sex and reproduction, tissue type, mechanism of contaminant uptake and metabolism, and PBDE levels in the surrounding environment (sediment. Five wild trout species [rainbow trout (Oncorhynchus mykiss, brown trout (Salmo trutta, lake trout (Salvelinus namaycush, arctic char (Salvelinus alpinus, and brook trout (Salvelinus fontinalis], collected worldwide within the 1994 to present time frame, were considered. Multivariate techniques (principal component analysis-PCA and mapping approach, showed clear differences in geographic distribution patterns of PBDE levels in trout depending on the region studied: wild trout from European and North American great lakes have the highest PBDE loads. This pattern could be due to high industrial activity at these locations. A correlational approach used to explore intraspecific relationships between PBDE levels and morphometry, showed positive relationships only for brown trout. Further, brown trout showed the highest trout

Climate change and vulnerability of bull trout (Salvelinus confluentus) in a fire-prone landscape.

Science.gov (United States)

Falke, Jeffrey A.; Flitcroft, Rebecca L; Dunham, Jason B.; McNyset, Kristina M.; Hessburg, Paul F.; Reeves, Gordon H.

2015-01-01

Linked atmospheric and wildfire changes will complicate future management of native coldwater fishes in fire-prone landscapes, and new approaches to management that incorporate uncertainty are needed to address this challenge. We used a Bayesian network (BN) approach to evaluate population vulnerability of bull trout (Salvelinus confluentus) in the Wenatchee River basin, Washington, USA, under current and future climate and fire scenarios. The BN was based on modeled estimates of wildfire, water temperature, and physical habitat prior to, and following, simulated fires throughout the basin. We found that bull trout population vulnerability depended on the extent to which climate effects can be at least partially offset by managing factors such as habitat connectivity and fire size. Moreover, our analysis showed that local management can significantly reduce the vulnerability of bull trout to climate change given appropriate management actions. Tools such as our BN that explicitly integrate the linked nature of climate and wildfire, and incorporate uncertainty in both input data and vulnerability estimates, will be vital in effective future management to conserve native coldwater fishes.

Summer temperature metrics for predicting brook trout (Salvelinus fontinalis) distribution in streams

Science.gov (United States)

Parrish, Donna; Butryn, Ryan S.; Rizzo, Donna M.

2012-01-01

We developed a methodology to predict brook trout (Salvelinus fontinalis) distribution using summer temperature metrics as predictor variables. Our analysis used long-term fish and hourly water temperature data from the Dog River, Vermont (USA). Commonly used metrics (e.g., mean, maximum, maximum 7-day maximum) tend to smooth the data so information on temperature variation is lost. Therefore, we developed a new set of metrics (called event metrics) to capture temperature variation by describing the frequency, area, duration, and magnitude of events that exceeded a user-defined temperature threshold. We used 16, 18, 20, and 22°C. We built linear discriminant models and tested and compared the event metrics against the commonly used metrics. Correct classification of the observations was 66% with event metrics and 87% with commonly used metrics. However, combined event and commonly used metrics correctly classified 92%. Of the four individual temperature thresholds, it was difficult to assess which threshold had the “best” accuracy. The 16°C threshold had slightly fewer misclassifications; however, the 20°C threshold had the fewest extreme misclassifications. Our method leveraged the volumes of existing long-term data and provided a simple, systematic, and adaptable framework for monitoring changes in fish distribution, specifically in the case of irregular, extreme temperature events.

Lake trout otolith chronologies as multidecadal indicators of high-latitude freshwater ecosystems

Science.gov (United States)

Black, B.A.; Von Biela, V.R.; Zimmerman, C.E.; Brown, Randy J.

2013-01-01

High-latitude ecosystems are among the most vulnerable to long-term climate change, yet continuous, multidecadal indicators by which to gauge effects on biology are scarce, especially in freshwater environments. To address this issue, dendrochronology (tree-ring analysis) techniques were applied to growth-increment widths in otoliths from lake trout (Salvelinus namaycush) from the Chandler Lake system, Alaska (68.23°N, 152.70°W). All otoliths were collected in 1987 and exhibited highly synchronous patterns in growth-increment width. Increments were dated, the widths were measured, and age-related growth declines were removed using standard dendrochronology techniques. The detrended time series were averaged to generate an annually resolved chronology, which continuously spanned 1964–1984. The chronology positively and linearly correlated with August air temperature over the 22-year interval (p fish metabolic rate or lake productivity. Given the broad distribution of lake trout within North America, this study suggests that otolith chronologies could be used to examine responses between freshwater ecosystems and environmental variability across a range of temporal and spatial scales.

Xenobiotic-induced apoptosis: significance and potential application as a general biomarker of response

Science.gov (United States)

Sweet, Leonard I.; Passino-Reader, Dora R.; Meier, Peter G.; Omann, Geneva M.

1999-01-01

The process of apoptosis, often coined programmed cell death, involves cell injury induced by a variety of stimuli including xenobiotics and is morphologically, biochemically, and physiologically distinct from necrosis. Apoptotic death is characterized by cellular changes such as cytoplasm shrinkage, chromatin condensation, and plasma membrane asymmetry. This form of cell suicide is appealing as a general biomarker of response in that it is expressed in multiple cell systems (e.g. immune, neuronal, hepatal, intestinal, dermal, reproductive), is conserved phylogenetically (e.g. fish, rodents, birds, sheep, amphibians, roundworms, plants, humans), is modulated by environmentally relevant levels of chemical contaminants, and indicates a state of stress of the organism. Further, apoptosis is useful as a biomarker as it serves as a molecular control point and hence may provide mechanistic information on xenobiotic stress. Studies reviewed here suggest that apoptosis is a sensitive and early indicator of acute and chronic chemical stress, loss of cellular function and structure, and organismal health. Examples are provided of the application of this methodology in studies of health of lake trout (Salvelinus namaycush) in the Laurentian Great Lakes.

Comparison of genetic and visual identification of cisco and lake whitefish larvae from Chaumont Bay, Lake Ontario

Science.gov (United States)

George, Ellen M.; Hare, Matthew P.; Crabtree, Darran L.; Lantry, Brian F.; Rudstam, Lars G.

2017-01-01

Cisco Coregonus artedi are an important component of native food webs in the Great Lakes, and their restoration is instrumental to the recovery of lake trout Salvelinus namaycush and Atlantic salmon Salmo salar. Difficulties with visual identification of larvae can confound early life history surveys, as cisco are often difficult to distinguish from lake whitefish C. clupeaformis. We compared traditional visual species identification methods to genetic identifications based on barcoding of the mitochondrial cytochrome C oxidase I gene for 726 coregonine larvae caught in Chaumont Bay, Lake Ontario. We found little agreement between the visual characteristics of cisco identified by genetic barcoding and the most widely used dichotomous key, and the considerable overlap in ranges of traditionally utilized metrics suggest that visual identification of coregonine larvae from Chaumont Bay is impractical. Coregonines are highly variable and plastic species, and often display wide variations in morphometric characteristics across their broad range. This study highlights the importance of developing accurate, geographically appropriate larval identification methods in order to best inform cisco restoration and management efforts.

Comparison of organotin accumulation on the white-spotted charr Salvelinus leucomaenis between sea-run and freshwater-resident types

Science.gov (United States)

Ohji, Madoka; Harino, Hiroya; Arai, Takaomi

2011-01-01

To examine the accumulation pattern of organotin compounds (OTs) in relation to the migration of diadromous fish, tributyltin (TBT) and triphenyltin (TPT) compounds and their derivatives were determined in the muscle tissue of both sea-run (anadromous) and freshwater-resident (nonanadromous) types of the white-spotted charr Salvelinus leucomaenis. There were generally no significant correlations between the TBT and TPT accumulation and various biological characteristics such as the total length (TL), body weight (BW), age and sex in S. leucomaenis. It is noteworthy that the TBT and TPT concentrations in sea-run white-spotted charr were significantly higher than in freshwater-resident individuals, although they are intraspecies. These results suggest that the sea-run S. leucomaenis has a higher ecological risk of TBT and TPT exposure than the freshwater-residents during their life history.

Use of the Rigor Mortis Process as a Tool for Better Understanding of Skeletal Muscle Physiology: Effect of the Ante-Mortem Stress on the Progression of Rigor Mortis in Brook Charr (Salvelinus fontinalis).

Science.gov (United States)

Diouf, Boucar; Rioux, Pierre

1999-01-01

Presents the rigor mortis process in brook charr (Salvelinus fontinalis) as a tool for better understanding skeletal muscle metabolism. Describes an activity that demonstrates how rigor mortis is related to the post-mortem decrease of muscular glycogen and ATP, how glycogen degradation produces lactic acid that lowers muscle pH, and how…

Adjustments of Protein Metabolism in Fasting Arctic Charr, Salvelinus alpinus.

Directory of Open Access Journals (Sweden)

Alicia A Cassidy

Full Text Available Protein metabolism, including the interrelated processes of synthesis and degradation, mediates the growth of an animal. In ectothermic animals, protein metabolism is responsive to changes in both biotic and abiotic conditions. This study aimed to characterise responses of protein metabolism to food deprivation that occur in the coldwater salmonid, Arctic charr, Salvelinus alpinus. We compared two groups of Arctic charr: one fed continuously and the other deprived of food for 36 days. We measured the fractional rate of protein synthesis (KS in individuals from the fed and fasted groups using a flooding dose technique modified for the use of deuterium-labelled phenylalanine. The enzyme activities of the three major protein degradation pathways (ubiquitin proteasome, lysosomal cathepsins and the calpain systems were measured in the same fish. This study is the first to measure both KS and the enzymatic activity of protein degradation in the same fish, allowing us to examine the apparent contribution of different protein degradation pathways to protein turnover in various tissues (red and white muscle, liver, heart and gills. KS was lower in the white muscle and in liver of the fasted fish compared to the fed fish. There were no observable effects of food deprivation on the protease activities in any of the tissues with the exception of liver, where the ubiquitin proteasome pathway seemed to be activated during fasting conditions. Lysosomal proteolysis appears to be the primary degradation pathway for muscle protein, while the ubiquitin proteasome pathway seems to predominate in the liver. We speculate that Arctic charr regulate protein metabolism during food deprivation to conserve proteins.

Multiscale hydrogeomorphic influences on bull trout (Salvelinus confluentus) spawning habitat

Science.gov (United States)

Bean, Jared R; Wilcox, Andrew C.; Woessner, William W.; Muhlfeld, Clint C.

2015-01-01

We investigated multiscale hydrogeomorphic influences on the distribution and abundance of bull trout (Salvelinus confluentus) spawning in snowmelt-dominated streams of the upper Flathead River basin, northwestern Montana. Within our study reaches, bull trout tended to spawn in the finest available gravel substrates. Analysis of the mobility of these substrates, based on one-dimensional hydraulic modeling and calculation of dimensionless shear stresses, indicated that bed materials in spawning reaches would be mobilized at moderate (i.e., 2-year recurrence interval) high-flow conditions, although the asynchronous timing of the fall–winter egg incubation period and typical late spring – early summer snowmelt high flows in our study area may limit susceptibility to redd scour under current hydrologic regimes. Redd occurrence also tended to be associated with concave-up bedforms (pool tailouts) with downwelling intragravel flows. Streambed temperatures tracked stream water diurnal temperature cycles to a depth of at least 25 cm, averaging 6.1–8.1 °C in different study reaches during the spawning period. Ground water provided thermal moderation of stream water for several high-density spawning reaches. Bull trout redds were more frequent in unconfined alluvial valley reaches (8.5 versus 5.0 redds·km−1 in confined valley reaches), which were strongly influenced by hyporheic and groundwater – stream water exchange. A considerable proportion of redds were patchily distributed in confined valley reaches, however, emphasizing the influence of local physical conditions in supporting bull trout spawning habitat. Moreover, narrowing or “bounding” of these alluvial valley segments did not appear to be important. Our results suggest that geomorphic, thermal, and hydrological factors influence bull trout spawning occurrence at multiple spatial scales.

Altered steroid metabolism in several teleost species exposed to endocrine disrupting substances in refuse dump leachate

NARCIS (Netherlands)

Noaksson, E.; Linderoth, M.; Bosveld, A.T.C.; Balk, L.

2003-01-01

Endocrine disruption associated with reproductive failure has been reported previously in female perch (Perca fluviatilis) and roach (Rutilus rutilus) from Lake Molnbyggen in Sweden and in female brook trout (Salvelinus fontinalis) from Vadbäcken, a stream emptying into Molnbyggen. Both Molnbyggen

Biomagnification of mercury through lake trout (Salvelinus namaycush) food webs of lakes with different physical, chemical and biological characteristics

Energy Technology Data Exchange (ETDEWEB)

Kidd, Karen A., E-mail: kiddk@unbsj.ca [Canadian Rivers Institute and Biology Department, University of New Brunswick, Saint John, NB, Canada E2L 4L5 (Canada); Muir, Derek C.G., E-mail: derek.muir@ec.gc.ca [Aquatic Contaminants Research Division, Environment Canada, Burlington, ON, Canada L7R 4A6 (Canada); Evans, Marlene S., E-mail: marlene.evans@ec.gc.ca [Aquatic Contaminants Research Division, Environment Canada, Saskatoon, SK, Canada S7N 3H5 (Canada); Wang, Xioawa, E-mail: xiaowa.wang@ec.gc.ca [Aquatic Contaminants Research Division, Environment Canada, Burlington, ON, Canada L7R 4A6 (Canada); Whittle, Mike [Aquatic Contaminants Research Division, Environment Canada, Burlington, ON, Canada L7R 4A6 (Canada); Swanson, Heidi K., E-mail: heidikswanson@yahoo.ca [Department of Biological Sciences, University of Alberta, Edmonton, AB, Canada T6G 2E9 (Canada); Johnston, Tom, E-mail: tjohnston@laurentian.ca [Cooperative Freshwater Ecology Unit, Ontario Ministry of Natural Resources, and Biology Department, Laurentian University, Sudbury, ON, Canada P3E 2C6 (Canada); Guildford, Stephanie, E-mail: sguildfo@d.umn.edu [Department of Biology and Large Lakes Observatory, University of Minnesota Duluth, 2205 5th St., Duluth, MN, 55812 (United States)

2012-11-01

Mercury (Hg) biomagnification in aquatic ecosystems remains a concern because this pollutant is known to affect the health of fish-eating wildlife and humans, and the fish themselves. The 'rate' of mercury biomagnification is being assessed more frequently using stable nitrogen isotope ratios ({delta}{sup 15}N), a measure of relative trophic position of biota within a food web. Within food webs and across diverse systems, log-transformed Hg concentrations are significantly and positively related to {delta}{sup 15}N and the slopes of these models vary from one study to another for reasons that are not yet understood. Here we compared the rates of Hg biomagnification in 14 lake trout lakes from three provinces in Canada to understand whether any characteristics of the ecosystems explained this among-system variability. Several fish species, zooplankton and benthic invertebrates were collected from these lakes and analyzed for total Hg (fish only), methyl Hg (invertebrates) and stable isotopes ({delta}{sup 15}N; {delta}{sup 13}C to assess energy sources). Mercury biomagnification rates varied significantly across systems and were higher for food webs of larger (surface area), higher nutrient lakes. However, the slopes were not predictive of among-lake differences in Hg in the lake trout. Results indicate that among-system differences in the rates of Hg biomagnification seen in the literature may be due, in part, to differences in ecosystem characteristics although the mechanisms for this variability are not yet understood. -- Highlights: Black-Right-Pointing-Pointer Mercury biomagnifies through aquatic food webs to toxic levels in top predator fishes. Black-Right-Pointing-Pointer Among-system differences in mercury transfer through food webs occur but have not been explained. Black-Right-Pointing-Pointer Diverse lakes supporting lake trout were compared to understand the ecosystem processes that affect mercury biomagnification. Black-Right-Pointing-Pointer Higher biomagnification of mercury was found in larger, higher nutrient lakes. Black-Right-Pointing-Pointer Results show that the food web processing of mercury is related to ecosystem properties.

A Quantitative Polymerase Chain Reaction Assay for the Detection and Quantification of Epizootic Epitheliotropic Disease Virus (EEDV; Salmonid Herpesvirus 3).

Science.gov (United States)

Glenney, Gavin W; Barbash, Patricia A; Coll, John A

2016-03-01

Epizootic epitheliotropic disease virus (EEDV; salmonid herpesvirus [SalHV3]; family Alloherpesviridae) causes a systemic disease of juvenile and yearling Lake Trout Salvelinus namaycush. No cell lines are currently available for the culture and propagation of EEDV, so primary diagnosis is limited to PCR and electron microscopy. To better understand the pervasiveness of EEDV (carrier or latent state of infection) in domesticated and wild Lake Trout populations, we developed a sensitive TaqMan quantitative PCR (qPCR) assay to detect the presence of the EEDV terminase gene in Lake Trout tissues. This assay was able to detect a linear standard curve over nine logs of plasmid dilution and was sensitive enough to detect single-digit copies of EEDV. The efficiency of the PCR assay was 99.4 ± 0.06% (mean ± SD), with a 95% confidence limit of 0.0296 (R(2) = 0.994). Methods were successfully applied to collect preliminary data from a number of species and water bodies in the states of Pennsylvania, New York, and Vermont, indicating that EEDV is more common in wild fish than previously known. In addition, through the development of this qPCR assay, we detected EEDV in a new salmonid species, the Cisco Coregonus artedi. The qPCR assay was unexpectedly able to detect two additional herpesviruses, the Atlantic Salmon papillomatosis virus (ASPV; SalHV4) and the Namaycush herpesvirus (NamHV; SalHV5), which both share high sequence identity with the EEDV terminase gene. With these unexpected findings, we subsequently designed three primer sets to confirm initial TaqMan qPCR assay positives and to differentiate among EEDV, ASPV, and NamHV by detecting the glycoprotein genes via SYBR Green qPCR. Received April 20, 2015; accepted November 10, 2015.

Hiding in Plain Sight: A Case for Cryptic Metapopulations in Brook Trout (Salvelinus fontinalis.

Directory of Open Access Journals (Sweden)

David C Kazyak

Full Text Available A fundamental issue in the management and conservation of biodiversity is how to define a population. Spatially contiguous fish occupying a stream network have often been considered to represent a single, homogenous population. However, they may also represent multiple discrete populations, a single population with genetic isolation-by-distance, or a metapopulation. We used microsatellite DNA and a large-scale mark-recapture study to assess population structure in a spatially contiguous sample of Brook Trout (Salvelinus fontinalis, a species of conservation concern. We found evidence for limited genetic exchange across small spatial scales and in the absence of barriers to physical movement. Mark-recapture and stationary passive integrated transponder antenna records demonstrated that fish from two tributaries very seldom moved into the opposite tributary, but movements between the tributaries and mainstem were more common. Using Bayesian genetic clustering, we identified two genetic groups that exhibited significantly different growth rates over three years of study, yet survival rates were very similar. Our study highlights the importance of considering the possibility of multiple genetically distinct populations occurring within spatially contiguous habitats, and suggests the existence of a cryptic metapopulation: a spatially continuous distribution of organisms exhibiting metapopulation-like behaviors.

Lake Ontario: Food web dynamics in a changing ecosystem (1970-2000)

Science.gov (United States)

Mills, E.L.; Casselman, J.M.; Dermott, R.; Fitzsimons, J.D.; Gal, G.; Holeck, K. T.; Hoyle, J.A.; Johannsson, O.E.; Lantry, B.F.; Makarewicz, J.C.; Millard, E.S.; Munawar, I.F.; Munawar, M.; O'Gorman, R.; Owens, R.W.; Rudstam, L. G.; Schaner, T.; Stewart, T.J.

2003-01-01

We examined stressors that have led to profound ecological changes in the Lake Ontario ecosystem and its fish community since 1970. The most notable changes have been reductions in phosphorus loading, invasion by Dreissena spp., fisheries management through stocking of exotic salmonids and control of sea lamprey (Petromyzon marinus), and fish harvest by anglers and double-crested cormorants (Phalacrocorax auritus). The response to these stressors has led to (i) declines in both algal photosynthesis and epilimnetic zooplankton production, (ii) decreases in alewife (Alosa pseudoharengus) abundance, (iii) declines in native Diporeia and lake whitefish (Coregonus clupeaformis), (iv) behavioral shifts in alewife spatial distribution benefitting native lake trout (Salvelinus namaycush), threespine stickleback (Gasterosteus aculeatus), and emerald shiner (Notropis atherinoides) populations, (v) dramatic increases in water clarity, (vi) predation impacts by cormorants on select fish species, and (vii) lake trout recruitment bottlenecks associated with alewife-induced thiamine deficiency. We expect stressor responses associated with anthropogenic forces like exotic species invasions and global climate warming to continue to impact the Lake Ontario ecosystem in the future and recommend continuous long-term ecological studies to enhance scientific understanding and management of this important resource.

Geochemical pathways and biological uptake of radium in small Canadian Shield lakes

International Nuclear Information System (INIS)

Hesslein, R.H.; Slavicek, E.

1984-01-01

The sediment-water interactions and biological uptake of 226 Ra are described for four small Canadian Shield lakes at the Experimental Lakes Area, Kenora, Ontario. A single addition of 226 Ra was made to each lake between 1970 and 1976. Approximately 90 percent of the added 226 Ra initially sorbed to the sediments. Outflow from the lakes showed losses of only 5-11 percent 226 Ra per year. Models are proposed for adsorption and outflow of 226 Ra from lakes. Biological uptake and long-term 226 Ra concentrations were measured in three species of macrophytes, crayfish, and five species of fish. Bioaccumulation ranged from 1100 to 5000 in macrophytes, 705 in crayfish, from 30 to 80 in large trout (Salvelinus namaycush), white sucker (Catostomus commersoni), and lake whitefish (Coregonus clupeaformis), and from 230 to 1200 in fathead minnows (Pimephales promelas), pearl dace (Semotilus margarita), and northern redbelly dace (Chrosomus eos). The concept of Ra/Ca ratio in organisms versus water and food is used to explain the differences in bioaccumulation. 226 Ra is discriminated against versus calcium by fish but favoured by macrophytes and crayfish

Ethyl-p-aminobenzoate (Benzocaine): efficacy as an anesthetic for five species of freshwater fish

Science.gov (United States)

Dawson, V.K.; Gilderhus, P.A.

1979-01-01

Ethyl-p-aminobenzoate (benzocaine) was tested for its efficacy as an anesthetic for rainbow trout (Salmo gairdnerii, brown trout (Salmo truttas, northern pike (Esox lucius). carp (Cyprinus carpio), and largemouth bass (Mieropterus salmoidesi. Since benzocaine is not water soluble, it was applied with acetone as a carrier. Concentrations of 100 to 200 mg!l were required for large adult northern pike, compared with 50 to 100 mg/l for small fish. Rates of sedation and recovery were slower in cold water than in warm water. Water hardness had little influence on the activity of benzocaine. Fish were anesthetized faster and recovered more slowly in acid than in alkaline water. Benzocaine produced deep anesthesia, but concentrations that rendered the fish handleable within 5 min were generally not safe for exposures longer than 15 min. Concentrations of benzocaine efficacious for fish were not acutely toxic to eggs of coho salmon (Oncorhynchus kisutch), chinook salmon (Oncorhynchus tshauiytschas, rainbow trout, brown trout, or lake trout (Salvelinus namaycush). Benzocaine is not registered for fishery use and is neither more effective nor safer than the registered anesthetic, tricaine methanesulfonate (MS-222l.

Lake trout rehabilitation in Lake Erie: a case history

Science.gov (United States)

Cornelius, Floyd C.; Muth, Kenneth M.; Kenyon, Roger

1995-01-01

Native lake trout (Salvelinus namaycush) once thrived in the deep waters of eastern Lake Erie. The impact of nearly 70 years of unregulated exploitation and over 100 years of progressively severe cultural eutrophication resulted in the elimination of lake trout stocks by 1950. Early attempts to restore lake trout by stocking were unsuccessful in establishing a self-sustaining population. In the early 1980s, New York's Department of Environmental Conservation, Pennsylvania's Fish and Boat Commission, and the U.S. Fish and Wildlife Service entered into a cooperative program to rehabilitate lake trout in the eastern basin of Lake Erie. After 11 years of stocking selected strains of lake trout in U.S. waters, followed by effective sea lamprey control, lake trout appear to be successfully recolonizing their native habitat. Adult stocks have built up significantly and are expanding their range in the lake. Preliminary investigations suggest that lake trout reproductive habitat is still adequate for natural reproduction, but natural recruitment has not been documented. Future assessments will be directed toward evaluation of spawning success and tracking age-class cohorts as they move through the fishery.

Can pelagic forage fish and spawning cisco (Coregonus artedi) biomass in the western arm of Lake Superior be assessed with a single summer survey?

Science.gov (United States)

Yule, D.L.; Stockwell, J.D.; Schreiner, D.R.; Evrard, L.M.; Balge, M.; Hrabik, T.R.

2009-01-01

Management efforts to rehabilitate lake trout Salvelinus namaycush in Lake Superior have been successful and the recent increase in their numbers has led to interest in measuring biomass of pelagic prey fish species important to these predators. Lake Superior cisco Coregonus artedi currently support roe fisheries and determining the sustainability of these fisheries is an important management issue. We conducted acoustic and midwater trawl surveys of the western arm of Lake Superior during three periods: summer (July-August), October, and November 2006 to determine if a single survey can be timed to estimate biomass of both prey fish and spawning cisco. We evaluated our methods by comparing observed trawl catches of small (cisco increased substantially in November, while small bloater Coregonus hoyi biomass was lower. We compared our summer 2006 estimates of total fish biomass to the results of a summer survey in 1997 and obtained similar results. We conclude that the temporal window for obtaining biomass estimates of pelagic prey species in the western arm of Lake Superior is wide (July through October), but estimating spawning cisco abundance is best done with a November survey.

Bioenergetic evaluation of diel vertical migration by bull trout (Salvelinus confluentus) in a thermally stratified reservoir

Science.gov (United States)

Eckmann, Madeleine; Dunham, Jason B.; Connor, Edward J.; Welch, Carmen A.

2018-01-01

Many species living in deeper lentic ecosystems exhibit daily movements that cycle through the water column, generally referred to as diel vertical migration (DVM). In this study, we applied bioenergetics modelling to evaluate growth as a hypothesis to explain DVM by bull trout (Salvelinus confluentus) in a thermally stratified reservoir (Ross Lake, WA, USA) during the peak of thermal stratification in July and August. Bioenergetics model parameters were derived from observed vertical distributions of temperature, prey and bull trout. Field sampling confirmed that bull trout prey almost exclusively on recently introduced redside shiner (Richardsonius balteatus). Model predictions revealed that deeper (>25 m) DVMs commonly exhibited by bull trout during peak thermal stratification cannot be explained by maximising growth. Survival, another common explanation for DVM, may have influenced bull trout depth use, but observations suggest there may be additional drivers of DVM. We propose these deeper summertime excursions may be partly explained by an alternative hypothesis: the importance of colder water for gametogenesis. In Ross Lake, reliance of bull trout on warm water prey (redside shiner) for consumption and growth poses a potential trade-off with the need for colder water for gametogenesis.

Understanding environmental DNA detection probabilities: A case study using a stream-dwelling char Salvelinus fontinalis

Science.gov (United States)

Wilcox, Taylor M; Mckelvey, Kevin S.; Young, Michael K.; Sepulveda, Adam; Shepard, Bradley B.; Jane, Stephen F; Whiteley, Andrew R.; Lowe, Winsor H.; Schwartz, Michael K.

2016-01-01

Environmental DNA sampling (eDNA) has emerged as a powerful tool for detecting aquatic animals. Previous research suggests that eDNA methods are substantially more sensitive than traditional sampling. However, the factors influencing eDNA detection and the resulting sampling costs are still not well understood. Here we use multiple experiments to derive independent estimates of eDNA production rates and downstream persistence from brook trout (Salvelinus fontinalis) in streams. We use these estimates to parameterize models comparing the false negative detection rates of eDNA sampling and traditional backpack electrofishing. We find that using the protocols in this study eDNA had reasonable detection probabilities at extremely low animal densities (e.g., probability of detection 0.18 at densities of one fish per stream kilometer) and very high detection probabilities at population-level densities (e.g., probability of detection > 0.99 at densities of ≥ 3 fish per 100 m). This is substantially more sensitive than traditional electrofishing for determining the presence of brook trout and may translate into important cost savings when animals are rare. Our findings are consistent with a growing body of literature showing that eDNA sampling is a powerful tool for the detection of aquatic species, particularly those that are rare and difficult to sample using traditional methods.

Use of a seismic air gun to reduce survival of nonnative lake trout embryos: A tool for conservation?

Science.gov (United States)

Cox, B.S.; Dux, A.M.; Quist, M.C.; Guy, C.S.

2012-01-01

The detrimental impacts of nonnative lake trout Salvelinus namaycush in the western USA have prompted natural resource management agencies in several states to implement lake trout suppression programs. Currently, these programs rely on mechanical removal methods (i.e., gill nets, trap nets, and angling) to capture subadult and adult lake trout. We conducted a study to explore the potential for using high-intensity sound from a relatively small (655.5 cm3 [40 in3]) seismic air gun to reduce survival of lake trout embryos. Lake trout embryos at multiple stages of development were exposed to a single discharge of the seismic air gun at two depths (5 and 15 m) and at two distances from the air gun (0.1 and 2.7 m). Control groups for each developmental stage, distance, and depth were treated identically except that the air gun was not discharged. Mortality in lake trout embryos treated at 0.1 m from the air gun was 100% at 74 daily temperature units in degrees Celsius (TU°C) at both depths. Median mortality in lake trout embryos treated at 0.1 m from the air gun at 207 TU°C (93%) and 267 °C (78%) appeared to be higher than that of controls (49% and 48%, respectively) at 15-m depth. Among the four lake trout developmental stages, exposure to the air gun at 0.1 m resulted in acute mortality up to 60% greater than that of controls. Mortality at a distance of 2.7 m did not appear to differ from that of controls at any developmental stage or at either depth. Our results indicate that seismic air guns have potential as an alternative tool for controlling nonnative lake trout, but further investigation is warranted.

Breaking the speed limit--comparative sprinting performance of brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta)

Science.gov (United States)

Castro-Santos, Theodore; Sanz-Ronda, Francisco Javier; Ruiz-Legazpi, Jorge

2013-01-01

Sprinting behavior of free-ranging fish has long been thought to exceed that of captive fish. Here we present data from wild-caught brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta), volitionally entering and sprinting against high-velocity flows in an open-channel flume. Performance of the two species was nearly identical, with the species attaining absolute speeds > 25 body lengths·s−1. These speeds far exceed previously published observations for any salmonid species and contribute to the mounting evidence that commonly accepted estimates of swimming performance are low. Brook trout demonstrated two distinct modes in the relationship between swim speed and fatigue time, similar to the shift from prolonged to sprint mode described by other authors, but in this case occurring at speeds > 19 body lengths·s−1. This is the first demonstration of multiple modes of sprint swimming at such high swim speeds. Neither species optimized for distance maximization, however, indicating that physiological limits alone are poor predictors of swimming performance. By combining distributions of volitional swim speeds with endurance, we were able to account for >80% of the variation in distance traversed by both species.

Bull trout (Salvelinus confluentus) telemetry and associated habitat data collected in a geodatabase from the upper Boise River, southwestern Idaho

Science.gov (United States)

MacCoy, Dorene E.; Shephard, Zachary M.; Benjamin, Joseph R.; Vidergar, Dmitri T.; Prisciandaro, Anthony F.

2017-03-23

Bull trout (Salvelinus confluentus), listed as threatened under the Endangered Species Act, are among the more thermally sensitive of coldwater species in North America. The Boise River upstream of Arrowrock Dam in southwestern Idaho (including Arrowrock Reservoir) provides habitat for one of the southernmost populations of bull trout. The presence of the species in Arrowrock Reservoir poses implications for dam and reservoir operations. From 2011 to 2014, the Bureau of Reclamation and the U.S. Geological Survey collected fish telemetry data to improve understanding of bull trout distribution and movement in Arrowrock Reservoir and in the upper Boise River tributaries. The U.S. Geological Survey compiled the telemetry (fish location) data, along with reservoir elevation, river discharge, precipitation, and water-quality data in a geodatabase. The geodatabase includes metadata compliant with Federal Geographic Data Committee content standards. The Bureau of Reclamation plans to incorporate the data in a decision‑support tool for reservoir management.

Fish and crustaceans in northeast Greenland lakes with special emphasis on interactions between Arctic charr (Salvelinus alpinus), Lepidurus arcticus and benthic chydorids

DEFF Research Database (Denmark)

Jeppesen, E.; Christoffersen, K.; Landkildehus, F.

2001-01-01

We studied the trophic structure in the pelagial and crustacean remains in the surface 1 cm of the sediment of 13 shallow, high arctic lakes in northeast Greenland (74 N). Seven lakes were fishless, while the remaining six hosted a dwarf form of Arctic charr (Salvelinus alpinus). In fishless lakes...... sp. in lakes with Lepidurus, while they were abundant in lakes with fish. The low abundance in fishless lakes could not be explained by damage of crustacean remains caused by Lepidurus feeding in the sediment, because remains of the more soft-shelled, pelagic-living Daphnia were abundant...... in the sediment of these lakes. No significant differences between lakes with and without fish were found in chlorophyll a, total phosphorus, total nitrogen, conductivity or temperature, suggesting that the observed link between Lepidurus arcticus and the benthic crustacean community is causal. Consequently...

Differences in organotin accumulation in relation to life history in the white-spotted charr Salvelinus leucomaenis

International Nuclear Information System (INIS)

Ohji, Madoka; Harino, Hiroya; Arai, Takaomi

2011-01-01

Research highlights: → Otolith Sr:Ca ratios in sea-run type were higher than those in freshwater-residents. → TBT and TPT concentrations in sea-run type were higher than those in freshwater-residents. → Sea-run type have higher risk of TBT and TPT than freshwater-residents in white-spotted charr. - Abstract: To examine the accumulation pattern of organotins (OTs) in relation to the migration of diadromous fish, tributyltin (TBT) and triphenyltin (TPT) and their derivatives were determined in the muscle tissue of both sea-run (anadromous) and freshwater-resident (nonanadromous) types of the white-spotted charr Salvelinus leucomaenis. Ontogenic changes in otolith strontium (Sr) and calcium (Ca) concentrations were examined along life history transect to discriminate migration type. Mean Sr:Ca ratio from the core to the edge of the otolith in sea-run individuals was significantly higher than those in freshwater-resident one. There were no significant correlations in S. leucomaenis between OT accumulation and various biological characteristics. It is noteworthy that TBT and TPT concentrations in sea-run type were significantly higher than those in freshwater-resident individuals, although they are both of the same species. These results suggest that sea-run S. leucomaenis have a higher ecological risk of OT exposure than freshwater-residents during their life histories.

Extensive feeding on sockeye salmon Oncorhynchus nerka smolts by bull trout Salvelinus confluentus during initial outmigration into a small, unregulated and inland British Columbia river

Science.gov (United States)

Furey, Nathan B.; Hinch, Scott G.; Lotto, A.G.; Beauchamp, David A.

2015-01-01

Stomach contents were collected and analysed from 22 bull trout Salvelinus confluentus at the edge of the Chilko Lake and Chilko River in British Columbia, Canada, during spring outmigration of sockeye salmon Oncorhynchus nerka smolts. Twenty of the 22 (>90%) stomachs contained prey items, virtually all identifiable prey items were outmigrant O. nerka smolts and stomach contents represented a large portion (0·0–12·6%) of estimated S. confluentus mass. The results demonstrate nearly exclusive and intense feeding by S. confluentus on outmigrant smolts, and support recent telemetry observations of high disappearance rates of O. nerka smolts leaving large natural lake systems prior to entering high-order unregulated river systems.

Do predators influence the distribution of age-0 kokanee in a Colorado Reservoir?

Science.gov (United States)

Hardiman, J.M.; Johnson, B.M.; Martinez, P.J.

2004-01-01

Seasonal changes in reservoir conditions such as productivity, light, and temperature create spatiotemporal variation in habitat that may segregate or aggregate predators and prey, producing implications for the distribution, growth, and survival of fishes. We used hydroacoustics to document the diel vertical distribution of age-0 kokanee Oncorhynchus nerka relative to environmental gradients at Blue Mesa Reservoir, Colorado, during May-August of 2002. Temperature, light, and zooplankton density profiles were examined relative to foraging conditions for kokanee and their primary predator, lake trout Salvelinus namaycush. Age-0 kokanee displayed large diel vertical migrations in May despite the lack of an energetic advantage before reservoir stratification. Age-0 kokanee minimized near-surface foraging at this time, perhaps to avoid predation by visual predators, such as lake trout, in the well-lit surface waters. Strong reservoir stratification in midsummer appeared to provide a thermal refuge from lake trout that the kokanee exploited. By August vertical migrations were shallow and most kokanee remained in the epilimnion throughout the day. Although the energetic implications of the late-summer strategy are unclear, it appears that kokanee were responding to changes in their predator environment. A robust model for kokanee diel vertical migration across a range of systems should include a predator avoidance component.

Challenge to the model of lake charr evolution: Shallow- and deep-water morphs exist within a small postglacial lake

Science.gov (United States)

Chavarie, Louise; Muir, Andrew M.; Zimmerman, Mara S.; Baillie, Shauna M.; Hansen, Michael J.; Nate, Nancy A.; Yule, Daniel L.; Middel, Trevor; Bentzen, Paul; Krueger, Charles C.

2016-01-01

All examples of lake charr (Salvelinus namaycush) diversity occur within the largest, deepest lakes of North America (i.e. > 2000 km2). We report here Rush Lake (1.3 km2) as the first example of a small lake with two lake charr morphs (lean and huronicus). Morphology, diet, life history, and genetics were examined to demonstrate the existence of morphs and determine the potential influence of evolutionary processes that led to their formation or maintenance. Results showed that the huronicus morph, caught in deep-water, had a deeper body, smaller head and jaws, higher eye position, greater buoyancy, and deeper peduncle than the shallow-water lean morph. Huronicus grew slower to a smaller adult size, and had an older mean age than the lean morph. Genetic comparisons showed low genetic divergence between morphs, indicating incomplete reproductive isolation. Phenotypic plasticity and differences in habitat use between deep and shallow waters associated with variation in foraging opportunities seems to have been sufficient to maintain the two morphs, demonstrating their important roles in resource polymorphism. Rush Lake expands previous explanations for lake charr intraspecific diversity, from large to small lakes and from reproductive isolation to the presence of gene flow associated with strong ecological drivers.

Angler-caught piscivore diets reflect fish community changes in Lake Huron

Science.gov (United States)

Roseman, Edward F.; Schaeffer, Jeff; Bright, Ethan; Fielder, David G.

2014-01-01

Examination of angler-caught piscivore stomachs revealed that Lake Trout Salvelinus namaycush, Chinook Salmon Oncorhynchus tshawytscha, and Walleyes Sander vitreus altered theirdiets in response to unprecedented declines in Lake Huron's main-basin prey fish community.Diets varied by predator species, season, and location but were nearly always dominated numerically by some combination of Alewife Alosa pseudoharengus, Rainbow Smelt Osmerus mordax, Emerald Shiner Notropis atherinoides, Round Goby Neogobius melanostomus, or terrestrial insects. Rainbow Trout Oncorhynchus mykiss (steelhead), Coho Salmon Oncorhynchus kisutch, and Atlantic Salmon Salmo salar had varied diets that reflected higher contributions of insects. Compared with an earlier (1983–1986) examination of angler-caught predator fishes from Lake Huron, the contemporary results showed an increase in consumption of nontraditional prey (including conspecifics), use of smaller prey, and an increase in insects in the diet, suggesting that piscivores were faced with chronic prey limitation during this study. The management of all piscivores in Lake Huron will likely require consideration of the pervasive effects of changes in food webs, especially if prey fish remain at low levels.

Genetically based population divergence in overwintering energy mobilization in brook charr (Salvelinus fontinalis).

Science.gov (United States)

Crespel, Amélie; Bernatchez, Louis; Garant, Dany; Audet, Céline

2013-03-01

Investigating the nature of physiological traits potentially related to fitness is important towards a better understanding of how species and/or populations may respond to selective pressures imposed by contrasting environments. In northern species in particular, the ability to mobilize energy reserves to compensate for the low external energy intake during winter is crucial. However, the phenotypic and genetic bases of energy reserve accumulation and mobilization have rarely been investigated, especially pertaining to variation in strategy adopted by different populations. In the present study, we documented variation in several energy reserve variables and estimated their quantitative genetic basis to test the null hypothesis of no difference in variation at those traits among three strains of brook charr (Salvelinus fontinalis) and their reciprocal hybrids. Our results indicate that the strategy of winter energy preparation and mobilization was specific to each strain, whereby (1) domestic fish accumulated a higher amount of energy reserves before winter and kept accumulating liver glycogen during winter despite lower feeding; (2) Laval fish used liver glycogen and lipids during winter and experienced a significant decrease in condition factor; (3) Rupert fish had relatively little energy reserves accumulated at the end of fall and preferentially mobilized visceral fat during winter. Significant heritability for traits related to the accumulation and use of energy reserves was found in the domestic and Laval but not in the Rupert strain. Genetic and phenotypic correlations also varied among strains, which suggested population-specific genetic architecture underlying the expression of these traits. Hybrids showed limited evidence of non-additive effects. Overall, this study provides the first evidence of a genetically based-and likely adaptive-population-specific strategy for energy mobilization related to overwinter survival.

Biochemical characterization of the Arctic char (Salvelinus alpinus ovarian progestin membrane receptor

Directory of Open Access Journals (Sweden)

Thomas Peter

2005-11-01

Full Text Available Abstract Membrane progestin receptors are involved in oocyte maturation in teleosts. However, the maturation-inducing steroid (MIS does not appear to be conserved among species and several progestins may fulfill this function. So far, complete biochemical characterization has only been performed on a few species. In the present study we have characterized the membrane progestin receptor in Arctic char (Salvelinus alpinus and show that the 17,20beta-dihydroxy-4-pregnen-3-one (17,20beta-P receptor also binds several xenobiotics, thus rendering oocyte maturation sensitive to environmental pollutants. We identified a single class of high affinity (Kd, 13.8 ± 1.1 nM, low capacity (Bmax, 1.6 ± 0.6 pmol/g ovary binding sites by saturation and Scatchard analyses. Receptor binding displayed rapid association and dissociation kinetics typical of steroid membrane receptors, with t1/2 s of less than 1 minute. The 17,20beta-P binding also displayed tissue specificity with high, saturable, and specific 17,20beta-P binding detected in ovaries, heart and gills while no specific binding was observed in muscle, brain or liver. Changes in 17,20beta-P binding during oocyte maturation were consistent with its identity as the oocyte MIS membrane receptor. Incubation of fully-grown ovarian follicles with gonadotropin induced oocyte maturation, which was accompanied by a five-fold increase in 17,20beta-P receptor binding. In addition, competition studies with a variety of steroids revealed that receptor binding is highly specific for 17,20beta-P, the likely maturation-inducing steroid (MIS in Arctic char. The relative-binding affinities of all the other progestogens and steroids tested were less than 5% of that of 17,20beta-P for the receptor. Several ortho, para derivatives of DDT also showed weak binding affinity for the 17,20beta-P receptor supporting the hypothesis that xenobiotics may bind steroid receptors on the oocyte's surface and might thereby interfere

Spatial and temporal movement dynamics of brook Salvelinus fontinalis and brown trout Salmo trutta

Science.gov (United States)

Davis, L.A.; Wagner, Tyler; Barton, Meredith L.

2015-01-01

Native eastern brook trout Salvelinus fontinalis and naturalized brown trout Salmo trutta occur sympatrically in many streams across the brook trout’s native range in the eastern United States. Understanding within- among-species variability in movement, including correlates of movement, has implications for management and conservation. We radio tracked 55 brook trout and 45 brown trout in five streams in a north-central Pennsylvania, USA watershed to quantify the movement of brook trout and brown trout during the fall and early winter to (1) evaluate the late-summer, early winter movement patterns of brook trout and brown trout, (2) determine correlates of movement and if movement patterns varied between brook trout and brown trout, and (3) evaluate genetic diversity of brook trout within and among study streams, and relate findings to telemetry-based observations of movement. Average total movement was greater for brown trout (mean ± SD = 2,924 ± 4,187 m) than for brook trout (mean ± SD = 1,769 ± 2,194 m). Although there was a large amount of among-fish variability in the movement of both species, the majority of movement coincided with the onset of the spawning season, and a threshold effect was detected between stream flow and movement: where movement increased abruptly for both species during positive flow events. Microsatellite analysis of brook trout revealed consistent findings to those found using radio-tracking, indicating a moderate to high degree of gene flow among brook trout populations. Seasonal movement patterns and the potential for relatively large movements of brook and brown trout highlight the importance of considering stream connectivity when restoring and protecting fish populations and their habitats.

Evaluation of glutamic acid and glycine as sources of nonessential amino acids for lake trout (Salvelinus namaycush) and rainbow trout (Salmo gairdnerii)

Science.gov (United States)

Hughes, S.G.

1985-01-01

1. A semi-purified test diet which contained either glutamic acid or glycine as the major source of nonessential amino acids (NEAA) was fed to lake and rainbow trout.2. Trout fed the diet containing glutamic acid consistently showed better growth and feed conversion efficiencies than those fed the diets containing glycine.3. The data indicate that these trout utilize glutamic acid more efficiently than glycine when no other major sources of NEAA are present.

Sex Chromosome Evolution, Heterochiasmy, and Physiological QTL in the Salmonid Brook Charr Salvelinus fontinalis

Directory of Open Access Journals (Sweden)

Ben J.G. Sutherland

2017-08-01

Full Text Available Whole-genome duplication (WGD can have large impacts on genome evolution, and much remains unknown about these impacts. This includes the mechanisms of coping with a duplicated sex determination system and whether this has an impact on increasing the diversity of sex determination mechanisms. Other impacts include sexual conflict, where alleles having different optimums in each sex can result in sequestration of genes into nonrecombining sex chromosomes. Sex chromosome development itself may involve sex-specific recombination rate (i.e., heterochiasmy, which is also poorly understood. The family Salmonidae is a model system for these phenomena, having undergone autotetraploidization and subsequent rediploidization in most of the genome at the base of the lineage. The salmonid master sex determining gene is known, and many species have nonhomologous sex chromosomes, putatively due to transposition of this gene. In this study, we identify the sex chromosome of Brook Charr Salvelinus fontinalis and compare sex chromosome identities across the lineage (eight species and four genera. Although nonhomology is frequent, homologous sex chromosomes and other consistencies are present in distantly related species, indicating probable convergence on specific sex and neo-sex chromosomes. We also characterize strong heterochiasmy with 2.7-fold more crossovers in maternal than paternal haplotypes with paternal crossovers biased to chromosome ends. When considering only rediploidized chromosomes, the overall heterochiasmy trend remains, although with only 1.9-fold more recombination in the female than the male. Y chromosome crossovers are restricted to a single end of the chromosome, and this chromosome contains a large interspecific inversion, although its status between males and females remains unknown. Finally, we identify quantitative trait loci (QTL for 21 unique growth, reproductive, and stress-related phenotypes to improve knowledge of the genetic

Radiocaesium turnover in Arctic charr (Salvelinus alpinus) and brown trout (Salmo trutta) in a Norwegian lake

International Nuclear Information System (INIS)

Forseth, T.; Ugedal, O.; Jonsson, B.; Langeland, A.; Njaastad, O.

1991-01-01

The radioactivity of brown trout (Salmo trutta L.) and Arctic charr (Salvelinus alpinus (L.)) was monitored in a Norwegian lake from 1986 to 1989. A distinct difference was observed between brown trout and Arctic charr in the accumulation of radiocaesium ( 134 Cs and 137 Cs) from the Chernobyl fallout, and the study focused on the understanding of this difference. Brown trout had a large food consumption and a corresponding high intake of radiocaesium. Excretion was 20% faster in brown trout than Arctic charr as brown trout lived at high temperatures in epilimnic water. Arctic charr had a lower food consumption (less than one-third of trout) and lived in colder meta-and hypolimnic water. Arctic charr therefore had a lower intake and slower excretion of radiocaesium. Brown trout an Arctic charr had different diets. For brown trout zoobenthos was the dominant food item, whereas Artic charr mainly fed on zooplankton. The radioactivity in the stomach contents of the two species was different in 1986, but similar for the rest of the period. Higher levels of radiocaesium in brown trout than Arctic charr in 1986 were due to a higher food consumption and more radioactive food items in its diet. The parallel development in accumulated radiocaesium through summer 1987 was probably formed by brown trout balancing a higher intake with a faster excretion. The ecological half-lives of radiocaesium in brown trout (357 days) and Arctic charr (550 days) from Lake Hoeysjoeen indicated a slow removal of the isotopes from the food webs. (author)

Visual sensitivity of deepwater fishes in Lake Superior.

Directory of Open Access Journals (Sweden)

Kelly A Harrington

Full Text Available The predator-prey interactions in the offshore food web of Lake Superior have been well documented, but the sensory systems mediating these interactions remain unknown. The deepwater sculpin, (Myoxocephalus thompsoni, siscowet (Salvelinus namaycush siscowet, and kiyi (Coregonus kiyi inhabit low light level environments. To investigate the potential role of vision in predator-prey interactions, electroretinography was used to determine visual sensitivity for each species. Spectral sensitivity curves revealed peak sensitivity at 525 nm for each species which closely corresponds to the prevalent downwelling light spectrum at depth. To determine if sufficient light was available to mediate predator-prey interactions, visual sensitivity was correlated with the intensity of downwelling light in Lake Superior to construct visual depth profiles for each species. Sufficient daytime irradiance exists for visual interactions to approximately 325 m for siscowet and kiyi and 355 m for the deepwater sculpin during summer months. Under full moon conditions, sufficient irradiance exists to elicit ERG response to light available at approximately 30 m for the siscowet and kiyi and 45 m for the deepwater sculpin. Visual interactions are therefore possible at the depths and times when these organisms overlap in the water column indicating that vision may play a far greater role at depth in deep freshwater lakes than had been previously documented.

Factors Affecting Mercury Stable Isotopic Distribution in Piscivorous Fish of the Laurentian Great Lakes.

Science.gov (United States)

Lepak, Ryan F; Janssen, Sarah E; Yin, Runsheng; Krabbenhoft, David P; Ogorek, Jacob M; DeWild, John F; Tate, Michael T; Holsen, Thomas M; Hurley, James P

2018-03-06

Identifying the sources of methylmercury (MeHg) and tracing the transformations of mercury (Hg) in the aquatic food web are important components of effective strategies for managing current and legacy Hg sources. In our previous work, we measured stable isotopes of Hg (δ 202 Hg, Δ 199 Hg, and Δ 200 Hg) in the Laurentian Great Lakes and estimated source contributions of Hg to bottom sediment. Here, we identify isotopically distinct Hg signatures for Great Lakes trout ( Salvelinus namaycush) and walleye ( Sander vitreus), driven by both food-web and water-quality characteristics. Fish contain high values for odd-isotope mass independent fractionation (MIF) with averages ranging from 2.50 (western Lake Erie) to 6.18‰ (Lake Superior) in Δ 199 Hg. The large range in odd-MIF reflects variability in the depth of the euphotic zone, where Hg is most likely incorporated into the food web. Even-isotope MIF (Δ 200 Hg), a potential tracer for Hg from precipitation, appears both disconnected from lake sedimentary sources and comparable in fish among the five lakes. We suggest that similar to the open ocean, water-column methylation also occurs in the Great Lakes, possibly transforming recently deposited atmospheric Hg deposition. We conclude that the degree of photochemical processing of Hg is controlled by phytoplankton uptake rather than by dissolved organic carbon quantity among lakes.

Behavioural and physiological responses of brook trout Salvelinus fontinalis to midwinter flow reduction in a small ice-free mountain stream.

Science.gov (United States)

Krimmer, A N; Paul, A J; Hontela, A; Rasmussen, J B

2011-09-01

This study presents an experimental analysis of the effects of midwinter flow reduction (50-75%, reduction in discharge in 4 h daily pulses) on the physical habitat and on behaviour and physiology of overwintering brook trout Salvelinus fontinalis in a small mountain stream. Flow reduction did not result in significant lowering of temperature or formation of surface or subsurface ice. The main findings were (1) daily movement by S. fontinalis increased (c. 2·5-fold) during flow reduction, but was limited to small-scale relocations (reduced during flow reduction. (3) Although both experimental and reference fish did lose mass and condition during the experiment, no effects of flow reduction on stress indicators (blood cortisol or glucose) or bioenergetics (total body fat, water content or mass loss) were detected, probably because access to the preferred type of cover remained available. Like other salmonids, S. fontinalis moves little and seeks physical cover during winter. Unlike many of the more studied salmonids, however, this species overwinters successfully in small groundwater-rich streams that often remain ice-free, and this study identifies undercut banks as the critical winter habitat rather than substratum cover. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

Feeding habits of the alien brook trout Salvelinus fontinalis and the native brown trout Salmo trutta in Czech mountain streams

Directory of Open Access Journals (Sweden)

Horká Petra

2017-01-01

Full Text Available Quantifying patterns of prey resource use is fundamental to identify mechanisms enabling the coexistence of related fish species. Trophic interactions between the native brown trout, Salmo trutta, and the introduced brook trout, Salvelinus fontinalis, were studied monthly from May to October in three mountain streams in Central Europe (Czech Republic. To evaluate whether the feeding habits differ between separated and coexisting populations of these species, one locality where both species coexist, and two allopatric populations of either species were studied. Across the study period, the mean stomach fullness of fish varied, being highest in spring and declining through autumn. The diet overlap (Schoener's overlap index between the species increased through the studied season (from 54.5% in July to 81.5% in October. In allopatry, both species had nearly the same feeding habits. However, in sympatry, brook trout consumed higher proportion of terrestrial invertebrates, while brown trout showed no changes either in the proportions of aquatic and terrestrial prey utilized or in the selectivity for prey categories in comparison to allopatric conditions. The dietary shift observed for brook trout, but not for brown trout, suggests that brown trout is a stronger competitor in the studied sympatric locality, leading the brook trout to change its feeding habits to reduce interspecific competition.

Distribution of Po-210 and Pb-210 in Arctic Char (Salvelinus alpinus) from an Arctic freshwater lake

Energy Technology Data Exchange (ETDEWEB)

Gwynn, J.P.; Rudolfsen, G. [Norwegian Radiation Protection Authority, The Fram Centre, Tromsoe (Norway)

2014-07-01

There is little information available with regard to the accumulation of Po-210 and Pb-210 by freshwater fish in natural freshwater systems despite the potential for relevant ingestion doses to man. This is maybe of particular pertinence for certain population groups where freshwater fish are an important dietary food item. Equally, it is important to understand the body distributions of these naturally occurring radionuclides to quantify the resulting doses to different tissues and organs of freshwater fish. With regard to the latter, it is important to consider not only the doses arising from bio-accumulated Po-210 and Pb-210 in various body compartments but additionally the internal dose from unabsorbed Po-210 and Pb-210 in the digestive tract. In this study, activity concentrations of Po-210 and Pb-210 were determined in muscle and various internal organs of Arctic Charr (Salvelinus alpinus) sampled from a lake in the Norwegian Arctic (69 deg. 4' N, 19 deg. 20' E). Observed activity concentrations of Po-210 and Pb-210 in different tissues will be discussed in relation to physiological parameters and ambient lake water activity concentrations. Results from this study will be compared to two similar studies conducted in freshwater systems where elevated activity concentrations of these radionuclides have been observed. Ingestion dose rates to man and effective absorbed dose rates to different tissues and organs of Arctic Charr from Po-210 and Pb-210 will be derived and compared to those from observed activity concentrations of the anthropogenic radionuclide Cs-137. (authors)

Perturbation in protein expression of the sterile salmonid hybrids between female brook trout Salvelinus fontinalis and male masu salmon Oncorhynchus masou during early spermatogenesis.

Science.gov (United States)

Zheng, Liang; Senda, Yoshie; Abe, Syuiti

2013-05-01

Most males and females of intergeneric hybrid (BM) between female brook trout (Bt) Salvelinus fontinalis and male masu salmon (Ms) Oncorhynchus masou had undeveloped gonads, with abnormal germ cell development shown by histological examination. To understand the cause of this hybrid sterility, expression profiles of testicular proteins in the BM and parental species were examined with 2-DE coupled with MALDI-TOF/TOF MS. Compared with the parental species, more than 60% of differentially expressed protein spots were down-regulated in BM. A total of 16 up-regulated and 48 down-regulated proteins were identified in BM. Up-regulated were transferrin and other somatic cell-predominant proteins, whereas down-regulated were some germ cell-specific proteins such as DEAD box RNA helicase Vasa. Other pronouncedly down-regulated proteins included tubulins and heat shock proteins that are supposed to have roles in spermatogenesis. The present findings suggest direct association of the observed perturbation in protein expression with the failure of spermatogenesis and the sterility in the examined salmonid hybrids. Copyright © 2013 Elsevier B.V. All rights reserved.

Role of cortisol in stocking density-induced changes in growth and metabolism of brook charr (Salvelinus fontinalis)

Energy Technology Data Exchange (ETDEWEB)

Vijayan, M.M.

1990-01-01

Brook charr (Salvelinus fontinalis) held at high stocking density (SD) (120 kg/m{sup 3}) had a lower growth rate, food consumption and food conversion efficiency, and plasma thyroxine (T4) than those held at low SD (30 kg/m{sup 3}). SD had no effect on plasma triiodothyronine (T3) levels. Plasma cortisol levels in fish maintained at high SD were variable, being either lower with increased SD or not different from the low SD group. Head kidney tissue (containing the interrenal cells) preparations of brook charr held at high SD showed a higher spontaneous cortisol secretion rate. There was no difference in the clearance rate of ({sup 3}H)-cortisol from plasma, but liver from fish held at high SD showed higher cortisol uptake and catabolism, indicative of altered hepatic metabolic activity. High SD appears to alter the energy metabolism of brook charr. This was evident from significant changes between densities in levels of metabolites (plasma glucose and liver glycogen) and activities of key hepatic enzymes (PFK, HK, FBPase, G6PDH, HOAD, GK and G3PDH). These results suggests that high SD has the effect of mobilizing triglycerides, and promoting gluconeogenesis from glycerol, but has little effect on protein metabolism. When cortisol was administered to brook charr in the form of slow release intraperitoneal implants, the metabolic changes evident were similar to those observed in fish held at high SD. There was no consistent increase in plasma cortisol levels of cortisol implanted fish over a 90 day period. Nevertheless, there were significant effects, apparently cortisol-related, on certain metabolite levels (plasma glycerol, plasma glucose, hepatic glycogen), and activities of key hepatic enzymes.

The diet of introduced brook trout (Salvelinus fontinalis; Mitchill, 1814 in an alpine area and a literature review on its feeding ecology

Directory of Open Access Journals (Sweden)

Rocco Tiberti

2016-05-01

Full Text Available Introduced fish are a major threat for high altitude aquatic habitats and Salvelinus fontinalis have been widely used throughout the Alps for stocking lakes and rivers. Understanding its feeding ecology is a basic, but essential tool for interpreting its impact. To assess which factors determine the diet of S. fontinalis we analyzed more than 500 stomachs from several introduced populations from the Gran Paradiso National Park (GPNP, Western Italian Alps and we measured the availability of several prey groups (zooplankton, aquatic invertebrates, terrestrial invertebrates. We complemented the study with a short, but exhaustive literature review on the S. fontinalis feeding ecology. In general the food composition reflected the availability of prey -confirming that S. fontinalis is an opportunistic predator- and was influenced by habitat type (stream vs lake, fish size, and seasonality. The obtained results were discussed in the light of the existing literature on the feeding ecology and ecological impact of S. fontinalis. Large benthonic insects account for a substantial part of  the diet of stream dwelling brook trout, while they are almost absent both in the diet and in the prey species pool of lake-dwelling brook trout, probably reflecting a stronger ecological impact in the lakes.

Effectiveness of egg immersion in aqueous solutions of thiamine and thiamine analogs for reducing early mortality syndrome

Science.gov (United States)

Brown, S.B.; Brown, L.R.; Brown, M.; Moore, K.; Villella, M.; Fitzsimons, J.D.; Williston, B.; Honeyfield, D.C.; Hinterkopf, J.P.; Tillitt, D.E.; Zajicek, J.L.; Wolgamood, M.

2005-01-01

Protocols used for therapeutic thiamine treatments in salmonine early mortality syndrome (EMS) were investigated in lake trout Salvelinus namaycush and coho salmon Oncorhynchus kisutch to assess their efficacy. At least 500 mg of thiamine HCl/L added to egg baths was required to produce a sustained elevation of thiamine content in lake trout eggs. Thiamine uptake from egg baths was not influenced by a pH ranging from 5.5 to 7.5 or by a water hardness between 2 and 200 mg CaCO3/L. There was poorer thiamine uptake when initial thiamine levels were low, suggesting that current treatment regimes may not be as effective when thiamine levels are severely depressed and that higher treatment doses are necessary. Exposure of eggs to the more lipid-soluble thiamine analog allithiamine (1,000 mg/L) during water hardening increased egg thiamine levels by 1.5-2.5 nmol/g and was completely effective at reversing EMS. Another more lipid-soluble thiamine analog, benfotiamine (100 mg/L), reduced EMS but did not produce detectable increases in egg thiamine content. Although benfotiamine may be more effective than thiamine at mitigating EMS, it is more expensive than thiamine HCl or allithiamine. In addition, there still needs to be a more thorough examination of dose-response relationships. We conclude that allithiamine is an alternative to the use of thiamine in egg baths as a therapeutic treatment for salmonid EMS. ?? Copyright by the American Fisheries Society 2005.

Seasonal patterns in growth, blood consumption, and effects on hosts by parasitic-phase sea lampreys in the Great Lakes: an individual-based model approach

Science.gov (United States)

Madenjian, Charles P.; Cochran, Philip A.; Bergstedt, Roger A.

2003-01-01

An individual-based model (IBM) was developed for sea lamprey (Petromyzon marinus) populations in the Laurentian Great Lakes. The IBM was then calibrated to observed growth, by season, for sea lampreys in northern Lake Huron under two different water temperature regimes: a regime experienced by Seneca-strain lake trout (Salvelinus namaycush) and a regime experienced by Marquettestrain lake trout. Modeling results indicated that seasonal blood consumption under the Seneca regime was very similar to that under the Marquette regime. Simulated mortality of lake trout directly due to blood removal by sea lampreys occurred at nearly twice the rate during August and September under the Marquette regime than under the Seneca regime. However, cumulative sea lamprey-induced mortality on lake trout over the entire duration of the sea lamprey's parasitic phase was only 7% higher for the Marquette regime compared with the Seneca regime. Thus, these modeling results indicated that the strain composition of the host (lake trout) population was not important in determining total number of lake trout deaths or total blood consumption attributable to the sea lamprey population, given the sea lamprey growth pattern. Regardless of water temperature regime, both blood consumption rate by sea lampreys and rate of sea lamprey-induced mortality on lake trout peaked in late October. Elevated blood consumption in late October appeared to be unrelated to changes in water temperature. The IBM approach should prove useful in optimizing control of sea lampreys in the Laurentian Great Lakes.

Effects of exotic species on Yellowstone's grizzly bears

Science.gov (United States)

Reinhart, Daniel P.; Haroldson, Mark A.; Mattson, D.J.; Gunther, Kerry A.

2001-01-01

Humans have affected grizzly bears (Ursus arctos horribilis) by direct mortality, competition for space and resources, and introduction of exotic species. Exotic organisms that have affected grizzly bears in the Greater Yellowstone Area include common dandelion (Taraxacum officinale), nonnative clovers (Trifolium spp.), domesticated livestock, bovine brucellosis (Brucella abortus), lake trout (Salvelinus namaycush), and white pine blister rust (Cronartium ribicola). Some bears consume substantial amounts of dandelion and clover. However, these exotic foods provide little digested energy compared to higher-quality bear foods. Domestic livestock are of greater energetic value, but use of this food by bears often leads to conflicts with humans and subsequent increases in bear mortality. Lake trout, blister rust, and brucellosis diminish grizzly bears foods. Lake trout prey on native cutthroat trout (Oncorhynchus clarkii) in Yellowstone Lake; white pine blister rust has the potential to destroy native whitebark pine (Pinus albicaulis) stands; and management response to bovine brucellosis, a disease found in the Yellowstone bison (Bison bison) and elk (Cervus elaphus), could reduce populations of these 2 species. Exotic species will likely cause more harm than good for Yellowstone grizzly bears. Managers have few options to mitigate or contain the impacts of exotics on Yellowstone's grizzly bears. Moreover, their potential negative impacts have only begun to unfold. Exotic species may lead to the loss of substantial highquality grizzly bear foods, including much of the bison, trout, and pine seeds that Yellowstone grizzly bears currently depend upon.

Impact of thiamine deficiency on T-cell dependent and T-cell independent antibody production in lake trout

Science.gov (United States)

Ottinger, Christopher A.; Honeyfield, Dale C.; Densmore, Christine L.; Iwanowicz, Luke R.

2012-01-01

Lake trout Salvelinus namaycush on thiamine-replete and thiamine-depleted diets were evaluated for the effects of thiamine status on in vivo responses to the T-dependent antigen trinitophenol (TNP)-keyhole limpet hemocyanin (TNP-KLH), the T-independent antigen trinitrophenol-lipolysaccaharide (TNP-LPS), or Dulbecco's phosphate-buffered saline (DPBS; negative control fish). Plasma antibody concentrations were evaluated for possible differences in total anti-TNP activity as well as differences in response kinetics. Associations between anti-TNP activity and muscle and liver thiamine concentrations as well as ratios of muscle-to-liver thiamine to anti-TNP activity were also examined. Thiamine-depleted lake trout that were injected with TNP-LPS exhibited significantly more anti-TNP activity than thiamine-replete fish. The depleted fish injected with TNP-LPS also exhibited significantly different response kinetics relative to thiamine-replete lake trout. No differences in activity or kinetics were observed between the thiamine-replete and -depleted fish injected with TNP-KLH or in the DPBS negative controls. Anti-TNP activity in thiamine-depleted lake trout injected with TNP-KLH was positively associated with muscle thiamine pyrophosphate (thiamine diphosphate; TPP) concentration. A negative association was observed between the ratio of muscle-to-liver TPP and T-independent responses. No significant associations between anti-TNP activity and tissue thiamine concentration were observed in the thiamine-replete fish. We demonstrated that thiamine deficiency leads to alterations in both T-dependent and T-independent immune responses in lake trout.

Impact of thiamine deficiency on T-cell dependent and T-cell independent antibody production in lake trout.

Science.gov (United States)

Ottinger, Christopher A; Honeyfield, Dale C; Densmore, Christine L; Iwanowicz, Luke R

2012-12-01

Lake trout Salvelinus namaycush on thiamine-replete and thiamine-depleted diets were evaluated for the effects of thiamine status on in vivo responses to the T-dependent antigen trinitophenol (TNP)-keyhole limpet hemocyanin (TNP-KLH), the T-independent antigen trinitrophenol-lipolysaccaharide (TNP-LPS), or Dulbecco's phosphate-buffered saline (DPBS; negative control fish). Plasma antibody concentrations were evaluated for possible differences in total anti-TNP activity as well as differences in response kinetics. Associations between anti-TNP activity and muscle and liver thiamine concentrations as well as ratios of muscle-to-liver thiamine to anti-TNP activity were also examined. Thiamine-depleted lake trout that were injected with TNP-LPS exhibited significantly more anti-TNP activity than thiamine-replete fish. The depleted fish injected with TNP-LPS also exhibited significantly different response kinetics relative to thiamine-replete lake trout. No differences in activity or kinetics were observed between the thiamine-replete and -depleted fish injected with TNP-KLH or in the DPBS negative controls. Anti-TNP activity in thiamine-depleted lake trout injected with TNP-KLH was positively associated with muscle thiamine pyrophosphate (thiamine diphosphate; TPP) concentration. A negative association was observed between the ratio of muscle-to-liver TPP and T-independent responses. No significant associations between anti-TNP activity and tissue thiamine concentration were observed in the thiamine-replete fish. We demonstrated that thiamine deficiency leads to alterations in both T-dependent and T-independent immune responses in lake trout.

Effect of rearing density on poststocking survival of lake trout in Lake Ontario

Science.gov (United States)

Elrod, Joseph H.; Ostergaard, David E.; Schneider, Clifford P.

1989-01-01

Six paired lots of yearling lake trout (Salvelinus namaycush) reared at densities of 41,000 and 51,000 fish per raceway during their last 9 months in the hatchery were stocked in Lake Ontario. Poststocking survival of the high-density (HD) and low-density (LD) fish was not different for the 1982 year-class. However, for the 1983 year-class, mean survival was significantly different between HD and LD fish (P Mean survival of HD fish was only 76% that of LD fish (P Mean size at stocking was not different for HD and LD fish of the 1982 year-class, but for the 1983 year-class, the LD fish were 6% longer and 22% heavier than the HD fish. Mean lengths and weights of LD and HD fish were not different in samples collected in Lake Ontario at age 2 and older. Size at stocking was not likely the factor that caused the difference in survival. Rather, the rearing conditions (probably water exchange rate in relation to number of fish in the raceway) that resulted in slower growth of the HD fish of the 1983 year-class also caused them to be poorer physiologically than the LD fish. The number of yearling lake trout per rearing unit that will result in maximum contribution to populations in the Great Lakes after stocking may be lower than the rearing densities customarily used at some hatcheries.

pH preference and avoidance responses of adult brook trout Salvelinus fontinalis and brown trout Salmo trutta.

Science.gov (United States)

Fost, B A; Ferreri, C P

2015-03-01

The pH preferred and avoided by wild, adult brook trout Salvelinus fontinalis and brown trout Salmo trutta was examined in a series a laboratory tests using gradual and steep-gradient flow-through aquaria. The results were compared with those published for the observed segregation patterns of juvenile S. fontinalis and S. trutta in Pennsylvania streams. The adult S. trutta tested showed a preference for pH 4·0 while adult S. fontinalis did not prefer any pH within the range tested. Salmo trutta are not found in Pennsylvania streams with a base-flow pH < 5·8 which suggests that S. trutta prefer pH well above 4·0. Adult S. trutta displayed a lack of avoidance at pH below 5·0, as also reported earlier for juveniles. The avoidance pH of wild, adult S. fontinalis (between pH 5·5 and 6·0) and S. trutta (between pH 6·5 and 7·0) did not differ appreciably from earlier study results for the avoidance pH of juvenile S. fontinalis and S. trutta. A comparison of c.i. around these avoidance estimates indicates that avoidance pH is similar among adult S. fontinalis and S. trutta in this study. The limited overlap of c.i. for avoidance pH values for the two species, however, suggests that some S. trutta will display avoidance at a higher pH when S. fontinalis will not. The results of this study indicate that segregation patterns of adult S. fontinalis and S. trutta in Pennsylvania streams could be related to pH and that competition with S. trutta could be mediating the occurrence of S. fontinalis at some pH levels. © 2015 The Fisheries Society of the British Isles.

Fine-scale population structure and riverscape genetics of brook trout (Salvelinus fontinalis) distributed continuously along headwater channel networks

Science.gov (United States)

Kanno, Yoichiro; Vokoun, Jason C.; Letcher, Benjamin H.

2011-01-01

Linear and heterogeneous habitat makes headwater stream networks an ideal ecosystem in which to test the influence of environmental factors on spatial genetic patterns of obligatory aquatic species. We investigated fine-scale population structure and influence of stream habitat on individual-level genetic differentiation in brook trout (Salvelinus fontinalis) by genotyping eight microsatellite loci in 740 individuals in two headwater channel networks (7.7 and 4.4 km) in Connecticut, USA. A weak but statistically significant isolation-by-distance pattern was common in both sites. In the field, many tagged individuals were recaptured in the same 50-m reaches within a single field season (summer to fall). One study site was characterized with a hierarchical population structure, where seasonal barriers (natural falls of 1.5–2.5 m in height during summer base-flow condition) greatly reduced gene flow and perceptible spatial patterns emerged because of the presence of tributaries, each with a group of genetically distinguishable individuals. Genetic differentiation increased when pairs of individuals were separated by high stream gradient (steep channel slope) or warm stream temperature in this site, although the evidence of their influence was equivocal. In a second site, evidence for genetic clusters was weak at best, but genetic differentiation between individuals was positively correlated with number of tributary confluences. We concluded that the population-level movement of brook trout was limited in the study headwater stream networks, resulting in the fine-scale population structure (genetic clusters and clines) even at distances of a few kilometres, and gene flow was mitigated by ‘riverscape’ variables, particularly by physical barriers, waterway distance (i.e. isolation-by-distance) and the presence of tributaries.

Analysis of trade-offs between threats of invasion by nonnative brook trout (Salvelinus fontinalis) and intentional isolation for native westslope cutthroat trout (Oncorhynchus clarkii lewisi)

Science.gov (United States)

Peterson, D.P.; Rieman, B.E.; Dunham, J.B.; Fausch, K.D.; Young, M.K.

2008-01-01

Native salmonid fishes often face simultaneous threats from habitat fragmentation and invasion by nonnative trout species. Unfortunately, management actions to address one may create or exacerbate the other. A consistent decision process would include a systematic analysis of when and where intentional use or removal of barriers is the most appropriate action. We developed a Bayesian belief network as a tool for such analyses. We focused on native westslope cutthroat trout (Oncorhynchus clarkii lewisi) and nonnative brook trout (Salvelinus fontinalis) and considered the environmental factors influencing both species, their potential interactions, and the effects of isolation on the persistence of local cutthroat trout populations. The trade-offs between isolation and invasion were strongly influenced by size and habitat quality of the stream network to be isolated and existing demographic linkages within and among populations. An application of the model in several sites in western Montana (USA) showed the process could help clarify management objectives and options and prioritize conservation actions among streams. The approach can also facilitate communication among parties concerned with native salmonids, nonnative fish invasions, barriers and intentional isolation, and management of the associated habitats and populations. ?? 2008 NRC.

Sibship reconstruction for inferring mating systems, dispersal and effective population size in headwater brook trout (Salvelinus fontinalis) populations

Science.gov (United States)

Kanno, Yoichiro; Vokoun, Jason C.; Letcher, Benjamin H.

2011-01-01

Brook trout Salvelinus fontinalis populations have declined in much of the native range in eastern North America and populations are typically relegated to small headwater streams in Connecticut, USA. We used sibship reconstruction to infer mating systems, dispersal and effective population size of resident (non-anadromous) brook trout in two headwater stream channel networks in Connecticut. Brook trout were captured via backpack electrofishing using spatially continuous sampling in the two headwaters (channel network lengths of 4.4 and 7.7 km). Eight microsatellite loci were genotyped in a total of 740 individuals (80–140 mm) subsampled in a stratified random design from all 50 m-reaches in which trout were captured. Sibship reconstruction indicated that males and females were both mostly polygamous although single pair matings were also inferred. Breeder sex ratio was inferred to be nearly 1:1. Few large-sized fullsib families (>3 individuals) were inferred and the majority of individuals were inferred to have no fullsibs among those fish genotyped (family size = 1). The median stream channel distance between pairs of individuals belonging to the same large-sized fullsib families (>3 individuals) was 100 m (range: 0–1,850 m) and 250 m (range: 0–2,350 m) in the two study sites, indicating limited dispersal at least for the size class of individuals analyzed. Using a sibship assignment method, the effective population size for the two streams was estimated at 91 (95%CI: 67–123) and 210 (95%CI: 172–259), corresponding to the ratio of effective-to-census population size of 0.06 and 0.12, respectively. Both-sex polygamy, low variation in reproductive success, and a balanced sex ratio may help maintain genetic diversity of brook trout populations with small breeder sizes persisting in headwater channel networks.

Eryptosis in lead-exposed workers

International Nuclear Information System (INIS)

Aguilar-Dorado, Itzel-Citlalli; Hernández, Gerardo; Quintanar-Escorza, Martha-Angelica; Maldonado-Vega, María; Rosas-Flores, Margarita; Calderón-Salinas, José-Víctor

2014-01-01

Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8 μg/dl) and non-exposed workers (4.2 μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca 2+ ] i and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (< 0.1%), but lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca 2+ ], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications. - Graphical abstract: Fig. 1. (A) Blood lead concentration (PbB) and (B) phosphatidylserine externalization on erythrocyte membranes of non-lead exposed (□) and lead exposed workers (■). Values are mean ± SD. *Significantly different (P < 0.001). - Highlights: • Erythrocytes of lead exposed workers showed higher PS

Eryptosis in lead-exposed workers

Energy Technology Data Exchange (ETDEWEB)

Aguilar-Dorado, Itzel-Citlalli [Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico); Hernández, Gerardo [Section of Methodology of Science, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico); Quintanar-Escorza, Martha-Angelica [Faculty of Medicine, UJED, Durango, DGO (Mexico); Maldonado-Vega, María [CIATEC, León, GTO (Mexico); Rosas-Flores, Margarita [Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico); Calderón-Salinas, José-Víctor, E-mail: jcalder@cinvestav.mx [Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico)

2014-12-01

Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8 μg/dl) and non-exposed workers (4.2 μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca{sup 2+}]{sub i} and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (< 0.1%), but lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca{sup 2+}], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications. - Graphical abstract: Fig. 1. (A) Blood lead concentration (PbB) and (B) phosphatidylserine externalization on erythrocyte membranes of non-lead exposed (□) and lead exposed workers (■). Values are mean ± SD. *Significantly different (P < 0.001). - Highlights: • Erythrocytes of lead exposed workers

Mercury levels in herring gulls and fish: 42 years of spatio-temporal trends in the Great Lakes.

Science.gov (United States)

Blukacz-Richards, E Agnes; Visha, Ariola; Graham, Matthew L; McGoldrick, Daryl L; de Solla, Shane R; Moore, David J; Arhonditsis, George B

2017-04-01

Total mercury levels in aquatic birds and fish communities have been monitored across the Canadian Great Lakes by Environment and Climate Change Canada (ECCC) for the past 42 years (1974-2015). These data (22 sites) were used to examine spatio-temporal variability of mercury levels in herring gull (Larus argentatus) eggs, lake trout (Salvelinus namaycush), walleye (Sander vitreus), and rainbow smelt (Osmerus mordax). Trends were quantified with dynamic linear models, which provided time-variant rates of change of mercury concentrations. Lipid content (in both fish and eggs) and length in fish were used as covariates in all models. For the first three decades, mercury levels in gull eggs and fish declined at all stations. In the 2000s, trends for herring gull eggs reversed at two sites in Lake Erie and two sites in Lake Ontario. Similar trend reversals in the 2000s were observed for lake trout in Lake Superior and at a single station in Lake Ontario. Mercury levels in lake trout continued to slowly decline at all of the remaining stations, except for Lake Huron, where the levels remained stable. A post-hoc Bayesian regression analysis suggests strong trophic interactions between herring gulls and rainbow smelt in Lake Superior and Lake Ontario, but also pinpoints the likelihood of a trophic decoupling in Lake Huron and Lake Erie. Continued monitoring of mercury levels in herring gulls and fish is required to consolidate these trophic shifts and further evaluate their broader implications. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Evaluating stocking efficacy in an ecosystem undergoing oligotrophication

Science.gov (United States)

Kao, Yu-Chun; Rogers, Mark W.; Bunnell, David B.

2017-01-01

Oligotrophication has negatively affected fisheries production in many freshwater ecosystems and could conceivably reduce the efficacy of stockings used to enhance fisheries. In Lake Michigan, offshore oligotrophication has occurred since the 1970s, owing to reductions in total phosphorus (TP) inputs and nearshore sequestration of TP by nonindigenous dreissenid mussels. We evaluated simultaneous effects of stock enhancement and oligotrophication on salmonine species (Chinook salmon Oncorhynchus tshawytscha, lake trout Salvelinus namaycush, and steelhead O. mykiss) that support valuable recreational fisheries. We employed a novel application of an Ecopath with Ecosim model by conducting a full factorial simulation experiment. Our design included multiple levels of salmonine stocking, consumption by invasive quagga mussels (Dreissena bugensis), and TP that were informed by manager interests. Under all levels of TP and quagga mussel consumption, our results showed that stock enhancement could still increase salmonine biomass, but positive responses were stronger for lake trout and steelhead than Chinook salmon. Simulations showed that quagga mussel consumption has deleterious effects on pelagic-oriented prey fishes and Chinook salmon, which feed almost exclusively on the pelagic-oriented alewife (Alosa pseudoharengus). In summary, results from our simulation experiment suggested that lake trout and steelhead are better suited to the current ecosystem than Chinook salmon, and therefore, stock enhancement provides the highest gains for these two species. Furthermore, simulated biomass of all recreational salmonine species increased with increasing TP, indicating the need for managers to consider how potential future oligotrophication will limit the carrying capacity of salmonine biomass in Lake Michigan

Coupling age-structured stock assessment and fish bioenergetics models: a system of time-varying models for quantifying piscivory patterns during the rapid trophic shift in the main basin of Lake Huron

Science.gov (United States)

He, Ji X.; Bence, James R.; Madenjian, Charles P.; Pothoven, Steven A.; Dobiesz, Norine E.; Fielder, David G.; Johnson, James E.; Ebener, Mark P.; Cottrill, Adam R.; Mohr, Lloyd C.; Koproski, Scott R.

2015-01-01

We quantified piscivory patterns in the main basin of Lake Huron during 1984–2010 and found that the biomass transfer from prey fish to piscivores remained consistently high despite the rapid major trophic shift in the food webs. We coupled age-structured stock assessment models and fish bioenergetics models for lake trout (Salvelinus namaycush), Chinook salmon (Oncorhynchus tshawytscha), walleye (Sander vitreus), and lake whitefish (Coregonus clupeaformis). The model system also included time-varying parameters or variables of growth, length–mass relations, maturity schedules, energy density, and diets. These time-varying models reflected the dynamic connections that a fish cohort responded to year-to-year ecosystem changes at different ages and body sizes. We found that the ratio of annual predation by lake trout, Chinook salmon, and walleye combined with the biomass indices of age-1 and older alewives (Alosa pseudoharengus) and rainbow smelt (Osmerus mordax) increased more than tenfold during 1987–2010, and such increases in predation pressure were structured by relatively stable biomass of the three piscivores and stepwise declines in the biomass of alewives and rainbow smelt. The piscivore stability was supported by the use of alternative energy pathways and changes in relative composition of the three piscivores. In addition, lake whitefish became a new piscivore by feeding on round goby (Neogobius melanostomus). Their total fish consumption rivaled that of the other piscivores combined, although fish were still a modest proportion of their diet. Overall, the use of alternative energy pathways by piscivores allowed the increases in predation pressure on dominant diet species.

Lake trout in northern Lake Huron spawn on submerged drumlins

Science.gov (United States)

Riley, Stephen C.; Binder, Thomas; Wattrus, Nigel J.; Faust, Matthew D.; Janssen, John; Menzies, John; Marsden, J. Ellen; Ebener, Mark P.; Bronte, Charles R.; He, Ji X.; Tucker, Taaja R.; Hansen, Michael J.; Thompson, Henry T.; Muir, Andrew M.; Krueger, Charles C.

2014-01-01

Recent observations of spawning lake trout Salvelinus namaycush near Drummond Island in northern Lake Huron indicate that lake trout use drumlins, landforms created in subglacial environments by the action of ice sheets, as a primary spawning habitat. From these observations, we generated a hypothesis that may in part explain locations chosen by lake trout for spawning. Most salmonines spawn in streams where they rely on streamflows to sort and clean sediments to create good spawning habitat. Flows sufficient to sort larger sediment sizes are generally lacking in lakes, but some glacial bedforms contain large pockets of sorted sediments that can provide the interstitial spaces necessary for lake trout egg incubation, particularly if these bedforms are situated such that lake currents can penetrate these sediments. We hypothesize that sediment inclusions from glacial scavenging and sediment sorting that occurred during the creation of bedforms such as drumlins, end moraines, and eskers create suitable conditions for lake trout egg incubation, particularly where these bedforms interact with lake currents to remove fine sediments. Further, these bedforms may provide high-quality lake trout spawning habitat at many locations in the Great Lakes and may be especially important along the southern edge of the range of the species. A better understanding of the role of glacially-derived bedforms in the creation of lake trout spawning habitat may help develop powerful predictors of lake trout spawning locations, provide insight into the evolution of unique spawning behaviors by lake trout, and aid in lake trout restoration in the Great Lakes.

Quantification of 15 bile acids in lake charr feces by ultra-high performance liquid chromatography–tandem mass spectrometry

Science.gov (United States)

Li, Ke; Buchinger, Tyler J.; Bussy, Ugo; Fissette, Skye D.; Johnson, Nicholas; Li, Weiming

2015-01-01

Many fishes are hypothesized to use bile acids (BAs) as chemical cues, yet quantification of BAs in biological samples and the required methods remain limited. Here, we present an UHPLC–MS/MS method for simultaneous, sensitive, and rapid quantification of 15 BAs, including free, taurine, and glycine conjugated BAs, and application of the method to fecal samples from lake charr (Salvelinus namaycush). The analytes were separated on a C18 column with acetonitrile–water (containing 7.5 mM ammonium acetate and 0.1% formic acid) as mobile phase at a flow rate of 0.25 mL/min for 12 min. BAs were monitored with a negative electrospray triple quadrupole mass spectrometer (Xevo TQ-S™). Calibration curves of 15 BAs were linear over the concentration range of 1.00–5,000 ng/mL. Validation revealed that the method was specific, accurate, and precise. The method was applied to quantitative analysis of feces extract of fry lake charr and the food they were eating. The concentrations of analytes CA, TCDCA, TCA, and CDCA were 242.3, 81.2, 60.7, and 36.2 ng/mg, respectively. However, other taurine conjugated BAs, TUDCA, TDCA, and THDCA, were not detected in feces of lake charr. Interestingly, TCA and TCDCA were detected at high concentrations in food pellets, at 71.9 and 38.2 ng/mg, respectively. Application of the method to feces samples from lake charr supported a role of BAs as chemical cues, and will enhance further investigation of BAs as chemical cues in other fish species.

Factors influencing the distribution of native bull trout and westslope cutthroat trout in western Glacier National Park, Montana

Science.gov (United States)

D'Angelo, Vincent S.; Muhlfeld, Clint C.

2013-01-01

The widespread declines of native bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarkii lewisi) populations prompted researchers to investigate factors influencing their distribution and status in western Glacier National Park, Montana. We evaluated the association of a suite of abiotic factors (stream width, elevation, gradient, large woody debris density, pool density, August mean stream temperature, reach surface area) with the occurrence (presence or absence) of bull trout and westslope cutthroat trout in 79 stream reaches in five sub-drainages containing glacial lakes. We modeled the occurrence of each species using logistic regression and evaluated competing models using an information theoretic approach. Westslope cutthroat trout were widely distributed (47 of 79 reaches), and there appeared to be no restrictions on their distribution other than physical barriers. Westslope cutthroat trout were most commonly found in relatively warm reaches downstream of lakes and in headwater reaches with large amounts of large woody debris and abundant pools. By contrast, bull trout were infrequently detected (10 of 79 reaches), with 7 of the 10 (70%) detections in sub-drainages that have not been compromised by non-native lake trout (S. namaycush). Bull trout were most often found in cold, low-gradient reaches upstream of glacial lakes. Our results indicate that complex stream habitats in sub-drainages free of non-native species are important to the persistence of native salmonids in western Glacier National Park. Results from this study may help managers monitor and protect important habitats and populations, inform conservation and recovery programs, and guide non-native species suppression efforts in Glacier National Park and elsewhere.

Egg fatty acid composition from lake trout fed two Lake Michigan prey fish species.

Science.gov (United States)

Honeyfield, D.C.; Fitzsimons, J.D.; Tillitt, D.E.; Brown, S.B.

2009-01-01

We previously demonstrated that there were significant differences in the egg thiamine content in lake trout Salvelinus namaycush fed two Lake Michigan prey fish (alewife Alosa pseudoharengus and bloater Coregonus hoyi). Lake trout fed alewives produced eggs low in thiamine, but it was unknown whether the consumption of alewives affected other nutritionally important components. In this study we investigated the fatty acid composition of lake trout eggs when females were fed diets that resulted in different egg thiamine concentrations. For 2 years, adult lake trout were fed diets consisting of four combinations of captured alewives and bloaters (100% alewives; 65% alewives, 35% bloaters; 35% alewives, 65% bloaters; and 100% bloaters). The alewife fatty acid profile had higher concentrations of arachidonic acid and total omega-6 fatty acids than the bloater profile. The concentrations of four fatty acids (cis-13, 16-docosadienoic, eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids) were higher in bloaters than in alewives. Although six fatty acid components were higher in lake trout eggs in 2001 than in 2000 and eight fatty acids were lower, diet had no effect on any fatty acid concentration measured in lake trout eggs in this study. Based on these results, it appears that egg fatty acid concentrations differ between years but that the egg fatty acid profile does not reflect the alewife-bloater mix in the diet of adults. The essential fatty acid content of lake trout eggs from females fed alewives and bloaters appears to be physiologically regulated and adequate to meet the requirements of developing embryos.

Fish populations in a large group of acid-stressed lakes

Energy Technology Data Exchange (ETDEWEB)

Harvey, H H

1975-01-01

The purpose of this study was to determine the effects of environmental stress on the number and diversity of fish species in a group of acid-stressed lakes. The study area was the La Cloche Mountains, a series of quartzite ridges covering 1,300 km/sup 2/ along the north shore of Georgian Bay and north channel of Lake Huron. Within these ridges are 173 lakes; 68 of the largest of these made up the study sample. The lakes of the La Cloche Mountains are undergoing rapid acidification. Coincident with this there has been the loss of sport fishes from several lakes. Lakes such as Nellie, Lumsden, O.S.A., Acid and Killarney supported good sport fisheries for the lake trout, (Salvelinus namaycush) for many years, but have ceased to do so in the last 5 to 15 years. Other sport fishes, notably the walleye (Stizostedion vitreum) and smallmouth bass (micropterus dolomieu) have disappeared from some of the La Cloche Lakes. Thus recreational fishing alone could not have been the cause of the change. Beamish (1974) recorded the extreme sparcity of the three remaining fish species in O.S.A. Lake. Many of the lakes of the La Cloche mountains are accessible only with difficulty and little or no information exists for these lakes prior to this study. This precluded simple comparison of these lakes before and during acidification. This lack of historic data determined in part the approach taken in this study; a comparison of the fish communities of a group of lakes differing in degree of acid stress.

Effects of lake trout refuges on lake whitefish and cisco in the Apostle Islands Region of Lake Superior

Science.gov (United States)

Zuccarino-Crowe , Chiara M.; Taylor, William W.; Hansen, Michael J.; Seider, Michael J.; Krueger, Charles C.

2016-01-01

Lake trout refuges in the Apostle Islands region of Lake Superior are analogous to the concept of marine protected areas. These refuges, established specifically for lake trout (Salvelinus namaycush) and closed to most forms of recreational and commercial fishing, were implicated as one of several management actions leading to successful rehabilitation of Lake Superior lake trout. To investigate the potential significance of Gull Island Shoal and Devils Island Shoal refuges for populations of not only lake trout but also other fish species, relative abundances of lake trout, lake whitefish (Coregonus clupeaformis), and cisco (Coregonus artedi) were compared between areas sampled inside versus outside of refuge boundaries. During 1982–2010, lake trout relative abundance was higher and increased faster inside the refuges, where lake trout fishing was prohibited, than outside the refuges. Over the same period, lake whitefish relative abundance increased faster inside than outside the refuges. Both evaluations provided clear evidence that refuges protected these species. In contrast, trends in relative abundance of cisco, a prey item of lake trout, did not differ significantly between areas inside and outside the refuges. This result did not suggest indirect or cascading refuge effects due to changes in predator levels. Overall, this study highlights the potential of species-specific refuges to benefit other fish species beyond those that were the refuges' original target. Improved understanding of refuge effects on multiple species of Great Lakes fishes can be valuable for developing rationales for refuge establishment and predicting associated fish community-level effects.

Eryptosis in lead-exposed workers.

Science.gov (United States)

Aguilar-Dorado, Itzel-Citlalli; Hernández, Gerardo; Quintanar-Escorza, Martha-Angelica; Maldonado-Vega, María; Rosas-Flores, Margarita; Calderón-Salinas, José-Víctor

2014-12-01

Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8μg/dl) and non-exposed workers (4.2μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca(2+)]i and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca(2+)], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications. Copyright © 2014 Elsevier Inc. All rights reserved.

The developmental transcriptome of contrasting Arctic charr (Salvelinus alpinus morphs [version 2; referees: 1 approved, 2 approved with reservations

Directory of Open Access Journals (Sweden)

Johannes Gudbrandsson

2016-04-01

Full Text Available Species and populations with parallel evolution of specific traits can help illuminate how predictable adaptations and divergence are at the molecular and developmental level. Following the last glacial period, dwarfism and specialized bottom feeding morphology evolved rapidly in several landlocked Arctic charr Salvelinus alpinus populations in Iceland.   To study the genetic divergence between small benthic morphs and limnetic morphs, we conducted RNA-sequencing charr embryos at four stages in early development. We studied two stocks with contrasting morphologies: the small benthic (SB charr from Lake Thingvallavatn and Holar aquaculture (AC charr. The data reveal significant differences in expression of several biological pathways during charr development. There was also an expression difference between SB- and AC-charr in genes involved in energy metabolism and blood coagulation genes. We confirmed differing expression of five genes in whole embryos with qPCR, including lysozyme and natterin-like which was previously identified as a fish-toxin of a lectin family that may be a putative immunopeptide. We also verified differential expression of 7 genes in the developing head that associated consistently with benthic v.s.limnetic morphology (studied in 4 morphs. Comparison of single nucleotide polymorphism (SNP frequencies reveals extensive genetic differentiation between the SB and AC-charr (~1300 with more than 50% frequency difference. Curiously, three derived alleles in the otherwise conserved 12s and 16s mitochondrial ribosomal RNA genes are found in benthic charr. The data implicate multiple genes and molecular pathways in divergence of small benthic charr and/or the response of aquaculture charr to domestication. Functional, genetic and population genetic studies on more freshwater and anadromous populations are needed to confirm the specific loci and mutations relating to specific ecological traits in Arctic charr.

The developmental transcriptome of contrasting Arctic charr (Salvelinus alpinus morphs [version 3; referees: 1 approved, 2 approved with reservations

Directory of Open Access Journals (Sweden)

Johannes Gudbrandsson

2016-12-01

Full Text Available Species and populations with parallel evolution of specific traits can help illuminate how predictable adaptations and divergence are at the molecular and developmental level. Following the last glacial period, dwarfism and specialized bottom feeding morphology evolved rapidly in several landlocked Arctic charr Salvelinus alpinus populations in Iceland.   To study the genetic divergence between small benthic morphs and limnetic morphs, we conducted RNA-sequencing charr embryos at four stages in early development. We studied two stocks with contrasting morphologies: the small benthic (SB charr from Lake Thingvallavatn and Holar aquaculture (AC charr. The data reveal significant differences in expression of several biological pathways during charr development. There was also an expression difference between SB- and AC-charr in genes involved in energy metabolism and blood coagulation genes. We confirmed differing expression of five genes in whole embryos with qPCR, including lysozyme and natterin-like which was previously identified as a fish-toxin of a lectin family that may be a putative immunopeptide. We also verified differential expression of 7 genes in the developing head that associated consistently with benthic v.s.limnetic morphology (studied in 4 morphs. Comparison of single nucleotide polymorphism (SNP frequencies reveals extensive genetic differentiation between the SB and AC-charr (~1300 with more than 50% frequency difference. Curiously, three derived alleles in the otherwise conserved 12s and 16s mitochondrial ribosomal RNA genes are found in benthic charr. The data implicate multiple genes and molecular pathways in divergence of small benthic charr and/or the response of aquaculture charr to domestication. Functional, genetic and population genetic studies on more freshwater and anadromous populations are needed to confirm the specific loci and mutations relating to specific ecological traits in Arctic charr.

Nucleotide variation in the mitochondrial genome provides evidence for dual routes of postglacial recolonization and genetic recombination in the northeastern brook trout (Salvelinus fontinalis).

Science.gov (United States)

Pilgrim, B L; Perry, R C; Barron, J L; Marshall, H D

2012-09-26

Levels and patterns of mitochondrial DNA (mtDNA) variation were examined to investigate the population structure and possible routes of postglacial recolonization of the world's northernmost native populations of brook trout (Salvelinus fontinalis), which are found in Labrador, Canada. We analyzed the sequence diversity of a 1960-bp portion of the mitochondrial genome (NADH dehydrogenase 1 gene and part of cytochrome oxidase 1) of 126 fish from 32 lakes distributed throughout seven regions of northeastern Canada. These populations were found to have low levels of mtDNA diversity, a characteristic trait of populations at northern extremes, with significant structuring at the level of the watershed. Upon comparison of northeastern brook trout sequences to the publicly available brook trout whole mitochondrial genome (GenBank AF154850), we infer that the GenBank sequence is from a fish whose mtDNA has recombined with that of Arctic charr (S. alpinus). The haplotype distribution provides evidence of two different postglacial founding groups contributing to present-day brook trout populations in the northernmost part of their range; the evolution of the majority of the haplotypes coincides with the timing of glacier retreat from Labrador. Our results exemplify the strong influence that historical processes such as glaciations have had on shaping the current genetic structure of northern species such as the brook trout.

Buildings exposed to fire

International Nuclear Information System (INIS)

1987-01-01

The 24 lectures presented to the colloquium cover the following subject fields: (1) Behaviour of structural components exposed to fire; (2) Behaviour of building materials exposed to fire; (3) Thermal processes; (4) Safety related, theoretical studies. (PW) [de

A SNP Based Linkage Map of the Arctic Charr (Salvelinus alpinus Genome Provides Insights into the Diploidization Process After Whole Genome Duplication

Directory of Open Access Journals (Sweden)

Cameron M. Nugent

2017-02-01

Full Text Available Diploidization, which follows whole genome duplication events, does not occur evenly across the genome. In salmonid fishes, certain pairs of homeologous chromosomes preserve tetraploid loci in higher frequencies toward the telomeres due to residual tetrasomic inheritance. Research suggests this occurs only in homeologous pairs where one chromosome arm has undergone a fusion event. We present a linkage map for Arctic charr (Salvelinus alpinus, a salmonid species with relatively fewer chromosome fusions. Genotype by sequencing identified 19,418 SNPs, and a linkage map consisting of 4508 markers was constructed from a subset of high quality SNPs and microsatellite markers that were used to anchor the new map to previous versions. Both male- and female-specific linkage maps contained the expected number of 39 linkage groups. The chromosome type associated with each linkage group was determined, and 10 stable metacentric chromosomes were identified, along with a chromosome polymorphism involving the sex chromosome AC04. Two instances of a weak form of pseudolinkage were detected in the telomeric regions of homeologous chromosome arms in both female and male linkage maps. Chromosome arm homologies within the Atlantic salmon (Salmo salar and rainbow trout (Oncorhynchus mykiss genomes were determined. Paralogous sequence variants (PSVs were identified, and their comparative BLASTn hit locations showed that duplicate markers exist in higher numbers on seven pairs of homeologous arms, previously identified as preserving tetrasomy in salmonid species. Homeologous arm pairs where neither arm has been part of a fusion event in Arctic charr had fewer PSVs, suggesting faster diploidization rates in these regions.

Brook trout (Salvelinus fontinalis extinction in small boreal lakes revealed by ephippia pigmentation: a preliminary analysis

Directory of Open Access Journals (Sweden)

Alexandre Bérubé Tellier

2016-12-01

Full Text Available Ephippium pigmentation is a plastic trait which can be related to a trade-off between visual predation pressure and better protection of cladoceran eggs against different types of stress. Experimental studies showed that planktivorous fish exert a greater predation pressure on individuals carrying darker ephippia, but little is known about the variation of ephippium pigmentation along gradients of fish predation pressure in natural conditions. For this study, our experimental design included four small boreal lakes with known fish assemblages. Two of the lakes have viable brook trout (Salvelinus fontinalis populations, whereas the other two lakes experienced brook trout extinctions during the 20th century. Cladoceran ephippia were extracted from sediment cores at layers corresponding to the documented post- extinction phase (1990's and from an older layer (1950's for which the brook trout population status is not known precisely. Our first objective was to determine whether brook trout extinction has a direct effect on both ephippium pigmentation and size. Our second objective was to give a preliminary assessment of the status of brook trout populations in the 1950's by comparing the variation in ephippia traits measured from this layer to those measured in the 1990's, for which the extinction patterns are well known. Cost-effective image analysis was used to assess variation in pigmentation levels in ephippia. This approach provided a proxy for the amount of melanin invested in each ephippium analysed. Our study clearly shows that ephippium pigmentation may represent a better indicator of the presence of fish predators than ephippium size, a trait that showed a less clear pattern of variation between lakes with and without fish. For the 1990's period, ephippia from fishless lakes were darker and showed a slight tendency to be larger than ephippia from lakes with brook trout. However, no clear differences in either ephippium size or pigmentation

EXPOSE-R2: The Astrobiological ESA Mission on Board of the International Space Station

Directory of Open Access Journals (Sweden)

Elke Rabbow

2017-08-01

Full Text Available On July 23, 2014, the Progress cargo spacecraft 56P was launched from Baikonur to the International Space Station (ISS, carrying EXPOSE-R2, the third ESA (European Space Agency EXPOSE facility, the second EXPOSE on the outside platform of the Russian Zvezda module, with four international astrobiological experiments into space. More than 600 biological samples of archaea, bacteria (as biofilms and in planktonic form, lichens, fungi, plant seeds, triops eggs, mosses and 150 samples of organic compounds were exposed to the harsh space environment and to parameters similar to those on the Mars surface. Radiation dosimeters distributed over the whole facility complemented the scientific payload. Three extravehicular activities later the chemical samples were returned to Earth on March 2, 2016, with Soyuz 44S, having spent 588 days in space. The biological samples arrived back later, on June 18, 2016, with 45S, after a total duration in space of 531 days. The exposure of the samples to Low Earth Orbit vacuum lasted for 531 days and was divided in two parts: protected against solar irradiation during the first 62 days, followed by exposure to solar radiation during the subsequent 469 days. In parallel to the space mission, a Mission Ground Reference (MGR experiment with a flight identical Hardware and a complete flight identical set of samples was performed at the premises of DLR (German Aerospace Center in Cologne by MUSC (Microgravity User Support Center, according to the mission data either downloaded from the ISS (temperature data, facility status, inner pressure status or provided by RedShift Design and Engineering BVBA, Belgium (calculated ultra violet radiation fluence data. In this paper, the EXPOSE-R2 facility, the experimental samples, mission parameters, environmental parameters, and the overall mission and MGR sequences are described, building the background for the research papers of the individual experiments, their analysis and results.

Structured decision making for conservation of bull trout (Salvelinus confluentus) in Long Creek, Klamath River Basin, south-central Oregon

Science.gov (United States)

Benjamin, Joseph R.; McDonnell, Kevin; Dunham, Jason B.; Brignon, William R.; Peterson, James T.

2017-06-21

With the decline of bull trout (Salvelinus confluentus), managers face multiple, and sometimes contradictory, management alternatives for species recovery. Moreover, effective decision-making involves all stakeholders influenced by the decisions (such as Tribal, State, Federal, private, and non-governmental organizations) because they represent diverse objectives, jurisdictions, policy mandates, and opinions of the best management strategy. The process of structured decision making is explicitly designed to address these elements of the decision making process. Here we report on an application of structured decision making to a population of bull trout believed threatened by high densities of nonnative brook trout (S. fontinalis) and habitat fragmentation in Long Creek, a tributary to the Sycan River in the Klamath River Basin, south-central Oregon. This involved engaging stakeholders to identify (1) their fundamental objectives for the conservation of bull trout, (2) feasible management alternatives to achieve their objectives, and (3) biological information and assumptions to incorporate in a decision model. Model simulations suggested an overarching theme among the top decision alternatives, which was a need to simultaneously control brook trout and ensure that the migratory tactic of bull trout can be expressed. More specifically, the optimal management decision, based on the estimated adult abundance at year 10, was to combine the eradication of brook trout from Long Creek with improvement of downstream conditions (for example, connectivity or habitat conditions). Other top decisions included these actions independently, as well as electrofishing removal of brook trout. In contrast, translocating bull trout to a different stream or installing a barrier to prevent upstream spread of brook trout had minimal or negative effects on the bull trout population. Moreover, sensitivity analyses suggested that these actions were consistently identified as optimal across

Climate change expands the spatial extent and duration of preferred thermal habitat for lake Superior fishes.

Directory of Open Access Journals (Sweden)

Timothy J Cline

Full Text Available Climate change is expected to alter species distributions and habitat suitability across the globe. Understanding these shifting distributions is critical for adaptive resource management. The role of temperature in fish habitat and energetics is well established and can be used to evaluate climate change effects on habitat distributions and food web interactions. Lake Superior water temperatures are rising rapidly in response to climate change and this is likely influencing species distributions and interactions. We use a three-dimensional hydrodynamic model that captures temperature changes in Lake Superior over the last 3 decades to investigate shifts in habitat size and duration of preferred temperatures for four different fishes. We evaluated habitat changes in two native lake trout (Salvelinus namaycush ecotypes, siscowet and lean lake trout, Chinook salmon (Oncorhynchus tshawytscha, and walleye (Sander vitreus. Between 1979 and 2006, days with available preferred thermal habitat increased at a mean rate of 6, 7, and 5 days per decade for lean lake trout, Chinook salmon, and walleye, respectively. Siscowet lake trout lost 3 days per decade. Consequently, preferred habitat spatial extents increased at a rate of 579, 495 and 419 km(2 per year for the lean lake trout, Chinook salmon, and walleye while siscowet lost 161 km(2 per year during the modeled period. Habitat increases could lead to increased growth and production for three of the four fishes. Consequently, greater habitat overlap may intensify interguild competition and food web interactions. Loss of cold-water habitat for siscowet, having the coldest thermal preference, could forecast potential changes from continued warming. Additionally, continued warming may render more suitable conditions for some invasive species.

Seasonally dynamic diel vertical migrations of Mysis diluviana, coregonine fishes, and siscowet lake trout in the pelagia of western Lake Superior

Science.gov (United States)

Ahrenstorff, Tyler D.; Hrabik, Thomas R.; Stockwell, Jason D.; Yule, Daniel L.; Sass, Greg G.

2011-01-01

Diel vertical migrations are common among many aquatic species and are often associated with changing light levels. The underlying mechanisms are generally attributed to optimizing foraging efficiency or growth rates and avoiding predation risk (μ). The objectives of this study were to (1) assess seasonal and interannual changes in vertical migration patterns of three trophic levels in the Lake Superior pelagic food web and (2) examine the mechanisms underlying the observed variability by using models of foraging, growth, and μ. Our results suggest that the opossum shrimp Mysis diluviana, kiyi Coregonus kiyi, and siscowet lake trout Salvelinus namaycush migrate concurrently during each season, but spring migrations are less extensive than summer and fall migrations. In comparison with M. diluviana, kiyis, and siscowets, the migrations by ciscoes C. artedi were not as deep in the water column during the day, regardless of season. Foraging potential and μ probably drive the movement patterns of M. diluviana, while our modeling results indicate that movements by kiyis and ciscoes are related to foraging opportunity and growth potential and receive a lesser influence from μ. The siscowet is an abundant apex predator in the pelagia of Lake Superior and probably undertakes vertical migrations in the water column to optimize foraging efficiency and growth. The concurrent vertical movement patterns of most species are likely to facilitate nutrient transport in this exceedingly oligotrophic ecosystem, and they demonstrate strong linkages between predators and prey. Fishery management strategies should use an ecosystem approach and should consider how altering the densities of long-lived top predators produces cascading effects on the nutrient cycling and energy flow in lower trophic levels.

Nutritional Status among the Children of Age Group 5-14 Years in Selected Arsenic Exposed and Non-Exposed Areas of Bangladesh.

Science.gov (United States)

Rezaul Karim, Mohammad; Ahmad, Sk Akhtar

2014-12-01

To assess and compare the nutritional status of children aged 5-14 years in arsenic exposed and non- exposed areas. It was a cross sectional study conducted on 600 children of age 5-14 years from arsenic exposed and non-exposed areas in Bangladesh. Designed questionnaire and check list were used for collection of data. To estimate BMI necessary anthropometric measurements of the studied children were done. Dietary intakes of the study children were assessed using 24-hours recall method. The difference of socio-economic conditions between the children of exposed area and non-exposed area was not significant. On an average the body mass index was found to be significantly (p < 0.01) lower among the children of arsenic exposed area (49%) in comparison to that of children in non-exposed area (38%). Stunting (p < 0.01), wasting (p < 0.05) and underweight (p < 0.05) were significantly higher in exposed group in comparison to non-exposed group. No significant difference of nutrition intake was found between exposed and non-exposed children as well as thin and normal children. In this study children exposed to arsenic contaminated water were found to be suffered from lower nutritional status.

Investigations of bull trout (Salvelinus confluentus), steelhead trout (Oncorhynchus mykiss), and spring chinook salmon (O. tshawytscha) interactions in Southeast Washington streams. Final report 1992

International Nuclear Information System (INIS)

Underwood, K.D.; Martin, S.W.; Schuck, M.L.; Scholz, A.T.

1995-01-01

The goal of this two year study was to determine if supplementation with hatchery reared steelhead trout (Oncorhynchus mykiss) and spring chinook salmon (O. tshawytscha) negatively impacted wild native bull trout (Salvelinus confluentus) through competitive interactions. Four streams with varying levels of fish supplementation activity were sampled in Southeast Washington. Tasks performed during this study were population density, relative abundance, microhabitat utilization, habitat availability, diet analysis, bull trout spawning ground surveys, radio telemetry of adult bull trout, and growth analysis. Results indicate that bull trout overlapped geographically with the supplemented species in each of the study streams suggesting competition among species was possible. Within a stream, bull trout and the supplemented species utilized dissimilar microhabitats and microhabitat utilization by each species was the same among streams suggesting that there was no shifts in microhabitat utilization among streams. The diet of bull trout and O. mykiss significantly overlapped in each of the study streams. The stream most intensely supplemented contained bull trout with the slowest growth and the non-supplemented stream contained bull trout with the fastest growth. Conversely, the stream most intensely supplemented contain steelhead with the fastest growth and the non-supplemented stream contained steelhead with the slowest growth. Growth indicated that bull trout may have been negatively impacted from supplementation, although other factors may have contributed. At current population levels, and current habitat quantity and quality, no impacts to bull trout as a result of supplementation with hatchery reared steelhead trout and spring chinook salmon were detected. Project limitations and future research recommendations are discussed

Investigations of Bull Trout (Salvelinus Confluentus), Steelhead Trout (Oncorhynchus Mykiss), and Spring Chinook Salmon (O. Tshawytscha) Interactions in Southeast Washington Streams. Final Report 1992.

Energy Technology Data Exchange (ETDEWEB)

Underwood, Keith D.

1995-01-01

The goal of this two year study was to determine if supplementation with hatchery reared steelhead trout (Oncorhynchus mykiss) and spring chinook salmon (O. tshawytscha) negatively impacted wild native bull trout (Salvelinus confluentus) through competitive interactions. Four streams with varying levels of fish supplementation activity were sampled in Southeast Washington. Tasks performed during this study were population density, relative abundance, microhabitat utilization, habitat availability, diet analysis, bull trout spawning ground surveys, radio telemetry of adult bull trout, and growth analysis. Results indicate that bull trout overlapped geographically with the supplemented species in each of the study streams suggesting competition among species was possible. Within a stream, bull trout and the supplemented species utilized dissimilar microhabitats and microhabitat utilization by each species was the same among streams suggesting that there was no shifts in microhabitat utilization among streams. The diet of bull trout and O. mykiss significantly overlapped in each of the study streams. The stream most intensely supplemented contained bull trout with the slowest growth and the non-supplemented stream contained bull trout with the fastest growth. Conversely, the stream most intensely supplemented contain steelhead with the fastest growth and the non-supplemented stream contained steelhead with the slowest growth. Growth indicated that bull trout may have been negatively impacted from supplementation, although other factors may have contributed. At current population levels, and current habitat quantity and quality, no impacts to bull trout as a result of supplementation with hatchery reared steelhead trout and spring chinook salmon were detected. Project limitations and future research recommendations are discussed.

Nutritional Status among the Children of Age Group 5-14 Years in Selected Arsenic Exposed and Non-Exposed Areas of Bangladesh.

Directory of Open Access Journals (Sweden)

Mohammad Rezaul Karim

2014-12-01

Full Text Available To assess and compare the nutritional status of children aged 5-14 years in arsenic exposed and non- exposed areas.It was a cross sectional study conducted on 600 children of age 5-14 years from arsenic exposed and non-exposed areas in Bangladesh. Designed questionnaire and check list were used for collection of data. To estimate BMI necessary anthropometric measurements of the studied children were done. Dietary intakes of the study children were assessed using 24-hours recall method.The difference of socio-economic conditions between the children of exposed area and non-exposed area was not significant. On an average the body mass index was found to be significantly (p < 0.01 lower among the children of arsenic exposed area (49% in comparison to that of children in non-exposed area (38%. Stunting (p < 0.01, wasting (p < 0.05 and underweight (p < 0.05 were significantly higher in exposed group in comparison to non-exposed group. No significant difference of nutrition intake was found between exposed and non-exposed children as well as thin and normal children.In this study children exposed to arsenic contaminated water were found to be suffered from lower nutritional status.

Sex reversal of brook trout (Salvelinus fontinalis) by 17α-methyltestosterone exposure: A serial experimental approach to determine optimal timing and delivery regimes.

Science.gov (United States)

Fatima, Shafaq; Adams, Mark; Wilkinson, Ryan

2016-12-01

Commercial culture of Brook trout (Salvelinus fontinalis) in Tasmania was partly abandoned due to sexual maturation of male fish early on during the estuarine rearing phase. Maturation adversely affects body mass, flesh quality and immunocompetency effectively. Sex reversal techniques such as the in-feed addition of a synthetic androgen have proven difficult to adapt in brook trout. An appropriate timing, duration and delivery vehicle for administration of 17α-methyltestosterone (MT) to produce phenotypic males (neomales) from genotypically female brook trout required further investigation. In this study, groups of brook trout eggs (n=1000) maintained at 9.5±0.15-10±0.14°C, were immersed in MT (400μgL -1 ) for four hours on two alternate days (two immersions/group) staggered over a two week period surrounding the hatch of embryos (control groups excluded). The groups were then split and half received MT-supplemented feed for 60days and the other a standard diet. Following an 11 month on-growing period sex phenotypes were determined by gross & histological gonad morphology. The highest proportion of male phenotypes (75%) was found in fish immersed six and four days pre-hatch and subsequently fed a normal diet. Fish fed a MT supplemented diet and immersed in MT showed significantly higher proportions of sterile fish. These data indicate that a pre-hatch immersion-only regime (4-6days pre-hatch at 9.5°C) should be pursued as a target for optimization studies to further refine the effective concentration and duration of exposure to MT for the successful production of neo-male brook trout. Copyright © 2016 Elsevier B.V. All rights reserved.

Exotic "Gill Lice" Species (Copepoda: Lernaeopodidae: Salmincola SPP.) Infect Rainbow Trout (Oncorhynchus mykiss) and Brook Trout (Salvelinus fontinalis) in the Southeastern United States.

Science.gov (United States)

Ruiz, Carlos F; Rash, Jacob M; Besler, Doug A; Roberts, Jackson R; Warren, Micah B; Arias, Cova R; Bullard, Stephen A

2017-08-01

Salmincola californiensis infected 25 of 31 (prevalence 0.8; intensity 2-35 [mean 6.6 ± standard deviation 7.7; n = 25]) rainbow trout, Oncorhynchus mykiss, from a private trout farm connected to the Watauga River, North Carolina. Salmincola edwardsii infected all of 9 (1.0; 2-43 [9.3 ± 13.0; 9]) brook trout, Salvelinus fontinalis, from Big Norton Prong, a tributary of the Little Tennessee River, North Carolina. Both lernaeopodids are well-known salmonid pathogens, but neither is native to, nor has been previously taxonomically confirmed from, the southeastern United States. Herein, we (1) use light and scanning electron microscopy to identify and provide supplemental morphological observations of these lernaeopodids, (2) furnish complementary molecular sequence data from the 28S rDNA (28S), and (3) document the pathological effects of gill infections. We identified and differentiated these lernaeopodids by the second antenna (exopod tip with large [S. californiensis] vs. slender [S. edwardsii] spines; endopod terminal segment with subequal ventral processes shorter than [S. californiensis] vs. longer than or equal to [S. edwardsii] dorsal hook), maxilliped palp (length typically ≤1/3 [S. californiensis] vs. 1/3-1/2 [S. edwardsii] subchela length exclusive of claw), and bulla (sub-circular and concave on manubrium's side [S. californiensis] vs. non-stellate [S. edwardsii]). Analysis of the 28S rDNA sequences confirmed our taxonomic assignments as demonstrated by 100% sequence similarity among the sympatric, morphologically-conspecific isolates. Histopathology revealed focal gill epithelial hyperplasia, obstruction of interlamellar water channels, lamellar fusion, and crypting of gill filaments. High intensity infections by either lernaeopodid are surveillance-worthy because they are potentially pathogenic to trout in the southeastern United States.

Disposal of tritium-exposed metal hydrides

International Nuclear Information System (INIS)

Nobile, A.; Motyka, T.

1991-01-01

A plan has been established for disposal of tritium-exposed metal hydrides used in Savannah River Site (SRS) tritium production or Materials Test Facility (MTF) R ampersand D operations. The recommended plan assumes that the first tritium-exposed metal hydrides will be disposed of after startup of the Solid Waste Disposal Facility (SWDF) Expansion Project in 1992, and thus the plan is consistent with the new disposal requiremkents that will be in effect for the SWDF Expansion Project. Process beds containing tritium-exposed metal hydride powder will be disposed of without removal of the powder from the bed; however, disposal of tritium-exposed metal hydride powder that has been removed from its process vessel is also addressed

Investigations of bull trout (Salvelinus confluentus), steelhead trout (Oncorhynchus mykiss), and spring chinook salmon (O. tshawytscha) interactions in Southeast Washington streams. Final report 1992; FINAL

International Nuclear Information System (INIS)

Underwood, K.D.; Martin, S.W.; Schuck, M.L.; Scholz, A.T.

1995-01-01

The goal of this two year study was to determine if supplementation with hatchery reared steelhead trout (Oncorhynchus mykiss) and spring chinook salmon (O. tshawytscha) negatively impacted wild native bull trout (Salvelinus confluentus) through competitive interactions. Four streams with varying levels of fish supplementation activity were sampled in Southeast Washington. Tasks performed during this study were population density, relative abundance, microhabitat utilization, habitat availability, diet analysis, bull trout spawning ground surveys, radio telemetry of adult bull trout, and growth analysis. Results indicate that bull trout overlapped geographically with the supplemented species in each of the study streams suggesting competition among species was possible. Within a stream, bull trout and the supplemented species utilized dissimilar microhabitats and microhabitat utilization by each species was the same among streams suggesting that there was no shifts in microhabitat utilization among streams. The diet of bull trout and O. mykiss significantly overlapped in each of the study streams. The stream most intensely supplemented contained bull trout with the slowest growth and the non-supplemented stream contained bull trout with the fastest growth. Conversely, the stream most intensely supplemented contain steelhead with the fastest growth and the non-supplemented stream contained steelhead with the slowest growth. Growth indicated that bull trout may have been negatively impacted from supplementation, although other factors may have contributed. At current population levels, and current habitat quantity and quality, no impacts to bull trout as a result of supplementation with hatchery reared steelhead trout and spring chinook salmon were detected. Project limitations and future research recommendations are discussed

9 CFR 78.8 - Brucellosis exposed cattle.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Brucellosis exposed cattle. 78.8... Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.8 Brucellosis exposed cattle. Brucellosis exposed cattle may be moved interstate only as follows: (a) Movement to recognized slaughtering...

Leukemias in the progeny of exposed parents

International Nuclear Information System (INIS)

Kosenko, M.M.; Gudkova, N.V.

1996-01-01

The purpose of this study was to assess the incidence of leukemias among the progeny of exposed parents. The parents were exposed as a result of discharge of radioactive waste from the Mayak atomic plant into the Techa river in the Southern Urals. The doses per parents gonads, ranging from 0.035 to 1.27 Sv, were due to external exposure in 1950-1956 and to incorporation of Cs-137. Nine cases with leukemia and four with lympohoma were recorded in 13.500 antenatally exposed subjects and descendants of exposed parents over the period of 1950 to 1988. The leukemia morbidity index for the progeny of exposed parents was 2.51, which virtually not statistically differ from that in control group. Refs. 7, figs. 3, tabs. 3

Spatial and temporal distribution of bull trout (Salvelinus confluentus)-size fish near the floating surface collector in the North Fork Reservoir, Oregon, 2016

Science.gov (United States)

Adams, Noah S.; Smith, Collin D.

2017-06-26

Acoustic cameras were used to assess the behavior and abundance of bull trout (Salvelinus confluentus)-size fish at the entrance to the North Fork Reservoir juvenile fish floating surface collector (FSC). The purpose of the FSC is to collect downriver migrating juvenile salmonids at the North Fork Dam, and safely route them around the hydroelectric projects. The objective of the acoustic camera component of this study was to assess the behaviors of bull trout-size fish observed near the FSC, and to determine if the presence of bull trout-size fish influenced the collection or abundance of juvenile salmonids. Acoustic cameras were deployed near the surface and floor of the entrance to the FSC. The acoustic camera technology was an informative tool for assessing abundance and spatial and temporal behaviors of bull trout-size fish near the entrance of the FSC. Bull trout-size fish were regularly observed near the entrance, with greater abundances on the deep camera than on the shallow camera. Additionally, greater abundances were observed during the hours of sunlight than were observed during the night. Behavioral differences also were observed at the two depths, with surface fish traveling faster and straighter with more directed movement, and fish observed on the deep camera generally showing more milling behavior. Modeling potential predator-prey interactions and influences using collected passive integrated transponder (PIT) -tagged juvenile salmonids proved largely unpredictable, although these fish provided relevant timing and collection information. Overall, the results indicate that bull trout-size fish are present near the entrance of the FSC, concomitant with juvenile salmonids, and their abundances and behaviors indicate that they may be drawn to the entrance of the FSC because of the abundance of prey-sized fish.

The properties degradation of exposed GFRP roof

Science.gov (United States)

Zainudin, Mohammad; Diharjo, Kuncoro; Kaavessina, Mujtahid; Setyanto, Djoko

2018-02-01

There is much consideration of roof selection as a protector of a building against the outside weather, such as lightweight, strong stiff, corrosion resistant and guarantee for the availability of products. Based on these considerations, glass fiber reinforced polymer (GFRP) roof is a roof which can fulfill the requirement. The objective of this research is to investigate the degradation of physical and mechanical properties of GFRP roof exposed in outside weather. This GFRP roof composite was produced using a sheet molding compound (SMC) supplied by PT Intec Persada, Tangerang, Indonesia. There are two kinds GFRP roofs evaluated in this research that are GFRP roof exposed within 7 years and new GFRP roof that has not been exposed. The GFRP roofs were cut manually for preparing the specimens for hardness test, tensile test, SEM and FTIR test. The results show that the GFRP roof exposed within 7 years had the degradation of properties compared to the new GFRP roof. The exposed GFRP roof had lower strength and hardness compared to the new GFRP roof. The SEM observation indicates that exposed GFRP roof had the debonding of fiber on the surface, and in contrast, there are no debonding of fiber in the new GFRP roof surface. It can be recommended that the exposed GFRP roof may be repaired to enhance its performance and can re-increase its properties using the coating.

Genetic diversity of wild and hatchery lake trout populations: Relevance for management and restoration in the Great Lakes

Science.gov (United States)

Page, K.S.; Scribner, K.T.; Burnham-Curtis, M.

2004-01-01

The biological diversity of lake trout Salvelinus namaycush in the upper Great Lakes was historically high, consisting of many recognizable morphological types and discrete spawning populations. During the 1950s and 1960s, lake trout populations were extirpated from much of the Great Lakes primarily as a result of overfishing and predation by the parasitic sea lamprey Petromyzon marinus. Investigations of how genetic diversity is partitioned among remnant wild lake trout populations and hatchery broodstocks have been advocated to guide lake trout management and conservation planning. Using microsatellite genetic markers, we estimated measures of genetic diversity and the apportionment of genetic variance among 6 hatchery broodstocks and 10 wild populations representing three morphotypes (lean, humper, and siscowet). Analyses revealed that different hatchery broodstocks and wild populations contributed disproportionally to the total levels of genetic diversity. The genetic affinities of hatchery lake trout reflected the lake basins of origin of the wild source populations. The variance in allele frequency over all sampled extant wild populations was apportioned primarily on the basis of morphotype (??MT = 0.029) and secondarily among geographically dispersed populations within each morphotype (??ST = 0.024). The findings suggest that the genetic divergence reflected in recognized morphotypes and the associated ecological and physiological specialization occurred prior to the partitioning of large proglacial lakes into the Great Lakes or as a consequence of higher contemporary levels of gene flow within than among morphotypes. Information on the relative contributions of different broodstocks to total gene diversity within the regional hatchery program can be used to prioritize the broodstocks to be retained and to guide future stocking strategies. The findings highlight the importance of ecological and phenotypic diversity in Great Lakes fish communities and

Boll weevil eradication: a model for sea lamprey control?

Science.gov (United States)

Smith, James W.; Swink, William D.

2003-01-01

Invasions of boll weevil (Anthonomus grandis) into the United States and sea lamprey (Petromyzon marinus) into the Great Lakes were similar in many ways. Important species (American cotton, Gossypium hirsutum, and lake trout, Salvelinus namaycush) and the industries they supported were negatively affected. Initial control efforts were unsuccessful until pesticides and application technologies were developed. For boll weevils, controls relying on pesticides evolved into an integrated program that included recommended farming practices and poisoned baits. However, the discovery of a boll weevil sex pheromone in 1964 allowed adoption of an ongoing program of eradication. Despite opposition over concept and cost, insecticides, pheromone traps, poisoned baits, and approved farming practices were used to eradicate boll weevils from Virginia, North Carolina, South Carolina, Georgia, Florida, and Alabama by 1999. Using the working back approach along the path of the original invasion, eradication was nearly completed by 2002 in Mississippi and eradication programs were underway in Arkansas, Tennessee, Oklahoma, Louisiana, and parts of Texas. Insecticide use for cotton production decreased 50 to 90%, and cotton yields and farm income increased an average of 78 kg/ha and $190 U.S./ha in areas where boll weevils were eradicated. For sea lampreys, integrated management uses lampricides, barriers to migration, trapping, and release of sterilized males. Although sea lamprey eradication is not currently feasible, recent research on larval and sex pheromones might provide the tools to make it possible. A successful eradication program for sea lampreys starting in Lake Superior and expanding to the lower Great Lakes would ultimately provide huge ecological and economic benefits by eliminating lampricide applications, removing barriers that block teleost fishes, and facilitating the recovery of lake trout. Should the opportunity arise, the concept of sea lamprey eradication should

Effectiveness of a refuge for Lake Trout in Western Lake Superior II: Simulation of future performance

Science.gov (United States)

Akins, Andrea L; Hansen, Michael J.; Seider, Michael J.

2015-01-01

Historically, Lake Superior supported one of the largest and most diverse Lake Trout Salvelinus namaycush fisheries in the Laurentian Great Lakes, but Lake Trout stocks collapsed due to excessive fishery exploitation and predation by Sea Lampreys Petromyzon marinus. Lake Trout stocking, Sea Lamprey control, and fishery regulations, including a refuge encompassing Gull Island Shoal (Apostle Islands region), were used to enable recovery of Lake Trout stocks that used this historically important spawning shoal. Our objective was to determine whether future sustainability of Lake Trout stocks will depend on the presence of the Gull Island Shoal Refuge. We constructed a stochastic age-structured simulation model to assess the effect of maintaining the refuge as a harvest management tool versus removing the refuge. In general, median abundances of age-4, age-4 and older (age-4+), and age-8+ fish collapsed at lower instantaneous fishing mortality rates (F) when the refuge was removed than when the refuge was maintained. With the refuge in place, the F that resulted in collapse depended on the rate of movement into and out of the refuge. Too many fish stayed in the refuge when movement was low (0–2%), and too many fish became vulnerable to fishing when movement was high (≥22%); thus, the refuge was more effective at intermediate rates of movement (10–11%). With the refuge in place, extinction did not occur at any simulated level of F, whereas refuge removal led to extinction at all combinations of commercial F and recreational F. Our results indicate that the Lake Trout population would be sustained by the refuge at all simulated F-values, whereas removal of the refuge would risk population collapse at much lower F (0.700–0.744). Therefore, the Gull Island Shoal Refuge is needed to sustain the Lake Trout population in eastern Wisconsin waters of Lake Superior.

Ecological factors affecting Rainbow Smelt recruitment in the main basin of Lake Huron, 1976-2010

Science.gov (United States)

O'Brien, Timothy P.; Taylor, William W.; Roseman, Edward F.; Madenjian, Charles P.; Riley, Stephen C.

2014-01-01

Rainbow Smelt Osmerus mordax are native to northeastern Atlantic and Pacific–Arctic drainages and have been widely introduced throughout North America. In the Great Lakes region, Rainbow Smelt are known predators and competitors of native fish and a primary prey species in pelagic food webs. Despite their widespread distribution, importance as a prey species, and potential to negatively interact with native fish species, there is limited information concerning stock–recruitment relationships for Rainbow Smelt. To better understand recruitment mechanisms, we evaluated potential ecological factors determining recruitment dynamics for Rainbow Smelt in Lake Huron using data from bottom trawl catches. We specifically evaluated influence of stock size, environmental factors (water temperature, lake levels, and precipitation), and salmonine predation on the production of age-0 recruits from 1976 to 2010. Rainbow Smelt recruitment was negatively related to stock size exceeding 10 kg/ha, indicating that compensatory, density-dependent mortality from cannibalism or intraspecific competition was an important factor related to the production of age-0 recruits. Recruitment was positively related to spring precipitation suggesting that the amount of stream-spawning habitat as determined by precipitation was important for the production of strong Rainbow Smelt recruitment. Additionally, density of age-0 Rainbow Smelt was positively related to Lake Trout Salvelinus namaycush abundance. However, spawning stock biomass of Rainbow Smelt, which declined substantially from 1989 to 2010, was negatively associated with Lake Trout catch per effort suggesting predation was an important factor related to the decline of age-2 and older Rainbow Smelt in Lake Huron. As such, we found that recruitment of Rainbow Smelt in Lake Huron was regulated by competition with or cannibalism by older conspecifics, spring precipitation influencing stream spawning habitats, and predation by Lake Trout on

A Lota lota consumption: Trophic dynamics of nonnative Burbot in a valuable sport fishery

Science.gov (United States)

Klobucar, Stephen L.; Saunders, W. Carl; Budy, Phaedra

2016-01-01

Unintentional and illegal introductions of species disrupt food webs and threaten the success of managed sport fisheries. Although many populations of Burbot Lota lota are declining in the species’ native range, a nonnative population recently expanded into Flaming Gorge Reservoir (FGR), Wyoming–Utah, and threatens to disrupt predator–prey interactions within this popular sport fishery. To determine potential impacts on sport fishes, especially trophy Lake Trout Salvelinus namaycush, we assessed the relative abundance of Burbot and quantified the potential trophic or food web impacts of this population by using diet, stable isotope, and bioenergetic analyses. We did not detect a significant potential for food resource competition between Burbot and Lake Trout (Schoener’s overlap index = 0.13), but overall consumption by Burbot likely affects other sport fishes, as indicated by our analyses of trophic niche space. Diet analyses suggested that crayfish were important diet items across time (89.3% of prey by weight in autumn; 49.4% in winter) and across Burbot size-classes (small: 77.5% of prey by weight; medium: 76.6%; large: 39.7%). However, overall consumption by Burbot increases as water temperatures cool, and fish consumption by Burbot in FGR was observed to increase during winter. Specifically, large Burbot consumed more salmonids, and we estimated (bioenergetically) that up to 70% of growth occurred in late autumn and winter. Further, our population-wide consumption estimates indicated that Burbot could consume up to double the biomass of Rainbow Trout Oncorhynchus mykiss stocked annually (>1.3 × 105 kg; >1 million individuals) into FGR. Overall, we provide some of the first information regarding Burbot trophic interactions outside of the species’ native range; these findings can help to inform the management of sport fisheries if Burbot range expansion occurs elsewhere.

Decline of shortjaw cisco in Lake Superior: the role of overfishing and risk of extinction

Science.gov (United States)

Bronte, Charles R.; Hoff, Michael H.; Gorman, Owen T.; Thogmartin, Wayne E.; Schneeberger, Philip J.; Todd, Thomas N.

2010-01-01

Recent reviews have further documented the decline of the shortjaw cisco Coregonus zenithicus in Lake Superior. This fish was the most abundant deepwater cisco species in Lake Superior in the early 1920s but presently makes up less than 1% of all deepwater ciscoes (i.e., including shortjaw cisco, bloater C. hoyi, and kiyi C. kiyi) captured in biological surveys. Directed overfishing of deepwater cisco species during the 1930s and again during the mid-1960s and 1970s has been suggested as the cause of the shortjaw cisco's demise. In this paper, we re-examined the overfishing hypothesis by using historical and recent survey data to estimate the proportion of the historical commercial fishery landings that comprised shortjaw ciscoes. We developed time series of estimated harvest and relative abundance for all statistical districts in Michigan waters of Lake Superior during 1929–1996, for which aggregate catch and effort data were available but not previously examined. The spatial distribution of the fishery and the relationships of catch to fishing effort were examined for evidence of overfishing. Our analysis suggested that directed overfishing was probably not the cause of shortjaw cisco demise, as this species appeared to be declining in all statistical districts regardless of the intensity of the fishery. A count-based population viability analysis indicated that quasi-extinction of the shortjaw cisco is highly probable in the near future. We propose an alternative hypothesis based on the decline of Lake Superior's keystone predator, the lake trout Salvelinus namaycush, which resulted in an expansion of the population of its principal prey, the cisco C. artedi, due to release from predation pressure. Competitive or predation interactions between the cisco and shortjaw cisco may be more likely explanations for the demise of the latter species.

Comparison of three nonlinear models to describe long-term tag shedding by lake trout

Science.gov (United States)

Fabrizio, Mary C.; Swanson, Bruce L.; Schram, Stephen T.; Hoff, Michael H.

1996-01-01

We estimated long-term tag-shedding rates for lake trout Salvelinus namaycush using two existing models and a model we developed to account for the observed permanence of some tags. Because tag design changed over the course of the study, we examined tag-shedding rates for three types of numbered anchor tags (Floy tags FD-67, FD-67C, and FD-68BC) and an unprinted anchor tag (FD-67F). Lake trout from the Gull Island Shoal region, Lake Superior, were double-tagged, and subsequent recaptures were monitored in annual surveys conducted from 1974 to 1992. We modeled tag-shedding rates, using time at liberty and probabilities of tag shedding estimated from fish released in 1974 and 1978–1983 and later recaptured. Long-term shedding of numbered anchor tags in lake trout was best described by a nonlinear model with two parameters: an instantaneous tag-shedding rate and a constant representing the proportion of tags that were never shed. Although our estimates of annual shedding rates varied with tag type (0.300 for FD-67, 0.441 for FD-67C, and 0.656 for FD-68BC), differences were not significant. About 36% of tags remained permanently affixed to the fish. Of the numbered tags that were shed (about 64%), two mechanisms contributed to tag loss: disintegration and dislodgment. Tags from about 11% of recaptured fish had disintegrated, but most tags were dislodged. Unprinted tags were shed at a significant but low rate immediately after release, but the long-term, annual shedding rate of these tags was only 0.013. Compared with unprinted tags, numbered tags dislodged at higher annual rates; we hypothesized that this was due to the greater frictional drag associated with the larger cross-sectional area of numbered tags.

Analysis of early mortality rates of survivors exposed within Japanese wooden houses in Hiroshima by exposed distance

International Nuclear Information System (INIS)

Hayakawa, Norihiko; Munaka, Masaki; Kurihara, Minoru; Ohkita, Takeshi.

1986-01-01

Mortality for 3,215 A-bomb survivors who were exposed in Japanese wooden houses at ≤ 1,300 m from the hypocenter on August 6, 1945 was examined. An overall mortality was 51 % (1,640/3,215 survivors) within 61 days after the exposure. According to the distance from the hypocenter, it was 100 % in A-bomb survivors exposed at ≤ 600 m, and 20 % in those exposed between 1,201 m and 1,300 m. The mortality decreased with increasing the distance from the hypocenter. In conjunction with the duration after the exposure and the distance from the hypocenter, the mortality was 100 % 12 days after the exposure in survivors exposed at ≤ 600 m. In survivors exposed at > 800 m, the mortality tended to be higher two weeks after the exposure than immediately after that. The distance from the hypocenter causing 50 per cent mortality was estimated to be 1,026 m from August 6 to October 5; 1,002 m from August 6 to September 10; 887 m from August 7 to September 10; and 867 m from August 20 to September 16. However, these figures were probably lower than the real mortality rates, since no information was available when whole family died. (Namekawa, K.)

[A survey of occupational health among polyether-exposed workers].

Science.gov (United States)

Fu, Xu-ying; Yu, Bin; Zhang, Chun-ping; Zheng, Guan-hua; Bai, Lan; Zhang, Pan-pan

2013-06-01

To investigate the occupational health of the workers simultaneously exposed to acrylonitrile, epoxyethane, epoxypropane, and styrene. A questionnaire survey was conducted in 70 front-line workers simultaneously exposed to acrylonitrile, epoxyethane, epoxypropane, and styrene (exposure group) and 50 managers (control group) in a polyether manufacturer; in addition, air monitoring at workplace and occupational health examination were also performed. The obtained data were analyzed. The female workers in exposure group and the spouses of male workers in exposure group had significantly higher spontaneous abortion rates than their counterparts in control group (P polyether-exposed working years had significantly higher mean levels of DNA damage than the control group (P polyether-exposed working years and those with not less than 20 polyether-exposed working years had significantly higher mean micronucleus rates than the control group (P polyether-exposed working years (P > 0.05); the workers with not less than 5 and less than 20 polyether-exposed working years and workers with not less than 20 polyether-exposed working years had significantly higher mean micronucleus rates than those with less than 5 polyether-exposed working years (P polyether manufacturer.

Proximally exposed A-bomb survivors. 2

International Nuclear Information System (INIS)

Kamada, Nanao

1992-01-01

Methods for observing chromosomes can be chronologically divided into the era of non-differential staining technique (1962-1975) and the era of differential staining method (since 1976). This paper reviews the literature of chromosomal aberrations in bone marrow cells found in the two eras. Findings during the era of 1962-1975 include the frequency of chromosomal aberrations in bone marrow cells, comparison of chromosomal aberrations in bone marrow cells and T lymphocytes, and annual variation of chromosomal aberrations. The frequency of chromosomal aberrations was high in proximally exposed A-bomb survivors (90.5% and 52.6% in A-bomb survivors exposed within 500 m and at 501-1,000 m, respectively); on the contrary, it was low in those exposed far from 1,000 m (6.2% or less). The frequency of chromosomal aberrations in bone marrow cells was lower than that in T lymphocytes (21.5% vs 27.1% in those exposed within 500 m and 14.1% vs 23% in those exposed at 501-1,000 m). Annual analysis for chromosomal aberrations has shown the somewhat dependence upon medullary hematopoiesis and virus infection. The advent of differential staining technique since 1976 has made it possible to clarify the type of chromosomal aberrations and site of breakage. Of 710 bone marrow cells taken from 13 A-bomb survivors exposed within 1,000 m, 121 cells (from 11 A-bomb survivors) exhibited chromosomal aberrations. In differential staining analysis, all 121 cells but one were found to be of stable type, such as translocation and inversion. Furthermore, the site of breakage was found to be non-randomly distributed. Analysis of chromosomal aberrations in bone marrow cells has advantages of reflecting dynamic condition of these cells and determining gradual progression into leukemia. (N.K.)

Self-reported hearing performance in workers exposed to solvents

Directory of Open Access Journals (Sweden)

Adrian Fuente

2013-02-01

Full Text Available OBJECTIVE: To compare hearing performance relating to the peripheral and central auditory system between solvent-exposed and non-exposed workers. METHODS: Forty-eight workers exposed to a mixture of solvents and 48 non-exposed control subjects of matched age, gender and educational level were selected to participate in the study. The evaluation procedures included: pure-tone audiometry (500 - 8,000 Hz, to investigate the peripheral auditory system; the Random Gap Detection test, to assess the central auditory system; and the Amsterdam Inventory for Auditory Disability and Handicap, to investigate subjects' self-reported hearing performance in daily-life activities. A Student t test and analyses of covariance (ANCOVA were computed to determine possible significant differences between solvent-exposed and non-exposed subjects for the hearing level, Random Gap Detection test and Amsterdam Inventory for Auditory Disability and Handicap. Pearson correlations among the three measures were also calculated. RESULTS: Solvent-exposed subjects exhibited significantly poorer hearing thresholds for the right ear than non-exposed subjects. Also, solvent-exposed subjects exhibited poorer results for the Random Gap Detection test and self-reported poorer listening performance than non-exposed subjects. Results of the Amsterdam Inventory for Auditory Disability and Handicap were significantly correlated with the binaural average of subject pure-tone thresholds and Random Gap Detection test performance. CONCLUSIONS: Solvent exposure is associated with poorer hearing performance in daily life activities that relate to the function of the peripheral and central auditory system.

Survival of Spores of Trichoderma longibrachiatum in Space: data from the Space Experiment SPORES on EXPOSE-R

Science.gov (United States)

Neuberger, Katja; Lux-Endrich, Astrid; Panitz, Corinna

2015-01-01

In the space experiment `Spores in artificial meteorites' (SPORES), spores of the fungus Trichoderma longibrachiatum were exposed to low-Earth orbit for nearly 2 years on board the EXPOSE-R facility outside of the International Space Station. The environmental conditions tested in space were: space vacuum at 10-7-10-4 Pa or argon atmosphere at 105 Pa as inert gas atmosphere, solar extraterrestrial ultraviolet (UV) radiation at λ > 110 nm or λ > 200 nm with fluences up to 5.8 × 108 J m-2, cosmic radiation of a total dose range from 225 to 320 mGy, and temperature fluctuations from -25 to +50°C, applied isolated or in combination. Comparable control experiments were performed on ground. After retrieval, viability of spores was analysed by two methods: (i) ethidium bromide staining and (ii) test of germination capability. About 30% of the spores in vacuum survived the space travel, if shielded against insolation. However, in most cases no significant decrease was observed for spores exposed in addition to the full spectrum of solar UV irradiation. As the spores were exposed in clusters, the outer layers of spores may have shielded the inner part. The results give some information about the likelihood of lithopanspermia, the natural transfer of micro-organisms between planets. In addition to the parameters of outer space, sojourn time in space seems to be one of the limiting parameters.

Contaminations of inner surface of magnesium fluoride windows in the `Expose-R' experiment on the International Space Station

Science.gov (United States)

Skurat, V. E.

2017-10-01

A series of experiments was carried out previously on board of the International Space Station in `EXPOSE-R', a multi-user expose facility, provided by European Space Agency attached to the external surface of the Russian Segment. In one experiment, spores of microorganisms and species of higher plant seeds, in heat-sealed polymer bags were irradiated by solar radiation passed through MgF2 windows in a high space vacuum. After sample exposure, it was found that in many cases the inner surfaces of windows were contaminated. Analysis of the contamination revealed the presence of chemical groups CH2, CH3, NH, OH, C═O, Si-CH3 (Demets et al. in 2015). Their presence in deposits was explained by photofixation of gaseous precursors - some of the vapours of glues and additives in polymeric materials in the core facility of `Expose-R'. Carbon-, oxygen- and silicon-containing groups may be deposited from outer intrinsic atmosphere. This atmosphere is connected with sample compartments and core facility. However, the presence of NH groups on inner surfaces of windows was not expected. This paper shows that the process responsible for carbon-, nitrogen- and oxygen-containing group formation can be a photopolymerization of caprolactam, which is released from the outer Nylon 6 layer of polymer bags under Solar vacuum ultraviolet radiation.

9 CFR 78.23 - Brucellosis exposed bison.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Brucellosis exposed bison. 78.23... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.23 Brucellosis exposed bison...

9 CFR 78.32 - Brucellosis exposed swine.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Brucellosis exposed swine. 78.32... AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS BRUCELLOSIS Restrictions on Interstate Movement of Swine Because of Brucellosis § 78.32 Brucellosis exposed swine. (a...

UDS in lymphocytes of occupationally radiation exposed persons

International Nuclear Information System (INIS)

Tuschl, H.; Kovac, R.

1982-01-01

To determine a possible effect of low dose radiation on DNA repair processes, peripheral lymphocytes of mine workers exposed to 222 Rn in the thermal gallery of Badgastein (Austria) and employees of the Austrian Research Centre Seibersdorf, exposed to varying doses of gamma radiation, were investigated. The capacity for unscheduled DNA synthesis (UDS) induced by in vitro UV irradiation was measured by autoradiography of isolated lymphocytes of exposed persons and unexposed controls. In all 222 Rn-exposed mine workers a significant increase of UDS above control values could be observed. Gamma irradiation 31 mrad had a significant effect on UDS, indicating a stimulation of DNA repair capability by chronic low dose exposure. (Author)

Assessing the impacts of river regulation on native bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarkii lewisi) habitats in the upper Flathead River, Montana, USA

Science.gov (United States)

Muhlfeld, Clint C.; Jones, Leslie A.; Kotter, D.; Miller, William J.; Geise, Doran; Tohtz, Joel; Marotz, Brian

2012-01-01

Hungry Horse Dam on the South Fork Flathead River, Montana, USA, has modified the natural flow regimen for power generation, flood risk management and flow augmentation for anadromous fish recovery in the Columbia River. Concern over the detrimental effects of dam operations on native resident fishes prompted research to quantify the impacts of alternative flow management strategies on threatened bull trout (Salvelinus confluentus) and westslope cutthroat trout (Oncorhynchus clarkii lewisi) habitats. Seasonal and life‐stage specific habitat suitability criteria were combined with a two‐dimensional hydrodynamic habitat model to assess discharge effects on usable habitats. Telemetry data used to construct seasonal habitat suitability curves revealed that subadult (fish that emigrated from natal streams to the river system) bull trout move to shallow, low‐velocity shoreline areas at night, which are most sensitive to flow fluctuations. Habitat time series analyses comparing the natural flow regimen (predam, 1929–1952) with five postdam flow management strategies (1953–2008) show that the natural flow conditions optimize the critical bull trout habitats and that the current strategy best resembles the natural flow conditions of all postdam periods. Late summer flow augmentation for anadromous fish recovery, however, produces higher discharges than predam conditions, which reduces the availability of usable habitat during this critical growing season. Our results suggest that past flow management policies that created sporadic streamflow fluctuations were likely detrimental to resident salmonids and that natural flow management strategies will likely improve the chances of protecting key ecosystem processes and help to maintain and restore threatened bull trout and westslope cutthroat trout populations in the upper Columbia River Basin.

To be a worker (exposed?) or not to be a worker (exposed?) that is the question

International Nuclear Information System (INIS)

Ammerich, M.

2008-01-01

The notion of personnel is detailed in this article in order to know exactly what personnel is considered as exposed and what radiation doses are under this term. The regulatory texts are studied in different articles of the French law and show that different kind of exposed personnel are considered. The definitions are varying with the notion of risk, of radiation doses and the work itself. This article asks for a better and more precise definition that will help the actors of radiation protection. (N.C.)

Fire exposed aluminium structures

NARCIS (Netherlands)

Maljaars, J.; Fellinger, J.E.J.; Soetens, F.

2005-01-01

Material properties and mechanical response models for fire design of steel structures are based on extensive research and experience. Contrarily, the behaviour of aluminium load bearing structures exposed to fire is relatively unexplored. This article gives an overview of physical and mechanical

Bull trout (Salvelinus confluentus) movement in relation to water temperature, season, and habitat features in Arrowrock Reservoir, Idaho, 2012

Science.gov (United States)

Maret, Terry R.; Schultz, Justin E.

2013-01-01

Acoustic telemetry was used to determine spring to summer (April–August) movement and habitat use of bull trout (Salvelinus confluentus) in Arrowrock Reservoir (hereafter “Arrowrock”), a highly regulated reservoir in the Boise River Basin of southwestern Idaho. Water management practices annually use about 86 percent of the reservoir water volume to satisfy downstream water demands. These practices might be limiting bull trout habitat and movement patterns. Bull trout are among the more thermally sensitive coldwater species in North America, and the species is listed as threatened throughout the contiguous United States under the Endangered Species Act. Biweekly water-temperature and dissolved-oxygen profiles were collected by the Bureau of Reclamation at three locations in Arrowrock to characterize habitat conditions for bull trout. Continuous streamflow and water temperature also were measured immediately upstream of the reservoir on the Middle and South Fork Boise Rivers, which influence habitat conditions in the riverine zones of the reservoir. In spring 2012, 18 bull trout ranging in total length from 306 to 630 millimeters were fitted with acoustic transmitters equipped with temperature and depth sensors. Mobile boat tracking and fixed receivers were used to detect released fish. Fish were tagged from March 28 to April 20 and were tracked through most of August. Most bull trout movements were detected in the Middle Fork Boise River arm of the reservoir. Fifteen individual fish were detected at least once after release. Water surface temperature at each fish detection location ranged from 6.0 to 16.2 degrees Celsius (°C) (mean=10.1°C), whereas bull trout body temperatures were colder, ranging from 4.4 to 11.6°C (mean=7.3°C). Bull trout were detected over deep-water habitat, ranging from 8.0 to 42.6 meters (m) (mean=18.1 m). Actual fish depths were shallower than total water depth, ranging from 0.0 to 24.5 m (mean=6.7 m). The last bull trout was

Pulmonary function and oxidative stress in workers exposed to styrene in plastic factory: occupational hazards in styrene-exposed plastic factory workers.

Science.gov (United States)

Sati, Prakash Chandra; Khaliq, Farah; Vaney, Neelam; Ahmed, Tanzeel; Tripathi, Ashok K; Banerjee, Basu Dev

2011-11-01

Styrene is a volatile organic compound used in factories for synthesis of plastic products. The pneumotoxicity of styrene in experimental animals is known. The aim of the present study was to study the effect of styrene on lung function and oxidative stress in occupationally exposed workers in plastic factory. Thirty-four male workers, between 18 and 40 years of age, exposed to styrene for atleast 8 hours a day for more than a year were studied, while 30 age- and sex-matched healthy subjects not exposed to styrene served as controls. Assessment of lung functions showed a statistically significant reduction (p volumes, capacities (FVC, FEV(1), VC, ERV, IRV, and IC) and flow rates (PEFR, MEF(75%), and MVV) in the study group (workers) as compared to controls. Malondialdehyde (MDA) was observed to be significantly high (p < 0.05) while ferric-reducing ability of plasma (FRAP) was significantly low (p < 0.05) in styrene-exposed subjects. Reduced glutathione (GSH) level was significantly depleted in exposed subjects as compared to control group. The mean value of serum cytochrome c in styrene-exposed subjects was found to be 1.1 ng/ml (0.89-1.89) while in control its levels were under detection limit (0.05 ng/ml). It shows that styrene inhalation by workers leads to increased level of oxidative stress, which is supposed to be the cause of lung damage.

Response of exposed bark and exposed lichen to an urban area

Energy Technology Data Exchange (ETDEWEB)

Cruz, A.M.J. [Polytechnic Institute of Coimbra, Oliveira do Hospital (Portugal). Oliveira do Hospital College of Technology and Management; Freitas, M.C.; Canha, N. [URSN, Sacavem (Portugal). Inst. Tecnologico e Nuclear (ITN); Verburg, T.G.; Wolterbeek, H.T. [Technical Univ. of Delft (Netherlands). Dept. of Radiation, Radionuclides and Reactors

2011-07-01

The aim of this study is to understand emission sources of chemical elements using biomonitoring as a tool. The selected lichen and bark were respectively Parmotrema bangii and Criptomeria japonica, sampled in the pollution-free atmosphere of Azores (Sao Miguel island), Portugal, and were exposed in the courtyards of 22 basic schools of Lisbon. The exposure was from January to May 2008 and from June to October 2008 (designated through the text as winter and summer respectively). The chemical element concentrations were determined by INAA. Conductivity of the lichen samples was measured. Factor analysis (MCTTFA) was applied to winter/summer bark/lichen exposed datasets. Arsenic emission sources, soil with anthropogenic contamination, a Se source, traffic, industry, and a sea contribution, were identified. In lichens, a physiological source based on the conductivity values was found. The spatial study showed contribution of sources to specific school positioning. Conductivity values were high in summer in locations as international Lisbon airport and downtown. Lisbon is spatially influenced by marine air mass transportation. It is concluded that one air sampler in Lisbon might be enough to define the emission sources under which they are influenced. (orig.)

Serum-thyroxine levels in microwave-exposed rats

International Nuclear Information System (INIS)

Lu, S.T.; Lebda, N.; Michaelson, S.M.; Pettit, S.

1985-01-01

The nature of the response of the thyroid gland in animals exposed to microwave irradiation is controversial. Animal experimentation has contributed to the controversy because both increased and decreased thyroid functions have been reported. The thyroxine concentration in rats as representative of thyroid function in animals exposed to 2.45-GHz, 120-Hz amplitude-modulated microwaves has been studied. These studies covered a long time span; rats from two commercial sources (BS and CR) were used and subjected to different numbers of exposures, and therefore these data were evaluated for their stability. Two factors could influence in the result significantly, i.e., source of animal and number of sham exposures. Rats used in the 2-hr exposures were from two different commercial sources; rats from CR had a higher (but normal) thyroxine concentration than did rats from BS. Therefore the data of these animals were separated by commercial source for reevaluation. Instead of increased thyroxine concentration in rats exposed at 25, 30, and 40 mW/cm 2 , changes were not noted in any microwave-exposed rats. The influence of sham exposure revealed that appropriate concurrent control and specification of animal source are needed in longitudinal studies. Furthermore, statistical procedures used can greatly influence the conclusions. Thus the specificity of changes in thyroxine concentration in rats exposed to microwaves because of its sporadic occurrence and because of inconsistencies among experiments was doubted

Exposure-related effects of Pseudomonas fluorescens, strain CL145A, on coldwater, coolwater, and warmwater fish

Science.gov (United States)

Luoma, James A.; Weber, Kerry L.; Denise A. Mayer,

2015-01-01

The exposure-related effects of a commercially prepared spray-dried powder (SDP) formulation of Pseudomonas fluorescens, strain CL145A, were evaluated on coldwater, coolwater, and warmwater fish endemic to the Great Lakes and Upper Mississippi River Basins. Nine species of young-of-the-year fish were exposed to SDP for 24 hours by using continuous-flow, serial-dilution exposure systems at temperatures of 12 degrees Celsius (°C; 2 species; Oncorhynchus mykiss [rainbow trout] and Salvelinus fontinalis [brook trout]), 17 °C (3 species; Perca flavescens [yellow perch], Sander vitreus [walleye], and Acipenser fulvescens [lake sturgeon]), or 22 °C (4 species; Micropterus salmoides [largemouth bass], Micropterus dolomieu [smallmouth bass], Lepomis macrochirus [bluegill sunfish], and Ictalurus punctatus [channel catfish]).

Survey on Urinary Levels of Aflatoxins in Professionally Exposed Workers

Directory of Open Access Journals (Sweden)

Fulvio Ferri

2017-03-01

Full Text Available Feed mill workers may handle or process maize contaminated with aflatoxins (AFs. This condition may lead to an unacceptable intake of toxins deriving from occupational exposure. This study assessed the serological and urinary levels of AFs in workers exposed to potentially contaminated dusts in two mills. From March to April 2014, blood and urine samples were collected, on Monday and Friday morning of the same working week from 29 exposed workers and 30 non-exposed controls. AFs (M1, G2, G1, B1, B2 and aflatoxicol (AFOH A were analyzed. Each subject filled in a questionnaire to evaluate potential food-borne exposures to mycotoxins. AFs contamination in environmental dust was measured in both plants. No serum sample was found to be positive. Seventy four percent of urine samples (73.7% revealed AFM1 presence. AFM1 mean concentration was 0.035 and 0.027 ng/mL in exposed and non-exposed workers, respectively (p = 0.432; the concentration was slightly higher in Friday’s than in Monday’s samples, in exposed workers, 0.040 versus (vs. 0.031 and non-exposed controls (0.030 vs. 0.024, p = 0.437. Environmental AFs contamination ranged from 7.2 to 125.4 µg/kg. The findings of this study reveal the presence of higher AFs concentration in exposed workers than in non-exposed controls, although these differences are to be considered consistent with random fluctuations.

Going beyond the most exposed people in a dose assessment

Energy Technology Data Exchange (ETDEWEB)

Hjerpe, Thomas; Broed, Robert [Facilia AB, Gustavslundsvaegen 151C, SE-167 51 Bromma (Sweden); Ikonen, Ari T.K. [Environmental Research and Assessment, EnviroCase, Ltd., Hallituskatu 1 D 4, FI-28 100 Pori (Finland)

2014-07-01

The dose assessment in a long-term radiation safety assessment often focus on assessing dose of a representative person to be used for determining compliance with a radiation dose constraint. This representative person is often assumed to receive a dose that is representative of the most exposed people, i.e., the more highly exposed individuals in the population. This is not always sufficient, the Finnish regulations for disposal of nuclear waste has radiation dose constraint to the most exposed people as well as for larger groups of exposed people. This work presents the methodology to assessing dose of a representative person for a larger group of exposed people as applied by Posiva in the TURVA-2012 safety case for the spent nuclear fuel disposal at Olkiluoto. In addition, annual doses from the set of biosphere calculation cases analysed in TURVA-2012 are presented and discussed. Special focus is given on explaining the differences in exposure levels and exposure routes between the estimated annual doses to representative persons for most exposed people and a larger exposed group. The results show that the annual doses to a larger group of people ranges from one to three orders of magnitude below the annual doses to the most exposed people. Furthermore, the exposure route related to food ingestion is less significant for the larger group of people compared to the most exposed people and that the exposure route related to water ingestion shows the opposite behaviour. (authors)

Temperature selection of goldfish (Carassius auratus L. ) and brook trout (Salvelinus fontinalis Mitch. ) after heterogeneous temperature acclimation

Energy Technology Data Exchange (ETDEWEB)

Mueller, R.

1977-01-01

Goldfish and brook trout were acclimated heterogeneously to temperature by exposing the head and tail simultaneously to different temperatures. The temperature selection of heterogeneously acclimated fish was tested in a vertical temperature gradient and compared to that of homogeneously acclimated fish. All fish selected temperatures essentially corresponding to the state of acclimation of their head. It is concluded that the brain acts as the main control of temperature selection in fish.

Reprocessing of nonoptimally exposed holograms

International Nuclear Information System (INIS)

Phipps, G.S.; Robertson, C.E.; Tamashiro, F.M.

1980-01-01

Two reprocessing techniques have been investigated that are capable of correcting the effects of nonoptimum optical density of photographic amplitude holograms recorded on Agfa-Gevaert type 10E75 plates. In some cases a reprocessed hologram will exhibit a diffraction efficiency even higher than that obtainable from a hologram exposed and processed to the optimum density. The SNR of the reprocessed holograms is much higher than that of the same holograms belached with cupric bromide. In some cases the SNR approaches the optimum value for a properly exposed amplitude hologram. Subjective image quality and resolution of reprocessed hologram reconstructins appear to be no different than for normal single-development holograms. Repeated reprocessing is feasible and in some cases desirable as a means of increasing diffraction efficiency

The Affect of the Space Environment on the Survival of Halorubrum Chaoviator and Synechococcus (Nageli): Data from the Space Experiment OSMO on EXPOSE-R

Science.gov (United States)

Mancinelli, R. L.

2014-01-01

We have shown using ESA's Biopan facility flown in Earth orbit that when exposed to the space environment for 2 weeks the survival rate of Synechococcus (Nageli), a halophilic cyanobacterium isolated from the evaporitic gypsum-halite crusts that form along the marine intertidal, and Halorubrum chaoviator a member of the Halobacteriaceae isolated from an evaporitic NaCl crystal obtained from a salt evaporation pond, were higher than all other test organisms except Bacillus spores. These results led to the EXPOSE-R mission to extend and refine these experiments as part of the experimental package for the external platform space exposure facility on the ISS. The experiment was flown in February 2009 and the organisms were exposed to low-Earth orbit for nearly 2 years. Samples were either exposed to solar ultraviolet (UV)-radiation (lambda is greater than 110 nm or lambda is greater than 200 nm, cosmic radiation (dosage range 225-320 mGy), or kept in darkness shielded from solar UV-radiation. Half of each of the UV-radiation exposed samples and dark samples were exposed to space vacuum and half kept at 105 pascals in argon. Duplicate samples were kept in the laboratory to serve as unexposed controls. Ground simulation control experiments were also performed. After retrieval, organism viability was tested using Molecular Probes Live-Dead Bac-Lite stain and by their reproduction capability. Samples kept in the dark, but exposed to space vacuum had a 90 +/- 5% survival rate compared to the ground controls. Samples exposed to full UV-radiation for over a year were bleached and although results from Molecular Probes Live-Dead stain suggested approximately 10% survival, the data indicate that no survival was detected using cell growth and division using the most probable number method. Those samples exposed to attenuated UV-radiation exhibited limited survival. Results from of this study are relevant to understanding adaptation and evolution of life, the future of life

Psychopharmacologic treatment of children prenatally exposed to drugs of abuse.

Science.gov (United States)

Hulvershorn, Leslie A; Schroeder, Kristen M; Wink, Logan K; Erickson, Craig A; McDougle, Christopher J

2015-05-01

This pilot study compared the pharmacologic treatment history and clinical outcomes observed in pediatric outpatients with psychiatric disorders exposed to drugs of abuse in utero to those of an age-matched, sex-matched and psychiatric disorder-matched, non-drug-exposed group. In this matched cohort study, medical records of children treated at an academic, child and adolescent psychiatry outpatient clinic were reviewed. Children with caregiver-reported history of prenatal drug exposure were compared with a non-drug-exposed control group being cared for by the same providers. Patients were rated with the Clinical Global Impressions-Severity scale (CGI-S) throughout treatment. The changes in pre-treatment and post-treatment CGI-S scores and the total number of medication trials were determined between groups. The drug-exposed group (n = 30) had a higher total number of lifetime medication trials compared with the non-drug-exposed group (n = 28) and were taking significantly more total medications, at their final assessment. Unlike the non-drug-exposed group, the drug-exposed group demonstrated a lack of clinical improvement. These results suggest that in utero drug-exposed children may be more treatment-refractory to or experience greater side effects from the pharmacologic treatment of psychiatric disorders than controls, although we cannot determine if early environment or drugs exposure drives these findings. Copyright © 2015 John Wiley & Sons, Ltd.

Exposing Latent Information in Folksonomies for Reasoning

Science.gov (United States)

2010-01-14

1.73 $.") http://www.w3.org/2006/07/SWD/ SKOS /reference/20081001/ Spiteri, L.F. (2007) "The structure and form of folksonomy tags: The road to the...Exposing Latent Information in Folksonomies for Reasoning January 14, 2010 Sponsored by Defense Advanced Research Projects Agency (DOD...DATES COVERED (From - To! 4/14/2009-12/23/2009 4. TITLE AND SUBTITLE Exposing Latent Information in Folksonomies for Reasoning Sa. CONTRACT

Genetic Alterations in Pesticide Exposed Bolivian Farmers

DEFF Research Database (Denmark)

Jørs, Erik; González, Ana Rosa; Ascarrunz, Maria Eugenia

2007-01-01

: Questionnaires were applied and blood tests taken from 81 volunteers from La Paz County, of whom 48 were pesticide exposed farmers and 33 non-exposed controls. Sixty males and 21 females participated with a mean age of 37.3 years (range 17-76). Data of exposure and possible genetic damage were collected...... and evaluated by well known statistical methods, controlling for relevant confounders. To measure genetic damage chromosomal aberrations and the comet assay analysis were performed. Results: Pesticide exposed farmers had a higher degree of genetic damage compared to the control group. The number of chromosomal......, probably related to exposure to pesticides. Due to the potentially negative long term health effects of genetic damage on reproduction and the development of cancer, preventive measures are recommended. Effective control with imports and sales, banning of the most toxic pesticides, education...

9 CFR 73.8 - Cattle infected or exposed during transit.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Cattle infected or exposed during... SCABIES IN CATTLE § 73.8 Cattle infected or exposed during transit. (a) Healthy cattle from unquarantined State exposed en route. Should healthy cattle in transit from a State not quarantined by the Secretary...

Educator Sexual Misconduct: Exposing or Causing Learners to Be Exposed to Child Pornography or Pornography

Directory of Open Access Journals (Sweden)

Susan Coetzee

2016-02-01

Full Text Available he law recognises that non-contact sexual offences can cause harm and several offences were created to regulate non-contact sexual child abuse offences. Several of these offences deal with the exposure or causing exposure of children to child pornography or pornography. Sexual grooming of children and the “Exposure or display of or causing exposure or display of child pornography or pornography to children” are criminalised in sections 18(2 and 19 of the Criminal Law (Sexual Offences and Related Matters Amendment Act 32 of 2007. And offences in relation to exposing children to disturbing, harmful and age-inappropriate materials are criminalised in sections 24A(2 and (4 of the Films and Publications Act 65 of 1996. In this article the author considered the content of the offences of “Exposure or display of or causing exposure or display of child pornography or pornography to children” in relation to the other offences dealing with exposure of children to child pornography or pornography. Benchmarked against these criminal offences the author then conceptualised exposing learners, or causing the exposure of learners to child pornography or pornography as forms of educator misconduct. The seriousness that should be attached to these forms of misconduct was considered in light of the various criminal offences. The review of the criminal offences and the forms of educator misconduct brought the ineffectiveness of current forms of serious educator misconduct to the fore. There is no form of serious misconduct that covers the transgression of educators who expose learners to child pornography or pornography that can be classified as “XX”. In conclusion a suggestion is made with regard to how a new form of serious misconduct could be worded so as to cover this gap, eg An educator must be dismissed if he or she is found guilty of – (g exposing a learner to or causing exposure of a learner to material classified as “Refused” or �

The food of the lake trout (Cristivomer namaycush namaycush) and of the lawyer (Lota maculosa) of Lake Michigan

Science.gov (United States)

Van Oosten, John; Deason, Hilary J.

1938-01-01

This paper reports on a qualitative and quantitative analysis of the contents of 4,979 lake trout stomachs (593 examined in 1930 and 1,253 collected in 1931 from southern Lake Michigan, 1,446 from northern Lake Michigan and 1,687 from Green Bay in 1932), and of a total of 1,528 lawyer stomachs (172 examined in 1930 and 734 collected in 1931 from southern Lake Michigan, 612 from northern Lake Michigan and 10 from Green Bay in 1932). The food of the trout consisted of 98 per cent by volume of fish of which Cottidae and Coregonidae were the principal constituents. Cottidae were dominant in southern Lake Michigan (72 per cent by volume), Coregonidae in northern Lake Michigan (51 per cent) but the lake shiner, Notropis atherinides, was most important in Green Bay in the spring of the year (64 per cent). The lawyer food consisted of 74 per cent by volume of fish and 26 per cent invertebrates. Dominant items were Cottidae (76 per cent by volume) in southern Lake Michigan, Coregonidae (51 per cent) and Pontoporeia (37 per cent) in northern Lake Michigan, and Percopsis (34 per cent) and Mysis (26 per cent) in Green Bay. Data are also presented on the frequency of occurrence (number of stomachs) of the food items and its variation with the sizes of the trout and lawyers, depths of water, seasons, and localities; on the number of individual fish of each species destroyed by the trout and lawyers; and on the calculated volume of the food fishes preceding digestion. The lake trout and lawyer are competitors for the same food, are both predators of the commercially important Coregonidae, and the lawyer through its consumption of invertebrates is a food competitor of the Coregonidae.

The affect of the space environment on the survival of Halorubrum chaoviator and Synechococcus (Nägeli): data from the Space Experiment OSMO on EXPOSE-R

Science.gov (United States)

Mancinelli, R. L.

2015-01-01

We have shown using ESA's Biopan facility flown in Earth orbit that when exposed to the space environment for 2 weeks the survival rate of Synechococcus (Nägeli), a halophilic cyanobacterium isolated from the evaporitic gypsum-halite crusts that form along the marine intertidal, and Halorubrum chaoviator a member of the Halobacteriaceae isolated from an evaporitic NaCl crystal obtained from a salt evaporation pond, were higher than all other test organisms except Bacillus spores. These results led to the EXPOSE-R mission to extend and refine these experiments as part of the experimental package for the external platform space exposure facility on the ISS. The experiment was flown in February 2009 and the organisms were exposed to low-Earth orbit for nearly 2 years. Samples were either exposed to solar ultraviolet (UV)-radiation (λ > 110 nm or λ > 200 nm, cosmic radiation (dosage range 225-320 mGy), or kept in darkness shielded from solar UV-radiation. Half of each of the UV-radiation exposed samples and dark samples were exposed to space vacuum and half kept at 105 pascals in argon. Duplicate samples were kept in the laboratory to serve as unexposed controls. Ground simulation control experiments were also performed. After retrieval, organism viability was tested using Molecular Probes Live-Dead Bac-Lite stain and by their reproduction capability. Samples kept in the dark, but exposed to space vacuum had a 90 +/- 5% survival rate compared to the ground controls. Samples exposed to full UV-radiation for over a year were bleached and although results from Molecular Probes Live-Dead stain suggested ~10% survival, the data indicate that no survival was detected using cell growth and division using the most probable number method. Those samples exposed to attenuated UV-radiation exhibited limited survival. Results from of this study are relevant to understanding adaptation and evolution of life, the future of life beyond earth, the potential for interplanetary

Clinical findings on in utero exposed microcephalic children

Energy Technology Data Exchange (ETDEWEB)

Tabuchi, Akira; Hirai, Tsuyoshi; Nakagawa, Shigeru; Shimada, Katsunobu; Fujito, Junro

1966-12-24

Since animal experiments have shown that microcephaly is induced by fetal exposure to radiation and microcephaly has been found in children of mothers exposed to x-ray therapy during pregnancy (Murphy et al), the main cause of microcephaly in children exposed in utero to the A-bomb is considered to be ionizing radiation. Wood et al reported the increased incidence of microcephaly and mental retardation in children exposed in utero at proximal distances which they felt could not be attributed to any other known variable. ABCC has recently concluded that the effect of in utero exposure is primarily due to the immediate effect of radiation upon the fetuses although in A-bomb exposure the physical injury to the mother due to the A-bomb cannot be completely ignored. Our survey likewise revealed an increase of microcephaly in children exposed early in pregnancy at less than 15 weeks at closer distances than 1500 m. Thus, we presume that A-bomb radiation increases the incidence of microcephaly. 16 references, 8 tables.

Animal Cruelty by Children Exposed to Domestic Violence

Science.gov (United States)

Currie, Cheryl L.

2006-01-01

Objective: The first objective of this study was to determine if children exposed to domestic violence were significantly more likely to be cruel to animals than children not exposed to violence. The second was to determine if there were significant age and gender differences between children who were and were not cruel to animals. Method: A…

Urine nickel concentrations in nickel-exposed workers.

Science.gov (United States)

Bernacki, E J; Parsons, G E; Roy, B R; Mikac-Devic, M; Kennedy, C D; Sunderman, F W

1978-01-01

Electrothermal atomic absorption spectrometry was employed for analyses of nickel concentrations in urine samples from nickel-exposed workers in 10 occupational groups and from non-exposed workers in two control groups. Mean concentrations of nickel in urine were greatest in workers who were exposed to inhalation of aerosols of soluble nickel salts (e.g., workers in nickel plating operations and in an electrolytic nickel refinery). Less marked increases in urine nickel concentrations were found in groups of metal sprayers, nickel battery workers, bench mechanics and are welders. No significant increases in mean concentrations of nickel were found in urine samples from workers who performed grinding, buffing and polishing of nickel-containing alloys or workers in a coal gasification plant who employed Raney nickel as a hydrogenation catalyst. Measurements of nickel concentrations in urine are more sensitive and practical than measurements of serum nickel concentrations for evaluation of nickel exposures in industrial workers.

Metabolic interactions between low doses of benzo[a]pyrene and tributyltin in arctic charr (salvelinus alpinus): a long-term in vivo study

International Nuclear Information System (INIS)

Padros, Jaime; Pelletier, Emilien; Ribeiro, Ciro Oliveira

2003-01-01

We have previously reported that short-term, single exposure to a high dose of tributyltin (TBT), a widely used antifouling biocide, inhibited both the in vivo metabolism and metabolic activation of the carcinogenic polycyclic aromatic hydrocarbon benzo[a]pyrene (BaP) in fish; (BaP), in turn, stimulated TBT metabolism. Here, we provide further mechanistic evidence of mutual metabolic interactions between BaP and TBT in response to long-term, repeated exposures to low doses. Juvenile Arctic charr (Salvelinus alpinus) received 10 separate ip injections (a single injection every 6 days) of BaP (3 mg/kg), TBT (0.3 mg/kg), or both in combination; control fish received corn oil vehicle only. Two days after the 2nd (Day 8), 6 th (Day 32), and 10th dose (Day 56), blood, bile, and liver samples were collected and analyzed for a suite of biomarkers. HPLC/fluorescence analysis indicated that TBT cotreatment inhibited the formation of (+)-anti-BaP diol-epoxide adducts with plasma albumin (53%, Day 8), hepatic DNA (27%, Day 32), or both albumin and globin (50 and 58%, Day 56) compared to BaP alone. This antagonistic interaction was associated with a time-dependent modulation (inhibition at Day 8, enhancement at Day 32) of both cytochrome P450 (P450)1A-mediated ethoxyresorufin O-deethylase (EROD) activity and biliary BaP metabolite formation. TBT cotreatment also inhibited (39%) the BaP-mediated induction of hepatic glutathione S-transferase (GST) activity observed at Day 8. Treatment with TBT alone increased EROD activity (60%) at Day 32, but decreased both GST activity (70 and 37%) and glutathione content (24% and 16%) at Days 32 and 56, respectively. GC/MS analysis revealed that, at Day 56, BaP cotreatment increased (200%) the levels of biliary butyltin compounds, including mono- and dibutyltin metabolites. This potentiative interaction was associated with a protective effect of BaP cotreatment against the TBT-mediated decreases in GST activity and glutathione content. The

Expose-R experiment on effects of open space condition on survivorship in dormant stages of aquatic invertebrates

Science.gov (United States)

Alekseev, Victor; Novikova, Nataliya; Levinskikh, Margarita; Sychev, Vladimir; Yusoff, Fatimah; Azuraidi, Osman

2012-07-01

Dormancy protects animals and plants in harsh environmental conditions from months up to hundred years. This phenomenon is perspective for space researches especially for interplanetary missions. Direct experiments in open space BYORYSK supported in principle the fact of survivorship of bacteria, fungi spores, seed of plants and crustacean dormant cysts. Even though the rate of survivorship in long-term treatments was low but good enough to conclude that biological invasion even to Mars is a real danger. As soon as the BYORYSK lunch was made of metal the possibility for resting stages to survive under UV treatment in vacuum without some protection was not clear. To test it an ESA and RSA equipment titled EXPOSE-R was applied. The EXPOSE-R facility was an external facility attached to the outside of the Zvezda Service Module in ISS in the end of November 2008. It had glace windows transparent for UV-radiation and possibility to measure temperature, space- and UV-radiation. Among a number of experiments requiring exposure to the open space environment it had a biological launch containing resting stages of terrestrial and aquatic organisms. These stages included dried ephippia of cladoceran Daphnia magna differentiated on size, dormant eggs of ostracode Eucypris ornate, cysts of fair-shrimp Streptocephalus torvicornis ( all from hemi desert Caspian area) and Artemis salina from salt lake Crimean populations. All dormant stages were kept in transparent to UV plastic bags placed in three layers. After about two years of exposing in open space dormant stages of 3 species A. salina, D. magna, S. torvicornis successfully survived at different scales but in second and third layers only . The highest level of survivorship was found in A. salina cysts. In preliminary land experiments that imitated land EXPOSE imitation of outside space station UV and vacuum conditions survivorship in resting eggs of D .magna, S. torvicornis and E. ornate was tested also. The total UV dose of

Evaluation of selenium in biological sample of arsenic exposed female skin lesions and skin cancer patients with related to non-exposed skin cancer patients

Energy Technology Data Exchange (ETDEWEB)

Kolachi, Nida F.; Kazi, Tasneem G., E-mail: tgkazi@yahoo.com; Wadhwa, Sham K.; Afridi, Hassan I.; Baig, Jameel A.; Khan, Sumaira; Shah, Faheem

2011-08-01

The antagonistic effects between selenium (Se) and arsenic (As) suggest that low Se status plays an important role in arsenism development. The objective of present study was to assess Se contents in biological samples of As exposed females have skin lesions and cancer with related to non-exposed skin cancer patients. The biological samples (blood and scalp hair) of As exposed group comprises, female skin cancer (ESC) patients admitted in cancer hospitals have skin lesions (ESL) and exposed referents have not both diseases (ER), belongs to As exposed area of Pakistan. For comparative purposes, age matched female skin cancerous patient (RP) and non-cancerous females (NER) belong to non-exposed areas were also selected. The As and Se in acid digests of biological samples were pre-concentrated by complexing with chelating agent (ammonium pyrrolidinedithiocarbamate), and resulted complexes were extracted into non-ionic extractant (Triton X-114), prior to analysis by electrothermal atomic absorption spectrometry. The enhancement factor of about 25 was obtained by pre-concentrating 10 mL of sample solutions. The accuracy of the optimized procedure was evaluated by using certified reference material (BCR 397) with certified values for Se and As and standard addition method at three concentration levels in real samples. No significant differences was observed (p > 0.05) when comparing the values obtained by the proposed method, added and certified values of both elements. The biological samples of ESC patients had 2-3 folds higher As and lower Se levels as compared to RP (p < 0.001). Understudied exposed referents have high level of As and lower Se contents as compared to referents subjects of non-exposed area (p < 0.01). The higher concentration of As and lower levels of Se in biological samples of cancerous patients are consisted with reported studies. - Research Highlights: {yields} Advance extraction method for the enrichment of arsenic and selenium in biological

Evaluation of selenium in biological sample of arsenic exposed female skin lesions and skin cancer patients with related to non-exposed skin cancer patients

International Nuclear Information System (INIS)

Kolachi, Nida F.; Kazi, Tasneem G.; Wadhwa, Sham K.; Afridi, Hassan I.; Baig, Jameel A.; Khan, Sumaira; Shah, Faheem

2011-01-01

The antagonistic effects between selenium (Se) and arsenic (As) suggest that low Se status plays an important role in arsenism development. The objective of present study was to assess Se contents in biological samples of As exposed females have skin lesions and cancer with related to non-exposed skin cancer patients. The biological samples (blood and scalp hair) of As exposed group comprises, female skin cancer (ESC) patients admitted in cancer hospitals have skin lesions (ESL) and exposed referents have not both diseases (ER), belongs to As exposed area of Pakistan. For comparative purposes, age matched female skin cancerous patient (RP) and non-cancerous females (NER) belong to non-exposed areas were also selected. The As and Se in acid digests of biological samples were pre-concentrated by complexing with chelating agent (ammonium pyrrolidinedithiocarbamate), and resulted complexes were extracted into non-ionic extractant (Triton X-114), prior to analysis by electrothermal atomic absorption spectrometry. The enhancement factor of about 25 was obtained by pre-concentrating 10 mL of sample solutions. The accuracy of the optimized procedure was evaluated by using certified reference material (BCR 397) with certified values for Se and As and standard addition method at three concentration levels in real samples. No significant differences was observed (p > 0.05) when comparing the values obtained by the proposed method, added and certified values of both elements. The biological samples of ESC patients had 2-3 folds higher As and lower Se levels as compared to RP (p < 0.001). Understudied exposed referents have high level of As and lower Se contents as compared to referents subjects of non-exposed area (p < 0.01). The higher concentration of As and lower levels of Se in biological samples of cancerous patients are consisted with reported studies. - Research Highlights: → Advance extraction method for the enrichment of arsenic and selenium in biological matrices

Equilibrium disorders in workers exposed to mixed solvents.

Science.gov (United States)

Giorgianni, Concetto; Tanzariello, Mariagiuseppina; De Pasquale, Domenico; Brecciaroli, Renato; Spatari, Giovanna

2018-02-06

Organic solvents cause diseases of the vestibular system. However, little is known regarding the correlation between vestibular damage and exposure to organic solvents below threshold limit values. The best measure by which to evaluate vestibular disorders is static and dynamic posturography. The aim of this study was to evaluate equilibrium disorders via static and dynamic posturography in workers without clear symptoms and exposed to low doses of mixed solvents. 200 subjects were selected. Using an Otometrics device (Madsen, Denmark), all subjects endured static and dynamic posturography testing with both eyes-open and eyes-closed conditions. Results were compared with a control group of unexposed individuals. Based on the obtained data, the following results can be drawn: (a) subjects exposed to mixtures of solvents show highly significant differences regarding all static and dynamic posturography parameters in comparison to the control group; (b) posturography testing has proven to be a valid means by which to detect subliminal equilibrium disorders in subjects exposed to solvents. We can confirm that refinery workers exposed to mixtures of solvents can present subliminal equilibrium disorders. Early diagnosis of the latter is made possible by static and dynamic posturography.

Studies on persons exposed to plutonium

International Nuclear Information System (INIS)

Voelz, G.L.; Stebbings, J.H.; Hempelmann, L.H.; Haxton, L.K.; York, D.A.

1978-01-01

The results of four studies of persons exposed, or potentially exposed, to plutonium are summarized. The studies are: a five-year update on clinical examinations and health experience of 26 Manhattan District workers heavily exposed at Los Alamos in 1944 to 1945; a 30-year mortality follow-up of 224 white male workers with plutonium body burdens of 10 nCi or more; a review of cancer mortality rates between 1950 and 1969 among Los Alamos County, New Mexico, male residents, all of whom have worked in or have lived within a few kilometers of a major plutonium plant and other nuclear facilities; and a review of cancer incidence rates between 1969 and 1974 in male residents of Los Alamos County. No excess of mortality due to any cause was observed in the 224 male subjects with the highest plutonium exposures at Los Alamos. Clinical examinations of the Manhattan District workers, whose average age in 1976 was 56 years, show them to be active persons with diseases that are not unusual for their ages. The two deaths in this group over the past 30 years have not been due to cancer. Mortality and incidence data indicate no excess of lung cancer in Los Alamos County males

Behavioural changes in mice exposed to low level microwave fields

International Nuclear Information System (INIS)

Goiceanu, C.; Gradinaru, F.; Danulescu, R.; Balaceanu, G.; Sandu, D. D.; Avadanei, O. G.

2001-01-01

The aim of our study is to point out some changes in mice behaviour due possibly to exposure to low-level microwave fields. Animals spontaneous behaviour were monitored and the exploring behaviour and motor activity were assessed. Ten selected Swiss male mice were exposed to low-level microwave fields of about 1 mW/cm 2 power density for a relatively long period of time (13 weeks), comparing to their lifetime. The exposure system consists in a transverse electromagnetic (TEM) Cell. A control lot of ten Swiss male mice was used. All twenty mice were selected to be of same age and of 202 g initial body weight. Each animal was placed in his own holder. The behaviour of the animals, from both exposed and control lots, was assessed by using a battery of three behavioural tests. The test sessions were performed every two weeks. During exposure period it was recorded a progressive but moderate loss of motor activity for both exposed and controls, probably due to weight gain and aging. Concerning exploratory activity there is a significant difference between control and exposed animals. Control mice had approximately constant performances in time. On the other hand exposed mice showed a progressive decrease in time of their exploratory ability. Motor activity of exposed animals does not seem to be affected by microwave exposure, in spite of moderate loss in time of motor activity in both lots, as long as it was recorded a quite similar evolution. The difference in performances of exposed and controls concerning exploratory activity seem to emphasise an effect of long-term low-level microwave exposure. The progressive loss in time of exploratory activity of exposed mice, in contrast with controls, could be due to the interference of microwaves with central nervous activity. (authors)

[Hepatotoxicity in healthy infants exposed to nevirapine during pregnancy].

Science.gov (United States)

Iveli, Pablo; Noguera-Julian, Antoni; Soler-Palacín, Pere; Martín-Nalda, Andrea; Rovira-Girabal, Núria; Fortuny-Guasch, Clàudia; Figueras-Nadal, Concepció

2016-01-01

The use of nevirapine in HIV-infected pregnant women is discouraged due to its potential to cause hepatotoxicity. There is limited information available on the toxicity in non-HIV infected newborn exposed to this drug during pregnancy. The aim of the study is to determine the extent of hepatotoxicity in the newborn exposed to nevirapine and HIV during pregnancy. A cross-sectional, observational, multicenter study was conducted on a cohort of healthy infants born to HIV-infected mothers, in whom the first determination of alanine aminotransferase (ALT), before 6weeks of age, was collected. Patients were allocated to 2groups according to exposure to nevirapine during pregnancy. Hepatotoxicity was rated according to the AIDS Table for Grading the Severity of Adult and Pediatric Adverse Events (DAIDS). This study included 160newborns from 159pregnancies (88exposed to nevirapine-based regimens and 71 exposed to protease inhibitors-based therapies). No cases of hepatotoxicity were observed according to the DAIDS Table for Grading. Two cases of ALT above normal values (2.8%; 95%CI: 0.3-9.8%) were observed in patients not exposed to nevirapine, and one case (1.1%; 95%CI: 0.0-6.1%) in the group exposed to nevirapine (P=.585). The lack of differences between groups suggests that highly active antiretroviral treatment regimens including nevirapine administered during pregnancy do not involve a higher risk of liver disease compared to other treatment combinations. Copyright © 2014 Elsevier España, S.L.U. y Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

Evidence that lake trout served as a buffer against sea lamprey predation on burbot in Lake Erie

Science.gov (United States)

Stapanian, M.A.; Madenjian, C.P.

2007-01-01

The population of burbot Lota lota in Lake Erie recovered during 1986–2003, mainly because of the control of sea lamprey Petromyzon marinus, which began in 1986. Burbot populations continued to grow during 1996–1998, when sea lamprey control was substantially reduced. We calculated mortality parameters for burbot in Lake Erie by estimating age at capture for 2,793 burbot caught in annual gill-net surveys of eastern Lake Erie from 1994 to 2003. Based on catch-curve analysis, annual mortality in Lake Erie during 1994–2003 was estimated as 33%. Annual mortality of the 1992 year-class of burbot was estimated as 30%. The mortality of burbot during the years of reduced sea lamprey control was not different from that during the 3 years preceding reduced control and was significantly lower than that during the entire portion of the time series in which full sea lamprey control was conducted. These results suggest that the reduction in sea lamprey control did not lead to increased burbot mortality. The catch per gill-net lift of large burbot (total length > 600 mm), the size preferred by sea lampreys, was lower than that of adult lake trout Salvelinus namaycush (age 5 and older; total length > 700 mm) before lampricide application was reduced. Although adult lake trout populations declined, the abundance of large burbot did not change during the period of reduced lampricide application. These results support a hypothesis that a healthy population of adult lake trout can serve as a buffer species, acting to reduce predation of burbot by sea lampreys when sea lamprey populations increase. Burbot attained sexual maturity at a relatively early age (3 or 4 years) and a total length (approximately 500 mm) that was smaller than the preferred prey size for sea lampreys. These characteristics and the buffering effect of the lake trout population enabled growth of the burbot population during the brief period when lamprey control was reduced.

Mercury Dynamics in Aquatic Food Webs of the Finger Lakes, New York

Science.gov (United States)

Cleckner, L.; Razavi, N. R.; Halfman, J. D.; Cushman, S. F.; Foust, J.; Gilman, B.

2016-12-01

Mercury (Hg) contamination of fish is a global concern due to the deleterious health effects in humans and wildlife associated with ingesting fish with elevated concentrations. A key to understanding elevated fish Hg concentrations is to examine methyl Hg dynamics at the base of food webs, including algae and zooplankton. Predicting determinants of methyl Hg concentrations in lower trophic level biota remains an active area of research. This study was conducted to assess Hg concentrations in biota of the Finger Lakes (New York, USA), a region where fisheries are an important economic driver, but where no comprehensive assessment of food web Hg dynamics has been completed to date. Sources of Hg in the region include atmospheric pollution from an active coal-fired power plant. The objectives of this study were to: 1) determine if fish Hg concentrations were of concern, 2) assess differences in Hg accumulation among lakes and determine predictors of fish Hg concentrations, and 3) evaluate the predictive power of monthly zooplankton methyl Hg concentrations on fish Hg concentrations. From May - October 2015, suspended particulate matter, zooplankton, and benthos were sampled monthly in five of the Finger Lakes (Honeoye, Canandaigua, Seneca, Cayuga, and Owasco Lakes). Fish were sampled once over the same study period and species were targeted from all trophic levels. Results for top predatory fish including Lake Trout (Salvelinus namaycush), Largemouth Bass (Micropterus salmoides), and Walleye (Sander vitreus) showed significant differences among lakes, and elevated concentrations are above US Environmental Protection Agency's screening value (300 ng/g wet weight). No clear pattern in Hg levels among lakes was evident in lower trophic level fishes such as Yellow Perch (Perca flavescens) and Golden Shiner (Notemigonus crysoleucas), but concentrations were low. Benthivorous Brown Bullhead (Ameiurus nebulosus) exhibited significant differences in Hg among lakes with

Contrasting past and current numbers of bears visiting Yellowstone cutthroat trout streams

Science.gov (United States)

Haroldson, Mark A.; Schwartz, Charles C.; Teisberg, Justin E.; Gunther, Kerry A.; Fortin, Jennifer K.; Robbins, Charles T.

2014-01-01

Spawning cutthroat trout (Oncorhynchus clarkii bouvieri) were historically abundant within tributary streams of Yellowstone Lake within Yellowstone National Park and were a highly digestible source of energy and protein for Yellowstone’s grizzly bears (Ursus arctos) and black bears (U. americanus). The cutthroat trout population has subsequently declined since the introduction of non-native lake trout (Salvelinus namaycush), and in response to effects of drought and whirling disease (Myxobolus cerebralis). The trout population, duration of spawning runs, and indices of bear use of spawning streams had declined in some regions of the lake by 1997–2000. We initiated a 3-year study in 2007 to assess whether numbers of spawning fish, black bears, and grizzly bears within and alongside stream corridors had changed since 1997– 2000. We estimated numbers of grizzly bears and black bears by first compiling encounter histories of individual bears visiting 48 hair-snag sites along 35 historically fished streams.We analyzed DNA encounter histories with Pradel-recruitment and Jolly-Seber (POPAN) capture-mark-recapture models. When compared to 1997–2000, the current number of spawning cutthroat trout per stream and the number of streams with cutthroat trout has decreased. We estimated that 48 (95% CI¼42–56) male and 23 (95% CI¼21–27) female grizzly bears visited the historically fished tributary streams during our study. In any 1- year, 46 to 59 independent grizzly bears (8–10% of estimated Greater Yellowstone Ecosystem population) visited these streams. When compared with estimates from the 1997 to 2000 study and adjusted for equal effort, the number of grizzly bears using the stream corridors decreased by 63%. Additionally, the number of black bears decreased between 64% and 84%. We also document an increased proportion of bears of both species visiting front-country (i.e., near human development) streams. With the recovery of cutthroat trout, we suggest bears

Fibrosis biomarkers in workers exposed to MWCNTs

International Nuclear Information System (INIS)

Fatkhutdinova, Liliya M.; Khaliullin, Timur O.; Vasil'yeva, Olga L.; Zalyalov, Ramil R.; Mustafin, Ilshat G.; Kisin, Elena R.; Birch, M. Eileen; Yanamala, Naveena; Shvedova, Anna A.

2016-01-01

Multi-walled carbon nanotubes (MWCNT) with their unique physico-chemical properties offer numerous technological advantages and are projected to drive the next generation of manufacturing growth. As MWCNT have already found utility in different industries including construction, engineering, energy production, space exploration and biomedicine, large quantities of MWCNT may reach the environment and inadvertently lead to human exposure. This necessitates the urgent assessment of their potential health effects in humans. The current study was carried out at NanotechCenter Ltd. Enterprise (Tambov, Russia) where large-scale manufacturing of MWCNT along with relatively high occupational exposure levels was reported. The goal of this small cross-sectional study was to evaluate potential biomarkers during occupational exposure to MWCNT. All air samples were collected at the workplaces from both specific areas and personal breathing zones using filter-based devices to quantitate elemental carbon and perform particle analysis by TEM. Biological fluids of nasal lavage, induced sputum and blood serum were obtained from MWCNT-exposed and non-exposed workers for assessment of inflammatory and fibrotic markers. It was found that exposure to MWCNTs caused significant increase in IL-1β, IL6, TNF-α, inflammatory cytokines and KL-6, a serological biomarker for interstitial lung disease in collected sputum samples. Moreover, the level of TGF-β1 was increased in serum obtained from young exposed workers. Overall, the results from this study revealed accumulation of inflammatory and fibrotic biomarkers in biofluids of workers manufacturing MWCNTs. Therefore, the biomarkers analyzed should be considered for the assessment of health effects of occupational exposure to MWCNT in cross-sectional epidemiological studies. - Highlights: • The effects of MWCNT exposure in humans remain unclear. • We found increased KL-6/TGF-β levels in the biofluids of MWCNT-exposed workers. �

Fibrosis biomarkers in workers exposed to MWCNTs

Energy Technology Data Exchange (ETDEWEB)

Fatkhutdinova, Liliya M., E-mail: liliya.fatkhutdinova@gmail.com [Kazan State Medical University, ul. Butlerova 49, Kazan 420012 (Russian Federation); Khaliullin, Timur O., E-mail: Khaliullin.40k@gmail.com [Kazan State Medical University, ul. Butlerova 49, Kazan 420012 (Russian Federation); Department of Physiology & Pharmacology, WVU, Morgantown, WV (United States); Vasil' yeva, Olga L., E-mail: volgaleon@gmail.com [Kazan State Medical University, ul. Butlerova 49, Kazan 420012 (Russian Federation); Zalyalov, Ramil R., E-mail: zalyalov.ramil@gmail.com [Kazan State Medical University, ul. Butlerova 49, Kazan 420012 (Russian Federation); Mustafin, Ilshat G., E-mail: ilshat64@mail.ru [Kazan State Medical University, ul. Butlerova 49, Kazan 420012 (Russian Federation); Kisin, Elena R., E-mail: edk8@cdc.gov [National Institute for Occupational Safety and Health, Morgantown, WV (United States); Birch, M. Eileen, E-mail: mib2@cdc.gov [National Institute for Occupational Safety and Health, Cincinnati, OH (United States); Yanamala, Naveena, E-mail: wqu1@cdc.gov [National Institute for Occupational Safety and Health, Morgantown, WV (United States); Shvedova, Anna A., E-mail: ats1@cdc.gov [National Institute for Occupational Safety and Health, Morgantown, WV (United States); Department of Physiology & Pharmacology, WVU, Morgantown, WV (United States)

2016-05-15

Multi-walled carbon nanotubes (MWCNT) with their unique physico-chemical properties offer numerous technological advantages and are projected to drive the next generation of manufacturing growth. As MWCNT have already found utility in different industries including construction, engineering, energy production, space exploration and biomedicine, large quantities of MWCNT may reach the environment and inadvertently lead to human exposure. This necessitates the urgent assessment of their potential health effects in humans. The current study was carried out at NanotechCenter Ltd. Enterprise (Tambov, Russia) where large-scale manufacturing of MWCNT along with relatively high occupational exposure levels was reported. The goal of this small cross-sectional study was to evaluate potential biomarkers during occupational exposure to MWCNT. All air samples were collected at the workplaces from both specific areas and personal breathing zones using filter-based devices to quantitate elemental carbon and perform particle analysis by TEM. Biological fluids of nasal lavage, induced sputum and blood serum were obtained from MWCNT-exposed and non-exposed workers for assessment of inflammatory and fibrotic markers. It was found that exposure to MWCNTs caused significant increase in IL-1β, IL6, TNF-α, inflammatory cytokines and KL-6, a serological biomarker for interstitial lung disease in collected sputum samples. Moreover, the level of TGF-β1 was increased in serum obtained from young exposed workers. Overall, the results from this study revealed accumulation of inflammatory and fibrotic biomarkers in biofluids of workers manufacturing MWCNTs. Therefore, the biomarkers analyzed should be considered for the assessment of health effects of occupational exposure to MWCNT in cross-sectional epidemiological studies. - Highlights: • The effects of MWCNT exposure in humans remain unclear. • We found increased KL-6/TGF-β levels in the biofluids of MWCNT-exposed workers. �

Children exposed to war/terrorism.

Science.gov (United States)

Shaw, Jon A

2003-12-01

This paper reviews the prevalence of psychological morbidities in children who have been exposed to war-related traumas or terrorism as well as the diversity of war-related casualties and their associated psychological responses. The psychological responses to war-related stressors are categorized as (1) little or no reaction, (2) acute emotional and behavioral effects, and (3) long-term effects. Specific categories of war-related casualties discussed include refugee status, traumatic bereavement, effects of parental absence, and child soldiers. Psychological responses associated with terrorism and bioterrorism are presented. Lastly, mediators of the psychological response to war-related stressors are discussed, to include exposure effects, gender effects, parental, family and social factors, and child-specific factors. Children exposed to war-related stressors experience a spectrum of psychological morbidities including posttraumatic stress symptomatology, mood disorders, externalizing and disruptive behaviors, and somatic symptoms determined by exposure dose effect. Specific questions for future research are identified.

Obstetric Outcomes of Mothers Previously Exposed to Sexual Violence.

Directory of Open Access Journals (Sweden)

Agnes Gisladottir

Full Text Available There is a scarcity of data on the association of sexual violence and women's subsequent obstetric outcomes. Our aim was to investigate whether women exposed to sexual violence as teenagers (12-19 years of age or adults present with different obstetric outcomes than women with no record of such violence.We linked detailed prospectively collected information on women attending a Rape Trauma Service (RTS to the Icelandic Medical Birth Registry (IBR. Women who attended the RTS in 1993-2010 and delivered (on average 5.8 years later at least one singleton infant in Iceland through 2012 formed our exposed cohort (n = 1068. For each exposed woman's delivery, nine deliveries by women with no RTS attendance were randomly selected from the IBR (n = 9126 matched on age, parity, and year and season of delivery. Information on smoking and Body mass index (BMI was available for a sub-sample (n = 792 exposed and n = 1416 non-exposed women. Poisson regression models were used to estimate Relative Risks (RR with 95% confidence intervals (CI.Compared with non-exposed women, exposed women presented with increased risks of maternal distress during labor and delivery (RR 1.68, 95% CI 1.01-2.79, prolonged first stage of labor (RR 1.40, 95% CI 1.03-1.88, antepartum bleeding (RR 1.95, 95% CI 1.22-3.07 and emergency instrumental delivery (RR 1.16, 95% CI 1.00-1.34. Slightly higher risks were seen for women assaulted as teenagers. Overall, we did not observe differences between the groups regarding the risk of elective cesarean section (RR 0.86, 95% CI 0.61-1.21, except for a reduced risk among those assaulted as teenagers (RR 0.56, 95% CI 0.34-0.93. Adjusting for maternal smoking and BMI in a sub-sample did not substantially affect point estimates.Our prospective data suggest that women with a history of sexual assault, particularly as teenagers, are at increased risks of some adverse obstetric outcomes.

Obstetric Outcomes of Mothers Previously Exposed to Sexual Violence.

Science.gov (United States)

Gisladottir, Agnes; Luque-Fernandez, Miguel Angel; Harlow, Bernard L; Gudmundsdottir, Berglind; Jonsdottir, Eyrun; Bjarnadottir, Ragnheidur I; Hauksdottir, Arna; Aspelund, Thor; Cnattingius, Sven; Valdimarsdottir, Unnur A

2016-01-01

There is a scarcity of data on the association of sexual violence and women's subsequent obstetric outcomes. Our aim was to investigate whether women exposed to sexual violence as teenagers (12-19 years of age) or adults present with different obstetric outcomes than women with no record of such violence. We linked detailed prospectively collected information on women attending a Rape Trauma Service (RTS) to the Icelandic Medical Birth Registry (IBR). Women who attended the RTS in 1993-2010 and delivered (on average 5.8 years later) at least one singleton infant in Iceland through 2012 formed our exposed cohort (n = 1068). For each exposed woman's delivery, nine deliveries by women with no RTS attendance were randomly selected from the IBR (n = 9126) matched on age, parity, and year and season of delivery. Information on smoking and Body mass index (BMI) was available for a sub-sample (n = 792 exposed and n = 1416 non-exposed women). Poisson regression models were used to estimate Relative Risks (RR) with 95% confidence intervals (CI). Compared with non-exposed women, exposed women presented with increased risks of maternal distress during labor and delivery (RR 1.68, 95% CI 1.01-2.79), prolonged first stage of labor (RR 1.40, 95% CI 1.03-1.88), antepartum bleeding (RR 1.95, 95% CI 1.22-3.07) and emergency instrumental delivery (RR 1.16, 95% CI 1.00-1.34). Slightly higher risks were seen for women assaulted as teenagers. Overall, we did not observe differences between the groups regarding the risk of elective cesarean section (RR 0.86, 95% CI 0.61-1.21), except for a reduced risk among those assaulted as teenagers (RR 0.56, 95% CI 0.34-0.93). Adjusting for maternal smoking and BMI in a sub-sample did not substantially affect point estimates. Our prospective data suggest that women with a history of sexual assault, particularly as teenagers, are at increased risks of some adverse obstetric outcomes.

PERSONAL FEATURES OF CHILDREN AND ADOLESCENTS ILL WITH RESPIRATORY TUBERCULOSIS EXPOSED AND NOT EXPOSED TO THE SOURCE OF INFECTION

Directory of Open Access Journals (Sweden)

N. V. Zolotova

2017-01-01

Full Text Available Specific personal features of 296 children and adolescents exposed to tuberculosis and those with unidentified exposure were comparatively analyzed. Children with unidentified exposure demonstrated psychic tension, poor self-control, poorly developed social communication skills which determined disruptive interpersonal relations and uneasy personal growth. Children exposed to tuberculosis in their families were characterized by judging didactive position towards their neighbors which was formed by dysfunctional patterns of relations in their parental families. Adolescent with unidentified exposure manifested the contrast combination of pre-morbid personal attitudes which had certain etiologic contribution to the development of borderline neurotic states. The higher level of destructive reactions in the interpersonal communication was observed in the adolescents exposed to tuberculosis in their families. Identified personal features are considered to be psychological factors determining the hyperactivation of adaptive systems at the pre-morbid state and consequent development of structural functional disorders in various systems of the host, as well as providing impact on the course of tuberculosis.

Functional morphology and biomechanics of the tongue-bite apparatus in salmonid and osteoglossomorph fishes

Science.gov (United States)

Camp, Ariel L; Konow, Nicolai; Sanford, Christopher P J

2009-01-01

The tongue-bite apparatus and its associated musculoskeletal elements of the pectoral girdle and neurocranium form the structural basis of raking, a unique prey-processing behaviour in salmonid and osteoglossomorph fishes. Using a quantitative approach, the functional osteology and myology of this system were compared between representatives of each lineage, i.e. the salmonid Salvelinus fontinalis (N =10) and the osteoglossomorph Chitala ornata(N = 8). Divergence was found in the morphology of the novel cleithrobranchial ligament, which potentially relates to kinematic differences between the raking lineage representatives. Salvelinus had greater anatomical cross-sectional areas of the epaxial, hypaxial and protractor hyoideus muscles, whereas Chitala had greater sternohyoideus and adductor mandibulae mass. Two osteology-based biomechanical models (a third-order lever for neurocranial elevation and a modified four-bar linkage for hyoid retraction) showed divergent force/velocity priorities in the study taxa. Salvelinus maximizes both force (via powerful cranial muscles) and velocity (through mechanical amplification) during raking. In contrast, Chitala has relatively low muscle force but more efficient force transmission through both mechanisms compared with Salvelinus. It remains unclear if and how behavioural modulation and specializations in the post-cranial anatomy may affect the force/velocity trade-offs in Chitala. Further studies of tongue-bite apparatus morphology and biomechanics in a broader species range may help to clarify the role that osteology and myology play in the evolution of behavioural diversity. PMID:19438765

Intrapulmonary reactions of workers exposed to dust and ozone

Energy Technology Data Exchange (ETDEWEB)

Tsunoda, T; Nakadate, T; Sakurai, M; Sakurai, Y

1984-01-01

Forty-one dust-and-ozone-exposed and 37 nonexposed workers, belonging to the Research and Development Division of a photo-copier manufacturing industry, were examined to assess the effect of the exposure to carbon, iron and resin dust and ozone in the air of the work environment by means of questionnaires on their physical condition, smoking habits and exposure history by interview, chest X-rays, testing of ventilatory functions, transcutaneous PO2 (tcPO2) test and H2O2-induced hemolysis test. The following results were obtained. Respirable dust concentrations in the air of the work place were 0.1-1.0 mg/m3, total dust concentrations 0.2-2.0 mg/m3, and ozone concentrations 0.004-0.06 ppm (0.008-0.12 mg/m3). According to the Japanese Classification of Radiographs of Pneumoconioses, the exposed workers showed a higher rate of profusion 0/1 and over, and category 1 and over (1/0 and over) than the nonexposed workers. Ventilatory function testing revealed no difference between exposed workers and nonexposed workers, but small airway narrowing was suspected in smoking workers in comparison with nonsmoking workers. Transcutaneous PO2 showed no difference between exposed and nonexposed workers, between smoking and nonsmoking workers, and between any of the paired six combinations out of the four groups of workers, i.e., nonsmoking and nonexposed, nonsmoking and exposed, smoking and nonexposed, and smoking and exposed. It was estimated by H2O2-induced hemolysis test that smoking and/or dust exposure, especially long-term exposure, gave rise to aggravation of fragility of the erythrocyte membrane by lipid peroxidation with ozone or active oxygen produced by the reaction of dust and alveolar macrophages.

Exposing diversity

DEFF Research Database (Denmark)

Nørtoft, Kamilla; Nordentoft, Helle Merete

professionals´ meetings with patients and relatives. In the paper we draw data from focus group discussions with interdisciplinary groups of health care professionals working in the area of care for older people. The video narratives used to initiate discussions are developed through ethnographic fieldwork...... in the homes of older people and in pedagogical institutions targeting older people. In the paper we look at the potentials and challenges in working with ethnographic video narratives as a pedagogical tool. Our findings indicate that the use of video narratives has the potential to expose the diversity...... focus on their own professional discipline and its tasks 2) stimulates collaborative learning when they discuss their different interpretations of the ethnographic video narratives and achieve a deeper understanding of each other’s work and their clients’ lifeworlds, which might lead to a better...

EXPOSE-E: an ESA astrobiology mission 1.5 years in space.

Science.gov (United States)

Rabbow, Elke; Rettberg, Petra; Barczyk, Simon; Bohmeier, Maria; Parpart, André; Panitz, Corinna; Horneck, Gerda; von Heise-Rotenburg, Ralf; Hoppenbrouwers, Tom; Willnecker, Rainer; Baglioni, Pietro; Demets, René; Dettmann, Jan; Reitz, Guenther

2012-05-01

The multi-user facility EXPOSE-E was designed by the European Space Agency to enable astrobiology research in space (low-Earth orbit). On 7 February 2008, EXPOSE-E was carried to the International Space Station (ISS) on the European Technology Exposure Facility (EuTEF) platform in the cargo bay of Space Shuttle STS-122 Atlantis. The facility was installed at the starboard cone of the Columbus module by extravehicular activity, where it remained in space for 1.5 years. EXPOSE-E was returned to Earth with STS-128 Discovery on 12 September 2009 for subsequent sample analysis. EXPOSE-E provided accommodation in three exposure trays for a variety of astrobiological test samples that were exposed to selected space conditions: either to space vacuum, solar electromagnetic radiation at >110 nm and cosmic radiation (trays 1 and 3) or to simulated martian surface conditions (tray 2). Data on UV radiation, cosmic radiation, and temperature were measured every 10 s and downlinked by telemetry. A parallel mission ground reference (MGR) experiment was performed on ground with a parallel set of hardware and samples under simulated space conditions. EXPOSE-E performed a successful 1.5-year mission in space.

Work ability score of solvent-exposed workers.

Science.gov (United States)

Furu, Heidi; Sainio, Markku; Hyvärinen, Hanna-Kaisa; Kaukiainen, Ari

2018-03-28

Occupational chronic solvent encephalopathy (CSE), characterized by neurocognitive dysfunction, often leads to early retirement. However, only the more severe cases are diagnosed with CSE, and little is known about the work ability of solvent-exposed workers in general. The aim was to study memory and concentration symptoms, work ability and the effect of both solvent-related and non-occupational factors on work ability, in an actively working solvent-exposed population. A questionnaire on exposure and health was sent to 3640 workers in four solvent-exposed fields, i.e. painters and floor-layers, boat builders, printers, and metal workers. The total number of responses was 1730. We determined the work ability score (WAS), a single question item of the Work Ability Index, and studied solvent exposure, demographic factors, Euroquest memory and concentration symptoms, chronic diseases, and employment status using univariate and multivariate analyses. The findings were compared to those of a corresponding national blue-collar reference population (n = 221), and a small cohort of workers with CSE (n = 18). The proportion of workers with memory and concentration symptoms was significantly associated with solvent exposure. The WAS of solvent-exposed workers was lower than that of the national blue-collar reference group, and the difference was significant in the oldest age group (those aged over 60). Solvent-exposed worker's WAS were higher than those of workers diagnosed with CSE. The WAS were lowest among painters and floor-layers, followed by metal workers and printers, and highest among boat builders. The strongest explanatory factors for poor work ability were the number of chronic diseases, age and employment status. Solvent exposure was a weak independent risk factor for reduced WAS, comparable to a level of high alcohol consumption. Even if memory and concentration symptoms were associated with higher solvent exposure, the effect of solvents on self

Biological behaviour of buccal cells exposed to blue light

International Nuclear Information System (INIS)

Gritsch, Kerstin; Ponsonnet, Laurence; Schembri, Catherine; Farge, Pierre; Pourreyron, Laurence; Grosgogeat, Brigitte

2008-01-01

Blue light is used in dental practise to cure resin-based materials, but the path of the light often includes oral tissues such as gingival tissues. While adverse effects of blue light exposure on cells - such as retina cells - are well known, few studies have investigated the impact of blue light exposure on oral cells. The aim of the present in vitro study was to assess the biological effects of blue light emitted by two dental curing devices (a plasma-arc and a light-emitting diode curing unit) on human gingival fibroblasts. Light intensities and light-induced temperature rise were respectively measured with a radiometer and a thermocouple. Cellular response to blue light exposure was assessed by the observation of cell morphology (scanning electron microscopy) and the estimation of cell mitochondrial activity (MTT assay). Light intensities measured at the clinical distance were 488 ± 42 mW/cm 2 for the plasma-arc unit and ranged from 61 ± 5 to 140 ± 16 mW/cm 2 for the light-emitting diodes unit, according to the curing program used. The highest temperature rise was 0.5 and 3.5 deg. C for exposure to the plasma-arc light and to the light-emitting diodes light, respectively. Results showed no differences between exposed- and non-exposed cells in regards to cell morphology. However, cells exposed to blue light presented an increased mitochondrial activity compared to control cells (non-exposed), and mostly those exposed to plasma-arc light

Histomorphological patterns in osseous rests exposed at fire

International Nuclear Information System (INIS)

Medina, C.; Tiesler, V.; Oliva, A.I.; Quintana, P.

2005-01-01

Histomorphology as part of morphological research studies bony structure on the tissue level. Its methods are applied in this investigation to evaluate histomorphological impact patterns in heat-exposed bony material, particularly color changes, fissure patterns, volumetric reduction, and changes in the size of Haversian canals. These variables were evaluated in exposed thin sections of porcine long bones, obtained during two experimental series. The first one was conducted under stable thermal conditions in a furnace by measuring heat impact in stepped time (I to S hours) and temperature intervals (200 to 800 C). During a second experimental phase, bony samples were exposed to direct fire in defined time and heat intervals. The treated specimens were then sectioned and microscopically scrutinized. The results presented here were designed to offer new analytical, measurable standards in the investigation of forms of heat exposition of the human body, applicable in forensics and the study of ancient Maya posthumous body treatments. (Author)

Differentiation of peripheral lymphocyte population in Pu-exposed beagle dogs

International Nuclear Information System (INIS)

Morris, J.E.

1977-01-01

The percentage of peripheral lymphocytes binding fluorescent-labeled anticanine antibodies was measured in plutonium-oxide-exposed and unexposed beagle dogs. With this assay system, there was a significant decrease in the percentage of lymphocytes binding the labeled antibody in exposed animals compared to control animals

Evaluation of Dynamic Disulphide/Thiol Homeostasis in Silica Exposed Workers

Directory of Open Access Journals (Sweden)

Meşide Gündüzöz

2017-04-01

Full Text Available Background: Oxidative stress is implicated as one of the main molecular mechanism underlying silicosis. Aims: In this study, our aim was to asses the redox status in occupationally silica-exposed workers, by evaluating the dynamic thiol-disulphide homeostasis. Study Design: Case-control study. Methods: Thirty-six male workers occupationally exposed to silica particles and 30 healthy volunteers, working as office workers were included to the study. Posteroanterior chest radiographs and pulmonary function tests of both groups were evaluated. Also serum thiol disulphide levels were measured using the spectrophotometric method described by Erel and Neşelioğlu. Results: Among the 36 workers that underwent pulmonary function tests 6 (17% had obstructive, 7 (19% had restrictive, 6 (17% had obstructive and restrictive signs whereas 17 (47% had no signs. The mean PFTs results of silica-exposed workers were significantly lower than control subjects. The serum disulphide levels of silica-exposed workers were significantly higher than control subjects (23.84±5.89 μmol/L and 21.18±3.44 μmol/L, respectively p=0.02. Conclusion: The serum disulphide levels, a biomarker of oxidative stress, are found to be higher in silica-exposed workers

Analysis of reproductive function in persons exposed to chronic radiation

Energy Technology Data Exchange (ETDEWEB)

Kossenko, M.M.; Ostroumova, E.V.; Vyushkova, O.V. [Urals Research Center for Radiation Medicine, Chelyabinsk (Russian Federation)

2000-05-01

The purpose of the study was to analyze the reproductive function in individuals exposed to radiation in the riverside villages on the Techa in the Southern Urals. The exposure of the population, numbering 28000, occurred in 1950-1956 as a result of discharges into the river of radioactive wastes from the Mayak facility for processing weapon plutonium. The residents were exposed to chronic radiation, both external and internal. The range of exposure doses to gonads was sufficiently wide: 20-1270 mSv. However, the distribution of doses among the exposed individuals was ununiform, and the proportion of people whose dose was below 120 mGy accounted for 74%. The following characteristics of exposed women were analyzed: menstrual function, outcomes of pregnancy, birth rates, health status for newborns. The analysis of the menstrual function in exposed women showed that in persons exposed in childhood, menarche was registered at the age of 14.3 years, on the average (based on literature sources, menarche is attained at the age of 13 for unexposed population). The mean age at menopause was 47.9 years for exposed women (the respective mean value for Russia is 50.8 years). Pregnancy outcomes were analyzed in 9000 exposed women. The rate of medical and criminal abortions was estimated as 79 per 100 labors. The rate of spontaneous abortions for exposed women was slightly higher, 3.11%, than for controls, 2.30%; these difference, however, were statistically insignificant. The total loss of fetus or neonate (unfavorable outcomes of pregnancy: spontaneous abortions, stillbirths, early neonatal death) was estimated to be 4.58% at zero dose. Exposure to gonads at the dose 1 Sv, estimated using the above-indicated method, yielded 3% of additional unfavorable outcomes of pregnancy. It was shown, based on the analysis of birth rates for the Techa Cohort that they had not undergone any essential changes over the first 25 years of exposure compared to the respective coefficients for

Analysis of reproductive function in persons exposed to chronic radiation

International Nuclear Information System (INIS)

Kossenko, M.M.; Ostroumova, E.V.; Vyushkova, O.V.

2000-01-01

The purpose of the study was to analyze the reproductive function in individuals exposed to radiation in the riverside villages on the Techa in the Southern Urals. The exposure of the population, numbering 28000, occurred in 1950-1956 as a result of discharges into the river of radioactive wastes from the Mayak facility for processing weapon plutonium. The residents were exposed to chronic radiation, both external and internal. The range of exposure doses to gonads was sufficiently wide: 20-1270 mSv. However, the distribution of doses among the exposed individuals was ununiform, and the proportion of people whose dose was below 120 mGy accounted for 74%. The following characteristics of exposed women were analyzed: menstrual function, outcomes of pregnancy, birth rates, health status for newborns. The analysis of the menstrual function in exposed women showed that in persons exposed in childhood, menarche was registered at the age of 14.3 years, on the average (based on literature sources, menarche is attained at the age of 13 for unexposed population). The mean age at menopause was 47.9 years for exposed women (the respective mean value for Russia is 50.8 years). Pregnancy outcomes were analyzed in 9000 exposed women. The rate of medical and criminal abortions was estimated as 79 per 100 labors. The rate of spontaneous abortions for exposed women was slightly higher, 3.11%, than for controls, 2.30%; these difference, however, were statistically insignificant. The total loss of fetus or neonate (unfavorable outcomes of pregnancy: spontaneous abortions, stillbirths, early neonatal death) was estimated to be 4.58% at zero dose. Exposure to gonads at the dose 1 Sv, estimated using the above-indicated method, yielded 3% of additional unfavorable outcomes of pregnancy. It was shown, based on the analysis of birth rates for the Techa Cohort that they had not undergone any essential changes over the first 25 years of exposure compared to the respective coefficients for

Cancer risk in men exposed in utero to diethylstilbestrol.

Science.gov (United States)

Strohsnitter, W C; Noller, K L; Hoover, R N; Robboy, S J; Palmer, J R; Titus-Ernstoff, L; Kaufman, R H; Adam, E; Herbst, A L; Hatch, E E

2001-04-04

An association between prenatal diethylstilbestrol (DES) exposure and cancer in men, especially testicular cancer, has been suspected, but findings from case-control studies have been inconsistent. This study was conducted to investigate the association between prenatal DES exposure and cancer risk in men via prospective follow-up. A total of 3613 men whose prenatal DES exposure status was known were followed from 1978 through 1994. The overall and site-specific cancer incidence rates among the DES-exposed men were compared with those of the unexposed men in the study and with population-based rates. The relative rate (RR) was used to assess the strength of the association between prenatal DES exposure and cancer development. All statistical tests were two-sided. Overall cancer rates among DES-exposed men were similar to those among unexposed men (RR = 1.07; 95% confidence interval [CI] = 0.58 to 1.96) and to national rates (RR = 0.99; 95% CI = 0.65 to 1.44). Testicular cancer may be elevated among DES-exposed men, since the RRs for testicular cancer were 3.05 (95% CI = 0.65 to 22.0) times those of unexposed men in the study and 2.04 (95% CI = 0.82 to 4.20) times those of males in the population-based rates. The higher rate of testicular cancer in the DES-exposed men is, however, also compatible with a chance observation. To date, men exposed to DES in utero do not appear to have an increased risk of most cancers. It remains uncertain, however, whether prenatal DES exposure is associated with testicular cancer.

Cytogenetic Follow-up Study of Population Occupationally Exposed to Nonionizing Radiation

International Nuclear Information System (INIS)

Garaj-Vrhovac, V.; Kasuba, V.; Vojvodic, S.

1998-01-01

The aim of this investigation was to analyse the results of a four year follow- up study of chromosome aberrations in a population occupationally exposed to microwave radiation. The study included a group of 30 healthy volunteers - radar technicians occupationally exposed to microwave radiation and a group of 30 healthy controls from the general population. The average duration of employment of the exposed subjects was 16 years. The chromosome aberrations assay was carried out on 48 h culture of lymphocytes. Microwave power density was measured with Raham model 4A (General Microwave Corporation, Farmingdale, NY) at different workplaces. The measurements of electromagnetic field power density distribution at different workplaces show that during an ordinary workday the examinees stay in zones with power density below 5 mW/cm 2 with a frequency range of 1250-1350 MHz. The chromosomal type of aberrations in the exposed group during the 4-year follow up study was predominantly higher than in the control group. The total percentage of chromosome aberrations for the exposed group in the first year of the study was 2.36%, in the second 1.43%, in the third 2.88%, and in the fourth year 2.60%, while for the control group was 1.39%. In every year of investigation in exposed group manifested dicentric chromosomes, while in last two years ring chromosome also detected. Mutagenic changes in the somatic cells detected in exposed subjects pointed to the fact that these cellular damages can be related to continuous occupational exposure to microwave radiation. (author)

Alteration of the retinoblastoma gene locus in radium-exposed individuals

International Nuclear Information System (INIS)

Hardwick, J.P.; Schlenker, R.; Huberman, E.

1991-01-01

This study was performed to determine if the retinoblastoma suppressor gene was altered in individuals exposed to radium. We analyzed the Rb gene in 30 individuals, 17 of whom were exposed to radium either occupationally or iatrogenically. In the kidney DNA from four of nine radium-exposed individuals, the Rb gene was deleted. Three of these alterations in the Rb gene were internal deletions, which resulted in the absence of Rb mRNA accumulation. These results imply that the Rb gene is susceptible to radium-induced damage and confirm previous showing that radiation preferentially causes genomic deletions. The pronounced alterations in the non-tumorigenic femurs from radium-exposed individuals suggests that in the many years of exposure there was a selection of cells with alterations, presumably because of their growth advantage. Also it implies that deletions of one of the Rb alleles can be one of the events (perhaps an initial one) in the progression of radium-induced sarcomas. 11 refs., 2 figs

Attention bias in earthquake-exposed survivors: an event-related potential study.

Science.gov (United States)

Zhang, Yan; Kong, Fanchang; Han, Li; Najam Ul Hasan, Abbasi; Chen, Hong

2014-12-01

The Chinese Wenchuan earthquake, which happened on the 28th of May in 2008, may leave deep invisible scars in individuals. China has a large number of children and adolescents, who tend to be most vulnerable because they are in an early stage of human development and possible post-traumatic psychological distress may have a life-long consequence. Trauma survivors without post-traumatic stress disorder (PTSD) have received little attention in previous studies, especially in event-related potential (ERP) studies. We compared the attention bias to threat stimuli between the earthquake-exposed group and the control group in a masked version of the dot probe task. The target probe presented at the same space location consistent with earthquake-related words was the congruent trial, while in the space location of neutral words was the incongruent trial. Thirteen earthquake-exposed middle school students without PTSD and 13 matched controls were included in this investigation. The earthquake-exposed group showed significantly faster RTs to congruent trials than to incongruent trials. The earthquake-exposed group produced significantly shorter C1 and P1 latencies and larger C1, P1 and P2 amplitudes than the control group. In particular, enhanced P1 amplitude to threat stimuli was observed in the earthquake-exposed group. These findings are in agreement with the prediction that earthquake-exposed survivors have an attention bias to threat stimuli. The traumatic event had a much greater effect on earthquake-exposed survivors even if they showed no PTSD symptoms than individuals in the controls. These results will provide neurobiological evidences for effective intervention and prevention to post-traumatic mental problems. Copyright © 2014 Elsevier B.V. All rights reserved.

Increased gluconeogenesis in rats exposed to hyper-G stress

International Nuclear Information System (INIS)

Daligcon, B.C.; Oyama, J.; Hannak, K.

1985-01-01

The role of gluconeogenesis on the increase in plasma glucose and liver glycogen of rats exposed to hyper-G (radial acceleration) stress was determined. Overnight-fasted, male Sprague-Dawley rats (250-300 g) were injected i.p. with uniformly labeled 14 C lactate, alanine, or glycerol (5 μCi/rat) and immediately exposed to 3.1 G for 0.25, 0.50, and 1.0 hr. 14 C incorporation of the labeled substrates into plasma glucose and liver glycogen was measured and compared to noncentrifuged control rats injected in a similar manner. Significant increases in 14 C incorporation of all three labeled substrates into plasma glucose were observed in centrifuged rats at all exposure periods; 14 C incorporation into liver glycogen was significantly increased only at 0.50 and 1.0 hr. The i.p. administration (5 mg/100-g body wt) of 5-methoxyindole-2-carboxylic acid, a potent gluconeogenesis inhibitor, prior to centrifugation blocked the increase in plasma glucose and liver glycogen during the first hour of centrifugation. The increase in plasma glucose and liver glycogen was also abolished in adrenodemedullated rats exposed to centrifugation for 1.0 hr. Propranolol, a beta-adrenergic blocker, suppressed the increase in plasma glucose of rats exposed to centrifugation for 0.25 hr. From the results of this study, it is concluded that the initial, rapid rise in plasma glucose as well as the increase in liver glycogen of rats exposed to hyper-G stress can be attributed to an increased rate of gluconeogenesis, and that epinephrine plays a dominant role during the early stages of exposure to centrifugation. 11 references, 3 tables

Technical Nuances of Exposing Rat Common Carotid Arteries for Practicing Microsurgical Anastomosis.

Science.gov (United States)

Tayebi Meybodi, Ali; Aklinski, Joseph; Gandhi, Sirin; Lawton, Michael T; Preul, Mark C

2018-04-17

Animal models are commonly used in training protocols for microsurgical vascular anastomosis. Rat common carotid arteries (CCAs) are frequently used for this purpose. Much attention has been paid to the technical details of various anastomosis configurations using these arteries. However, technical nuances of exposing rat CCAs have been understudied. The purpose of this study is to describe nuances of technique for safely and efficiently exposing rat CCAs in preparation for a vascular anastomosis. Bilateral CCAs were exposed and prepared for anastomosis in 10 anesthetized Sprague-Dawley rats through a midline cervical incision. The exposed length of the CCA was measured. Additionally, technical nuances of exposure and surgically relevant anatomic details were recorded. The CCAs were exposed from the sternoclavicular joint to their bifurcation (average length, 19.1 ± 2.8 mm). Tenets important for a safe and efficient exposure of the CCAs included 1) generous subcutaneous dissection to expose the external jugular veins (EJVs), 2) avoiding injury to or compression of the EJVs, 3) superior mobilization of the salivary glands, 4) division of internal jugular veins, 5) opening the carotid sheath at its midlevel and from medial to lateral, and 6) avoiding injury to the vagus nerve or sympathetic trunk. Using the principles introduced in this study, trainees may safely and efficiently expose rat CCAs in preparation for a bypass. Copyright © 2018 Elsevier Inc. All rights reserved.

DNA damage and cytotoxicity in pathology laboratory technicians exposed to organic solvents

Directory of Open Access Journals (Sweden)

TATIANE DE AQUINO

2016-03-01

Full Text Available The aim of this study was to evaluate potential DNA damage and cytotoxicity in pathology laboratory technicians exposed to organic solvents, mainly xylene. Peripheral blood and buccal cells samples were collected from 18 technicians occupationally exposed to organic solvents and 11 non-exposed individuals. The technicians were sampled at two moments: Monday and Friday. DNA damage and cytotoxicity were evaluated using the Comet Assay and the Buccal Micronucleus Cytome assay. Fifteen subjects (83.5% of the exposed group to solvents complained about some symptom probably related to contact with vapours of organic solvents. DNA damage in the exposed group to solvents was nearly 2-fold higher on Friday than on Monday, and in both moments the individuals of this group showed higher levels of DNA damage in relation to controls. No statistical difference was detected in buccal cell micronucleus frequency between the laboratory technicians and the control group. However, in the analysis performed on Friday, technicians presented higher frequency (about 3-fold of karyolytic and apoptotic-like cells (karyorrhectic and pyknotic in relation to control group. Considering the damage frequency and the working time, a positive correlation was found in the exposed group to solvents (r=0.468; p=0.05. The results suggest that pathology laboratory workers inappropriately exposed to organic solvents have increased levels of DNA damage.

Unusual presentation of necrotizing fasciitis in an HIV exposed infant

African Journals Online (AJOL)

... presentation of NF, in this instance, it presented on the scalp, in an HIV exposed neonate. It also stressed the importance prompt diagnosis of all skin lesions in HIV exposed neonates, and the role of early diagnosis and aggressive multi disciplinary team management in salvaging NF which is a potentially fatal condition.

Epidemiological studies of some populations exposed to ionizing radiation

International Nuclear Information System (INIS)

Weeks, J.L.

1985-08-01

During 1984 September 19 and 20, a meeting was held at the Whiteshell Nuclear Research Establishment, Pinawa, Manitoba to discuss current epidemiological studies of populations exposed to low levels of ionizing radiation. Twelve representatives from three countries attended the meeting and eleven papers were extensively discussed. The majority of these papers described studies of populations occupationally exposed to radiation. The report contains summaries of the papers presented and of the discussions that took place

Ice nucleation of ammonia gas exposed montmorillonite mineral dust particles

Directory of Open Access Journals (Sweden)

A. Salam

2007-07-01

Full Text Available The ice nucleation characteristics of montmorillonite mineral dust aerosols with and without exposure to ammonia gas were measured at different atmospheric temperatures and relative humidities with a continuous flow diffusion chamber. The montmorillonite particles were exposed to pure (100% and diluted ammonia gas (25 ppm at room temperature in a stainless steel chamber. There was no significant change in the mineral dust particle size distribution due to the ammonia gas exposure. 100% pure ammonia gas exposure enhanced the ice nucleating fraction of montmorillonite mineral dust particles 3 to 8 times at 90% relative humidity with respect to water (RHw and 5 to 8 times at 100% RHw for 120 min exposure time compared to unexposed montmorillonite within our experimental conditions. The percentages of active ice nuclei were 2 to 8 times higher at 90% RHw and 2 to 7 times higher at 100% RHw in 25 ppm ammonia exposed montmorillonite compared to unexposed montmorillonite. All montmorillonite particles are more efficient as ice nuclei with increasing relative humidities and decreasing temperatures. The activation temperature of montmorillonite exposed to 100% pure ammonia was 15°C higher than for unexposed montmorillonite particles at 90% RHw. In the 25 ppm ammonia exposed montmorillonite experiments, the activation temperature was 10°C warmer than unexposed montmorillonite at 90% RHw. Degassing does not reverse the ice nucleating ability of ammonia exposed montmorillonite mineral dust particles suggesting that the ammonia is chemically bound to the montmorillonite particle. This is the first experimental evidence that ammonia gas exposed montmorillonite mineral dust particles can enhance its activation as ice nuclei and that the activation can occur at temperatures warmer than –10°C where natural atmospheric ice nuclei are very scarce.

Maternal ability to take care of children exposed to HIV

Directory of Open Access Journals (Sweden)

Julyana Gomes Freitas

2013-07-01

Full Text Available OBJECTIVE: to assess the ability of mothers to take care of children exposed to HIV, using the Assessment Scale of Care Skills for Children Exposed to HIV at Birth and to check the association between the scale dimensions and maternal characteristics. METHOD: this cross-sectional study involved 62 HIV+ mothers whose children of up to one year old had been exposed to the virus at birth. The Assessment Scale of Care Skills for Children Exposed to HIV at Birth consists of 52 items and five dimensions, indicating high, moderate or low care ability. RESULTS: 72.7% of the mothers appropriately offered zidovudine syrup; 86.0% were highly skilled to prepare and administer milk formula; 44.4% were moderately able to prepare and administer complementary feeding; 76.5% revealed high ability to administer prophylactic treatment against pneumonia and 95.3% demonstrated high abilities for clinical monitoring and immunization. Significant associations were found between some maternal variables and the scale dimensions. CONCLUSION: the scale permits the assessment of maternal care delivery to these children and the accomplishment of specific child health interventions.

A synthetic medical and sociological study of A-bomb exposed twin, 7

International Nuclear Information System (INIS)

Watanabe, Shoji; Satow, Yukio; Kyo, Taiichi

1984-01-01

The status of A-bomb exposure and family or relative relationship were investigated in seven twin pairs exposed to A-bomb (14 survivors). The survivors ranged in age between 4 and 24 years when they were exposed to A-bomb. Twins' relationship was comparatively strong. Both of the twins who were exposed to A-bomb tended to be closely connected with each other because of the fearful experience of A-bomb exposure and the subsequent hard social life. Even though one of the pair was not exposed to A-bomb, he (she) was likely to continue to help the other for a long time to restore from the disaster. (Namekawa, K.)

Effects of Circadian Disruption on Methamphetamine Consumption in Methamphetamine-Exposed Rats

Science.gov (United States)

Doyle, Susan E.; Feng, Hanting; Garber, Garrett; Menaker, Michael; Lynch, Wendy J.

2015-01-01

Rationale A substantial number of clinical studies indicate associations between sleep abnormalities and drug abuse; however, the role played by the circadian system in the development of addiction is largely unknown. Objective The aim of this study was to examine the effects of experimentally induced chronic jet lag on methamphetamine consumption in a rat model of methamphetamine drinking. Methods Male Sprague-Dawley rats (n=32) were housed in running wheel cages in a 12:12 light:dark cycle. One group of rats (n=16) was given two weeks of forced methamphetamine consumption (0.01% in drinking water; meth pre-exposed) while a second group (n=16, not pre-exposed) received water only. This was followed by a two week abstinence period during which half of the animals from each group were exposed to 4 consecutive 6-hr advancing phase shifts of the light:dark cycle, while the other half remained on the original light:dark cycle. Methamphetamine consumption was assessed in all rats following the deprivation period using a two-bottle choice paradigm. Results Methamphetamine consumption was initially lower in methamphetamine pre-exposed vs. not pre-exposed rats. However, during the second week following abstinence, consumption was significantly higher in phase shifted rats of the methamphetamine pre-exposed group compared to all other groups. Conclusions These data reveal an effect of circadian rhythm disturbance on methamphetamine consumption, and suggest that dysregulation of the circadian system be considered in the etiology of relapse and addiction. PMID:25543849

MODULACIÓN DE LA SINTESIS DE METALOTIONINAS EN Perna viridis PREEXPUESTOS A COBRE Y EXPUESTOS A CADMIO | MODULATION OF METALLOTHIONEIN SYNTHESIS IN Perna viridis PRE EXPOSED TO COPPER AND EXPOSED TO CADMIUM

Directory of Open Access Journals (Sweden)

Marín Lemus,

2014-02-01

Full Text Available The metallothioneins (Mts have been used as biomarkers because toxic metals such as Hg, Cd, Cu can induce their synthesis; however, environmental factors and the presence of other xenobiotics can determine the magnitude of the response in future exposures to metal ions. Metallothionein concentration was determinate in the soft tissue of Perna viridis juveniles pre-exposed to Cu and exposed to Cd (Cu/Cd for 21 days. For this, three experimental groups were established: exposed to Cd, pre-exposed to Cu and exposed to Cd and the control group (no metal. Cadmium accumulation in tissues of P. viridis was significantly higher in pre-exposed organisms to Cu, with an average value of 6.6 ± 1.9 mg/g, while in those exposed to Cd, was 4.7 ± 2.4 mg/g. Mts concentrations were also higher in the Cu/Cd experimental group, with a value of 1.36 ± 0.52 mg/g in relation to those exposed to Cd which had a value of 0.79 ± 0.47 mg/g. The relationship between Mts and bioaccumulation of Cd was significant in the group exposed to Cd, but not in the exposed Cu/Cd. These results suggest that Cu possibly acted as an inducer of Mts in the body, which led to increased accumulation of Cd in P. viridis and increase in Mts concentration. Tolerance and bioaccumulation of Cd in P. viridis was determined by previous exposure of the organism and hence its response on levels of MTs also depends on it.

Analysis of emotionality and locomotion in radio-frequency electromagnetic radiation exposed rats.

Science.gov (United States)

Narayanan, Sareesh Naduvil; Kumar, Raju Suresh; Paval, Jaijesh; Kedage, Vivekananda; Bhat, M Shankaranarayana; Nayak, Satheesha; Bhat, P Gopalakrishna

2013-07-01

In the current study the modulatory role of mobile phone radio-frequency electromagnetic radiation (RF-EMR) on emotionality and locomotion was evaluated in adolescent rats. Male albino Wistar rats (6-8 weeks old) were randomly assigned into the following groups having 12 animals in each group. Group I (Control): they remained in the home cage throughout the experimental period. Group II (Sham exposed): they were exposed to mobile phone in switch-off mode for 28 days, and Group III (RF-EMR exposed): they were exposed to RF-EMR (900 MHz) from an active GSM (Global system for mobile communications) mobile phone with a peak power density of 146.60 μW/cm(2) for 28 days. On 29th day, the animals were tested for emotionality and locomotion. Elevated plus maze (EPM) test revealed that, percentage of entries into the open arm, percentage of time spent on the open arm and distance travelled on the open arm were significantly reduced in the RF-EMR exposed rats. Rearing frequency and grooming frequency were also decreased in the RF-EMR exposed rats. Defecation boli count during the EPM test was more with the RF-EMR group. No statistically significant difference was found in total distance travelled, total arm entries, percentage of closed arm entries and parallelism index in the RF-EMR exposed rats compared to controls. Results indicate that mobile phone radiation could affect the emotionality of rats without affecting the general locomotion.

Screening and surveillance of workers exposed to mineral dusts

Energy Technology Data Exchange (ETDEWEB)

Wagner, G.R.

1997-12-31

This publication resulted from a World Health Organisation initiated project to investigate the harmonisation of definitions, approaches and methodologies for the screening and surveillance of workers exposed to mineral dust. The first part of the book provides definitions of screening and surveillance and describes the main elements of such programmes. The second part discusses the practical aspect of the screening and surveillance of working populations exposed to crystalline silica, coal mine dust and asbestos. Although no single set of guidelines is applicable to the development and implementation of a programme for the screening and surveillance of workers exposed to mineral dust, the recommendations, together with certain caveats, should provide a useful starting point. Annexes provide examples of existing programmes in various countries and environments and discuss the use and interpretation of questionnaires, lung spirometry and chest radiography. Overall the book should be of interest to occupational health professionals.

Liver function in workers exposed of the cosmetics industry.

Science.gov (United States)

Casale, T; Caciari, T; Rosati, M V; Biagi, M; De Sio, S; Andreozzi, G; Schifano, M P; Capozzella, A; Pimpinella, B; Tomei, G; Tomei, F

2013-01-01

The purpose of this study is to assess whether occupational exposure to substances used in the cosmetic factories may cause effects on the liver and blood counts in exposed workers. The study included 48 exposed workers and 86 unexposed controls. All workers included in the study underwent blood count, white blood count, total, direct and indirect bilirubin, transaminases, alkaline phosphatase and cholinesterase. The differences between the means and frequencies were compared using the Student's t-test and chi-square test with Yates correction and were considered significant when the p value was cosmetics industry had liver test values above the range. We noted a statistically significant higher prevalence of GPT (p cosmetics industry compared with the control group. The results obtained suggest that occupational exposure to low doses of substances used in the cosmetic industry is able to influence some liver parameters in occupationally exposed workers.

Are students exposed to tobacco smoke in German schools?

Directory of Open Access Journals (Sweden)

Heinrich, Joachim

2005-12-01

Full Text Available The aim of this study was to investigate to which extent 6th grade school children are exposed to tobacco smoke by others. As biomarker for the exposure to tobacco smoke nicotine and cotinine were measured in the urine. Our study population consisted of 771 schoolchildren aged 11-14 years who according to a questionnaire did not smoke. In addition we analysed the data of 459 school children who were not exposed to tobacco smoke at home. The nicotine and cotinine concentrations in the spontaneous urine sample were determined by HPLC methods.On average in about 20% of all non-smoking children, who were not exposed to tobacco smoke at home, biomarker (nicotine or cotinine were detected in the urine. The percentage of the detected biomarker values (nicotine and/or cotinine in the urine of the school children varied between 0% and 50% between schools. In addition we determined the proportion of smoking classmates per school. No positive association was found between the detected biomarker values of the non-smoking school children not exposed to tobacco smoke at home and the proportion of smokers per school. The concentration of biomarker depending on the time of day the urine samples were collected showed higher nicotine and cotinine values when the urine sample was collected between 10 and 12 o'clock in the morning compared to urine samples collected between 7 and 10 a.m.In spite of the limitations our study provides some evidence that children are exposed involuntarily to tobacco smoke by others at school. That is why our results support the requirement of a general legal ban on smoking for teachers, the school staff and students.

Analysis of the mortality of the progeny of exposed parents

International Nuclear Information System (INIS)

Kosenko, M.M.

1996-01-01

The purpose of this study was to analyze the values, time course, and structure of mortality of the progeny of exposed residents of villages on the banks of the Techa river in the Urals. The exposure was caused by discharge of radioactive waste of Mayak radiochemical plant for the manufacture of bomb plutonium into the river. A total of 76x10 6 m 3 liquid waste with a total activity of 2,75x10 6 Ci was discharged into the river from 1949 to 1956. The population of villages on the banks of the river, 26554 subjects was exposed to external and internal radiation. The doses per gonads caused by external exposure and incorporation of evenly distributed radionuclides (mainly 137 Cs) ranged 20 to 1270 mSv. A total of 23869 children were born to exposed subjects since the beginning of exposure; 3160 of these were exposed in utero. The mortality rates int he studied cohort was nothigher than in controls. However, deaths from the so-called endogenous causes were more frequent for the descendants of exposed subjects: neonatal diseases, congenital developmental defects, and states that could not be accurately defined. Correlation of the number of deaths from congenital developmental defects to the collective gonadal dose permitted us to assess the risk as 0.004 perSv, this being in agreement with the estimates of the International Committee for Radiation Protection. 7 refs.; 2 figs.; 6 tabs

Stability of people exposed to water flows

Directory of Open Access Journals (Sweden)

E. Martínez-Gomariz

2016-01-01

Full Text Available Our cities are formed by several elements which are exposed to floods of a magnitude according to the importance of the rainfall event and the design of the urban drainage system. The most important components in the cities are the pedestrians who develop various activities during rain events. Focusing on pedestrians, the research on their stability when they are exposed to water flows provides the necessary knowledge to understand and manage the associated hazard for them. In this research, several experiments with humans were carried out in order to determine the stability limits to pedestrians crossing through a water flow in a real scale platform. The results obtained and by comparing those with human stability criteria proposed by other authors and guidelines provide a more restrictive criterion.

Chromosome aberrations in pesticide-exposed greenhouse workers

DEFF Research Database (Denmark)

Lander, B F; Knudsen, Lisbeth E.; Gamborg, M O

2000-01-01

OBJECTIVES: The aim of this study was to investigate the possibility of subtoxic exposure to pesticides causing chromosome aberrations in greenhouse workers. METHODS: In a cross-sectional and prospective study design chromosome aberration frequencies in cultured lymphocytes were examined for 116...... greenhouse workers exposed to a complex mixture of almost 50 insecticides, fungicides, and growth regulators and also for 29 nonsmoking, nonpesticide-exposed referents. RESULTS: The preseason frequencies of chromosome aberrations were slightly but not statistically significantly elevated for the greenhouse...... workers when they were compared with the referents. After a summer season of pesticide spraying in the greenhouses, the total frequencies of cells with chromosome aberrations were significantly higher than in the preseason samples (P=0.02) and also higher than for the referents (P=0.05). This finding...

Effects of lead on the visual system of occupationally exposed subjects

Energy Technology Data Exchange (ETDEWEB)

Cavalleri, A.; Trimarchi, F.; Gelmi, C.; Baruffini, A.; Minoia, C.; Biscaldi, G.; Gallo, G.

1982-01-01

A quantitative measurement of visual field in mesopic adaptation was performed for 35 workers occupationally exposed to lead and 35 referents matched for age, smoking, and alcohol consumption. The mean level (+/- SD) of lead in blood was 47 +/- 16 microgram/100 ml (2.25 +/- 0.77 mumol/l) (range 21-82 microgram/100 ml (1.01-3.94 mumol/l)). In 10 exposed subjects a central scotoma was found that was not evidenced in any of the referents. A highly significant decrease in visual sensitivity was observed for the exposed subjects a central scotoma was found that was not evidenced in any of the referents. A highly significant decrease in visual sensitivity was observed for the exposed subjects. The results point to damage of central and peripheral optic nerve fibers. In the most severe cases, central vision is preferentially affected, and therefore the results are suggestive of subclinical optic neuropathy.

Dose coefficients for individual occupationally exposed

International Nuclear Information System (INIS)

2005-11-01

This Regulation refers to the requirements of the Regulation CNEN-NN.3.01, 'Basic Act of Radiological Protection', aiming its application to the dose calculation, with purposes of conformity verification with limits and restrictions of doses and level of reference for individual occupationally exposed, according to the express in its section 5

Effect of acetaminophen administration to rats chronically exposed to depleted uranium

International Nuclear Information System (INIS)

Gueguen, Y.; Grandcolas, L.; Baudelin, C.; Grison, S.; Tissandie, E.; Jourdain, J.R.; Paquet, F.; Voisin, P.; Aigueperse, J.; Gourmelon, P.; Souidi, M.

2007-01-01

The extensive use of depleted uranium (DU) in both civilian and military applications results in the increase of the number of human beings exposed to this compound. We previously found that DU chronic exposure induces the expression of CYP enzymes involved in the metabolism of xenobiotics (drugs). In order to evaluate the consequences of these changes on the metabolism of a drug, rats chronically exposed to DU (40 mg/l) were treated by acetaminophen (APAP, 400 mg/kg) at the end of the 9-month contamination. Acetaminophen is considered as a safe drug within the therapeutic range but in the case of overdose or in sensitive animals, hepatotoxicity and nephrotoxicity could occur. In the present work, plasma concentration of APAP was higher in the DU group compared to the non-contaminated group. In addition, administration of APAP to the DU-exposed rats increased plasma ALT (p < 0.01) and AST (p < 0.05) more rapidly than in the control group. Nevertheless, no histological alteration of the liver was observed but renal injury characterized by incomplete proximal tubular cell necrosis was higher for the DU-exposed rats. Moreover, in the kidney, CYP2E1 gene expression, an important CYP responsible for APAP bioactivation and toxicity, is increased (p < 0.01) in the DU-exposed group compared to the control group. In the liver, CYP's activities were decreased between control and DU-exposed rats. These results could explain the worse elimination of APAP in the plasma and confirm our hypothesis of a modification of the drug metabolism following a DU chronic contamination

Cytogenetic investigation of subjects professionally exposed to radiofrequency radiation.

Science.gov (United States)

Maes, Annemarie; Van Gorp, Urbain; Verschaeve, Luc

2006-03-01

Nowadays, virtually everybody is exposed to radiofrequency radiation (RFR) from mobile phone base station antennas or other sources. At least according to some scientists, this exposure can have detrimental health effects. We investigated cytogenetic effects in peripheral blood lymphocytes from subjects who were professionally exposed to mobile phone electromagnetic fields in an attempt to demonstrate possible RFR-induced genetic effects. These subjects can be considered well suited for this purpose as their RFR exposure is 'normal' though rather high, and definitely higher than that of the 'general population'. The alkaline comet assay, sister chromatid exchange (SCE) and chromosome aberration tests revealed no evidence of RFR-induced genetic effects. Blood cells were also exposed to the well known chemical mutagen mitomycin C in order to investigate possible combined effects of RFR and the chemical. No cooperative action was found between the electromagnetic field exposure and the mutagen using either the comet assay or SCE test.

Zirconium ignition in exposed fuel channel

Energy Technology Data Exchange (ETDEWEB)

Elias, E., E-mail: merezra@technion.ac.il; Hasan, D.; Nekhamkin, Y.

2015-05-15

Highlights: • We demonstrate the idea of runaway zirconium–steam reactions in severe accidents in today's LWRs. • We predict the thermal-hydraulics conditions relevant to cladding oxidation in an exposed fuel channel of a partially uncovered core. • The Semenov theory of metal combustion is extended to define a criterion for runaway oxidation reaction in fuel cladding. - Abstract: A theoretical model based on simultaneous solution of the heat and mass transfer equations is developed for predicting the rate of thermo-chemical reaction between zirconium cladding and a hot steam environment. Ignition conditions relevant to cladding oxidation in an exposed fuel channel of a partially uncovered core are predicted based on the theory of metal combustion. A range of decay power, convective heat transfer coefficients, and initial temperatures leading to uncontrolled runaway cladding oxidation is identified. The model could be readily integrated as part of a fuel channel analysis code for predicting possible outcomes of different accident mitigation procedures in light water nuclear reactors under LOCA conditions.

One-stage explant-implant procedure of exposed porous orbital implants

DEFF Research Database (Denmark)

Toft, Peter B; Rasmussen, Marie L Roed; Prause, Jan Ulrik

2011-01-01

Purpose:  To investigate the risks of implant exposure after a combined explant-implant procedure in patients with an exposed porous orbital implant. Methods:  Twenty-four consecutive patients who had a combined explant-implant procedure of an exposed hydroxyapatite (21) or porous polyethylene (3...... at the same procedure in sockets without profound signs of infection. The procedure carries a possible risk of poor motility....

Survey of studies of occupational populations exposed to low-level radiation

International Nuclear Information System (INIS)

Marks, S.

1980-04-01

Studies of occupational populations exposed to large doses of radiation, principally from the ingestion of radium by dial painters and inhalation of radon and its daughters by miners, have provided important information on the health effects of those radioisotopes. Studies of medical radiologists, military personnel exposed to nuclear tests, and factory workers exposed to thorium are in progress. Employees of DOE-contractor facilities and of naval shipyards are also under study. Personnel dosimetry data are generally available for the latter category of occupational populations. Reasons for conducting the studies include interest in exploring the verification at low exposure levels of results of studies of heavily exposed populations and the responsibility of the employer to maintain adequate surveillance of the health of his workers by conducting appropriate epidemiologic studies. The low level of exposure of workers in facilities where adequate personnel dosimetry records are available make it unlikely that the results of such studies can be used to provide health risk estimates in the near future

Metabolic signature of sun exposed skin suggests catabolic pathway overweighs anabolic pathway.

Directory of Open Access Journals (Sweden)

Manpreet Randhawa

Full Text Available Skin chronically exposed to sun results in phenotypic changes referred as photoaging. This aspect of aging has been studied extensively through genomic and proteomic tools. Metabolites, the end product are generated as a result of biochemical reactions are often studied as a culmination of complex interplay of gene and protein expression. In this study, we focused exclusively on the metabolome to study effects from sun-exposed and sun-protected skin sites from 25 human subjects. We generated a highly accurate metabolomic signature for the skin that is exposed to sun. Biochemical pathway analysis from this data set showed that sun-exposed skin resides under high oxidative stress and the chains of reactions to produce these metabolites are inclined toward catabolism rather than anabolism. These catabolic activities persuade the skin cells to generate metabolites through the salvage pathway instead of de novo synthesis pathways. Metabolomic profile suggests catabolic pathways and reactive oxygen species operate in a feed forward fashion to alter the biology of sun exposed skin.

Cytokine mRNA profiles in pigs exposed prenatally and postnatally to Schistosoma japonicum

DEFF Research Database (Denmark)

Techau, Michala E.; Johansen, Maria V.; Aasted, Bent

2007-01-01

of septal fibrosis were significantly higher in the postnatal group compared to the prenatal group (P prenatally infected animals compared to the control...... group (P prenatal group showed higher levels of TGF-beta 1 in the liver compared with the postnatally infected group (P control group (P prenatally exposed pigs.......The pig is a natural host for Schistosoma japonicum and a useful animal model of human infection. The aim of the present study was to assess the differences between the cytokine profiles in prenatally or postnatally S. japonicum exposed pigs. Seven prenatally exposed pigs, 7 postnatally exposed...

Frequency of marriage and live birth among survivors prenatally exposed to the atomic bomb

International Nuclear Information System (INIS)

Blot, W.J.; Shimizu, Y.; Kato, H.; Miller, R.W.

1975-01-01

Frequency of marriage and birth as of January 1973 was determined for persons exposed in utero to the atomic bombs in 1945 and for controls. The marriage rate was lower in persons heavily exposed in utero than in the non-exposed or lightly exposed. This difference is attributed partly to the lesser marriageability of persons with mental retardation who are significantly more numerous among the heavily exposed, and partly to unmeasured variables, possibly including social discrimination against survivors of the atomic bomb. No consistent relation was observed between radiation exposure and three reproductive indices: childless marriages, number of births, and interval between marriage and first birth

Increased lung function decline in blue-collar workers exposed to welding fumes.

Science.gov (United States)

Thaon, Isabelle; Demange, Valérie; Herin, Fabrice; Touranchet, Annie; Paris, Christophe

2012-07-01

There is no consensus at the present time about the effect of welding on lung function decline. This study compared lung function decline between blue-collar workers exposed and not exposed to welding fumes in a French longitudinal cohort of 21,238 subjects aged 37 to 52 years at inclusion. Medical data, occupation, sector of activity, and spirometry were recorded twice by occupational physicians in 1990 and 1995. A job-exposure matrix was used to identify 503 male blue-collar workers exposed to welding fumes and 709 control subjects and to define the weekly duration of exposure to welding fumes. Baseline lung function parameters were higher in workers exposed to welding fumes than in control subjects. After a 5-year follow-up, welding-fume exposure was associated with a nonsignificant decline in FVC (P = .06) and FEV(1) (P = .07) after adjustment for age, pack-years, BMI, and baseline value of the parameter. A significant accelerated decline in FEV(1) (P = .046) was also observed in never smokers exposed to welding fumes. An “exposure-response” relationship was observed between FEV(1) decline and weekly duration of exposure to welding fumes in nonsmokers but not in smokers. Blue-collar workers exposed to welding fumes showed accelerated decline in lung function, which, in nonsmokers, was related to weekly duration of exposure.

Study of External Radiation Expose Dose on Hands of Nuclear Medicine Workers

International Nuclear Information System (INIS)

Park, Jun Chul; Pyo, Sung Jae

2012-01-01

The aims of this study are to assess external radiation exposed doses of body and hands of nuclear medicine workers who handle radiation sources, and to measure radiation exposed doses of the hands induced by a whole body bone scan with high frequency and handling a radioactive sources like 99m Tc-HDP and 18 F-FDG in the PET/CT examination. Skillful workers, who directly dispense and inject from radiation sources, were asked to wear a TLD on the chest and ring finger. Then, radiation exposed dose and duration exposed from daily radiation sources for each section were measured by using a pocket dosimeter for the accumulated external doses and the absorbed dose to the hands. In the survey of four medical institutions in Incheon Metropolitan City, only one of four institutions has a radiation dosimeter for local area like hands. Most of institutions uses radiation shielding devices for the purpose of protecting the body trunk, not local area. Even some institutions were revealed not to use such a shielding device. The exposed doses on the hands of nuclear medicine workers who directly handles radioactive sources were approximately twice as much as those on the body. The radiation exposure level for each section of the whole body bone scan with high frequency and that of the PET/CT examination showed that radiation doses were revealed in decreasing order of synthesis of radioactive medicine and installation to a dispensing container, dispensing, administering and transferring. Furthermore, there were statistically significant differences of radiation exposure doses of the hands before and after wearing a syringe shielder in administration of a radioactive sources. In this study, although it did not reach the permissible effective dose for nuclear medicine, the occupational workers were exposed by relatively higher dose level than the non-occupational workers. Therefore, the workers, who closely exposed to radioactive sources should be in compliance with safety

Methylomic changes in individuals with psychosis, prenatally exposed to endocrine disrupting compounds: Lessons from diethylstilbestrol.

Directory of Open Access Journals (Sweden)

Fabrice Rivollier

Full Text Available In the Western world, between 1940 and 1970, more than 2 million people were exposed in utero to diethylstilbestrol (DES. In exposed individuals, and in their descendants, adverse outcomes have been linked to such exposure, including cancers, genital malformations, and less consistently, psychiatric disorders. We aimed to explore whether prenatal DES exposure would be associated with DNA methylation changes, and whether these epigenetic modifications would be associated with increased risk of psychosis.From 247 individuals born from mothers exposed to DES, we selected 69 siblings from 30 families. In each family, at least one sibling was exposed in utero to DES. We performed a methylome-wide association study using HumanMethylation450 DNA Analysis BeadChip® in peripheral blood. We analyzed methylation changes at individual CpGs or regions in exposed (n = 37 versus unexposed individuals (n = 32. We also compared exposed individuals with (n = 7 and without psychosis (n = 30.There were more individuals with schizophrenia in the DES-exposed group. We found no significant differences between exposed and unexposed individuals with respect to differentially methylated CpGs or regions. The largest difference was in a region near the promoter of an ADAMTS proteoglycanase gene (ADAMTS9. Compared to exposed individuals without psychosis, exposed individuals with psychosis had differential methylation in the region encompassing the gene encoding the zinc finger protein 57 (ZFP57.In utero exposure to DES was not associated with methylation changes at specific CpG or regions. In exposed individuals, however, psychosis was associated with specific methylomic modifications that could impact neurodevelopment and neuroplasticity.

Color discrimination impairment in workers exposed to mercury vapor.

Science.gov (United States)

Urban, Pavel; Gobba, Fabriziomaria; Nerudová, Jana; Lukás, Edgar; Cábelková, Zdena; Cikrt, Miroslav

2003-08-01

To study color discrimination impairment in workers exposed to elemental mercury (Hg) vapor. Twenty-four male workers from a chloralkali plant exposed to Hg vapor, aged 42+/-9.8 years, duration of exposure 14.7+/-9.7 years, were examined. The 8h TWA air-borne Hg concentration in workplace was 59 microg/m(3); mean Hg urinary excretion (HgU) was 20.5+/-19.3 microg/g creatinine; mean Hg urinary excretion after the administration of a chelating agent, sodium 2,3-dimercapto-1-propane-sulfonate (DMPS), was 751.9+/-648 microg/48h. Twenty-four age- and gender-matched control subjects were compared. Visual acuity, alcohol intake, smoking habits, and history of diseases or drugs potentially influencing color vision were registered. The Lanthony 15-Hue desaturated test (L-D15-d) was used to assess color vision. The results were expressed quantitatively as Bowman's Color Confusion Index (CCI), and qualitatively according to Verriest's classification of acquired dyschromatopsias. The CCI was significantly higher in the exposed group than in the control (mean CCI 1.15 versus 1.04; P=0.04). The proportion of subjects with errorless performance on the Lanthony test was significantly lower in the Hg exposed group compared to referents (52% versus 73%; P=0.035). The exposed group showed higher frequency of type III dyschromatopsias (blue-yellow confusion axis) in comparison with the control group (12.5% versus 8.3%), however, the difference did not reach statistical significance. Multiple regression did not show any significant relationship between the CCI, and age, alcohol consumption, or measures of exposure. In agreement with previous studies by Cavalleri et al. [Toxicol. Lett. 77 (1995) 351; Environ. Res. Sec. A 77 (1998) 173], the results of this study support the hypothesis that exposure to mercury vapor can induce sub-clinical color vision impairment. This effect was observed at an exposure level below the current biological limit for occupational exposure to mercury. This

Influence of Some Pesticides on Humoral and Cellular Immunity of Exposed Workers in Pesticides Industries

International Nuclear Information System (INIS)

Osely, E.Sh.M.

2010-01-01

Pesticide poisoning is a major public health problem in developing countries. In most of these countries organophosphate pesticides constitute the most widely used pesticides. The main toxicity of OPs is neurotoxicity, which is caused by the inhibition of acetylcholinesterase. OPs also affect the immune response, including effects on cellular and humoral immunity. Our study examined the effect of organophosphorus compounds on humoral and cellular immunity of exposed workers in pesticides industries. The study was conducted into 40 subjects. They were 2 groups; 20 exposed workers from Gharbeia and Kafr Elsheikh at 2008 and 2009 and 20 unexposed individuals as a control group at the same period of time. We examined some immune parameters; pseudocholinesterase, WBCs count, CD4%, CD8%, CD4/CD8, CD56%, Interleukin 2, IgG and IgM. Also we take history and clinical examination for them. We reported a highly significant decrease in pseudo cholinesterase level among the exposed group in comparison to the control group, highly significant increase in percentage of CD8 in the exposed group in comparison to control group, highly significant decrease in CD4 / CD8 ratio in the exposed group in comparison to control group, highly significant decrease in percentage of CD56 in the exposed group in comparison to control group and a highly significant increase in IgG level in the exposed group in comparison to control group. On the other hand, we reported no significant change in white blood cells count between the exposed and control groups, no significant change in percentage of CD4 among the exposed and control group, no significant change in Interleukin 2 level among the exposed and control group and no significant change in IgM level among the exposed and control group. We concluded that pesticides extensively affect the humoral and cellular immune system of occupationally exposed workers.

Fracture behaviour of the 14Cr ODS steel exposed to helium and liquid lead

Energy Technology Data Exchange (ETDEWEB)

Hojna, Anna, E-mail: Anna.Hojna@cvrez.cz [Centrum Vyzkumu Rez s.r.o., UJV Group, Rez 130, 250 68 Husinec (Czech Republic); Di Gabriele, Fosca [Centrum Vyzkumu Rez s.r.o., UJV Group, Rez 130, 250 68 Husinec (Czech Republic); Hadraba, Hynek; Husak, Roman; Kubena, Ivo [CEITEC IPM, Institute of Physics of Materials, Academy of Sciences of the Czech Republic, Zizkova 22, 616 62 Brno (Czech Republic); Rozumova, Lucia; Bublikova, Petra; Kalivodova, Jana [Centrum Vyzkumu Rez s.r.o., UJV Group, Rez 130, 250 68 Husinec (Czech Republic); Matejicek, Jiri [Institute of Plasma Physics, Academy of Sciences of the Czech Republic, Za Slovankou 1782/3, 182 00 Praha (Czech Republic)

2017-07-15

This work describes the fracture behaviour of the 14Cr ODS steel produced by mechanical alloying process, after high temperature exposures. Small specimens were exposed to helium gas in a furnace at 720 °C for 500 h. Another set of specimens was exposed to flowing liquid lead in the COLONRI II loop at 650 °C for 1000 h. All specimens were tested for the impact and tensile behaviour. The impact test results are compared to other sets of specimens in the as received state and after isothermal annealing at 650 °C for 1000 h. The impact curves of the exposed materials showed positive shifts on the transition temperature. While the upper shelf value did not change in the Pb exposed ODS steel, it significantly increased in the He exposed one. The differences are discussed in terms of surface and subsurface microscopy observation. The embrittlement can be explained as the effect of a slight change in the grain boundary and size distribution combined with the depletion of sub-surface region from alloying elements forming oxide scale on the surface. - Highlights: •We compared the impact energy curves of as received, isothermally aged and He/Pb exposed ODS steel samples. •The highest transition temperature showed the ODS steel exposed to liquid Pb at 650 °C for 1000 h. •We observed the higher tendency of the He exposed samples to crack arrester delamination than the Pb exposed ones. •The crack arrested delamination induced apparent increase of impact energies.

[Cognitive impairments in persons exposed to radiation during the period of prenatal development].

Science.gov (United States)

Burtovaya, E Yu; Kantina, T E; Belova, M V; Akleyev, A V

2015-01-01

To assess the cognitive status in persons exposed to ionizing radiation in prenatal period. The study included in-utero exposed people (n = 77), and the comparison group (n = 73), which consisted of people who lived in the territories of the Chelyabinsk Oblast that were not radioactive. The following methods were used: clinical, clinical-psychological (Mini-Mental State Examination (MMSE), the WAIS test, the proverb interpretation task, neurophysiological (EEG) methods, laboratory-based methods (cholesterol, high and low-density lipoproteins, triglycerides, cortisol, melatonin), and methods of statistical data processing. The number of people with non-psychotic mental disorders with the prevalence of organic mental disorders (cognitive and asthenic) was significantly higher among in-utero exposed subjects. A neurophysiological study revealed more severe changes in the bioelectric brain activity with the presence of pathological and theta-rhythms in exposed persons. The clinical-psychological study revealed a significant decrease in the analytic/synthetic ability in exposed people and significantly lower level of the general and verbal IQ. These changes were accompanied by higher levels of cortisol and melatonin which led to the activation and tension of the adaptation mechanisms in in-utero exposed subjects.

Micronuclei frequency in albino rats exposed to high natural radiation

International Nuclear Information System (INIS)

Aneesh, D.; Godwin Wesley, S.

2013-01-01

Genotoxicity and DNA damage endpoints are used to evaluate results in the context of cell survival. Genotoxicity in mammalian cells is monitored mostly by using cytokinesis-block micronucleus (CBMN) assay. The score of micronuclei (MN) in peripheral blood lymphocytes can be used as a biomarker and also as a bio-dosimeter of radiation exposure. In the present study the effect of natural radiation on albino rats has been investigated, to find out if there is any increase in MN frequency in peripheral blood lymphocytes. Animals at the age of 2-3 weeks were exposed to natural radiation, at the dose of 10.38 μGyh -1 for a period of 6 months. A parallel control set was also maintained (0.12 μGy h -1 '). Blood samples were collected from both test (exposed to natural radiation) and control rats. Lymphocyte culture was done following 'microculture techniques' for 72 h. Cytochalasin B, at a concentration of 6.0 μg/ml, was added to the lymphocyte cultures at 44 h to block cytokinesis. The frequency of MN was evaluated by scoring a total of 1000 binucleated (BN) cells from one slide. The frequency of MN among the rats exposed to natural radiation was found to be 1.83±0.05 per 1000 BN cells and in the control it was 1.82±0.07 per 1000 BN cells. No statistically significant difference in the MN frequencies of exposed and control groups (p>0.05) was seen. The lower MN frequency in natural radiation exposed rats could be an indication of adaptive response. (author)

Measurement of DNA repair deficiency in workers exposed to benzene

International Nuclear Information System (INIS)

Hallberg, L.M.; Au, W.W.; El Zein, R.; Grossman, L.

1996-01-01

We hypothesize that chronic exposure to environmental toxicants can induce genetic damage causing DNA repair deficiencies and leading to the postulated mutator phenotype of carcinogenesis. To test our hypothesis, a host cell reactivation (HCR) assay was used in which pCMVcat plasmids were damaged with UV light (175, 350 J/m 2 UV light), inactivating the chloramphenicol acetyltransferase reporter gene, and then transfected into lymphocytes. Transfected lymphocytes were therefore challenged to repair the damaged plasmids, reactivating the reporter gene. Xeroderma pigmentosum (XP) and Gaucher cell lines were used as positive and negative controls for the HCR assay. The Gaucher cell line repaired normally but XP cell lines demonstrated lower repair activity. Additionally, the repair activity of the XP heterozygous cell line showed intermediate repair compared to the homozygous XP and Gaucher cells. We used HCR to measure the effects of benzene exposure on 12 exposed and 8 nonexposed workers from a local benzene plant. Plasmids 175 J/m 2 and 350 J/m 2 were repaired with a mean frequency of 66% and 58%, respectively, in control workers compared to 71% and 62% in exposed workers. Conversely, more of the exposed workers were grouped into the reduced repair category than controls. These differences in repair capacity between exposed and control workers were, however, not statistically significant. The lack of significant differences between the exposed and control groups may be due to extremely low exposure to benzene (<0.3 ppm), small population size, or a lack of benzene genotoxicity at these concentrations. These results are consistent with a parallel hprt gene mutation assay. 26 refs., 4 figs., 2 tabs

Contribution to the problem of biological dose assessment in occupationally exposed personnel

International Nuclear Information System (INIS)

Anger, H.; Jacobsohn, E.

1976-01-01

Chromosome studies were made on lymphocytes taken from the peripheral blood of occupationally exposed personnel (4 groups, exposure < 5 rems). In all exposed individuals the rate of aberration was found to be higher compared to the controls, with maximum values observed in those who had been additionally exposed to acute partial body irradiation. In order to get statistically significant differences over the controls, it is necessary, however, to calculate the frequency of the various aberrations in terms of a 'point system' rather than in per cent. (author)

Exposing Library Services with AngularJS

OpenAIRE

Jakob Voß; Moritz Horn

2014-01-01

This article provides an introduction to the JavaScript framework AngularJS and specific AngularJS modules for accessing library services. It shows how information such as search suggestions, additional links, and availability can be embedded in any website. The ease of reuse may encourage more libraries to expose their services via standard APIs to allow usage in different contexts.

Stabilizer for seismically exposed bridge cranes

International Nuclear Information System (INIS)

Engelke, M.; Kuhr, H.

1982-01-01

The invention concerns a stabilizer for seismically exposed bridge cranes in reactor buildings. The trolley and the crane bridge are fitted with the stabilizer consisting of a bipartite safety catch which is connected with a joint and able to take up the vertical loads during an earthquake. This stabilizer is suitable for all kinds of bridge cranes operated in seismically active regions

Rapid genetic erosion in pollutant-exposed experimental chironomid populations

Energy Technology Data Exchange (ETDEWEB)

Nowak, Carsten [Abteilung Okologie und Evolution, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: cnowak@senckenberg.de; Vogt, Christian [Abteilung Aquatische Okotoxikologie, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: vogt@bio.uni-frankfurt.de; Pfenninger, Markus [Abteilung Okologie und Evolution, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: pfenninger@bio.uni-frankfurt.de; Schwenk, Klaus [Abteilung Okologie und Evolution, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: k.schwenk@bio.uni-frankfurt.de; Oehlmann, Joerg [Abteilung Aquatische Okotoxikologie, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: oehlmann@bio.uni-frankfurt.de; Streit, Bruno [Abteilung Okologie und Evolution, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: streit@bio.uni-frankfurt.de; Oetken, Matthias [Abteilung Aquatische Okotoxikologie, Institut fuer Okologie, Evolution und Diversitaet, J. W. Goethe-Universitaet Frankfurt am Main, Siesmayerstrasse 70, 60054 Frankfurt am Main (Germany)], E-mail: oetken@bio.uni-frankfurt.de

2009-03-15

Few studies have evaluated how effectively environmental contamination may reduce genetic diversity of a population. Here, we chose a laboratory approach in order to test if tributyltin (TBT) exposure at environmentally relevant concentrations leads to reduced genetic variation in the midge Chironomus riparius. Two TBT-exposed and two unexposed experimental populations were reared simultaneously in the laboratory for 12 generations. We recorded several life-history traits in each generation and monitored genetic variation over time using five variable microsatellite markers. TBT-exposed strains showed increased larval mortality (treatments: 43.8%; controls: 27.8%), slightly reduced reproductive output, and delayed larval development. Reduction of genetic variation was strongest and only significant in the TBT-exposed strains (treatments: -45.9%, controls: -24.4% of initial heterozygosity) after 12 generations. Our findings document that chemical pollution may lead to a rapid decrease in genetic diversity, which has important implications for conservation strategies and ecological management in polluted environments. - Chronic TBT exposure reduces allelic variation at five variable microsatellite loci in experimental populations of Chironomus riparius.

Rapid genetic erosion in pollutant-exposed experimental chironomid populations

International Nuclear Information System (INIS)

Nowak, Carsten; Vogt, Christian; Pfenninger, Markus; Schwenk, Klaus; Oehlmann, Joerg; Streit, Bruno; Oetken, Matthias

2009-01-01

Few studies have evaluated how effectively environmental contamination may reduce genetic diversity of a population. Here, we chose a laboratory approach in order to test if tributyltin (TBT) exposure at environmentally relevant concentrations leads to reduced genetic variation in the midge Chironomus riparius. Two TBT-exposed and two unexposed experimental populations were reared simultaneously in the laboratory for 12 generations. We recorded several life-history traits in each generation and monitored genetic variation over time using five variable microsatellite markers. TBT-exposed strains showed increased larval mortality (treatments: 43.8%; controls: 27.8%), slightly reduced reproductive output, and delayed larval development. Reduction of genetic variation was strongest and only significant in the TBT-exposed strains (treatments: -45.9%, controls: -24.4% of initial heterozygosity) after 12 generations. Our findings document that chemical pollution may lead to a rapid decrease in genetic diversity, which has important implications for conservation strategies and ecological management in polluted environments. - Chronic TBT exposure reduces allelic variation at five variable microsatellite loci in experimental populations of Chironomus riparius

Increased oxidative stress in infants exposed to passive smoking.

Science.gov (United States)

Aycicek, Ali; Erel, Ozcan; Kocyigit, Abdurrahim

2005-12-01

The purpose of this study was to assess the effect of passive cigarette smoking on the oxidative and anti-oxidative status of plasma in infants. Eighty-four infants aged 6-28 weeks were divided into two groups: the study group included infants who had been exposed to passive smoking via at least five cigarettes per day for at least the past 6 weeks at home, while the control group included infants who had never been exposed to passive smoking. The antioxidative status of plasma was assessed by the measurement of individual antioxidant components: vitamin C, albumin, bilirubin, uric acid, thiol contents and total antioxidant capacity (TAC 1 and TAC 2). Oxidative status was assessed by the determination of total peroxide levels and the oxidative stress index (OSI 1 and OSI 2). Plasma vitamin C, thiol concentration and TAC 1 and TAC 2 levels were significantly lower, whereas plasma total peroxide levels and OSI 1 and OSI 2 were significantly higher, in passive smoking infants than in the controls (Pantioxidant defence system in infants, and exposes them to potent oxidative stress.

Differential pattern of deposition of nanoparticles in the airways of exposed workers

Energy Technology Data Exchange (ETDEWEB)

Fireman, Elizabeth, E-mail: fireman@tlvmc.gov.il [Tel Aviv University, Laboratory of Pulmonary and Allergic Diseases (Israel); Edelheit, Rinat [Tel Aviv University, Department of Occupational and Environmental Health School of Public Health, Sackler Faculty of Medicine (Israel); Stark, Moshe [Tel Aviv University, Laboratory of Pulmonary and Allergic Diseases (Israel); Shai, Amir Bar [Tel Aviv University, Pulmonology Department, Tel-Aviv Sourasky Medical Center affiliated to the Sackler Faculty of Medicine (Israel)

2017-02-15

Ultrafine particles (UFP) have been postulated to significantly contribute to the adverse health effects associated with exposure to particulate matter (PM). Due to their extremely small size (aerodynamic diameter <100 nm), UFP are able to deposit deep within the lung after inhalation and evade many mechanisms responsible for the clearance of larger particles. There is a lack of biologically relevant personal exposure metrics for exposure to occupational- and environmental-related micro- and nano-sized PM. The aim of the present study is to assess UFP in induced sputum (IS) and exhaled breath condensate (EBC) as possible biomarkers for assessing lung function impairment. Sputum induction and EBC testing were performed by conventional methods. UFP particles were assessed with the NanoSight LM20 (NanoSight Ltd, London, UK). The subjects included 35 exposed and 25 non-exposed workers. There were no group differences in pulmonary function test results and differential cell counts, but 63.6% of the exposed subjects had a higher percentage of neutrophils (OR3.28 p = 0.03) compared to the non-exposed subjects. The exposed subjects had higher percentages of UFP between 10 and 50 nm (69.45 ± 18.70 vs 60.11 ± 17.52 for the non-exposed group, p = 0.004). No differences were found in the IS samples. Years of exposure correlated positively to UFP content (r = 0.342 p = 0.01) and macrophage content (r = −0.327 p = 0.03). The percentage of small fraction of UFP in EBC, but not IS, is higher in exposed workers, and EBC may be a sensitive biomarker to assess exposure to nanoparticles.

Induction of adaptive response in human blood lymphocytes exposed to radiofrequency radiation.

Science.gov (United States)

Sannino, Anna; Sarti, Maurizio; Reddy, Siddharth B; Prihoda, Thomas J; Vijayalaxmi; Scarfì, Maria Rosaria

2009-06-01

The incidence of micronuclei was evaluated to assess the induction of an adaptive response to non-ionizing radiofrequency (RF) radiation in peripheral blood lymphocytes collected from five different human volunteers. After stimulation with phytohemagglutinin for 24 h, the cells were exposed to an adaptive dose of 900 MHz RF radiation used for mobile communications (at a peak specific absorption rate of 10 W/kg) for 20 h and then challenged with a single genotoxic dose of mitomycin C (100 ng/ml) at 48 h. Lymphocytes were collected at 72 h to examine the frequency of micronuclei in cytokinesis-blocked binucleated cells. Cells collected from four donors exhibited the induction of adaptive response (i.e., responders). Lymphocytes that were pre-exposed to 900 MHz RF radiation had a significantly decreased incidence of micronuclei induced by the challenge dose of mitomycin C compared to those that were not pre-exposed to 900 MHz RF radiation. These preliminary results suggested that the adaptive response can be induced in cells exposed to non-ionizing radiation. A similar phenomenon has been reported in cells as well as in animals exposed to ionizing radiation in several earlier studies. However, induction of adaptive response was not observed in the remaining donor (i.e., non-responder). The incidence of micronuclei induced by the challenge dose of mitomycin C was not significantly different between the cells that were pre-exposed and unexposed to 900 MHz RF radiation. Thus the overall data indicated the existence of heterogeneity in the induction of an adaptive response between individuals exposed to RF radiation and showed that the less time-consuming micronucleus assay can be used to determine whether an individual is a responder or non-responder.

Intracellular free calcium concentration and calcium transport in human erythrocytes of lead-exposed workers

International Nuclear Information System (INIS)

Quintanar-Escorza, M.A.; Gonzalez-Martinez, M.T.; Navarro, L.; Maldonado, M.; Arevalo, B.; Calderon-Salinas, J.V.

2007-01-01

Erythrocytes are the route of lead distribution to organs and tissues. The effect of lead on calcium homeostasis in human erythrocytes and other excitable cells is not known. In the present work we studied the effect of lead intoxication on the uptake and efflux (measured as (Ca 2+ -Mg 2+ )-ATPase activity) of calcium were studied in erythrocytes obtained from lead-exposed workers. Blood samples were taken from 15 workers exposed to lead (blood lead concentration 74.4 ± 21.9 μg/dl) and 15 non-exposed workers (9.9 ± 2 μg/dl). In erythrocytes of lead-exposed workers, the intracellular free calcium was 79 ± 13 nM, a significantly higher concentration (ANOVA, P 2+ -Mg 2+ )-ATPase activity. Lipid peroxidation was 1.7-fold higher in erythrocytes of lead-exposed workers as compared with control. The alteration on calcium equilibrium in erythrocytes is discussed in light of the toxicological effects in lead-exposed workers

Oxidative stress biomarkers and aggressive behavior in fish exposed to aquatic cadmium contamination

Directory of Open Access Journals (Sweden)

Jeane A. Almeida

Full Text Available The objective of this study was to investigate the possible link between cadmium exposure, hepatic markers of oxidative stress and aggressive behavior in Nile tilapia (Oreochromis niloticus. Fish were first exposed to 0.75 mg/L CdCl2 for 15 days (12 isolated fish for each group and afterward a behavioral test was performed. Fish from the control and cadmium-exposed groups were paired for 1 h (6 pairs of fish per group for determination of aggressiveness parameters. Immediately after the behavioral test, the animals were sacrificed and the liver was used to determine biochemical parameters. Cadmium decreased aggression in Nile tilapia. Subordinate animals exposed to cadmium showed decreased glutathione peroxidase (GSH-Px activity compared to dominant ones. No alterations were observed in selenium-dependent glutathione peroxidase Se-GSH-P and Cu-Zn superoxide dismutase activities, but total superoxide dismutase activity was increased in subordinate animals exposed to cadmium compared to subordinate control. Catalase activity was increased in cadmium-exposed fish. Lipoperoxide concentrations also increased in cadmium exposed fish indicating that cadmium toxicity may affect oxidative stress biomarkers in Nile tilapia. Social stress induced lipoperoxidation in Nile tilapia, and subordinate animals exposed to cadmium responded with lower activities of liver antioxidant enzymes compared to dominant fish. The present study shows that cadmium exposure is capable of inducing changes in the social status and oxidative stress parameters in this species.

Germline mutations in people descendants occupationally exposed to ionizing radiation from Cesium 137

International Nuclear Information System (INIS)

Silva, Juliana Ferreira da

2016-01-01

The radiological accident in Goiania in 1987, resulted in a serious episode of human contamination, animal, plant and environmental were exposed to Cesium 137 chloride ( 137 CsCl) that caused contamination and accidental and occupational exposure to ionizing radiation. Ionizing radiation is one of the environmental components that causes most cellular stress in complex organisms. Exposure to ionizing radiation induces breaks in nucleic acids, especially, DNA double and single strand breaks. Chromosomal microarray analysis is an important tool for the detection and microdeletion and microduplications in the genomes. In this study we proposed to analyze the effect of exposure to RI on the formation of CNVs in an exposed human population occupationally to ionizing radiation from Cesium 137 during the accident in Goiania. The exposed group consisted of 07 families, of which at least one parent was occupationally exposed to ionizing radiation from Cesium 137, including a total of 25 individuals, do not know the absorbed dose of the military who were occupationally exposed to ionizing radiation. 11 families with a group of individuals not exposed to IR was used as control were used including a total of 33 individuals with no history of exposure to RI. The genotyping microarray was conducted in CytoScan HD system (Affymetrix®) without then analyzes was performed in ChAS® software. The statistical tests used were: Shapiro-Wilk, Mann- Whitney U, Spearman correlation, discriminant function analysis, binomial test, χ 2 test. All analyzes were performed using the statistical package SPSS 21.0, with a significance level of 5% (p <0.05). The frequency of CNVs were estimated loss / generation, gain / generation and burden / generation, representing 3,9 x 10 -5 , 6,8 x 10 -6 and 4,6 x 10 -5 respectively for the exposed group. For the control group, the frequencies were 2,1 x 10 -5 , 5,9 x 10 -6 and 3,1 x 10 -5 respectively. Thus, the frequency of CNVs showed statistically

The potential DNA toxic changes among workers exposed to antimony trioxide.

Science.gov (United States)

El Shanawany, Safaa; Foda, Nermine; Hashad, Doaa I; Salama, Naglaa; Sobh, Zahraa

2017-05-01

Occupational exposure to antimony has gained much interest when specific toxic effects were noticed among workers processing antimony. Thus, the aim of the present work was to investigate the potential DNA oxidative damage occurring among Egyptian workers occupationally exposed to antimony trioxide. The study was conducted on 25 subjects exposed to antimony trioxide while working in the polymerization process of polyester in Misrayon and Polyester Fiber Company, KafrEldawwar, Beheira, Egypt. Urinary antimony levels were assessed using inductive coupled plasma-optical emission spectrometry (ICP-OES) and considered as a biological exposure index. DNA damage and total oxidant capacity (TOC) were assessed using ELISA. DNA damage was detected in the form of increased apurinic/apyrimidinic (AP) sites among antimony trioxide-exposed workers compared to control subjects, but it could not be explained by oxidative mechanisms due to lack of significant correlation between DNA damage and measured TOC. Antimony trioxide might have a genotoxic impact on occupationally exposed workers which could not be attributed to oxidative stress in the studied cases.

Corrosion of beryllium exposed to celotex and water

International Nuclear Information System (INIS)

Hill, M.A.; Butt, D.P.; Lillard, R.S.

1997-01-01

Celotex is a commercial rigid cellulose fiberboard product primarily used in the building construction industry. Currently celotex is being used as a packing material in AL-R8 containers. Ion chromatography of celotex packing material at Lawrence Livermore National Laboratory (LLNL) has indicated that this material contains aggressive anions, including chloride, which may accelerate corrosion. It is well known that beryllium is susceptible to pitting corrosion when exposed to chloride containing environments. Levy noted pitting in beryllium at the open circuit potential when exposed to 0.1 M NaCl solution. This investigation attempts to evaluate the potential risk of accelerated beryllium corrosion from celotex and water which may occur naturally when celotex dust comes into contact with moisture from the atmosphere

Modeling lung cancer risks in laboratory dogs exposed to inhaled plutonium

International Nuclear Information System (INIS)

Gilbert, E.S.; Park, J.F.; Buschbom, R.L.

1990-06-01

These analyses are based on data from a lifespan study of beagle dogs exposed to inhaled plutonium being conducted at Pacific Northwest Laboratory. An important goal of this study is to increase understanding of health risk resulting from this exposure, with particular attention to lung cancer risks. Data on humans exposed to plutonium are inadequate for achieving this goal

Project VALOR: Trajectories of Change in PTSD in Combat-Exposed Veterans

Science.gov (United States)

2015-10-01

Post - traumatic stress disorder ( PTSD ), military sexual trauma (MST), suicide, combat-exposed veterans, PTSD ...develop the first longitudinal registry of combat-exposed men and women with post - traumatic stress disorder ( PTSD ), 1649 participants from across the...Keane, T. M. (2012). Project VALOR: Design and methods of a longitudinal registry of post - traumatic stress disorder ( PTSD ) in

Affect Expression and Self-Regulation Capacities of Infants Exposed In Utero to Psychotropics

Directory of Open Access Journals (Sweden)

Pratibha N Reebye

2012-02-01

Full Text Available This study explored the affect expression and self-regulation capacities of eight month old infants exposed in utero to psychotropic medications. This is a continuation of our previous study conducted on the same cohort when infants were three months old. Psychotropics implicated are antidepressant medications: selective serotonin reuptake inhibitors (SSRI, and a benzodiazepine derivative anxiolytic (clonazepam. The three comparison groups were: control (n=23 (infants gestationally non-exposed to psychotropics, SSRI-alone (n=22 (infants exposed to SSRIs only and having mothers who had a primary diagnosis of depressive disorder without having comorbid anxiety disorder, and SSRI+ group (n=15 (infants gestationally exposed to SSRIs and Clonazepam and having mothers that had both clinical depression and anxiety disorder. Thirty-seven participants from the initial cohort were recruited. Using the Parent Child Early Relational Assessment Scale (PCERA, infants were assessed in a dyadic context during free play and a structured task. There were clear significant differences in psychotropic exposed and non-exposed dyads regarding infant negative affect management. Notable findings were that the SSRI+ group mothers showed significant associations with only one infant affect: i.e. infant negative affect. This group of mothers also showed significant associations with infant’s averting and avoiding behaviors. These associations were seen in both free play and structured task situations signifying probable established pattern. SSRI-alone group was similar to control mothers and showed variable associations with infant’s positive, negative and sober moods unlike SSRI+ group. There were no differences in infants’ capacity for self–regulation in psychotropic exposed and non-exposed groups. Increased awareness of these vulnerable subgroups (SSRI-alone and SSRI+ is needed, in order to safeguard these dyads through better support systems and improved

Exposed versus buried intramedullary implants for pediatric forearm fractures: a comparison of complications.

Science.gov (United States)

Kelly, Brian A; Miller, Patricia; Shore, Benjamin J; Waters, Peter M; Bae, Donald S

2014-12-01

The purpose of this study was to compare the rate of complications between buried and exposed intramedullary implants after fixation of pediatric forearm fractures. A retrospective comparative cohort study of 339 children treated with intramedullary fixation for displaced forearm fractures between 2004 and 2009 was performed. Implants were left exposed in 128 patients (37.8%) and buried beneath the skin in 208 patients (61.4%); 3 patients had buried and exposed hardware (0.9%). Data on demographics, injury, surgical technique, and complications were analyzed. The buried implant group was older (mean 10.3 vs. 8.5 y; P exposed implant group. The buried group had their implants removed later than the exposed group (median 3.5 vs. 1.2 mo; P exposed implants were successfully removed in the office. Complications were seen in 56 patients (16.5%). There were 16 patients (4.7%) with refracture and 12 patients (3.5%) with infection. The buried and exposed implant groups did not differ significantly with respect to refracture (3.1% vs. 7.0%; P = 0.20), infection (3.5% vs. 2.3%; P = 0.66), or overall complications (14.5% vs. 17.2%; P = 0.87). There was also no difference between groups with respect to loss of reduction, nondelayed or delayed union, loss of motion, hypertrophic granuloma, or tendon rupture. Buried implants were also associated with penetration through the skin (3.9%). Injury to the dominant arm and need for open reduction were significant predictors of complication (OR = 1.01; 95% CI, 1.001-1.012; P = 0.02 and OR = 0.51; 95% CI, 0.264-0.974; P = 0.04, respectively). There were no significant differences seen in number of infections, refractures, or overall complications based on whether implants were left exposed or buried beneath the skin after surgery. Level III, therapeutic.

Protection of man: the exposed individual

Energy Technology Data Exchange (ETDEWEB)

Bohnstedt, A.; Knebel, J.U. [Programme Nuclear Safety Research, Karlsruhe Institute of Technology, Herrmann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Breustedt, B. [Institute for Radiation Research, Karlsruhe Institute of Technology, Herrmann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

2010-07-01

Present methods for quantifying radiation exposure rely on a standardized reference man (75 kg) with defined average anatomical and physiological data. But individual person actually exposed differs from this idealized standard man. Therefore the focus of investigations at the Institute for Radiation Research (Institut fuer Strahlenforschung, ISF) which was founded at Karlsruhe Institute of Technology (Karlsruher Institut fuer Technologie, KIT) in 2009 is based on the vision to place the exposed individual with its anatomical and physiological particularities, under consideration of age, gender, body height, body shape and environment, in the centre of an individual-related quantification of the external and internal radiation exposure. Research work at the ISF is aiming at quantifying radiation exposure by improved determination of doses essentially caused by external radiation fields and the intake of radionuclides into the body. The three main topics of the institute are - external dosimetry (e.g. using a (voxel) model of the hand to simulate skin dose distribution); - internal dosimetry (e.g. body size related efficiency calibration of in-vivo counting equipment); - numerical methods/modeling (e.g. development of a mathematical/voxel-hybrid model of the human body). (authors)

The differences in phenolic content in rivers exposed and non-exposed to anthropogenic contamination.

Science.gov (United States)

Michałowicz, Jaromir; Bukowska, Bozena; Duda, Wirgiliusz

2008-03-01

The purpose of the work was to determine the differences in a kind, number and concentrations of phenol, chlorophenols, chlorocatechols chlorinated methoxyphenols (chloroguaiacols, chlorosyringols) and 3,4,5-trichloroveratrole in the drainage of the Dzierzazna river, the flow non-exposed to anthropogenic contamination and in the Ner river, the flow exposed to anthropogenic pollution. The samples of water were collected in the Dzierzazna river in the Swoboda locality, the inflow of the Dzierzazna river - the Ciosenka river and, also, in the spring situated in Ciosny Sady locality. Water of the Ner river was collected in points near Łódź, Konstantynów, Poddebice and Dabie towns. The compounds were condensed (adsorbed) and eluted with methylene chloride on octadecyl C18 layer in a Baker Separex system. The obtained eluent was separated using the method of gas chromatography and analysed using mass spectrometry technique. In samples collected from the drainage of the Dzierzazna river phenol, chlorophenols, guaiacol, trichloroguaiacol, tetrachloroguaiacol, trichlorosyringol and 3,4,5-trichloroveratole were determined. As no anthropogenic sources are situated within the drainage of the Dzierzazna river, we may suppose that most of the determined compounds are mainly of natural origin. No or trace concentrations of chlorinated methoxyphenols were noted in the water of the Ner river, but a higher number, and concentrations of chlorophenols and additionally chlorocatechols were determined in this flow. It is also apparent that changes in a number and concentrations of phenols in the water of the Ner river did not prove a seasonal character, which was typical of the Dzierzazna drainage waters.

Cigarette smoke-exposed saliva suppresses cellular and humoral immune responses in an animal model

International Nuclear Information System (INIS)

Jafarzadeh, A.; Bakhshi, H.; Rezayati, M.T.; Nemati, M.

2009-01-01

To evaluate the effects of cigarette smoke (CS)-exposed saliva on cellular and antibody responses in an animal model. The stimulatory and non-stimulatory saliva samples were collected from 10 healthy subjects and were then exposed to CS for 20 or 80 minutes. The CS-exposed saliva samples were administrated intraperitoneally (i.p) to male Balb/c mice. Then the delayed type hypersensitivity (DTH) and antibody responses to sheep red blood cell (SRBC) was assessed. Moreover, the total white blood cells (WBC) counts and the blood lymphocytes counts were determined. The mean of DTH responses of animal groups received 20 minutes or 80 minutes CS-exposed saliva samples was significantly lower than that observed in control group. Moreover, The mean titer of anti-SRBC antibody was significantly lower in animal groups who received 80 minutes CS-exposed stimulatory or non-stimulatory saliva as compared to control group (P<0.04 and P<0.002, respectively). The mean counts of blood lymphocytes in 80 minutes CS exposed-stimulatory saliva group was also significantly lower as compared to control group (P<0.05). These results show that the CS-exposed saliva samples have profound suppressive effects on both cellular and humoral immune response in a mouse animal model (JPMA 59:760; 2009). (author)

Cerebrospinal fluid cells and proteins in patients occupationally exposed to organic solvents

Energy Technology Data Exchange (ETDEWEB)

Juntunen, J; Taskinen, E; Luisto, M; Iivanainen, M; Nurminen, M

1982-06-01

Cerebrospinal fluid (CSF) cells and proteins were determined for 33 patients exposed to industrial organic solvents. A lymphoid reaction, i.e., a pathologically elevated number or percentage of enlarged lymphoid cells was observed in one-third of the patients, more often in patients with chronic intoxication (40%) than in those currently exposed to organic solvents (32%). An almost significant decrease of small lymphocytes in the CSF was observed among patients who had a past history of chronic solvent intoxication but no recent exposure. No cytological evidence of tissue destruction was found. Signs of slight blood--CSF barrier damage occurred in 5 (23%) of the currently exposed patients, but intrathecal IgG synthesis was not observed. Increased cellular activity in the CSF was also accentuated in principal component analysis. The results suggest slight nonspecific immunoactivation in the central nervous system of subjects exposed to organic solvents.

Differential cardiac effects in rats exposed to atmospheric ...

Science.gov (United States)

The results of this study demonstrate that atmospheric smog generated from both isoprene and toluene cause cardiac effects in rats. In addition, it appears that smog from toluene is more toxic in terms of cardiac arrhythmogenicity. Smog, which is a complex mixture of particulate matter and gaseous irritants (ozone, sulfur dioxide, reactive aldehydes), as well as components which react with sunlight to form secondary pollutants, has recently been linked to increased risk of adverse cardiac responses. The components, and therefore health effects, of atmospheric smog are determined by the fuel used to generate them. In this study we examined the difference between isoprene- and toluene-generated smog in causing cardiac effects in rats and hypothesized that both atmospheres would cause cardiac electrical and functional changes in rats. Male Wistar-Kyoto rats were exposed to either atmospheric smog generated by the USEPA’s mobile reaction chamber using either isoprene or toluene, or filtered air for four hours. One day later, rats were anesthetized and left ventricular functional responses to dobutamine were measured using a Millar probe and arrhythmia sensitivity to aconitine. Baseline left ventricular pressure (LVP) was lower in toluene-exposed animals but not isoprene when compared to air. Increases in LVP with increasing doses of dobutamine were impaired only in toluene-exposed rats. Both isoprene and toluene impaired the rate of ventri

Study of chromosome aberrations on the workers occupationally exposed to thorium and rare earth mixed dust

International Nuclear Information System (INIS)

Zhang Wei; Wang Chunyan; Lv Huiming; Zhang Cuilan; Hao Shuxia; Su Xu; Jia Kejun; Liu Yufei

2008-01-01

Objective: To study the effect of thorium and rare earth mixed dust on chromosome aberrations in the lymphocytes of occupational exposed workers. Methods: Analyses of unstable chromosome aberrations on 53 occupational exposed workers and 58 control workers were carried out by the conventional Giemsa staining method. Fluorescence in situ hybridization method was performed to analyze the chromosome stable aberrations on 10 occupational exposed workers and l0 control workers. Results: The frequencies of chromosomal aberration cells, dicentrics plus rings, total aberrations in exposed workers were significantly higher than those in controls. No significant difference was found in the frequency of acentric aberrations between exposed and non-exposed workers. No significant difference was found in the frequency of translocations between exposed and non-exposed workers. Conclusions: Chronically occupational exposure to thorium and rare earth mixed dust can increase the induction of unstable chromosome aberration, but the increase of stable chromosome aberrations (translocation) can not be observed. (authors)

Potassium ion influx measurements on cultured Chinese hamster cells exposed to 60-hertz electromagnetic fields

International Nuclear Information System (INIS)

Stevenson, A.P.; Tobey, R.A.

1985-01-01

Potassium ion influx was measured by monitoring 42 KCl uptake by Chinese hamster ovary (CHO) cells grown in suspension culture and exposed in the culture medium to 60-Hz electromagnetic fields up to 2.85 V/m. In the presence of the field CHO cells exhibited two components of uptake, the same as previously observed for those grown under normal conditions; both these components of influx were decreased when compared to sham-exposed cells. Although decreases were consistently observed in exposed cells when plotted as loge of uptake, the differences between the means of the calculated fluxes of exposed and sham-exposed cells were quite small (on the order of 4-7%). When standard deviations were calculated, there was no significant difference between these means; however, when time-paired uptake data were analyzed, the differences were found to be statistically significant. Cells exposed only to the magnetic field exhibited similar small decreases in influx rates when compared to sham-exposed cells, suggesting that the reduction in K+ uptake could be attributed to the magnetic field. Additionally, intracellular K+ levels were measured over a prolonged exposure period (96 h), and no apparent differences in intracellular K+ levels were observed between field-exposed and sham-exposed cultures. These results indicate that high-strength electric fields have a small effect on the rate of transport of potassium ions but no effect on long-term maintenance of intracellular K+

Micronuclei frequency in children exposed to environmental mutagens: a review

DEFF Research Database (Denmark)

Neri, Monica; Fucic, Aleksandra; Knudsen, Lisbeth E

2003-01-01

Cytogenetic monitoring has been traditionally used for the surveillance of populations exposed to genotoxic agents. In recent years sensitivity problems emerged in surveys of populations exposed to low levels of mutagens, and therefore alternative approaches have been explored. Biomonitoring....... The limited number of published papers indicates that the conduct of properly designed studies on the effect of environmental pollutants in children may be difficult. This review confirmed the usefulness of MN assay in biomonitoring studies conducted in children, revealing that in many circumstances...

Ethylene thiourea: thyroid function in two groups of exposed workers

Energy Technology Data Exchange (ETDEWEB)

Smith, D.M.

1984-08-01

Ethylene thiourea is manufactured at one factory in the United Kingdom and is mixed into masterbatch rubber at another. Clinical examinations and thyroid function tests were carried out over a period of three years on eight process workers and five mixers and on matched controls. The results show that the exposed mixers, but not exposed process workers, have significantly lower levels of total thyroxine (T4) than the controls. One mixer had an appreciably raised level of thyroid stimulation hormone (TSH).

Ethylene thiourea: thyroid function in two groups of exposed workers.

Science.gov (United States)

Smith, D M

1984-08-01

Ethylene thiourea is manufactured at one factory in the United Kingdom and is mixed into masterbatch rubber at another. Clinical examinations and thyroid function tests were carried out over a period of three years on eight process workers and five mixers and on matched controls. The results show that the exposed mixers, but not exposed process workers, have significantly lower levels of total thyroxine (T4) than the controls. One mixer had an appreciably raised level of thyroid stimulation hormone (TSH).

Incidence of brain tumours in rats exposed to an aerosol of 239PuO2

International Nuclear Information System (INIS)

Sanders, C.L.; Dagle, G.E.; Mahaffey, J.A.

1992-01-01

Incidence of brain tumours was investigated in 3390 female and male Wistar rats exposed to an aerosol of 239 PuO 2 , or as sham-exposed controls. Lung doses ranged from 0.05 to 22 Gy. In females, six brain tumours were found in 1058 control rats (incidence, 0.6%) and 24 brain tumours in 2134 rats exposed to Pu (incidence, 1.1%); the survival-adjusted level of significance was p = 0.29 for comparing control with exposed females. In males, two brain tumours were found in 60 control rats (incidence, 3.3%) and seven brain tumours in 138 rats exposed to Pu (incidence, 5.1%); the survival-adjusted level of significance was p = 0.33. Brain tumour incidence was about five times greater in male than in female rats (p = 0.0001), a highly significant sex difference in brain tumour incidence. Tumour types were distributed similarly among control and Pu-exposed groups of both sexes; most were astrocytomas. Mean lifespans for rats with brain tumours were not significantly different between control and Pu-exposed rats. (author)

Structural analysis of osseous rests exposed to heating

International Nuclear Information System (INIS)

Medina, C.; Tiesler, V.; Quintana, P.; Oliva, A.I.

2005-01-01

Heat exposed human remains present physical and chemical changes that, when analysed, may provide important indications about the type of heating they were exposed. This information, jointly with that of the archaeological context, allows us to know about the cultural practices of the past from a methodological perspective that actually, has not been explored sufficiently. The present investigation applies a series of structural parameters of bone in the evaluation of skeletal sample from the archaeological site of Calakmul, which exhibits signs of thermal exposure. Results on the Pre hispanic specimens are compared to those obtained from an experimental series of animal bone, which was submitted to different types of heat with the objective to contribute with new data on the forms of heating and their role in ancient Maya society. (Author)

Expose Mechanical Engineering Students to Biomechanics Topics

Science.gov (United States)

Shen, Hui

2011-01-01

To adapt the focus of engineering education to emerging new industries and technologies nationwide and in the local area, a biomechanics module has been developed and incorporated into a mechanical engineering technical elective course to expose mechanical engineering students at ONU (Ohio Northern University) to the biomedical engineering topics.…

Biomarkers of oxidative stress in electroplating workers exposed to hexavalent chromium.

Science.gov (United States)

Pan, Chih-Hong; Jeng, Hueiwang Anna; Lai, Ching-Huang

2018-01-01

This study evaluates levels of biomarkers of oxidative DNA damage and lipid peroxidation in 105 male workers at 16 electroplating companies who had been exposed to hexavalent chromium (Cr(VI)). The study participants were 230 non-smoking male workers, comprising 105 electroplating workers who had been exposed to chromium and 125 control subjects who performed office tasks. Personal air samples, spot urine samples, hair samples, fingernail samples and questionnaires were used to quantify exposure to Cr(VI), oxidative DNA damage, lipid peroxidation, and environmental pollutants. Both the geometric mean personal concentrations of Cr(VI) of the Cr-exposed workers and the total Cr concentrations in the air to which they were exposed significantly exceeded those for the control subjects. The geometric mean concentrations of Cr in urine, hair and fingernails, and the urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG), and malondialdehyde (MDA) levels in the Cr(VI) exposed workers exceeded those in the control subjects. Daily cumulative Cr(VI) exposure and urinary Cr were significantly correlated with urinary 8-OHdG levels following adjustments for covariates. A ten-fold increase in urinary Cr level was associated with a 1.73-fold increase in urinary 8-OHdG level. Daily cumulative Cr(VI) exposure and urinary Cr level were significantly correlated with urinary MDA level following adjustments for covariates. A ten-fold increase in urinary Cr was associated with a 1.45-fold increase in urinary MDA. Exposure to Cr(VI) increased oxidative DNA injury and the oxidative deterioration of lipids in electroplating workers.

Metabolic profile and genotoxicity in obese rats exposed to cigarette smoke.

Science.gov (United States)

Damasceno, Debora C; Sinzato, Yuri K; Bueno, Aline; Dallaqua, Bruna; Lima, Paula H; Calderon, Iracema M P; Rudge, Marilza V C; Campos, Kleber E

2013-08-01

Experimental studies have shown that exposure to cigarette smoke has negative effects on lipid metabolism and oxidative stress status. Cigarette smoke exposure in nonpregnant and pregnant rats causes significant genotoxicity (DNA damage). However, no previous studies have directly evaluated the effects of obesity or the association between obesity and cigarette smoke exposure on genotoxicity. Therefore, the aim of the present investigation was to evaluate DNA damage levels, oxidative stress status and lipid profiles in obese Wistar rats exposed to cigarette smoke. Female rats subcutaneously (s.c.) received a monosodium glutamate solution or vehicle (control) during the neonatal period to induce obesity. The rats were randomly distributed into three experimental groups: control, obese exposed to filtered air, and obese exposed to tobacco cigarette smoke. After a 2-month exposure period, the rats were anesthetized and killed to obtain blood samples for genotoxicity, lipid profile, and oxidative stress status analyses. The obese rats exposed to tobacco cigarette smoke presented higher DNA damage, triglycerides, total cholesterol, free fatty acids, VLDL-c, HDL-c, and LDL-c levels compared to control and obese rats exposed to filtered air. Both obese groups showed reduced SOD activity. These results showed that cigarette smoke enhanced the effects of obesity. In conclusion, the association between obesity and cigarette smoke exposure exacerbated the genotoxicity, negatively impacted the biochemical profile and antioxidant defenses and caused early glucose intolerance. Thus, the changes caused by cigarette smoke exposure can trigger the earlier onset of metabolic disorders associated with obesity, such as diabetes and metabolic syndrome. Copyright © 2012 The Obesity Society.

In vitro cell-mediated immunity studies of plutonium-exposed beagle dogs

International Nuclear Information System (INIS)

Morris, J.E.; Graham, T.; Park, J.F.

1980-01-01

Mitogen-induced activation was measured in spleen and mesenteric lymph node cell preparations from dogs exposed to a single inhalation exposure of plutonium oxide ( 238 Pu or 239 Pu). Reduced stimulation indices of splenic lymphocytes from exposed animals suggest that a reduction in lymphocyte function has occurred in this tissue. No apparent reduction in mitogen stimulation indices was observed in mesenteric lymph node cultures

Laboratory results of some biological measures in workers exposed to lead

Energy Technology Data Exchange (ETDEWEB)

Secchi, G.C.; Alessio, L.

1974-12-01

Erthrocyte ALA-dehydratase (ALAD) activity and blood lead values were studied in different groups of subjects not occupationally exposed to lead and compared with values for exposed workers. The results lead to the conclusion that measurement of ALAD activity is more useful in evaluating possible exposure of general population groups to minimal quantities of lead than in the surveillance of workers in the lead industries.

Cytogenetic monitoring of hospital workers exposed to low-level ionizing radiation

International Nuclear Information System (INIS)

Bigatti, P.; Lamberti, L.; Ardito, G.; Armellino, F.

1988-01-01

In the present study the cytogenetic effects in hospital workers exposed to low-level radiation were evaluated. Samples of peripheral blood were collected from 63 subjects working in radiodiagnostics and from 30 subjects, working in the same hospitals, who were used as controls. A higher number of cells with chromosome-type aberrations (CA) was observed in the exposed workers vs. the controls and the difference was statistically significant (p<0.05). No correlation was, on the contrary, found between CA and years of exposure. A significant difference was observed in the incidence of cells with CA between smokers and non-smokers, but in the control group only. In contrast, in the workers exposed to ionizing radiation, the frequency of cells with CA was very similar in smokers and non-smokers. 13 refs.; 4 tabs

Fatty acid composition of fish species with different feeding habits from an Arctic Lake.

Science.gov (United States)

Gladyshev, M I; Sushchik, N N; Glushchenko, L A; Zadelenov, V A; Rudchenko, A E; Dgebuadze, Y Y

2017-05-01

We compared the composition and content of fatty acids (FAs) in fish with different feeding habits (sardine (least) cisco Coregonus sardinella, goggle-eyed charr (pucheglazka) form of Salvelinus alpinus complex, humpback whitefish Coregonus pidschian, broad whitefish Coregonus nasus, boganid charr Salvelinus boganidae, and northern pike Esox lucius from an Arctic Lake. Feeding habits of the studied fish (planktivore, benthivore, or piscivore) significantly affected the composition of biomarker fatty acids and the ratio of stable isotopes of carbon and nitrogen in their biomass. The hypothesis on a higher content of eicosapentaenoic and docosahexaenoic acids in the fish of higher trophic level (piscivores) when compared within the same taxonomic group (order Salmoniformes) was confirmed.

Exposing the Mathematical Wizard: Approximating Trigonometric Functions

Science.gov (United States)

Gordon, Sheldon P.

2011-01-01

For almost all students, what happens when they push buttons on their calculators is essentially magic, and the techniques used are seemingly pure wizardry. In this article, the author draws back the curtain to expose some of the mathematics behind computational wizardry and introduces some fundamental ideas that are accessible to precalculus…

Psychophysical Evaluation of Achromatic and Chromatic Vision of Workers Chronically Exposed to Organic Solvents

International Nuclear Information System (INIS)

Lacerda, E.M.D.B.; Lima, M.G.; Silveira, L.C.D.S.; Rodrigues, A.R.; Teixeira, C.E.C.; De Lima, L.J.B.; Silveira, L.C.D.S.; Ventura, D.F.; Ventura, D.F.

2012-01-01

The purpose of this paper was to evaluate achromatic and chromatic vision of workers chronically exposed to organic solvents through psychophysical methods. Thirty-one gas station workers (31.5 ± 8.4 years old) were evaluated. Psychophysical tests were achromatic tests (Snellen chart, spatial and temporal contrast sensitivity, and visual perimetry) and chromatic tests (Ishihara's test, color discrimination ellipses, and Farnsworth-Munsell 100 hue test FM100). Spatial contrast sensitivities of exposed workers were lower than the control at spatial frequencies of 20 and 30 cpd whilst the temporal contrast sensitivity was preserved. Visual field losses were found in 10-30 degrees of eccentricity in the solvent exposed workers. The exposed workers group had higher error values of FM100 and wider color discrimination ellipses area compared to the controls. Workers occupationally exposed to organic solvents had abnormal visual functions, mainly color vision losses and visual field constriction

Urine mutagenicity of steel workers exposed to coke oven emissions

Energy Technology Data Exchange (ETDEWEB)

De Meo, M.P.; Dumenil, G.; Botta, A.H.; Laget, M.; Zabaloueff, V.; Mathias, A.

1987-03-01

Urine mutagenicity of 19 individuals was investigated at a steel mill. All the subjects worked on the coal processing unit. Urine samples were collected at the end of a working day. Urine samples of two exposed workers were collected at the end of two periods of rest and two periods of working. Mutagens were extracted on XAD-2 resin and tested by the Salmonella microsomal assay and the SOS spot test. Mutagenic potencies of exposed smokers and exposed non-smokers were 8.62 +/- 6.56 and 1.1 +/- 0.48 revertants/mg creatinine respectively with Salmonella typhimurium strain TA98 + S9. Both values were significantly higher than those of unexposed smokers and non-smokers (5.07 +/- 3.33 and 0.47 +/- 0.72 revertants/mg creatinine respectively). The urinary mutagenic potency of the two exposed individuals increased at the end of periods of working (15.97 +/- 2.57 revertants/mg creatinine) and decreased at the end of periods of rest (12.31 +/- 2.45 revertants/mg creatinine). Urinary mutagens were detected with S. typhimurium strain TA100 + S9 to a lesser extent. No direct-acting mutagens were detected by the SOS spot test. Atmospheric benzo(a)pyrene (BaP) were also measured by h.p.l.c. on the coke battery. BaP concentrations ranged between 0.01 and 0.6 microgram/m3 air at the different working sites. Biological monitoring with short-term tests is discussed.

Expression of advanced glycation end-products on sun-exposed and non-exposed cutaneous sites during the ageing process in humans.

Science.gov (United States)

Crisan, Maria; Taulescu, Marian; Crisan, Diana; Cosgarea, Rodica; Parvu, Alina; Cãtoi, Cornel; Drugan, Tudor

2013-01-01

The glycation process is involved in both the intrinsic (individual, genetic) and extrinsic (ultraviolet light, polution and lifestyle) aging processes, and can be quantified at the epidermal or dermal level by histological, immunohistochemical (IHC), or imagistic methods. Our study is focused on a histological and immunohistological comparison of sun-protected regions versus sun-exposed regions from different age groups of skin phototype III subjects, related to the aging process. Skin samples collected from non-protected and UV protected regions of four experimental groups with different ages, were studied using histology and IHC methods for AGE-CML [N(epsilon)-(carboxymethyl)lysine]. A semi-quantitative assessment of the CML expression in the microvascular endothelium and dermal fibroblasts was performed. The Pearson one-way ANOVA was used to compare data between the groups. In the dermis of sun-exposed skin, the number and the intensity of CML positive cells in both fibroblasts and endothelial cells (p<0.05) was higher compared to sun-protected skin, and was significantly increased in older patients. The sun-exposed areas had a more than 10% higher AGE-CML score than the protected areas. No statistically significant correlation was observed between the histological score and the IHC expression of CML. We concluded that in healthy integument, the accumulation of final glycation products increases with age and is amplified by ultraviolet exposure. The study provides new knowledge on differences of AGE-CML between age groups and protected and unprotected areas and emphasizes that endothelium and perivascular area are most affected, justifying combined topical and systemic therapies.

Expression of advanced glycation end-products on sun-exposed and non-exposed cutaneous sites during the ageing process in humans.

Directory of Open Access Journals (Sweden)

Maria Crisan

Full Text Available The glycation process is involved in both the intrinsic (individual, genetic and extrinsic (ultraviolet light, polution and lifestyle aging processes, and can be quantified at the epidermal or dermal level by histological, immunohistochemical (IHC, or imagistic methods. Our study is focused on a histological and immunohistological comparison of sun-protected regions versus sun-exposed regions from different age groups of skin phototype III subjects, related to the aging process. Skin samples collected from non-protected and UV protected regions of four experimental groups with different ages, were studied using histology and IHC methods for AGE-CML [N(epsilon-(carboxymethyllysine]. A semi-quantitative assessment of the CML expression in the microvascular endothelium and dermal fibroblasts was performed. The Pearson one-way ANOVA was used to compare data between the groups. In the dermis of sun-exposed skin, the number and the intensity of CML positive cells in both fibroblasts and endothelial cells (p<0.05 was higher compared to sun-protected skin, and was significantly increased in older patients. The sun-exposed areas had a more than 10% higher AGE-CML score than the protected areas. No statistically significant correlation was observed between the histological score and the IHC expression of CML. We concluded that in healthy integument, the accumulation of final glycation products increases with age and is amplified by ultraviolet exposure. The study provides new knowledge on differences of AGE-CML between age groups and protected and unprotected areas and emphasizes that endothelium and perivascular area are most affected, justifying combined topical and systemic therapies.

Assessing color vision loss among solvent-exposed workers.

Science.gov (United States)

Mergler, D; Blain, L

1987-01-01

Acquired color vision loss has been associated with exposure to organic solvents in the workplace. However, not all tests of chromatic discrimination loss are designed to detect acquired, as opposed to congenital, loss. The Lanthony D-15 desaturated panel (D-15-d), a simple 15 cap color arrangement test, designed to identify mild acquired dyschromatopsia, can be administered rapidly in the field, under standard conditions. The objective of the present study was to evaluate the D-15-d among 23 solvent-exposed workers of a paint manufacturing plant, by comparing the results obtained with the D-15-d to those obtained with the Farnsworth-Munsell 100 Hue (FM-100), a highly sensitive measure of color vision loss. The D-15-d revealed a significantly higher prevalence of dyschromatopsia among the ten highly exposed workers (80%) as compared to the 13 moderately exposed workers (30.8%); FM-100 results revealed one false positive. All dyschromatopic workers presented blue-yellow loss; the FM-100 detected eight complex patterns, while the D-15-d identified 5. Comparison of D-15-d and FM-100 scores were highly correlated (corr. coeff. 0.87; p less than 0.001). Multiple regression analyses showed both scores to be significantly related to age and exposure level. The findings of this study indicate that the D-15-d is an adequate instrument for field study batteries. However, the FM-100 should be used for more detailed assessment.

Care of HIV-exposed and HIV-infected neonates

African Journals Online (AJOL)

However, further reduction in MTCT may be possible if newborns at high risk of acquiring HIV ... infants of breastfeeding mothers with newly diagnosed HIV infection, dual NVP/ .... birth HIV DNA PCR testing for HIV-exposed low birth weight.

Blood Pressure of Jordanian Workers Chronically Exposed to Noise in Industrial Plants

Directory of Open Access Journals (Sweden)

Saed Nserat

2017-10-01

Full Text Available Background: Occupational studies investigating the association between blood pressure and noise exposure are almost lacking in the Eastern Mediterranean Region countries. Objective: To determine the association between occupational exposure to high level of noise and blood pressure among a group of workers in Jordan. Methods: All workers who had been exposing to noise for at least 3 years in 3 plants in Madaba governorate in Jordan were included in this cross-sectional study. A structured questionnaire was used to collect data. The occupational noise level was measured with a portable calibrated sound meter. Results: We studied 191 male workers, of whom 145 (75.9% were exposed to a noise level higher than the permissible limit of 85 dBA. The mean systolic blood pressure (SBP and diastolic blood pressure (DBP and the prevalence of hypertension were significantly higher among those exposed to higher noise level. In multivariate analysis, workers exposed to high level of noise had a significantly higher odds of hypertension compared to those exposed to noise level lower than the permissible limit (OR 4.7, 95% CI 1.6 to 13.8. The odds of hypertension increased by 17% (95% CI 10% to 30% for each dB increase in noise intensity. Conclusion: Exposure to high level of noise is associated with elevated blood pressure.

Preference for safflower oil in rats exposed to a cold environment under free-feeding conditions.

Science.gov (United States)

Saitoh, Masaji; Ishii, Toshiaki; Takewaki, Tadashi; Nishimura, Masakazu

2005-07-01

There are several benefits to a high-fat diet for animals exposed to cold, including improved tolerance to severe cold conditions and increased survival rates in cold environments. It is therefore of interest to examine whether animals exposed to cold will selectively consume lipids. We examined the intake of safflower oil (SO) by rats exposed to cold (4 +/- 2 degrees C) under a feeding condition in which the rats were given free access to SO. Rats exposed to cold consumed more SO than those housed at 25 +/- 2 degrees C. This finding suggests that rats prefer SO in a cold environment. There was no significant difference in the ratio of calories of SO ingested to that of matter (standard laboratory chow plus SO) ingested between rats exposed to cold and those at 25 +/- 2 degrees C. The high SO intake also affected cold tolerance and metabolite kinetics in the rats. Factors that affected the SO intake of rats exposed to cold are also discussed.

Toxicity of lunar dust assessed in inhalation-exposed rats.

Science.gov (United States)

Lam, Chiu-wing; Scully, Robert R; Zhang, Ye; Renne, Roger A; Hunter, Robert L; McCluskey, Richard A; Chen, Bean T; Castranova, Vincent; Driscoll, Kevin E; Gardner, Donald E; McClellan, Roger O; Cooper, Bonnie L; McKay, David S; Marshall, Linda; James, John T

2013-10-01

Humans will again set foot on the moon. The moon is covered by a layer of fine dust, which can pose a respiratory hazard. We investigated the pulmonary toxicity of lunar dust in rats exposed to 0, 2.1, 6.8, 20.8 and 60.6 mg/m(3) of respirable-size lunar dust for 4 weeks (6 h/day, 5 days/week); the aerosols in the nose-only exposure chambers were generated from a jet-mill ground preparation of a lunar soil collected during the Apollo 14 mission. After 4 weeks of exposure to air or lunar dust, groups of five rats were euthanized 1 day, 1 week, 4 weeks or 13 weeks after the last exposure for assessment of pulmonary toxicity. Biomarkers of toxicity assessed in bronchoalveolar fluids showed concentration-dependent changes; biomarkers that showed treatment effects were total cell and neutrophil counts, total protein concentrations and cellular enzymes (lactate dehydrogenase, glutamyl transferase and aspartate transaminase). No statistically significant differences in these biomarkers were detected between rats exposed to air and those exposed to the two low concentrations of lunar dust. Dose-dependent histopathology, including inflammation, septal thickening, fibrosis and granulomas, in the lung was observed at the two higher exposure concentrations. No lesions were detected in rats exposed to ≤6.8 mg/m(3). This 4-week exposure study in rats showed that 6.8 mg/m(3) was the highest no-observable-adverse-effect level (NOAEL). These results will be useful for assessing the health risk to humans of exposure to lunar dust, establishing human exposure limits and guiding the design of dust mitigation systems in lunar landers or habitats.

Hospital morphine preparation for abstinence syndrome in newborns exposed to buprenorphine or methadone.

Science.gov (United States)

Colombini, Nathalie; Elias, Riad; Busuttil, Muriel; Dubuc, Myriam; Einaudi, Marie-Ange; Bues-Charbit, Martine

2008-06-01

This study was undertaken to evaluate the adequacy of a hospital formulated oral morphine preparation for management of neonatal abstinence syndrome (NAS) and to compare clinical features in infants exposed to methadone or buprenorphine in utero. Between October 1998 and October 2004 all infants born to mothers treated with buprenorphine or methadone during pregnancy were enrolled into this prospective study. Morphine hydrochloride solution (0.2 mg/ml) was prepared without preservatives under a flow laminar air box (class 100). Morphine solution: quantitative and qualitative HPLC analysis and microbiological study at regular intervals during storage at 4 degrees C for 6 months. Maternal characteristics: age, opiate dose during pregnancy. Neonatal characteristics: gestational age at delivery, birth weight, Lipsitz scores. Morphine dose: daily morphine dose, maximum morphine dose, duration of NAS, and duration of treatment required to achieve stable Lipsitz scores below 4. Kruskal-Wallis test for comparison of median values. Microbiological and HPLC analysis showed that the morphine preparation remained stable for 6 months at 4 degrees C. Nine methadone-exposed infants and 13 buprenorphine-exposed infants were included in the study. All infants presented NAS requiring treatment with the morphine solution. Lipsitz scores at birth were significantly different in the methadone and buprenorphine groups (P methadone group required significantly higher doses of morphine preparation than the buprenorphine group during the first 38 days of treatment (P methadone-exposed infants (range 6-24 h) and within 48 h after birth in buprenorphine-exposed infants (range 24-168 h). Due to the possibility of delayed onset of NAS up to 7 days, infants born to mothers treated with buprenorphine should be kept in the hospital for an appropriate surveillance period. Treatment time was significantly longer (45 vs. 28 days) and the mean morphine doses were higher (1.7 fold) in methadone-exposed

Interaction of Al with O2 exposed Mo2BC

International Nuclear Information System (INIS)

Bolvardi, Hamid; Music, Denis; Schneider, Jochen M.

2015-01-01

Highlights: • Al adheres to many surfaces. • Solid–solid interactions challenging for real (oxidized) surfaces. • Dissociative O 2 adsorption on Mo 2 BC(0 4 0). • Al nonamer is disrupted on oxidized Mo 2 BC(0 4 0). • Adhesion of a residual Al on the native oxide. - Abstract: A Mo 2 BC(0 4 0) surface was exposed to O 2 . The gas interaction was investigated using ab initio molecular dynamics and X-ray photoelectron spectroscopy (XPS) of air exposed surfaces. The calculations suggest that the most dominating physical mechanism is dissociative O 2 adsorption whereby Mo−O, O−Mo−O and Mo 2 −C−O bond formation is observed. To validate these results, Mo 2 BC thin films were synthesized utilizing high power pulsed magnetron sputtering and air exposed surfaces were probed by XPS. MoO 2 and MoO 3 bond formation is observed and is consistent with here obtained ab initio data. Additionally, the interfacial interactions of O 2 exposed Mo 2 BC(0 4 0) surface with an Al nonamer is studied with ab initio molecular dynamics to describe on the atomic scale the interaction between this surface and Al to mimic the interface present during cold forming processes of Al based alloys. The Al nonamer was disrupted and Al forms chemical bonds with oxygen contained in the O 2 exposed Mo 2 BC(0 4 0) surface. Based on the comparison of here calculated adsorption energy with literature data, Al−Al bonds are shown to be significantly weaker than the Al−O bonds formed across the interface. Hence, Al−Al bond rupture is expected for a mechanically loaded interface. Therefore the adhesion of a residual Al on the native oxide layer is predicted. This is consistent with experimental observations. The data presented here may also be relevant for other oxygen containing surfaces in a contact with Al or Al based alloys for example during forming operations

Effect of lead exposure on the immune response of some occupationally exposed individuals

International Nuclear Information System (INIS)

Mishra, Kamla Prasad; Singh, Vijay Kumar; Rani, Reena; Yadav, Virendra Singh; Chandran, Vinod; Srivastava, Satya Prakash; Seth, Prahlad Kishore

2003-01-01

Lead is a ubiquitous pollutant in the industrial environment, which poses serious threats to human health. In the past 20 years increasing attention has been paid to the effects of lead exposure on health. This toxic metal alters the immune response of animals as well as humans. To study the immunological effects of occupational exposure to lead, we examined lymphocyte proliferation, natural killer (NK) cell cytotoxicity and interferon-γ production with peripheral blood mononuclear cells (PBMCs) of individuals occupationally exposed to lead. We selected three different groups of individuals exposed to lead: three-wheeler drivers (30), battery workers (34) and silver jewelery makers (20); and unexposed healthy volunteers (30) as control for comparison. Our results indicate that though lymphocyte proliferation to phytohaemagglutinin (PHA) is inhibited in lead exposed individuals as compared with unexposed volunteers, there is no correlation between inhibition of lymphocyte proliferation and blood lead level. NK cell cytotoxicity remains unaffected in individuals exposed to lead as compared with controls. On the other hand, we observed that interferon-γ (IFN-γ) was significantly elevated in T cell mitogen, PHA, stimulated PBMCs culture supernatant of lead exposed individuals. We found significant positive correlation between blood lead levels and IFN-γ produced in culture supernatant on stimulation with PHA. In brief, this study demonstrates that lead can affect the immune response of the occupationally exposed individuals such as three-wheeler drivers, battery reconditioning workers and silver jewelery makers

High chromosomal instability in workers occupationally exposed to solvents and paint removers.

Science.gov (United States)

Villalba-Campos, Mónica; Chuaire-Noack, Lilian; Sánchez-Corredor, Magda Carolina; Rondón-Lagos, Milena

2016-01-01

Painters are exposed to an extensive variety of harmful substances like aromatic hydrocarbons used as solvents and paint removers, some of which have shown clastogenic activity. These substances constitute a complex mixture of chemicals which contain well-known genotoxicants, such as Benzene, Toluene and Xylene. Thus, chronic occupational exposure to such substances may be considered to possess genotoxic risk. In Colombia the information available around the genotoxic damage (Chromosomal and DNA damage) in car paint shop workers is limited and the knowledge of this damage could contribute not only to a better understanding of the carcinogenic effect of this kind of substances but also could be used as biomarkers of occupational exposure to genotoxic agents. In this study, the genotoxic effect of aromatic hydrocarbons was assessed in peripheral blood lymphocytes of 24 workers occupationally exposed and 24 unexposed donors, by using Cytogenetic analysis and comet assay. A high frequency of Chromosomal alterations was found in the exposed group in comparison with those observed in the unexposed group. Among the total of CAs observed in the exposed group, fragilities were most frequently found (100 %), followed by chromosomal breaks (58 %), structural (41.2 %) and numerical chromosomal alterations (21 %). Numerical chromosomal alterations, fragilities and chromosomal breaks showed significant differences between exposed and unexposed groups. Among the fragilities, fra(9)(q12) was the most frequently observed. DNA damage index was also significantly higher in the exposed group compared to the unexposed group (p car paint shops workers and are also indicative of high chromosomal instability. The high frequency of both Chromosomal Alterations and DNA Damage Index observed in this study indicates an urgent need of intervention not only to prevent the increased risk of developing cancer but also to the application of strict health control and motivation to the use of

Cytogenetic monitoring of personnel occupationally exposed to microwave radiation of GEM radar

International Nuclear Information System (INIS)

Garaj-Vrhovac, Vera; Gajski, Goran; Brumen, Vlatka

2008-01-01

In the present study we analyzed and followed-up on the DNA damaging effects of microwave radiation of GEM radar equipment within microwave field of 10 μW/cm 2 to 10 mW/cm 2 in personnel occupationally exposed to frequency range of 1.5 GHz to 10.9 GHz. The single cell gel electrophoresis (SCGE)/comet assay as a tool for the bio monitoring of individuals accidentally, environmentally or occupationally exposed to physical or chemical agents was used to evaluate possible genotoxic effect on peripheral human blood lymphocytes. The comet assay is a method that allows efficient determination of single strand breaks (SSB) and double-strand breaks (DSB), as well as alkali-labile sites in the DNA of single cells. The comet assay was carried out under alkaline conditions. We measured the baseline comet assay effect in whole blood samples. Parameter of the comet assay was studied in workers occupationally exposed to microwave radiation of GEM radar and in corresponding unexposed control subjects. It was found that in the subjects who were occupationally exposed to microwave radiation, the levels of DNA damage increased compare to control group and showed interindividual variations. As a measure of DNA damage tail length was used, calculated from the centre of the head and presented in micrometers (μm). Mean value of exposed group was 13.54±1.44 as opposed to control mean value that was 13.15±1.39. Differences between mean tail lengths were statistically significant (P<0.05, ANOVA). The results of this study indicate that individuals occupationally exposed to microwave frequency of GEM radar equipment may experience an increased genotoxic risk, emphasizing the importance of individual bio monitoring, limiting exposure and radiation safety programs. (author)

A synthetic medical and sociological study on twins exposed by atomic bomb, 8

International Nuclear Information System (INIS)

Satow, Yukio; Watanabe, Shoji; Kyo, Taiichi

1984-01-01

The relationship between immunoglobulin (IgG, IgA, IgM) levels and the exposure status was examined in 13 enzygotic twin pairs who had been exposed to atomic bomb under the same or different conditions and who had no disease showing changes in immunoglobulin levels. The difference in immunoglobulin levels tended to be smaller between the twins exposed under the same conditions and to be larger between the twins exposed under the different conditions. This should be further studied because there were some exceptions in this study. (Namekawa, K.)

Preventive medical programmes to personnel exposed to ionizing radiation

International Nuclear Information System (INIS)

Estrada F, E.

1996-01-01

The increasing use of ionizing radiation in the medical field as well as in industry and research grants has special importance to the security aspects related to the individual as well as his surroundings, reason for which the implementation of effective Occupational Radiation Protection Programmes constitutes a priority. Presently, in Guatemala, an Occupational Medicine Programme, directed to the Radiosanitary watch over of occupationally exposed personnel does not exist. It is the goal in this project to organize and establish such programme, based on protective and training actions focused toward the employee as the main entity, his specific activities and his work surroundings. Medical watch over together with Radiation Protection will permit the reduction of the occurrence probability of accidents or incidents, as well as the limitation of stochastic effects to the undermost values. The application scope of the present project is, in the first place, directed to the occupationally exposed personnel of the Direcci[n General de Energ[a Nuclear, as regulatory entity of these activities, and afterwards, its application in the different institutions which work with ionizing radiations. All the previously exposed is based on the Nuclear Legislation prevailing in Guatemala as well as the recommendations of international organizations. (author)

Brain damage among the prenatally exposed

International Nuclear Information System (INIS)

Otake, Masanori; Schull, W.J.; Yoshimaru, Hiroshi.

1991-01-01

Significant effects on the developing brain of exposure to ionizing radiation are seen among those individuals exposed in the 8th through the 25th week after fertilization. These effects, particularly in the most sensitive period, 8-15 weeks after fertilization, manifest themselves as an increased frequency of severe mental retardation (SMR), a diminution in IQ score and in school performance, and an increase in the occurrence of seizures. Of 30 SMR cases, 18 (60%) had small heads. About 10% of the individuals with small head sizes observed among the in utero clinical sample were mentally retarded. When all of the cases of mental retardation are included in the analysis, a linear dose-response model fits the data adequately and no evidence of a threshold emerges; however, if the two probable nonradiation-related cases of Down's syndrome are excluded from the 19 SMR cases exposed 8-15 weeks after fertilization, the evidence of a threshold is stronger. The 95% lower bound of the threshold based on the new dosimetry system appears to be in the range of 0.12-0.23 Gy. In the 16-25 week period, the 95% lower bound of the threshold is 0.21 Gy both with and without inclusion of two probable nonradiation-related retarded cases. In a regression analysis of IQ scores and school performance data, a greater linearity is suggested with the new dosimetry (DS86) than with the old (T65DR), but the mean IQ score and the mean school performance of those exposed in utero to doses under 0.10 Gy are similar, and not statistically different from the means in the control group. The risk ratios for unprovoked seizures, following exposure during the 8th through the 15th week after fertilization, are 4.4 (90% confidence interval: 0.5-40.9) after 0.10-0.49 Gy and 24.9 (4.1-191.6) after 0.50 Gy or more when the mentally retarded are included and 4.4 (0.5-40.9) and 14.5 (0.4-199.6), respectively, when they are excluded. (author)

Effects of Vitamin C on Kidney and Bone of Rats Exposed to Low ...

African Journals Online (AJOL)

ABSTRACT: In this study, the effect of vitamin C on cadmium-induced toxicity was investigated. Wister rats were exposed to ... and muscles of cadmium exposed rats (1.0- ..... Fauci, A.S., Braunwald, K., Isselbacher, K.J., Wilson,. J.D., Martin ...

Studies of workers exposed to low doses of external radiation

International Nuclear Information System (INIS)

Gilbert, E.S.

1991-04-01

Currently, several epidemiologic studies of workers who have been exposed occupationally to low levels of radiation are being conducted, and include studies of workers in the United States, Great Britain, and Canada involved in the production of both defense materials and nuclear power. This paper focuses on studies that evaluate the possible adverse effects resulting from external exposure to radiation. The radiation risk estimates that have been used to establish radiation protection standards for workers and others have been obtained mainly from studies of persons exposed at high doses and dose rates. However, questions remain with regard to the extrapolation process that has been necessary for estimating low-level radiation risks. Occupational studies provide a direct assessment of risk based on data on persons exposed at the actual levels of interest. If current risk estimates are correct, these studies have very little chance of detecting risk, but can still be used to provide useful upper limits on risks. The studies are also adequate to detect serious underestimation of risks. 36 refs., 3 figs., 3 tabs

Developmental toxicity in flounder embryos exposed to crude oils derived from different geographical regions.

Science.gov (United States)

Jung, Jee-Hyun; Lee, Eun-Hee; Choi, Kwang-Min; Yim, Un Hyuk; Ha, Sung Yong; An, Joon Geon; Kim, Moonkoo

2017-06-01

Crude oils from distinct geographical regions have distinct chemical compositions, and, as a result, their toxicity may be different. However, developmental toxicity of crude oils derived from different geographical regions has not been extensively characterized. In this study, flounder embryos were separately exposed to effluents contaminated by three crude oils including: Basrah Light (BLO), Pyrenees (PCO), and Sakhalin Vityaz (SVO), in addition to a processed fuel oil (MFO-380), to measure developmental toxicity and for gene expressions. Each oil possessed a distinct chemical composition. Edema defect was highest in embryos exposed to PCO and MFO-380 that both have a greater fraction of three-ring PAHs (33% and 22%, respectively) compared to BLO and SVO. Observed caudal fin defects were higher in embryos exposed to SVO and MFO-380, which are both dominated by naphthalenes (81% and 52%, respectively). CYP1A gene expressions were also highest in embryos exposed to SVO and MFO-380. Higher incidence of cardiotoxicity and lower nkx 2.5 expression were detected in embryos exposed to PCO. Unique gene expression profiles were observed in embryos exposed to crude oils with distinct compositions. This study demonstrates that crude oils of different geographical origins with different compositional characteristics induce developmental toxicity to different degrees. Copyright © 2017 Elsevier Inc. All rights reserved.

Dental health of young children prenatally exposed to buprenorphine. A concern of child neglect?

Science.gov (United States)

Kivistö, K; Alapulli, H; Tupola, S; Alaluusua, S; Kivitie-Kallio, S

2014-06-01

To study the oral health and dental neglect of prenatally buprenorphine-exposed 3-year-old children. The study consisted of 51 children who as newborns tested positive for buprenorphine in a urine screen. The control group comprised 68 children previously unexposed to narcotics. The dentist examined the children and interviewed their guardians. Buprenorphine-exposed children exhibited significantly more early childhood caries than did the control group. Caries indices, the number of decayed, missing and filled teeth or tooth surfaces and decayed teeth were greater in the buprenorphine-exposed children than the control children (p = 0.004, p = 0.004, p = 0.001, respectively). In the buprenorphine group, more children showed visible plaque (p = 0.003) and fewer children were caries-free (p = 0.009) than in the control group. The control children's teeth were also brushed more often than the buprenorphine-exposed children's teeth (p = 0.001) and the parents were more involved in their children's tooth brushing than were those in the buprenorphine-exposed group (p = 0.035). More caries and dental neglect were found in buprenorphine-exposed children than in controls. These findings highlight the importance of routine dental appointments, caries screening and preventive care for children in substance-abusing families.

Analysis of plutonium-239 in occupationally exposed personnel

International Nuclear Information System (INIS)

Hernandez M, H.

2017-10-01

Apart from radiometric techniques, several mass spectrometry (Ms) techniques can be used to evaluate the incorporation of plutonium-239 in occupationally exposed personnel, among which we can consider mass spectrometry with inductively coupled plasma source (Icp-Ms); mass spectrometry with accelerators (AMS); thermal ionization mass spectrometry (TIMS) and secondary ion mass spectrometry (Sims). In this work we evaluated analytical methods to measure isotopes of plutonium-239 in urine samples from occupationally exposed personnel, using alpha spectroscopy (As), magnetic sector mass spectrometry with inductively coupled plasma source (Icp-SFMS) and AMS. The samples were collected during 24 h were acidified with HNO 3 at 5% in v/v. The processes used in the preparation of the samples were: a) co-precipitation, b) acid digestion, c) radiochemical separation and d) electro deposition. The results obtained in terms of minimum detectable activity of plutonium-239 were 0.1 μBq (∼ 0.4 fg per sample), 5.1 μBq (∼ 2 fg per sample), 30.1 μBq (∼ 13 fg per sample) and 0.1 μBq (∼ 51 fg per sample) for AMS, Aridus-Icp-SFMS, Icp, SFMS and As, respectively. On the other hand, samples previously analyzed by As were re-evaluated by Aridus-Icp-SFMS and AMS. The results show that extraction with 60 ml of 5% HNO 3 at 60 degrees Celsius and for 2.5 h is enough to extract 90% of Pu electrodeposited on the planchette. In conclusion, AMS is an ultra-sensitive technique for determining isotope ratios of Pu, especially when is desired to validate a method to measure plutonium-239. Additionally, Icp-SFMS is a rapid analysis technique and can be used as a screening technique in situations of radiological incidents or accidents with Pu in the occupationally exposed personnel. Regarding alpha spectroscopy has been considered as the technique of excellence in the routine analysis to measure plutonium-239 in occupationally exposed personnel, due to the low cost. Finally, Icp-SFMS and AMS

Cytogenetic study of in utero exposed individuals, 2

Energy Technology Data Exchange (ETDEWEB)

Itoh, Masahiro; Honda, Takeo

1986-11-01

In 20 persons exposed in uterus to atomic radiation, chromosomes in the peripheral lymphocytes were examined using G-band differential staining and conventional Giemsa staining techniques. The subjects were divided into Group A of the mothers receiving 17 - 535 rad and Group B of the mothers receiving 0 rad. Chromosome aberrations were observed in 72 (5%) of 1,463 cells in Group A and in 19 (1%) of 1503 cells in Group B. Most of the chromosome aberrations were stable type involving translocation, inversion, and deletion. In one person whose mother was exposed to 453 rad, structural chromosome aberrations were observed in 53 (38%) of 141 cells. Furthermore, 11 cells had two kinds of clones. This finding may provide clues for elucidating the promotion of cloning of cells with stable type structural chromosome aberrations due to in uterus exposure to high doses of atomic radiation. (Namekawa, K.).

Cytogenetic study of in utero exposed individuals, 2

International Nuclear Information System (INIS)

Itoh, Masahiro; Honda, Takeo

1986-01-01

In 20 persons exposed in uterus to atomic radiation, chromosomes in the peripheral lymphocytes were examined using G-band differential staining and conventional Giemsa staining techniques. The subjects were divided into Group A of the mothers receiving 17 - 535 rad and Group B of the mothers receiving 0 rad. Chromosome aberrations were observed in 72 (5 %) of 1,463 cells in Group A and in 19 (1 %) of 1503 cells in Group B. Most of the chromosome aberrations were stable type involving translocation, inversion, and deletion. In one person whose mother was exposed to 453 rad, structural chromosome aberrations were observed in 53 (38 %) of 141 cells. Furthermore, 11 cells had two kinds of clones. This finding may provide clues for elucidating the promotion of cloning of cells with stable type structural chromosome aberrations due to in uterus exposure to high doses of atomic radiation. (Namekawa, K.)

Late and latent effects of atomic bomb on chromosomes in the exposed population

Energy Technology Data Exchange (ETDEWEB)

Tanaka, R; Kamada, N [Hiroshima Univ. (Japan). Research Inst. for Nuclear Medicine and Biology

1976-09-01

Cytogenetic changes of exposed individuals, and the diseases and cytogenetic changes of the F/sub 1/ were discussed. The subjects exposed within 0.5 km. from the hypocenter revealed chromosomal aberration of the bone marrow in 83 per cent and those within 0.5 to 1.0 km. from the hypocenter revealed it in 47 per cent. The aberration was mostly the stable type, and was frequent in deletion, balanced-type translocation, unbalanced-type translocation, and inversion, in the order named. The number of abnormal clone varied with year. The chromosomes of the lymphocytes in the peripheral blood also showed high rate of stable type aberration, and the chromosomes were also aberrant in the fibroblasts of the keloid lesion. However, there were no abnormalities in the spermatogonium. Thirty seven subjects of F/sub 1/ group included 13 subjects whose father had been exposed, 19 subjects whose mother had been exposed, and 5 subjects whose both parents had been exposed. The diseases seen in the F/sub 1/ subjects were hematonosis in 28 subjects, autoimmune diseases in 5 subjects, and hypertension and lymphadenitis in 4 cases. Acute myelogenic leukemia (AML) showed normal chromosomes in all the 3 cases, the acute lymphatic leukemia (ALL), showed abnormal clones in 2 of 3 cases. Chronic myelogenic leukemia (CML) revealed abnormal chromosomes in all the 3 cases. The cytogenetic changes of abnormal clone in the F/sub 1/ of non-exposed were 60 per cent in AML, 57 per cent, in ALL and 100 per cent in CML.

Chest pain in rubber chemical workers exposed to carbon disulphide and methaemoglobin formers

Energy Technology Data Exchange (ETDEWEB)

Oliver, L.C.; Weber, R.P.

1984-08-01

A cross sectional prevalence study of chest pain in 94 rubber chemical workers exposed to carbon disulfide (CS2) and methemoglobin forming aromatic amines was carried out. The purpose of the study was to determine whether the prevalence of chest pain or coronary heart disease (CHD), or both, in exposed individuals exceeded that of a group of non-exposed individuals from the same plant. Cardiovascular, smoking, and occupational histories were obtained. Blood pressure, height, weight, serum cholesterol, and fasting blood glucose were measured. Resting electrocardiograms (ECGs) were obtained on all study participants, as were exercise stress tests on selected exposed individuals. Matching eliminated important known risk factors for coronary artery disease. Both chest pain and angina were significantly related to exposure, controlling for age and cigarette smoking. This association was not dependent on duration of exposure as defined by 10 or more years of employment in the department of interest. CHD as defined by angina, a history of myocardial infarction, or a coronary ECG or a combination of these occurred more frequently among exposed workers. The number of abnormal ECGs in the exposed group was twice that in the control group, but the difference was not statistically significant. Age rather than exposure appeared to be the important variable associated with raised blood pressure. Neither biological measures of exposure nor ECGs showed an acute effect of workplace exposures on the myocardium. Possible additive or multiplicative effects of individual chemical agents could not be evaluated. Appropriate modification of medical surveillance of rubber chemical workers with exposure to CS2 and aromatic amines is warranted.

Late and latent effects of atomic bomb on chromosomes in the exposed population

International Nuclear Information System (INIS)

Tanaka, Ryuji; Kamada, Nanao

1976-01-01

Cytogenetic changes of exposed individuals, and the diseases and cytogenetic changes of the F 1 were discussed. The subjects exposed within 0.5 km. from the hypocenter revealed chromosomal aberration of the bone marrow in 83 per cent and those within 0.5 to 1.0 km. from the hypocenter revealed it in 47 per cent. The aberration was mostly the stable type, and was frequent in deletion, balanced-type translocation, unbalanced-type translocation, and inversion, in the order named. The number of abnormal clone varied with year. The chromosomes of the lymphocytes in the peripheral blood also showed high rate of stable type aberration, and the chromosomes were also aberrant in the fibroblasts of the keloid lesion. However, there were no abnormalities in the spermatogonium. Thirty seven subjects of F 1 group included 13 subjects whose father had been exposed, 19 subjects whose mother had been exposed, and 5 subjects whose both parents had been exposed. The diseases seen in the F 1 subjects were hematonosis in 28 subjects, autoimmune diseases in 5 subjects, and hypertension and lymphadenitis in 4 cases. Acute myelogenic leukemia (AML) showed normal chromosomes in all the 3 cases, the acute lymphatic leukemia (ALL), showed abnormal clones in 2 of 3 cases. Chronic myelogenic leukemia (CML) revealed abnormal chromosomes in all the 3 cases. The cytogenetic changes of abnormal clone in the F 1 of non-exposed were 60 per cent in AML, 57 per cent, in ALL and 100 per cent in CML. (Mukohata, S.)

Natural history of disease in atomic bomb exposed twins in Hiroshima

International Nuclear Information System (INIS)

Satow, Yukio; Ohmae, Kiyokazu; Okamoto, Naomasa; Abe, Tsutomu; Watanabe, Shoji

1982-01-01

The subjects of this study are mainly pairs of monozygotic twins, one of whom was exposed to the atomic bomb and the other not exposed, and the natural history of the diseases of these twins was analyzed to find out genetic and environmental factors of the diseases and some biological effect of the atomic bomb exposure or other. In this study, 13 pairs of monozygotic and 5 pairs of dizygotic twins and other 34 cases of non-twins were examined by means of heart and lung X-ray films and electrocardiograms. The results suggest that most of the monozygotic twins show the similar findings of chest X-ray films, though their electrocardiograms have a tendency to deviate to the left in the QRS axis. These findings will not be enough to clear up the relation between the atomic bomb exposed and the abnormal electrocardiograms. (author)

Development Enamel Defects in Children Prenatally Exposed to Anti-Epileptic Drugs

DEFF Research Database (Denmark)

Jacobsen, Pernille Endrup; Henriksen, Tine Brink; Haubek, Dorte

2013-01-01

Objective Some anti-epileptic drugs (AED) have well-known teratogenic effects. The aim of the present study was to elucidate the effect of prenatal exposure to AED and the risk of enamel defects in the primary and permanent dentition. Methods A total of 38 exposed and 129 non-exposed children, 6......–10 years of age, were recruited from the Aarhus Birth Cohort and the Department of Neurology, Viborg Regional Hospital, Denmark. Medication during pregnancy was confirmed by the Danish Prescription Database. All children had their teeth examined and outcomes in terms of enamel opacities and enamel...... hypoplasia were recorded. Results Children prenatally exposed to AED have an increased prevalence of enamel hypoplasia (11% vs. 4%, odds ratio (OR) = 3.6 [95% confidence interval (CI): 0.9 to 15.4]), diffuse opacities (18% vs. 7%, OR = 3.0; [95% CI: 1.0 to 8.7, p3) white opacities (18...

Effects of glutamine pretreatment on learning and memory in heat-exposed rats

Institute of Scientific and Technical Information of China (English)

Shenghao Zhao; Lei Wang; Qin Wang; Siyi Wang; Chundi Deng; Xianfei Xie; Youe Yan; Hui Wang

2008-01-01

BACKGROUND: Glutamine (Gln) pretreatment can protect neural cells from injuries due to heat, ischemia, hypoxia, endotoxemia, and inflammatory factors.OBJECTIVE: To observe the effects of Gln pretreatment on learning and memory, survival time, and rectal temperature in heat-exposed rats.DESIGN, TIME AND SETTING: The present randomized grouping, neurobehavioral experiment was performed at the Laboratory of Department of Pharmacology, Basic School of Medicine, Wuhan University between March and September 2007.MATERIALS: Twenty-four healthy, Wistar rats were included in this study. SPX-160B biochemistry incubator (Shanghai Experimental Equipment Co., Ltd., China), probe electronic thermometer (11000 type, Maikepai Science and Technology Co., Ltd., China), Y-type maze box used in conjunction with MG-2 maze stimulator (Zhangjiagang Biomedical Instrument Factory, China), L-Gin (Batch No. 061218, 5 g/bottle, prepared into 10% aqueous solution, Amresco Company, USA) were used.METHODS: Twenty-four rats were randomly and evenly divided into 3 groups: heat-exposed, Gln low-lose, and Gln high-dose. Following learning and memory testing with the Y-maze, rats in the heat-exposed group were subjected to heat injury (40.5-41.5℃) in a biochemistry incubator. Rectal temperature was measured every 5 minutes. Thirty-five minutes after heat exposure, rats were removed and placed in the Y-type maze to test learning and memory again. Subsequently, the rats were returned to the same environment of thermal stimulation until they died. Rat survival time was recorded. Subsequent to learning and memory testing, rats in the Gln low-dose and high-dose groups received an i.p. injection of Gln (0.4 g/kg and 0.8 g/kg, respectively), and were exposed to heat injury. The remaining experimental procedures remained the same as for the heat-exposed group.MAIN OUTCOME MEASURES: Rat learning and memory, rectal temperature, and survival time in heat exposure environment.RESULTS: (1) In the Y

Personality and psychopathological profiles in individuals exposed to mobbing.

Science.gov (United States)

Girardi, Paolo; Monaco, Edoardo; Prestigiacomo, Claudio; Talamo, Alessandra; Ruberto, Amedeo; Tatarelli, Roberto

2007-01-01

Increasingly, mental health and medical professionals have been asked to assess claims of psychological harm arising from harassment at the workplace, or "mobbing." This study assessed the personality and psychopathological profiles of 146 individuals exposed to mobbing using validity, clinical, and content scales of the Minnesota Multiphasic Personality Inventory 2. Profiles and factor analyses were obtained. Two major dimensions emerged among those exposed to mobbing: (a) depressed mood, difficulty in making decisions, change-related anguish, and passive-aggressive traits (b) somatic symptoms, and need for attention and affection. This cross-sectional pilot study provides evidence that personality profiles of mobbing victims and psychological damage resulting from mobbing may be evaluated using standardized assessments, though a longitudinal study is needed to delineate cause-and-effect relationships.

Fracture behaviour of the 14Cr ODS steel exposed to helium and liquid lead

Science.gov (United States)

Hojna, Anna; Di Gabriele, Fosca; Hadraba, Hynek; Husak, Roman; Kubena, Ivo; Rozumova, Lucia; Bublikova, Petra; Kalivodova, Jana; Matejicek, Jiri

2017-07-01

This work describes the fracture behaviour of the 14Cr ODS steel produced by mechanical alloying process, after high temperature exposures. Small specimens were exposed to helium gas in a furnace at 720 °C for 500 h. Another set of specimens was exposed to flowing liquid lead in the COLONRI II loop at 650 °C for 1000 h. All specimens were tested for the impact and tensile behaviour. The impact test results are compared to other sets of specimens in the as received state and after isothermal annealing at 650 °C for 1000 h. The impact curves of the exposed materials showed positive shifts on the transition temperature. While the upper shelf value did not change in the Pb exposed ODS steel, it significantly increased in the He exposed one. The differences are discussed in terms of surface and subsurface microscopy observation. The embrittlement can be explained as the effect of a slight change in the grain boundary and size distribution combined with the depletion of sub-surface region from alloying elements forming oxide scale on the surface.

Effect of Nanoparticles Exposure on Fractional Exhaled Nitric Oxide (FENO in Workers Exposed to Nanomaterials

Directory of Open Access Journals (Sweden)

Wei-Te Wu

2014-01-01

Full Text Available Fractional exhaled nitric oxide (FENO measurement is a useful diagnostic test of airway inflammation. However, there have been few studies of FENO in workers exposed to nanomaterials. The purpose of this study was to examine the effect of nanoparticle (NP exposure on FENO and to assess whether the FENO is increased in workers exposed to nanomaterials (NM. In this study, both exposed workers and non-exposed controls were recruited from NM handling plants in Taiwan. A total of 437 subjects (exposed group = 241, non-exposed group = 196 completed the FENO and spirometric measurements from 2009–2011. The authors used a control-banding (CB matrix to categorize the risk level of each participant. In a multivariate linear regression analysis, this study found a significant association between risk level 2 of NP exposure and FENO. Furthermore, asthma, allergic rhinitis, peak expiratory flow rate (PEFR, and NF-κB were also significantly associated with FENO. When the multivariate logistic regression model was adjusted for confounders, nano-TiO2 in all of the NM exposed categories had a significantly increased risk in FENO > 35 ppb. This study found associations between the risk level of NP exposure and FENO (particularly noteworthy for Nano-TiO2. Monitoring FENO in the lung could open up a window into the role nitric oxide (NO may play in pathogenesis.

Life satisfaction and school performance of children exposed to classic and cyber peer bullying.

Science.gov (United States)

Bilić, Vesna; Flander, Gordana Buljan; Rafajac, Branko

2014-03-01

This paper analyses the relationship between the exposure of school children to various forms of peer bullying (classic/cyber) and their life satisfaction in the domain of school, family, friends and school performance. The sample included 562 children from rural and urban areas of Croatia who were attending the seventh and the eighth grade of primary school. Results show that children were more often exposed to classic forms of peer bullying, especially verbal, and then physical bullying. On the other hand, cyber bullying most often comprises harassment in forums, blogs, chats or social networks, then on the web, by e-mail and mobile phone. Almost half of the examinees knew the identity of the bully, while a minority believes that bullies are the same ones who also physically abuse them at school. We found that children exposed to all forms of both classic and cyber bullying, unlike their peers who do not have such experience, show less satisfaction with friends, while those exposed to physical and cyber bullying show dissatisfaction with their family, too. However no statistically significant difference was found in their satisfaction with school. Children exposed to physical bullying showed poorer school performance, poorer achievement in Croatian and math, while children exposed to verbal and cyber bullying and children who were not exposed to such forms of bullying showed no differences in their school achievement.

90 days bioassay in sprague-dawley rats exposed to 20KHz magnetic field

Energy Technology Data Exchange (ETDEWEB)

Kim, Sung-Ho [College of Veterinary Medicine, Chonnam National Univ. Kwangju (Korea, Republic of); Song, Ji-Eun; Lee, Yun-Sil [Korea Cancer Center Hospital, Seoul (Korea, Republic of); Pack, Jeong-Ki [ETRI, Daejon (Korea, Republic of); Yoo, Done-SIk [College of Engineering, Daejon (Korea, Republic of)

2002-07-01

Sprague Dawley rats (20 rats/group [10 males, 10 females] in sham and magnetic field exposed groups) were exposed in carrousel irradiator to an 20 KHz magnetic field for 8 hrs/day, 5 days/week, for 90 days. Urine analysis (pH, SG, protein, ketone body, RBC, WBC, glucose, bilirubin, and urobilinogen), blood analysis (WBC, RBC, HGB; henoglubin concentration, HCT; hematocrit, MCV; mean corpuscular volume, MCH; mean corpuscular hemoglobin, MCHC; mean corpuscular hemoglobin concentration, and PLT; platelet or thrombocyte count), blood biochemistry (total protein, blood urea nitrogen, creatinine, glucose, total bilirubin, total cholesterol, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase), histopathological analysis for organs such as liver, kidney, testis, ovary, spleen, brain, heart, and lung were performed. When compared to the sham control rats, there were no significant differences in above analysis of magnetic field exposed rats. From the results, there were no significant differences between control and exposed fetus.

Species-specific sensitivity to selenium-induced impairment of cortisol secretion in adrenocortical cells of rainbow trout (Oncorhynchus mykiss) and brook trout (Salvelinus fontinalis)

International Nuclear Information System (INIS)

Miller, L.L.; Hontela, A.

2011-01-01

Species differences in physiological and biochemical attributes exist even among closely related species and may underlie species-specific sensitivity to toxicants. Rainbow trout (RT) are more sensitive than brook trout (BT) to the teratogenic effects of selenium (Se), but it is not known whether all tissues exhibit this pattern of vulnerability. In this study, primary cultures of RT and BT adrenocortical cells were exposed to selenite (Na 2 SO 3 ) and selenomethionine (Se-Met) to compare cell viability and ACTH-stimulated cortisol secretion in the two fish species. Cortisol, the primary stress hormone in fish, facilitates maintenance of homeostasis when fish are exposed to stressors, including toxicants. Cell viability was not affected by Se, but selenite impaired cortisol secretion, while Se-Met did not (RT and BT EC 50 > 2000 mg/L). RT cells were more sensitive (EC 50 = 8.7 mg/L) to selenite than BT cells (EC 50 = 90.4 mg/L). To identify the targets where Se disrupts cortisol synthesis, selenite-impaired RT and BT cells were stimulated with ACTH, dbcAMP, OH-cholesterol, and pregnenolone. Selenite acted at different steps in the cortisol biosynthesis pathway in RT and BT cells, confirming a species-specific toxicity mechanism. To test the hypothesis that oxidative stress mediates Se-induced toxicity, selenite-impaired RT cells were exposed to NAC, BSO and antioxidants (DETCA, ATA, Vit A, and Vit E). Inhibition of SOD by DETCA enhanced selenite-induced cortisol impairment, indicating that oxidative stress plays a role in Se toxicity; however, modifying GSH content of the cells did not have an effect. The results of this study, with two closely related salmonids, provided additional evidence for species-specific differences in sensitivity to Se which should be considered when setting thresholds and water quality guidelines. - Research Highlights: → We investigated species-specific sensitivity to Se in trout adrenocortical cells. → Selenite, not Se-Met, disrupts

Disturbances of perinatal carbohydrate metabolism in rats exposed to methylmercury in utero

Energy Technology Data Exchange (ETDEWEB)

Snell, K; Ashby, S L; Barton, S J

1977-12-01

Pregnant rats were given a single subcutaneous injection of methylmercuric chloride (at 4 or 8 mg/kg) on the ninth day of gestation. Fetal (2 days prenatal), newborn and postnatal (6 days post partum) animals from the methylmercury-treated mothers were investigated with respect to parameters of carbohydrate metabolism. In the absence of any physical abnormalities, fetal rats exposed to methylmercury in utero showed diminished concentrations of plasma glucose and liver glycogen concentrations and a lower hepatic glucose-6-phosphatase activity compared to control animals. Newborn rats from the methylmercury-treated mothers showed an impairment in glycogen mobilization in the first hours of extra-uterine life which was accompanied by a severe and protracted hypoglycemic response. Postnatal rats exposed to methylmercury in utero exhibited higher liver glycogen concentration and decreased body weights compared to control rats. The results point to a derangement of perinatal carbohydrate metabolism in the offspring of pregnant rats exposed briefly to low doses of methylmercury during gestation (''metabolic teratogenesis''). The postnatal hypoglycemic episode in exposed rats may contribute to the pathogenesis of the neurological disturbances revealed by these animals in later life.

Identification of Surface Exposed Elementary Body Antigens of ...

African Journals Online (AJOL)

This study sought to identify the surface exposed antigenic components of Cowdria ruminantium elementary body (EB) by biotin labeling, determine effect of reducing and non-reducing conditions and heat on the mobility of these antigens and their reactivity to antibodies from immunized animals by Western blotting.

English exposed common mistakes made by Chinese speakers

CERN Document Server

Hart, Steve

2017-01-01

Having analysed the most common English errors made in over 600 academic papers written by Chinese undergraduates, postgraduates, and researchers, Steve Hart has written an essential, practical guide specifically for the native Chinese speaker on how to write good academic English. English Exposed: Common Mistakes Made by Chinese Speakers is divided into three main sections. The first section examines errors made with verbs, nouns, prepositions, and other grammatical classes of words. The second section focuses on problems of word choice. In addition to helping the reader find the right word, it provides instruction for selecting the right style too. The third section covers a variety of other areas essential for the academic writer, such as using punctuation, adding appropriate references, referring to tables and figures, and selecting among various English date and time phrases. Using English Exposed will allow a writer to produce material where content and ideas-not language mistakes-speak the loudest.

Image restorations constrained by a multiply exposed picture

International Nuclear Information System (INIS)

Breedlove, J.R. Jr.; Kruger, R.P.; Trussell, H.J.; Hunt, B.R.

1977-01-01

There are a number of possible industrial and scientific applications of nanosecond cineradiographs. While the technology exists to produce closely spaced pulses of x rays for this application, the quality of the time-resolved radiographs is severely limited. The limitations arise from the necessity of using a fluorescent screen to convert the transmitted x rays to light and then using electro-optical imaging systems to gate and to record the images with conventional high-speed cameras. It has been proposed that in addition to the time-resolved images, a conventional multiply-exposed radiograph be obtained. Simulations are used to demonstrate that the additional information supplied by the multiply-exposed radiograph can be used to improve the quality of digital image restorations of the time-resolved pictures over what could be achieved with the degraded images alone. Because of the need for image registration and rubber sheet transformations, this problem is one which can best be solved on a digital, as opposed to an optical, computer

Chemical effects and their consequences for individuals occupationally exposed to ionizing radiation

International Nuclear Information System (INIS)

Salvador, C.; Kahl, G.G.; Kühn, P.; Zottis, A.D.; Flôr, R.C.

2017-01-01

By legal determination, workers exposed to ionizing radiation should use individual dosimeters in the most exposed region of the body, designed to estimate the effective dose, as well as radiation protective clothing to minimize occupational exposures. Regarding dosimetry, in most cases it is perceived that the monthly values of exposure are within the limits of normality, however, even being below the limit can not rule out the possibility of damage that the low dose of ionizing radiation can cause. The objective of this article is to highlight the main chemical effects caused by exposure to ionizing radiation, especially biochemical damage in DNA, chromosomal aberrations and the correlation with the exposure of occupationally exposed individuals, as well as individuals from the public. A bibliographic search was carried out in indexed databases from February to April 2017 with the following descriptors: Radiation Ionizing, DNA Damage and Occupational Exposure. In the 'Science Direct' database were found 1205 articles, in the 'Scopus' 19 articles, in the 'Web of Science' 83 articles, in the 'PubMed' 22 articles and in the 'VHL' 60 articles related to the theme. It was concluded that exposure to ionizing radiation can affect the DNA molecule despite its repair mechanisms, which may result in genotoxicity. It has been reported a correlation between occupationally exposed individuals and chromosomal aberrations, demonstrating that even low doses of ionizing radiation can compromise the genetic material integrity of exposed workers, leading to the need for a periodic cytogenetic study for this group of workers

Monitoring of genotoxic effects in lymphocytes of people exposed to pesticides

International Nuclear Information System (INIS)

Panek, A.; Marcos, R.; Cebulska-Wasilewska, A.

2002-01-01

The aim of this study was to assess the potential genotoxic risk of occupational exposure to pesticides. The DNA damage and the repair capacities of lymphocytes, in four groups of the people of various countries were assessed by the use of single cell gel electrophoresis (SCGE) also known as the Comet assay. The results from the analysis performed in the Spanish group are presented in this paper. Statistical analysis of the results shows a slightly higher level of the DNA damage in the untreated lymphocytes of donors from the group exposed to pesticides; however, only for donors below 30 years old are these differences significant (p<0.05). Although, comparison of the efficiency of the UV-C induced dimmers excision process did not indicate differences between exposed and referent groups, though lymphocytes for donors exposed to pesticides have shown a statistically lower repair rate (p<0.01) than lymphocytes from the unexposed group. (author)

A study of aluminium-exposed fish using a scanning proton microprobe

Energy Technology Data Exchange (ETDEWEB)

Cholewa, M; Legge, G L.F. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Eeckhaoudt, S; Van Grieken, R [Universitaire Instelling Antwerpen, Antwerp (Belgium)

1994-12-31

A major problem has arisen in Europe with the depopulation of fresh water fish in lakes and streams collecting acid rain. The sensitivity to acidification is species specific and appears to be associated with metal levels. The Scanning Proton Microprobe (SPMP) at the Micro Analytical Research Centre of the University of Melbourne was used to study the subcellular distribution of aluminium and other elements in the gills of fish exposed to acidified water with elevated Al-levels. Experiments were performed on thin sections taken from fish exposed to media with different pH and aluminium concentration. Aluminium was found on the surface of the gill lamellae, but also inside the tissue. Bulk analysis of the gills showed much higher concentrations in the aluminium-exposed fish, compared to the control ones, but no information regarding the actual accumulation sites can be inferred. Extensive study of damage done to the sample by intense proton beams during elemental analysis was performed with scanning transmission ion microscopy. 3 refs., 3 figs.

A study of aluminium-exposed fish using a scanning proton microprobe

Energy Technology Data Exchange (ETDEWEB)

Cholewa, M.; Legge, G.L.F. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Eeckhaoudt, S.; Van Grieken, R. [Universitaire Instelling Antwerpen, Antwerp (Belgium)

1993-12-31

A major problem has arisen in Europe with the depopulation of fresh water fish in lakes and streams collecting acid rain. The sensitivity to acidification is species specific and appears to be associated with metal levels. The Scanning Proton Microprobe (SPMP) at the Micro Analytical Research Centre of the University of Melbourne was used to study the subcellular distribution of aluminium and other elements in the gills of fish exposed to acidified water with elevated Al-levels. Experiments were performed on thin sections taken from fish exposed to media with different pH and aluminium concentration. Aluminium was found on the surface of the gill lamellae, but also inside the tissue. Bulk analysis of the gills showed much higher concentrations in the aluminium-exposed fish, compared to the control ones, but no information regarding the actual accumulation sites can be inferred. Extensive study of damage done to the sample by intense proton beams during elemental analysis was performed with scanning transmission ion microscopy. 3 refs., 3 figs.

A study of aluminium-exposed fish using a scanning proton microprobe

International Nuclear Information System (INIS)

Cholewa, M.; Legge, G.L.F.

1993-01-01

A major problem has arisen in Europe with the depopulation of fresh water fish in lakes and streams collecting acid rain. The sensitivity to acidification is species specific and appears to be associated with metal levels. The Scanning Proton Microprobe (SPMP) at the Micro Analytical Research Centre of the University of Melbourne was used to study the subcellular distribution of aluminium and other elements in the gills of fish exposed to acidified water with elevated Al-levels. Experiments were performed on thin sections taken from fish exposed to media with different pH and aluminium concentration. Aluminium was found on the surface of the gill lamellae, but also inside the tissue. Bulk analysis of the gills showed much higher concentrations in the aluminium-exposed fish, compared to the control ones, but no information regarding the actual accumulation sites can be inferred. Extensive study of damage done to the sample by intense proton beams during elemental analysis was performed with scanning transmission ion microscopy. 3 refs., 3 figs

Artificial stone dust-induced functional and inflammatory abnormalities in exposed workers monitored quantitatively by biometrics.

Science.gov (United States)

Ophir, Noa; Shai, Amir Bar; Alkalay, Yifat; Israeli, Shani; Korenstein, Rafi; Kramer, Mordechai R; Fireman, Elizabeth

2016-01-01

The manufacture of kitchen and bath countertops in Israel is based mainly on artificial stone that contains 93% silica as natural quartz, and ∼3500 workers are involved in cutting and processing it. Artificial stone produces high concentrations of silica dust. Exposure to crystalline silica may cause silicosis, an irreversible lung disease. Our aim was to screen exposed workers by quantitative biometric monitoring of functional and inflammatory parameters. 68 exposed artificial stone workers were compared to 48 nonexposed individuals (controls). Exposed workers filled in questionnaires, and all participants underwent pulmonary function tests and induced sputum analyses. Silica was quantitated by a Niton XL3 X-ray fluorescence spectrometer. Pulmonary function test results of exposed workers were significantly lower and induced sputa showed significantly higher neutrophilic inflammation compared to controls; both processes were slowed down by the use of protective measures in the workplace. Particle size distribution in induced sputum samples of exposed workers was similar to that of artificial stone dust, which contained aluminium, zirconium and titanium in addition to silica. In conclusion, the quantitation of biometric parameters is useful for monitoring workers exposed to artificial stone in order to avoid deterioration over time.

Immunomodulatory effects in workers exposed to naturally occurring asbestos fibers.

Science.gov (United States)

Ledda, Caterina; Costa, Chiara; Matera, Serena; Puglisi, Beatrice; Costanzo, Valentina; Bracci, Massimo; Fenga, Concettina; Rapisarda, Venerando; Loreto, Carla

2017-05-01

Natural asbestiform fibers are defined 'naturally occurring asbestos' (NOA) and refer to the mineral as a natural component of soils or rocks. The release of NOA fibers into the air from rocks or soils by routine human activities or natural weathering processes represents a risk for human beings. Fluoro-edenite (FE) is a NOA fiber detected in the benmoreitic lava in the area of Biancavilla, South-west slope of Mt. Etna. The aim of the present study was to investigate FE immunotoxicity pathways in a group of 38 occupationally exposed construction workers, in order to find any biological markers of its effect. Subjects underwent respiratory function tests and HRCT total chest scanning. Serum IL-1β, IL-6, IL-8 and TNF-α were measured. The presence of PPs was significantly greater in subjects exposed than in the control (25 vs. 2). In subjects exposed to FE, IL-1β and TNF-α values were significantly higher than the controls. The previously observed increase of IL-1β and IL-18 showed a probable involvement of the proteic complex defined inflammosome by FE fibers.

Antioxidant status of neonates exposed in utero to tobacco smoke.

Science.gov (United States)

Fayol, L; Gulian, J M; Dalmasso, C; Calaf, R; Simeoni, U; Millet, V

2005-01-01

To investigate the influence of maternal smoke exposure on neonatal and maternal antioxidant status, 39 mothers who were active smokers, 14 mothers exposed to environmental tobacco smoke (ETS), 17 controls, and their newborns were included in a prospective, controlled study. Plasma total antioxidant capacity, measured as total radical-trapping antioxidant parameter (TRAP) and ferric reducing antioxidant power (FRAP), and concentrations of specific antioxidants were measured in cord and in maternal blood. A similar, significant increase in ceruloplasmin concentration was observed in neonates born to actively smoking mothers and in those born to ETS exposed mothers. Uric acid and TRAP concentrations were significantly increased in ETS-exposed newborns and their mothers, compared to newborns and mothers from the active smoking and no-exposure groups with a trend towards increased uric acid, TRAP and FRAP concentrations being observed in the active smokers group. Neonatal and maternal antioxidant concentrations correlated significantly, except for ceruloplasmin. Cord blood vitamin A, E and C concentrations were unaffected by smoke exposure. These results show that maternal active smoking as well as ETS exposure significantly affect neonatal and maternal antioxidant status. Copyright (c) 2005 S. Karger AG, Basel

Clinical, cytogenetic and toxicological studies in rural workers exposed to pesticides in Botucatu, São Paulo, Brazil

Directory of Open Access Journals (Sweden)

Salete Marcia Bréga

1998-01-01

Full Text Available Pesticides can cause gene mutations and chromosomal aberrations in exposed individuals. We have investigated 24 workers exposed to pesticides. Clinical examinations and cytogenetic and toxicological tests were performed. Ten non-exposed individuals were used as controls. Toxicological dosages of copper, zinc and manganese (metals found in some pesticides, hepatic enzyme dosage (GOT, GPT, AR and acetylcholinesterase activity were performed in 16 workers and 8 controls. In the exposed workers, the most relevant clinical symptoms were poor digestion with fullness sensation after meals, irritated eyes, headache and fasciculations. The exposed group showed significantly lower manganese dosage and acetylcholinesterase activity, and significantly higher levels of alkaline phosphatase. Cytogenetic studies showed significantly higher chromosomal aberrations in the exposed group compared to the control group. Although the workers used protection against the pesticide's fog, the results revealed that the workers were contaminated with the pesticides. Therefore, the cytogenetic, toxicological studies with clinical examination are necessary for monitoring workers who are exposed to pesticides in any situation.

Transcriptional changes in oysters Crassostrea brasiliana exposed to phenanthrene at different salinities

International Nuclear Information System (INIS)

Zacchi, Flávia Lucena; Lima, Daína; Flores-Nunes, Fabrício de; Mattos, Jacó Joaquim; Lüchmann, Karim Hahn; Araújo de Miranda Gomes, Carlos Henrique; Bícego, Márcia Caruso; Taniguchi, Satie; Sasaki, Silvio Tarou; Dias Bainy, Afonso Celso

2017-01-01

Highlights: • Salinity effect on Crassostrea brasiliana exposed to phenanthrene. • Higher transcription of biotransformation genes under hyposmotic condition. • Elevated transcription of oxidative stress-related genes under hyposmotic condition. • Amino acid metabolism-related genes changes according to salinity. • Phenanthrene does not affect amino acid metabolism-related genes. - Abstract: Euryhaline animals from estuaries, such as the oyster Crassostrea brasiliana, show physiological mechanisms of adaptation to tolerate salinity changes. These ecosystems receive constant input of xenobiotics from urban areas, including polycyclic aromatic hydrocarbons (PAHs), such as phenanthrene (PHE). In order to understand the influence of salinity on the molecular responses of C. brasiliana exposed to PHE, oysters were acclimatized to different salinities (35, 25 and 10) for 15 days and then exposed to 100 μg L"−"1 PHE for 24 h and 96 h. Control groups were kept at the same salinities without PHE. Oysters were sampled for chemical analysis and the gills were excised for mRNA quantification by qPCR. Transcript levels of different genes were measured, including some involved in oxidative stress pathways, phases I and II of the xenobiotic biotransformation systems, amino acid metabolism, fatty acid metabolism and aryl hydrocarbon receptor nuclear translocator putative gene. Higher transcript levels of Sulfotransferase-like gene (SULT-like) were observed in oysters exposed to PHE at salinity 10 compared to control (24 h and 96 h); cytochrome P450 isoforms (CYP2AU1, CYP2-like1) were more elevated in oysters exposed for 24 h and CYP2-like2 after 96 h of oysters exposed to PHE at salinity 10 compared to control. These results are probably associated to an enhanced Phase I biotransformation activity required for PHE detoxification under hyposmotic stress. Higher transcript levels of CAT-like, SOD-like, GSTm-like (96 h) and GSTΩ-like (24 h) in oysters kept at salinity

Transcriptional changes in oysters Crassostrea brasiliana exposed to phenanthrene at different salinities

Energy Technology Data Exchange (ETDEWEB)

Zacchi, Flávia Lucena; Lima, Daína; Flores-Nunes, Fabrício de [Laboratory of Biomarkers of Aquatic Contamination and Immunochemistry − LABCAI, Federal University Santa Catarina, Florianópolis (Brazil); Mattos, Jacó Joaquim [Aquaculture Pathology Research Center – NEPAQ, Federal University of Santa Catarina, Florianópolis (Brazil); Lüchmann, Karim Hahn [Laboratory of Biochemistry and Molecular Biology – LBBM, Fishery Engineering Department, Santa Catarina State University, Laguna (Brazil); Araújo de Miranda Gomes, Carlos Henrique [Laboratory of Marine Mollusks – LMM, Federal University of Santa Catarina, Florianópolis (Brazil); Bícego, Márcia Caruso; Taniguchi, Satie; Sasaki, Silvio Tarou [Laboratory of Marine Organic Chemistry – LABQOM, Oceanographic Institute, University of São Paulo, São Paulo (Brazil); Dias Bainy, Afonso Celso, E-mail: afonso.bainy@ufsc.br [Laboratory of Biomarkers of Aquatic Contamination and Immunochemistry − LABCAI, Federal University Santa Catarina, Florianópolis (Brazil)

2017-02-15

Highlights: • Salinity effect on Crassostrea brasiliana exposed to phenanthrene. • Higher transcription of biotransformation genes under hyposmotic condition. • Elevated transcription of oxidative stress-related genes under hyposmotic condition. • Amino acid metabolism-related genes changes according to salinity. • Phenanthrene does not affect amino acid metabolism-related genes. - Abstract: Euryhaline animals from estuaries, such as the oyster Crassostrea brasiliana, show physiological mechanisms of adaptation to tolerate salinity changes. These ecosystems receive constant input of xenobiotics from urban areas, including polycyclic aromatic hydrocarbons (PAHs), such as phenanthrene (PHE). In order to understand the influence of salinity on the molecular responses of C. brasiliana exposed to PHE, oysters were acclimatized to different salinities (35, 25 and 10) for 15 days and then exposed to 100 μg L{sup −1} PHE for 24 h and 96 h. Control groups were kept at the same salinities without PHE. Oysters were sampled for chemical analysis and the gills were excised for mRNA quantification by qPCR. Transcript levels of different genes were measured, including some involved in oxidative stress pathways, phases I and II of the xenobiotic biotransformation systems, amino acid metabolism, fatty acid metabolism and aryl hydrocarbon receptor nuclear translocator putative gene. Higher transcript levels of Sulfotransferase-like gene (SULT-like) were observed in oysters exposed to PHE at salinity 10 compared to control (24 h and 96 h); cytochrome P450 isoforms (CYP2AU1, CYP2-like1) were more elevated in oysters exposed for 24 h and CYP2-like2 after 96 h of oysters exposed to PHE at salinity 10 compared to control. These results are probably associated to an enhanced Phase I biotransformation activity required for PHE detoxification under hyposmotic stress. Higher transcript levels of CAT-like, SOD-like, GSTm-like (96 h) and GSTΩ-like (24 h) in oysters kept at

Administrative norms on radiofrequency radiation for occupationally exposed persons

International Nuclear Information System (INIS)

Saxeboel, G.

1982-01-01

The report presents a proposal for administrative norms on radiofrequency (RF) radiation for occupationally exposed persons. The norms establish maximum allowable field exposure in a frequency range from 1 MHz too 300 GHz. (RF)

Nocardia brasiliensis endophthalmitis in a patient with an exposed Ahmed glaucoma drainage implant.

Science.gov (United States)

Stewart, Michael W; Bolling, James P; Bendel, Rick E

2013-01-01

To report a case of endophthalmitis due to Nocardia brasiliensis in an eye with an exposed, infected Ahmed glaucoma drainage implant (GDI). Retrospective case report. A patient with an exposed GDI experienced recurrent episodes of endophthalmitis despite repeated intravitreal injections of antibiotics and steroids. The tube was initially repositioned and finally removed. Whereas repeated cultures from the anterior chamber and vitreous were negative, cultures from the removed tube grew Nocardia brasiliensis. Despite oral trimethoprim-sulfamethoxazole and intravitreal amikacin the eye became phthisical and lost light perception. An exposed GDI may lead to endophthalmitis due to Nocardia brasiliensis and may require explantation to establish a diagnosis.

Uranium in the tissue of occupationally exposed workers

International Nuclear Information System (INIS)

Campbell, E.E.; McInroy, J.F.; Schulte, H.F.

1975-04-01

Data are presented on the content of uranium in tissue samples from deceased occupationally exposed uranium workers. Data on the distribution in lungs, lymph nodes, liver, kidneys, and bone tissues are correlated with available data on the urinary excretion of U during the period of occupational exposure. (CH)

46 CFR 108.223 - Guards on exposed equipment.

Science.gov (United States)

2010-10-01

... have hand covers, guards, or rails installed on all belts, gears, shafts, pulleys, sprockets, spindles... 46 Shipping 4 2010-10-01 2010-10-01 false Guards on exposed equipment. 108.223 Section 108.223 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN...

Warfarin binding to plasma of workers exposed to toluene diisocyanate

Energy Technology Data Exchange (ETDEWEB)

Bachmann, K.; Shapiro, R.; Forney, R.B. Jr.

1982-02-01

The extent of (14)C-warfarin binding to plasma proteins was evaluated in a group of normal, healthy volunteers and in two groups of individuals occupationally exposed to toluene diisocyanate (TDI). Plasma binding was assessed by ultrafiltration after the addition of racemic (14)C-warfarin to a final concentration of 0.8 microgram/ml. Chronic occupational exposure to TDI did not affect the extent of warfarin binding since warfarin free fractions (normalized to an albumin concentration of 4.5 g/dl) were 1.09 +/- 0.23 (mean +/- SD), 0.98 +/- 0.19, and 0.97 +/- 0.15 for controls and the two groups of TDI-exposed individuals, respectively.

Atomic friction at exposed and buried graphite step edges: Experiments and simulations

Energy Technology Data Exchange (ETDEWEB)

Ye, Zhijiang; Martini, Ashlie, E-mail: amartini@ucmerced.edu [School of Engineering, University of California Merced, 5200 N. Lake Road, Merced, California 95343 (United States)

2015-06-08

The surfaces of layered materials such as graphite exhibit step edges that affect friction. Step edges can be exposed, where the step occurs at the outmost layer, or buried, where the step is underneath another layer of material. Here, we study friction at exposed and buried step edges on graphite using an atomic force microscope (AFM) and complementary molecular dynamics simulations of the AFM tip apex. Exposed and buried steps exhibit distinct friction behavior, and the friction on either step is affected by the direction of sliding, i.e., moving up or down the step, and the bluntness of the tip. These trends are analyzing in terms of the trajectory of the AFM tip as it moves over the step, which is a convolution of the topography of the surface and the tip shape.

Atomic friction at exposed and buried graphite step edges: Experiments and simulations

International Nuclear Information System (INIS)

Ye, Zhijiang; Martini, Ashlie

2015-01-01

The surfaces of layered materials such as graphite exhibit step edges that affect friction. Step edges can be exposed, where the step occurs at the outmost layer, or buried, where the step is underneath another layer of material. Here, we study friction at exposed and buried step edges on graphite using an atomic force microscope (AFM) and complementary molecular dynamics simulations of the AFM tip apex. Exposed and buried steps exhibit distinct friction behavior, and the friction on either step is affected by the direction of sliding, i.e., moving up or down the step, and the bluntness of the tip. These trends are analyzing in terms of the trajectory of the AFM tip as it moves over the step, which is a convolution of the topography of the surface and the tip shape

Towards harmonized qualifications for radiation exposed personnel

International Nuclear Information System (INIS)

Briso, Hugo A.

2008-01-01

The accelerated process of globalization affecting mankind doesn't exclude safety matters. Indeed, some trans national corporations are increasingly offering specialized engineering services such as industrial radiography or well lodging. As well, a growing scientific exchange involves the mobility of nuclear researchers in different areas, for instance radiochemistry, nuclear medicine and radiotherapy. Such a breakdown in the technological frontiers must necessarily be reflected by the regulatory solutions. Particularly, diverse levels of theoretical-practical training for radiation exposed personnel coexist in the Latin-American Region, being an especially sensitive problem for radiation protection matters. The spectrum goes from post-graduate courses required for radiation protection officers in some countries, while in others only basic recommendations are required for the operating personnel. Another scheme consists of medium level course for the operating personnel, while radiation protection officers don't have special requirements. Many educational private institutions teach non standardized courses which only give broad concepts of radiation protection. On the other hand, usually nothing is said about the operational training, or else its certification is entrusted to the employer itself. In some countries multiple Regulatory Authorities apply dissimilar criteria to assess safety matters, including the evaluation of workers applications. The necessary regional integration makes indispensable to establish common standards for granting authorizations. Having similar or homogeneous requirements for the universe of radiation exposed personnel, i.e. source operators, radiation protection officers, qualified experts and technical support people would be easier for the Regulatory Authorities to have common methodologies of evaluation for the applicants. An IAEA supported technical cooperation project related to this paper seeks to establish standardized

Immunotoxic effects of iodine-131 in prenatally exposed rats

International Nuclear Information System (INIS)

Cole, D.A.; Stevens, R.H.; Lindholm, P.A.; Cheng, H.F.

1985-01-01

Present results suggest that offspring exposed in utero to radioactive iodine-131 develop a measureable cell-mediated immune (CMI) response. Regnant Fischer F344 inbred rats were exposed to 370 kBg to 3.7 MBg (10 to 100 μCi) Na 131I on 16 to 18 days of gestation and evaluated for CMI responsiveness 2 to 3 months post exposure using an 125I radiolabeled membrane release assay. Current data suggest that not only the F1, but also the F2 pups develop a measureable CMI response. In order to determine whether other immune functions are altered studies have been initiated to evaluate the immunotoxic effect of prenatal exposure to 131I. These studies include the evaluation of the delayed hypersensitivity response and the blastogenic responses to phytoheemagglutinin, concanavalin A, and lipopolysaccharide

Asthma Symptoms and Specific IgE Levels among Toluene Diisocyanate (TDI) Exposed Workers in Tehran, Iran.

Science.gov (United States)

Sharifi, Laleh; Karimi, Akram; Shokouhi Shoormasti, Raheleh; Miri, Sara; Heydar Nazhad, Hassan; Bokaie, Saied; Fazlollahi, Mohammad Reza; Sadeghniiat Haghighi, Khosro; Pourpak, Zahra; Moin, Mostafa

2013-01-01

Toluene diisocyanate (TDI) is an imperative chemical substance used in the production of polyurethane foams, elastomers, paints and coatings that cause a variety of health problems in workers who are exposed in work places. This study aimed to determine the asthma symptoms and serum specific IgE levels in TDI exposed workers and comparing the results with healthy control group. All the plants that use TDI in the manufacturing of paint and glue in the west of Tehran Province entered to the study and all the workers (550) completed modified initial questionnaire of the NIOSH, the questions were consisted of asthma symptoms. For each symptomatic exposed worker one healthy, sex and age matched control selected. Total IgE and Specific TDI IgE tests were done for each case and control groups. Among 550 TDI exposed workers, 26(4.7%) had asthma symptoms. Nine (34.6%) of symptomatic workers who were exposed to TDI were active cigarette consumer versus 3(11.5%) unexposed workers, P=0.049(CI= 0.953-17.29) OR=4.059. Nine (34.6%) workers had positive family history of atopy versus 1(3.8%) unexposed workers, P=0.0138 (CI= 1.45-305.41) OR=13.24. TDI specific IgE was found in 2 TDI exposed workers and 1 unexposed worker (P=0.5). Mean of total IgE was 339.05 in exposed workers (P=0.201). This study provides clinical and paraclinical data of workers exposed to TDI and points to a relation between atopy and smoking habit with asthma symptoms that offer preventing recommendations for TDI exposed workers and their heath administrators.

Genetic and demographic responses of mosquitofish (Gambusia holbrooki) populations exposed to mercury for multiple generations

Energy Technology Data Exchange (ETDEWEB)

Tatara, C.P.; Mulvey, M.; Newman, M.C.

1999-12-01

Genetic and demographic responses of mosquitofish were examined after multiple generations of exposure to mercury. Previous studies of acute lethal exposures of mosquitofish to either mercury or arsenic demonstrated a consistent correlation between time to death and genotype at the glucosephosphate isomerase-2 (Gpi-2) locus. A mesocosm study involving mosquitofish populations exposed to mercury for 111 d showed significant female sexual selection and fecundity selection at the Gpi-2 locus. Here the mesocosm study was extended to populations exposed to mercury for several (approx. four) generations. After 2 years, control and mercury-exposed populations met Hardy-Weinberg expectations and showed no evidence of genetic bottlenecks. The mean number of heterozygous loci did not differ significantly between the mercury-exposed and control populations. Significant differences in allele frequencies at the Gpi-2 locus were observed between the mercury-exposed and control populations. Relative to the initial and control allele frequencies, the GPI-2{sup 100} allele frequency was lower, the Gpi-2{sup 66} allele frequency increased, but the Gpi-2{sup 38} allele frequency did not change in mercury-exposed populations. No significant differences were found in standard length, weight, sex ratio, or age class ratio between the control and mercury-exposed populations. Allele frequency changes at the Gpi-2 locus suggest population-level response to chronic mercury exposure. Changes in allele frequency may be useful as indicators of population response to contaminants, provided that the population in question is well understood.

Visual selective attention is impaired in children prenatally exposed to opioid agonist medication.

Science.gov (United States)

Konijnenberg, Carolien; Melinder, Annika

2015-01-01

To examine whether prenatal exposure to opioid agonist medication is associated with visual selective attention and general attention problems in early childhood. Twenty-two children (mean age = 52.17 months, SD = 1.81) prenatally exposed to methadone, 9 children (mean age = 52.41 months, SD = 1.42) prenatally exposed to buprenorphine and 25 nonexposed comparison children (mean age = 51.44 months, SD = 1.31) were tested. Visual selective attention was measured with a Tobii 1750 Eye Tracker using a spatial negative priming paradigm. Attention problems were measured using the Child Behavior Checklist. The comparison group demonstrated a larger spatial negative priming effect (mean = 23.50, SD = 45.50) than the exposed group [mean = -6.84, SD = 86.39, F(1,50) = 5.91, p = 0.019, η(2) = 0.11]. No difference in reported attention problems was found [F(1,51) = 1.63, p = 0.21, η(2) = 0.03]. Neonatal abstinence syndrome and prenatal exposure to marijuana were found to predict slower saccade latencies in the exposed group (b = 54.55, SE = 23.56, p = 0.03 and b = 88.86, SE = 32.07, p = 0.01, respectively). Although exposed children did not appear to have attention deficits in daily life, lower performance on the SNP task indicates subtle alteration in the attention system. © 2014 S. Karger AG, Basel.

Liver function in patients exposed to a toluene in a hydrocarbon processing plant

International Nuclear Information System (INIS)

Sanchez, E; Fernandez D'Pool, J.

1996-01-01

Since the hepatotoxic role of toluene in exposed workers from the petroleum and petrochemical industries chronically exposed to low concentration has no been entirely dilucidated, this transversal study was undertaken in order to clarify the situation in the local industries. A group of 33 non-exposed men workers of such industries (group control, aged 33.0 +/- 4.88 years) were compared with 33 toluene-exposed men (aged 35.0 +/- 9.33 years) from the related industries, with a minimal of 6 months exposition time to toluene and without liver disease history. In addition to a complete occupational diseases medical history, each subject was tested by both a venous blood sample (to determine prothrombin, total and fractioned bilirubin, total and fractioned proteins, liver enzymes and cholesterol) and urine sample (hippuric acid). Also the environmental concentration of toluene in working areas was determined by gas chromatography, which was below the recommended standard levels in working areas. Although the analyzed parameters were in the normal range, it was observed that those workers with known alcohol ingestion and toluene exposition had several abnormalities. The results of this study confirm that toluene may have a synergistic hepatotoxic effect in toluene-exposed workers that are alcohol consumers. The alcohol in considered as a confounding factor and it is not possible to rule out in the etiology of hepatic changes detected in the study

Histomorphometric Evaluation of the Small Coronary Arteries in Rats Exposed to Industrial Noise

Directory of Open Access Journals (Sweden)

Ana Lousinha

2015-05-01

Full Text Available Morphological changes induced by industrial noise (IN have been experimentally observed in several organs. Histological observations of the coronary arteries showed prominent perivascular tissue and fibrosis among IN-exposed rats. The effects on the small arteries are unknown. Objective: To evaluate the histomorphometric changes induced by IN on rat heart small arteries. Methods: Twenty Wistar rats exposed to IN during a maximum period of seven months and 20 age-matched controls were studied. Hearts were transversely sectioned from ventricular apex to atria and a mid-ventricular fragment was selected for analysis. The histological images were obtained with an optical microscope using 400× magnifications. A total of 634 arterial vessels (298 IN-exposed and 336 controls were selected. The mean lumen-to-vessel wall (L/W and mean vessel wall-to-perivascular tissue (W/P ratios were calculated using image J software. Results: There were no differences between exposed and control animals in their L/W ratios (p = 0.687 and time variations in this ratio were non-significant (p = 0.110. In contrast, exposed animals showed lower W/P ratios than control animals (p < 0.001, with significant time variations (p = 0.004. Conclusions: Industrial noise induced an increase in the perivascular tissue of rat small coronary arteries, with significant development of periarterial fibrosis.

Brain abnormalities among the mentally retarded prenatally exposed atomic bomb survivors

International Nuclear Information System (INIS)

Schull, W.J.; Otake, Masanori; Nishitani, Hiromu; Hasuo, Kanehiro; Kobayashi, Takuro; Goto, Ikuo.

1992-07-01

An increased occurrence of severe mental retardation, with or without accompanying small head size, at specific gestational ages has been the most conspicuous effect on brain development of prenatal exposure to the bombings of Hiroshima and Nagasaki. A variety of biological mechanisms could be responsible for this finding, including cell killing and mismanaged neuronal migration. We describe here the findings on magnetic resonance imaging of the brains of five of these mentally retarded individuals, all of whom were exposed in the 8th through the 15th weeks following fertilization, the gestational period shown to be the most vulnerable to radiation-related damage. In the two cases exposed at the 8th or 9th week following fertilization, large areas of ectopic gray matter are seen, strong evidence of a failure of the neurons to migrate to their proper functional sites. The two individuals exposed in the 12th or 13th week show no readily recognized ectopic gray areas but do show mild macrogyria, which implies some impairment in the development of the cortical zone. Moreover, both have mega cisterna magna. Finally, the one individual seen who was exposed still later in development, in the 15th week, shows none of the changes seen in the other four individuals. This person's brain, though small, appears to have normal architecture. These findings are discussed in terms of the embryological events transpiring at the time of the prenatal exposure of these individuals to ionizing radiation. (author)

Environmental noise-exposed workers: event-related potentials, neuropsychological and mood assessment.

Science.gov (United States)

Chiovenda, Paola; Pasqualetti, Patrizio; Zappasodi, Filippo; Ercolani, Matilde; Milazzo, Daniele; Tomei, Gianfranco; Capozzella, Assuntina; Tomei, Francesco; Rossini, Paolo M; Tecchio, Franca

2007-09-01

Prolonged environmental noise exposure can induce pathogenic effects on various physical and psychosocial responses. The first aim of this study was to investigate whether long-term occupational noise exposure could affect neurophysiological, neuropsychological and emotional statuses, with particular respect to attention and working memory. The second aim was to evaluate the effects on the tactile P300 of a specific stressor (background traffic noise) vs a non-specific stress inductor (Stroop test). The comparison between a group of noise-exposed workers (traffic police officers), and a control group (office employees) did not show marked differences in cognitive and emotional profiles. The amplitude of the baseline cognitive potential (P300), recorded during a tactile (electric) discrimination task, resulted higher in noise-exposed workers than in controls, and this enhancement was associated with a lower level of trait anxiety and better mood profiles. Moreover, we found a wider P300 amplitude reduction in traffic police officers than in controls, under noisy conditions due to traffic. The effect of the Stroop test as a stress inductor was negligible and similar in the two groups. The wider amplitude of the non-auditory P300 in traffic police officers in the baseline condition could be a sign of cross-modal cerebral plasticity enhancing attentive processes in the 'stress-free' sensory channel. In addition, noise-exposed workers presented a higher cerebral sensitivity to stress selectively when they were exposed to the habitual environmental stressor.

Rapid Assessment of Anthropogenic Impacts of Exposed Sandy ...

African Journals Online (AJOL)

We applied a rapid assessment methodology to estimate the degree of human impact of exposed sandy beaches in Ghana using ghost crabs as ecological indicators. The use of size ranges of ghost crab burrows and their population density as ecological indicators to assess extent of anthropogenic impacts on beaches ...

'Unicorn' among rats exposed to mycotoxins from Fusarium.

Science.gov (United States)

Schoental, R

1983-05-01

A horn-like nodule developed in the middle of the forehead of a white rat, exposed perinatally to T-2 toxin and to zearalenone, the secondary metabolites of Fusarium. The hard nodule consisted mainly of keratine, derived from a squamous carcinoma spreading through the nasal turbinals and invading the brain.

Protecting exposed tissues with external ultrasonic super-hydration.

Science.gov (United States)

Silberg, Barry Neil

2006-01-01

The author contends that a technique preventing dehydration of exposed tissues, such as external ultrasonic super-hydration, will result in a lower morbidity rate, decreasing deep tissue pain, susceptibility to infection, fat necrosis, wound dehiscence, and improving recovery times. He discusses how he uses this technique in his aesthetic surgery practice.

Advances in treating exposed fractures.

Science.gov (United States)

Nogueira Giglio, Pedro; Fogaça Cristante, Alexandre; Ricardo Pécora, José; Partezani Helito, Camilo; Lei Munhoz Lima, Ana Lucia; Dos Santos Silva, Jorge

2015-01-01

The management of exposed fractures has been discussed since ancient times and remains of great interest to present-day orthopedics and traumatology. These injuries are still a challenge. Infection and nonunion are feared complications. Aspects of the diagnosis, classification and initial management are discussed here. Early administration of antibiotics, surgical cleaning and meticulous debridement are essential. The systemic conditions of patients with multiple trauma and the local conditions of the limb affected need to be taken into consideration. Early skeletal stabilization is necessary. Definitive fixation should be considered when possible and provisional fixation methods should be used when necessary. Early closure should be the aim, and flaps can be used for this purpose.

Studies of chromosomal aberrations in occupationally coal exposed population (coal cutters)

International Nuclear Information System (INIS)

Vijender Reddy, V.; Rudrama Devi, K.

1995-01-01

A detailed study was carried out among the 235 coal mine workers (coal cutters) and 215 unexposed individuals (controls) on cytogenetic effect of coal in peripheral blood lymphocytes. The frequencies of chromosomal aberrations were studied in exposed coal mine workers as well as in the control groups . The confounding factors like smoking drinking and combination of both were taken into account. There was a significant increase in the total number of aberrations among exposed population subjected to different habits like smoking and alcoholism compared to that of the controls. (author). 14 refs., 1 tab

Dynamic Metabolic Disruption in Rats Perinatally Exposed to Low Doses of Bisphenol-A.

Directory of Open Access Journals (Sweden)

Marie Tremblay-Franco

Full Text Available Along with the well-established effects on fertility and fecundity, perinatal exposure to endocrine disrupting chemicals, and notably to xeno-estrogens, is strongly suspected of modulating general metabolism. The metabolism of a perinatally exposed individual may be durably altered leading to a higher susceptibility of developing metabolic disorders such as obesity and diabetes; however, experimental designs involving the long term study of these dynamic changes in the metabolome raise novel challenges. 1H-NMR-based metabolomics was applied to study the effects of bisphenol-A (BPA, 0; 0.25; 2.5, 25 and 250 μg/kg BW/day in rats exposed perinatally. Serum and liver samples of exposed animals were analyzed on days 21, 50, 90, 140 and 200 in order to explore whether maternal exposure to BPA alters metabolism. Partial Least Squares-Discriminant Analysis (PLS-DA was independently applied to each time point, demonstrating a significant pair-wise discrimination for liver as well as serum samples at all time-points, and highlighting unequivocal metabolic shifts in rats perinatally exposed to BPA, including those exposed to lower doses. In BPA exposed animals, metabolism of glucose, lactate and fatty acids was modified over time. To further explore dynamic variation, ANOVA-Simultaneous Component Analysis (A-SCA was used to separate data into blocks corresponding to the different sources of variation (Time, Dose and Time*Dose interaction. A-SCA enabled the demonstration of a dynamic, time/age dependent shift of serum metabolome throughout the rats' lifetimes. Variables responsible for the discrimination between groups clearly indicate that BPA modulates energy metabolism, and suggest alterations of neurotransmitter signaling, the latter finding being compatible with the neurodevelopmental effect of this xenoestrogen. In conclusion, long lasting metabolic effects of BPA could be characterized over 200 days, despite physiological (and thus metabolic changes

Uniform Protection for Multi-exposed Targets

DEFF Research Database (Denmark)

Vigo, Roberto; Nielson, Flemming; Nielson, Hanne Riis

2014-01-01

the Quality Calculus that computes the combinations of data required to reach a program point and relates them to a notion of cost. In this way, we can compare the security deployed on different paths that expose the same resource. The analysis is formalised in terms of flow logic, and is implemented......Ensuring that information is protected proportionately to its value is a major challenge in the development of robust distributed systems, where code complexity and technological constraints might allow reaching a key functionality along various paths. We propose a protection analysis over...

Evidence for alteration of the membrane-bound ribosomes in Micrococcus luteus cells exposed to lead

Energy Technology Data Exchange (ETDEWEB)

Barrow, W; Himmel, M; Squire, P G; Tornabene, T G

1978-01-01

Micrococcus luteus cells exposed to Pb(NO/sub 3/)/sub 2/ contained cytosol ribosomal particles and disaggregated membranal ribosomal particles as determined by ultracentrifugation and spectral studies. Approximately 60% of the membrane ribosome fraction from lead exposed cells had a sedimentation value of 8.4S. Cytosol ribosome from lead exposed cells as well as membranal and cytosol ribosomes from control cells were comparable by their contents of predominantly the 70S type with the 50S and 100S present in relatively small amounts. The lead content of the 8.4S components was more than 200 times higher than the components with higher sedimentation coefficients from lead exposed cells and approximately 650 times more than that of control cell ribosomes. The cells exposed to lead, however, showed no adverse effects from the lead in respect to their growth rates and cellular yields. These results indicate that lead is interacting only at specific sites of the membrane and is inducing events initiated only in strategic cellular regions. These data further substantiate that subtle changes do occur in lead exposed cells that show no obvious effects. It is assumed that these minor alterations are, in toto, biologically significant. 24 references, 2 figures, 1 table.

[Respiratory symptoms and obstructive ventilatory disorder in Tunisian woman exposed to biomass].

Science.gov (United States)

Kwas, H; Rahmouni, N; Zendah, I; Ghédira, H

2017-06-01

In some Tunisian cities, especially semi-urbanized, the exposure to the smoke produced during combustion of the biomass, main source of pollution of indoor air, remains prevalent among non-smoking women. To assess the relationship between exposure to biomass smoke and the presence of obstructive ventilatory disorder in the non-smoking women in semi-urban areas of Tunisia. Cross etiological study, using a questionnaire, including 140 non-smoking women responsible for cooking and/or exposed during heating by traditional means with objective measurement of their respiratory functions. We found 81 women exposed to biomass for a period > or equal to 20 hours-years and 59 unexposed women. Exposed women reported more respiratory symptoms namely exertional dyspnea and/or chronic cough than unexposed. Of the 140 women, 14 women have an FEV/FEV6 biomass. We found a correlation between respiratory symptoms and obstructive ventilatory disorder in exposed women. The air pollution inside the home during the traditional activities of cooking and/or heating is a respiratory risk factor for non-smoking women over the age of 30 years. Exposure to biomass smoke can cause chronic respiratory symptoms and persistent obstructive ventilatory disorder that can be consistent with COPD. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Genotoxicity and oxidative stress in chromium-exposed tannery workers in North India.

Science.gov (United States)

Ambreen, Khushboo; Khan, Faizan Haider; Bhadauria, Smrati; Kumar, Sudhir

2014-06-01

Trivalent chromium (Cr) is an environmental contaminant, which is extensively used in tanning industries throughout the world and causes various forms of health hazards in tannery workers. Therefore, a cross-sectional study design was used to evaluate the DNA damage and oxidative stress condition in tannery workers exposed to Cr in North India. The study population comprised 100 male tanners in the exposed group and 100 healthy males (no history of Cr exposure) in the comparable control group. Baseline characteristics including age, smoking, alcohol consumption habits and duration of exposure were recorded via interviewing the subjects. Blood Cr level (measured by atomic absorption spectrophotometry), DNA damage (measured by comet assay) and oxidative stress parameters (malondialdehyde (MDA), glutathione (GSH) and superoxide dismutase (SOD)) were estimated in both the groups. As a result of statistical analysis, exposed group showed significantly higher level of Cr (p  0.05) on DNA damage and oxidative stress parameters in both the groups. In simple and multiple correlation analysis, DNA damage and oxidative stress parameters showed significant correlation with Cr level and duration of exposure in exposed group. The findings of the present study revealed that chronic occupational exposure to trivalent Cr may cause DNA damage and oxidative stress in tannery workers. © The Author(s) 2012.

Physiological and biochemical responses of small fish exposed to Athabasca oil sands sediment

International Nuclear Information System (INIS)

Tetrault, G.R.; Environment Canada, Burlington, ON; McMaster, M.E.; Dixon, D.G.; Parrott, J.L.

2002-01-01

A study was conducted to determine the influence of naturally occurring oil sands related compounds on the reproductive function and hepatic responses of fish. Wild fish, both exposed and unexposed to the compounds in question, were collected along with sediments for laboratory testing. The study showed that in vitro gonadal incubation levels of steroid production were lower at the tributary sites within the oil sands deposits. One indicator of exposure to oil sands related compounds (hepatic 7-ethoxyresorufin-O-deethylase activity) was shown to be 5 times higher at the same sites. In addition, slimy sculpin were exposed to sediment samples from the Steepbank River site for 4 to 8 days to evaluate the absorption of the indicator. The indicator in exposed fish was found to be comparable to that measured in fish native to the oil sands area. The study was not capable of predicting an altered ability of gonadal tissue of exposed fish to produce steroid hormones in vitro. It was concluded that future development could compromise the reproductive health of fish in the area

Sociological and socio-psycho-historical problems of A-bomb exposed twin

International Nuclear Information System (INIS)

Watanabe, Shoji

1983-01-01

The atomic bombing of Hiroshima brought many casualities on human society, and collapsed human communities. The purpose of this study is to make mainly on pairs of monozygotic twins one of whom was exposed and the other was not, or both of whom were exposed, a general socio-psycho-historical investigations through a twin control study to find whether the bombing, which can be considered to cause major environmental changes, has had any psychological effects on the individuals. Due to the limited sample of atomic bomb exposed twins, in numbers available for study, it is necessary to have an understanding for their condions of the living and identity they have developed from the numerous mental stress they suffered, and rapid socio-cultural changes they experienced, including for changes in life from birth until the atomic bombing and aftermath of the disaster. As the result of this study, by depth interview, projective psychological research and research on socio-psycho-history of exposed twin and the nonexposed before the A-bomb and aftermath of disaster, the following were obtained: a) Although at the age of four and eight they exposed, they still keep it in clear memory of the damage and suffering in the minds. b) The damage and suffereng of the family who belonged were relatively small, the effects of their psychological sufferings continued even after these thirtyseven years. c) In the aftermath of the A-bomb disaster, the psychological bond showed strengthen through crises and following social distress. d) During the long period since the bombing, those who did not experienced A-bombing, have shown high degree of support and co-operation on their familial and social role to their counterpart. e) Even though their social or medical effects of A-bombing are relatively limited, if their spouse or close relative suffer psychological stress caused by A-bomb, they too suffer from their similar experiences. (J.P.N.)

Potential contribution of exposed resin to ecosystem emissions of monoterpenes

Science.gov (United States)

Eller, Allyson S. D.; Harley, Peter; Monson, Russell K.

2013-10-01

Conifers, especially pines, produce and store under pressure monoterpene-laden resin in canals located throughout the plant. When the plants are damaged and resin canals punctured, the resin is exuded and the monoterpenes are released into the atmosphere, a process that has been shown to influence ecosystem-level monoterpene emissions. Less attention has been paid to the small amounts of resin that are exuded from branches, expanding needles, developing pollen cones, and terminal buds in the absence of any damage. The goal of this study was to provide the first estimate of the potential of this naturally-exposed resin to influence emissions of monoterpenes from ponderosa pine (Pinus ponderosa) ecosystems. When resin is first exuded as small spherical beads from undamaged tissues it emits monoterpenes to the atmosphere at a rate that is four orders of magnitude greater than needle tissue with an equivalent exposed surface area and the emissions from exuded beads decline exponentially as the resin dries. We made measurements of resin beads on the branches of ponderosa pine trees in the middle of the growing season and found, on average, 0.15 cm2 of exposed resin bead surface area and 1250 cm2 of total needle surface area per branch tip. If the resin emerged over the course of 10 days, resin emissions would make up 10% of the ecosystem emissions each day. Since we only accounted for exposed resin at a single point in time, this is probably an underestimate of how much total resin is exuded from undamaged pine tissues over the course of a growing season. Our observations, however, reveal the importance of this previously unrecognized source of monoterpenes emitted from pine forests and its potential to influence regional atmospheric chemistry dynamics.

Neurocognitive screening of lead-exposed andean adolescents and young adults.

Science.gov (United States)

Counter, S Allen; Buchanan, Leo H; Ortega, Fernando

2009-01-01

This study was designed to assess the utility of two psychometric tests with putative minimal cultural bias for use in field screening of lead (Pb)-exposed Ecuadorian Andean workers. Specifically, the study evaluated the effectiveness in Pb-exposed adolescents and young adults of a nonverbal reasoning test standardized for younger children, and compared the findings with performance on a test of auditory memory. The Raven Coloured Progressive Matrices (RCPM) was used as a test of nonverbal intelligence, and the Digit Span subtest of the Wechsler IV intelligence scale was used to assess auditory memory/attention. The participants were 35 chronically Pb-exposed Pb-glazing workers, aged 12-21 yr. Blood lead (PbB) levels for the study group ranged from 3 to 86 microg/dl, with 65.7% of the group at and above 10 microg/dl. Zinc protoporphyrin heme ratios (ZPP/heme) ranged from 38 to 380 micromol/mol, with 57.1% of the participants showing abnormal ZPP/heme (>69 micromol/mol). ZPP/heme was significantly correlated with PbB levels, suggesting chronic Pb exposure. Performance on the RCPM was less than average on the U.S., British, and Puerto Rican norms, but average on the Peruvian norms. Significant inverse associations between PbB/ZPP concentrations and RCPM standard scores using the U.S., Puerto Rican, and Peruvian norms were observed, indicating decreasing RCPM test performance with increasing PbB and ZPP levels. RCPM scores were significantly correlated with performance on the Digit Span test for auditory memory. Mean Digit Span scale score was less than average, suggesting auditory memory/attention deficits. In conclusion, both the RCPM and Digit Span tests were found to be effective instruments for field screening of visual-spatial reasoning and auditory memory abilities, respectively, in Pb-exposed Andean adolescents and young adults.

Preventing Alcohol-Exposed Pregnancy among American-Indian Youth

Science.gov (United States)

Jensen, Jamie; Kenyon, DenYelle Baete; Hanson, Jessica D.

2016-01-01

Research has determined that the prevention of alcohol-exposed pregnancies (AEP) must occur preconceptually, either by reducing alcohol intake in women planning pregnancy or at risk for becoming pregnant, or by preventing pregnancy in women drinking at risky levels. One such AEP prevention programme with non-pregnant American-Indian (AI) women is…

Optimization of radiological surveillance of occupationally-exposed workers in the Republic of Cuba

International Nuclear Information System (INIS)

1992-01-01

This works analyzes the results of the dosimetric control to occupationally-exposed workers. during the 1987-1990 period. It states a criterium for knowing when it will be necessary to give or not an individual dosimeter to occupationally-exposed workers. It also proposes to take the dosimeter away to a number of workers as a result of such criterium

Delinquent behaviors among students exposed to family violence in Quebec schools

Science.gov (United States)

Cénat, Jude Mary; Hébert, Martine; Blais, Martin; Lavoie, Francine; Guerrier, Mireille

2016-01-01

Objective Juvenile delinquency is one of the major public concerns in many countries. This study aims to document the association between exposure to interparental violence and delinquent behaviors among high school students in Quebec (Canada). Methods A representative sample of 8194 students aged 14–20 years was recruited in Quebec (Canada) high schools. Participants completed a questionnaire describing delinquent behaviors as well as exposure to interparental psychological and physical violence. Findings Overall, one out of two participants has experienced delinquent behaviors and 61.8% of them have reported having been exposed to at least one of the two forms of family violence. Overall, youth exposed to interparental violence are more likely to experience delinquent behaviors. Both psychological and physical interparental violence were significantly and independently associated with delinquent behaviors. Conclusion The findings of this study point out the vulnerability of youth exposed to interparental violence. They also highlight the need in the prevention of juvenile delinquency to focus not only on youth but also on both parents that may have been involved in family violence. PMID:28111591

Hydrodynamic and Sediment Responses of Open Channels to Exposed Pipe Encasements.

Directory of Open Access Journals (Sweden)

J Q Mao

Full Text Available The effects of exposed pipe encasements on the local variation of hydrodynamic and sediment conditions in a river channel are examined. Laboratory experiments are performed to assess the response of water level, flow regime and bed deformation to several representative types of concrete encasements. The experimental conditions considered are: three types of exposed pipe encasements exposed on the bed, including trapezoidal shape, circular-arc shape and polygonal shape, and three sets of discharges, including annual discharge, once-in-3-year flood, and once-in-50-year flood. Our experiments show that: (1 the amount of backwater definitely depends on the encasement geometric shape and the background discharge; (2 smaller discharges generally tend to induce local scour of river bed downstream of the encasement, and the order of sensitivity of bed deformation to the encasement geometric shape is trapezoidal > circular-arc > polygonal; (3 comparatively speaking, the polygonal encasement may be considered as a suitable protective structure for pipelines across alluvial rivers, with relatively modest effects on the local hydrodynamic conditions and bed stabilization.

Hydrodynamic and Sediment Responses of Open Channels to Exposed Pipe Encasements.

Science.gov (United States)

Mao, J Q; Zhang, H Q; Dai, H C; Yuan, B H; Hu, T F

2015-01-01

The effects of exposed pipe encasements on the local variation of hydrodynamic and sediment conditions in a river channel are examined. Laboratory experiments are performed to assess the response of water level, flow regime and bed deformation to several representative types of concrete encasements. The experimental conditions considered are: three types of exposed pipe encasements exposed on the bed, including trapezoidal shape, circular-arc shape and polygonal shape, and three sets of discharges, including annual discharge, once-in-3-year flood, and once-in-50-year flood. Our experiments show that: (1) the amount of backwater definitely depends on the encasement geometric shape and the background discharge; (2) smaller discharges generally tend to induce local scour of river bed downstream of the encasement, and the order of sensitivity of bed deformation to the encasement geometric shape is trapezoidal > circular-arc > polygonal; (3) comparatively speaking, the polygonal encasement may be considered as a suitable protective structure for pipelines across alluvial rivers, with relatively modest effects on the local hydrodynamic conditions and bed stabilization.

Serum butanol extractable iodine values for adolescents exposed in utero - Nagasaki

Energy Technology Data Exchange (ETDEWEB)

Burrow, G N; Hamilton, H B; Man, E B

1961-10-18

Serum BEI determinations were performed on 249 fifteen year old exposed and nonexposed apparently normal children all of whom were in utero at the time of the atomic bombing in Nagasaki, Japan. The girls were more mature in growth and development than the boys; the boys were probably near the peak stress of adolescent development. No statistically significant difference of BEI values was found between exposed and control groups. The trimester of gestation of the children at the time of exposure appeared to have no conclusive effect on the BEI value, but the number of subjects from each trimester was too small for satisfactory statistical analysis. Eleven females with goiter were analyzed separately. There was a slight preponderance of goiter in the exposed group, but the difference was not significant. The mean BEI value for the males was significantly lower than that for the females. The mean BEI values for Japanese adolescents are higher than for adolescents in the Middle Atlantic and New England states in the United States. 31 references, 2 tables.

Biomarkers of genetic damage in human populations exposed to pesticides

International Nuclear Information System (INIS)

Aiassa, Delia; Manas, Fernando; Bosch, Beatriz; Gentile, Natalia; Bernardi, Natali; Gorla, Nora

2012-01-01

The effect of pesticides on human, animal and environmental health has been cause of concern in the scientific community for a long time. Numerous studies have reported that pesticides are not harmless and that their use can lead to harmful biological effects in the medium and long term, in exposed human and animals, and their offspring. The importance of early detection of genetic damage is that it allows us to take the necessary measures to reduce or eliminate the exposure to the deleterious agent when damage is still reversible, and thus to prevent and to diminish the risk of developing tumors or other alterations. In this paper we reviewed the main concepts in the field, the usefulness of genotoxicity studies and we compiled studies performed during the last twenty years on genetic monitoring of people occupationally exposed to pesticides. we think that genotoxicity tests, including that include chromosomal aberrations, micronucleus, sister chromatid exchanges and comet assays, should be considered as essential tools in the implementation of complete medical supervision for people exposed to potential environmental pollutants, particularly for those living in the same place as others who were others have already developed some type of malignancy. This action is particularly important at early stages to prevent the occurrence of tumors, especially from environmental origins.

Vibrotactile stimulation: A non-pharmacological intervention for opioid-exposed newborns.

Directory of Open Access Journals (Sweden)

Ian Zuzarte

Full Text Available To examine the therapeutic potential of stochastic vibrotactile stimulation (SVS as a complementary non-pharmacological intervention for withdrawal in opioid-exposed newborns.A prospective, within-subjects single-center study was conducted in 26 opioid-exposed newborns (>37 weeks; 16 male hospitalized since birth and treated pharmacologically for Neonatal Abstinence Syndrome. A specially-constructed mattress delivered low-level SVS (30-60Hz, 10-12μm RMS, alternated in 30-min intervals between continuous vibration (ON and no vibration (OFF over a 6-8 hr session. Movement activity, heart rate, respiratory rate, axillary temperature and blood-oxygen saturation were calculated separately for ON and OFF.There was a 35% reduction in movement activity with SVS (p30 sec duration for ON than OFF (p = 0.003. Incidents of tachypneic breaths and tachycardic heart beats were each significantly reduced with SVS, whereas incidents of eupneic breaths and eucardic heart beats each significantly increased with SVS (p<0.03. Infants maintained body temperature and arterial-blood oxygen level independent of stimulation condition.SVS reduced hyperirritability and pathophysiological instabilities commonly observed in pharmacologically-managed opioid-exposed newborns. SVS may provide an effective complementary therapeutic intervention for improving autonomic function in newborns with Neonatal Abstinence Syndrome.

Computed temperature profile in materials exposed to gamma radiation

Energy Technology Data Exchange (ETDEWEB)

Ping, Tso Chin; Choong, Yap Siew; Seon, Chan Kam

1987-06-01

Computed temperature profiles are presented for the materials of lead, steel, concrete and water in curved shells, when they are exposed to gamma radiation. The results are based on the usual simplified theory of thermal conduction with an exponential heat source.

30 CFR 75.521 - Lightning arresters; ungrounded and exposed power conductors and telephone wires.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Lightning arresters; ungrounded and exposed... Electrical Equipment-General § 75.521 Lightning arresters; ungrounded and exposed power conductors and... leads underground shall be equipped with suitable lightning arresters of approved type within 100 feet...

Studies on the hazard of leukaemia and cancer in persons occupationally exposed to radiation

International Nuclear Information System (INIS)

Streffer, C.

1988-01-01

The mortality rates of British radiologists in dependence of the duration of their radiation work are compared with the general mortality rate in England and Wales, the mortality rates of men of the social class 1 and the mortality rates of practicing physicians. It turns out that the mortality by malignant diseases (leukemia and cancer) of persons exposed to radiation at work in nuclear plants is not considerably higher than it is for comparable groups of persons not exposed to radiation. Tumour entities of the GI tract have not been found either in the British radiologists exposed to radiation. (DG) [de

Changes in some Hematological Parameters and Thyroid Hormones in Rats Exposed to Pulsed Electromagnetic Field

International Nuclear Information System (INIS)

EL-Abiad, N.M.; Marzook, E.A.; EI-Aragi, G.M.

2007-01-01

In the present study pulsed electromagnetic spectrum was used to evaluate the effect of exposure on some biochemical and hematological parameters in male albino rats. Three groups of rats (10 each) were exposed to 10, 15, 20 pulses of electromagnetic spectrum 3 times per week for 3 weeks, the unexposed group was considered as the control group. At the end of experiment, serum levels of thyroid hormones triiodothryronine and thyroxine (T 3 ,T 4 ) and some hematological parameters were estimated. The hematological studies revealed that exposure to electromagnetic spectrum induced significant reduction in red blood cell count(RBC),and also in hemoglobin concentration(Hb), while reticulocytic count(Ret.) was elevated in the three exposed groups, platelets count was increased only on the second exposed group, while leukocytic count (WBC's), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MGH), mean corpuscular hemoglobin concentration (MCHC) were not affected, lymphocytic count was decreased only on the second exposed group, the impairment of thyroid functions was noticed by elevation of T 3 and T 4 in the three exposed groups

Metabolism of tritium uptake due to handling of metal surfaces exposed to tritiated hydrogen gas

International Nuclear Information System (INIS)

Johnson, J.R.; Peterman, B.F.

1987-08-01

Hairless rats were exposed to tritium by rubbing HT contaminated stainless steel planchets on them. The pattern of tritium excretion in the urine (n=4), shows the OBT (organically bound tritium) retention curve to be approximated by the sum of 2 exponential curves, one with a half-life of 0.4 days and another with a half-life of 1.4 days. The retention of HTO fit a single exponential curve with a half-life of 3.1 days. Exposed skin, unexposed skin, liver, muscle and blood (n=6) were assayed for HBO, and free HTO. Highest activity was found in the exposed skin, other organs with high activity are the unexposed skin and liver. Examination of the exposed skin showed HTO to be concentrated in the uppermost layers. The distribution of OBT was similar but was incorporated at a faster rate. The basal layer is exposed to a tritium concentration between 70-90% of that of the surface. The two macromolecule fractions with the highest amount of radioactivity were lipid and insoluble protein (mainly collagen)

Counseling Patients Exposed to Ionizing Radiation in Diagnostic Radiology During Pregnancy

International Nuclear Information System (INIS)

Brnic, Z.; Leder, N.I.; Popic Ramac, J.; Vidjak, V.; Knezevic, Z.

2013-01-01

There are many false assumptions regarding influence of radiation on pregnant patients and fetus during diagnostic procedures in spite of scientific facts based on studies (both in general population and among physicians). These false assumptions are mostly based on the idea that every diagnostic procedure that uses ionizing radiation is a cause for serious concern and consideration for artificial abortion as a possible solution. We have analysed the data of counselling of pregnant patients exposed to ionizing radiation during diagnostic procedures in University Hospital Merkur, during a period of four years. In this period we had 26 patients come in counselling due to exposure to ionizing radiation during pregnancy. Results show that most of these patients have been exposed to radiation between 2nd and 3rd week of gestation (36 %), between 4th and 5th week - 32 %; before 2nd week - 24%; and after 6th week of gestation less than 8 %. Average doses were: up to 0.01 cGy in 46.2 % patients; 0.01 - 0.15 cGy in 19.2 % patients; 0.2 - 1 cGy in 26.9 % and 1 cGy or more in 7.7 % of patients. No one of the counselled patients had a medical indication for abortion, even though in a small percentage of patients abortion was a personal subjective decision. Considering that there are no Croatian guidelines for counselling patients exposed to ionizing radiation during pregnancy, recommendation is to use International Commission on Radiological Protection (ICRP) guidelines for management of pregnant patients exposed to ionizing radiation.(author)

Individual doses' register of occupationally exposed persons in the Republic of Moldova

International Nuclear Information System (INIS)

Hustuc, A.; Chiruta, Iu.

2009-01-01

The storage and processing of the data acquired through different monitoring techniques are of vital importance for controlling the individual doses of the occupationally exposed workers facilitating the determination of exposure pathway and furthering the policy of radiological protection. The use of the data bases for the evidence of the individual doses of the occupationally exposed workers to the ionizing radiation is useful in studies of risks and potential exposure, and in future epidemiological studies. (authors)

A Sink-driven Approach to Detecting Exposed Component Vulnerabilities in Android Apps

OpenAIRE

Wu, Daoyuan; Luo, Xiapu; Chang, Rocky K. C.

2014-01-01

Android apps could expose their components for cooperating with other apps. This convenience, however, makes apps susceptible to the exposed component vulnerability (ECV), in which a dangerous API (commonly known as sink) inside its component can be triggered by other (malicious) apps. In the prior works, detecting these ECVs use a set of sinks pertaining to the ECVs under detection. In this paper, we argue that a more comprehensive and effective approach should start by a systematic selectio...

3. cotrimoxazole prophylaxis compliance among hiv exposed infants

African Journals Online (AJOL)

Esem

reported that their spouses knew about their HIV status and 65.7% said that they felt free to give their child cotrimoxazole in public.61.8% of the respondents did not know that there was a social support group for mothers/caretakers of HIV exposed infants in their community and 74.5% stated that there were misconceptions ...

Exposing the Myths, Defining the Future

International Nuclear Information System (INIS)

Slavov, S.

2013-01-01

With this official statement, the WEC calls for policymakers and industry leaders to ''get real'' as the World Energy Council as a global energy body exposes the myths by informing the energy debate and defines a path to a more sustainable energy future. The World Energy Council urged stakeholders to take urgent and incisive actions, to develop and transform the global energy system. Failure to do so could put aspirations on the triple challenge of WEC Energy Trilemma defined by affordability, accessibility and environmental sustainability at serious risk. Through its multi-year in-depth global studies and issue-mapping the WEC has found that challenges that energy sector is facing today are much more crucial than previously envisaged. The WEC's analysis has exposed a number of myths which influence our understanding of important aspects of the global energy landscape. If not challenged, these misconceptions will lead us down a path of complacency and missed opportunities. Much has, and still is, being done to secure energy future, but the WEC' s studies reveal that current pathways fall short of delivering on global aspirations of energy access, energy security and environmental improvements. If we are to derive the full economic and social benefits from energy resources, then we must take incisive and urgent action to modify our steps to energy solutions. The usual business approaches are not effective, the business as usual is not longer a solution. The focus has moved from large universal solutions to an appreciation of regional and national contexts and sharply differentiated consumer expectations.(author)

Exogenous ascorbic acid improves defence responses of sunflower (Helianthus annuus) exposed to multiple stresses.

Science.gov (United States)

Kaya, Armagan

2017-09-01

Ascorbic acid is an important antioxidant that plays role both on growth and development and also stress response of the plant. The purpose of this study was to determine the effect of ascorbate on physiological and biochemical changes of sunflower that was exposed to multiple stresses. Chlorophyll and carotenoid contents decreased and glutathione, ascorbate and malondialdehyde contents as well as antioxidant enzyme activities increased for sunflower plant that was exposed to 50 mM NaCl and pendimethalin at different concentrations. These changes were found to be more significant in groups simultaneously exposed to both stress factors. While malondialdehyde content decreased, chlorophyll, carotenoid, ascorbate, glutathione contents and antioxidant enzyme activities increased in plants treated exogenously with ascorbate, compared to the untreated samples. According to the findings of our study; compared to individual stress, the effect of stress is more pronounced in sunflower exposed to multiple stresses, and treatment with exogenous ascorbate reduces the negative effects of stress.

Parasite infection and immune and health-state in wild fish exposed to marine pollution.

Science.gov (United States)

Sueiro, María Cruz; Bagnato, Estefanía; Palacios, María Gabriela

2017-06-15

Association between parasitism and immunity and health-state was investigated in wild Sebastes oculatus after having determined that pollution exposure is associated with altered immune and health-state parameters. Given the importance of the immune system in antiparasite defense we predicted: (i) parasite infection would be higher in pollution-exposed than in control fish and (ii) fish with lower immune and health-state parameters would show higher parasitism than fish in better condition. Metazoan parasite fauna was compared between pollution-exposed and non-exposed fish and parasitic indices were correlated with integrated measures of immunity and health-state. Results provided little support for the predictions; some parasite taxa increased, some decreased, and some were not affected in pollution-exposed fish despite their altered health and immunity. Furthermore, there was no link between individual immune and health-state parameters and parasitism. These findings highlight the complexity of host-parasite-environment interactions in relation to pollution in natural marine ecosystems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Medical status of Marshallese accidentally exposed to 1954 Bravo fallout radiation: January 1988 through December 1991

Energy Technology Data Exchange (ETDEWEB)

Howard, J.E.; Heotis, P.M.; Scott, W.A.; Adams, W.H.

1995-07-01

The purpose of this report is to disseminate information concerning the medical status of 253 Marshallese exposed to fallout radiation in 1954. This report discusses the medical care provided and the medical findings for the years 1988-1991. Details of the BRAVO thermonuclear accident that caused the exposure have been published, and a 1955 article in the Journal of the American Medical Association describing the acute medical effects in the exposed population remains a definitive and relevant description of events. Participation in the Marshall Islands Medical Program by the exposed Marshallese is voluntary. In the spring and fall of each year, medical surveillance is provided to exposed and unexposed cohorts. Examinations performed include: a cancer-related examination as defined by the American Society, an annual thyroid examination and thyroid function testing, serum prolactin testing looking for pituitary tumors, annual blood counts to include platelets, and evaluation for paraneoplastic evidence of neoplasms. This report details the medical program, medical findings, and thyroid surgery findings. Deaths (4 exposed and 10 nonexposed) that occurred during the reporting period are discussed. There is a mild but relatively consistent depression of neutrophil, lymphocyte, and platelet concentrations in the blood of the exposed population. This depression appears to be of no clinical significance. Thyroid hypofunction, either clinical or biochemical, has been documented as a consequence of radiation exposure in 14 exposed individuals. Previously, one other exposed person was diagnosed with basal cell carcinoma. During this reporting period, a thyroid nodule was identified in an individual who was in utero during the exposure. Upon pathologic review, the nodule was diagnosed as occult papillary carcinoma.

Medical status of Marshallese accidentally exposed to 1954 Bravo fallout radiation: January 1988 through December 1991

International Nuclear Information System (INIS)

Howard, J.E.; Heotis, P.M.; Scott, W.A.; Adams, W.H.

1995-07-01

The purpose of this report is to disseminate information concerning the medical status of 253 Marshallese exposed to fallout radiation in 1954. This report discusses the medical care provided and the medical findings for the years 1988-1991. Details of the BRAVO thermonuclear accident that caused the exposure have been published, and a 1955 article in the Journal of the American Medical Association describing the acute medical effects in the exposed population remains a definitive and relevant description of events. Participation in the Marshall Islands Medical Program by the exposed Marshallese is voluntary. In the spring and fall of each year, medical surveillance is provided to exposed and unexposed cohorts. Examinations performed include: a cancer-related examination as defined by the American Society, an annual thyroid examination and thyroid function testing, serum prolactin testing looking for pituitary tumors, annual blood counts to include platelets, and evaluation for paraneoplastic evidence of neoplasms. This report details the medical program, medical findings, and thyroid surgery findings. Deaths (4 exposed and 10 nonexposed) that occurred during the reporting period are discussed. There is a mild but relatively consistent depression of neutrophil, lymphocyte, and platelet concentrations in the blood of the exposed population. This depression appears to be of no clinical significance. Thyroid hypofunction, either clinical or biochemical, has been documented as a consequence of radiation exposure in 14 exposed individuals. Previously, one other exposed person was diagnosed with basal cell carcinoma. During this reporting period, a thyroid nodule was identified in an individual who was in utero during the exposure. Upon pathologic review, the nodule was diagnosed as occult papillary carcinoma

Mitochondrial DNA damage and oxidative damage in HL-60 cells exposed to 900 MHz radiofrequency fields

Energy Technology Data Exchange (ETDEWEB)

Sun, Yulong; Zong, Lin; Gao, Zhen [School of Public Health, Soochow University, Suzhou, Jiangsu Province (China); Zhu, Shunxing [Laboratory Animal Center, Nantong University, Nantong, Jiangsu Province (China); Tong, Jian [School of Public Health, Soochow University, Suzhou, Jiangsu Province (China); Cao, Yi, E-mail: yicao@suda.edu.cn [School of Public Health, Soochow University, Suzhou, Jiangsu Province (China)

2017-03-15

Highlights: • Increased reactive oxygen species. • Decreased mitochondrial transcription Factor A and polymerase gamma. • Decreased mitochondrial transcripts (ND1 and 16S) and mtDNA copy number. • Increased 8-hydroxy-2′deoxyguanosine. • Decreased adenosine triphosphate. - Abstract: HL-60 cells, derived from human promyelocytic leukemia, were exposed to continuous wave 900 MHz radiofrequency fields (RF) at 120 μW/cm{sup 2} power intensity for 4 h/day for 5 consecutive days to examine whether such exposure is capable damaging the mitochondrial DNA (mtDNA) mediated through the production of reactive oxygen species (ROS). In addition, the effect of RF exposure was examined on 8-hydroxy-2′-dexoyguanosine (8-OHdG) which is a biomarker for oxidative damage and on the mitochondrial synthesis of adenosine triphosphate (ATP) which is the energy required for cellular functions. The results indicated a significant increase in ROS and significant decreases in mitochondrial transcription factor A, mtDNA polymerase gamma, mtDNA transcripts and mtDNA copy number in RF-exposed cells compared with those in sham-exposed control cells. In addition, there was a significant increase in 8-OHdG and a significant decrease in ATP in RF-exposed cells. The response in positive control cells exposed to gamma radiation (GR, which is also known to induce ROS) was similar to those in RF-exposed cells. Thus, the overall data indicated that RF exposure was capable of inducing mtDNA damage mediated through ROS pathway which also induced oxidative damage. Prior-treatment of RF- and GR-exposed the cells with melatonin, a well-known free radical scavenger, reversed the effects observed in RF-exposed cells.

Erosion of marker coatings exposed to Pilot-PSI plasma

NARCIS (Netherlands)

Paris, P.; Hakola, A.; Bystrov, K.; De Temmerman, G.; Aints, M.; I. Jõgi,; Kiisk, M.; Kozlova, J.; Laan, M.; Likonen, J.; Lissovski, A.

2013-01-01

In this article, laser induced breakdown spectroscopy (LIBS) has been used to study plasma-induced erosion processes. Samples with ITER-relevant coatings were exposed to controlled plasma fluxes whose parameters were characteristic to those occurring in the reactor walls. After the experiments,

Genomic damage in children accidentally exposed to ionizing radiation

DEFF Research Database (Denmark)

Fucic, A; Brunborg, G; Lasan, R

2007-01-01

During the last decade, our knowledge of the mechanisms by which children respond to exposures to physical and chemical agents present in the environment, has significantly increased. Results of recent projects and programmes focused on children's health underline a specific vulnerability of chil...... and efficient preventive measures, by means of a better knowledge of the early and delayed health effects in children resulting from radiation exposure....... of children to environmental genotoxicants. Environmental research on children predominantly investigates the health effects of air pollution while effects from radiation exposure deserve more attention. The main sources of knowledge on genome damage of children exposed to radiation are studies performed...... after the Chernobyl nuclear plant accident in 1986. The present review presents and discusses data collected from papers analyzing genome damage in children environmentally exposed to ionizing radiation. Overall, the evidence from the studies conducted following the Chernobyl accident, nuclear tests...

Studies on health risks to persons exposed to plutonium

International Nuclear Information System (INIS)

Voelz, G.L.; Stebbings, J.H. Jr.; Healy, J.W.; Hempelmann, L.H.

1979-01-01

Two studies on Los Alamos workers exposed to plutonium have shown no increase in cancers of the lung, bone, and liver, three principal cancers of interest following plutonium deposition. A clinical study of 26 workers exposed 32 years ago shows no cases of cancer other than two skin cancers that were excised successfully. A mortality study of 224 workers, all persons with estimated deposition of 10 nCi or moe in 1974, showed no excess of mortality due to any cause. No bone or liver cancers were present, while one death due to lung cancer was observed as compared to an expected three cases. These negative findings on such small groups are not able to prove or disprove the validity of commonly used risk estimates as recommended in the 1972 BEIR and 1977 UNSCEAR reports, but the data do indicate that much higher risk estimates are not warranted

Studies on health risks to persons exposed to plutonium

Energy Technology Data Exchange (ETDEWEB)

Voelz, G.L.; Stebbings, J.H. Jr.; Healy, J.W.; Hempelmann, L.H.

1979-01-01

Two studies on Los Alamos workers exposed to plutonium have shown no increase in cancers of the lung, bone, and liver, three principal cancers of interest following plutonium deposition. A clinical study of 26 workers exposed 32 years ago shows no cases of cancer other than two skin cancers that were excised successfully. A mortality study of 224 workers, all persons with estimated deposition of 10 nCi or moe in 1974, showed no excess of mortality due to any cause. No bone or liver cancers were present, while one death due to lung cancer was observed as compared to an expected three cases. These negative findings on such small groups are not able to prove or disprove the validity of commonly used risk estimates as recommended in the 1972 BEIR and 1977 UNSCEAR reports, but the data do indicate that much higher risk estimates are not warranted.

Association between sperm DNA integrity and seminal plasma antioxidant levels in health workers occupationally exposed to ionizing radiation

International Nuclear Information System (INIS)

Kumar, Dayanidhi; Salian, Sujith Raj; Kalthur, Guruprasad; Uppangala, Shubhashree; Kumari, Sandhya; Challapalli, Srinivas; Chandraguthi, Shrinidhi Gururajarao; Jain, Navya; Krishnamurthy, Hanumanthappa; Kumar, Pratap; Adiga, Satish Kumar

2014-01-01

There is a paucity of data regarding the association between occupational radiation exposure and risk to human fertility. Recently, we provided the first evidence on altered sperm functional characteristics, DNA damage and hypermethylation in radiation health workers. However, there is no report elucidating the association between seminal plasma antioxidants and sperm chromatin integrity in occupationally exposed subjects. Here, we assessed the seminal plasma antioxidants and lipid peroxidation level in 83 men who were occupationally exposed to ionizing radiation and then correlated with the sperm chromatin integrity. Flow cytometry based sperm chromatin integrity assay revealed a significant decline in αt value in the exposed group in comparison to the non-exposed group (P<0.0001). Similarly, both total and reduced glutathione levels and total antioxidant capacity in the seminal plasma were significantly higher in exposed group than the non-exposed group (P<0.01, 0.001 and 0.0001, respectively). However, superoxide dismutase level and malondialdehyde level, which is an indicator of lipid peroxidation in the seminal plasma, did not differ significantly between two groups. The total antioxidant capacity (TAC) and GSH level exhibited a positive correlation with sperm DNA integrity in exposed subjects. To conclude, this study distinctly shows that altered sperm chromatin integrity in radiation health workers is associated with increase in seminal plasma antioxidant level. Further, the increased seminal plasma GSH and TAC could be an adaptive measure to tackle the oxidative stress to protect genetic and functional sperm deformities in radiation health workers. - Highlights: • Seminal plasma antioxidants were measured in men occupationally exposed to radiation. • Sperm chromatin integrity was significantly affected in the exposed group. • Glutathione and total antioxidant capacity was significantly higher in exposed group. • Sperm DNA damage in exposed subjects

Association between sperm DNA integrity and seminal plasma antioxidant levels in health workers occupationally exposed to ionizing radiation

Energy Technology Data Exchange (ETDEWEB)

Kumar, Dayanidhi; Salian, Sujith Raj; Kalthur, Guruprasad; Uppangala, Shubhashree; Kumari, Sandhya [Division of Clinical Embryology, Department of Obstetrics and Gynecology, Kasturba Medical College, Manipal University, Manipal 576104 (India); Challapalli, Srinivas [Department of Radiotherapy, Kasturba Medical College, Mangalore (India); Chandraguthi, Shrinidhi Gururajarao [Department of Radiotherapy and Oncology, Kasturba Medical College, Manipal (India); Jain, Navya; Krishnamurthy, Hanumanthappa [National Centre for Biological Sciences, Bangalore (India); Kumar, Pratap [Department of Obstetrics and Gynecology, Kasturba Medical College, Manipal University, Manipal (India); Adiga, Satish Kumar, E-mail: satish.adiga@manipal.edu [Division of Clinical Embryology, Department of Obstetrics and Gynecology, Kasturba Medical College, Manipal University, Manipal 576104 (India)

2014-07-15

There is a paucity of data regarding the association between occupational radiation exposure and risk to human fertility. Recently, we provided the first evidence on altered sperm functional characteristics, DNA damage and hypermethylation in radiation health workers. However, there is no report elucidating the association between seminal plasma antioxidants and sperm chromatin integrity in occupationally exposed subjects. Here, we assessed the seminal plasma antioxidants and lipid peroxidation level in 83 men who were occupationally exposed to ionizing radiation and then correlated with the sperm chromatin integrity. Flow cytometry based sperm chromatin integrity assay revealed a significant decline in αt value in the exposed group in comparison to the non-exposed group (P<0.0001). Similarly, both total and reduced glutathione levels and total antioxidant capacity in the seminal plasma were significantly higher in exposed group than the non-exposed group (P<0.01, 0.001 and 0.0001, respectively). However, superoxide dismutase level and malondialdehyde level, which is an indicator of lipid peroxidation in the seminal plasma, did not differ significantly between two groups. The total antioxidant capacity (TAC) and GSH level exhibited a positive correlation with sperm DNA integrity in exposed subjects. To conclude, this study distinctly shows that altered sperm chromatin integrity in radiation health workers is associated with increase in seminal plasma antioxidant level. Further, the increased seminal plasma GSH and TAC could be an adaptive measure to tackle the oxidative stress to protect genetic and functional sperm deformities in radiation health workers. - Highlights: • Seminal plasma antioxidants were measured in men occupationally exposed to radiation. • Sperm chromatin integrity was significantly affected in the exposed group. • Glutathione and total antioxidant capacity was significantly higher in exposed group. • Sperm DNA damage in exposed subjects

Backfilling of trenches exposed to waves

DEFF Research Database (Denmark)

Hjelmager Jensen, Jacob; Fredsøe, Jørgen

1997-01-01

This paper treats the numerical prediction of initial and long-term morphology of small pipeline trenches. For this purpose a refined flow and sediment transport description is applied such that the entire mathematical problem is formulated and solved on a curvilinear grid using a k - ε turbulence......-closure. The backfilling process of trenches exposed to either waves or a steady current is of importance in relation to the implementation of pipelines in the marine environment. With respect to the sedimentation of trenches, the non-dimensional Trench-Keulegan-Carpenter number, KC = a/L, where a is the excursion length...

Granulocytes enzymes as a biomarker of radiotoxicity in exposed workers

International Nuclear Information System (INIS)

Milacic, S.; Jovicic, D.; Tanaskovic, I.; Marinkovic, O.; Milacic, S.)

2007-01-01

When radionuclide reaches the organism it causes internal irradiation and the lesions may be long lasting in various tissues. Enzymes in leukocytes will be used as a biomarkers of contamination with radio-nuclide in nuclear medicine workers. The analysed group had been consisted of 74 workers, exposed to radioactive isotopes J 131 and mTc 99 in nuclear medicine. Duration of occupational exposure (DOE) varied, so the groups with DOE of 1-5, 6-15, and 16-30 years, were compared to one another. The control group consisted of 52 subjects exposed to radionuclides (Cs 137 ) from environmental. Alkaline phosphatases and myeloperoxidase activity were inhibited in the granulocytes. The neutrophilic granulocytes count was lower while the number of eosinophils was higher

Cochlear condition and olivocochlear system of gas station attendants exposed to organic solvents

Directory of Open Access Journals (Sweden)

Tochetto, Tania Maria

2012-01-01

Full Text Available Introduction: Organic solvents have been increasingly studied due to its ototoxic action. Objective: Evaluate the conditions of outer hair cells and olivocochlear system in individuals exposed to organic solvents. Method: This is a prospective study. 78 gas station attendants exposed to organic solvents had been evaluated from three gas stations from Santa Maria city, Rio Grande do Sul (RS. After applying the inclusion criteria, the sample was constituted by 24 individuals. The procedures used on the evaluation were audiological anamnesis, Transient otoacoustic emissions (TEOAES and research for the suppressive effect of TEOAES. A group control (GC compounded by 23 individuals was compared to individuals exposed and non-exposed individuals. The data collection has been done in the room of Speech Therapy of Workers Health Reference Center of Santa Maria. Results: The TEOAES presence was major in the left ear in both groups; the average relation of TEOAES signal/noise in both ears was greater in GE; the TEOAES suppressive effect in the right ear was higher in the individual of GE (62,5% and in the left ear was superior in GC (86,96%, with statistically significant difference. The median sign/noise ratio of TEOAES, according to the frequency range, it was higher in GC in three frequencies ranges in the right ear and one in the left ear. Conclusion: It was not found signs of alteration on the outer hair cells neither on the olivocochlear medial system in the individuals exposed to organic solvents.

Utilization of soya protein as an alternative protein source in ...

African Journals Online (AJOL)

STORAGESEVER

2009-01-05

Jan 5, 2009 ... For carcass trait, ash, crude fat, and energy varied significantly with soya protein ... high-protein content, relatively well-balanced amino acid profile ..... and organoleptic quality of flesh of brook char (Salvelinus fontinalis).

Methane formation in tritium gas exposed to stainless steel

International Nuclear Information System (INIS)

Morris, G.A.

1977-01-01

Tests were performed to determine the effect cleanliness of a surface exposed to tritium gas had on methane formation. These tests performed on 304 stainless steel vessels, cleaned in various ways, showed that the methane formation was reduced by the use of various cleaning procedures

Thyroidal angiogenesis in zebrafish (Danio rerio) exposed to high ...

African Journals Online (AJOL)

STORAGESEVER

2009-04-20

Apr 20, 2009 ... As a well known environmental contaminant, perchlorate inhibits thyroidal iodide uptake and reduces thyroid hormone levels. In zebrafish (Danio rerio) exposed to high concentrations of sodium perchlorate (200, 350 and 500 mg/L) for 10 days, remarkable angiogenesis was identified, not only.

Experimental Infection and Clearance of Coccidian Parasites in Mercury-Exposed Zebra Finches.

Science.gov (United States)

Ebers Smith, Jessica H; Cristol, Daniel A; Swaddle, John P

2018-01-01

Mercury is a globally distributed, persistent environmental contaminant that affects the health of many taxa. It can suppress the immune system, which often plays a role in defense against parasites. However, there have been few investigations of whether mercury affects the abilities of animals to resist parasitic infection. Here, we exposed zebra finches to a lifetime dietary exposure of methylmercury (1.2 μg/g wet weight) and experimentally infected them with coccidian parasites to examine the effect of methylmercury exposure on parasitic infection. The mercury-exposed birds did not have an altered immune response (heterophil:lymphocyte ratio) nor a reduced ability to clear the infection. However, mercury-exposed birds tended to have higher parasite loads at the time when we expected the greatest immune response (2-3 weeks post-infection). Although mercury did not greatly influence the infection-course of this parasite in captivity, responses may be more accentuated in the wild where birds face additional immune challenges.

46 CFR 169.721 - Storm sails and halyards (exposed and partially protected waters only).

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Storm sails and halyards (exposed and partially... § 169.721 Storm sails and halyards (exposed and partially protected waters only). (a) Unless clearly unsuitable, each vessel must have one storm trysail of appropriate size. It must be sheeted independently of...

Behavior of cardiac variables in animals exposed to cigarette smoke

Directory of Open Access Journals (Sweden)

Sergio Alberto Rupp de Paiva

2003-09-01

Full Text Available OBJECTIVE: To assess the behavior of cardiac variables in animals exposed to cigarette smoke. METHODS: Two groups of Wistar rats were studied as follows: control group (C, comprising 28 animals; and smoking group (S, comprising 23 animals exposed to cigarette smoke for 30 days. Left ventricular cardiac function was assessed in vivo with transthoracic echocardiography, and myocardial performance was analyzed in vitro in preparations of isolated left ventricular papillary muscle. The cardiac muscle was assessed in isometric contractions with an extracellular calcium concentration of 2.5 mmol/L. RESULTS: No statistical difference was observed in the values of the body variables of the rats and in the mechanical data obtained from the papillary muscle between the control and smoking groups. The values of left ventricular systolic diameter were significantly greater in the smoking animals than in the control animals (C= 3.39 ± 0.4 mm and S= 3.71 ± 0.51 mm, P=0.02. A significant reduction was observed in systolic shortening fraction (C= 56.7 ± 4.2% and S= 53.5 ± 5.3%, P=0.02 and in ejection fraction (C= 0.92 ± 0.02 and S= 0.89 ± 0.04, P=0.01. CONCLUSION: The rats exposed to cigarette smoke had a reduction in left ventricular systolic function, although their myocardial function was preserved.

Evaluation of radiation protection educational level of professional exposed workers

International Nuclear Information System (INIS)

Marinkovic, O.; Krstev, S.; Jovanovic, S.

2006-01-01

Full text: Serbia and Montenegro legislation concerning with radiation protection was upgrading after publication ICRP- 60 and B.S.S., No.115. Present Law on the Protection against Ionizing Radiation is in force from 1996. Among quite new issues in radiation protection regulations there was article relate to obligatory refresher training. Due to adverse political and economic situation through many years radiation protection regulations were not fulfill completely. The aim of this investigation was to get real view to education level of professional exposed workers. In Serbia and Montenegro the most of ionizing radiation sources are in medical use and the most exposed workers are radiographers and radiologists. The test was passed by 200 radiographers and 50 radiologists. Main groups of questions were: Radiation protection and safety; difference between safety and security; legislation: law and regulations; incidents, accidents and operational failures: recording, learning. Usually, knowledge from school pales. New quantities (as ambient and personal dose equivalent) are mostly unknown. It is easier to understand the real difference between safety and security than to understand linguistic differences. Discussing regulations workers are more interesting in syndicate regulations than radiation protection ones. Operational failures and incidents are hidden. Better to say: nobody dare to speak about them. The results imposed conclusion that regulatory body has to pay more attention to upraise safety culture and radiation protection education level of professional exposed workers. (authors)

B-cell infiltration in the respiratory mucosa of turkeys exposed to subtype C avian metapneumovirus.

Science.gov (United States)

Cha, Ra Mi; Khatri, Mahesh; Sharma, Jagdev M

2007-09-01

Turkeys exposed to avian metapneumovirus (aMPV) subtype C showed extensive lymphoid cell infiltrations in the nasal turbinates of the upper respiratory tract. The cellular infiltration occurred after the first virus exposure but not after re-exposure. Quantitation of the relative proportions of mucosal immunoglobulin (Ig)A+, IgG+, and IgM+ cells in controls and virus-exposed turkeys revealed that at 7 days after the first virus exposure, when mucosal infiltration was well pronounced, there was a significant increase (P < 0.05) in the numbers of infiltrating IgA+ but not of IgG+ and IgM+ cells. After the second virus exposure, although the overall numbers of mucosal lymphoid cells were similar in the virus-exposed and control turkeys, the relative proportions of IgA+ and IgG+ cells were significantly higher in the virus-exposed turkeys (P < 0.05) than in controls. Furthermore, elevated levels of aMPV-specific IgA were detected in the nasal secretions and the bile of virus-exposed birds after the second but not after the first virus exposure. These results suggest, for the first time, the possible involvement of local mucosal immunoglobulins in the pathogenesis of aMPV in turkeys.

Cytogenetic follow-up of patients exposed, 7.5 years after radiological accident in Goiania, Brazil

International Nuclear Information System (INIS)

Ramalho, Adriana T.

1996-01-01

Ten persons exposed to 137 Cs during the radiological accident in Goiania (Brazil) were reexamined for the frequency of unstable chromosomal aberrations (dicentric chromosomes, centric rings and acentric fragments) 7.5 years the first examination. It was found that the frequencies fell to about 5% of the initial values, for those individuals who had been exposed to moderate to high doses. For the subjects exposed to low doses, of the order of 0.2 Gy or less., the observed frequencies of chromosomal aberrations fell much more slowly. (author)

Thyroidal angiogenesis in zebrafish ( Danio rerio ) exposed to high ...

African Journals Online (AJOL)

As a well known environmental contaminant, perchlorate inhibits thyroidal iodide uptake and reduces thyroid hormone levels. In zebrafish (Danio rerio) exposed to high concentrations of sodium perchlorate (200, 350 and 500 mg/L) for 10 days, remarkable angiogenesis was identified, not only histopathologically but also ...

Spatial variability of macrobenthic zonation on exposed sandy beaches

Science.gov (United States)

Veiga, Puri; Rubal, Marcos; Cacabelos, Eva; Maldonado, Cristina; Sousa-Pinto, Isabel

2014-07-01

We analysed the consistence of vertical patterns of distribution (i.e. zonation) for macrofauna at different spatial scales on four intermediate exposed beaches in the North of Portugal. We tested the hypothesis that biological zonation on exposed sandy beaches would vary at the studied spatial scales. For this aim, abundance, diversity and structure of macrobenthic assemblages were examined at the scales of transect and beach. Moreover, the main environmental factors that could potentially drive zonation patterns were investigated. Univariate and multivariate analyses revealed that the number of biological zones ranged from two to three depending on the beach and from indistinct zonation to three zones at the scale of transect. Therefore, results support our working hypothesis because zonation patterns were not consistent at the studied spatial scales. The median particle size, sorting coefficient and water content were significantly correlated with zonation patterns of macrobenthic assemblages. However, a high degree of correlation was not reached when the total structure of the assemblage was considered.

[Croatian and international regulations on the protection and rights of workers exposed to asbestos at work].

Science.gov (United States)

Zavalić, Marija; Macan, Jelena

2009-11-01

New regulations on the protection and rights of workers occupationally exposed to asbestos were introduced in Croatia in 2007 and 2008. They have been harmonised with the European Union (EU) and International Labour Organization (ILO) regulations, and make a step forward in safety at work, health protection, social rights, and pension schemes for Croatian workers occupationally exposed to asbestos. The 2007 Croatian regulation on the protection of workers from the risks related to exposure to asbestos at work defines and describes activities in which workers can be occupationally exposed to asbestos, defines the threshold value of asbestos in the air at work, defines valid methods for measurement of asbestos concentrations in the air, and establishes measures to reduce asbestos exposure at work or protect the exposed workers. Croatian law regulating obligatory health surveillance of workers occupationally exposed to asbestos from year 2007 defines activities and competent authorities to implement health surveillance of workers occupationally exposed to asbestos and to diagnose occupational diseases related to asbestos. This law also defines "occupational exposure to asbestos", and "occupational asbestos-related diseases", including asbestosis (pulmonary asbestos-related fibrosis), pleural asbestos-related disorders (plaques, pleural thickening, and benign effusion), lung and bronchial cancer, and malignant mesothelioma of serous membranes. These regulations have been harmonised with ILO, Directive 2003/18/EC amending Council Directive 83/477/EEC on the protection of workers from the risks related to exposure to asbestos at work, and with the Commission Recommendation 2003/670/EC concerning the European schedule of occupational diseases. The 2008 Croatian regulation on conditions of health surveillance, diagnostic procedures and criteria for confirmation of occupational asbestos-related diseases "defines the terms and the content of medical examination of workers

Pulmonary function evaluations of dogs exposed to uranium ore dust

International Nuclear Information System (INIS)

Loscutoff, S.M.; Buschbom, R.L.; Palmer, R.F.; Cross, F.T.

1980-01-01

Pulmonary function evaluations were conducted on dogs exposed to carnotite uranium ore dust. Significant changes were detected in the slope of the single-breath N 2 washout curve, suggesting an uneven distribution of ventilation

Hearing loss in workers exposed to epoxy adhesives and noise: a cross-sectional study.

Science.gov (United States)

Yang, Hsiao-Yu; Shie, Ruei-Hao; Chen, Pau-Chung

2016-02-18

Epoxy adhesives contain organic solvents and are widely used in industry. The hazardous effects of epoxy adhesives remain unclear. The objective of this study was to investigate the risk of hearing loss among workers exposed to epoxy adhesives and noise. Cross-sectional study. For this cross-sectional study, we recruited 182 stone workers who were exposed to both epoxy adhesives and noise, 89 stone workers who were exposed to noise only, and 43 workers from the administrative staff who had not been exposed to adhesives or noise. We obtained demographic data, occupational history and medical history through face-to-face interviews and arranged physical examinations and pure-tone audiometric tests. We also conducted walk-through surveys in the stone industry. A total of 40 representative noise assessments were conducted in 15 workplaces. Air sampling was conducted at 40 workplaces, and volatile organic compounds were analysed using the Environmental Protection Agency (EPA) TO-15 method. The mean sound pressure level was 87.7 dBA (SD 9.9). The prevalence of noise-induced hearing loss was considerably increased in the stone workers exposed to epoxy adhesives (42%) compared with the stone workers who were not exposed to epoxy adhesives (21%) and the administrative staff group (9.3%). A multivariate logistic regression analysis revealed that exposure to epoxy adhesives significantly increased the risk of hearing loss between 2 and 6 kHz after adjusting for age. Significant interactions between epoxy adhesives and noise and hearing impairment were observed at 3, 4 and 6 kHz. Epoxy adhesives exacerbate hearing impairment in noisy environments, with the main impacts occurring in the middle and high frequencies. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Lipid peroxidation in workers exposed to hexavalent chromium.

Science.gov (United States)

Huang, Y L; Chen, C Y; Sheu, J Y; Chuang, I C; Pan, J H; Lin, T H

1999-02-26

The aim of this study was to investigate whether exposure to hexavalent chromium induces lipid peroxidation in human. This study involved 25 chrome-plating factory workers and a reference group of 28 control subjects. The whole-blood and urinary chromium concentrations were determined by graphite furnace atomic absorption spectrophotometry. Malondialdehyde (MDA), the product of lipid peroxidation, was determined by high-performance liquid chromatography, and the activities of protective enzymes were measured by ultraviolet-visible spectrophotometry. In the chrome-plating workers, the mean concentrations of chromium in blood and urine were 5.98 microg/L and 5.25 microg/g creatinine, respectively; the mean concentrations of MDA in blood and urine were 1.7 micromol/L and 2.24 micromol/g creatinine. The concentrations of both chromium and MDA in blood and urine were significantly higher in the chromium-exposed workers. The activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) were not markedly different between control and exposed workers. Data suggest that MDA may be used as a biomarker for occupational chromium exposure. Antioxidant enzymic activities are not a suitable marker for chromium exposure.

From "Buzzword" to Best Practice: Applying Intersectionality to Children Exposed to Intimate Partner Violence.

Science.gov (United States)

Etherington, Nicole; Baker, Linda

2016-03-07

Empirical studies on the impact of intimate partner violence (IPV) on children have burgeoned over the last three decades. Notably absent from existing approaches to studying children exposed to IPV, however, is attention to how various positionalities intersect to impact the experiences of children and their families. In fact, while the importance of an intersectional framework for understanding IPV has been discussed for over two decades, little or no attention has been given to issues of children's exposure to IPV. In this article, we examine the current state of the literature on children exposed to IPV through an exploratory meta-analysis, finding limited application of intersectionality and a focus on discrete categories of difference. We then demonstrate why and how an intersectional framework should be applied to children exposed to IPV, with specific strategies for research and policy. We suggest a child-centered approach that recognizes diversity among children exposed to IPV, extending the challenge to traditional "one-size-fits-all" models to include an intersectionality-informed stance. © The Author(s) 2016.

Seroprevalence of Hepatitis C Virus in People Exposed to ...

African Journals Online (AJOL)

This study was therefore undertaken to determine the seroprevalence of hepatitis C virus (HCV) infection in people who had been exposed to traditional surgical practices in Edo State, Nigeria. Sera from the subjects were tested for HCV antibodies using Clinotech Diagnostic test device supplied by Clinotech Diagnostic and ...

Predictors of incident tuberculosis in HIV-exposed children in ...

African Journals Online (AJOL)

Objective: To examine the predictors of tuberculosis infection in HIV-exposed children. Design: A longitudinal cohort study nested within a randomised controlled trial. Setting: Antenatal clinics in Dar-es-Salaam, Tanzania. Subjects: Children born to 875 HIV-infected women in Tanzania. Results: A total of 82 children ...

The distribution of chromosome aberrations among chromosomes of karyotype in exposed human lymphocyte

International Nuclear Information System (INIS)

Que Tran; Tien Hoang Hung

1997-01-01

Induced chromosome aberrations (ch. ab.) in exposed Human peripheral blood lymphocyte have been used to assay radio.bio.doses, because of their characters such as: the maintaining Go phase in cell cycle in body, the distribution of cell in blood system and the distribution of ch. ab. in exposed cells of body and among chromosomes of karyotype. The frequency of ch. ab. reflected the quantity of radiation dose, dose rate and radiation energy. The dependence between radiation dose and frequency of ch. ab. was illustrated by the mathematic equations. The distribution of induced ch. ab. among the cells exposed to uniform radiation fields was Poisson's, but the distribution of ch. ab. among chromosomes in karyotype depended on radiation field and mononucleotid sequence of DNA molecular of each chromosome. The minimum influence of mononucleotid sequence of DNA molecular in inform ch. ab. will be advantageous state for dose-assessments. The location of induced ch. ab. in exposed Human lymphocyte had been determined by karyotype analyses. The data of statistic analyse had improved that the number of ch. ab. depended on the size of chromosomes in karyotype. The equal distribution of ch. ab.among chromosomes in karyotype provided the objectiveness and the accuracy of using the chromosomal aberrant analysis technique on bio-dosimetry. (author)

Lymphocytic subsets in occupationally exposed persons

International Nuclear Information System (INIS)

Tuschl, H.; Kovac, R.; Wottawa, A.

1989-04-01

The percentage of CD2, CD4, CD8 and NK cells of peripheral blood was investigated in persons occupationally exposed to very low doses of ionizing radiation. Investigations were carried out by monoclonal antibodies and flow-cytometry. While significant effects of age and smoking habits on the relative number of CD8 cells and CD4/CD8 ratios could be established, no influence of the very low radiation exposure on the profile of lymphocytic cells in blood was found, except a very slight effect on the relative number of total T cells (= CD2 cells). 7tabs., 2figs., 16refs. (Author)

Microbial diversity in firework chemical exposed soil and water samples collected in Virudhunagar district, Tamil Nadu, India.

Science.gov (United States)

Dhasarathan, P; Theriappan, P; Ashokraja, C

2010-03-01

Microbial diversity of soil and water samples collected from pyrochemicals exposed areas of Virdhunagar district (Tamil Nadu, India) was studied. Soil and water samples from cultivable area, waste land and city area of the same region were also studied for a comparative acount. There is a remarkable reduction in total heterotrophic bacterial population (THB) in pyrochemicals exposed soil and water samples (42 × 10(4) CFU/g and 5.6 × 10(4) CFU/ml respectively), compared to the THB of cultivable area soil and water samples (98 × 10(7) CFU/g and 38.6 × 10(7) CFU/ml). The generic composition the THB of the pyrochemicals exposed samples too exhibited considerable change compared to other samples. Pseudomonas sp. was the predominant one (41.6%) followed by Achromobacter sp. (25%) in pyrochemical exposed soil and Pseudomonas sp. was the predominant one (25%) in pyrochemical exposed water samples followed by Bacillus sp. (25%) and Micrococcus sp. (16.6%). It was observed that Cornybacterium sp. and Micrococcus sp. were absent completely in pyrochemical exposed soil and Achromobacter sp. was missing in the pyrochemical exposed water samples, which were present in the other samples. The outcome of this study clearly demonstrates that pollutants such as chemicals used in pyrotechniques affect the microbial biodiversity and suitable measures have to be taken to control the pollution level and to save biodiversity.

Durability of fibre reinforced concrete structures exposed to combined mechanical and environmental load

DEFF Research Database (Denmark)

Hansen, Ernst Jan De Place; Hansen, Kurt Kielsgaard

1999-01-01

The main conclusions from a research project on durability of cracked fibre reinforced concrete structures exposed to chlorides, water or freeze-thaw are presented. The effect of fibres and cracks on the durability of concrete is studied.......The main conclusions from a research project on durability of cracked fibre reinforced concrete structures exposed to chlorides, water or freeze-thaw are presented. The effect of fibres and cracks on the durability of concrete is studied....

Interaction of Al with O{sub 2} exposed Mo{sub 2}BC

Energy Technology Data Exchange (ETDEWEB)

Bolvardi, Hamid; Music, Denis, E-mail: music@mch.rwth-aachen.de; Schneider, Jochen M.

2015-03-30

Highlights: • Al adheres to many surfaces. • Solid–solid interactions challenging for real (oxidized) surfaces. • Dissociative O{sub 2} adsorption on Mo{sub 2}BC(0 4 0). • Al nonamer is disrupted on oxidized Mo{sub 2}BC(0 4 0). • Adhesion of a residual Al on the native oxide. - Abstract: A Mo{sub 2}BC(0 4 0) surface was exposed to O{sub 2}. The gas interaction was investigated using ab initio molecular dynamics and X-ray photoelectron spectroscopy (XPS) of air exposed surfaces. The calculations suggest that the most dominating physical mechanism is dissociative O{sub 2} adsorption whereby Mo−O, O−Mo−O and Mo{sub 2}−C−O bond formation is observed. To validate these results, Mo{sub 2}BC thin films were synthesized utilizing high power pulsed magnetron sputtering and air exposed surfaces were probed by XPS. MoO{sub 2} and MoO{sub 3} bond formation is observed and is consistent with here obtained ab initio data. Additionally, the interfacial interactions of O{sub 2} exposed Mo{sub 2}BC(0 4 0) surface with an Al nonamer is studied with ab initio molecular dynamics to describe on the atomic scale the interaction between this surface and Al to mimic the interface present during cold forming processes of Al based alloys. The Al nonamer was disrupted and Al forms chemical bonds with oxygen contained in the O{sub 2} exposed Mo{sub 2}BC(0 4 0) surface. Based on the comparison of here calculated adsorption energy with literature data, Al−Al bonds are shown to be significantly weaker than the Al−O bonds formed across the interface. Hence, Al−Al bond rupture is expected for a mechanically loaded interface. Therefore the adhesion of a residual Al on the native oxide layer is predicted. This is consistent with experimental observations. The data presented here may also be relevant for other oxygen containing surfaces in a contact with Al or Al based alloys for example during forming operations.

Nasal biopsies of children exposed to air pollutants.

Science.gov (United States)

Calderón-Garcidueñas, L; Rodriguez-Alcaraz, A; Valencia-Salazar, G; Mora-Tascareño, A; García, R; Osnaya, N; Villarreal-Calderón, A; Devlin, R B; Van Dyke, T

2001-01-01

Southwest Metropolitan Mexico City (SWMMC) atmosphere is a complex mixture of air pollutants, including ozone, particulate matter, and aldehydes. Children in SWMMC are exposed chronically and sequentially to numerous toxicants, and they exhibit significant nasal damage. The objective of this study was to assess p53 accumulation by immunohistochemistry in nasal biopsies of SWMMC children. We evaluated 111 biopsies from 107 children (83 exposed SWMMC children and 24 control children residents in a pollutant-compliant Caribbean island). Complete clinical histories and physical examinations, including an ear-nose-throat (ENT) exam were done. There was a significant statistical difference in the upper and lower respiratory symptomatology and ENT findings between control and exposed children (p < 0.001). Control children gave no respiratory symptomatology in the 3 months prior to the study; their biopsies exhibited normal ciliated respiratory epithelium and were p53-negative. SWMMC children complained of epistaxis, nasal obstruction. and crusting. Irregular areas of whitish-gray recessed mucosa over the inferior and middle turbinates were seen in 25% of SWMMC children, and their nasal biopsies displayed basal cell hyperplasia, decreased numbers of ciliated and goblet cells, neutrophilic epithelial infiltrates, squamous metaplasia. and mild dysplasia. Four of 21 SWMMC children with grossly abnormal mucosal changes exhibited strong transmural nuclear p53 staining in their nasal biopsies (p 0.005, odds ratio 26). In the context of lifetime exposures to toxic and potentially carcinogenic air pollutants, p53 nasal induction in children could potentially represent. a) a checkpoint response to toxic exposures, setting up a selective condition for p53 mutation, or b) a p53 mutation has already occurred as a result of such selection. Because the biological significance of p53 nuclear accumulation in the nasal biopsies of these children is not clear at this point, we strongly

Possible cause for altered spatial cognition of prepubescent rats exposed to chronic radiofrequency electromagnetic radiation.

Science.gov (United States)

Narayanan, Sareesh Naduvil; Kumar, Raju Suresh; Karun, Kalesh M; Nayak, Satheesha B; Bhat, P Gopalakrishna

2015-10-01

The effects of chronic and repeated radiofrequency electromagnetic radiation (RFEMR) exposure on spatial cognition and hippocampal architecture were investigated in prepubescent rats. Four weeks old male Wistar rats were exposed to RF-EMR (900 MHz; SAR-1.15 W/kg with peak power density of 146.60 μW/cm(2)) for 1 h/day, for 28 days. Followed by this, spatial cognition was evaluated by Morris water maze test. To evaluate the hippocampal morphology; H&E staining, cresyl violet staining, and Golgi-Cox staining were performed on hippocampal sections. CA3 pyramidal neuron morphology and surviving neuron count (in CA3 region) were studied using H&E and cresyl violet stained sections. Dendritic arborization pattern of CA3 pyramidal neuron was investigated by concentric circle method. Progressive learning abilities were found to be decreased in RF-EMR exposed rats. Memory retention test performed 24 h after the last training revealed minor spatial memory deficit in RF-EMR exposed group. However, RF-EMR exposed rats exhibited poor spatial memory retention when tested 48 h after the final trial. Hirano bodies and Granulovacuolar bodies were absent in the CA3 pyramidal neurons of different groups studied. Nevertheless, RF-EMR exposure affected the viable cell count in dorsal hippocampal CA3 region. RF-EMR exposure influenced dendritic arborization pattern of both apical and basal dendritic trees in RF-EMR exposed rats. Structural changes found in the hippocampus of RF-EMR exposed rats could be one of the possible reasons for altered cognition.

The corrosion behavior of steel exposed to a DC electric field in the simulated wet-dry cyclic environment

Energy Technology Data Exchange (ETDEWEB)

Dai, Nianwei [Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, Shanghai University of Electric Power, Shanghai 200090 (China); Department of Materials Science, Fudan University, Shanghai 200433 (China); Chen, Qimeng [Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, Shanghai University of Electric Power, Shanghai 200090 (China); Zhang, Junxi, E-mail: zhangjunxi@shiep.edu.cn [Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, Shanghai University of Electric Power, Shanghai 200090 (China); Zhang, Xin; Ni, Qingzhao [Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power, Shanghai University of Electric Power, Shanghai 200090 (China); Jiang, Yiming; Li, Jin [Department of Materials Science, Fudan University, Shanghai 200433 (China)

2017-05-01

The corrosion of steel exposed under a direct current (DC) electric field during simulated wet-dry cycles was investigated using weight gain, electrochemical tests, X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The results show that the steel exposed to a DC electric field exhibits a higher corrosion rate than those exposed under no DC electric field. The higher the DC electric field intensity, the higher the corrosion rate of steel. The XRD and SEM analyses indicate that more γ-FeOOH and cracks appear in the rust formed on steel exposed to the DC electric field. The porous γ-FeOOH, formation and expansion of cracks enhance the transfer of oxygen and corrosion products, thereby accelerating corrosion of steel exposed to DC electric field. - Highlights: • Effect of DC electric field on the corrosion of steel in wet/dry cycles was studied. • DC electric field accelerates the steel corrosion in wet/dry cyclic processes. • More γ-FeOOH is generated on the surface of steel exposed under a DC electric field. • More cracks appear in the rust formed on the steel exposed under a DC electric filed.

The corrosion behavior of steel exposed to a DC electric field in the simulated wet-dry cyclic environment

International Nuclear Information System (INIS)

Dai, Nianwei; Chen, Qimeng; Zhang, Junxi; Zhang, Xin; Ni, Qingzhao; Jiang, Yiming; Li, Jin

2017-01-01

The corrosion of steel exposed under a direct current (DC) electric field during simulated wet-dry cycles was investigated using weight gain, electrochemical tests, X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The results show that the steel exposed to a DC electric field exhibits a higher corrosion rate than those exposed under no DC electric field. The higher the DC electric field intensity, the higher the corrosion rate of steel. The XRD and SEM analyses indicate that more γ-FeOOH and cracks appear in the rust formed on steel exposed to the DC electric field. The porous γ-FeOOH, formation and expansion of cracks enhance the transfer of oxygen and corrosion products, thereby accelerating corrosion of steel exposed to DC electric field. - Highlights: • Effect of DC electric field on the corrosion of steel in wet/dry cycles was studied. • DC electric field accelerates the steel corrosion in wet/dry cyclic processes. • More γ-FeOOH is generated on the surface of steel exposed under a DC electric field. • More cracks appear in the rust formed on the steel exposed under a DC electric filed.

Overview of the ISS Radiation Environment Observed during the ESA EXPOSE-R2 Mission in 2014-2016

Science.gov (United States)

Dachev, T. P.; Bankov, N. G.; Tomov, B. T.; Matviichuk, Yu. N.; Dimitrov, Pl. G.; Häder, D.-P.; Horneck, G.

2017-11-01

The radiation risk radiometer-dosimeter (R3D)-R2 solid-state detector performed radiation measurements at the European Space Agency EXPOSE-R2 platform outside of the Russian "Zvezda" module at the International Space Station (ISS) from 24 October 2014 to 11 January 2016. The ISS orbital parameters were average altitude of 415 km and 51.6° inclination. We developed special software and used experimentally obtained formulas to determine the radiation flux-to-dose ratio from the R3DR2 Liulin-type deposited-energy spectrometer. We provide for the first time simultaneous, long-term estimates of radiation dose external to the ISS for four source categories: (i) galactic cosmic ray particles and their secondary products; (ii) protons in the South Atlantic Anomaly region of the inner radiation belt (IRB); (iii) relativistic electrons and/or bremsstrahlung in the outer radiation belt (ORB); and (iv) solar energetic particle (SEP) events. The latter category is new in this study. Additionally, in this study, secondary particles (SP) resulting from energetic particle interaction with the detector and nearby materials are identified. These are observed continuously at high latitudes. The detected SPs are identified using the same sorting requirements as SEP protons. The IRB protons provide the highest consistent hourly dose, while the ORB electrons and SEPs provide the most extreme hourly doses. SEPs were observed 11 times during the study interval. The R3DR2 data support calculation of average equivalent doses. The 30 day and 1 year average equivalent doses are much smaller than the skin and eyes doses recommendations by the National Council on Radiation Protection (Report 132), which provides radiation protection guidance for Low Earth Orbit.

Pulmonary hypertension and vascular remodeling in mice exposed to crystalline silica.

Science.gov (United States)

Zelko, Igor N; Zhu, Jianxin; Ritzenthaler, Jeffrey D; Roman, Jesse

2016-11-28

Occupational and environmental exposure to crystalline silica may lead to the development of silicosis, which is characterized by inflammation and progressive fibrosis. A substantial number of patients diagnosed with silicosis develop pulmonary hypertension. Pulmonary hypertension associated with silicosis and with related restrictive lung diseases significantly reduces survival in affected subjects. An animal model of silicosis has been described previously however, the magnitude of vascular remodeling and hemodynamic effects of inhaled silica are largely unknown. Considering the importance of such information, this study investigated whether mice exposed to silica develop pulmonary hypertension and vascular remodeling. C57BL6 mice were intratracheally injected with either saline or crystalline silica at doses 0.2 g/kg, 0.3 g/kg and 0.4 g/kg and then studied at day 28 post-exposure. Pulmonary hypertension was characterized by changes in right ventricular systolic pressure and lung histopathology. Mice exposed to saline showed normal lung histology and hemodynamic parameters while mice exposed to silica showed increased right ventricular systolic pressure and marked lung pathology characterized by a granulomatous inflammatory reaction and increased collagen deposition. Silica-exposed mice also showed signs of vascular remodeling with pulmonary artery muscularization, vascular occlusion, and medial thickening. The expression of pro-inflammatory genes such as TNF-α and MCP-1 was significantly upregulated as well as the expression of the pro-remodeling genes collagen type I, fibronectin and the metalloproteinases MMP-2 and TIMP-1. On the other hand, the expression of several vasculature specific genes involved in the regulation of endothelial function was significantly attenuated. We characterized a new animal model of pulmonary hypertension secondary to pulmonary fibrosis induced by crystalline silica. Our data suggest that silica promotes the damage of the

The developmental neurobehavioral effects of fenugreek seeds on prenatally exposed mice.

Science.gov (United States)

Khalki, Loubna; Bennis, Mohamed; Sokar, Zahra; Ba-M'hamed, Saâdia

2012-01-31

Fenugreek (Trigonella foenum graecum (L.)), is a medicinal plant whose seeds and leaves are widely used in Moroccan traditional medicine. Consumption of fenugreek seeds during pregnancy has been associated with a range of congenital malformations, including hydrocephalus, anencephaly and spina bifida. In previous work we have shown that exposure of pregnant mice to aqueous extract of fenugreek seeds (AEFS) leads to reduced litter size, intrauterine growth retardation, and malformations. However, there have been no studies to date of its longer-term neurobehavioral effects. We investigated these effects in prenatally exposed mice. Pregnant females were exposed to 0, 500 or 1000 mg/kg/day AEFS, by gavage, for the whole period of gestation. Pups body weight was measured at 1, 7, 14, 21 and 28 day of age. Behavior of progeny was evaluated three weeks after birth using the open field, the rotarod test and the continuous alternation task by the T-maze. At 28 postnatal day age, brain of progeny was removed and cut for histological evaluation. The progeny of exposed mice displayed reduced body weight at birth (1000 mg/kg group: 27%; 500 mg/kg group: 32%) and reduced brain weight (10% in both treated groups). Both males and females mice prenatally exposed to AEFS displayed a significant decrease in the locomotor activity, in the boli deposits during the open field test and in motor coordination. These results seem to show that exposure to AEFS induces a depressive effect in the offspring. Assessment on a continuous alternation T-maze test showed a significant reduction in successful spontaneous alternations in males and females but only in the 1000 mg/kg group. These results suggest that prenatal exposure of mice to high dose of fenugreek seeds causes growth retardation and altered neurobehavioral performance in the post-weaning period in both male and female. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Medical status of Marshallese accidentally exposed to 1954 Bravo fallout radiation: January 1980-December 1982

International Nuclear Information System (INIS)

Adams, W.H.; Harper, J.A.; Rittmaster, R.S.; Heotis, P.M.; Scott, W.A.

1984-01-01

This report updates, for 1980 through 1982, the results of continuing medical surveillance of a Marshallese population accidentally exposed to radioactive fallout in March 1954. The originally exposed Marshallese population comprised 64 persons on Rongelap Atoll who each received, on the average, an estimated 190 rads of absorbed external gamma radiation, 18 on Ailingnae Atoll who received 110 rads, and 159 on Utirik who received 11 rads. There were, in addition, 3 persons in utero on Rongelap, 1 person in utero on Ailingnae, and 8 persons in utero on Utirik who are considered exposed. The recipients of primary medical care include exposed and comparison populations as well as a rather large number of additional beneficiaries who are seen on a humanitarian basis of practical need and resource availability. In recent years, about 1400 people have been seen annually. This report, however, deals with four clearly defined groups: the remaining individuals who were exposed to radioactive fallout on Rongelap, Ailingnae, and Utirik in 1954 (including those in utero), and a comparison population of individuals from Rongelap who were unexposed. The number of persons now in each exposure category are 51, 12, 116, and 137, respectively. 100 references, 4 figures, 5 tables

Mercury-induced motor and sensory neurotoxicity: systematic review of workers currently exposed to mercury vapor.

Science.gov (United States)

Fields, Cheryl A; Borak, Jonathan; Louis, Elan D

2017-11-01

The neurotoxicity of elemental mercury (Hg 0 ) is well-recognized, but it is uncertain whether and for how long neurotoxicity persists; among studies that evaluated previously exposed workers, only one examined workers during and also years after exposure ceased. The aim of this review is to document the type, frequency, and dose-relatedness of objective neurological effects in currently exposed mercury workers and thereby provide first approximations of the effects one would have expected in previously exposed workers evaluated during exposure. We systematically reviewed studies of neurotoxicity in currently exposed mercury workers identified by searching MEDLINE (1950-2015), government reports, textbook chapters, and references cited therein; dental cohorts were not included. Outcomes on physical examination (PE), neurobehavioral (NB) tests, and electrophysiological studies were extracted and evaluated for consistency and dose-relatedness. Forty-five eligible studies were identified, comprising over 3000 workers chronically exposed to a range of Hg 0 concentrations (0.002-1.7 mg/m 3 ). Effects that demonstrated consistency across studies and increased frequency across urine mercury levels (200 μg/L, while NB testing is more appropriate for those with lower U Hg levels. They also provide benchmarks to which findings in workers with historical exposure can be compared.

Medical status of Marshallese accidentally exposed to 1954 Bravo fallout radiation: January 1980-December 1982

Energy Technology Data Exchange (ETDEWEB)

Adams, W.H.; Harper, J.A.; Rittmaster, R.S.; Heotis, P.M.; Scott, W.A.

1984-01-01

This report updates, for 1980 through 1982, the results of continuing medical surveillance of a Marshallese population accidentally exposed to radioactive fallout in March 1954. The originally exposed Marshallese population comprised 64 persons on Rongelap Atoll who each received, on the average, an estimated 190 rads of absorbed external gamma radiation, 18 on Ailingnae Atoll who received 110 rads, and 159 on Utirik who received 11 rads. There were, in addition, 3 persons in utero on Rongelap, 1 person in utero on Ailingnae, and 8 persons in utero on Utirik who are considered exposed. The recipients of primary medical care include exposed and comparison populations as well as a rather large number of additional beneficiaries who are seen on a humanitarian basis of practical need and resource availability. In recent years, about 1400 people have been seen annually. This report, however, deals with four clearly defined groups: the remaining individuals who were exposed to radioactive fallout on Rongelap, Ailingnae, and Utirik in 1954 (including those in utero), and a comparison population of individuals from Rongelap who were unexposed. The number of persons now in each exposure category are 51, 12, 116, and 137, respectively. 100 references, 4 figures, 5 tables. (ACR)

Spoiled Onions: Exposing Malicious Tor Exit Relays

OpenAIRE

Winter, Philipp; Lindskog, Stefan

2014-01-01

Several hundred Tor exit relays together push more than 1 GiB/s of network traffic. However, it is easy for exit relays to snoop and tamper with anonymised network traffic and as all relays are run by independent volunteers, not all of them are innocuous. In this paper, we seek to expose malicious exit relays and document their actions. First, we monitored the Tor network after developing a fast and modular exit relay scanner. We implemented several scanning modules for detecting common attac...

Potential Ecological Effects of Contaminants in the Exposed Par Pond Sediments

International Nuclear Information System (INIS)

Paller, M.H.; Wike, L.D.

1996-08-01

Sediment and small mammal samples were collected from the exposed sediments of Par Pond in early 1995, shortly before the reservoir was refilled after a 4-year drawdown. Sampling was confined to elevations between 58 and 61 meters (190 and 200 feet) above mean sea level, which includes the sediments likely to be exposed if the Par Pond water level is permitted to fluctuate naturally. Both soil and small mammal samples were analyzed for a number of radionuclides and metals. Some of the soil samples were also analyzed for organic contaminants. The objective of the study was to determine if contaminant levels in the Par Pond sediments were high enough to cause deleterious ecological effects

Serum TSH, thyroglobulin, and thyroid disorders in atomic bomb survivors exposed in youth: a study 30 years after exposure

International Nuclear Information System (INIS)

Morimoto, Isao; Yoshimoto, Yasuhiko; Sato, Kenshi; Hamilton, H.B.; Kawamoto, Sadahisa; Izumi, Motomori; Nagataki, Shigenobu.

1986-08-01

A study of individuals in Hiroshima and Nagasaki who were under 20 years of age at the time of atomic bomb exposure and who had been exposed to 100+ rad was conducted to determine the frequency of thyroid disorders as well as the levels of serum thyroid stimulating hormone (TSH), antithyroglobulin antibody, and thyroglobulin (TG), 30 years after exposure. Thyroid disorders were detected in 56 of the 477 subjects of the 100+ rad exposed group and in 39 of the 501 subjects of the 0 rad exposed group, the prevalence being significantly higher in the former group (X 2 = 3.872, P = 0.049). This increased prevalence of thyroid disorders in the 100+ rad exposed group was due to the increased occurrence of thyroid cancer and nontoxic uninodular goiter. Thyroid cancer was found in eight exposed individuals, all of whom belonged to the 100+ rad group; statistically, the prevalence was significantly higher (X 2 = 7.919, P = 0.005). Nontoxic uninodular goiter was observed in 13 cases of the 100+ rad exposed group and 3 cases of the 0 rad exposed group, the prevalence in the 100+ rad exposed group being significantly higher (X 2 = 6.584, P = 0.010). In these cases no increase of serum TSH or TG levels was observed. Mean serum TSH levels in individuals without thyroid disorders were 1.64 ± 1.89 μU/ml (n = 421) in the 100+ rad exposed group and 1.54 ± 1.86 μU/ml (n = 462) in the 0 rad exposed group. Mean serum TG levels were 13.49 ± 13.88 ng/ml (n = 421) in the 100+ rad exposed group and 14.76 ± 15.69 ng/ml (n = 462) in the 0 rad exposed group. Thus, these differences between the two groups were not significant. Also, no significant differences were observed between the 100+ rad and 0 rad exposed groups in the mean serum TSH and TG levels of the subjects who had thyroid diseases but had not been treated for the diseases, and the subjects who had no thyroid diseases. (J.P.N.)

Psychological distress in young adults exposed to war-related trauma in childhood.

Science.gov (United States)

Llabre, Maria M; Hadi, Fawzyiah; La Greca, Annette M; Lai, Betty S

2015-01-01

We tested a conceptual model of the effect of war-trauma exposure in childhood on psychological distress in young adulthood. Participants included 151 urban Kuwaiti children (51% female; M age = 10.62 years) exposed to the 1990-1991 Gulf crisis (assessed in 1993); participants also included 140 parents (81% female; M age mothers = 36.50 years; M age fathers = 41 years). In 2003, 120 participants were reassessed as young adults (50% female; M age = 21.19 years). The conceptual model was evaluated with structural equations. War-trauma exposure was associated with psychological distress in children and parents, but parents reported larger effects than children. Parents' psychological distress did not contribute to children's psychological distress. Children's psychological distress did not dissipate over time. Social support may function as a potential mediator of the effect of war-trauma exposure on psychological distress. Findings support the importance of early detection and treatment of children exposed to war trauma. Findings also implicate social support as a factor to consider in clinical interventions for children exposed to war trauma.

Relationship between arsenic and selenium in workers occupationally exposed to inorganic arsenic.

Science.gov (United States)

Janasik, Beata; Zawisza, Anna; Malachowska, Beata; Fendler, Wojciech; Stanislawska, Magdalena; Kuras, Renata; Wasowicz, Wojciech

2017-07-01

The interaction between arsenic (As) and selenium (Se) has been one of the most extensively studied. The antagonism between As and Se suggests that low Se status plays an important role in aggravating arsenic toxicity in diseases development. The objective of this study was to assess the Se contents in biological samples of inorganic As exposed workers (n=61) and in non-exposed subjects (n=52). Median (Me) total arsenic concentration in urine of exposed workers was 21.83μg/g creat. (interquartile range (IQR) 15.49-39.77) and was significantly higher than in the control group - (Me 3.75μg/g creat. (IQR 2.52-9.26), piAs+MMA+DMA) was significantly associated with the high total selenium urine excretion (B=0.14 (95%CI (confidence interval) 0.05-0.23)). Combination of both arsenic and selenium status to assess the risk of arsenic-induced diseases requires more studies with regard to both the analysis of speciation, genetics and the influence of factors such as nutritional status. Copyright © 2017 Elsevier GmbH. All rights reserved.

Double Jeopardy: Hearing Loss and Tinnitus Among Noise-Exposed Workers.

Science.gov (United States)

Hong, OiSaeng; Chin, Dal Lae; Phelps, Stephanie; Joo, Yoonmee

2016-06-01

The purpose of this study was to determine the prevalence and characteristics of tinnitus and assess the relationship between tinnitus and hearing loss among firefighters and operating engineers, who are exposed to noise on-the-job. The study analyzed existing data from two different populations (154 firefighters and 769 operating engineers) who completed a survey and audiometric tests as part of a hearing loss prevention intervention study. Approximately 40% of both groups reported tinnitus; 34% of firefighters and 59% of operating engineers showed hearing loss at noise-sensitive frequencies (4 kHz and 6 kHz). Firefighters with high frequency hearing loss (odds ratio [OR] = 2.31; 95% confidence interval [CI] = [1.05, 5.11]) and those with perceived impaired hearing status (OR = 3.53; 95% CI = [1.27, 9.80]) were significantly more likely to report tinnitus. Similarly, operating engineers who had hearing loss at both low (OR = 2.10; 95% CI = [1.40, 3.15]) and high frequencies (OR = 2.00; 95% CI = [1.37, 2.90]), and perceived impaired hearing status (OR = 2.17; 95% CI = [1.55, 3.05]) were twice as likely to report tinnitus. This study demonstrated that tinnitus is a considerable problem for noise-exposed workers. Workers with hearing loss demonstrated significantly higher rates of tinnitus. Comprehensive workplace hearing conservation programs should include tinnitus management for noise-exposed workers, along with other key elements such as noise control and hearing protection. © 2016 The Author(s).

Unmet Health Care Needs among Children Exposed to Parental Incarceration.

Science.gov (United States)

Turney, Kristin

2017-05-01

Objectives The incarceration rate in the United States has increased rapidly since the mid-1970s and, accordingly, a large number of children are exposed to parental incarceration. Research finds that parental incarceration is associated with deleterious physical and mental health outcomes among children, but little is known about these children's health care access. Methods I used data from the 2011-2012 National Survey of Children's Health (N = 95,531), a population-based and nationally representative survey of non-institutionalized children ages 0-17 in the United States, to estimate the association between exposure to parental incarceration and children's unmet health care needs. Results In logistic regression models that adjust for an array of demographic and socioeconomic characteristics, children exposed to parental incarceration, compared to their counterparts, have 1.26 (95% CI 1.02-1.54) times the odds of having any unmet health care need. Analyses that disaggregate by type of unmet health care need (mental, dental, vision, mental health, or other) suggest this association is driven by a greater likelihood of unmet mental health care needs (OR 1.60; 95% CI 1.04-2.46). Conclusions Children exposed to parental incarceration, a vulnerable group especially at risk of physical and mental health problems, face challenges to health care access, especially mental health care access. Given that parental incarceration is concentrated among those children most in need of health care, parental incarceration may exacerbate existing inequalities in unmet health care needs.

Ethanol emission from loose corn silage and exposed silage particles

Science.gov (United States)

Hafner, Sasha D.; Montes, Felipe; Rotz, C. Alan; Mitloehner, Frank

2010-11-01

Silage on dairy farms has been identified as a major source of volatile organic compound (VOC) emissions. However, rates of VOC emission from silage are not accurately known. In this work, we measured ethanol (a dominant silage VOC) emission from loose corn silage and exposed corn silage particles using wind tunnel systems. Flux of ethanol was highest immediately after exposing loose silage samples to moving air (as high as 220 g m -2 h -1) and declined by as much as 76-fold over 12 h as ethanol was depleted from samples. Emission rate and cumulative 12 h emission increased with temperature, silage permeability, exposed surface area, and air velocity over silage samples. These responses suggest that VOC emission from silage on farms is sensitive to climate and management practices. Ethanol emission rates from loose silage were generally higher than previous estimates of total VOC emission rates from silage and mixed feed. For 15 cm deep loose samples, mean cumulative emission was as high as 170 g m -2 (80% of initial ethanol mass) after 12 h of exposure to an air velocity of 5 m s -1. Emission rates measured with an emission isolation flux chamber were lower than rates measured in a wind tunnel and in an open setting. Results show that the US EPA emission isolation flux chamber method is not appropriate for estimating VOC emission rates from silage in the field.

Reduced expression of PARK2 in manganese-exposed smelting workers.

Science.gov (United States)

Fan, Ximin; Luo, Ying; Fan, Qiyuan; Zheng, Wei

2017-09-01

Manganese (Mn) is widely used in modern industries. Occupational exposure to Mn is known to cause clinical syndromes similar, but not identical to, Parkinson's disease. This human cohort study was designed to investigate if workers exposed to Mn altered the PARK2 gene expression, leading to Mn-induced neurotoxicity. Workers (n=26) occupationally exposed to Mn were recruited from a Mn-iron (Fe) alloy smelter, and control workers (n=20) without Mn-exposure were from an Fe smelter from Zunyi City in China. Subjects were matched with socioeconomic status and background for environmental factors. Metal concentrations were determined by atomic absorption spectrophotometry (AAS). Total RNA from the blood samples was isolated and analyzed by RT-PCR to quantify PARK2. The data showed that Mn concentrations in plasma, red blood cell (RBC) and saliva, and the cumulative Mn-exposure were about 2.2, 2.0, 1.7 and 3.0 fold higher, respectively, in Mn-exposed workers than those in control subjects (pworkers was significantly decreased by 42% as compared to controls (p<0.01). Linear regression analysis further established that the expression of PARK2 mRNA was inversely correlated with Mn levels in plasma, RBC and saliva, as well as the cumulative Mn exposure (p<0.01). Taken together, it seems likely that Mn exposure among smelters may lead to a reduced expression of PARK2, which may partly explain the Mn-induced Parkinsonian disorder. Copyright © 2017 Elsevier B.V. All rights reserved.

What are the toxicological effects of mercury in Arctic biota?

DEFF Research Database (Denmark)

Dietz, Rune; Sonne, Christian; Basu, Niladri

2013-01-01

effects. Species whose concentrations exceed threshold values include the polar bears (Ursus maritimus), beluga whale (Delphinapterus leucas), pilot whale (Globicephala melas), hooded seal (Cystophora cristata), a few seabird species, and landlocked Arctic char (Salvelinus alpinus). Toothed whales appear...

Upgrade and Design of Coastal Structures Exposed to Climate Changes

DEFF Research Database (Denmark)

Nørgaard, Jørgen Quvang Harck

This thesis “Upgrade and Design of Coastal Structures Exposed to Climate Changes” evaluates the performance of existing types of structures when exposed to climate changes. This includes also the potential of using cost‐sharing multipurpose structures for protection against the effects of future...... climate changes. The thesis consists of three parts. The first part evaluates the performance of existing design formulae for estimation of wave actions on structures, especially in shallow water since these structures are most vulnerable to the rising sea water levels caused by climate changes. Existing...... of coastal protection structures, which are extended to a wider range of wave conditions, and which can be used to more accurately estimate the influence from climate changes. In the second part of the thesis, the extended and modified formulae are used in case studies to evaluate the influence from climate...

Upgrade and Design of Coastal Structures Exposed to Climate Changes

DEFF Research Database (Denmark)

Nørgaard, Jørgen Quvang Harck

This thesis "Upgrade and Design of Coastal Structures Exposed to Climate Changes" evaluates the performance of existing types of structures when exposed to climate changes. This includes also the potential of using cost‐sharing multipurpose structures for protection against the effects of future...... climate changes. The thesis consists of three parts. The first part evaluates the performance of existing design formulae for estimation of wave actions on structures, especially in shallow water since these structures are most vulnerable to the rising sea water levels caused by climate changes. Existing...... of coastal protection structures, which are extended to a wider range of wave conditions, and which can be used to more accurately estimate the influence from climate changes. In the second part of the thesis, the extended and modified formulae are used in case studies to evaluate the influence from climate...

Contamination of persons occupationally exposed to natural radioactivity in a coal fired power plant

International Nuclear Information System (INIS)

Bauman, A.; Horvat, D.

1980-01-01

Contamination of occupationally exposed subjects with natural radioactivity in a coal fired power plant at levels of 500 mrem/year was detected. The level of 210 Pb in urine varied from 2.29-14.47 pCi/l. These values were arrived at after subtracting a blank value of 1.05 pCi 210 Pb obtained from a control group. Structural chromosomal aberrations, completely missing in the control group, were detected in the exposed subjects. Approximately 6-10% of the metaphases of occupationally exposed subjects were found to have aberrations which were probably radiation induced. These included symmetrical and asymmetrical exchanges and numerical aberrations. In the control aroup aberrations were found in 1.4-4% of the metaphases, but these were only deletions. (H.K.)

Metallothionein response in earthworms Lampito mauritii (Kinberg) exposed to fly ash

Energy Technology Data Exchange (ETDEWEB)

Maity, S.; Hattacharya, S.; Chaudhury, S. [Visva Bharati, Santini Ketan (India)

2009-10-15

Among pollutants, the coal fly ash occupies a significant position in industrial wastes. The fly ash matrix is a complex mixture of various organic (polyhalogenated compounds) and inorganic (Si, Al, Fe, As, Cd, Bi, Hg, etc.) chemicals. The application of fly ash for agricultural purposes and as landfills may lead to the contamination of the land with some of the toxic chemical compounds present in fly ash. Thus prior to the application of fly ash for developmental activities, it requires bio-monitoring and risk characterization. In order to achieve this objective adult Lampito mauritii were exposed to different proportions of fly ash in soil for 30 d and the concentrations of metallothionein in earthworm were assessed. The results revealed that up to 50% of fly ash amendment does not apparently harm the earthworm in respect of their survival and growth. A significant increase in tissue metallothionein level was recorded in L mauritii exposed to fly ash amended soil without tissue metal accumulation indicating that metallothionein is involved in scavenging of free radicals and reactive oxygen species metabolites. It is concluded that this biochemical response observed in L mauritii exposed to fly ash amended soil could be used in ecotoxicological field monitoring.

Response of solvent-exposed printers and unexposed controls to six-hour toluene exposure

DEFF Research Database (Denmark)

Bælum, Jesper; Andersen, I B; Lundqvist, G R

1985-01-01

of intoxication, and irritation of the eyes, nose and throat. Furthermore, the subjects exposed to toluene showed decreased manual dexterity, decreased color discrimination, and decreased accuracy in visual perception. There was no significant difference in the effects of toluene on printers compared to those......The acute effects of toluene were studied in 43 male printers and 43 control subjects matched according to sex, age, educational level, and smoking habits. The mean age of the subjects was 36 (range 29-50) years. The printers had been exposed to solvents for 9 to 25 years during employment at flexo...... and rotogravure printing plants, while the controls had no history of solvent exposure. Each subject was exposed once in a climate chamber to either 100 ppm of toluene or clean air for 6.5 h preceded by a 1-h acclimatization period. The effects of toluene were measured from subjective votes with linear analogue...

Environmental Monitoring Of Microbiological Laboratory: Expose Plate Method

International Nuclear Information System (INIS)

Yahaya Talib; Othman Mahmud; Noraisyah Mohd Yusof; Asmah Mohibat; Muhamad Syazwan Zulkifli

2013-01-01

Monitoring of microorganism is important and conducted regularly on environment of microbiological laboratory at Medical Technology Division. Its objective is to ensure the quality of working environment is maintained according to microbial contamination, consequently to assure the quality of microbiological tests. This paper presents report of environmental monitoring since year 2007. The test involved was bacterial colony counts after the growth media was exposed to air at identified location. (author)

Coupled external fixator and skin flap transposition for treatment of exposed and nonunion bone.

Science.gov (United States)

Zhao, Yong-gang; Ding, Jing; Wang, Neng

2011-02-01

To discuss the effect of coupled external fixator and skin flap transposition on exposed and nonunion bones. The data of 12 cases of infected nonunion and exposed bone following open fracture treated in our hospital during the period of March 1998 to June 2008 were analysed. There were 10 male patients, 2 female patients, whose age were between 19-52 years and averaged 28 years. There were 10 tibial fractures and 2 femoral fractures. The course of diseases lasted for 12-39 months with the mean period of 19 months. All the cases were treated by the coupled external fixator and skin flap transposition. Primary healing were achieved in 10 cases and delayed healing in 2 cases in whom the tibia was exposed due to soft tissue defect and hence local flap transposition was performed. All the 12 cases had bony union within 6-12 months after operation with the average time of 8 months. They were followed up for 1-3 years and all fractures healed up with good function and no infection recurrence. The coupled external fixator and skin flap transposition therapy have shown optimal effects on treating infected, exposed and nonunion bones.

Are Canadian youth still exposed to second-hand smoke in homes and in cars?

Science.gov (United States)

Barisic, A; Leatherdale, S T; Burkhalter, R; Ahmed, R

2014-07-01

The objective of this manuscript is to examine the prevalence of youth exposed to second-hand smoke (SHS) in homes and cars, changes in SHS exposure over time, and factors associated with beliefs youth hold regarding SHS exposure among a nationally representative sample of Canadian youth. Descriptive analysis of SHS exposure in homes and cars was conducted using data from the Canadian Youth Smoking Survey (2004, 2006 and 2008). Logistic regression was conducted to examine factors associated with beliefs youth had about SHS exposure in 2008. In 2008, 21.5% of youth reported being exposed to SHS in their home on a daily or almost daily basis, while 27.3% reported being exposed to SHS while riding in a car at least once in the previous week. Between 2004 and 2008, the prevalence of daily SHS exposure in the home and cars decreased by 4.7% and 18.0% respectively. Despite reductions in SHS exposure over time, a substantial number of Canadian youth continue to be exposed to SHS in homes and cars. Further effort is required to implement and evaluate policies designed to protect youth from SHS.

Adaptive response of Chironomus riparius populations exposed to uranium contaminated sediments during consecutive generations

International Nuclear Information System (INIS)

Dias, V.

2010-01-01

The intensity of selection on populations caused by polluted environment often exceeds which is caused by an unpolluted environment. Therefore, micro evolution can occur in response to this anthropic-directional force over a short period. In this context, this thesis focused on studying phenotypic changes in Chironomus riparius populations exposed during several consecutive generations to uranium-contaminated sediments. In laboratory-controlled conditions experiments were conducted with same origin populations exposed to a range of uranium concentration inducing toxic effects. Over eight-generations of exposure, life-history traits measures revealed micro evolution in exposed populations, including increase of adult reproductive success. Other experiments (acute toxicity test, common garden experiment) performed in parallel enabled to link these micro evolution with a tolerance induction, as a consequence of genetic adaptation. Nonetheless this adaptation also induced cost in terms of fitness and genetic diversity for pre-exposed populations. These results lead to the hypothesis of a selection by uranium that acted sequentially on populations. They also underline the need to better-understand the adaptive mechanisms to better assess the ecological consequences of chronic exposure of populations to a pollutant. (author)

Analyses of Concrete Structures Exposed to Fire

DEFF Research Database (Denmark)

Hertz, Kristian

The text book contains the data and methods necessary for fire safety design of concrete constructions. The methods relate to standard fire as well as to any time of any other fire course.Material data are presented for concretes exposed to fire, and calculation methods are given for the ultimate...... bending capacity of beams and slabs, the ultimate shear capacity of beams, for the instability of columns and walls and for the deflection of prestressed and non-prestressed beams, slabs, walls and columns.All methods have been derived and compared to tests by Kristian Hertz....

NIR spectroscopy as a tool for discriminating between lichens exposed to air pollution.

Science.gov (United States)

Casale, Monica; Bagnasco, Lucia; Giordani, Paolo; Mariotti, Mauro Giorgio; Malaspina, Paola

2015-09-01

Lichens are used as biomonitors of air pollution because they are extremely sensitive to the presence of substances that alter atmospheric composition. Fifty-one thalli of two different varieties of Pseudevernia furfuracea (var. furfuracea and var. ceratea) were collected far from local sources of air pollution. Twenty-six of these thalli were then exposed to the air for one month in the industrial port of Genoa, which has high levels of environmental pollution. The possibility of using Near-infrared spectroscopy (NIRS) for generating a 'fingerprint' of lichens was investigated. Chemometric methods were successfully applied to discriminate between samples from polluted and non-polluted areas. In particular, Principal Component Analysis (PCA) was applied as a multivariate display method on the NIR spectra to visualise the data structure. This showed that the difference between samples of different varieties was not significant in comparison to the difference between samples exposed to different levels of environmental pollution. Then Linear Discriminant Analysis (LDA) was carried out to discriminate between lichens based on their exposure to pollutants. The distinction between control samples (not exposed) and samples exposed to the air in the industrial port of Genoa was evaluated. On average, 95.2% of samples were correctly classified, 93.0% of total internal prediction (5 cross-validation groups) and 100.0% of external prediction (on the test set) was achieved. Copyright © 2015 Elsevier Ltd. All rights reserved.

Vascular Hyperpermeability Response in Animals Systemically Exposed to Arsenic.

Science.gov (United States)

Chen, Shih-Chieh; Chang, Chao-Yuah; Lin, Ming-Lu

2018-01-01

The mechanisms underlying cardiovascular diseases induced by chronic exposure to arsenic remain unclarified. The objectives of this study were to investigate whether increased vascular leakage is induced by inflammatory mustard oil in mice systemically exposed to various doses of arsenic and whether an increased vascular leakage response is still present in arsenic-fed mice after arsenic discontinuation for 2 or 6 months. ICR mice were fed water or various doses of sodium arsenite (10, 15, or 20 mg/kg/day; 5 days/week) for 8 weeks. In separate experiments, the mice were treated with sodium arsenite (20 mg/kg) for 2 or 8 weeks, followed by arsenic discontinuation for 2 or 6 months. Vascular permeability to inflammatory mustard oil was quantified using Evans blue (EB) techniques. Both arsenic-exposed and water-fed (control) mice displayed similar basal levels of EB leakage in the ears brushed with mineral oil, a vehicle of mustard oil. The levels of EB leakage induced by mustard oil in the arsenic groups fed with sodium arsenite (10 or 15 mg/kg) were similar to those of water-fed mice. However, increased levels of EB leakage in response to mustard oil stimulation were significantly higher in mice treated with sodium arsenite (20 mg/kg; high dose) than in arsenic-fed (10 or 15 mg/kg; low and middle doses) or control mice. After arsenic discontinuation for 2 or 6 months, mustard oil-induced vascular EB leakage in arsenic-fed (20 mg/kg) mice was similar to that in control mice. Dramatic increases in mustard oil-induced vascular leakage were only present in mice systemically exposed to the high arsenic dose, indicating the synergistic effects of the high arsenic dose and mustard oil.

Effects of volcanic deposit disaggregation on exposed water composition

Science.gov (United States)

Back, W. E.; Genareau, K. D.

2016-12-01

Explosive volcanic eruptions produce a variety of hazards. Pyroclastic material can be introduced to water through ash fallout, pyroclastic flows entering water bodies, and/or lahars. Remobilization of tephras can occur soon after eruption or centuries later, introducing additional pyroclastic material into the environment. Introduction of pyroclastic material may alter the dissolved element concentration and pH of exposed waters, potentially impacting drinking water supplies, agriculture, and ecology. This study focuses on the long-term impacts of volcanic deposits on water composition due to the mechanical breakup of volcanic deposits over time. Preliminary work has shown that mechanical milling of volcanic deposits will cause significant increases in dissolved element concentrations, conductivity, and pH of aqueous solutions. Pyroclastic material from seven eruptions sites was collected, mechanically milled to produce grain sizes Soufriere Hills, Ruapehu), mafic (Lathrop Wells) and ultramafic (mantle xenoliths) volcanic deposits. Lathrop Wells has an average bulk concentration of 49.15 wt.% SiO2, 6.11 wt. % MgO, and 8.39 wt. % CaO and produces leachate concentrations of 85.69 mg/kg for Ca and 37.22 mg/kg for Mg. Taupo and Valles Caldera samples have a bulk concentration of 72.9 wt.% SiO2, 0.59 wt. % MgO, and 1.48 wt. % CaO, and produces leachate concentrations of 4.08 mg/kg for Ca and 1.56 mg/kg for Mg. Similar testing will be conducted on the intermediate and ultramafic samples to test the hypothesis that bulk magma composition and mineralogy will directly relate to the increased dissolved element concentration of exposed waters. The measured effects on aqueous solutions will aid in evaluation of impacts to marine and freshwater systems exposed to volcanic deposits.

Heart rate variability in workers chronically exposed to lead.

Science.gov (United States)

Gajek, Jacek; Zyśko, Dorota; Chlebda, Ewa

2004-07-01

Lead is a strong neurotoxin. The effects of lead on the activity of the autonomic nervous system, assessed by the use of heart rate variability (HRV) analysis, have not yet been established. To assess the effects of occupational chronic lead exposure on the autonomic nervous system activity. The study group consisted of 22 copper foundry workers (mean age 41.8+/-8.7 years) who had elevated parameters of lead overload and were admitted to the hospital for chelate therapy. The control group consisted of 13 age-matched healthy males. Lead concentration was measured with the use of atomic absorption spectrophotometry, and concentration of free protoporphyrins in erythrocytes (FEP) using a fluorometric method. Each patient underwent 24-hour ambulatory ECG monitoring, and standard short-term as well as long-term HRV parameters were obtained. There were no significant differences between patients and controls in HRV parameters. In the control group, HRV parameters correlated with age. In patients, a significant negative correlation between lead concentration and some short-term HRV parameters calculated during the night was found: SDNN (r=-0.48, p<0.05), TP (r=-0.48, p<0.01) and LF (r=-0.48, p<0.01). In patients, a negative correlation between lead concentration and HFnight/HFday index was found (r=-0.47 p<0.01), whereas in controls this correlation was positive (r=0.66 p<0.05). Overall HRV indices are similar in subjects exposed to lead and in healthy controls. A decrease in the physiological elevation of HF values during the night, together with an increase in lead blood concentration and lack of relationship between age and HRV parameters in workers chronically exposed to lead may suggest disturbances of the autonomic system. In subjects not exposed to lead a decrease in heart rate with an increase in FEP concentration was observed.

The fate of chromosomal aberrations in 137Cs-exposed individuals in the Goiania radiation accident

International Nuclear Information System (INIS)

Ramalho, A.T.; Nascimento, A.C.

1991-01-01

Following the Goiania radiation accident, lymphocytes from 110 exposed or potentially exposed individuals were analyzed for the frequencies of chromosomal aberrations (dicentrics and centric rings) to estimate absorbed radiation dose. Dose estimates for 21 subjects exceeded 1.0 Gy, and for eight subjects they exceeded 4.0 Gy. Four of the subjects died. After the emergency period, a cytogenetic follow-up of 10 of the highest exposed patients was started. The results suggest that the average disappearance half-time of lymphocytes containing dicentric and centric rings was 130 d, which is shorter than the usually accepted value of 3 y reported in the literature

Attenuation of the cortisol response to stress in female rainbow trout chronically exposed to dietary selenomethionine

International Nuclear Information System (INIS)

Wiseman, Steve; Thomas, Jith K.; McPhee, Landon; Hursky, Olesya; Raine, Jason C.; Pietrock, Michael; Giesy, John P.; Hecker, Markus; Janz, David M.

2011-01-01

Highlights: Trout exposed to Se-Met had greater concentration of cortisol compared to controls. Transcript abundance of mc2r was greater in trout exposed to Se-Met. Trout exposed to Se-Met had a reduced cortisol response to a handling stressor. Cortisone concentration was greater in Se-Met exposed trout post-handling stressor. - Abstract: Selenomethionine (Se-Met) is the major dietary form of selenium (Se). While Se is a required nutrient, it can also influence the physiological stress response because it stimulates greater concentrations of cortisol in blood plasma of exposed fish. However, little is known about the effects of exposure to Se on the ability to cope with a secondary stressor. In the current study, female rainbow trout were exposed to an environmentally relevant dietary concentration (8.47 mg Se/kg dry mass (dm)) of Se-Met for 126 d, after which time fish were subjected to a 3-min handling stressor and sampled at 2 h and 24 h post-stressor exposure. Concentrations of cortisol, cortisone, glucose, and lactate in blood plasma and concentrations of glycogen and triglycerides in liver and muscle were determined. Abundances of transcripts of proteins involved in corticosteroidogenesis were determined using quantitative RT-PCR. Concentrations of cortisol were significantly greater in blood plasma of trout exposed to Se-Met, relative to control trout sampled prior to the handling stressor. A typical response of cortisol to the handling stressor was observed in the control trout. However, trout exposed to Se-Met were unable to mount a cortisol response to the handling stressor. Concentrations of cortisone, the inactive metabolite of cortisol, were significantly greater following the handling stressor in trout exposed to Se-Met. In trout exposed to Se-Met, transcript abundance of melanocortin 2 receptor (mc2r) and peripheral benzodiazepine receptor (pbr) were greater, which is consistent with the conclusion that synthesis of cortisol was greater. However

Attenuation of the cortisol response to stress in female rainbow trout chronically exposed to dietary selenomethionine

Energy Technology Data Exchange (ETDEWEB)

Wiseman, Steve, E-mail: steve.wiseman@usask.ca [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Thomas, Jith K.; McPhee, Landon; Hursky, Olesya; Raine, Jason C. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Pietrock, Michael [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Giesy, John P. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong (Hong Kong); School of Biological Sciences, University of Hong Kong, Hong Kong (Hong Kong); Department of Zoology, Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824 (United States); State Key Laboratory of Pollution Control and Resource Reuse and School of the Environment, Nanjing University, Nanjing (China); Hecker, Markus [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); School of Environment and Sustainability, University of Saskatchewan, Saskatoon, SK, S7N 5CB (Canada); Janz, David M. [Toxicology Centre, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada); Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK, S7N 5B3 (Canada)

2011-10-15

Highlights: Trout exposed to Se-Met had greater concentration of cortisol compared to controls. Transcript abundance of mc2r was greater in trout exposed to Se-Met. Trout exposed to Se-Met had a reduced cortisol response to a handling stressor. Cortisone concentration was greater in Se-Met exposed trout post-handling stressor. - Abstract: Selenomethionine (Se-Met) is the major dietary form of selenium (Se). While Se is a required nutrient, it can also influence the physiological stress response because it stimulates greater concentrations of cortisol in blood plasma of exposed fish. However, little is known about the effects of exposure to Se on the ability to cope with a secondary stressor. In the current study, female rainbow trout were exposed to an environmentally relevant dietary concentration (8.47 mg Se/kg dry mass (dm)) of Se-Met for 126 d, after which time fish were subjected to a 3-min handling stressor and sampled at 2 h and 24 h post-stressor exposure. Concentrations of cortisol, cortisone, glucose, and lactate in blood plasma and concentrations of glycogen and triglycerides in liver and muscle were determined. Abundances of transcripts of proteins involved in corticosteroidogenesis were determined using quantitative RT-PCR. Concentrations of cortisol were significantly greater in blood plasma of trout exposed to Se-Met, relative to control trout sampled prior to the handling stressor. A typical response of cortisol to the handling stressor was observed in the control trout. However, trout exposed to Se-Met were unable to mount a cortisol response to the handling stressor. Concentrations of cortisone, the inactive metabolite of cortisol, were significantly greater following the handling stressor in trout exposed to Se-Met. In trout exposed to Se-Met, transcript abundance of melanocortin 2 receptor (mc2r) and peripheral benzodiazepine receptor (pbr) were greater, which is consistent with the conclusion that synthesis of cortisol was greater. However

Differential Adjustment Among Rural Adolescents Exposed to Family Violence

Science.gov (United States)

Sianko, Natallia; Hedge, Jasmine M.; McDonell, James R.

2016-01-01

This study examines differences in psychological adjustment in a sample of rural adolescents who have been exposed to family violence. Self-report questionnaires were administered to 580 adolescents and their primary caregivers. The results revealed that over two thirds of the study participants (68.8%) had been exposed to violence in their families. As hypothesized, cluster analysis identified several profiles among adolescents, distinguished by their psychological and emotional functioning: well adjusted (46.2%), moderately adjusted (44.3%), and struggling (9.5%). Discriminant function analysis confirmed the groupings and revealed that family functioning was among the most influential factors explaining adjustment differences. Multivariate analyses of variance (MANOVAs) further showed that adolescents from each of the three adjustment profiles reported significantly different levels of family social support, parental involvement, and perceived neighborhood safety. Overall, the results confirm heterogeneity of adolescent adaptation in the aftermath of family violence and provide insights into family and neighborhood factors that account for variability in adolescents’ reactions to violence. Implications for future research and practical interventions are discussed. PMID:27106255

Error-related negativities during spelling judgments expose orthographic knowledge.

Science.gov (United States)

Harris, Lindsay N; Perfetti, Charles A; Rickles, Benjamin

2014-02-01

In two experiments, we demonstrate that error-related negativities (ERNs) recorded during spelling decisions can expose individual differences in lexical knowledge. The first experiment found that the ERN was elicited during spelling decisions and that its magnitude was correlated with independent measures of subjects' spelling knowledge. In the second experiment, we manipulated the phonology of misspelled stimuli and observed that ERN magnitudes were larger when misspelled words altered the phonology of their correctly spelled counterparts than when they preserved it. Thus, when an error is made in a decision about spelling, the brain processes indexed by the ERN reflect both phonological and orthographic input to the decision process. In both experiments, ERN effect sizes were correlated with assessments of lexical knowledge and reading, including offline spelling ability and spelling-mediated vocabulary knowledge. These results affirm the interdependent nature of orthographic, semantic, and phonological knowledge components while showing that spelling knowledge uniquely influences the ERN during spelling decisions. Finally, the study demonstrates the value of ERNs in exposing individual differences in lexical knowledge. Copyright © 2013 Elsevier Ltd. All rights reserved.

Differential Adjustment Among Rural Adolescents Exposed to Family Violence.

Science.gov (United States)

Sianko, Natallia; Hedge, Jasmine M; McDonell, James R

2016-04-22

This study examines differences in psychological adjustment in a sample of rural adolescents who have been exposed to family violence. Self-report questionnaires were administered to 580 adolescents and their primary caregivers. The results revealed that over two thirds of the study participants (68.8%) had been exposed to violence in their families. As hypothesized, cluster analysis identified several profiles among adolescents, distinguished by their psychological and emotional functioning: well adjusted (46.2%), moderately adjusted (44.3%), and struggling (9.5%). Discriminant function analysis confirmed the groupings and revealed that family functioning was among the most influential factors explaining adjustment differences. Multivariate analyses of variance (MANOVAs) further showed that adolescents from each of the three adjustment profiles reported significantly different levels of family social support, parental involvement, and perceived neighborhood safety. Overall, the results confirm heterogeneity of adolescent adaptation in the aftermath of family violence and provide insights into family and neighborhood factors that account for variability in adolescents' reactions to violence. Implications for future research and practical interventions are discussed. © The Author(s) 2016.

RESPONSE OF TOMATO PLANTS EXPOSED TO TREATMENT WITH NANOPARTICLES

Directory of Open Access Journals (Sweden)

Tommaso Giordani

2012-07-01

Full Text Available In this work the response of Tomato plants cv. Micro-Tom to nanoparticles (NPs treatment was investigated. Tomato seedlings were grown in hydroponic condition and NPs treatments were carried out by adding Fe3O4 or TiO2 NPs to nutrient solution. At the end of treatments, NPs root uptake and tissue deposition were investigated using Environmental Scanning Electron Microscope, equipped with energy dispersive spectroscopy for chemical identification. At morphological level, one week after the beginning of NP treatment, seedlings grown with high concentration of TiO2 NPs showed an abnormal proliferation of root hairs, as compared to the control seedlings and to the seedlings exposed to Fe3O4 NPs, Shoot morphology did not differ in tomato seedlings grown under different conditions and no symptoms of toxicity were observed in NP-treated plants. In order to analyse genetic effects of NPs treatments, RNA transcription was studied in roots of NP-exposed and control plants by Illumina RNA sequencing, evidencing the induction of transposable elements.

Cytogenetic diagnostic of 3 populations of occupationally exposed personnel

International Nuclear Information System (INIS)

Guerrero C, C.; Arceo M, C.

2013-10-01

In the year 2000 the first service of biological dosimetry was requested to the Instituto Nacional de Investigaciones Nucleares (ININ), and until the year 2012 have been assisted 52 cases approximately. Most of the cases correspond to workers dedicated to the industrial radiography, followed by the occupationally exposed personnel either in the hospital area or health services and the minority corresponds to individuals linked to research institutions. The incident with more serious consequences to the individual happened to workers that ingested I-131 in the year 2003. Using the biological dosimetry to estimate exposure dose by damage in the lymphocyte chromosomes of each worker has been possible to establish the exposure dose in each one of them, or also to discard the supposed exposure. The dosimetry demonstrates to be an useful tool for situations with exposure suspicion, for example when the reading of thermoluminescent dosimeter of a occupationally exposed personnel does not correspond to the event, or when the personnel forgets to carry his dosimeter, the exposure dose can be determined. (Author)

The Immune System of HIV-Exposed Uninfected Infants.

Science.gov (United States)

Abu-Raya, Bahaa; Kollmann, Tobias R; Marchant, Arnaud; MacGillivray, Duncan M

2016-01-01

Infants born to human immunodeficiency virus (HIV) infected women are HIV-exposed but the majority remains uninfected [i.e., HIV-exposed uninfected (HEU)]. HEU infants suffer greater morbidity and mortality from infections compared to HIV-unexposed (HU) peers. The reason(s) for these worse outcomes are uncertain, but could be related to an altered immune system state. This review comprehensively summarizes the current literature investigating the adaptive and innate immune system of HEU infants. HEU infants have altered cell-mediated immunity, including impaired T-cell maturation with documented hypo- as well as hyper-responsiveness to T-cell activation. And although prevaccination vaccine-specific antibody levels are often lower in HEU than HU, most HEU infants mount adequate humoral immune response following primary vaccination with diphtheria toxoid, haemophilus influenzae type b, whole cell pertussis, measles, hepatitis B, tetanus toxoid, and pneumococcal conjugate vaccines. However, HEU infants are often found to have lower absolute neutrophil counts as compared to HU infants. On the other hand, an increase of innate immune cytokine production and expression of co-stimulatory markers has been noted in HEU infants, but this increase appears to be restricted to the first few weeks of life. The immune system of HEU children beyond infancy remains largely unexplored.

Chromosomal aberrations in subjects exposed to ionizing radiation

International Nuclear Information System (INIS)

Jovicic, D.; Milacic, S.; Kovacevic, R.; Tanaskovic, I.

2006-01-01

Occupational exposure is particularly delicate because of chronic exposure to low doses of ionizing radiation and its cumulative effect, where it is important to consider the biological response of body to given conditions of exposure. The objective of this study was the observation of the recovery of the DNA damages in subjects working in the radiation area in two different intervals.Group I, consisting of 30 subjects, was exposed to ionizing radiation and unstable chromosomal aberrations were identified. Group II included the same, re-examined subjects (30) 9 months later. It was verified that 5 (16.67%) subjects still had unstable chromosomal aberrations, although they had been excluded from radiation area Controls groups (C) consisted of 64 subjects that were not exposed to mutagenic agents.The comparison of the control group with the two studied groups revealed the reduction of the unstable aberrations (p<0.05). The total effective doses, which increased with the years spent in radiation area, reflected the yield of chromosomal aberrations. The presence of chromosomal aberrations in some subjects, after the exclusion from the ionising radiation exposure, suggests that the time needed for the recovery of the DNA damages is different, which indicates the individual differences in radiosensitivity as well as different of the reparatory cellular response. (author)

Environmental impact of heavy metals on the blood cells in professionally exposed workers

OpenAIRE

Velickova, Nevenka

2017-01-01

Aims of the study is to explain and research the effects of the heavy metals (lead, zinc and cadmium) on erythrocytes and leukocytes in miners with different work experience or exposure. The results and conclusions are made based on a three-year period of continuous testing on 120 miners, as professionally exposed workers. We confirmed that the miners long been professionally exposed to heavy metals, in the blood have an increased content of heavy metals (lead, zinc and cadmium) and they ha...

Factors protecting against the development of adjustment difficulties in young adults exposed to childhood sexual abuse.

Science.gov (United States)

Lynskey, M T; Fergusson, D M

1997-12-01

The aims of this study were to identify the factors which discriminated young people exposed to childhood sexual abuse (CSA) who developed psychiatric disorder or adjustment difficulties in young adulthood from those young people exposed to CSA who did not develop psychiatric disorder or adjustment difficulties by age 18. Data were gathered on a birth cohort of 1,025 New Zealand children studied from birth to the age of 18 on (a) exposure to CSA; (b) patterns of psychiatric disorder and adjustment difficulties at age 18 years; (c) factors that may have influenced responses to CSA including characteristics of the abuse, parental bonding, parental characteristics, and adolescent peer affiliations. Just over 10% of the cohort reported CSA. Those reporting CSA were at increased risks of a range of difficulties at age 18 (depression, anxiety, conduct disorder, alcohol abuse/dependence, other substance abuse/dependence, post sexual abuse trauma, attempted suicide). However, not all of those exposed to CSA developed difficulties and approximately a quarter of those exposed to CSA did not meet criteria for any adjustment difficulty. Further analysis suggested that the extent of adjustment difficulties in those exposed to CSA was influenced by two additional factors: (a) the extent of affiliations with delinquent or substance using peers in adolescence; and (b) the extent of paternal care or support in childhood. The findings of this study suggest that while young people exposed to CSA are at increased risks of psychiatric disorder and adjustment difficulties in young adulthood, not all individuals exposed to CSA will develop adjustment difficulties. Important factors protecting against the development of adjustment difficulties in young people experiencing CSA appear to be the nature and quality of peer and family relationships.

Alterations in thyroid hormone status in Greenland sledge dogs exposed to whale blubber contaminated with organohalogen compounds

DEFF Research Database (Denmark)

Kirkegaard, Maja; Sonne, Christian; Dietz, Rune

2011-01-01

As a model of high trophic level carnivores, sledge dogs were fed from 2 to 18 months of age with minke whale blubber containing organohalogen compounds (OHC) corresponding to 128µg PCB/day. Controls were fed uncontaminated porcine fat. Thyroid hormone levels were assessed in 7 exposed and 7...... control sister bitches (sampled at age 6-18 months) and 4 exposed and 4 control pups, fed the same diet as their mothers (sampled age 3-12 months). Lower free and total T3 and T4 were seen in exposed vs. control bitches beyond 10 months of age, and total T3 was lower through 3-12 months of age in exposed...

Socio-psycho-historical observation on the twin. Sampling methods and case study of the atomic bomb exposed twins

Energy Technology Data Exchange (ETDEWEB)

Watanabe, S; Satow, Y; Ueoka, Hiroshi; Munaka, M; Kurihara, M [Hiroshima Univ. (Japan). Research Inst. for Nuclear Medicine and Biology

1980-07-01

The so-called ''twin control study'', mainly on the monozygotic twins one of which was A-bomb exposed and the other was non-exposed were carried out. Sampling was conducted utilizing the materials as follows: 1) The survey on casualities of A-bomb exposed families in Hiroshima which was undertaken in 1946. 2) The survey of A-bomb survivors in 1965. 3) A-bomb exposed family survey conducted between 1973 to 1975. 4) Investigations of A-bomb victims exposed in the proximal areas from the hypocenter. From the above mentioned materials 470 pairs were selected, of which 220 were exposed. Among them 172 pairs were twins of the same sex. Female and male pair were also employed. In one case they were exposed, while the others were nonexposed. Two pairs were examined under the following methods: 1) Depth interview to ascertain familial casualities with reference to the family life cycle. 2) Socio-historical research. 3) Motoaki's Jinkaku Shindan Kensa (Modified Rorschach test by H. Motoaki), and T.A.T. test. Results obtained were summarized as follows: 1) Both pairs of twins were of similar appearance and personality traits, and had a strong feeling of companionship for each other. 2) In family relationships, the persons studied were very conscious of the role expectations of elder and younger siblings in the twin pairs. 3) Through depth interviews and projective tests, A-bomb exposed pairs still showed deep psychological stresses, resulting from the A-bomb disaster. 4) Both among the exposed twins and within the nonexposed control group twin siblings had a close feeling of companionship for each other. However, nonexposed twins could not understand the psychological experience of twins who had been subjected to the atomic disaster.

Mechanical and Microstructural Evaluations of Lightweight Aggregate Geopolymer Concrete before and after Exposed to Elevated Temperatures.

Science.gov (United States)

Abdulkareem, Omar A; Abdullah, Mohd Mustafa Al Bakri; Hussin, Kamarudin; Ismail, Khairul Nizar; Binhussain, Mohammed

2013-10-09

This paper presents the mechanical and microstructural characteristics of a lightweight aggregate geopolymer concrete (LWAGC) synthesized by the alkali-activation of a fly ash source (FA) before and after being exposed to elevated temperatures, ranging from 100 to 800 °C. The results show that the LWAGC unexposed to the elevated temperatures possesses a good strength-to-weight ratio compared with other LWAGCs available in the published literature. The unexposed LWAGC also shows an excellent strength development versus aging times, up to 365 days. For the exposed LWAGC to the elevated temperatures of 100 to 800 °C, the results illustrate that the concretes gain compressive strength after being exposed to elevated temperatures of 100, 200 and 300 °C. Afterward, the strength of the LWAGC started to deteriorate and decrease after being exposed to elevated temperatures of 400 °C, and up to 800 °C. Based on the mechanical strength results of the exposed LWAGCs to elevated temperatures of 100 °C to 800 °C, the relationship between the exposure temperature and the obtained residual compressive strength is statistically analyzed and achieved. In addition, the microstructure investigation of the unexposed LWAGC shows a good bonding between aggregate and mortar at the interface transition zone (ITZ). However, this bonding is subjected to deterioration as the LWAGC is exposed to elevated temperatures of 400, 600 and 800 °C by increasing the microcrack content and swelling of the unreacted silicates.

Risk and resilience trajectories in war-exposed children across the first decade of life.

Science.gov (United States)

Halevi, Galit; Djalovski, Amir; Vengrober, Adva; Feldman, Ruth

2016-10-01

Although the effects of early-onset trauma on susceptibility to psychopathology are well-acknowledged, no study to date has followed risk and resilience trajectories in war-exposed young children over lengthy periods and charted predictors of individual pathways. In this prospective longitudinal study, we followed 232 children, including 148 exposed to repeated wartime trauma and 84 controls, at three time points: early childhood (1.5-5 years), middle childhood (5-8 years), and late childhood (9-11 years). Children were diagnosed at each time point and four trajectories defined: children exhibiting no pathology at any time point, those displaying early pathology that later remitted, those showing initial resilience followed by late pathology, and children presenting chronic pathology across the entire first decade. Maternal behavioral containment during trauma evocation and child social engagement during free play were observed in early childhood and maternal emotional distress self-reported across time. War-exposed children showed significantly higher rates of psychopathology, with 81% exhibiting pathology at some point during childhood. In middle childhood, exposed children displayed more posttraumatic stress disorders (PTSD), anxiety disorders, and attention-deficit/hyperactivity disorders (ADHD), and in late childhood more PTSD, conduct/oppositional defiant disorders, and ADHD. War-exposed children had more comorbid psychopathologies and number of comorbidities increased with age. Notably, war-exposure increased prevalence of chronic pathology by 24-fold. Maternal factors, including mother's uncontained style and emotional distress, increased risk for early and chronic psychopathology, whereas reduced child social engagement augmented risk for late pathology. Early-onset chronic stress does not heal naturally, and its effects appear to exacerbate over time, with trauma-exposed children presenting a more comorbid, chronic, and externalizing profile as they

Diagnostic tests in Raynaud's phenomena in workers exposed to vibration: a comparative study

DEFF Research Database (Denmark)

Olsen, N

1988-01-01

Four objective tests to evaluate Raynaud's phenomena (RP) in workers exposed to handarm vibrations were applied on 23 exposed men with RP (vibration induced white finger 18, primary Raynaud's phenomenon 5), 56 exposed men without RP, and 15 male controls. Finger systolic blood pressure was measured...... greater than 0.20). The results indicate that a finger colour test may be as valuable as a FSP(0) test for diagnostic purposes. FSP(A) only indicates if a cold response is exaggerated and does not diagnose RP. The pressure measurements may further be of guidance in evaluating preventive measures...... by a cuff and strain gauge technique after combined body cooling and finger cooling during five minute ischaemia to 30 degrees, 15 degrees, and 6 degrees C. An attack of RP was detected as a zero pressure, FSP(0) test, whereas a pressure, reduced to a value below the normal 95% confidence limit at 6 degrees...

Sperm quality and DNA damage in men from Jilin Province, China, who are occupationally exposed to ionizing radiation.

Science.gov (United States)

Zhou, D D; Hao, J L; Guo, K M; Lu, C W; Liu, X D

2016-03-22

Long-term radiation exposure affects human health. Ionizing radiation has long been known to raise the risk of cancer. In addition to high doses of radiation, low-dose ionizing radiation might increase the risk of cardiovascular disease, lens opacity, and some other non-cancerous diseases. Low- and high-dose exposures to ionizing radiation elicit different signaling events at the molecular level, and may involve different response mechanisms. The health risks arising from exposure to low doses of ionizing radiation should be re-evaluated. Health workers exposed to ionizing radiation experience low-dose radiation and have an increased risk of hematological malignancies. Reproductive function is sensitive to changes in the physical environment, including ionizing radiation. However, data is scarce regarding the association between occupational radiation exposure and risk to human fertility. Sperm DNA integrity is a functional parameter of male fertility evaluation. Hence, we aimed to report sperm quality and DNA damage in men from Jilin Province, China, who were occupationally exposed to ionizing radiation. Sperm motility and normal morphology were significantly lower in the exposed compared with the non-exposed men. There was no statistically significant difference in sperm concentration between exposed and non-exposed men. The sperm DNA fragmentation index was significantly higher in the exposed than the non-exposed men. Chronic long-term exposure to low doses of ionizing radiation could affect sperm motility, normal morphology, and the sperm DNA fragmentation index in the Chinese population. Sperm quality and DNA integrity are functional parameters that could be used to evaluate occupational exposure to ionizing radiation.

Entanglement witnesses arising from exposed positive linear maps

OpenAIRE

Ha, Kil-Chan; Kye, Seung-Hyeok

2011-01-01

We consider entanglement witnesses arising from positive linear maps which generate exposed extremal rays. We show that every entanglement can be detected by one of these witnesses, and this witness detects a unique set of entanglement among those. Therefore, they provide a minimal set of witnesses to detect all entanglement in a sense. Furthermore, if those maps are indecomposable then they detect large classes of entanglement with positive partial transposes which have nonempty relative int...

Rich Representations with Exposed Semantics for Deep Visual Reasoning

Science.gov (United States)

2016-06-01

of a relationship between visual recognition, associative processing, and episodic memory and provides important clues into the neural mechanism...provides critical evidence of a relationship between visual recognition, associative processing, and episodic memory and provides important clues into...From - To) ;run.- ~01~ Final!Technical 4. TITLE AND SUBTITLE Sa. CONTRACT NUMBER Rich Representations with Exposed Semantics for Deep Visual

Chest X ray examination of workers exposed to pneumoconiosis risk

International Nuclear Information System (INIS)

Indovina, P.L.; Reggiani, A.; Calicchia, A.; Nicolosi, A.

1986-01-01

Chest X-ray examination of workers exposed to pneumoconiosis risk: critical analysis of legal and radiation protection aspects. Chest X-ray examination is one of the most common radiological examinations practised in Italy. According to Presidential Decree 1124/65, workers exposed to risk of asbestosis and silicosis must undergo a chest radiography once a year, on occasion of the periodic medical examination. Basic requirements aimed at the radiation protection of the patient must therefore be complied with, and optimization of the chest radiography execution procedures is required. This paper illustrates the results obtained with the implementation of the NEXT programme in Italy for this kind of X-ray examination. The main objective of the NEXT programme is the optimization of radiological techniques. On the basis of the most recent publications in the field of radiation protection, a critical analysis is made of the laws in force in Italy

Mental health interventions for children exposed to disasters and terrorism.

Science.gov (United States)

Pfefferbaum, Betty; Newman, Elana; Nelson, Summer D

2014-02-01

The purpose of this review is to describe interventions used with children who are exposed to disasters and terrorism and to present information about the potential benefits of these interventions. A literature search conducted in January 2013 using relevant databases and literature known to the authors that was not generated by the search yielded a total of 85 studies appropriate for review. Intervention approaches used with children exposed to disasters and terrorism included preparedness interventions, psychological first aid, psychological debriefing, psychoeducation, cognitive behavioral techniques, exposure and narrative techniques, eye movement desensitization and reprocessing, and traumatic grief interventions. The investigation of these interventions is complex, and studies varied in methodological rigor (e.g., sample size, the use of control groups, outcomes measured). Given the limitations in the currently available empirical information, this review integrates the literature, draws tentative conclusions about the current state of knowledge, and suggests future directions for study.

Cell growth, intracellular calcium concentration and metabolic cooperation measured in cells exposed to 50 Hz electromagnetic fields

International Nuclear Information System (INIS)

Skauli, K.S.

1996-08-01

Colony-forming efficiency, DNA/protein and DNA/cell were measured in cells exposed to magnetic fields of 0.2 and 1 mT at a frequency of 50 Hz. Intracellular calcium concentrations were measured in cells exposed to 0.3 and 1 mT at 50 Hz. Metabolic cooperation was measured in cells exposed to 1 mT at 50 Hz. No significant effects of the fields were observed. 20 refs., 10 figs

Negative pressure wound therapy for the treatment of infected wounds with exposed knee joint after patellar fracture.

Science.gov (United States)

Lee, Sang Yang; Niikura, Takahiro; Miwa, Masahiko; Sakai, Yoshitada; Oe, Keisuke; Fukazawa, Takahiro; Kawakami, Yohei; Kurosaka, Masahiro

2011-06-14

Treatment of soft tissue defects with exposed bones and joints, resulting from trauma, infection, and surgical complications, represents a major challenge. The introduction of negative pressure wound therapy has changed many wound management practices. Negative pressure wound therapy has recently been used in the orthopedic field for management of traumatic or open wounds with exposed bone, nerve, tendon, and orthopedic implants. This article describes a case of a patient with a large soft tissue defect and exposed knee joint, in which negative pressure wound therapy markedly improved wound healing. A 50-year-old man presented with an ulceration of his left knee with exposed joint, caused by severe wound infections after open reduction and internal fixation of a patellar fracture. After 20 days of negative pressure wound therapy, a granulated wound bed covered the exposed bones and joint.To our knowledge, this is the first report of negative pressure wound therapy used in a patient with a large soft tissue defect with exposed knee joint. Despite the chronic wound secondary to infection, healing was achieved through the use of the negative pressure wound therapy, thus promoting granulation tissue formation and closing the joint. We suggest negative pressure wound therapy as an alternative option for patients with lower limb wounds containing exposed bones and joints when free flap transfer is contraindicated. Our result added to the growing evidence that negative pressure wound therapy is a useful adjunctive treatment for open wounds around the knee joint. Copyright 2011, SLACK Incorporated.

Oxidative damage of DNA in subjects occupationally exposed to lead.

Science.gov (United States)

Pawlas, Natalia; Olewińska, Elżbieta; Markiewicz-Górka, Iwona; Kozłowska, Agnieszka; Januszewska, Lidia; Lundh, Thomas; Januszewska, Ewa; Pawlas, Krystyna

2017-09-01

Exposure to lead (Pb) in environmental and occupational settings continues to be a serious public health problem and may pose an elevated risk of genetic damage. The aim of this study was to assess the level of oxidative stress and DNA damage in subjects occupationally exposed to lead. We studied a population of 78 male workers exposed to lead in a lead and zinc smelter and battery recycling plant and 38 men from a control group. Blood lead levels were detected by graphite furnace atomic absorption spectrophotometry and plasma lead levels by inductively coupled plasma-mass spectrometry. The following assays were performed to assess the DNA damage and oxidative stress: comet assay, determination of 8-hydroxy-2'-deoxyguanosine (8-OHdG), lipid peroxidation and total antioxidant status (TAS). The mean concentration of lead in the blood of the exposed group was 392 ± 103 μg/L and was significantly higher than in the control group (30.3 ± 29.4 μg/L, p lead exposure [lead in blood, lead in plasma, zinc protoporphyrin (ZPP)] and urine concentration of 8-OHdG. The level of oxidative damage of DNA was positively correlated with the level of lipid peroxidation (TBARS) and negatively with total anti-oxidative status (TAS). Our study suggests that occupational exposure causes an increase in oxidative damage to DNA, even in subjects with relatively short length of service (average length of about 10 years). 8-OHdG concentration in the urine proved to be a sensitive and non-invasive marker of lead induced genotoxic damage.

Improving antenatal risk assessment in women exposed to high risks.

Science.gov (United States)

Perry, Natasha; Newman, Louise K; Hunter, Mick; Dunlop, Adrian

2015-01-01

Antenatal substance use and related psychosocial risk factors are known to increase the likelihood of child protection involvement; less is known about the predictive nature of maternal reflective functioning (RF) in this population. This preliminary study assessed psychosocial and psychological risk factors for a group of substance dependent women exposed to high risks in pregnancy, and their impact on child protection involvement. Pregnant women on opiate substitution treatment (n = 11) and a comparison group (n = 15) were recruited during their third trimester to complete measures of RF (Pregnancy Interview), childhood trauma, mental health and psychosocial assessments. At postnatal follow-up, RF was reassessed (Parent Development Interview - Revised Short Version) and mother-infant dyads were videotaped to assess emotional availability (EA). Child protection services were contacted to determine if any concerns had been raised for infant safety. Significant between-group differences were observed for demographics, psychosocial factors, trauma and mental health symptoms. Unexpectedly, no significant differences were found for RF or EA between groups. Eight women in the 'exposed to high risks' group became involved with child protection services. Reflective functioning was not significantly associated with psychosocial risk factors, and therefore did not mediate the outcome of child protection involvement. Women 'exposed to high risks' were equally able to generate a model of their own and their infants' mental states and should not be seen within a deficit perspective. Further research is required to better understand the range of risk factors that predict child protection involvement in high risk groups. © The Author(s) 2013.

Expose : procedure and results of the joint experiment verification tests

Science.gov (United States)

Panitz, C.; Rettberg, P.; Horneck, G.; Rabbow, E.; Baglioni, P.

The International Space Station will carry the EXPOSE facility accommodated at the universal workplace URM-D located outside the Russian Service Module. The launch will be affected in 2005 and it is planned to stay in space for 1.5 years. The tray like structure will accomodate 2 chemical and 6 biological PI-experiments or experiment systems of the ROSE (Response of Organisms to Space Environment) consortium. EXPOSE will support long-term in situ studies of microbes in artificial meteorites, as well as of microbial communities from special ecological niches, such as endolithic and evaporitic ecosystems. The either vented or sealed experiment pockets will be covered by an optical filter system to control intensity and spectral range of solar UV irradiation. Control of sun exposure will be achieved by the use of individual shutters. To test the compatibility of the different biological systems and their adaptation to the opportunities and constraints of space conditions a profound ground support program has been developed. The procedure and first results of this joint Experiment Verification Tests (EVT) will be presented. The results will be essential for the success of the EXPOSE mission and have been done in parallel with the development and construction of the final hardware design of the facility. The results of the mission will contribute to the understanding of the organic chemistry processes in space, the biological adaptation strategies to extreme conditions, e.g. on early Earth and Mars, and the distribution of life beyond its planet of origin.

Abnormal emotional learning in a rat model of autism exposed to valproic acid in utero

Directory of Open Access Journals (Sweden)

Anwesha eBanerjee

2014-11-01

Full Text Available Autism Spectrum Disorders (ASD are complex neurodevelopmental disorders characterized by repetitive behavior and impaired social communication and interactions. Apart from these core symptoms, a significant number of ASD individuals display higher levels of anxiety and some ASD individuals exhibit impaired emotional learning. We therefore sought to further examine anxiety and emotional learning in an environmentally induced animal model of ASD that utilizes the administration of the known teratogen, valproic acid (VPA during gestation. Specifically we exposed dams to one of two different doses of VPA (500 and 600 mg/kg or vehicle on day 12.5 of gestation and examined the resultant progeny. Our data indicate that animals exposed to VPA in utero exhibit enhanced anxiety in the open field test and normal object recognition memory compared to control animals. Animals exposed to 500 mg/kg of VPA displayed normal acquisition of auditory fear conditioning, and exhibited reduced extinction of fear memory and normal litter survival rates as compared to control animals. We observed that animals exposed to 600 mg/kg of VPA exhibited a significant reduction in the acquisition of fear conditioning, a significant reduction in social interaction and a significant reduction in litter survival rates as compared to control animals. VPA (600 mg/kg exposed animals exhibited similar shock sensitivity and hearing as compared to control animals indicating the fear conditioning deficit observed in these animals was not likely due to sensory deficits, but rather due to deficits in learning or memory retrieval. In conclusion, considering that progeny from dams exposed to rather similar doses of VPA exhibit striking differences in emotional learning, the VPA model may serve as a useful tool to explore the molecular and cellular mechanisms that contribute to not only ASD, but also emotional learning.

Incidence of micronuclei in human peripheral blood lymphocytes exposed to modulated and unmodulated 2450 MHz radiofrequency fields.

Science.gov (United States)

Vijayalaxmi; Reddy, Abhishek B; McKenzie, Raymond J; McIntosh, Robert L; Prihoda, Thomas J; Wood, Andrew W

2013-10-01

Peripheral blood samples from four healthy volunteers were collected and aliquots were exposed in vitro for 2 h to either (i) modulated (wideband code division multiple access, WCDMA) or unmodulated continuous wave (CW) 2450 MHz radiofrequency (RF) fields at an average specific absorption rate of 10.9 W/kg or (ii) sham-exposed. Aliquots of the same samples that were exposed in vitro to an acute dose of 1.5 Gy ionizing gamma-radiation (GR) were used as positive controls. Half of the aliquots were treated with melatonin (Mel) to investigate if such treatment offers protection to the cells from the genetic damage, if any, induced by RF and GR. The cells in all samples were cultured for 72 h and the lymphocytes were examined to determine the extent of genetic damage assessed from the incidence of micronuclei (MN). The results indicated the following: (i) the incidence of MN was similar in incubator controls, and those exposed to RF/sham and Mel alone; (ii) there were no significant differences between WCDMA and CW RF exposures; (iii) positive control cells exposed to GR alone exhibited significantly increased MN; and (iv) Mel treatment had no effect on cells exposed to RF and sham, while such treatment significantly reduced the frequency of MN in GR-exposed cells. Copyright © 2013 Wiley Periodicals, Inc.

Comparison of urinary thallium levels in non-occupationally exposed people and workers.

Science.gov (United States)

Staff, James F; Cotton, Richard J; Warren, Nicholas D; Morton, Jackie

2014-04-01

To determine a reference background urinary thallium level; to compare urinary thallium data from workers to this background level; to investigate factors affecting these levels and whether creatinine correction is appropriate. Urine samples from non-occupationally exposed people (n = 273, from 113 individuals) and workers (n = 896, from 447 individuals) were analysed for thallium by ICP-MS. A reference background level was calculated, defined as the 95th percentile value of a non-occupationally exposed population. Worker data were divided into two subsets: thallium workers (those who work directly with thallium or its compounds) and general workers; and compared to the background level. Bayesian linear mixed effects modelling was used to investigate factors affecting urinary thallium concentration and the efficacy of creatinine correction for the determination of urinary thallium. The reference background urinary thallium level is 0.27 μmol/mol creatinine (creatinine-corrected) or 0.40 μg/l (uncorrected). Median values were 0.11 μmol/mol creatinine or 0.17 μg/l for non-occupationally exposed people, 0.12 μmol/mol creatinine or 0.20 μg/l for general workers and 0.19 μmol/mol creatinine or 0.41 μg/l for thallium workers. Variation was lower in creatinine-corrected models. Nine per cent of samples from general workers and 39 % of samples from thallium workers exceeded the creatinine-corrected background level. By 2010, 90 % of all workers had urinary thallium levels below the 95th percentile reference background level. Urinary thallium concentrations were higher in thallium workers than non-occupationally exposed people and general workers. Creatinine correction is appropriate.

The exposed breast

International Nuclear Information System (INIS)

Ingman, Wendy

2014-01-01

The skin and lungs are two tissues that are frequently bombarded with cancer-initiating factors, such as ultraviolet rays from the sun and smoke and pollutants in the air we breathe. Yet breast cancer is the most common type of cancer in Australian women, affecting one in eight before the age of 85. It is more common than skin melanoma and lung cancer. Why, then, does the breast so commonly get cancer when it is not a tissue that is particularly exposed to the environmental agents that increase cancer risk in other major organs? Is there something unique about this tissue that makes it particularly susceptible? The breast undergoes cellular changes over the course of the monthly menstrual cycle, and and these changes affect cancer susceptibility. Rising levels of the hormones oestrogen and progesterone occur immediately after the egg is released from the ovary, and these hormones cause the breast cells to divide and change to accommodate further development if pregnancy occurs. If the woman becomes pregnant, the cells in the breast continue to develop and become the milk-producing structures required to feed a newborn baby. But if pregnancy does not occur there is a drop in progesterone, which triggers the death of the newly developed breast cells. This occurs at the same time women have their period. Then the cycle starts again, and continues every month until menopause, unless the woman becomes pregnant.

Exposing the faults

International Nuclear Information System (INIS)

Richardson, P.J.

1989-01-01

UK NIREX, the body with responsibility for finding an acceptable strategy for deposition of radioactive waste has given the impression throughout its recent public consultation that the problem of nuclear waste is one of public and political acceptability, rather than one of a technical nature. However the results of the consultation process show that it has no mandate from the British public to develop a single, national, deep repository for the burial of radioactive waste. There is considerable opposition to this method of managing radioactive waste and suspicion of the claims by NIREX concerning the supposed integrity and safety of this deep burial option. This report gives substance to those suspicions and details the significant areas of uncertainty in the concept of effective geological containment of hazardous radioactive elements, which remain dangerous for tens of thousands of years. Because the science of geology is essentially retrospective rather than predictive, NIREX's plans for a single, national, deep 'repository' depend heavily upon a wide range of assumptions about the geological and hydrogeological regimes in certain areas of the UK. This report demonstrates that these assumptions are based on a limited understanding of UK geology and on unvalidated and simplistic theoretical models of geological processes, the performance of which can never be directly tested over the long time-scales involved. NIREX's proposals offer no guarantees for the safe and effective containment of radioactivity. They are deeply flawed. This report exposes the faults. (author)

Evaluation of cytogenetic damage in nuclear medicine personnel occupationally exposed to low-level ionising radiation

International Nuclear Information System (INIS)

Garaj-Vrhovac, V.; Kopjar, N.; Poropat, M.

2005-01-01

Despite intensive research over the last few decades, there still remains considerable uncertainty as to the genetic impact of ionising radiation on human populations, particularly at low levels. The aim of this study was to provide data on genetic hazards associated with occupational exposure to low doses of ionising radiation in nuclear medicine departments. The assessment of DNA damage in peripheral blood lymphocytes of medical staff was performed using the chromosome aberration (CA) test. Exposed subjects showed significantly higher frequencies of CA than controls. There were significant inter-individual differences in DNA damage within the exposed population, indicating differences in genome sensitivity. Age and gender were not confounding factors, while smoking enhanced the levels of DNA damage only in control subjects. The present study suggests that chronic exposure to low doses of ionising radiation in nuclear medicine departments causes genotoxic damage. Therefore, to avoid potential genotoxic effects, the exposed medical personnel should minimise radiation exposure wherever possible. Our results also point to the significance of biological indicators providing information about the actual risk to the radiation exposed individuals.(author)

Donation to disaster relief campaigns: underlying social cognitive factors exposed

NARCIS (Netherlands)

Oosterhof, Liesbeth; Heuvelman, A.; Peters, O.

2009-01-01

number of very serious natural disasters have put an enormous pressure on relief organizations in the last few years. The present study exposes underlying social cognitive factors for donation to relief campaigns. A causal model was constructed, based on social cognitive theory, research on

A cytogenetic study on persons exposed to 241Am-Be neutron source

International Nuclear Information System (INIS)

Bai Yushu; Zhang Xiuxia; Guan Shurong; Xie Feng; Lu Meiying

1988-01-01

An 241 Am-Be neutron source of 120 millicrocurie was stolen by a boy on April the 3rd, 1982. He brought it to his home. The neutron source was broken and the radioactive substance contaminated the whole family. He and his other family members did not leave the contaminated environment for 70 days. There were altogether 14 persons exposed to the radioactive substances. Chromosome aberrations of peripheral blood lymphocytes of six exposed cases were analysed on an early day of June 1982. The exposure doses were estimated by the frequency of chromosome aberration. Biological dose absorbed by the boy who stole the source was about 96 ∼ 128 mGy (physical dose about 120 mGy), the others were about 10 ∼ 30 mGy (physical dose about 10 ∼ 30 mGy). The results indicated that biological dose were quite approximate to the physical doses. One and half years after the accident, the analysis of stable chromosome aberrations for 14 exposed persons showed that the frequencies of chromosome aberrations of the irradiated individuals were still higher than those of the controls. The differences between them are very significant

Maternal Characteristics of Women Exposed to Hypnotic Benzodiazepine Receptor Agonist during Pregnancy

Directory of Open Access Journals (Sweden)

Bjarke Askaa

2014-01-01

Full Text Available Background. There is little knowledge regarding the characteristics of women treated with hypnotic benzodiazepine receptor agonists (HBRAs during pregnancy. In this large Danish cohort study, we characterize women exposed to HBRA during pregnancy. We determined changes in prevalence of HBRA use from 1997 to 2010 and exposure to HBRAs in relation to pregnancy. Methods. We performed a retrospective cohort study including 911,017 pregnant women in the period from 1997 to 2010. Information was retrieved from The Danish Birth Registry and The Registry of Medicinal Product Statistics to identify pregnant women redeeming a prescription of HBRAs. Results. We identified 2,552 women exposed to HBRAs during pregnancy, increasing from 0.18% in 1997 to 0.23% in 2010. Compared to unexposed women, exposed women were characterized by being older, with higher BMI, in their third or fourth parity, of lower income and education level, more frequently smokers, and more likely to be comedicated with antipsychotic, anxiolytic, or antidepressant drugs (P<0.0001. Conclusion. Women using HBRAs during their pregnancy differ from unexposed women in socioeconomic factors and were more likely to receive comedication. The consumption of HBRAs was reduced during pregnancy compared to before conception.

Neurocognitive, mental health, and glucose disorders in farmers exposed to organophosphorus pesticides.

Science.gov (United States)

Malekirad, Ali Akbar; Faghih, Mahya; Mirabdollahi, Mansuoreh; Kiani, Mahdi; Fathi, Arezoo; Abdollahi, Mohammad

2013-01-01

About 25 million agricultural workers in the developing world suffer from at least one episode of poisoning each year, mainly by anticholinesterase-like organophosphates (OPs). The objective of this cross-sectional study was to establish the OP toxicity in 187 occupationally exposed farmers in terms of neurocognitive impairment, mental health status, clinical symptoms, diabetes, and haematological factors. The exposed group was compared to 187 healthy age-, sex-, and education-matching controls. Neurocognitive impairment was measured using the Subjective Neurocognition Inventory (SNI) and mental health status using the General Health Questionnaire-28 (GHQ-28). The subjects were also tested for fasting blood glucose (FBG), blood urea nitrogen (BUN), cholesterol (CL), triglycerides (TG), creatinine, oral glucose tolerance test (GTT), high-density lipoprotein (HDL), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP). The exposed farmers showed higher FBG (peczema, saliva secretion, fatigue, headache, sweating, abdominal pain, nausea, superior distal muscle weakness, inferior distal muscle weakness, inferior proximal muscle weakness, breath muscle weakness, hand tingling, foot tingling, epiphoria, polyuria, miosis, dyspnoea, bradycardia, and rhinorrhoea, which all significantly correlated with the number of working years. These findings indicate that farmers who work with OPs are prone to neuropsychological disorders and diabetes.

Turmeric extract inhibits apoptosis of hippocampal neurons of trimethyltin-exposed rats.

Science.gov (United States)

Yuliani, S; Widyarini, S; Mustofa; Partadiredja, G

2017-01-01

The aim of the present study was to reveal the possible antiapoptotic effect of turmeric (Curcuma longa Linn.) on the hippocampal neurons of rats exposed to trimethyltin (TMT). Oxidative damage in the hippocampus can induce the apoptosis of neurons associated with the pathogenesis of dementiaMETHODS. The ethanolic turmeric extract and a citicoline (as positive control) solution were administered to the TMT-exposed rats for 28 days. The body weights of rats were recorded once a week. The hippocampal weights and imumunohistochemical expression of caspase 3 proteins in the CA1 and CA2-CA3 regions of the hippocampi were examined at the end of the experiment. Immunohistochemical analysis showed that the injection of TMT increased the expression of caspase 3 in the CA1 and CA2-CA3 regions of hippocampus. TMT also decreased the body and hippocampal weights. Furthermore, the administration of 200 mg/kg bw dose of turmeric extract decreased the caspase 3 expression in the CA2-CA3 pyramidal neurons but not in the CA1 neurons. It also prevented the decrease of the body and hippocampal weights. We suggest that the 200 mg/kg bw dose of turmeric extract may exert antiapoptotic effect on the hippocampal neurons of the TMT-exposed rats (Tab. 1, Fig. 3, Ref. 49).

Pulmonary function testing of animals chronically exposed to diluted diesel exhaust

Energy Technology Data Exchange (ETDEWEB)

Gross, K B

1981-04-01

The purpose of this work was to assess the potential effect that chronic inhalation of diesel exhaust may have on lung mechanics and lung volume. Noninvasive pulmonary function tests that produced data on lung air flows and volumes have been conducted repeatedly on 25 male Fischer-344 rats exposed to diesel exhaust at a particulate concentration of 1500 micrograms m-3, 20 h per day, 5 1/2 days per week, for 612 days. The same tests were conducted on 25 clean air control animals. When the data were normalized, the majority of tests did not reveal any significant deviation from the norm for the first year of exposure. In the second year, the functional residual capacity and its component volumes - expiratory reserve and residual volume, maximum expiratory flow at 40% of vital capacity, maximum expiratory flow at 20% of vital capacity and the forced expiratory volume in 0.1 s - were significantly greater in the diesel exposed animals. The data are inconsistent with known clinically significant adverse health effects. Although the lung volume changes in the diesel exposed animals could be indicative of emphysema or other forms of chronic obstructive lung disease, this interpretation is contradicted by the air flow data which suggest simultaneous lowering of the resistance of the smaller airways. The observations are not consistent with documented clinical lung disease in man.

Exosomes from asbestos-exposed cells modulate gene expression in mesothelial cells.

Science.gov (United States)

Munson, Phillip; Lam, Ying-Wai; Dragon, Julie; MacPherson, Maximilian; Shukla, Arti

2018-03-19

Asbestos exposure is a determinate cause of many diseases, such as mesothelioma, fibrosis, and lung cancer, and poses a major human health hazard. At this time, there are no identified biomarkers to demarcate asbestos exposure before the presentation of disease and symptoms, and there is only limited understanding of the underlying biology that governs asbestos-induced disease. In our study, we used exosomes, 30-140 nm extracellular vesicles, to gain insight into these knowledge gaps. As inhaled asbestos is first encountered by lung epithelial cells and macrophages, we hypothesize that asbestos-exposed cells secrete exosomes with signature proteomic cargo that can alter the gene expression of mesothelial cells, contributing to disease outcomes like mesothelioma. In the present study using lung epithelial cells (BEAS2B) and macrophages (THP-1), we first show that asbestos exposure causes changes in abundance of some proteins in the exosomes secreted from these cells. Furthermore, exposure of human mesothelial cells (HPM3) to these exosomes resulted in gene expression changes related to epithelial-to-mesenchymal transition and other cancer-related genes. This is the first report to indicate that asbestos-exposed cells secrete exosomes with differentially abundant proteins and that those exosomes have a gene-altering effect on mesothelial cells.-Munson, P., Lam, Y.-W., Dragon, J. MacPherson, M., Shukla, A. Exosomes from asbestos-exposed cells modulate gene expression in mesothelial cells.

[Quantitative analysis of urinary ethylene glycol in rats exposed to ethylene oxide].

Science.gov (United States)

Koga, M; Hori, H; Tanaka, I; Akiyama, T; Inoue, N

1985-03-01

A gas chromatographic method was used for determining ethylene glycol in urine. The analytical procedure is based on an azeotropic distillation and on esterification with n-butyl boronic acid. The linear calibration curve was obtained up to 500 micrograms/ml of ethylene glycol. The detection limit was estimated to be 10 micrograms/ml and relative standard deviation was 3.5% for 100 micrograms/ml of ethylene glycol. This method was applied to determine the urinary excretion of ethylene glycol in rats exposed to ethylene oxide at various concentrations (from 50 to 500 ppm). The excretion amounts of ethylene glycol were observed to be dependent on the concentration of ethylene oxide exposed.

Occupational health care of radiation exposed workers

International Nuclear Information System (INIS)

Abdul Rahim Rahman Hamzah

1995-01-01

The medical problems encountered by the earlier pioneer workers in radiation at the turn of the century are well known. In the 1928, the ICRP (International Committee for Radiological Protection) was instituted and the ALARA principle of radiation protection was evolved. Occupational health care is about maintaining the health and safety of workers in their workplaces. This involves using medical, nursing and engineering practices to achieve its objectives. In certain occupations, including those where workers are exposed to ionising radiation, some of these principles are enshrined in the legislation and would require statutory compliance. Occupational health care of radiation workers seek to prevent ill health arising from exposure to radiation by consolidating the benefits of exposures control and dosimetry. This is via health surveillance for spillages, contamination and exposures to unsealed sources of radiation. It is unlikely that can plan and hope to cater for a Chernobyl type of disaster. However, for the multitude of workers in industry exposed to radiation, control models are available. These are from the more in industrialize countries with a nuclear based energy industry, and where radioactive gadgetry are used in places ranging from factories and farms to construction sites. These models involve statutory requirements on the standard of work practices, assessment of fitness to work and the monitoring of both the worker and the workplace. A similar framework of activity is present in Malaysia. This will be further enhanced with the development of her general health and safety at work legislation. (author)

Ca2+ promoted the low transformation efficiency of plasmid DNA exposed to PAH contaminants.

Directory of Open Access Journals (Sweden)

Fuxing Kang

Full Text Available The effects of interactions between genetic materials and polycyclic aromatic hydrocarbons (PAHs on gene expression in the extracellular environment remain to be elucidated and little information is currently available on the effect of ionic strength on the transformation of plasmid DNA exposed to PAHs. Phenanthrene and pyrene were used as representative PAHs to evaluate the transformation of plasmid DNA after PAH exposure and to determine the role of Ca(2+ during the transformation. Plasmid DNA exposed to the test PAHs demonstrated low transformation efficiency. In the absence of PAHs, the transformation efficiency was 4.7 log units; however, the efficiency decreased to 3.72-3.14 log units with phenanthrene/pyrene exposures of 50 µg · L(-1. The addition of Ca(2+ enhanced the low transformation efficiency of DNA exposed to PAHs. Based on the co-sorption of Ca(2+ and phenanthrene/pyrene by DNA, we employed Fourier-transform infrared spectroscopy (FTIR, X-ray photoelectron spectroscopy (XPS, and mass spectrometry (MS to determine the mechanisms involved in PAH-induced DNA transformation. The observed low transformation efficiency of DNA exposed to either phenanthrene or pyrene can be attributed to a broken hydrogen bond in the double helix caused by planar PAHs. Added Ca(2+ formed strong electrovalent bonds with "-POO(--" groups in the DNA, weakening the interaction between PAHs and DNA based on weak molecular forces. This decreased the damage of PAHs to hydrogen bonds in double-stranded DNA by isolating DNA molecules from PAHs and consequently enhanced the transformation efficiency of DNA exposed to PAH contaminants. The findings provide insight into the effects of anthropogenic trace PAHs on DNA transfer in natural environments.

Inhibition of immune responses and related proteins in Rhamdia quelen exposed to diclofenac.

Science.gov (United States)

Ribas, João L C; Sherry, James P; Zampronio, Aleksander R; Silva de Assis, Helena C; Simmons, Denina B D

2017-08-01

Nonsteroidal anti-inflammatory drugs are among the most widely detected pharmaceuticals in surface water worldwide. The nonsteroidal anti-inflammatory drug diclofenac is used to treat many types of pain and inflammation. Diclofenac's potential to cause adverse effects in exposed wildlife is a growing concern. To evaluate the effects of waterborne diclofenac on the immune response in Rhamdia quelen (South American catfish), fish were exposed to 3 concentrations of diclofenac (0.2, 2.0, and 20.0 μg/L) for 14 d. Some of the exposed fish were also given an intraperitoneal injection on day 14 of 1 mg/kg of carrageenan to evaluate cell migration to the peritoneum. Total blood leukocyte count and carrageenan-induced leukocyte migration to the peritoneal cavity, particularly of polymorphonuclear cells, were significantly affected for all diclofenac exposure groups. Nitric oxide production was significantly reduced in the diclofenac-treated fish. Plasma and kidney proteins were analyzed by means of liquid chromatography-tandem mass spectrometry in a shotgun proteomic approach. In both plasma and kidney of diclofenac-exposed R. quelen, the expression of 20 proteins related to the inflammatory process, nitric oxide production, leukocyte migration, and the complement cascade was significantly altered. In addition, class I major histocompatibility complex was significantly decreased in plasma of diclofenac-treated fish. Thus, waterborne exposure to diclofenac could lead to suppression of the innate immune system in R. quelen. Environ Toxicol Chem 2017;36:2092-2107. © 2017 SETAC. © 2017 SETAC.