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Sample records for thunnus obesus lowe

  1. Discrimination of juvenile yellowfin (Thunnus albacares and bigeye (T. obesus Tunas using mitochondrial DNA control region and liver morphology.

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    Ivane R Pedrosa-Gerasmio

    Full Text Available Yellowfin tuna, Thunnus albacares (Bonnaterre, 1788 and bigeye tuna, Thunnus obesus (Lowe, 1839 are two of the most economically important tuna species in the world. However, identification of their juveniles, especially at sizes less than 40 cm, is very difficult, often leading to misidentification and miscalculation of their catch estimates. Here, we applied the mitochondrial DNA control region D-loop, a recently validated genetic marker used for identifying tuna species (Genus Thunnus, to discriminate juvenile tunas caught by purse seine and ringnet sets around fish aggregating devices (FADs off the Southern Iloilo Peninsula in Central Philippines. We checked individual identifications using the Neighbor-Joining Method and compared results with morphometric analyses and the liver phenotype. We tested 48 specimens ranging from 13 to 31 cm fork length. Morpho-meristic analyses suggested that 12 specimens (25% were bigeye tuna and 36 specimens (75% were yellowfin tuna. In contrast, the genetic and liver analyses both showed that 5 specimens (10% were bigeye tuna and 43 (90% yellowfin tuna. This suggests that misidentification can occur even with highly stringent morpho-meristic characters and that the mtDNA control region and liver phenotype are excellent markers to discriminate juveniles of yellowfin and bigeye tunas.

  2. Development of a qPCR Method for the Identification and Quantification of Two Closely Related Tuna Species, Bigeye Tuna (Thunnus obesus) and Yellowfin Tuna (Thunnus albacares), in Canned Tuna.

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    Bojolly, Daline; Doyen, Périne; Le Fur, Bruno; Christaki, Urania; Verrez-Bagnis, Véronique; Grard, Thierry

    2017-02-01

    Bigeye tuna (Thunnus obesus) and yellowfin tuna (Thunnus albacares) are among the most widely used tuna species for canning purposes. Not only substitution but also mixing of tuna species is prohibited by the European regulation for canned tuna products. However, as juveniles of bigeye and yellowfin tunas are very difficult to distinguish, unintentional substitutions may occur during the canning process. In this study, two mitochondrial markers from NADH dehydrogenase subunit 2 and cytochrome c oxidase subunit II genes were used to identify bigeye tuna and yellowfin tuna, respectively, utilizing TaqMan qPCR methodology. Two different qPCR-based methods were developed to quantify the percentage of flesh of each species used for can processing. The first one was based on absolute quantification using standard curves realized with these two markers; the second one was founded on relative quantification with the universal 12S rRNA gene as the endogenous gene. On the basis of our results, we conclude that our methodology could be applied to authenticate these two closely related tuna species when used in a binary mix in tuna cans.

  3. A comparative study of thermal calcination and an alkaline hydrolysis method in the isolation of hydroxyapatite from Thunnus obesus bone

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    Venkatesan, Jayachandran; Ryu, BoMi; Thomas, Noel Vinay; Kim, Se Kwon; Qian Zhongji

    2011-01-01

    In the present study, hydroxyapatite (HAp) was isolated from Thunnus obesus bone using alkaline hydrolysis and thermal calcination methods. The obtained ceramic has been characterized by thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), powder x-ray diffraction analysis (XRD), field-emission scanning electron microscopy, energy-dispersive x-ray analysis, transmission electron microscopy (TEM), selected area diffraction analysis, cytotoxic analysis and cell proliferation analysis. The results indicate that there are significant differences between the ceramics and T. obesus bone. FT-IR and TGA results affirmed that the collagen and organic moieties have been eliminated by both the proposed methods. XRD results were in agreement with JCPDS data. TEM and selective area diffraction images have signified that the thermal calcination method produces good crystallinity with dimensions 0.3-1.0 μm, whereas the alkaline hydrolysis method produces nanostructured HAp crystals with 17-71 nm length and 5-10 nm width. Biocompatibility of HAp crystals was evaluated by cytotoxicity and cell proliferation with human osteoblast-like cell MG-63.

  4. A comparative study of thermal calcination and an alkaline hydrolysis method in the isolation of hydroxyapatite from Thunnus obesus bone

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    Venkatesan, Jayachandran; Ryu, BoMi; Thomas, Noel Vinay; Kim, Se Kwon [Department of Chemistry, Pukyong National University, Busan 608-737 (Korea, Republic of); Qian Zhongji, E-mail: sknkim@pknu.ac.kr [Marine Bioprocess Research Center, Pukyong National University, Busan 608-737 (Korea, Republic of)

    2011-06-15

    In the present study, hydroxyapatite (HAp) was isolated from Thunnus obesus bone using alkaline hydrolysis and thermal calcination methods. The obtained ceramic has been characterized by thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), powder x-ray diffraction analysis (XRD), field-emission scanning electron microscopy, energy-dispersive x-ray analysis, transmission electron microscopy (TEM), selected area diffraction analysis, cytotoxic analysis and cell proliferation analysis. The results indicate that there are significant differences between the ceramics and T. obesus bone. FT-IR and TGA results affirmed that the collagen and organic moieties have been eliminated by both the proposed methods. XRD results were in agreement with JCPDS data. TEM and selective area diffraction images have signified that the thermal calcination method produces good crystallinity with dimensions 0.3-1.0 {mu}m, whereas the alkaline hydrolysis method produces nanostructured HAp crystals with 17-71 nm length and 5-10 nm width. Biocompatibility of HAp crystals was evaluated by cytotoxicity and cell proliferation with human osteoblast-like cell MG-63.

  5. Evaluating alternative management strategies for bigeye tuna, Thunnus obesus, in the Indian Ocean

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    Yuhe Tong

    2013-09-01

    Full Text Available Bigeye tuna (Thunnus obesus support a large commercial fishery in the Indian Ocean. However, explicit management strategies and harvest control rules are yet to be developed for the management of this fishery. We used a stochastic age-structured production model as an operating model to evaluate several potential management strategies under different assumptions of stock productivity. Five management strategies—constant fishing mortality, constant catch, quasi-constant catch, constant escapement, and status-dependent strategies—were evaluated and compared using the performance indicators including average catch, average spawning stock biomass, variation in catch, average fishing mortality and lowest biomass during the time period considered in the simulation. This study shows that (1 for the constant catch strategy, an annual catch of 90000 t would result in a low risk of stock being overfished while obtaining a stable catch; (2 for the constant fishing mortality strategy fishing mortality of 0.3 per year could yield a higher catch, but might have a high probability (64% of stock dropping below the spawning stock biomass (SSB that could achieve maximum sustainable yield (SSBmsy; and (3 for the quasi-constant catch strategy an annual catch of 110000 t was sustainable if the current SSB was higher than SSBmsy. Constant escapement and status-dependent strategies were robust with respect to different levels of virgin recruitment and steepness. This study suggests that it is important to incorporate uncertainties associated with key life history, fisheries and management processes in evaluating management strategies.

  6. DISTRIBUSI SPASIAL DAN TEMPORAL IKAN TUNA MATA BESAR (Thunnus obesus DI SAMUDERA HINDIA BAGIAN TIMUR

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    Irwan Jatmiko

    2016-03-01

    Full Text Available Ikan tuna mata besar (Thunnus obesus merupakan salah satu hasil tangkapan yang penting bagi industri perikanan di Indonesia. Penelitian ini bertujuan untuk mengetahui distribusi spasial dan temporal ikan tuna mata besar di Samudera Hindia Bagian Timur. Pengumpulan data dilakukan oleh pemantau ilmiah (scientific observers pada kapal rawai tuna yang berbasis di Pelabuhan Benoa Bali, mulai Agustus 2005 hingga November 2013. Ikan tuna mata besar yang tertangkap sebanyak 5.340 ekor dan dari jumlah tersebut sebanyak 5.253 ekor diukur panjangnya. Distribusi spasial ikan tuna mata besar yang tertangkap rawai tuna Indonesia membentang dari 0°-33° LS dan 76°-128° BT. Persentase tertinggi ikan tuna mata besar dengan panjang >110 cm (Lm terdapat di sebelah barat Sumatera Barat dan di sebelah selatan Jawa Timur. Laju pancing menurut bulan penagkapan menunjukkan perbedaan yang nyata dengan laju pancing tertinggi terjadi pada Agustus sebesar 0,54 ekor/100 mata pancing. Nelayan direkomendasikan untuk melakukan operasi penangkapan di daerah dengan persentase ukuran panjang ikan tuna mata besar >110 cm (Lm tertinggi, sehingga species tersebut mempunyai kesempatan untuk melakukan pemijahan minimal sekali sepanjang hidupnya. Hal ini dimaksudkan untuk menjaga kelestarian sumberdaya ikan tuna mata besar di Samudera Hindia. Big eye tuna (Thunnus obesus is one of the important catch of the fishing industry in Indonesia. The study is aimed to investigate the spatial and temporal distribution of big eye tuna in the Eastern Indian Ocean. Data were collected by scientific observers on tuna long line vessels which were mainly based in Port of Benoa Bali from August 2005 to November 2013. Total number of big eye tuna caught were 5,340 individuals and as many as 5,253 of them were measured in length. The spatial distribution of  big eye tuna caught by Indonesia tuna long line are in the area between 0°-33° S and 76°-128° E. The highest percentage of big eye tuna with

  7. Transectional heat transfer in thermoregulating bigeye tuna (Thunnus obesus) - a 2D heat flux model.

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    Boye, Jess; Musyl, Michael; Brill, Richard; Malte, Hans

    2009-11-01

    We developed a 2D heat flux model to elucidate routes and rates of heat transfer within bigeye tuna Thunnus obesus Lowe 1839 in both steady-state and time-dependent settings. In modeling the former situation, we adjusted the efficiencies of heat conservation in the red and the white muscle so as to make the output of the model agree as closely as possible with observed cross-sectional isotherms. In modeling the latter situation, we applied the heat exchanger efficiencies from the steady-state model to predict the distribution of temperature and heat fluxes in bigeye tuna during their extensive daily vertical excursions. The simulations yielded a close match to the data recorded in free-swimming fish and strongly point to the importance of the heat-producing and heat-conserving properties of the white muscle. The best correspondence between model output and observed data was obtained when the countercurrent heat exchangers in the blood flow pathways to the red and white muscle retained 99% and 96% (respectively) of the heat produced in these tissues. Our model confirms that the ability of bigeye tuna to maintain elevated muscle temperatures during their extensive daily vertical movements depends on their ability to rapidly modulate heating and cooling rates. This study shows that the differential cooling and heating rates could be fully accounted for by a mechanism where blood flow to the swimming muscles is either exclusively through the heat exchangers or completely shunted around them, depending on the ambient temperature relative to the body temperature. Our results therefore strongly suggest that such a mechanism is involved in the extensive physiological thermoregulatory abilities of endothermic bigeye tuna.

  8. Evaluation of three harvest control rules for Bigeye Tuna ( Thunnus obesus) fisheries in the Indian Ocean

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    Tong, Yuhe; Chen, Xinjun; Kolody, Dale

    2014-10-01

    The stock of Bigeye tuna ( Thunnus obesus) in the Indian Ocean supports an important international fishery and is considered to be fully exploited. The responsible management agency, the Indian Ocean Tuna Commission (IOTC), does not have an explicit management decision-making framework in place to prevent over-fishing. In this study, we evaluated three harvest control rules, i) constant fishing mortality (CF), from 0.2 to 0.6, ii) constant catch (CC), from 60000 to 140000 t, and iii) constant escapement (CE), from 0.3 to 0.7. The population dynamics simulated by the operating model was based on the most recent stock assessment using Stock Synthesis version III (SS3). Three simulation scenarios (low, medium and high productivity) were designed to cover possible uncertainty in the stock assessment and biological parameters. Performances of three harvest control rules were compared on the basis of three management objectives (over 3, 10 and 25 years): i) the probability of maintaining spawning stock biomass above a level that can sustain maximum sustainable yield (MSY) on average, ii) the probability of achieving average catches between 0.8 MSY and 1.0 MSY, and iii) inter-annual variability in catches. The constant escapement strategy ( CE=0.5), constant fishing mortality strategy ( F=0.4) and constant catch ( CC=80000) were the most rational among the respective management scenarios. It is concluded that the short-term annual catch is suggested at 80000 t, and the potential total allowable catch for a stable yield could be set at 120000 t once the stock had recovered successfully. All the strategies considered in this study to achieve a `tolerable' balance between resource conservation and utilization have been based around the management objectives of the IOTC.

  9. MASS SPECTROMETRIC ANALYSIS FOR THE IDENTIFICATION OF THUNNUS GENUS FOUR SPECIES

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    T. Pepe

    2011-01-01

    Full Text Available An accurate identification of similar fish species is necessary to prevent illegal substitution and is imposed by labeling regulations in UE countries (1. The genus Thunnus comprises many species of different quality and commercial value. The increasing trade of fish preparations of the species included in this genus and the consequent loss of the external anatomical and morphological features enables fraudulent substitutions. This study reports data relating to the proteomic analysis of four tuna species (T. thynnus, T. alalunga, T. albacares, T. obesus. Sarcoplasmic proteins were studied by mono and two dimensional electrophoresis. The most significant proteins for the characterization of the species were analyzed by mass spectrometric techniques. As reported in a previous study (2, an accurate identification of the species seems possible, owing to the polymorphism displayed by the species of the Thunnus genus.

  10. Notes on helminth parasites of tuna fishes (Scombridae in Brazil Notas sobre los helmintos parásitos del atún (Scombridae en Brasil

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    Márcia Cristina Nascimento-Justo

    2012-03-01

    Full Text Available Four species of Scombridae from the coast of Rio de Janeiro, southwest Atlantic Ocean were found to be parasitized with species of Didymozoidae (Digenea: Thunnus atlanticus (Lesson a new host record for Nephrodidymotrema ahi Yamaguti, 1970, Didymocystis neothunni (Yamaguti, 1970, and Didymozoon longicolle (Yamaguti, 1970; Thunnus obesus (Lowe parasitized by Didymozoon longicolle and reported as a new host for Nephrodidymotrema ahi; Thunnus albacares (Bonaterre parasitized by Nephrodidymotrema ahi, and Katsuwonus pelamis (Linnaeus by Didymozoon longicolle. Measurements, figures, and parameters of infection are presented.Cuatro especies de Scombridae de la costa de Río de Janeiro, suroeste del océano Atlántico, se reportan parasitados con diferentes especies de Didymozoidae (Digenea: Thunnus atlanticus (Lesson un registro de nuevo huésped para Nephrodidymotrema ahi Yamaguti, 1970, Didymocystis neothunni (Yamaguti, 1970 y para Didymozoon longicolle (Yamaguti, 1970; Thunnus obesus (Lowe parasitado por Didymozoon longicolle, se indica como nuevo huésped para Nephrodidymotrema ahi; Thunnus albacares (Bonaterre parasitados por Nephrodidymotrema ahi y Katsuwonus pelamis (Linnaeus por Didymozoon longicolle. Se presentan las mediciones, las figuras y los parámetros de la infección.

  11. Form and function of the bulbus arteriosus in yellowfin tuna (Thunnus albacares), bigeye tuna (Thunnus obesus) and blue marlin (Makaira nigricans): static properties.

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    Braun, Marvin H; Brill, Richard W; Gosline, John M; Jones, David R

    2003-10-01

    The juxtaposition of heart and gills in teleost fish means that the Windkessel function characteristic of the whole mammalian arterial tree has to be subserved by the extremely short ventral aorta and bulbus arteriosus. Over the functional pressure range, arteries from blue marlin (Makaira nigricans) and yellowfin tuna (Thunnus albacares) have J-shaped pressure-volume (P-V) loops, while bulbi from the same species have r-shaped P-V loops, with a steep initial rise followed by a compliant plateau phase. The steep initial rise in pressure is due to the geometry of the lumen. The interactions between radius, pressure and tension require a large initial pressure to open the bulbar lumen for flow. The plateau is due to the unique organization of the bulbar wall. The large elastin:collagen ratio, limited amount of collagen arranged circumferentially, lack of elastin lamellae and low hydrophobicity of the elastin itself all combine to lower stiffness, increase extensibility and allow efficient recoil. Even though the modulus of bulbus material is much lower than that of an artery, at large volumes the overall stiffness of the bulbus increases rapidly. The morphological features that give rise to the special inflation characteristics of the bulbus help to extend flow and maintain pressure during diastole.

  12. Revisiting the vulnerability of juvenile bigeye (Thunnus obesus) and yellowfin (T. albacares) tuna caught by purse-seine fisheries while associating with surface waters and floating objects.

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    Scutt Phillips, Joe; Pilling, Graham M; Leroy, Bruno; Evans, Karen; Usu, Thomas; Lam, Chi Hin; Schaefer, Kurt M; Nicol, Simon

    2017-01-01

    Tuna fisheries catch over three million tonnes of skipjack tuna (Katsuwonus pelamis) each year, the majority of which come from purse-seine vessels targeting fish associated with man-made fish aggregating devices (FADs). A significant challenge for fisheries management is to maximize the efficiency of skipjack tuna catches whilst minimizing the bycatch of small and immature bigeye (Thunnus obesus) and yellowfin (T. albacares) tuna, for which long-term sustainability is uncertain in 75% of the world's stocks. To better manage the issues common with this fishing method, an improved understanding of tuna behaviour around FADs is necessary. We probabilistically classified the vertical behavioural patterns of 50 bigeye and 35 yellowfin tuna (mean fork length 72cm and 70cm, respectively) electronically tagged throughout the western and central Pacific Ocean into shallow and deep states, using a state-space modelling approach. The occurrence of surface-association behaviours, defined as an individual remaining in a shallow state for 24-hours, was examined in relation to known capture events and FAD density. In general, surface-association events for both species were short and lasted on average less than three days, although events as long as 28 days were observed, and were more common in yellowfin when in archipelagic waters. Events were longest immediately following tagging in 62% and 17% of bigeye and yellowfin, respectively. Surface-association behaviour was not generally estimated just prior to recapture, being either non-existent or shorter than two days for 85% of bigeye and 74% of yellowfin. Current management measures in purse-seine tuna fisheries involve periodic or spatial closures for FAD use. If the chief benefit to purse-seine fishers of surface-association around floating objects is in locating schools in horizontal space at short-term time-scales, rather than holding fish near the surface for extended periods, controlling the number of sets made on FADs

  13. Revisiting the vulnerability of juvenile bigeye (Thunnus obesus and yellowfin (T. albacares tuna caught by purse-seine fisheries while associating with surface waters and floating objects.

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    Joe Scutt Phillips

    Full Text Available Tuna fisheries catch over three million tonnes of skipjack tuna (Katsuwonus pelamis each year, the majority of which come from purse-seine vessels targeting fish associated with man-made fish aggregating devices (FADs. A significant challenge for fisheries management is to maximize the efficiency of skipjack tuna catches whilst minimizing the bycatch of small and immature bigeye (Thunnus obesus and yellowfin (T. albacares tuna, for which long-term sustainability is uncertain in 75% of the world's stocks. To better manage the issues common with this fishing method, an improved understanding of tuna behaviour around FADs is necessary. We probabilistically classified the vertical behavioural patterns of 50 bigeye and 35 yellowfin tuna (mean fork length 72cm and 70cm, respectively electronically tagged throughout the western and central Pacific Ocean into shallow and deep states, using a state-space modelling approach. The occurrence of surface-association behaviours, defined as an individual remaining in a shallow state for 24-hours, was examined in relation to known capture events and FAD density. In general, surface-association events for both species were short and lasted on average less than three days, although events as long as 28 days were observed, and were more common in yellowfin when in archipelagic waters. Events were longest immediately following tagging in 62% and 17% of bigeye and yellowfin, respectively. Surface-association behaviour was not generally estimated just prior to recapture, being either non-existent or shorter than two days for 85% of bigeye and 74% of yellowfin. Current management measures in purse-seine tuna fisheries involve periodic or spatial closures for FAD use. If the chief benefit to purse-seine fishers of surface-association around floating objects is in locating schools in horizontal space at short-term time-scales, rather than holding fish near the surface for extended periods, controlling the number of sets

  14. Rapid development of non-alcoholic steatohepatitis in Psammomys obesus (Israeli sand rat.

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    Briana Spolding

    Full Text Available BACKGROUND AND AIMS: A major impediment to establishing new treatments for non-alcoholic steatohepatitis is the lack of suitable animal models that accurately mimic the biochemical and metabolic characteristics of the disease. The aim of this study was to explore a unique polygenic animal model of metabolic disease as a model of non-alcoholic steatohepatitis by determining the effects of 2% dietary cholesterol supplementation on metabolic and liver endpoints in Psammomys obesus (Israeli sand rat. METHODS: P. obesus were provided ad libitum access to either a standard rodent diet (20% kcal/fat or a standard rodent diet supplemented with 2% cholesterol (w/w for 4 weeks. Histological sections of liver from animals on both diets were examined for key features of non-alcoholic steatohepatitis. The expression levels of key genes involved in hepatic lipid metabolism were measured by real-time PCR. RESULTS: P. obesus fed a cholesterol-supplemented diet exhibited profound hepatomegaly and steatosis, and higher plasma transaminase levels. Histological analysis identified extensive steatosis, inflammation, hepatocyte injury and fibrosis. Hepatic gene expression profiling revealed decreased expression of genes involved in delivery and uptake of lipids, and fatty acid and triglyceride synthesis, and increased expression of genes involved in very low density lipoprotein cholesterol synthesis, triglyceride and cholesterol export. CONCLUSIONS: P. obesus rapidly develop non-alcoholic steatohepatitis when fed a cholesterol-supplemented diet that appears to be histologically and mechanistically similar to patients.

  15. Psammomys obesus Cretzschmar, 1828 and zoonotic cutaneous leishmaniasis in Sinai Peninsula, Egypt.

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    Morsy, T A; Sabry, A H; Rifaat, M M; Wahba, M M

    1996-08-01

    In the Middle East, the fat sand rat Psammomys obesus is the most important reservoir host of zoonotic cutaneous leishmamiasis (ZCL). It is the most incriminated host in outbreaks. Two P. obesus caught in Wadi El Gedeiret (Al Arish, North Sinai) were found naturally infected with Leishmania major as indicated by enzyme electrophoresis. In Egypt, the already known reservoir hosts are Gerbillus pyramidum I. Geoffroy St. Hilaire, 1825; Meriones crassus Sundevall, 1984 and Meriones sacramenti Thomas, 1922. The hostal role of P. obesus was discussed.

  16. Genetic structuring and migration patterns of Atlantic bigeye tuna, Thunnus obesus (Lowe, 1839

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    Beerli Peter

    2008-09-01

    Full Text Available Abstract Background Large pelagic fishes are generally thought to have little population genetic structuring based on their cosmopolitan distribution, large population sizes and high dispersal capacities. However, gene flow can be influenced by ecological (e.g. homing behaviour and physical (e.g. present-day ocean currents, past changes in sea temperature and levels factors. In this regard, Atlantic bigeye tuna shows an interesting genetic structuring pattern with two highly divergent mitochondrial clades (Clades I and II, which are assumed to have been originated during the last Pleistocene glacial maxima. We assess genetic structure patterns of Atlantic bigeye tuna at the nuclear level, and compare them with mitochondrial evidence. Results We examined allele size variation of nine microsatellite loci in 380 individuals from the Gulf of Guinea, Canary, Azores, Canada, Indian Ocean, and Pacific Ocean. To investigate temporal stability of genetic structure, three Atlantic Ocean sites were re-sampled a second year. Hierarchical AMOVA tests, RST pairwise comparisons, isolation by distance (Mantel tests, Bayesian clustering analyses, and coalescence-based migration rate inferences supported unrestricted gene flow within the Atlantic Ocean at the nuclear level, and therefore interbreeding between individuals belonging to both mitochondrial clades. Moreover, departures from HWE in several loci were inferred for the samples of Guinea, and attributed to a Wahlund effect supporting the role of this region as a spawning and nursery area. Our microsatellite data supported a single worldwide panmictic unit for bigeye tunas. Despite the strong Agulhas Current, immigration rates seem to be higher from the Atlantic Ocean into the Indo-Pacific Ocean, but the actual number of individuals moving per generation is relatively low compared to the large population sizes inhabiting each ocean basin. Conclusion Lack of congruence between mt and nuclear evidences, which

  17. Genetic structuring and migration patterns of Atlantic bigeye tuna, Thunnus obesus (Lowe, 1839).

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    Gonzalez, Elena G; Beerli, Peter; Zardoya, Rafael

    2008-09-17

    Large pelagic fishes are generally thought to have little population genetic structuring based on their cosmopolitan distribution, large population sizes and high dispersal capacities. However, gene flow can be influenced by ecological (e.g. homing behaviour) and physical (e.g. present-day ocean currents, past changes in sea temperature and levels) factors. In this regard, Atlantic bigeye tuna shows an interesting genetic structuring pattern with two highly divergent mitochondrial clades (Clades I and II), which are assumed to have been originated during the last Pleistocene glacial maxima. We assess genetic structure patterns of Atlantic bigeye tuna at the nuclear level, and compare them with mitochondrial evidence. We examined allele size variation of nine microsatellite loci in 380 individuals from the Gulf of Guinea, Canary, Azores, Canada, Indian Ocean, and Pacific Ocean. To investigate temporal stability of genetic structure, three Atlantic Ocean sites were re-sampled a second year. Hierarchical AMOVA tests, RST pairwise comparisons, isolation by distance (Mantel) tests, Bayesian clustering analyses, and coalescence-based migration rate inferences supported unrestricted gene flow within the Atlantic Ocean at the nuclear level, and therefore interbreeding between individuals belonging to both mitochondrial clades. Moreover, departures from HWE in several loci were inferred for the samples of Guinea, and attributed to a Wahlund effect supporting the role of this region as a spawning and nursery area. Our microsatellite data supported a single worldwide panmictic unit for bigeye tunas. Despite the strong Agulhas Current, immigration rates seem to be higher from the Atlantic Ocean into the Indo-Pacific Ocean, but the actual number of individuals moving per generation is relatively low compared to the large population sizes inhabiting each ocean basin. Lack of congruence between mt and nuclear evidences, which is also found in other species, most likely reflects

  18. Developmental biology of the Psammomys obesus pancreas

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    Vedtofte, Louise; Bödvarsdóttir, Thóra B; Karlsen, Allan E

    2007-01-01

    The desert gerbil Psammomys obesus, an established model of type 2 diabetes (T2D), has previously been shown to lack pancreatic and duodenal homeobox gene 1 (Pdx-1) expression. Pdx-1 deficiency leads to pancreas agenesis in both mice and humans. We have therefore further examined the pancreas of ...

  19. Upregulation of alpha cell glucagon-like peptide 1 (GLP-1) in Psammomys obesus--an adaptive response to hyperglycaemia?

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    Hansen, A M K; Bödvarsdottir, T B; Nordestgaard, D N E

    2011-01-01

    of the study was to evaluate if, during the development of diabetes, alpha cells produce GLP-1 that, in turn, might trigger beta cell growth. Methods Beta cell mass, GLP-1 and insulin levels were measured in the gerbil Psammomys obesus (P. obesus), a rodent model of nutritionally induced diabetes. Furthermore...... from alpha cells is upregulated in P. obesus during the development of diabetes. A similar response is seen in islets exposed to high glucose, which supports the hypothesis that GLP-1 released from alpha cells promotes an increase in beta cell mass and function during metabolic challenge...

  20. Influence of salinity on prevalence of the parasite Loxothylacus panopaei in the xanthid Panopeus obesus in SW Florida.

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    Tolley, S Gregory; Winstead, James T; Haynes, Lesli; Volety, Aswani K

    2006-06-23

    This study was conducted to examine the potential influence of salinity, a proxy for freshwater inflow, on the prevalence of the castrator parasite Loxothylacus panopaei on saltmarsh mud crabs Panopeus obesus on SW Florida oyster reefs. Spatial and seasonal patterns of the presence of potential host crabs and the prevalence of the parasite were assessed in the Caloosahatchee, Estero, and Faka Union estuaries. Lift nets (1 m2) containing 5 1 of oyster clusters were deployed on intertidal reefs at 3 sites along the salinity gradient of each estuary. Nets were deployed during 3 seasonally dry and 3 seasonally wet months for a period of 30 d. P. obesus densities tended to increase downstream in higher salinity waters, with crabs being absent from the upper station in the Caloosahatchee during both seasons and absent from the upper station of the Faka Union during wet months. Parasite prevalence was reduced upstream in each estuary during wet months compared to dry months, and for those estuaries that experienced higher relative levels of freshwater inflow. Furthermore, parasite prevalence was positively correlated with the mean salinity of capture of host crabs. Based on the distribution of P. obesus and the above patterns related to salinity, it appears that freshwater inflow and seasonal rains might regulate the prevalence of this parasite in SW Florida by creating spatiotemporal, low salinity refuges for its host.

  1. Liraglutide, but not vildagliptin, restores normoglycaemia and insulin content in the animal model of type 2 diabetes, Psammomys obesus

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    Vedtofte, Louise; Bodvarsdottir, Thóra B; Gotfredsen, Carsten F

    2010-01-01

    In order to investigate the effect and mechanism of liraglutide and vildagliptin in diabetic Psammomys obesus, we examined proliferation and apoptosis of beta-cells, beta-cell mass (BCM), and pancreatic insulin content after zero, six and fourteen days of treatment compared to control groups. One......, compared to the vehicle-treated animals pancreatic insulin content was normalized in animals treated for six and fourteen days with liraglutide. In contrast, vildagliptin, in doses causing full inhibition of plasma DPP-IV activity, neither reduced blood glucose nor altered HED-induced increases in BCM...... or pancreatic insulin content. These results suggest that liraglutide restores normoglycaemia and improves glycaemic control in P. obesus by increasing their insulin content and improving the function of the beta-cells. In contrast, vildagliptin does not improve glycaemic control in P. obesus nor affect beta...

  2. Effects of the North Atlantic Oscillation on Spanish catches of albacore, Thunnus alalunga, and yellowfin tuna, Thunnus albacares, in the North–east Atlantic Ocean

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    Rubio, C.J.; MacIas, D.; Camiñas, J.A.; Fernandez, I.L.; Baez, J.C.

    2016-07-01

    Tuna are highly migratory pelagic species (HMPS) with great importance in commercial fishing. Several authors have highlighted the effect of climatic oscillations such as the NAO (North Atlantic Oscillation) on HMPS. This paper analyzes the effects of the NAO on two HMPS: albacore, Thunnus alalunga, and yellowfin tuna, Thunnus albacares. Fishing data from the Spanish fleet operating in the North Atlantic area were obtained from the International Commission for the Conservation of Atlantic Tunas (ICCAT) database. The results show a positive correlation between the NAO index and the Catch per Unit Effort (CPUE) for both albacore and yellowfin tuna, depicting a potential effect on their capturability. (Author)

  3. Genetic structuring and migration patterns of Atlantic bigeye tuna, Thunnus obesus (Lowe, 1839)

    OpenAIRE

    Gonzalez, Elena G; Beerli, Peter; Zardoya, Rafael

    2008-01-01

    Abstract Background Large pelagic fishes are generally thought to have little population genetic structuring based on their cosmopolitan distribution, large population sizes and high dispersal capacities. However, gene flow can be influenced by ecological (e.g. homing behaviour) and physical (e.g. present-day ocean currents, past changes in sea temperature and levels) factors. In this regard, Atlantic bigeye tuna shows an interesting genetic structuring pattern with two highly divergent mitoc...

  4. [Association of the abundance and vertical distribution of tuna and beakfish in the southeast of the Caribbean sea].

    Science.gov (United States)

    Eslava, Nora; González, Leo W; Gaertner, Daniel

    2003-03-01

    The longline hooks suspension depth was estimated using the Mechanic Imitation of Flexible Systems method. The vertical distribution of tunas and billfish was determined by the relative abundance index, obtained from the catch by 11 to 25 m -long longline vessels, -based at Cumaná, Venezuela, South-eastern Caribbean Sea in depths of 65 to 142 m. The CPUE was evaluated per species, according to depth. High values were found for most of the captured species in the layer from 105 to 125 m. Yellowfin tuna (Thunnus albacares) showed the highest yield (3.37 fish/100 hooks) and blue marlin (Makaira nigricans) the lowest (0.04 fish/100 hooks). However, the statistical comparison did not allow to reject the hypothesis of lack of depth efect (Kruskal-Wallis p > .05), and demonstrated a homogeneous distribution of yellowfin tuna (Thunnus albacares), albacore (Thunnus alalunga), bigeye tuna (Thunnus obesus), sailfish (Istiophorus albicans), white marlin (Tetrapturus albidus) and blue marlin (Makaira nigricans) in the water column. The conclusion is that fish concentration in the Southern border of the Caribbean Sea is possibly due to several hydroclimatic factors--which affect tuna and billfish catching--such as water temperature and dissolved oxygen concentration which limit the distribution according to depth.

  5. Tuna Species Substitution in the Spanish Commercial Chain: A Knock-On Effect.

    Directory of Open Access Journals (Sweden)

    Ana Gordoa

    Full Text Available Intentional mislabelling of seafood is a widespread problem, particularly with high-value species like tuna. In this study we examine tuna mislabelling, deliberate species substitution, types of substitution and its impact on prices. The survey covered the commercial chain, from Merca-Barna to fishmongers and restaurants in the Spanish Autonomous Community of Catalonia. To understand the geographic extent of the problem we also sampled Merca-Madrid, Europe's biggest fish market, and Merca-Málaga for its proximity to the bluefin tuna migratory route and trap fishery. Monthly surveys were carried out over one year. The results showed a high deficiency in labelling: 75% of points of sale and 83% of restaurants did not specify the species, and in those cases the name of the species had to be asked. A total of 375 samples were analysed genetically, the largest dataset gathered in Europe so far. The identified species were Thunnus albacares, Thunnus thynnus and Thunnus obesus. Species substitution began at suppliers, with 40% of observed cases, increasing to 58% at fishmongers and 62% at restaurants. The substitution was mainly on bluefin tuna (T. thynnus, 73% of cases. At restaurants, only during the bluefin fishing season, we observed a decrease of Bluefin tuna substitution and an increase of reverse substitution revealing some illegal fishing. The effect of species substitution on species prices was relevant: T. obesus increased its price by around €12 kg-1 when it was sold as bluefin. In view of the deficiency of labelling, the abuse of generic names and the lack of the bluefin catch document, we conclude that the Spanish regulations are ineffective, highlighting the need for policy execution, and the urgent need for information campaigns to Spanish consumers.

  6. Asociación de la abundancia y la distribución vertical de atunes y peces de pico en el sureste del Mar Caribe

    Directory of Open Access Journals (Sweden)

    Nora Eslava

    2003-03-01

    Full Text Available Se estimó la profundidad de suspensión de los anzuelos del palangre usando el método de Imitación Mecánica de los Sistemas Flexibles, mientras que la distribución vertical de atunes y peces de pico se determinó mediante el índice de abundancia relativa obtenido de capturas de barcos palangreros (11 a 25 m de eslora del puerto de Cumaná, Venezuela y que operan en el Mar Caribe a una profundidad de 65 a 142 m. Se evaluó la CPUE por especie de acuerdo a la profundidad, encontrándose valores altos en la mayoría de los individuos de las especies capturadas en el estrato de 105 a 125 m. El atún aleta amarilla (Thunnus albacares fue el que presentó los más altos rendimientos (3.37 peces/100 anzuelos, mientras que la aguja azul (Makaira nigricans los más bajos (0.04 peces/100 anzuelos. La comparación estadística no permitió rechazar la hipótesis de ausencia del efecto de profundidad (Kruskal-Wallis p > .05, y se puso en evidencia una distribución homogénea, en la columna de agua, del atún aleta amarilla (Thunnus albacares, albacora (Thunnus alalung a, ojo gordo (Thunnus obesus, pez vela (Istiophorus albican s, aguja blanca (Tetrapturus albidus y aguja azul (Makaira nigrican s. Se concluye que la concentración de la pesca en el margen sur del Mar Caribe, posiblemente, es debido a varios factores hidroclimáticos tales como la temperatura del agua y la concentración de oxígeno disuelto que influyen sobre la captura de los atunes y peces de pico delimitando su distribución con res-pecto a la profundidad.The longline hooks suspension depth was estimated using the Mechanic Imitation of Flexible Systems method. The vertical distribution of tunas and billfish was determined by the relative abundance index, obtained from the catch by 11 to 25 m -long longline vessels, -based at Cumaná, Venezuela, South-eastern Caribbean Sea in depths of 65 to 142 m. The CPUE was evaluated per species, according to depth. High values were found for

  7. Oro-gustatory perception of dietary lipids and calcium signaling in taste bud cells are altered in nutritionally obesity-prone Psammomys obesus.

    Science.gov (United States)

    Abdoul-Azize, Souleymane; Atek-Mebarki, Feriel; Bitam, Arezki; Sadou, Hassimi; Koceïr, Elhadj Ahmed; Khan, Naim Akhtar

    2013-01-01

    Since the increasing prevalence of obesity is one of the major health problems of the modern era, understanding the mechanisms of oro-gustatory detection of dietary fat is critical for the prevention and treatment of obesity. We have conducted the present study on Psammomys obesus, the rodent desert gerbil which is a unique polygenic natural animal model of obesity. Our results show that obese animals exhibit a strong preference for lipid solutions in a two-bottle test. Interestingly, the expression of CD36, a lipido-receptor, in taste buds cells (TBC), isolated from circumvallate papillae, was decreased at mRNA level, but remained unaltered at protein level, in obese animals. We further studied the effects of linoleic acid (LA), a long-chain fatty acid, on the increases in free intracellular calcium (Ca(2+)) concentrations, [Ca(2+)]i, in the TBC of P. obesus. LA induced increases in [Ca(2+)]i, largely via CD36, from intracellular pool, followed by the opening of store-operated Ca(2+) (SOC) channels in the TBC of these animals. The action of this fatty acid on the increases in [Ca(2+)]i was higher in obese animals than that in controls. However, the release of Ca(2+) from intracellular stores, studied also by employing thapsigargin, was lower in TBC of obese animals than control rodents. In this study, we show, for the first time, that increased lipid intake and altered Ca(2+) signaling in TBC are associated with obesity in Psammomys obesus.

  8. Muscular system in the pacific bluefin tuna Thunnus orientalis (Teleostei: Scombridae).

    Science.gov (United States)

    Nakae, Masanori; Sasaki, Kunio; Shinohara, Gento; Okada, Tokihiko; Matsuura, Keiichi

    2014-02-01

    The muscular system in the Pacific bluefin tuna Thunnus orientalis is studied in detail. For the first time, a complete description of the muscular anatomy of a thunnid is provided here. Eighty-two elements including subdivisions of components of the muscular system are identified. This is less than found in a basal perciform and two other investigated scombrid species, owing mainly to the absence or fusion of pectoral, pelvic and caudal fin muscles. The absence of elements of the basal perciform pattern was most prominent in the caudal fin, which includes only the flexor dorsalis, flexor ventralis, hypochordal longitudinalis, and interradialis. In the caudal fin, the medial fan-shaped ray was identified as the first dorsal ray, judging from myological and neuroanatomical characters. The highly developed gill filament muscles in Thunnus orientalis and sheet-like rectus communis control gill ventilation. Long body muscle tendons reduce the metabolic energy needed during rapid and continuous swimming. These characters are interpreted as adaptations in the context of the oceanic life style of the species. Copyright © 2013 Wiley Periodicals, Inc.

  9. Atherosclerosis and atherosensitivity in two southwest Algerian desert rodents, Psammomys obesus and Gerbillus gerbillus, and in Rattus norvegicus

    Directory of Open Access Journals (Sweden)

    El-Aoufi S

    2012-09-01

    Full Text Available Salima El-Aoufi,1 Mohamed-Amine Lazourgui,1 Lakhdar Griene,2 Boubekeur Maouche31Laboratoire de Biologie et de Physiologie des Organismes/MMDED, Faculté des Sciences Biologiques, USTHB, El-Alia, Dar El Beida, Algeria; 2Laboratoire d'Hormonologie, Centre Pierre et Marie Curie, C.H.U Mustapha, Algeria; 3Laboratoire de Physicochimie Théorique et Chimie Informatique, Faculté de Chimie, USTHB, El-Alia, Dar El Beida, AlgeriaAbstract: Cardiovascular disease, including atherosclerosis, is the leading cause of death in patients with diabetes worldwide; thus, it is a major medical concern. The endothelium contributes to the control of many vascular functions, and clinical observations show that it is a primary target for diabetic syndrome. To get better insight into the mechanisms underlying atherosclerosis, we studied the interspecific differences in the arterial metabolisms of two, Psammomys obesus and Gerbillus gerbillus, as well as Rattus norvegicus (Wistar rat, well known for its atheroresistance. Twenty-two enzymatic activities and six macromolecular substances were histochemically compared in the two desert species and in Wistar aortas (abdominal and thoracic and arteries (femoral and caudal embedded in a common block. In the healthy adult rodents, enzyme activities were very intense. They demonstrated that aortic myocytes are capable of various synthesis and catabolism processes. However, considering the frequency of atherosclerosis and its phenotypes, significant differences appeared between the species studied. Our comparative study shows that aortic atherosensitive animals have several common metabolic characteristics, which are found in Psammomys rich in metachromatic glycosaminoglycans (involved in the inhibition of lipolysis and in calcification of the organic matrix, reduced activity in enzymes related to the Krebs cycle (weakening energetic power, and low lipolytic enzyme, adenosine triphosphatase, and adenosine diphosphatase activities

  10. Oro-gustatory perception of dietary lipids and calcium signaling in taste bud cells are altered in nutritionally obesity-prone Psammomys obesus.

    Directory of Open Access Journals (Sweden)

    Souleymane Abdoul-Azize

    Full Text Available Since the increasing prevalence of obesity is one of the major health problems of the modern era, understanding the mechanisms of oro-gustatory detection of dietary fat is critical for the prevention and treatment of obesity. We have conducted the present study on Psammomys obesus, the rodent desert gerbil which is a unique polygenic natural animal model of obesity. Our results show that obese animals exhibit a strong preference for lipid solutions in a two-bottle test. Interestingly, the expression of CD36, a lipido-receptor, in taste buds cells (TBC, isolated from circumvallate papillae, was decreased at mRNA level, but remained unaltered at protein level, in obese animals. We further studied the effects of linoleic acid (LA, a long-chain fatty acid, on the increases in free intracellular calcium (Ca(2+ concentrations, [Ca(2+]i, in the TBC of P. obesus. LA induced increases in [Ca(2+]i, largely via CD36, from intracellular pool, followed by the opening of store-operated Ca(2+ (SOC channels in the TBC of these animals. The action of this fatty acid on the increases in [Ca(2+]i was higher in obese animals than that in controls. However, the release of Ca(2+ from intracellular stores, studied also by employing thapsigargin, was lower in TBC of obese animals than control rodents. In this study, we show, for the first time, that increased lipid intake and altered Ca(2+ signaling in TBC are associated with obesity in Psammomys obesus.

  11. [Performance evaluation of a fluorescamine-HPLC method for determination of histamine in fish and fish products].

    Science.gov (United States)

    Kikuchi, Hiroyuki; Tsutsumi, Tomoaki; Matsuda, Rieko

    2012-01-01

    A method for the quantification of histamine in fish and fish products using tandem solid-phase extraction and fluorescence derivatization with fluorescamine was previously developed. In this study, we improved this analytical method to develop an official test method for quantification of histamine in fish and fish products, and performed a single laboratory study to validate it. Recovery tests of histamine from fillet (Thunnus obesus), and two fish products (fish sauce and salted and dried whole big-eye sardine) that were spiked at the level of 25 and 50 µg/g for T. obesus, and 50 and 100 µg/g for the two fish products, were carried out. The recoveries of histamine from the three samples tested were 88.8-99.6% with good repeatability (1.3-2.1%) and reproducibility (2.1-4.7%). Therefore, this method is acceptable for the quantification of histamine in fish and fish products. Moreover, surveillance of histamine content in food on the market was conducted using this method, and high levels of histamine were detected in some fish products.

  12. The small leucine-rich proteoglycan, biglycan, is highly expressed in adipose tissue of Psammomys obesus and is associated with obesity and type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Bolton K

    2012-04-01

    Full Text Available Kristy Bolton1, David Segal1, Ken Walder1,21Metabolic Research Unit, School of Medicine, 2Institute for Technology, Research and Innovation, Deakin University, Waurn Ponds, Victoria, AustraliaAbstract: We have previously demonstrated that the small leucine-rich proteoglycan decorin may play a role in adipose tissue homeostasis and the pathophysiology of obesity. Biglycan is highly similar in structure to decorin, therefore we hypothesized it would have a similar expression profile and role to decorin in adipose tissue. Real time polymerase chain reaction was used to measure biglycan mRNA levels in adipose tissue from normal glucose tolerant and impaired glucose tolerant and type 2 diabetic (T2D Psammomys obesus. Biglycan mRNA was found to be highly expressed in adipose tissue, and gene expression was significantly higher in visceral compared to subcutaneous adipose tissue, with elevated levels in obese, T2D compared to lean normal glucose tolerant P. obesus (P < 0.04. Biglycan mRNA was predominantly expressed by stromal/vascular cells of fractionated adipose tissue (P = 0.023. Biglycan expression in adipose tissue, particularly in the obese state, was markedly upregulated. Collectively, our data suggest that the small leucine-rich proteoglycan family proteins biglycan and decorin may play a role in the development of obesity and T2D, possibly by facilitating expansion of adipose tissue mass.Keywords: biglycan, small leucine-rich proteoglycan, Psammomys obesus, adipose tissue, obesity, type 2 diabetes

  13. Blood Volume, Plasma Volume and Circulation Time in a High-Energy-Demand Teleost, the Yellowfin Tuna (Thunnus Albacares)

    DEFF Research Database (Denmark)

    Brill, R.W.; Cousins, K.L.; Jones, D.R.

    1998-01-01

    We measured red cell space with 51Cr-labeled red blood cells, and dextran space with 500 kDa fluorescein-isothiocyanate-labeled dextran (FITC-dextran), in two groups of yellowfin tuna (Thunnus albacares). Red cell space was 13.8+/-0.7 ml kg-1 (mean +/- s.e.m.) Assuming a whole- body hematocrit...... for albacore (Thunnus alalunga, 82-197 ml kg-1). Plasma volume within the primary circulatory system (calculated from the 51Cr-labeled red blood cell data) was 32.9+/-2.3 ml kg-1. Dextran space was 37.0+/-3.7 ml kg-1. Because 500 kDa FITC-dextran appeared to remain within the vascular space, these data imply...

  14. Report of Didymocystis wedli Ariola, 1902 (Digenea; Didymozoidae from Thunnus albacares in Brazil

    Directory of Open Access Journals (Sweden)

    A Kohn

    2001-10-01

    Full Text Available Didymocystis wedli a parasite from the gills of Thunnus albacares from the coast of the State of Rio de Janeiro, is described by use of light and scanning electron microscopy. This is the first report of this species in Brazil and South America. New data are presented on the surface topography as demonstrated by scanning electron microscopy.

  15. Complete mitochondrial genome of the whitetip reef shark Triaenodon obesus (Carcharhiniformes: Carcharhinidae).

    Science.gov (United States)

    Chen, Xiao; Sonchaeng, Pichai; Yuvanatemiya, Vasin; Nuangsaeng, Bunlung; Ai, Weiming

    2016-01-01

    The complete mitochondrial genome of the whitetip reef shark Triaenodon obesus is determined in this study. It is 16,700 bp in length, with the typical gene composition, arrangement and transcriptional orientation in vertebrates. The overall base composition is 31.4% A, 25.8% C, 13.2% G and 29.7% T. Two start codons and two stop codons are found in the protein-coding genes. The 22 tRNA genes ranged from 67 to 75 nucleotides. The tRNA-Ser2 lost the DHU arm and could not be folded to the typical cloverleaf secondary structure. The origin of L-strand replication (OL) sequence was identified between tRNA-Asn and tRNA-Cys genes. The high A+T content of control region is due to a lot of poly A and poly T.

  16. EMBRYO DEVELOPMENT OF YELLOWFIN TUNA (Thunnus albacares AT DIFFERENT INCUBATION TEMPERATURE

    Directory of Open Access Journals (Sweden)

    Jhon Harianto Hutapea

    2007-12-01

    Full Text Available The experiment was conducted in order to figure out the effect of incubation temperature on embryonic development of yellowfin tuna, Thunnus albacares eggs. Five different incubation temperatures were applied as treatments, i.e.: 24°C, 26°C, 28°C, 30°C, and 32°C with 3 replicate each. Ten micro plates with lid (IWAKI, Japan were used; each has 6 well and 10 mL volumes. Five micro plates were used for experiment and five for balance on shaker. Three well of each micro plate were filled with 8 mL ultra violet sterilized sea water and 50 fertilized eggs. Temperature was set using Multi Thermo Incubator which has 5 level racks. Temperatures were set from the lowest to the highest on bottom to upper rack order. To maintain eggs dispersed in the medium, shaker on each rack was operated at 150 RPM. The embryo was monitored every 30-60 minutes depends on embryonic stage development using Microscope which was connected to Digital Camera DXM 1200F. Image analyses by Image Analyzer Program. The results showed, incubation temperature was significantly affect (P<0.05 embryonic development and hatching time of yellowfin tuna (Thunnus albacares eggs. Optimum incubation temperature for embryo development and hatching was 28°C. Decreased on incubation temperature slows down embryo development at all stages, and vice versa, increased on incubation temperature accelerates embryo development.

  17. Antitermite Activities of C. decidua Extracts and Pure Compounds against Indian White Termite Odontotermes obesus (Isoptera: Odontotermitidae

    Directory of Open Access Journals (Sweden)

    Ravi Kant Upadhyay

    2012-01-01

    Full Text Available In the present investigation, we have tested antitermite responses of Capparis decidua stem, root, flower, and fruit extracts and pure compounds to Odontotermes obesus in various bioassays. Crude stem extract has shown very high susceptibility and very low LD50 values, that is, 14.171 μg/mg in worker termites. From stem extract, three pure compounds were isolated in pure form namely, heneicosylhexadecanoate (CDS2, triacontanol (CDS3, and 2-carboxy-1, 1-dimethylpyrrolidine (CDS8 which have shown very low LD50 value in a range of 5.537–10.083 μg/mg. Similarly, one novel compound 6-(1-hydroxy-non-3-enyl-tetrahydropyran-2-one (CDF1 was isolated from flower extract that has shown an LD50 8.08 μg/gm. Repellent action of compounds was tested in a Y-shaped glass olfactometer in which CDF1 compounds have significantly repelled termites to the opposite arm. Besides this, C. decidua extracts have shown significant reduction (P<0.05 and 0.01 in termite infestation in garden saplings when it was coated on cotton tags and employed over tree trunks. Further, C. deciduas stem extract was used for wood seasoning, which gave very good results as test wood sticks have shown significantly (P<0.05 and 0.01 very low termite infestation.

  18. STOMACH CONTENT OF THREE TUNA SPECIES IN THE EASTERN INDIAN OCEAN

    Directory of Open Access Journals (Sweden)

    Bram Setyadji

    2012-12-01

    Full Text Available Feeding habit of tuna in Indian Ocean has been described around Sri Lanka, Indian Waters, Andaman Sea, western Indian Ocean (Seychelles Islands, western equatorial Indian Ocean whereas the tunas feeding habit study in Eastern Indian Oceanis merely in existence. The purpose of this study is to investigate the stomach content of three tuna species (bigeye tuna, yellowfin tuna, and skipjack tuna, apex predator in the southern part of Eastern Indian Ocean. The study was conducted in March – April, 2010 on the basis of catches of commercial tuna longline vessel based in Port of Benoa. A total of 53 individual fishes were collected, consisting of bigeye tuna (Thunnus obesus, yellowfin tuna (Thunnus albacores, and skipjack tuna (Katsuwonus pelamis. Stomach specimens were collected and analyzed.Analysis was conducted on the basis of index of preponderance method. The diet of the three tuna species showed fishes as the main diet (56–82%, followed by cephalopods (squids as the complementary diet (0–8%, and crustaceans (shrimps as the additional diet (2–4%. Fish prey composed of 6 families i.e. Alepisauridae, Bramidae, Carangidae, Clupeidae, Engraulidae, and Scombridae.

  19. A validated methodology for genetic identification of tuna species (genus Thunnus.

    Directory of Open Access Journals (Sweden)

    Jordi Viñas

    2009-10-01

    Full Text Available Tuna species of the genus Thunnus, such as the bluefin tunas, are some of the most important and yet most endangered trade fish in the world. Identification of these species in traded forms, however, may be difficult depending on the presentation of the products, which may hamper conservation efforts on trade control. In this paper, we validated a genetic methodology that can fully distinguish between the eight Thunnus species from any kind of processed tissue.After testing several genetic markers, a complete discrimination of the eight tuna species was achieved using Forensically Informative Nucleotide Sequencing based primarily on the sequence variability of the hypervariable genetic marker mitochondrial DNA control region (mtDNA CR, followed, in some specific cases, by a second validation by a nuclear marker rDNA first internal transcribed spacer (ITS1. This methodology was able to distinguish all tuna species, including those belonging to the subgenus Neothunnus that are very closely related, and in consequence can not be differentiated with other genetic markers of lower variability. This methodology also took into consideration the presence of introgression that has been reported in past studies between T. thynnus, T. orientalis and T. alalunga. Finally, we applied the methodology to cross-check the species identity of 26 processed tuna samples.Using the combination of two genetic markers, one mitochondrial and another nuclear, allows a full discrimination between all eight tuna species. Unexpectedly, the genetic marker traditionally used for DNA barcoding, cytochrome oxidase 1, could not differentiate all species, thus its use as a genetic marker for tuna species identification is questioned.

  20. Polimorfisme Enzim Glucose-6-Phosphate Isomerase pada Tiga Populasi Tuna Sirip Kuning (Thunnus albacares)

    OpenAIRE

    Permana, Gusti Ngurah; Hutapea, Jhon H.; Moria, Sari Budi; Haryanti, Haryanti

    2006-01-01

    Samples of yellowfin tuna (Thunnus albacares) were taken from three locations Bali, North Sulawesi and North Maluku. The glucose-6-phosphate isomerase (GPI) was analyzed from liver using allozyme electrophoresis method. Polymorphism of GPI enzyme was observed and four alleles (A, B ,C, D) were found in Bali population, three alleles (A,B,C) were found in North Maluku and North Sulawesi populations. Heterozygosity values, from Bali, North Maluku and North Sulawesi were 0.419; 0.417; 0.143 resp...

  1. Molecular and morphological identification of Cardicola (Trematoda: Aporocotylidae) eggs in hatchery-reared and migratory Atlantic bluefin tuna (Thunnus thynnus L.)

    Czech Academy of Sciences Publication Activity Database

    Forte-Gil, D.; Holzer, Astrid S.; Pecková, Hana; Bartošová-Sojková, Pavla; Peñalver, J.; Dolores, E.M.; Muñoz, P.

    2016-01-01

    Roč. 450, JAN 1 (2016), s. 58-66 ISSN 0044-8486 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : Aquaculture * Atlantic bluefin tuna * Blood fluke * Cardicola * Migration * Thunnus thynnus Subject RIV: EG - Zoology Impact factor: 2.570, year: 2016

  2. Validation of the method spectrophotometer in the histamine determination in fresh tuna (Thunnus Tunna)

    International Nuclear Information System (INIS)

    Chacon Silva, F.

    1998-01-01

    The objective of this study was to validate the spectrophotometer method described by Bateman et al. (1994) for the histamine determination in fresh tuna (Thunnus Tunna) and to evaluate the histamine concentration in samples of fresh tuna. To fulfill the recently exposed objectives, the figures of merit were determined like they are it: recovery limits of detection, sensibility and repetitive of the method spectrophotometry and applied the analysis at twenty samples of fresh tuna for copy of the Metropolitan area and three sample like reference of fresh tuna stored 4 degree centigrade by 15 days. The histamine recovery you determines enriching seven ours of fresh tuna with histamine to two levels different 0.613 mg/L and 2.21 mg/L. three samples were left without enriching and you subtract the average to the native histamine. You determines the one it limits of detection using the standard deviation to three levels of concentration of histamine 1.37 mg/L, 2.22 mg/L and 3.22 mg/L, the minimum quantity of hi stamina that you can determine for the method spectrophotometry settling down. The repetitive you determines using the standard deviation for 100 among the average of the histamine values, in seven you replies independent of the same sample. You determines the histamine content, in the fresh tuna Thunnus Tunna of the expends of the Metropolitan Area and in samples of reference stored 4 degrees centigrade by 15 days [es

  3. Mercury in tunas and blue marlin in the North Pacific Ocean.

    Science.gov (United States)

    Drevnick, Paul E; Brooks, Barbara A

    2017-05-01

    Models and data from the North Pacific Ocean indicate that mercury concentrations in water and biota are increasing in response to (global or hemispheric) anthropogenic mercury releases. In the present study, we provide an updated record of mercury in yellowfin tuna (Thunnus albacares) caught near Hawaii that confirms an earlier conclusion that mercury concentrations in these fish are increasing at a rate similar to that observed in waters shallower than 1000 m. We also compiled and reanalyzed data from bigeye tuna (Thunnus obesus) and blue marlin (Makaira nigricans) caught near Hawaii in the 1970s and 2000s. Increases in mercury concentrations in bigeye tuna are consistent with the trend found in yellowfin tuna, in both timing and magnitude. The data available for blue marlin do not allow for a fair comparison among years, because mercury concentrations differ between sexes for this species, and sex was identified (or reported) in only 3 of 7 studies. Also, mercury concentrations in blue marlin may be insensitive to modest changes in mercury exposure, because this species appears to have the ability to detoxify mercury. The North Pacific Ocean is a region of both relatively high rates of atmospheric mercury deposition and capture fisheries production. Other data sets that allow temporal comparisons in mercury concentrations, such as pacific cod (Gadus macrocephalus) in Alaskan waters and albacore tuna (Thunnus alalunga) off the US Pacific coast, should be explored further, to aid in understanding human health and ecological risks and to develop additional baseline knowledge for assessing changes in a region expected to respond strongly to reductions in anthropogenic mercury emissions. Environ Toxicol Chem 2017;36:1365-1374. © 2017 SETAC. © 2017 SETAC.

  4. Influences of oceanographic features on the distribution and abundance of yellowfin tuna, Thunnus albacares, larvae in the Gulf of Mexico

    Science.gov (United States)

    Cornic, M.; Rooker, J. R.

    2016-02-01

    Summer ichthyoplankton surveys were conducted in the northern Gulf of Mexico (NGoM) from 2007-2010 to characterize patterns of distribution and abundance of yellowfin tuna (Thunnus albacares) larvae in this region. Yellowfin tuna larvae were moderately abundant representing 9% of the overall Thunnus larvae collected (18765) and had a percent occurrence ranging from 13 to 57% among surveys. Interannual variations were detected with highest mean densities observed in 2009 (2.2 larvae per 1000m3) and the lowest mean densities observed in 2008 (0.7 larvae per 1000 m3). Generalized additive models were used to investigate the influence of oceanographic conditions on abundance of yellowfin tuna larvae. Increased densities were associated with high sea surface temperatures, positive sea surface heights, and intermediate salinities, revealing that these physicochemical conditions may be favorable for yellowfin tuna larvae. These results indicate that the NGoM is an important spawning and/or nursery habitat for yellowfin tuna and suggest that mesoscale features and physicochemical characteristics of water masses may impact distribution and abundance of yellowfin tuna larvae in the NGoM.

  5. Morphometric analysis of population samples of soldier caste of Odontotermes obesus (Rambur (Isoptera, Termitidae, Macrotermitinae

    Directory of Open Access Journals (Sweden)

    Manzoor, F.

    2006-12-01

    Full Text Available In order to study morphometric variations in Odontotermes obesus (Rambur, samples from nineteen nests were statistically analyzed for mean, standard deviation, standard error, coefficient of variability and confidence interval (95% and analysis of variance (Model II ANOVA, The mean values of the different population samples were compared with the student t-test, following the Minitab version and Sokal & Rohlf (1973. In the study of external characters, measurements form a very important component, particularly for identification of species. However, the reliability of the measurements depends on the extent of variability which the structures show within and between colonies. For each individual soldier, the following nine parameters were measured: i length of head; ii width of head at mandibles; iii width of head at the posterolateral ends of antennal carinae; iv maximum width of head; v length of left mandible; vi tooth of left mandible from tip; vii length of pronotum; viii width of pronotum; ix length of postmentum; and x width of postmentum.

  6. Antigenicity of Anisakis simplex s.s. L3 in parasitized fish after heating conditions used in the canning processing.

    Science.gov (United States)

    Tejada, Margarita; Olivares, Fabiola; de las Heras, Cristina; Careche, Mercedes; Solas, María Teresa; García, María Luisa; Fernandez, Agustín; Mendizábal, Angel; Navas, Alfonso; Rodríguez-Mahillo, Ana Isabel; González-Muñoz, Miguel

    2015-03-30

    Some technological and food processing treatments applied to parasitized fish kill the Anisakis larvae and prevent infection and sensitization of consumers. However, residual allergenic activity of parasite allergens has been shown. The aim here was to study the effect of different heat treatments used in the fish canning processing industry on the antigen recognition of Anisakis L3. Bigeye tuna (Thunnus obesus) and yellowfin tuna (Thunnus albacares) were experimentally infected with live L3 Anisakis. After 48 h at 5 ± 1 °C, brine was added to the muscle, which was then canned raw (live larvae) or heated (90 °C, 30 min) (dead larvae) and treated at 113 °C for 60 min or at 115 °C for 90 min. Anisakis antigens and Ani s 4 were detected with anti-crude extract and anti-Ani s 4 antisera respectively. Ani s 4 decreased in all lots, but the muscle retained part of the allergenicity irrespective of the canning method, as observed by immunohistochemistry. Dot blot analysis showed a high loss of Ani s 4 recognition after canning, but residual antigenicity was present. The results indicate that heat treatment for sterilization under the conditions studied produces a decrease in Ani s 4 and suggest a potential exposure risk for Anisakis-sensitized patients. © 2014 Society of Chemical Industry.

  7. β-glycosphingolipids ameliorated non-alcoholic steatohepatitis in the Psammomys obesus model

    Directory of Open Access Journals (Sweden)

    Zigmond E

    2014-10-01

    Full Text Available Ehud Zigmond,1,* Oshrat Tayer-Shifman,1,* Gadi Lalazar,1 Ami Ben Ya'acov,1 Sarah Weksler-Zangen,2 David Shasha,1 Miriam Sklair-Levy,3 Lidya Zolotarov,1 Zvi Shalev,1 Rony Kalman,2 Ehud Ziv,2 Itamar Raz,2 Yaron Ilan1 1Liver Unit, 2Diabetes Unit, 3Department of Radiology, Hebrew University-Hadassah Medical Center, Jerusalem, Israel *These authors contributed equally to this workAbstract: Liver steatosis is a common characteristic of obesity and type 2 diabetes, and fatty liver disease is increasingly recognized as a major health burden. Accumulating evidence suggests that β-glycosphingolipids play an important role in insulin sensitivity and thus could affect hepatic steatosis. To determine the effect associated with β-glycosphingolipid-mediated amelioration of liver injury, seven groups of Psammomys obesus on a high-energy diet were studied. Animals were treated with daily injections of β-glucosylceramide, β-lactosylceramide, or a combination of both. β-glycosphingolipids ameliorated the hepatic injury manifested by decreased liver enzymes, liver weight, and hepatic fat, and improved liver histology. Administration of both β-glucosylceramide and β-lactosylceramide also decreased interferon (IFN-γ serum levels. These effects were associated with improved serum cholesterol and triglyceride levels. These data suggest that β-glycosphingolipids ameliorate liver injury in an animal model of nonalcoholic steatohepatitis.Keywords: NAFLD, glycolipids, STAT, NASH, insulin resistance, diabetes

  8. Keragaman Spesies Ikan Tuna di Pasar Ikan Kedonganan Bali dengan Analisis Sekuen Kontrol Daerah Mitokondria DNA (SPECIES DIVERSITY OF TUNA FISH USING MITOCHONDRIAL DNA CONTROL REGION SEQUENCE ANALYSIS AT KEDONGANAN FISH MARKET

    Directory of Open Access Journals (Sweden)

    Daud Steven Triyomi Hariyanto

    2015-10-01

    Full Text Available Tuna is an export commodity which has very high economic value. However, some tuna speciesare threatened with extinction. The purpose of this study was to identify the tuna species that aresold in Kedonganan Fish Market. The research method was polymerase chain reaction technique(PCR using the marker sequence mitochondrial DNA control region. Samples were obtained fromthe Fish Market tuna Kedonganan, Kuta, Badung, Bali. The total number of samples are 28specimens. Sequence from each sample was obtained through sequencing techniques. Sequencesobtained were run in BLAST (Basic Local Alignment Search Tool and subsequently analyzed withMEGA 5 for species confirmation. Three species of tuna that are identified in the Kedonganan FishMarket is: Thunnus albacares, T. obesus, and Katsuwonus pelamis. All three species have highgenetic variation HD = 1. This study needed to be continued with more number of samples todetermine the species of tuna sold in Kedonganan Fish Market.

  9. Relative growth pattern and hard tissue of vertebral centra by microradiography of bluefin tuna

    International Nuclear Information System (INIS)

    Kubo, Y.; Asano, H.

    1989-01-01

    To clarify the growth feature and the structure of hard tissue, we studied the vertebral centrum of three species, bluefin tuna Thunnus thynnus, bigeye tuna T. obesus and skipjack Katsuwonus pelamis (BL: 44.2, 39.5 and 40.0cm respectively). We examined the ratio of cetrum length to diameter in each vertebral centrum and obtained the value of 0.9-1.3 in most centra among three species. This indicates that the examined species belong to the equivalent type of the relative growth pattern of vertebral centra. The hard tissue was observed by microradiography, with the longitudinal and cross sections (about 100 μm) cut through the center of notochordal pore. The major centra of the vertebral column were composed of characteristic simple structure like a cross, when seen in the microradiographs of cross sections. Microradiographs indicated that the bone has complicated canals with minute spaces like the bone cavities

  10. Pathological manifestation of the Acanthocephalus dirus in Thunnus albacares

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    Alagarsamy Sakthivel

    2016-05-01

    Full Text Available Objective: To describe the pathological manifestation of the Acanthocephalus dirus (A. dirus infestation in Thunnus albacares (T. albacares from southeast coast of India. Methods: The parasite-infested fishes were collected from Nagapattinam landing centre of Tamil Nadu from southeast coast of India. The Acanthocephala morphology, gross pathology, histopathology and histochemistry were investigated. Results: T. albacares were severely infested with A. dirus, the group of Acanthocephala attached to the posterior region of the intestine. The adult worm proboscis was cylindrical and the length and width ranging between 2.7–6.4 mm and 0.8–1.3 mm, respectively. Histopathologically, the infested intestinal mucosal epithelium, stratum granulosum, lamina propria, muscular and serosa layers were highly degraded. The lesions were infiltrating with basophil-like inflammatory cells. The parasite-affected lesions were histochemically positive for alcian blue, azo dye, toluidine blue and oil red O. Conclusions: This is the new host for the parasite A. dirus in T. albacares. On the basis of histological and histochemical findings, the lesions were highly damaged due to the parasitic infestation. The high density of the parasite and severe penetration of the proboscis into the intestinal tissues are the main reason for the pathogenicity in the host.

  11. Uso de hábitat de Triaenodon obesus (Carcharhiniformes: Carcharhinidae, Rhincodon typus (Orectolobiformes: Rhincodontidae y Manta birostris (Myliobatiformes: Myliobatidae en el Parque Nacional Natural Gorgona, Pacífico colombiano

    Directory of Open Access Journals (Sweden)

    Paola Andrea Mejía-Falla

    2014-02-01

    Full Text Available Se evaluó el uso de hábitat del aletiblanco Triaenodon obesus, la mantaraya Manta birostris y el tiburón ballena Rhincodon typus en la Isla Gorgona, a partir de 427 inmersiones de buceo y del análisis de 866 fotografías y videos. T. obesus se observó a lo largo del año, y su presencia se correlacionó con profundidades entre 20 y 30m (66.9%, fondos areno-rocosos (79.8% y las zonas occidental (61.2% y sur (52.9%, con mayores congregaciones en esta última zona. R. typus y M. birostris se avistaron entre 28 y 33oC y su presencia se correlacionó con la zona norte de la isla, área de mayor abundancia de zoo e ictioplancton. Se identificaron 5 tiburones ballena, 15 mantarrayas y 38 aletiblancos, 9 de los cuales fueron recapturados en años diferentes. La mayoría de los aletiblancos recapturados fueron observados solos, en reposo y sobre el fondo y en la misma zona, sugiriendo alta filopatría; sin embargo, la recaptura de tres individuos en zonas diferentes, indican conectividad de la especie en la isla. Gorgona es un área importante para la reproducción y crecimiento del aletiblanco, y un área de paso para el tiburón ballena y la mantarraya, los cuales se observan con mayor frecuencia entre marzo y septiembre, pero no forman agregaciones.

  12. Atlantic Bluefin Tuna (Thunnus thynnus) Biometrics and Condition.

    Science.gov (United States)

    Rodriguez-Marin, Enrique; Ortiz, Mauricio; Ortiz de Urbina, José María; Quelle, Pablo; Walter, John; Abid, Noureddine; Addis, Piero; Alot, Enrique; Andrushchenko, Irene; Deguara, Simeon; Di Natale, Antonio; Gatt, Mark; Golet, Walter; Karakulak, Saadet; Kimoto, Ai; Macias, David; Saber, Samar; Santos, Miguel Neves; Zarrad, Rafik

    2015-01-01

    The compiled data for this study represents the first Atlantic and Mediterranean-wide effort to pool all available biometric data for Atlantic bluefin tuna (Thunnus thynnus) with the collaboration of many countries and scientific groups. Biometric relationships were based on an extensive sampling (over 140,000 fish sampled), covering most of the fishing areas for this species in the North Atlantic Ocean and Mediterranean Sea. Sensitivity analyses were carried out to evaluate the representativeness of sampling and explore the most adequate procedure to fit the weight-length relationship (WLR). The selected model for the WLRs by stock included standardized data series (common measurement types) weighted by the inverse variability. There was little difference between annual stock-specific round weight-straight fork length relationships, with an overall difference of 6% in weight. The predicted weight by month was estimated as an additional component in the exponent of the weight-length function. The analyses of monthly variations of fish condition by stock, maturity state and geographic area reflect annual cycles of spawning and feeding behavior. We update and improve upon the biometric relationships for bluefin currently used by the International Commission for the Conservation of Atlantic Tunas, by incorporating substantially larger datasets than ever previously compiled, providing complete documentation of sources and employing robust statistical fitting. WLRs and other conversion factors estimated in this study differ from the ones used in previous bluefin stock assessments.

  13. Heavy metals in yellowfin tuna (Thunnus albacares) and common dolphinfish (Coryphaena hippurus) landed on the Ecuadorian coast

    Energy Technology Data Exchange (ETDEWEB)

    Araújo, Cristiano V.M., E-mail: cristiano.araujo@icman.csic.es [Central Department of Research (DCI), Ecuadorian Aquatic Ecotoxicology (ECUACTOX) group, Universidad Laica Eloy Alfaro de Manabí - ULEAM, Manta (Ecuador); Centre of Functional Ecology (CFE), Department of Life Sciences, University of Coimbra, Coimbra (Portugal); Cedeño-Macias, Luis A. [Central Department of Research (DCI), Ecuadorian Aquatic Ecotoxicology (ECUACTOX) group, Universidad Laica Eloy Alfaro de Manabí - ULEAM, Manta (Ecuador); Faculty of Marine Sciences, Universidad Laica Eloy Alfaro de Manabí (ULEAM), Manta (Ecuador)

    2016-01-15

    Heavy metals are contaminants of great environmental concern due to their multiple origins (natural and anthropogenic), the ability to accumulate in organs and tissues, and the deleterious effects they can cause in organisms. Studies on the accumulation of metals in seafood, such as fish, have increased in importance due to the risk for human health when consuming fish contaminated by metals. The present work was aimed at verifying the concentrations of cadmium (Cd), mercury (Hg) and lead (Pb) in the muscular tissue and liver of yellowfin tuna (Thunnus albacares) and common dolphinfish (Coryphaena hippurus) from the Eastern Pacific Ocean landed in Manta city, Ecuador. Samples were analyzed by inductively coupled plasma mass spectroscopy (ICP-MS). Around half of the muscle samples of both species presented levels of Cd and Hg above the limits considered safe for human consumption established by the European Union. For Pb, most of the muscle samples were considered acceptable for consumption. Results indicate that both species should be consumed with some caution. Considering the tolerable weekly intake recommended for adults by the World Health Organization, results indicate that Hg is the main metal that limits the consumption of yellowfin tuna and common dolphinfish, with a recommended maximum ingestion, respectively, of 191 and 178 g per week for an adult. - Highlights: • Thunnus albacares and Coryphaena hippurus from Eastern Pacific (Ecuador) were sampled. • Muscle and liver of both species were assessed for Cd, Hg and Pb concentrations. • Levels of Pb were considered acceptable for both species. • High levels of Cd and Hg in both species can be considered unsafe for human health. • For both species the recommended maximum ingestion is around 180 g week{sup −1} for an adult.

  14. Del cultivo basado en capturas, a la acuicultura independiente y la domesticación del atún rojo, Thunnus thynnus. Principales resultados, conclusiones y recomendaciones del Proyecto SELFDOTT

    OpenAIRE

    de-la-Gándara, F. (Fernando)

    2012-01-01

    Principales resultados, conclusiones y recomendaciones del Proyecto SELFDOTT (Del cultivo basado en capturas, a la acuicultura independiente y la domesticación del atún rojo, Thunnus thynnus.) Comisión Europea 7º PM (KBBE-2007-1-2-09 Cooperation Work Programme: Food, Agriculture and Fisheries, and Biotechnology), Versión de editor 0

  15. La flexión de la notocorda en larvas de atún rojo, Thunnus thynnus (L, 1758) cultivadas a diferentes temperaturas

    OpenAIRE

    de-la-Gándara, F. (Fernando); Ortega-García, A. (Aurelio); Blanco, E. (Edurne); Viguri, F.J. (Francisco Javier); Reglero, P. (Patricia)

    2013-01-01

    Se ha estudiado el desarrollo ontogénico de las larvas de atún rojo, Thunnus thynnus, especialmente el momento de la flexión de la notocorda y su relación con la temperatura. El cultivo larvario se ha realizado en tanques replicados en un medio controlado. Los resultados contribuyen a mejorar el conocimiento existente sobre el desarrollo larvario del atún rojo en la naturaleza. Este trabajo se ha realizado en el marco del proyecto ATAME-IEO (Plan Nacional de I+D+i 2008-2011).

  16. PENGARUH PERENDAMAN TULANG IKAN TUNA (Thunnus albacares DALAM LARUTAN NaOH TERHADAP KUALITAS GELATIN HASIL OLAHANNYA

    Directory of Open Access Journals (Sweden)

    Tazwir Tazwir

    2009-06-01

    Full Text Available Gelatin tulang ikan tuna (Thunnus albaceres dengan kualitas baik seringkali sulit diperoleh, karena kebanyakan produk ini mengandung lemak dan protein non kolagen yang cukup tinggi. Dalam memproduksi gelatin tulang tuna, lemak, dan protein non kolagen tersebut harus direduksi hingga batas minimum. Dalam penelitian ini dipelajari pengaruh perendaman tulang ikan tuna dalam larutan NaOH sebelum ekstraksi terhadap kualitas gelatin yang dihasilkan. Tahapan yang dilakukan adalah degreasing, pencucian, perendaman dalam NaOH dengan variasi konsentrasi 0; 0,4; dan 0,8%, kemudian perendaman dalam HCl, ekstraksi, filtrasi, evaporasi, dan pengeringan. Hasil penelitian menunjukkan bahwa karakteristik gelatin yang terbaik diperoleh dari perendaman tulang dalam NaOH 0,4%, yaitu dengan nilai rendemen 8,37%; viskositas 3,27-3,37 cPs; pH 5,03; dan kekuatan gel 157,8 g Bloom gel strength.

  17. Discovering where bluefin tuna, Thunnus thynnus, might go: using environmental and fishery data to map potential tuna habitat in the eastern Mediterranean Sea

    OpenAIRE

    Dimitrios Damalas; Persefoni Megalofonou

    2012-01-01

    Based on a dataset derived from commercial fisheries in the eastern Mediterranean Sea in 1998-2005, we applied generalized additive models (GAMs) to investigate the relative influence of a range of environmental factors on catch rates of Atlantic bluefin tuna (Thunnus thynnus Linnaeus, 1785). GAM analyses were conducted by separately modelling (1) the probability of making a catch (encountering a school), and (2) the positive catch rates (school size). Results suggested intra-annual variation...

  18. Heavy metals in fish tissues/stomach contents in four marine wild commercially valuable fish species from the western continental shelf of South China Sea.

    Science.gov (United States)

    Gu, Yang-Guang; Lin, Qin; Huang, Hong-Hui; Wang, Liang-Gen; Ning, Jia-Jia; Du, Fei-Yan

    2017-01-30

    The concentrations of heavy metals (Cd, Pb, Cr, Ni, Cu and Zn) were determined in four commercially valuable fish species (Thunnus obesus, Decapterus lajang, Cubiceps squamiceps and Priacanthus macracanthus), collected in the western continental shelf of the South China Sea. Concentrations of Cd, Pb, Cr, Ni, Cu, and Zn in fish muscles were 0.006-0.050, 0.13-0.68, 0.18-0.85, 0.11-0.25, 0.12-0.77, and 2.41-4.73μg/g, wet weight, respectively. Concentrations of heavy metals in all species were below their acceptable daily upper limit, suggesting human consumption of these wild fish species may be safe, with health risk assessment based on the target hazard quotients (THQ) and total THQ, indicating no significant adverse health effects with consumption. The average concentrations of Zn were higher in gills than in stomach contents, backbones or muscle, while conversely, the other heavy metals had higher concentrations in stomach contents than in other tissues. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Extracting of yellowfin tuna (Thunnus albacares) fish skin gelatin as influenced by alkaline concentration and extraction times

    Science.gov (United States)

    Mafazah, E. M.; Pranoto, Y.; Rohman, A.

    2018-03-01

    Yellowfin tuna (Thunnus albacares) skin is a by-product of the fish processing industry. Yellowfin tuna skin was used as materials for gelatin because it contains collagen. This study was conducted to determine the characteristics of yellowfin tuna skin gelatin (YSG). In this study, YSG was obtained by the extraction process in 0.01 M NaOH solution for 12 h. The results show that the yield of YSG was 12.49 % dry basis, with the gel strength of 291.73 g Bloom, viscosity of 8.6 cPs and melting point of 35 °C. The gel strength and melting point of YSG were lower than commercial bovine gelatin (CBG), which was 309.7401 g Bloom and 36.33 °C, respectively. However, the viscosity of YSG was higher than the CBG which was 5.6 cPs.

  20. The development of the northern European fishery for north Atlantic bluefin tuna Thunnus thynnus during 1900-1950

    DEFF Research Database (Denmark)

    MacKenzie, Brian; Myers, R.A.

    2007-01-01

    North Atlantic bluefin tuna, Thunnus thynnus, used to migrate to northern European waters (Norwegian Sea, North Sea, Skagerrak, Kattegat, and Øresund) where it supported important commercial and sportfisheries. The species disappeared from the region in the early 1960s and the species is now still...... increasing. The species was frequently sighted while fishermen were targeting other species (herring, mackerel) and occasionally was caught as bycatch with these and other species. Information from scientifically trained observers demonstrate that tuna schools were common in the North Sea for 2–3 months...... during the summers of 1923–1931. As fishermen realized that the species had market value, new catch methods were developed and employed. These included harpoon-rifle, improved hook and line methods, and hydraulically operated purse seines. Landings rose sharply as did the number of vessels...

  1. Preliminary approach on early post mortem stress and quality indexes changes in large size bluefin tuna (Thunnus thynnus

    Directory of Open Access Journals (Sweden)

    R. Ugolini

    2010-01-01

    Full Text Available Bluefin tuna (Thunnus thynnus is very appreciated on Japan and USA market for the preparation of sushi and sahimi. The market price of the fresh product can vary from 8 to 33 Euro/kg (gate farm/producers prices according to size, shape, fat level, meat colour, consistency and freshness (absence of “hyake”, all parameters strictly connected to feeding quality and quantity, rearing and killing stress factors and refrigeration times and conditions after death. Excessive levels of stress during the slaughtering can affect meat quality, contributing to significantly decrease of tuna’s price. The present trial was carried out to evaluate the possible harvesting/slaughtering stress effect on reared bluefin tuna meat quality, starting from the examination of the most important stress and quality parameters changes during the early post mortem period.

  2. Molecular Identification of Atlantic Bluefin Tuna (Thunnus thynnus, Scombridae Larvae and Development of a DNA Character-Based Identification Key for Mediterranean Scombrids.

    Directory of Open Access Journals (Sweden)

    Gregory Neils Puncher

    Full Text Available The Atlantic bluefin tuna, Thunnus thynnus, is a commercially important species that has been severely over-exploited in the recent past. Although the eastern Atlantic and Mediterranean stock is now showing signs of recovery, its current status remains very uncertain and as a consequence their recovery is dependent upon severe management informed by rigorous scientific research. Monitoring of early life history stages can inform decision makers about the health of the species based upon recruitment and survival rates. Misidentification of fish larvae and eggs can lead to inaccurate estimates of stock biomass and productivity which can trigger demands for increased quotas and unsound management conclusions. Herein we used a molecular approach employing mitochondrial and nuclear genes (CO1 and ITS1, respectively to identify larvae (n = 188 collected from three spawning areas in the Mediterranean Sea by different institutions working with a regional fisheries management organization. Several techniques were used to analyze the genetic sequences (sequence alignments using search algorithms, neighbour joining trees, and a genetic character-based identification key and an extensive comparison of the results is presented. During this process various inaccuracies in related publications and online databases were uncovered. Our results reveal important differences in the accuracy of the taxonomic identifications carried out by different ichthyoplanktologists following morphology-based methods. While less than half of larvae provided were bluefin tuna, other dominant taxa were bullet tuna (Auxis rochei, albacore (Thunnus alalunga and little tunny (Euthynnus alletteratus. We advocate an expansion of expertise for a new generation of morphology-based taxonomists, increased dialogue between morphology-based and molecular taxonomists and increased scrutiny of public sequence databases.

  3. First data on growth and nucleic acid and protein content of field-captured Mediterranean bluefin (Thunnus thynnus and albacore (Thunnus alalunga tuna larvae: a comparative study

    Directory of Open Access Journals (Sweden)

    Alberto García

    2006-10-01

    Full Text Available The waters surrounding the Balearic archipelago are considered to be prime spawning habitats of the bluefin tuna (Thunnus thynnus and other tuna species such as albacore (T. alalunga in the Mediterranean. During the 2003 bluefin and albacore spawning season, a tuna larval survey (TUNIBAL 0703 was carried out to assess the distribution of bluefin larvae in relation to hydrographic mesoscale features. Tuna larvae were collected by means of surface plankton tows with a bongo gear with a quadrangular mouth measuring 1 m diagonally. The otolith microstructure of 157 and 71 field-captured larvae of Mediterranean bluefin and albacore, respectively, were analyzed to estimate the daily growth pattern. Furthermore, biochemical analysis to estimate DNA, RNA and protein content was done on another batch of 114 bluefin and 132 albacore larvae. The size range included pre-flexion to post-flexion larvae, from 2.8 to 8.6 mm in body length. bluefin and albacore larvae grew linearly in standard length (0.35 and 0.33 mm/day, respectively and potentially with respect to dry weight. No significant differences between species were observed in the size-weight relationship, or in the allometric relationship of body size and weight to otolith radius. However, the relationship of DNA and RNA to body size and weight showed a significant difference between species. Bluefin tuna larvae showed a greater nucleic acid content than albacore larvae. Protein content showed no significant differences with respect to body length.

  4. SEBARAN HASIL TANGKAPAN MADIDIHANG (Thunnus albacares Bonnaterre, 1788 DI SAMUDERA HINDIA BAGIAN TIMUR

    Directory of Open Access Journals (Sweden)

    Arief Wujdi

    2015-06-01

    Full Text Available Ikan Madidihang (Thunnus albacares Bobbaterre, 1788 merupakan salah satu komoditaspenting bagi industri perikanan di Indonesia dimana hasil tangkapannya merupakan yang tertinggi dibandingkan jenis tuna lainnya. Saat ini, kondisi stok madidihang berada dalam kondisi yang baik. Namun, untuk menjaga kelangsungan pemantaatan stok ikan tuna, diperlukan upaya pengelolaan sumber daya tuna. Penelitian ini bertujuan untuk mengetahui distribusi laju tangkap madidihang di Samudera Hindia Bagian Timur. Pengumpulan data dilakukan oleh pemantau ilmiah pada kapal rawai tuna komersial yang berbasis di Benoa, Pelabuhanratu dan Bungus dari Agustus 2005 sampai Desember 2013; serta program monitoring pendaratan tuna yang berbasis di Benoa tahun 2010-2013. Hasil penelitian menunjukkan bahwa laju pancing bervariasi secara bulanan dan tahunan. Rata-rata bulanan laju pancing tertinggi terjadi pada Mei (0,17 ekor/100 pancing dan terendah pada Februari (0,01 ekor/100 pancing, sedangkan rata-rata laju pancing tahunan tertinggi pada 2006 (0,11 ekor/100 pancing dan terendah pada 2011 (0,06 ekor/100 pancing. Rata-rata laju pancing tahunan cenderung mengalami penurunan sebesar 29,48%/ tahun. Ikan madidihang tertangkap oleh rawai tuna Indonesia tersebar dari 0°-34° LS dan 76°-134° BT. Sebaran spasial laju pancing tertinggi berada di sekitar Kepulauan Mentawai dan selatan Jawa Timur hingga Nusa Tenggara. Yellowfin tuna (Thunnus albacares Bobbaterre, 1788 is one of the important commodity for the fishing industry in Indonesia because it has the highest catches compared with other tunas. Nowadays, the yellowfin stock is currently in good condition (not overfished and not subject to overfishing. However, management measure was required to support sustainability of tuna fishery. This study aims to determine the hook rate distribution of yellowfin tuna in the Eastern Indian Ocean. Data was obtained by scientific observers on commercial tuna longline vessels

  5. Radiation induced changes in plasma total protein nitrogen and urinary total nitrogen in desert rodent and albino rats subjected to dietary protein deficiency

    International Nuclear Information System (INIS)

    Roushdy, H.; El-Husseini, M.; Saleh, F.

    1986-01-01

    The effect of gamma-irradiation on plasma total protein nitrogen and urinary total nitrogen was studied in the desert rodent, psammomy obesus obesus and albino rats subjected to dietary protein deficiency. In albino rats kept on high protein diet, the radiation syndrome resulted in urine retention, while in those kept on non-protein diet, such phenomenon was recorded only with the high radiation level of 1170r. Radiation exposure to 780 and 1170r caused remarkable diuresis in psammomys obesus obesus whereas they induced significant urine retention in albino rats. The levels of plasma total protein nitrogen and urinary total nitrogen were higher in albino rats maintained on high protein diet than in those kept on non-protein diet. Radiation exposure caused an initial drop in plasma total protein nitrogen concentration, concomitant with an initial rise in total urinary nitrogen, radiation exposure of psammomys obesus obesus caused significant increase in the levels of plasma protein nitrogen and urinary total nitrogen. Psammomys obesus obesus seemed to be more affected by radiation exposure than did the albino rats

  6. Genomic differentiation and demographic histories of Atlantic and Indo-Pacific yellowfin tuna (Thunnus albacares) populations.

    Science.gov (United States)

    Barth, J M I; Damerau, M; Matschiner, M; Jentoft, S; Hanel, R

    2017-04-13

    Recent developments in the field of genomics have provided new and powerful insights into population structure and dynamics that are essential for the conservation of biological diversity. As a commercially highly valuable species, the yellowfin tuna (Thunnus albacares) is intensely exploited throughout its distribution in tropical oceans around the world, and is currently classified as near threatened. However, conservation efforts for this species have so far been hampered by limited knowledge of its population structure, due to incongruent results of previous investigations. Here, we use whole-genome sequencing in concert with a draft genome assembly to decipher the global population structure of the yellowfin tuna, and to investigate its demographic history. We detect significant differentiation of Atlantic and Indo-Pacific yellowfin tuna populations as well as the possibility of a third diverged yellowfin tuna group in the Arabian Sea. We further observe evidence for past population expansion as well as asymmetric gene flow from the Indo-Pacific to the Atlantic. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  7. Larval assemblages of large and medium-sized pelagic species in the Straits of Florida

    Science.gov (United States)

    Richardson, David E.; Llopiz, Joel K.; Guigand, Cedric M.; Cowen, Robert K.

    2010-07-01

    Critical gaps in our understanding of the distributions, interactions, life histories and preferred habitats of large and medium-size pelagic fishes severely constrain the implementation of ecosystem-based, spatially structured fisheries management approaches. In particular, spawning distributions and the environmental characteristics associated with the early life stages are poorly documented. In this study, we consider the diversity, assemblages, and associated habitat of the larvae of large and medium-sized pelagic species collected during 2 years of monthly surveys across the Straits of Florida. In total, 36 taxa and 14,295 individuals were collected, with the highest diversity occurring during the summer and in the western, frontal region of the Florida Current. Only a few species (e.g. Thunnus obesus, T. alalunga, Tetrapturus pfluegeri) considered for this study were absent. Small scombrids (e.g. T. atlanticus, Katsuwonus pelamis, Auxis spp.) and gempylids dominated the catch and were orders of magnitude more abundant than many of the rare species (e.g. Thunnus thynnus,Kajikia albida). Both constrained (CCA) and unconstrained (NMDS) multivariate analyses revealed a number of species groupings including: (1) a summer Florida edge assemblage (e.g. Auxis spp., Euthynnus alleterattus, Istiophorus platypterus); (2) a summer offshore assemblage (e.g. Makaira nigricans, T. atlanticus, Ruvettus pretiosus, Lampris guttatus); (3) an ubiquitous assemblage (e.g. K. pelamis, Coryphaena hippurus, Xiphias gladius); and (4) a spring/winter assemblage that was widely dispersed in space (e.g. trachipterids). The primary environmental factors associated with these assemblages were sea-surface temperature (highest in summer-early fall), day length (highest in early summer), thermocline depth (shallowest on the Florida side) and fluorescence (highest on the Florida side). Overall, the results of this study provide insights into how a remarkable diversity of pelagic species

  8. Pelagic cephalopods in the western Indian Ocean: New information from diets of top predators

    Science.gov (United States)

    Ménard, Frédéric; Potier, Michel; Jaquemet, Sébastien; Romanov, Evgeny; Sabatié, Richard; Cherel, Yves

    2013-10-01

    Using a combination of diverse large predatory fishes and one seabird, we collected information on the cephalopod fauna of the western Indian Ocean. We analyzed the stomach contents of 35 fishes representing ten families (Xiphiidae, Istiophoridae, Scombridae, Carangidae, Coryphaenidae, Alepisauridae, Dasyatidae, Carcharhinidae, Alopiidae and Sphyrnidae) and of the sooty tern Onychoprion fuscata of the Mozambique Channel from 2000 to 2010. Both fresh and accumulated beaks were used for identifying cephalopod prey. Cephalopods were important prey for twelve predators; swordfish Xiphias gladius had the highest cephalopod proportion; sooty tern (O. fuscata) and bigeye tuna (Thunnus obesus) had high proportions too. We recovered 23 cephalopod families and identified 38 species. Ten species from four Teuthida families (Ommastrephidae, Onychoteuthidae, Histioteuthidae and Ancistrocheiridae) and two Octopoda families (Argonautidae and Bolitaenidae) occurred very frequently in the stomach contents, while Sepiida were rare. Ommastrephidae were the most cephalopod food sources: the purpleback flying squid Sthenoteuthis oualaniensis was the most prevalent prey by far, Ornithoteuthis volatilis was important for eleven predators and few but large specimens of the neon flying squid Ommastrephes bartramii were recovered in the stomachs of swordfish in the Indian South Subtropical Gyre province only. Predators' groups were identified based on cephalopod prey composition, on depth in which they forage, and on prey size. Surface predators' diets were characterized by lower cephalopod diversity but greater average numbers of cephalopod prey, whereas the deep-dwelling predators (swordfish and bigeye tuna) preyed on larger specimens than surface predators (O. fuscata or yellowfin tunas Thunnus albacares). Our findings emphasized the usefulness of a community of marine predators to gain valuable information on the biology and the distribution of the cephalopod forage fauna that are

  9. Developing a DNA barcode library for perciform fishes in the South China Sea: Species identification, accuracy and cryptic diversity.

    Science.gov (United States)

    Hou, Gang; Chen, Wei-Tao; Lu, Huo-Sheng; Cheng, Fei; Xie, Song-Guang

    2018-01-01

    DNA barcodes were studied for 1,353 specimens representing 272 morphological species belonging to 149 genera and 55 families of Perciformes from the South China Sea (SCS). The average Kimura 2-parameter (K2P) distances within species, genera and families were 0.31%, 8.71% and 14.52%, respectively. A neighbour-joining (NJ) tree, Bayesian inference (BI) and maximum-likelihood (ML) trees and Automatic Barcode Gap Discovery (ABGD) revealed 260, 253 and 259 single-species-representing clusters, respectively. Barcoding gap analysis (BGA) demonstrated that barcode gaps were present for 178 of 187 species analysed with multiple specimens (95.2%), with the minimum interspecific distance to the nearest neighbour larger than the maximum intraspecific distance. A group of three Thunnus species (T. albacares, T. obesus and T. tonggol), a pair of Gerres species (G. oyena and G. japonicus), a pair of Istiblennius species (I. edentulous and I. lineatus) and a pair of Uranoscopus species (U. oligolepis and U. kaianus) were observed with low interspecific distances and overlaps between intra- and interspecific genetic distances. Three species (Apogon ellioti, Naucrates ductor and Psenopsis anomala) showed deep intraspecific divergences and generated two lineages each, suggesting the possibility of cryptic species. Our results demonstrated that DNA barcodes are highly reliable for delineating species of Perciformes in the SCS. The DNA barcode library established in this study will shed light on further research on the diversity of Perciformes in the SCS. © 2017 John Wiley & Sons Ltd.

  10. Diet of larval albacore Thunnus alalunga (Bonnaterre, 1788 off Mallorca Island (NW Mediterranean

    Directory of Open Access Journals (Sweden)

    Ignacio Alberto Catalán

    2007-06-01

    Full Text Available These are the first data on the feeding of larval albacore (Thunnus alalunga Bonnaterre, 1788 in the Mediterranean. Specimens were gathered from day-time bongo-hauls conducted over the SW Mallorcan (Balearic Islands shelf-slope. Ninety eight percent of 101 individuals ranging from 2.65 to 9.4 mm standard length (SL contained 1 to 15 prey items per gut. Mean number of prey/gut was 3.55 ± 2.19 (SD. A positive correlation was found between larval SL and the number of prey/gut. The analysis of frequency of occurrence (F, numerical frequency (N, weight frequency (W and the Index of Relative Importance (IRI showed a dominance of copepodites and nauplii in the smallest size-class. As larvae grew, cladocerans and Calanoida copepodites dominated the diet, and cladocerans and copepodites were important in F, N and W. Piscivory was observed after notochord flexion and was important in terms of W. A positive correlation between mean prey size and both SL and lower jaw length (LJL was observed. The niche breadth (S did not vary with LJL, but the raw prey size range did. Larger copepodites, the absence of nauplii and the incorporation of fish larvae and a larger number of cladocerans in the diet accounted for the increase in mean prey size through increased larval size.

  11. Standardization of a geo-referenced fishing data set for the Indian Ocean bigeye tuna, Thunnus obesus (1952-2014)

    Science.gov (United States)

    Wibawa, Teja A.; Lehodey, Patrick; Senina, Inna

    2017-02-01

    Geo-referenced catch and fishing effort data of the bigeye tuna fisheries in the Indian Ocean over 1952-2014 were analyzed and standardized to facilitate population dynamics modeling studies. During this 62-year historical period of exploitation, many changes occurred both in the fishing techniques and the monitoring of activity. This study includes a series of processing steps used for standardization of spatial resolution, conversion and standardization of catch and effort units, raising of geo-referenced catch into nominal catch level, screening and correction of outliers, and detection of major catchability changes over long time series of fishing data, i.e., the Japanese longline fleet operating in the tropical Indian Ocean. A total of 30 fisheries were finally determined from longline, purse seine and other-gears data sets, from which 10 longline and 4 purse seine fisheries represented 96 % of the whole historical geo-referenced catch. Nevertheless, one-third of total nominal catch is still not included due to a total lack of geo-referenced information and would need to be processed separately, accordingly to the requirements of the study. The geo-referenced records of catch, fishing effort and associated length frequency samples of all fisheries are available at PANGAEA.864154" target="_blank">doi:10.1594/PANGAEA.864154.

  12. Global trophic ecology of yellowfin, bigeye, and albacore tunas: Understanding predation on micronekton communities at ocean-basin scales

    Science.gov (United States)

    Duffy, Leanne M.; Kuhnert, Petra M.; Pethybridge, Heidi R.; Young, Jock W.; Olson, Robert J.; Logan, John M.; Goñi, Nicolas; Romanov, Evgeny; Allain, Valerie; Staudinger, Michelle D.; Abecassis, Melanie; Choy, C. Anela; Hobday, Alistair J.; Simier, Monique; Galván-Magaña, Felipe; Potier, Michel; Ménard, Frederic

    2017-06-01

    Predator-prey interactions for three commercially valuable tuna species: yellowfin (Thunnus albacares), bigeye (T. obesus), and albacore (T. alalunga), collected over a 40-year period from the Pacific, Indian, and Atlantic Oceans, were used to quantitatively assess broad, macro-scale trophic patterns in pelagic ecosystems. Analysis of over 14,000 tuna stomachs, using a modified classification tree approach, revealed for the first time the global expanse of pelagic predatory fish diet and global patterns of micronekton diversity. Ommastrephid squids were consistently one of the top prey groups by weight across all tuna species and in most ocean bodies. Interspecific differences in prey were apparent, with epipelagic scombrid and mesopelagic paralepidid fishes globally important for yellowfin and bigeye tunas, respectively, while vertically-migrating euphausiid crustaceans were important for albacore tuna in the Atlantic and Pacific Oceans. Diet diversity showed global and regional patterns among tuna species. In the central and western Pacific Ocean, characterized by low productivity, a high diversity of micronekton prey was detected while low prey diversity was evident in highly productive coastal waters where upwelling occurs. Spatial patterns of diet diversity were most variable in yellowfin and bigeye tunas while a latitudinal diversity gradient was observed with lower diversity in temperate regions for albacore tuna. Sea-surface temperature was a reasonable predictor of the diets of yellowfin and bigeye tunas, whereas chlorophyll-a was the best environmental predictor of albacore diet. These results suggest that the ongoing expansion of warmer, less productive waters in the world's oceans may alter foraging opportunities for tunas due to regional changes in prey abundances and compositions.

  13. Screening of biodiesel production from waste tuna oil (Thunnus sp.), seaweed Kappaphycus alvarezii and Gracilaria sp.

    Science.gov (United States)

    Alamsjah, Mochammad Amin; Abdillah, Annur Ahadi; Mustikawati, Hutami; Atari, Suci Dwi Purnawa

    2017-09-01

    Biodiesel has several advantages over solar. Compared to solar, biodiesel has more eco-friendly characteristic and produces lower greenhouse gas emissions. Biodiesel that is made from animal fats can be produced from fish oil, while other alternative sources from vegetable oils are seaweed Kappaphycus alvarezii and Gracilaria sp. Waste tuna oil (Thunnus sp.) in Indonesia is commonly a side product of tuna canning industries known as tuna precook oil; on the other hand, seaweed Gracilaria sp. and Kappaphycus alvarezii are commonly found in Indonesia's seas. Seaweed waste that was used in the present study was 100 kg and in wet condition, and the waste oil was 10 liter. The seaweed was extracted with soxhletation method that used n-hexane as the solvent. To produce biodiesel, trans esterification was performed on the seaweed oil that was obtained from the soxhletation process and waste tuna oil. Biodiesel manufactured from seaweed K. alvarezii obtained the best score in flash point, freezing point, and viscosity test. However, according to level of manufacturing efficiency, biodiesel from waste tuna oil is more efficient and relatively easier compared to biodiesel from waste K. alvarezii and Gracilaria sp.

  14. Quantifying mercury isotope dynamics in captive Pacific bluefin tuna (Thunnus orientalis

    Directory of Open Access Journals (Sweden)

    Sae Yun Kwon

    2016-02-01

    Full Text Available Abstract Analyses of mercury (Hg isotope ratios in fish tissues are used increasingly to infer sources and biogeochemical processes of Hg in natural aquatic ecosystems. Controlled experiments that can couple internal Hg isotope behavior with traditional isotope tracers (δ13C, δ15N can improve the applicability of Hg isotopes as natural ecological tracers. In this study, we investigated changes in Hg isotope ratios (δ202Hg, Δ199Hg during bioaccumulation of natural diets in the pelagic Pacific bluefin tuna (Thunnus orientalis; PBFT. Juvenile PBFT were fed a mixture of natural prey and a dietary supplement (60% Loligo opalescens, 31% Sardinops sagax, 9% gel supplement in captivity for 2914 days, and white muscle tissues were analyzed for Hg isotope ratios and compared to time in captivity and internal turnover of δ13C and δ15N. PBFT muscle tissues equilibrated to Hg isotope ratios of the dietary mixture within ∼700 days, after which we observed a cessation in further shifts in Δ199Hg, and small but significant negative δ202Hg shifts from the dietary mixture. The internal behavior of Δ199Hg is consistent with previous fish studies, which showed an absence of Δ199Hg fractionation during Hg bioaccumulation. The negative δ202Hg shifts can be attributed to either preferential excretion of Hg with higher δ202Hg values or individual variability in captive PBFT feeding preferences and/or consumption rates. The overall internal behavior of Hg isotopes is similar to that described for δ13C and δ15N, though observed Hg turnover was slower compared to carbon and nitrogen. This improved understanding of internal dynamics of Hg isotopes in relation to δ13C and δ15N enhances the applicability of Hg isotope ratios in fish tissues for tracing Hg sources in natural ecosystems.

  15. Mercury accumulation in Yellowfin tuna (Thunnus albacares) with regards to muscle type, muscle position and fish size.

    Science.gov (United States)

    Bosch, Adina C; O'Neill, Bernadette; Sigge, Gunnar O; Kerwath, Sven E; Hoffman, Louwrens C

    2016-01-01

    The concentrations and relationships between individual mercury species and total mercury were investigated in different muscle parts and sizes of Yellowfin tuna (Thunnus albacares). Fourteen Yellowfin tuna caught in the South Atlantic off the coast of South Africa had an average total Hg (tHg) concentration of 0.77 mg/kg wet weight. No differences were detected (p > 0.05) in tHg, MethylHg (MeHg) or inorganic Hg (iHg) accumulation among the four white muscle portions across the carcass, but both tHg and iHg were found in higher concentrations (p < 0.001) in dark muscle than white muscle. Positive linear correlations with fish weight were found for both tHg (r = 0.79, p < 0.001) and MeHg (r = 0.75, p < 0.001) concentrations. A prediction model was formulated to calculate toxic MeHg concentrations from measured tHg concentrations and fish weight (cMeHg = 0.073 + 1.365 · tHg-0.008 · w). As sampling sites and subsampling methods could affect toxicity measurements, we provide recommendations for sampling guidelines. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Entrenamiento: “Cambios ontogénicos a la tolerancia de estresores a bajas y altas temperaturas en larvas y juveniles de PBT (Thunnus orientalis).” Nara, Japón 2015

    OpenAIRE

    Villarreal, Yazmin

    2015-01-01

    Dentro de las actividades a desarrollar bajo el marco del Proyecto “Estudio comparativo de la biología reproductiva y del ciclo vital temprano del atún aleta amarilla y el atún aleta azul para el manejo de estos recursos”, se estableció un plan de trabajo, donde incluía el entrenamiento técnico-científico del personal de la Autoridad de los Recursos Acuáticos de Panamá (ARAP). Se acordó las visitas para realizar ensayos con esta especie en las Estaciones de cultivo de atún aleta azul (Thunnus...

  17. Factores de discriminación y tasas de renovación isotópica de nitrógeno en larvas de atún rojo de cultivo (Thunnus thynnus): efectos de la transferencia materna

    OpenAIRE

    Uriarte, Amaya; García, Alberto; Ortega, Aurelio; de la Gándara, Fernando; Quintanilla, José; Laiz-Carrión, Raúl

    2016-01-01

    El análisis de isótopos estables para estudiar la dieta de los animales requiere estimaciones de las tasas de rotación isotópicas (tiempo medio, t50) y factores de discriminación (Δ) para una correcta interpretación de los patrones tróficos. Los isótopos estables de carbono y nitrógeno se analizaron en los huevos y larvas criadas de Thunnus thynnus, así como para las diferentes dietas suministradas durante el experimento. Los resultados mostraron altos valores de δ15N en huevos y larvas (n=64...

  18. Evaluation of the proximate quality of the combination of Tuna (Thunnus albacares) and white oyster mushroom (Pleurotus ostreatus) nuggets

    Science.gov (United States)

    Yufidasari, H. S.; Prihanto, A. A.; Nurdiani, R.; Jaziri, A. A.

    2018-04-01

    Nugget is a processed meat product which has great market demand but need variations to increase its nutritional content. Tuna is rich in omega-3 protein, vitamins, and minerals. White oyster mushrooms have high nutritional content which are about 23-33% protein, 36-68 % carbohydrates and 12-22 % amino acids. The purpose of this research is to evaluate the chemical quality of Tuna nugget (Thunnus albacores) with combination of white oyster mushroom (Pleurotus ostreatus). Complete Randomized Design (RAL) with parameters of Tuna and white oyster mushroom formulation, TJ1 (70 % Tuna: 30 % white oyster mushroom), TJ2 (50 % Tuna: 50 % white oyster mushroom), TJ3 (30 % Tuna: 70 % white oyster mushroom), and Control or K Treatment (100 % Tuna) is used. Results of Tuna nuggets with white oyster mushroom combination showed the highest value of water content in TJ3 50.14 %, protein K 19.6 %, fat TJ3 22.98 %, ash K 3.99 % and 2.47 % crude fiber. From these results, there is a need for further research on fat, ash and coarse fiber content that is used in the manufacture of fish nuggets combined with oyster mushrooms because it failed to meet Indonesian National Standard (SNI).

  19. Dietary evidence of mesopelagic and pelagic foraging by Atlantic bluefin tuna (Thunnus thynnus L.) during autumn migrations to the Iceland Basin

    DEFF Research Database (Denmark)

    Olafsdottir, Droplaug; MacKenzie, Brian; Chosson-P, Valérie

    2016-01-01

    Atlantic bluefin tuna (ABFT; Thunnus thynnus) is a large highly mobile predator fish species in the North Atlantic Ocean and Mediterranean Sea. Knowledge of its trophic role in marine food webs in summer feeding areas is presently based on recent (1980–2010s) sampling in the Bay of Biscay, Gulfs...... of Maine and St. Lawrence, and from historical (1950–1960s) sampling in the Norwegian-North Sea-Kattegat. No study has yet investigated the diets of ABFT in Icelandic waters, where it supported an experimental fishery during 1996–2005, nor in any region north of the Bay of Biscay since the 1960s. However......, north Atlantic temperatures and fish species distributions, including some ABFT prey species (e.g., mackerel) have been changing in the 2000s. New knowledge of ABFT diets in previously understudied parts of the species range will be useful for understanding factors affecting the trophic role, migration...

  20. Abundance and Distribution Patterns of Thunnus albacares in Isla del Coco National Park through Predictive Habitat Suitability Models.

    Directory of Open Access Journals (Sweden)

    Cristina Gonzáles-Andrés

    Full Text Available Information on the distribution and habitat preferences of ecologically and commercially important species is essential for their management and protection. This is especially important as climate change, pollution, and overfishing change the structure and functioning of pelagic ecosystems. In this study, we used Bayesian hierarchical spatial-temporal models to map the Essential Fish Habitats of the Yellowfin tuna (Thunnus albacares in the waters around Isla del Coco National Park, Pacific Costa Rica, based on independent underwater observations from 1993 to 2013. We assessed if observed changes in the distribution and abundance of this species are related with habitat characteristics, fishing intensity or more extreme climatic events, including the El Niño Southern Oscillation, and changes on the average sea surface temperature. Yellowfin tuna showed a decreasing abundance trend in the sampled period, whereas higher abundances were found in shallow and warmer waters, with high concentration of chlorophyll-a, and in surrounding seamounts. In addition, El Niño Southern Oscillation events did not seem to affect Yellowfin tuna distribution and abundance. Understanding the habitat preferences of this species, using approaches as the one developed here, may help design integrated programs for more efficient management of vulnerable species.

  1. Otolith chemistry discriminates natal signatures of yellowfin tuna (Thunnus albacares) in the Atlantic Ocean

    Science.gov (United States)

    Kitchens, L. L.; Rooker, J. R.

    2016-02-01

    In this study, the otolith chemistry of young-of-the-year (YOY) yellowfin tuna (Thunnus albacares) was examined to determine whether chemical signatures are distinct across different putative spawning areas in the Atlantic Ocean. Yellowfin tuna is a highly migratory species that is currently managed as a single panmictic stock in the Atlantic Ocean; however, uncertainty remains regarding the population structure of yellowfin in this region, particularly concerning the degree of mixing between spawning populations. Analysis of naturally occurring chemical tracers in otoliths provides a valuable means to reconstruct a fish's environmental history and is thus a promising approach for delineating stock structure of Atlantic yellowfin tuna. YOY yellowfin tuna otoliths were collected from 5 locations in the Atlantic Ocean (Gulf of Mexico, SE Caribbean, Brazil, Cape Verde, and Gulf of Guinea) from 2013-2015 and trace element (Li, Mg, Mn, Co, Cu, Sr, Zn, and Ba) and stable isotope (δ13C and δ18O) analyses were conducted to investigate regional variation in otolith chemical composition. Results show significant differences among nursery areas in both trace element (MANOVA, p<0.001) and δ13C and δ18O signatures (ANOVA, p=0.017 and p=0.001, respectively). Particularly high spatial separation was observed based on eastern Atlantic (Gulf of Guinea + Cape Verde) and western Atlantic (Gulf of Mexico + Brazil + Martinique) nursery areas, indicating the approach has promise for distinguishing migrants displaying trans-ocean movement. These chemical signatures will be used to assign adult yellowfin tuna to their nursery of origin, ultimately providing an improved understanding of the stock structure and movement of yellowfin tuna in the Atlantic Ocean.

  2. Distinct Yellowfin Tuna (Thunnus albacares Stocks Detected in Western and Central Pacific Ocean (WCPO Using DNA Microsatellites.

    Directory of Open Access Journals (Sweden)

    Roselyn D Aguila

    Full Text Available The yellowfin tuna, Thunnus albacares (Bonnaterre, 1788, covers majority of the Philippines' tuna catch, one of the major fisheries commodities in the country. Due to its high economic importance sustainable management of these tunas has become an imperative measure to prevent stock depletion. Currently, the Philippine yellowfin tuna is believed to be part of a single stock of the greater WCPO though some reports suggest otherwise. This study therefore aims to establish the genetic stock structure of the said species in the Philippines as compared to Bismarck Sea, Papua New Guinea using nine (9 DNA microsatellite markers. DNA microsatellite data revealed significant genetic differentiation between the Philippine and Bismarck Sea, Papua New Guinea yellowfin tuna samples. (FST = 0.034, P = 0.016, which is further supported by multilocus distance matrix testing (PCoA and model-based clustering (STRUCTURE 2.2.With these findings, this study posits that the yellowfin tuna population in the Philippines is a separate stock from the Bismarck Sea population. These findings add evidence to the alternative hypothesis of having at least 2 subpopulations of yellowfin tuna in the WCPO and calls for additional scientific studies using other parameters to investigate this. Accurate population information is necessary in formulating a more appropriate management strategy for the sustainability of the yellowfin tuna not only in the Philippines but also in the WCPO.

  3. A continuous time delay-difference type model (CTDDM) applied to stock assessment of the southern Atlantic albacore Thunnus alalunga

    Institute of Scientific and Technical Information of China (English)

    LIAO Baochao; LIU Qun; ZHANG Kui; Abdul BASET; Aamir Mahmood MEMON; Khadim Hussain MEMON; HAN Yanan

    2016-01-01

    A continuous time delay-difference model (CTDDM) has been established that considers continuous time delays of biological processes.The southern Atlantic albacore (Thunnus alalunga) stock is the one of the commercially important tuna population in the marine world.The age structured production model (ASPM) and the surplus production model (SPM) have already been used to assess the albacore stock.However,the ASPM requires detailed biological information and the SPM lacks the biological realism.In this study,we focus on applying a CTDDM to the southern Atlantic albacore (T.alalunga) species,which provides an alternative method to assess this fishery.It is the first time that CTDDM has been provided for assessing the Atlantic albacore (T.alalunga) fishery.CTDDM obtained the 80% confidence interval of MSY (maximum sustainable yield) of(21510 t,23118 t).The catch in 2011 (24100 t) is higher than the MSY values and the relative fishing mortality ratio (F2011/FMSY) is higher than 1.0.The results of CTDDM were analyzed to verify the proposed methodology and provide reference information for the sustainable management of the southern Atlantic albacore stock.The CTDDM treats the recruitment,the growth,and the mortality rates as all varying continuously over time and fills gaps between ASPM and SPM in this stock assessment.

  4. Spawning Dynamics and Size Related Trends in Reproductive Parameters of Southern Bluefin Tuna, Thunnus maccoyii.

    Directory of Open Access Journals (Sweden)

    Jessica H Farley

    Full Text Available Knowledge of spawning behaviour and fecundity of fish is important for estimating the reproductive potential of a stock and for constructing appropriate statistical models for assessing sustainable catch levels. Estimates of length-based reproductive parameters are particularly important for determining potential annual fecundity as a function of fish size, but they are often difficult to estimate reliably. Here we provide new information on the reproductive dynamics of southern bluefin tuna (SBT Thunnus maccoyii through the analysis of fish size and ovary histology collected on the spawning ground in 1993-1995 and 1999-2002. These are used to refine previous parameter estimates of spawning dynamics and investigate size related trends in these parameters. Our results suggest that the small SBT tend to arrive on the spawning ground slightly later and depart earlier in the spawning season relative to large fish. All females were mature and the majority were classed as spawning capable (actively spawning or non-spawning with a very small proportion classed as regressing. The fraction of females spawning per day decreased with fish size, but once females start a spawning episode, they spawned daily irrespective of size. Mean batch fecundity was estimated directly at 6.5 million oocytes. Analysis of ovary histology and ovary weight data indicated that relative batch fecundity, and the duration of spawning and non-spawning episodes, increased with fish size. These reproductive parameter estimates could be used with estimates of residency time on the spawning ground as a function of fish size (if known and demographic data for the spawning population to provide a time series of relative annual fecundity for SBT.

  5. Amino Acid Isotope Incorporation and Enrichment Factors in Pacific Bluefin Tuna, Thunnus orientalis

    Science.gov (United States)

    Bradley, Christina J.; Madigan, Daniel J.; Block, Barbara A.; Popp, Brian N.

    2014-01-01

    Compound specific isotopic analysis (CSIA) of amino acids has received increasing attention in ecological studies in recent years due to its ability to evaluate trophic positions and elucidate baseline nutrient sources. However, the incorporation rates of individual amino acids into protein and specific trophic discrimination factors (TDFs) are largely unknown, limiting the application of CSIA to trophic studies. We determined nitrogen turnover rates of individual amino acids from a long-term (up to 1054 days) laboratory experiment using captive Pacific bluefin tuna, Thunnus orientalis (PBFT), a large endothermic pelagic fish fed a controlled diet. Small PBFT (white muscle δ15N∼11.5‰) were collected in San Diego, CA and transported to the Tuna Research and Conservation Center (TRCC) where they were fed a controlled diet with high δ15N values relative to PBFT white muscle (diet δ15N∼13.9‰). Half-lives of trophic and source amino acids ranged from 28.6 to 305.4 days and 67.5 to 136.2 days, respectively. The TDF for the weighted mean values of amino acids was 3.0 ‰, ranging from 2.2 to 15.8 ‰ for individual combinations of 6 trophic and 5 source amino acids. Changes in the δ15N values of amino acids across trophic levels are the underlying drivers of the trophic 15N enrichment. Nearly all amino acid δ15N values in this experiment changed exponentially and could be described by a single compartment model. Significant differences in the rate of 15N incorporation were found for source and trophic amino acids both within and between these groups. Varying half-lives of individual amino acids can be applied to migratory organisms as isotopic clocks, determining the length of time an individual has spent in a new environment. These results greatly enhance the ability to interpret compound specific isotope analyses in trophic studies. PMID:24465724

  6. Isotopic discrimination factors and nitrogen turnover rates in reared Atlantic bluefin tuna larvae (Thunnus thynnus: effects of maternal transmission

    Directory of Open Access Journals (Sweden)

    Amaya Uriarte

    2016-11-01

    Full Text Available The use of stable isotope analysis to study animal diets requires estimates of isotopic turnover rates (half time, t50 and discrimination factors (Δ for an accurate interpretation of trophic patterns. The stable isotopes of carbon and nitrogen were analysed for eggs and reared larvae of Thunnus thynnus, as well as for the different diets supplied during the experiment. The results showed high values of δ15N in eggs and larvae (n=646 until 4 DAH. After this time lapse, the stable isotope values declined progressively until 12 DAH, when notochord flexion began. The δ13C showed an inverse trend, suggesting that maternal inheritance of the stable isotopes is evident until pre-flexion stages. This study proposes a model for estimating maternal isotopic signatures of bluefin broodstock. After notochord flexion, larvae were fed with aquaculture-bred gilthead seabream, which resulted in a rapid increase of bluefin larvae δ15N values together with a rapid decrease in δ13C values. The estimated nitrogen half-time to reach the steady state from the diet was 2.5±0.3 days and the discrimination factor was 0.4±0.3(‰. These results represent the first data set that has allowed isotopic nitrogen turnover rates and discrimination factors of the larval stages of bluefin tuna to be estimated.

  7. Response of plasma and urinary uric acid, creatine and creatinine to dietary protein deficiency and/or whole body gamma-irradiation in desert rodent and albino rats

    Energy Technology Data Exchange (ETDEWEB)

    Roushdy, H M; El-Husseini, M; Saleh, F [National Centre for Radiation Research and Technology, Cairo (Egypt)

    1985-01-01

    The effect of whole body gamma-irradiation on the levels of plasma and urinary uric acid, creatine and creatinine was studied in the desert rodent, Psammomys obesus and albino rats subjected to dietary protein deficiency. In albino rats, the levels of uric acid in plasma and urine were higher in the animals kept on high protein diets than in those maintained on non-protein ones. Radiation exposure caused a significant increase in uric acid concentration both in plasma and urine of albino rats, whereas in Psammomys obesus obesus, it exerted a significant drop in uric acid concentration in blood paralleling a marked rise in the daily uric acid excretion in the urine, especially with the high radiation level of 1170 r. Creatinine concentrations in plasma and urine of albino rats were higher than the corresponding values in Psammomys obesus obesus. Radiation exposure in general caused an increase in the creatinine concentration in blood and a decrease in its concentration in urine. Plasma creatine was shown to increase due to the effect of radiation exposure. This runs in parallel with the increase in the excretion of creatine in urine. Creatinuria observed in whole body irradiation is obviously caused by a defect in the ability of skeletal muscle to take up creatine from blood. Such abnormality could be the result of direct damage to the muscle caused by incident radiation.

  8. Response of plasma and urinary uric acid, creatine and creatinine to dietary protein deficiency and/or whole body gamma-irradiation in desert rodent and albino rats

    International Nuclear Information System (INIS)

    Roushdy, H.M.; El-Husseini, M.; Saleh, F.

    1985-01-01

    The effect of whole body gamma-irradiation on the levels of plasma and urinary uric acid, creatine and creatinine was studied in the desert rodent, Psammomys obesus and albino rats subjected to dietary protein deficiency. In albino rats, the levels of uric acid in plasma and urine were higher in the animals kept on high protein diets than in those maintained on non-protein ones. Radiation exposure caused a significant increase in uric acid concentration both in plasma and urine of albino rats, whereas in Psammomys obesus obesus, it exerted a significant drop in uric acid concentration in blood paralleling a marked rise in the daily uric acid excretion in the urine, especially with the high radiation level of 1170 r. Creatinine concentrations in plasma and urine of albino rats were higher than the corresponding values in Psammomys obesus obesus. Radiation exposure in general caused an increase in the creatinine concentration in blood and a decrease in its concentration in urine. Plasma creatine was shown to increase due to the effect of radiation exposure. This runs in parallel with the increase in the excretion of creatine in urine. Creatinuria observed in whole body irradiation is obviously caused by a defect in the ability of skeletal muscle to take up creatine from blood. Such abnormality could be the result of direct damage to the muscle caused by incident radiation

  9. Physicochemical evaluation of the effects of irradiation and evisceration on the conservation of refrigerated blackfin tuna (Thunnus atlanticus)

    Energy Technology Data Exchange (ETDEWEB)

    Monteiro, Maria L.G.; Marsico, Eliane T. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Faculdade de Veterinaria. Dept. de Tecnologia de Alimentos], e-mail: marialuciaguerra@yahoo.com.br, e-mail: elianee@vm.uff.br; Vital, Helio C. [Centro Tecnologico do Exercito (CTEx), Rio de Janeiro, RJ (Brazil). Secao de Defesa Nuclear], e-mail: vital@ctex.eb.br

    2009-07-01

    Tuna is among the most traded fishes in Brazil, however efficiently delaying its fast deterioration is still a major practical challenge. Irradiation has been proposed as a safe and powerful alternative tool for conservation of seafood. This work investigated the effects of irradiation on the physicochemical quality of refrigerated blackfin tuna (Thunnus atlanticus). Analyses of pH, total volatile bases (TVB-N), ammonia and biogenic amines (histamine, cadaverine and putrescine) were performed in order to determine the degree of conservation. The samples were subjected to four different treatments aiming at evaluating the efficiency of irradiation, evisceration and both combined. The figures measured for those parameters, all of them related to the degree of conservation, were found to increase with time regardless of the treatment. In addition, data for irradiated samples remained consistently lower than for unirradiated ones, indicating a better level of preservation that led to an extended shelf life of 14 days. In contrast, excessive levels of those indicators of degradation were found in unirradiated samples after 7 to 10 days of storage. In addition, some evidence was found that evisceration slightly increased quality, consequently promoting a small extension in shelf life of unirradiated samples. Finally, it can be concluded with basis on the results of the physicochemical parameters studied that treatment of fresh refrigerated blackfin tuna by irradiation with 2.5 kGy efficiently preserved freshness and extended the shelf life of the product from 7 to 14 days. (author)

  10. Physicochemical evaluation of the effects of irradiation and evisceration on the conservation of refrigerated blackfin tuna (Thunnus atlanticus)

    International Nuclear Information System (INIS)

    Monteiro, Maria L.G.; Marsico, Eliane T.; Vital, Helio C.

    2009-01-01

    Tuna is among the most traded fishes in Brazil, however efficiently delaying its fast deterioration is still a major practical challenge. Irradiation has been proposed as a safe and powerful alternative tool for conservation of seafood. This work investigated the effects of irradiation on the physicochemical quality of refrigerated blackfin tuna (Thunnus atlanticus). Analyses of pH, total volatile bases (TVB-N), ammonia and biogenic amines (histamine, cadaverine and putrescine) were performed in order to determine the degree of conservation. The samples were subjected to four different treatments aiming at evaluating the efficiency of irradiation, evisceration and both combined. The figures measured for those parameters, all of them related to the degree of conservation, were found to increase with time regardless of the treatment. In addition, data for irradiated samples remained consistently lower than for unirradiated ones, indicating a better level of preservation that led to an extended shelf life of 14 days. In contrast, excessive levels of those indicators of degradation were found in unirradiated samples after 7 to 10 days of storage. In addition, some evidence was found that evisceration slightly increased quality, consequently promoting a small extension in shelf life of unirradiated samples. Finally, it can be concluded with basis on the results of the physicochemical parameters studied that treatment of fresh refrigerated blackfin tuna by irradiation with 2.5 kGy efficiently preserved freshness and extended the shelf life of the product from 7 to 14 days. (author)

  11. Study on the change of total fat content and fatty acid composition of the ethanol extract from cooking drips of thunnus thynnus by ionizing irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hee Sub; Choi, Jong Il; Kim, Hyun Joo; Kim, Jin Kyu; Byun, Myung Woo; Lee, Ju Woon [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Yoo, Cheon Woo; Kim, Ju Bong [Dongwon Research and Development Center, Seongnam (Korea, Republic of); Hwang, Young Jung [Division of Food Science, Jinju International University, Jinju (Korea, Republic of); Chung, Young Jin [Dept. of Food and Nutrition, Chungnam National University, Daejeon (Korea, Republic of)

    2008-05-15

    This study was conducted to examine the effect of a gamma irradiation (GM) and an electron-beam irradiation (EB) on the total fat content and fatty acid composition of ethanol extract from cooking drips of Thunnus thynnus (ECT). The total fat content of samples were determined by fat extraction (Folch method) and fatty acid composition was by gas chromatography mass spectrometry (GC-MS) after fat extraction. The results showed that total fat contents were not changed by GM and EB up to the dose of 50 kGy. The content of unsaturated fatty acids (USFA) such as vaccenic acid and DHA, was decreased by irradiation. But, the content of palmitoleic acid was not changed by GM. In contrast, the content of saturated fatty acids(SFA) such as myristic acid and palmitic acid, was increased by the irradiation. But, the content of stearic acid was decreased with the increase of irradiation dose. Also, it has been shown that the GM had further affected the change of fatty acid content than EB.

  12. Study on the change of total fat content and fatty acid composition of the ethanol extract from cooking drips of thunnus thynnus by ionizing irradiation

    International Nuclear Information System (INIS)

    Lee, Hee Sub; Choi, Jong Il; Kim, Hyun Joo; Kim, Jin Kyu; Byun, Myung Woo; Lee, Ju Woon; Yoo, Cheon Woo; Kim, Ju Bong; Hwang, Young Jung; Chung, Young Jin

    2008-01-01

    This study was conducted to examine the effect of a gamma irradiation (GM) and an electron-beam irradiation (EB) on the total fat content and fatty acid composition of ethanol extract from cooking drips of Thunnus thynnus (ECT). The total fat content of samples were determined by fat extraction (Folch method) and fatty acid composition was by gas chromatography mass spectrometry (GC-MS) after fat extraction. The results showed that total fat contents were not changed by GM and EB up to the dose of 50 kGy. The content of unsaturated fatty acids (USFA) such as vaccenic acid and DHA, was decreased by irradiation. But, the content of palmitoleic acid was not changed by GM. In contrast, the content of saturated fatty acids(SFA) such as myristic acid and palmitic acid, was increased by the irradiation. But, the content of stearic acid was decreased with the increase of irradiation dose. Also, it has been shown that the GM had further affected the change of fatty acid content than EB

  13. Levels of dioxin (PCDD/F) and PCBs in a random sample of Australian aquaculture-produced Southern Bluefin Tuna (Thunnus maccoyii)

    Energy Technology Data Exchange (ETDEWEB)

    Padula, D.; Madigan, T.; Kiermeier, A.; Daughtry, B.; Pointon, A. [South Australian Research and Development Inst. (Australia)

    2004-09-15

    To date there has been no published information available on the levels of dioxin (PCDD/F) and PCBs in Australian aquaculture-produced Southern Bluefin Tuna (Thunnus maccoyii). Southern Bluefin Tuna are commercially farmed off the coast of Port Lincoln in the state of South Australia, Australia. This paper reports the levels of dioxin (PCDD/F) and PCBs in muscle tissue samples from 11 randomly sampled aquaculture-produced Southern Bluefin Tuna collected in 2003. Little published data exists on the levels of dioxin (PCDD/F) and PCBs in Australian aquacultureproduced seafood. Wild tuna are first caught in the Great Australian Bight in South Australian waters, and are then brought back to Port Lincoln where they are ranched in sea-cages before being harvested and exported to Japan. The aim of the study was to identify pathways whereby contaminants such as dioxin (PCDD/F) and PCBs may enter the aquaculture production system. This involved undertaking a through chain analysis of the levels of dioxin (PCDD/F) and PCBs in wild caught tuna, seafloor sediment samples from the marine environment, levels in feeds and final harvested exported product. Detailed study was also undertaken on the variation of dioxin (PCDD/F) and PCBs across individual tuna carcases. This paper addresses the levels found in final harvested product. Details on levels found in other studies will be published elsewhere shortly.

  14. Abundancia, tamaño y estructura poblacional del tiburón punta blanca de arrecife, Triaenodon obesus (Carcharhiniformes: Carcharhinidae, en Bahía Chatham, Parque Nacional Isla del Coco, Costa Rica Abundance, size and population structure of whitetip reef sharks, Triaenodon obesus (Carcharhiniformes: Carcharhinidae, in Bahía Chatham, Parque Nacional Isla del Coco, Costa Rica

    Directory of Open Access Journals (Sweden)

    Ilena Zanella

    2012-11-01

    Full Text Available Doce especies de tiburones habitan las aguas del Parque Nacional Isla del Coco (PNIC y uno de los más abundantes es el tiburón punta blanca de arrecife, Triaenodon obesus. El presente estudio determinó la abundancia, tallas y estructura de la población de esta especie en la zona de Bahía Chatham, PNIC. Se utilizó el método de marcaje y recaptura y se realizaron conteos subacuáticos visuales, con el fin de determinar su abundancia relativa y contabilizar recapturas visuales. Los tiburones punta blanca de Bahía Chatham no presentan segregación ontogénica espacial definida; pero si una alta fidelidad a los a sitios de residencia dentro de esta bahía. La longitud total promedio de los tiburones marcados fue de 101.8±12.1cm, con una longitud total máxima de 130.0cm y una mínima de 71.0cm. La mediana de las longitudes totales de los tiburones machos (103.5±21.33cm y hembras (100.1±11.2cm no difirieron significativamente (H = 1.78; p=0.1818. La abundancia relativa en Bahía Chatham, PNIC fue de 49.5±10.4 tiburones/h. El tamaño estimado de la población usando el método de de captura-recaptura fue de 408 (IC=181-1050.Approximately 12 species of shark inhabit at Coco Island National Park (PNIC; some are migratory, such as the hammerhead shark (Sphyrna lewini and whale shark (Rincodon typus, and others are resident, like the whitetip shark (Triaenodon obesus. The whitetip shark is a species related to coral reefs, it inhabits coastal environments and is nocturnal and, it is very common in tropical waters, but there are few studies worldwide. In fact, only short researches have been done about their behavior at PNIC. Therefore, this study aimed to give data about the abundance, size and population structure of the whitetip shark at Chatham Bay in Coco Island National Park, providing baseline information for monitoring its population which is also very vulnerable to climate change. In order to accomplish this aim, a mark-recapture method

  15. Brain morphology and immunohistochemical localization of the gonadotropin-releasing hormone in the bluefin tuna, Thunnus thynnus

    Directory of Open Access Journals (Sweden)

    G Palmieri

    2009-08-01

    Full Text Available The present study was focused on the morphology of the diencephalic nuclei (likely involved in reproductive functions as well as on the distribution of GnRH (gonadotropin-releasing hormone in the rhinencephalon, telencephalon and the diencephalon of the brain of bluefin tuna (Thunnus thynnus by means of immunohistochemistry. Bluefin tuna has an encephalization quotient (QE similar to that of other large pelagic fish. Its brain exhibits well-developed optic tecta and corpus cerebelli. The diencephalic neuron cell bodies involved in reproductive functions are grouped in two main nuclei: the nucleus preopticus-periventricularis and the nucleus lateralis tuberis. The nucleus preopticus-periventricularis consists of the nucleus periventricularis and the nucleus preopticus consisting of a few sparse multipolar neurons in the rostral part and numerous cells closely packed and arranged in several layers in its aboral part. The nucleus lateralis tuberis is located in the ventral-lateral area of the diencephalon and is made up of a number of large multipolar neurones. Four different polyclonal primary antibodies against salmon (sGnRH, chicken (cGnRH-II (cGnRH-II 675, cGnRH-II 6 and sea bream (sbGnRH were employed in the immunohistochemical experiments. No immunoreactive structures were found with anti sbGnRH serum. sGnRH and cGnRH-II antisera revealed immunoreactivity in the perikarya of the olfactory bulbs, preopticus-periventricular nucleus, oculomotor nucleus and midbrain tegmentum. The nucleus lateralis tuberis showed immunostaining only with anti-sGnRH serum. Nerve fibres immunoreactive to cGnRH and sGnRH sera were found in the olfactory bulbs, olfactory nerve and neurohypophysis. The significance of the distribution of the GnRHimmunoreactive neuronal structures is discussed.

  16. Identification of parvalbumin and two new thermolabile major allergens of Thunnus tonggol using a proteomics approach.

    Science.gov (United States)

    Rosmilah, Misnan; Shahnaz, Murad; Meinir, Jones; Masita, Arip; Noormalin, Abdullah; Jamaluddin, Mohamed

    2013-01-01

    The longtail tuna (Thunnus tonggol) is widely consumed in Asia. Parvalbumin, the main major allergen of fish, has been well identified in multiple fish species, yet little is known about the allergenic proteins in T. tonggol. Thus, the aim of this study was to characterize the major allergens of T. tonggol using a proteomics approach. Raw and boiled extracts of the fish were prepared. Fish proteins were separated by means of SDS-PAGE and two-dimensional (2-DE) electrophoresis. 1-DE immunoblotting of raw extract was performed with sera from fish-allergic patients. Ten sera were further analysed by 2-DE immunoblotting. Selected major allergenic protein spots were excised, trypsin digested and analysed by means of mass spectrometry. SDS-PAGE of raw extract revealed 26 protein fractions, while boiled extract demonstrated fewer bands. The 2-DE gel profile of the raw extract further fractionated the protein bands to more than 100 distinct protein spots. 1-DE immunoblotting of raw extract exhibited two thermolabile protein fractions of 42 and 51 kDa as the major allergens, while the boiled extract only revealed a single IgE-binding band at 151 kDa. 2-DE immunoblotting of raw extract further detected numerous major IgE-reactive spots of 11-13, 42 and 51 kDa. Mass spectrometry analysis of the peptides generated from the 12, 42 and 51 kDa digested spots indicated that these spots were parvalbumin, creatine kinase and enolase, respectively. In addition to parvalbumin, two new thermolabile allergens were identified as major allergenic proteins of T. tonggol. This study proved that both thermostable and thermolabile proteins are important in local tuna allergy and should be included in diagnostic strategies.

  17. Anti-termite efficacy of Capparis decidua and its combinatorial ...

    African Journals Online (AJOL)

    Michael Horsfall

    ABSTRACT: Capparis deciduas and its combinatorial mixtures were evaluated to observe the anti-termite efficacy against Indian white termite Odontotermes obesus. These have shown very high termiticidal activity and wood protection in the soil. It is proved by very low LD50 values i.e. 0.0218mg/g and 0.021mg/g obtained ...

  18. Histamine development and bacterial diversity in microbially-challenged tonggol (Thunnus tonggol) under temperature abuse during canning manufacture.

    Science.gov (United States)

    Hongpattarakere, Tipparat; Buntin, Nirunya; Nuylert, Aem

    2016-01-01

    Histamine formation and bacteriological changes caused by temperature abuse commonly occurring in the manufacturing process of standard canned tuna was assessed in microbiologically challenged tonggol (Thunnus tonggol). The in situ challenge was performed by water-soaking at 26-28 °C for 7 h to ensure the multiplication and active phase of fish microflora. Right after pre-cooking to back-bone temperature (BBT) of 50-52 °C, histamine dropped to 5.17 ± 2.71 ppm, and slowly reached 6.84 ± 1.69 ppm at 16 h abuse. On the contrary, histamine was reduced to 2.87 ± 1.23 ppm and eventually reached 5.01 ± 1.32 ppm at 24 h abuse in the pre-cooked fish previously frozen. The numbers of total aerobic bacteria, Enterobactericeae, psychrotroph, histamine forming bacteria (HFB) and diversity of fish microflora were revealed by cultural and nested PCR-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) techniques. Interestingly, frozen storage effectively halted histamine formation in raw fish throughout 16 h abuse despite the presence of HFB. These included the prolific strains of Morganella morganii, Proteus penneri, Proteus mirabilin, Citrobacter spp. The nested PCR-DGGE profile confirmed the presence of M. morganii and Citrobacter spp. in raw fish. These prolific strains were hardly observed in the precooked fish previously frozen. Frozen storage did not only promote even histamine distribution throughout fish muscle but also enhanced histamine loss during thawing and pre-cooking. Therefore, pre-cooking and frozen storage were proven to be the effective combined hurdles not only to reduce but also prolong histamine formation of the challenged toggol throughout 24 h of temperature abuse during canning process.

  19. Effect of tuna skin gelatin-based coating enriched with seaweed extracts on the quality of tuna fillets during storage at 4 °C

    Directory of Open Access Journals (Sweden)

    Milene Vala

    2017-10-01

    Full Text Available Nowadays, consumers demand high quality food products with an extended shelf-life without chemical additives. Edible coatings (EC containing natural compounds are a promising preservation technology for raw seafood without compromising fresh-like appeal and nutritional content.The aim of this work was to evaluate the effect of Thunnus obesus skin gelatin-based EC containing Codium spp. or Fucus vesiculosus extracts on raw tuna preservation. Three gelatin-based EC (gelatin (5 % + glycerol (25 %; gelatin (5 % + Codium spp. (1 % + glycerol (25 %; gelatin (5 % + Fucus vesiculosus (1 % + glycerol (25 % were applied directly on the surface of tuna fillets. Functional properties of gelatin and gelatin-based EC containing seaweed extracts were also studied. The gelatin was extracted by an acid-swelling process in the presence/absence of pepsin, followed by subsequent heating/refrigeration, after a pre-treatment with NaOH. The type of acid, temperature and concentration of NaOH greatly influence the process yield. The higher extraction yield was achieved using acetic acid in the presence of pepsin by subsequent refrigeration, especially when skins were previously treated with NaOH (0.2 M. Tuna quality was assessed over 12 days of storage at 4 ± 1 °C in terms of chemical and microbial indices. Results showed that tuna skin gelatin-based EC avoids tuna deterioration. Microbial growth, assessed by total viable counts, and total volatile basic nitrogen were maintained below the maximum limits recommended, contrarily to the control. Additionally, the use of EC increased the stability of red colour during storage. 

  20. Electric Double Layer at Metal Oxide Surfaces: Static Properties of the Cassiterite-Water Interface

    Czech Academy of Sciences Publication Activity Database

    Vlček, Lukáš; Zhang, Z.; Machesky, M.L.; Fenter, P.; Rosenqvist, J.; Wesolowski, D.J.; Anovitz, L. M.; Předota, Milan; Cummings, P.T.

    2007-01-01

    Roč. 23, č. 9 (2007), s. 4925-4937 ISSN 0743-7463 Grant - others:OBES(US) DE-AC05-00OR22727; OBES(US) DE-AC02-05CH11231; OBES(US) DE-AC02-06CH11357 Institutional research plan: CEZ:AV0Z40720504 Source of funding: N - neverejné zdroje ; N - neverejné zdroje ; N - neverejné zdroje Keywords : electric double layer * cassiterite * water Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.009, year: 2007

  1. Influence of soil pedological properties on termite mound stability

    OpenAIRE

    Jouquet, Pascal; Guilleux, N.; Caner, L.; Chintakunta, S.; Ameline, M.; Shanbhag, R. R.

    2016-01-01

    This study investigated the influence of soil properties on the density and shape of epigeous fungus-growing termite nests in a dry deciduous forest in Karnataka, India. In this environment, Odontotermes obesus produces cathedral shaped mounds. Their density, shape (height and volume) and soil physicochemical properties were analyzed in ferralsol and vertisol environments. No significant difference was observed in O. obesus mound density (n = 2.7 mound ha(-1) on average in the vertisol and fe...

  2. Abundancia, tamaño y estructura poblacional del tiburón punta blanca de arrecife, Triaenodon obesus (Carcharhiniformes: Carcharhinidae, en Bahía Chatham, Parque Nacional Isla del Coco, Costa Rica

    Directory of Open Access Journals (Sweden)

    Ilena Zanella

    2012-11-01

    Full Text Available Doce especies de tiburones habitan las aguas del Parque Nacional Isla del Coco (PNIC y uno de los más abundantes es el tiburón punta blanca de arrecife, Triaenodon obesus. El presente estudio determinó la abundancia, tallas y estructura de la población de esta especie en la zona de Bahía Chatham, PNIC. Se utilizó el método de marcaje y recaptura y se realizaron conteos subacuáticos visuales, con el fin de determinar su abundancia relativa y contabilizar recapturas visuales. Los tiburones punta blanca de Bahía Chatham no presentan segregación ontogénica espacial definida; pero si una alta fidelidad a los a sitios de residencia dentro de esta bahía. La longitud total promedio de los tiburones marcados fue de 101.8±12.1cm, con una longitud total máxima de 130.0cm y una mínima de 71.0cm. La mediana de las longitudes totales de los tiburones machos (103.5±21.33cm y hembras (100.1±11.2cm no difirieron significativamente (H = 1.78; p=0.1818. La abundancia relativa en Bahía Chatham, PNIC fue de 49.5±10.4 tiburones/h. El tamaño estimado de la población usando el método de de captura-recaptura fue de 408 (IC=181-1050.

  3. UTILITY OF FISHERY HIGH SCHOOL DATA IN EXAMINING SPATIAL AND TEMPORAL CATCH AND EFFORT TRENDS IN THE INDONESIAN LONGLINE TUNA FISHERY

    Directory of Open Access Journals (Sweden)

    Lilis Sadiyah

    2015-12-01

    Full Text Available One of the endeavours to address the shortage of catch per unit effort (CPUE information from the Indonesian Indian Ocean tuna fishery is the collation of a large amount of catch and effort data collected by Indonesian Fisheries High School students (“FHS data”. This paper attempts to investigate spatial-temporal patterns of catch and effort of the FHS data for the main tuna species caught by the fishery: bigeye tuna (Thunnus obesus - BET, yellowfin tuna (T. albacares - YFT, albacore (T. alalunga - ALB and southern bluefin tuna (T.maccoyii - SBT. Reported sets occurred in the Eastern Indian Ocean, north and south of 20°S. Recorded effort from the FHS data set was concentrated within the only known SBT spawning ground. However, within this data set, SBT were recorded in the lowest catch proportion relative to BET, YFT and ALB. The catch composition data suggested that YFT and ALB were predominantly targeted by the fishery, with ALB and SBT most predominantly recorded south of 20°S, whereas BET and YFT were mostly recorded north of 20°S. Unfortunately, there was no strong information on targeting practices reported by this data set, limiting any attempts to understand the factors that influenced those results. As the sampling predominantly occurred in between July and December, the data are not representative of fishing activities throughout the entire year, and any seasonal patterns from the FHS data set are biased. In addition, the FHS data set is prone to observation error and uncertainty in terms of fish identification and fishing location. Therefore, the FHS data set needs to be interpreted with caution.

  4. Diurnal rodents as animal models of human central vision: characterisation of the retina of the sand rat Psammomys obsesus.

    Science.gov (United States)

    Saïdi, Tounès; Mbarek, Sihem; Chaouacha-Chekir, Rafika Ben; Hicks, David

    2011-07-01

    Cone photoreceptor-based central vision is of paramount importance in human eyesight, and the increasing numbers of persons affected by macular degeneration emphasizes the need for relevant and amenable animal models. Although laboratory mice and rats have provided valuable information on retinal diseases, they have inherent limitations for studies on macular pathology. In the present study, we extend our recent analyses of diurnal murid rodents to demonstrate that the sand rat Psammomys obesus has a remarkably cone-rich retina, and represents a useful adjunct to available animal models of central vision. Adult P. obesus were captured and transferred to animal facilities where they were maintained under standard light/dark cycles. Animals were euthanised and their eyes enucleated. Tissue was either fixed in paraformaldehyde and prepared for immunohistochemistry, or solubilized in lysis buffer and separated by SDS-PAGE and subjected to western blot analysis. Samples were labelled with a battery of antibodies against rod and cone photoreceptors, inner retinal neurones, and glia. P. obesus showed a high percentage of cones, 41% of total photoreceptor numbers in both central and peripheral retina. They expressed multiple cone-specific proteins, including short and medium-wavelength opsin and cone transducin. A second remarkable feature of the retina concerned the horizontal cells, which expressed high levels of glial fibrillar acidic protein and occludin, two proteins which are not seen in other species. The retina of P. obesus displays high numbers of morphologically and immunologically identifiable cones which will facilitate analysis of cone pathophysiology in this species. The unusual horizontal cell phenotype may be related to the cone distribution or to an alternative facet of the animals lifestyle.

  5. Temporal dynamics and impact of climate factors on the incidence of zoonotic cutaneous leishmaniasis in central Tunisia.

    Directory of Open Access Journals (Sweden)

    Amine Toumi

    Full Text Available Old world Zoonotic Cutaneous Leishmaniasis (ZCL is a vector-borne human disease caused by Leishmania major, a unicellular eukaryotic parasite transmitted by pool blood-feeding sand flies mainly to wild rodents, such as Psammomys obesus. The human beings who share the rodent and sand fly habitats can be subverted as both sand fly blood resource. ZCL is endemic in the Middle East, Central Asia, Subsaharan and North Africa. Like other vector-borne diseases, the incidence of ZCL displayed by humans varies with environmental and climate factors. However, so far no study has addressed the temporal dynamics or the impact of climate factors on the ZCL risk.Seasonality during the same epidemiologic year and interval between ZCL epidemics ranging from 4 to 7 years were demonstrated. Models showed that ZCL incidence is raising i by 1.8% (95% confidence intervals CI:0.0-3.6% when there is 1 mm increase in the rainfall lagged by 12 to 14 months ii by 5.0% (95% CI: 0.8-9.4% when there is a 1% increase in humidity from July to September in the same epidemiologic year.Higher rainfall is expected to result in increased density of chenopods, a halophytic plant that constitutes the exclusive food of Psammomys obesus. Consequently, following a high density of Psammomys obesus, the pool of Leishmania major transmissible from the rodents to blood-feeding female sand flies could lead to a higher probability of transmission to humans over the next season. These findings provide the evidence that ZCL is highly influenced by climate factors that could affect both Psammomys obesus and the sand fly population densities.

  6. Karakteristik Ikan Tuna sirip biru selatan (Thunnus maccoyii Hasil Tangkapan Kapal Rawai Tuna yang didaratkan di Pelabuhan Benoa

    Directory of Open Access Journals (Sweden)

    I Gede Adi Swastana

    2016-07-01

    Full Text Available Southern bluefin tuna (SBT is scientifically known Thunnus maccoyii, and just live in the southern hemisphere. SBT fish classified as the most exploited tuna fish in the southeastern part of the Indian Ocean, so it is protected by the International Union for the Conservation of Nature (IUCN. The aim of this study is too collected of SBT fish caught during January which is the peak of SBT landing in Benoa port. The study was conducted base on data sampling, observation and interviews on 33 ships were landing SBT fish during January 2016. Based on observations from 33 vessels, we found that the total of SBT fish that landed in Benoa port during January 2016 is 251 fresh fish and 366 frozen fish. However just 251 SBT fresh fish were sampled, and the result indicated the fresh SBT fish is dominated by weigh between 61-70 kg with number 61 fish with a total weight of 19.28 tonne. The SBT were caught dominated by fish that has FL (fork lenght ranging between 151-160 cm with number 69 fish. While the smallest SBT range between 131-140 cm with the number of 5 fish. These results indicate that SBT fish caught in the Souetheast Indian Ocean during January 2016 is generaly relative small fish (130–160 cm FL with a number of 163 fish and mature SBT fish (FL > 162 cm with a number of 88 and young SBT (FL < 130 cm with a number of 5 fish. Based on morphometric analysis, eyeball diameter of SBT range 6-8 cm, the length lateral head from the tip of the mouth to behind the gill cover ranging 46-54 cm, the length of body from the early dorsal or in front of the first dorsal fin ranging between 38-47 cm, the height of fish at the end of the anal or at the end ranging between 34-39 cm, the high of caudal peduncle ranging between 4-5 cm, th length of the dorsal base of the tail fish ranging between 53-63 cm, and the length of the base of tail anal from anal to tail ranging between 41-51 cm. Base on size and age composition, it is shown that the growth of SBT

  7. Karakteristik Ikan Tuna sirip biru selatan (Thunnus maccoyii Hasil Tangkapan Kapal Rawai Tuna yang didaratkan di Pelabuhan Benoa

    Directory of Open Access Journals (Sweden)

    I Gede Adi Swastana

    2016-12-01

    Full Text Available Southern bluefin tuna (SBT is scientifically known Thunnus maccoyii, and just live in the southern hemisphere. SBT fish classified as the most exploited tuna fish in the southeastern part of the Indian Ocean, so it is protected by the International Union for the Conservation of Nature (IUCN. The aim of this study is too collected of SBT fish caught during January which is the peak of SBT landing in Benoa port. The study was conducted base on data sampling, observation and interviews on 33 ships were landing SBT fish during January 2016. Based on observations from 33 vessels, we found that the total of SBT fish that landed in Benoa port during January 2016 is 251 fresh fish and 366 frozen fish. However just 251 SBT fresh fish were sampled, and the result indicated the fresh SBT fish is dominated by weigh between 61-70 kg with number 61 fish with a total weight of 19.28 tonne. The SBT were caught dominated by fish that has FL (fork lenght ranging between 151-160 cm with number 69 fish. While the smallest SBT range between 131-140 cm with the number of 5 fish. These results indicate that SBT fish caught in the Souetheast Indian Ocean during January 2016 is generaly relative small fish (130–160 cm FL with a number of 163 fish and mature SBT fish (FL > 162 cm with a number of 88 and young SBT (FL < 130 cm with a number of 5 fish. Based on morphometric analysis, eyeball diameter of SBT range 6-8 cm, the length lateral head from the tip of the mouth to behind the gill cover ranging 46-54 cm, the length of body from the early dorsal or in front of the first dorsal fin ranging between 38-47 cm, the height of fish at the end of the anal or at the end ranging between 34-39 cm, the high of caudal peduncle ranging between 4-5 cm, th length of the dorsal base of the tail fish ranging between 53-63 cm, and the length of the base of tail anal from anal to tail ranging between 41-51 cm. Base on size and age composition, it is shown that the growth of SBT

  8. Stereological comparison of oocyte recruitment and batch fecundity estimates from paraffin and resin sections using spawning albacore (Thunnus alalunga) ovaries as a case study

    Science.gov (United States)

    Saber, Sámar; Macías, David; Ortiz de Urbina, Josetxu; Kjesbu, Olav Sigurd

    2015-01-01

    Traditional histological protocols in marine fish reproductive laboratories using paraffin as the embedding medium are now increasingly being replaced with protocols using resin instead. These procedures entail different degrees of tissue shrinkage complicating direct comparisons of measurement results across laboratories or articles. In this work we selected ovaries of spawning Mediterranean albacore (Thunnus alalunga) as the subject of our study to address the issue of structural changes, by contrasting values on oocyte recruitment and final batch fecundity given from the same tissue samples in both paraffin and resin. A modern stereological method, the oocyte packing density (OPD) theory, was used supported by initial studies on ovarian tissue sampling and measurement design. Examples of differences in the volume fraction of oocyte stages, free space and connective tissue were found between the embedding media. Mean oocyte diameters were smaller in paraffin than in resin with differences ranging between 0.5% in primary growth and 24.3% in hydration (HYD) stage oocytes. Fresh oocyte measurements showed that oocytes shrank as a consequence of the embedding process, reaching the maximal degree of shrinkage for oocytes in the HYD stage (45.8% in paraffin and 26.5% in resin). In order to assess the effect of oocyte shrinkage on the OPD result, and thereby on relative batch fecundity (Fr), oocyte diameters corrected and uncorrected for shrinkage, were used for estimations. Statistical significant differences were found (P based on either oocytes in the germinal vesicle migration stage or HYD stage. As a valuable adjunct, the present use of the OPD theory made it possible to document that the oocyte recruitment of spawning ovaries of Mediterranean albacore followed the typical pattern of an asynchronous oocyte development and indeterminate fecundity.

  9. The transition from day-to-night activity is a risk factor for the development of CNS oxygen toxicity in the diurnal fat sand rat (Psammomys obesus).

    Science.gov (United States)

    Eynan, Mirit; Biram, Adi; Mullokandov, Michael; Kronfeld-Schor, Noga; Paz-Cohen, Rotem; Menajem, Dvir; Arieli, Yehuda

    2017-01-01

    Performance and safety are impaired in employees engaged in shift work. Combat divers who use closed-circuit oxygen diving apparatus undergo part of their training during the night hours. The greatest risk involved in diving with such apparatus is the development of central nervous system oxygen toxicity (CNS-OT). We investigated whether the switch from day-to-night activity may be a risk factor for the development of CNS-OT using a diurnal animal model, the fat sand rat (Psammomys obesus). Animals were kept on a 12:12 light-dark schedule (6 a.m. to 6 p.m. at 500 lx). The study included two groups: (1) Control group: animals were kept awake and active during the day, between 09:00 and 15:00. (2) Experimental group: animals were kept awake and active during the night, between 21:00 and 03:00, when they were exposed to dim light in order to simulate the conditions prevalent during combat diver training. This continued for a period of 3 weeks, 5 days a week. On completion of this phase, 6-sulphatoxymelatonin (6-SMT) levels in urine were determined over a period of 24 h. Animals were then exposed to hyperbaric oxygen (HBO). To investigate the effect of acute melatonin administration, melatonin (50 mg/kg) or its vehicle was administered to the animals in both groups 20 min prior to HBO exposure. After the exposure, the activity of superoxide dismutase, catalase and glutathione peroxidase was measured, as were the levels of neuronal nitric oxide synthase (nNOS) and overall nitrotyrosylation in the cortex and hippocampus. Latency to CNS-OT was significantly reduced after the transition from day-to-night activity. This was associated with alterations in the level of melatonin metabolites secreted in the urine. Acute melatonin administration had no effect on latency to CNS-OT in either of the groups. Nevertheless, the activity of superoxide dismutase and catalase, as well as nitrotyrosine and nNOS levels, were altered in the hippocampus following melatonin

  10. Didymocystis lamotheargumedoi n. sp. (Digenea:Didymozoidae a parasite of three species of scombrid fishes Didymocystis lamotheargumedoi n. sp. (Digenea:Didymozoidae parásito de tres especies de peces escómbridos

    Directory of Open Access Journals (Sweden)

    Anna Kohn

    2008-08-01

    Full Text Available Didymocystis lamotheargumedoi n. sp. is described from the operculum and palate of Thunnus atlanticus (Lesson, 1831, palate of Thunnus albacares (Bonnaterre, 1788, and the operculum of Katsuwonus pelamis (Linnaeus, 1758 caught on the coast of Rio de Janeiro, Brazil. The new species is most similar to D. alalongae (Yamaguti, 1938, D. exiguus (Yamaguti, 1970, and D. oesophagicola (Yamaguti, 1970, based on the vitelline and ovarian branches lacking ramifications. It variously differs from these 3 species in the number of ovarian and vitelline branches, the length of the vitelline branches, egg size, body size and site within the host. Immature forms associated with adults are also described.Didymocystis lamotheargumedoi n. sp. se describe como parásito del opérculo y del paladar de Thunnus atlanticus (Lesson, 1831, del paladar de Thunnus albacares (Bonnaterre, 1788 y del opérculo de Katsuwonus pelamis (Linnaeus, 1758 capturados en la costa de Rio de Janeiro, Brasil. La especie nueva es semejante a D. alalongae (Yamaguti, 1938, D. exiguus (Yamaguti, 1970 y D. oesophagicola (Yamaguti, 1970, por la ausencia de ramificaciones en las vitelógenas y en los ovarios. Estas 3 especies difieren en el número de ramificaciones de las vitelógenas y ovarios, en la longitud de ramificaciones de las vitelógenas, tamaño del cuerpo y sitio dentro del hospedador. Se describen también las formas inmaduras asociadas con sus respectivas formas adultas.

  11. African Journal of Biotechnology - Vol 14, No 20 (2015)

    African Journals Online (AJOL)

    Cellulolytic activity of gut extract of subterranean termite, Odontotermes obesus Rambur: A pretreatment tool for conversion of lignocellulosic biomass to fermentable sugar for biorefinery industry · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. N Senthilkumar, S ...

  12. Correlation Between Existence of Reef Sharks with Abundance of Reef Fishes in South Waters of Morotai Island (North Moluccas)

    Science.gov (United States)

    Mukharror, Darmawan Ahmad; Tiara Baiti, Isnaini; Ichsan, Muhammad; Pridina, Niomi; Triutami, Sanny

    2017-10-01

    Despite increasing academic research citation on biology, abundance, and the behavior of the blacktip reef sharks, the influence of reef fish population on the density of reef sharks: Carcharhinus melanopterus and Triaenodon obesus population in its habitat were largely unassessed. This present study examined the correlation between abundance of reef fishes family/species with the population of reef sharks in Southern Waters of Morotai Island. The existence of reef sharks was measured with the Audible Stationary Count (ASC) methods and the abundance of reef fishes was surveyed using Underwater Visual Census (UVC) combined with Diver Operated Video (DOV) census. The coefficient of Determination (R2) was used to investigate the degree of relationships between sharks and the specific reef fishes species. The research from 8th April to 4th June 2015 showed the strong positive correlations between the existence of reef sharks with abundance of reef fishes. The correlation values between Carcharhinus melanopterus/Triaenodon obesus with Chaetodon auriga was 0.9405, blacktip/whitetip reef sharks versus Ctenochaetus striatus was 0.9146, and Carcharhinus melanopterus/Triaenodon obesus to Chaetodon kleinii was 0.8440. As the shark can be worth more alive for shark diving tourism than dead in a fish market, the abundance of these reef fishes was important as an early indication parameter of shark existence in South Water of Morotai Island. In the long term, this highlights the importance of reef fishes abundance management in Morotai Island’s Waters to enable the establishment of appropriate and effective reef sharks conservation.

  13. Effect of whole body gamma-irradiation and/or dietary protein deficiency on the levels of plasma non-protein nitrogen and amino acids; plasma and urinary ammonia and urea in desert rodent and albino rats

    International Nuclear Information System (INIS)

    Roushdy, H.M.; El-Husseini, M.; Saleh, F.

    1984-01-01

    The effect of gamma-irradiation exposure on the levels of non-protein nitrogen (N.P.N.) and amino acids in plasma; ammonia and urea in plasma and urine was studied in the desert rodent, Psammomys obesus obesus and albino rats subjected to dietary protein deficiency, N.P.N. and amino acids in plasma were shown to increase by irradiation exposure. The effect of radiation on blood ammonia was less marked, but it caused a significant increase in ammonia excretion in urine. Radiation exposure in albino rats caused a marked increase in urea concentration in plasma of animals fed the high protein diet and irradiated at 780 r. In urine, the tested radiation levels caused an initial increase in urea concentration followed by a subsequent decrease. In psammomys, radiation exposure exerted a little effect on the plasma urea level, whereas significant increase in the daily urea excretion was recorded. It seems that urea level in plasma is more stabilized in psammomys than in albino rats

  14. Browse Title Index

    African Journals Online (AJOL)

    Vol 14, No 20 (2015), Cellulolytic activity of gut extract of subterranean termite, Odontotermes obesus Rambur: A pretreatment tool for conversion of lignocellulosic biomass to fermentable sugar for biorefinery industry, Abstract PDF. N Senthilkumar, S Murugesan, DS Babu. 2001 - 2050 of 11090 Items, << < 36 37 38 39 40 ...

  15. Author Details

    African Journals Online (AJOL)

    Upadhyay, R. Vol 14, No 3 (2010) - Articles Anti-termite efficacy of Capparis decidua and its combinatorial mixtures for the control of Indian white termite Odontotermes obesus (Isoptera: Odontotermitidae) in Indian soil. Abstract PDF. ISSN: 1119-8362. AJOL African Journals Online. HOW TO USE AJOL... for Researchers ...

  16. Habitat use, vertical and horizontal behaviour of Atlantic bluefin tuna (Thunnus thynnus) in the Northwestern Mediterranean Sea in relation to oceanographic conditions

    Science.gov (United States)

    Bauer, Robert Klaus; Fromentin, Jean-Marc; Demarcq, Hervé; Bonhommeau, Sylvain

    2017-07-01

    We investigated the habitat utilization, vertical and horizontal behaviour of Atlantic bluefin tuna Thunnus thynnus (ABFT) in relation to oceanographic conditions in the northwestern Mediterranean Sea, based on 36 pop-up archival tags and different environmental data sets. Tags were deployed on early mature ABFT (127-255 cm) between July and November in 2007-2014, on the shelf area off Marseille, France. The data obtained from these tags provided 1643 daily summaries of ABFT vertical behaviour over 8 years of tag deployment. Based on a hierarchical clustering of this data, we could identify four principle daily vertical behaviour types, representing surface (≦ 10 m) and subsurface (10-100 m) orientation, moderate (50-200 m) and deep (≧ 200 m) diving behaviour. These vertical behaviour types showed seasonal variations with partly opposing trends in their frequencies. Accordingly, ABFT were more surface orientated during summer, while moderate diving behaviour was more common during winter. Depth time series data further revealed inverted day-night patterns for both of these periods. Tagged ABFT frequented the surface waters more regularly during daytime and deeper waters during the night in summer, while the opposite pattern was found in winter. Seasonal changes in the vertical behaviour of ABFT were accompanied by simultaneous changes in environmental conditions (SST, chla, thermal stratification). Accordingly, surface orientation and moderate diving behaviour appeared to be triggered by the thermal stratification of the water column, though less pronounced than previously reported for ABFT in the North Atlantic, probably indicating adaptive vertical behaviour related to the availability of epipelagic food resources (anchovies and sardines). Deep diving behaviour was particularly frequent during months of high biological productivity (February-May), although one recovered tag showed periodic and unusual long spike dives during summer-autumn, in relation to

  17. RAD-seq derived genome-wide nuclear markers resolve the phylogeny of tunas

    KAUST Repository

    Díaz-Arce, Natalia

    2016-06-07

    Although species from the genus Thunnus include some of the most commercially important and most severely overexploited fishes, the phylogeny of this genus is still unresolved, hampering evolutionary and traceability studies that could help improve conservation and management strategies for these species. Previous attempts based on mitochondrial and nuclear markers were unsuccessful in inferring a congruent and reliable phylogeny, probably due to mitochondrial introgression events and lack of enough phylogenetically informative markers. Here we infer the first genome-wide nuclear marker-based phylogeny of tunas using restriction site associated DNA sequencing (RAD-seq) data. Our results, derived from phylogenomic inferences obtained from 128 nucleotide matrices constructed using alternative data assembly procedures, support a single Thunnus evolutionary history that challenges previous assumptions based on morphological and molecular data.

  18. Estabilidad en el almacenamiento congelado de rebanadas de lomo de atún rojo (Thunnus sp. empacadas en atmósfera modificada con CO2

    Directory of Open Access Journals (Sweden)

    Myrna Luisa Medina Bracamonte

    2014-12-01

    Full Text Available La disponibilidad atún rojo fresco, entero y rebanado, como todo producto pesquero fresco está restringida para los consumidores en zonas distantes a los centros de producción por su estabilidad limitada en el almacenamiento. Por ello la industria pesquera en general, en la época de mayor producción, recurre a la congelación para conservar el excedente de producción, y al empacado para protegerlo del ambiente frío y seco del congelador, evitar su deshidratación y “quemaduras por frío”. El surgimiento del Empacado en Atmósfera Modificada como alternativa para incrementar la vida útil de productos alimenticios despertó la inquietud de evaluar la estabilidad de rebanadas de lomo de atún rojo (Thunnus sp. fresco, congeladas y empacadas con 100 % de CO2 durante su almacenamiento a las temperaturas convencionales para su distribución y venta, -10 y -18 ºC, evaluando la estabilidad química, física, microbiológica y sensorial de las rebanadas de lomo de atún rojo durante ≈ 4 meses de almacenamiento congelado. El 50 % de las rebanadas se congeló a -10 ºC (Tratamiento 1 y el 50 % restante a -18 ºC (Tratamiento 2. Las rebanadas congeladas se empacaron individualmente, el 50 % en atmósfera de 100 % de CO2 conservando la proporción 1:2 (rebanada:gas y el 50 % restante en atmósfera de aire. Se almacenaron a la temperatura correspondiente: Tratamiento 1 a -10 ºC y Tratamiento 2 a -18 ºC durante 111 días. Al final del almacenamiento el tratamiento P2 (100 % CO2 ofreció mejor barrera a la pérdida de humedad, favoreció la estabilidad de la fracción de proteínas solubles en solución salina. Las muestras P2 tuvieron mayor aceptación sensorial, fueron las más oscuras y rojas, con menor recuento microbiológico, coincidiendo con el menor contenido en bases volátiles totales. A -10 ºC la atmósfera de 100 % de CO2 no evitó la “quemadura por frío” y los panelistas percibieron el “olor a pescado”.

  19. The amphipod genus Acidostoma

    NARCIS (Netherlands)

    Dahl, E.

    1964-01-01

    The genus Acidostoma was established by Lilljeborg (1865, p. 24) to receive Anonyx obesus Sp. Bate (1862, p. 74). Afterwards two further species have been added, viz. A. laticorne G. O. Sars (1879, p. 440) and A. nodiferum Stephensen (1923, p. 40). In the present paper it will be shown that A.

  20. A spatial ecosystem and populations dynamics model (SEAPODYM) Modeling of tuna and tuna-like populations

    Science.gov (United States)

    Lehodey, Patrick; Senina, Inna; Murtugudde, Raghu

    2008-09-01

    An enhanced version of the spatial ecosystem and population dynamics model SEAPODYM is presented to describe spatial dynamics of tuna and tuna-like species in the Pacific Ocean at monthly resolution over 1° grid-boxes. The simulations are driven by a bio-physical environment predicted from a coupled ocean physical-biogeochemical model. This new version of SEAPODYM includes expanded definitions of habitat indices, movements, and natural mortality based on empirical evidences. A thermal habitat of tuna species is derived from an individual heat budget model. The feeding habitat is computed according to the accessibility of tuna predator cohorts to different vertically migrating and non-migrating micronekton (mid-trophic) functional groups. The spawning habitat is based on temperature and the coincidence of spawning fish with presence or absence of predators and food for larvae. The successful larval recruitment is linked to spawning stock biomass. Larvae drift with currents, while immature and adult tuna can move of their own volition, in addition to being advected by currents. A food requirement index is computed to adjust locally the natural mortality of cohorts based on food demand and accessibility to available forage components. Together these mechanisms induce bottom-up and top-down effects, and intra- (i.e. between cohorts) and inter-species interactions. The model is now fully operational for running multi-species, multi-fisheries simulations, and the structure of the model allows a validation from multiple data sources. An application with two tuna species showing different biological characteristics, skipjack ( Katsuwonus pelamis) and bigeye ( Thunnus obesus), is presented to illustrate the capacity of the model to capture many important features of spatial dynamics of these two different tuna species in the Pacific Ocean. The actual validation is presented in a companion paper describing the approach to have a rigorous mathematical parameter optimization

  1. Estabilidad química, física y microbiológica de lomo de atún (Thunnus sp. rebanado. Empacado, congelado y almacenado a -20 ºC

    Directory of Open Access Journals (Sweden)

    Romaim De Berardinis

    2012-12-01

    Full Text Available La globalización ha introducido en Venezuela el consumo de pescado crudo, principalmente atún rojo (Thunnus sp. para elaborar sushi y sashimi. Esto ha despertado el interés en conservar el atún fresco, congelado, para disponer de él a lo largo del año con los atributos que definen la calidad del atún fresco. El pescado congelado se empaca para protegerlo del ambiente frío y seco del congelador, evitar su deshidratación y quemaduras en la superficie del tejido muscular que modificarían la apariencia (color, textura, el sabor y el valor nutritivo durante el almacenamiento. El empaque, además debe ofrecer barrera al paso del oxígeno. Los filetes individuales de pescados magros pueden conservarse en almacenamiento congelado 6 meses a -18 ºC y hasta 9 meses a -24 ºC. Con este trabajo se propuso determinar el efecto del la operación de empacado antes y después de la operación de congelación de rebanadas de lomo de atún rojo. Tratamiento 1: empacadas al vacío y congeladas a -20 ºC (V1; control: empacadas a presión atmosférica y congeladas a -20 ºC (C1. Tratamiento 2: congeladas a -20 ºC y empacadas al vacío después (V2; control: congeladas a -20 ºC y empacadas a presión atmosférica después (C2. Para el empacado se recurrió a bolsas multilaminadas (PE/PA/PE, impermeables al O2 del aire, al vapor de agua y con resistencia mecánica a bajas temperaturas. El tratamiento V1 mantuvo la estabilidad química, microbiológica y sensorial de las rebanadas de lomo de atún, a 90 días de almacenamiento a -20 ºC, la cuales fueron más rojas (a, menos amarillas (b y más oscuras (L, con la menor producción de malonaldehído (0,64 mg/kg de todos los tratamientos, y la mayor estabilidad de la fracción de proteínas solubles (10,03 %.

  2. Estabilidad química, física y microbiológica de lomo de atún (Thunnus sp. rebanado. Empacado, congelado y almacenado a -20 ºC

    Directory of Open Access Journals (Sweden)

    Romaim De Berardinis

    2012-01-01

    Full Text Available La globalización ha introducido en Venezuela el consumo de pescado crudo, principalmente atún rojo (Thunnus sp. para elaborar sushi y sashimi. Esto ha despertado el interés en conservar el atún fresco, congelado, para disponer de él a lo largo del año con los atributos que definen la calidad del atún fresco. El pescado congelado se empaca para protegerlo del ambiente frío y seco del congelador, evitar su deshidratación y quemaduras en la superficie del tejido muscular que modificarían la apariencia (color, textura, el sabor y el valor nutritivo durante el almacenamiento. El empaque, además debe ofrecer barrera al paso del oxígeno. Los filetes individuales de pescados magros pueden conservarse en almacenamiento congelado 6 meses a -18 ºC y hasta 9 meses a -24 ºC. Con este trabajo se propuso determinar el efecto del la operación de empacado antes y después de la operación de congelación de rebanadas de lomo de atún rojo. Tratamiento 1: empacadas al vacío y congeladas a -20 ºC (V1; control: empacadas a presión atmosférica y congeladas a -20 ºC (C1. Tratamiento 2: congeladas a -20 ºC y empacadas al vacío después (V2; control: congeladas a -20 ºC y empacadas a presión atmosférica después (C2. Para el empacado se recurrió a bolsas multilaminadas (PE/PA/PE, impermeables al O2 del aire, al vapor de agua y con resistencia mecánica a bajas temperaturas. El tratamiento V1 mantuvo la estabilidad química, microbiológica y sensorial de las rebanadas de lomo de atún, a 90 días de almacenamiento a -20 ºC, la cuales fueron más rojas (a, menos amarillas (b y más oscuras (L, con la menor producción de malonaldehído (0,64 mg/kg de todos los tratamientos, y la mayor estabilidad de la fracción de proteínas solubles (10,03 %.

  3. Modificaciones en la grasa del atún blanco (Thunnus alalunga debidas a la fabricación y almacenamiento de su conserva

    Directory of Open Access Journals (Sweden)

    Navarro, María P.

    1991-06-01

    Full Text Available Modifications in fatty acid composition in white tuna (Thunnus alalunga ocurring at each stage of the cannig process, boiling and sterilization in soybean oil, were studied. Boiling was performed in brine and two sterilization times (55 and 90 minutes as well as the effects of storage for one year were tested. Boiling had no effect on fatty acid composition or the n-3/n-6 ratio. However canned tuna absorbed soybean oil during sterilization, causing an increase of the percentage of C18:1, C18:2 and C18:3 and a decrease in C20:5 and C22:6. Therefore, unsaturated fatty acids to saturated fatty acids (PS/S ratio changed and the n-3/n-6 ratio declined from 7.03 to 0.59 compared with raw tuna. Due to the whole fat enrichment, canned fish showed a slight loss of PUFA (C20:5 and C22:6 and a increase of C18:1, C18:2 and C18:3. The latter effect was more marked in the preserves as a consequence of one year storage. The convenience of using for cannig an oil containing a lower amount of polyunsaturated fatty acid in order to remain the original n-3/n-6 ratio of the raw tuna is discussed.Se estudiaron los cambios que se producen en la grasa del atún blanco en cada una de las etapas que intervienen en el proceso de fabricación y almacenamiento de su conserva: cocción en salmuera y esterilización practicada en aceite de soja. Se estudiaron dos tiempos diferentes de esterilización (55 y 90 minutos y el almacenamiento por espacio de 1 año. La cocción en salmuera no afectó a la composición en ácidos grasos de los lípidos del pescado ni a la relación n-3/n-6. Sin embargo, durante la esterilización, el atún absorbió el aceite utilizado como cobertura, lo que produjo un aumento porcentual en el nivel de C18:1, C18:2, C18:3 y una disminución en C20:5 y C22:6. La relación ácidos grasos insaturados a saturados (PS/S cambió y la n-3/n-6 disminuyó desde 7,03 a 0,59 comparado con atún crudo. En el pescado en conserva, debido al enriquecimiento total

  4. Cytochrome Oxidase I (COI) sequence conservation and variation patterns in the yellowfin and longtail tunas

    Digital Repository Service at National Institute of Oceanography (India)

    Kunal, S.P.; GirishKumar

    within and between tuna Thunnus species and its application to species identification. J Fish Biol. 58, 1646–1657. 8 Terol, J., Mascarell, R., Fernandez-Pedrosa, V., Perez-Alonso, M. (2002) Statistical validation of the identification of tuna...

  5. Spawning of bluefin tuna in the black sea: historical evidence, environmental constraints and population plasticity

    DEFF Research Database (Denmark)

    Mackenzie, Brian R; Mariani, Patrizio

    2012-01-01

    The lucrative and highly migratory Atlantic bluefin tuna, Thunnus thynnus (Linnaeus 1758; Scombridae), used to be distributed widely throughout the north Atlantic Ocean, Mediterranean Sea and Black Sea. Its migrations have supported sustainable fisheries and impacted local cultures since antiquity...

  6. Comparative ecology of widely distributed pelagic fish species in the North Atlantic: Implications for modelling climate and fisheries impacts

    DEFF Research Database (Denmark)

    Trenkel, V.M.; Huse, G.; MacKenzie, Brian

    2014-01-01

    (Thunnus thynnus), swordfish (Xiphias gladius), and blue marlin (Makaira nigricans), which, by contrast, show large-scale migrations at the basin scale. We focus on the links between life history processes and the environment, horizontal and vertical distribution, spatial structure and trophic role. Many...

  7. Proactive Conservation Program: Species of Concern :: NOAA Fisheries

    Science.gov (United States)

    Invertebrates & Plants Species of Concern Threatened & Endangered Health & Stranding Marine Mammals : Species of Concern Species of Concern List | Grants and Technical Resources/Links bluefin tuna Bluefin Tuna (Thunnus thynnus) Photo: NOAA Species of Concern are those species about which we have some

  8. 76 FR 31556 - Endangered and Threatened Wildlife and Plants; Endangered Species Act Listing Determination for...

    Science.gov (United States)

    2011-06-01

    ... Atlantic bluefin tuna (Thunnus thynnus) as threatened or endangered under the Endangered Species Act (ESA... Species Act Listing Determination for Atlantic Bluefin Tuna AGENCY: National Marine Fisheries Service... endangered species within the foreseeable future throughout all or a significant portion of its range.'' The...

  9. Determination of cadmium, lead and mercury residual levels in meat ...

    African Journals Online (AJOL)

    Determination of cadmium, lead and mercury residual levels in meat of canned light tuna ( Katsuwonus pelamis and Thunnus albacares ) and fresh little tunny ( Euthynnus alletteratus ) in Libya. ... Surveillance for mercury (Hg), lead (Pb) and cadmium (Cd) contamination in tuna products is crucial for consumer food safety.

  10. The Southern Oscillation, Hypoxia, and the Eastern Pacific Tuna Fishery

    Science.gov (United States)

    Webster, D.; Kiefer, D.; Lam, C. H.; Harrison, D. P.; Armstrong, E. M.; Hinton, M.; Luo, L.

    2012-12-01

    The Eastern Pacific tuna fishery, which is one of the world's major fisheries, covers thousands of square kilometers. The vessels of this fishery are registered in more than 30 nations and largely target bigeye (Thunnus obesus), skipjack (Katsuwonus pelamis), and yellowfin (T. albacores) tuna. In both the Pelagic Habitat Analysis Module project, which is sponsored by NASA, and the Fishscape project, which is sponsored by NSF, we have attempted to define the habitat of the three species by matching a 50 year time series on fish catch and effort with oceanographic information obtained from satellite imagery and from a global circulation model. The fishery time series, which was provided by the Inter-American Tropical Tuna Commission, provided spatial maps of catch and effort at monthly time steps; the satellite imagery of the region consisted of sea surface temperature, chlorophyll, and height from GHRSST, SEAWiFS, and AVISO products, and the modeled flow field at selected depths was output from ECCO-92 simulations from 1992 to present. All information was integrated and analyzed within the EASy marine geographic information system. This GIS will also provides a home for the Fishscape spatial simulation model of the coupled dynamics of the ocean, fish, fleets, and markets. This model will then be applied to an assessment of the potential ecological and economic impacts of climate change, technological advances in fleet operations, and increases in fuel costs. We have determined by application of EOF analysis that the ECCO-2 simulation of sea surface height fits well with that of AVISO imagery; thus, if driven properly by predictions of future air-sea exchange, the model should provide good estimates of circulation patterns. We have also found that strong El Nino events lead to strong recruitment of all three species and strong La Nina events lead to weak recruitment. Finally, we have found that the general spatial distribution of the Eastern Pacific fishing grounds

  11. Laboratory and field evaluation of Metarhizium anisopliae var. anisopliae for controlling subterranean termites

    OpenAIRE

    Hussain, A; Ahmed, S; Shahid, M

    2011-01-01

    The efficacy of the Metarhizium anisopliae strain ARSEF 6911 was determined in the laboratory and field against two sugarcane pests, Microtermes obesi Holmgren and Odontotermes obesus Rambur (Termitidae: Isoptera). The susceptibility of both termite species to different conidial suspensions (1 × 10(10), 1 × 10(8), 1 × 10(6) and 1 × 10(4) conidia/ml) was determined in laboratory. All conidial suspensions were able to induce mortality. Termite mortality caused by the fungal suspensions was dose...

  12. Pelagic shark bycatch in the tuna- and swordfish-directed longline ...

    African Journals Online (AJOL)

    The capture of pelagic sharks as bycatch of the South African pelagic longline fleet targeting tuna Thunnus spp. and swordfish Xiphias gladius was investigated during the period 1998–2005. In all, 26 species were caught, of which six are listed by the International Union for Conservation of Nature (IUCN) as Vulnerable and ...

  13. Hirudinella ventricosa (Pallas, 1774) Baird, 1853 represents a species complex based on ribosomal DNA.

    Science.gov (United States)

    Calhoun, Dana M; Curran, Stephen S; Pulis, Eric E; Provaznik, Jennifer M; Franks, James S

    2013-10-01

    Digeneans in the genus Hirudinella de Blainville, 1828 (Hirudinellidae) from three species of pelagic fishes, Acanthocybium solandri (Cuvier), Makaira nigricans Lacépède and Thunnus albacares (Bonnaterre), and one benthic fish, Mulloidichthys martinicus (Cuvier), from the Gulf of Mexico are investigated using comparison of ribosomal DNA. Four species are identified based on molecular differences: Hirudinella ventricosa (Pallas, 1774) Baird, 1853 from A. solandri, Hirudinella ahi Yamaguti, 1970 from T. albacares, and two unidentified but distinct species of Hirudinella, herein referred to as Hirudinella sp. A (from both M. nigricans and M. martinicus) and Hirudinella sp. B from M. nigricans. Additionally, H. ahi, based tentatively on morphological identification, is reported from Thunnus thynnus (Linnaeus). This represents the first record of a hirudinellid from M. martinicus and the first record of H. ahi from T. thynnus. A phylogeny of some Hemiurata Skrjabin & Guschanskaja, 1954 using partial fragments of the 28S rDNA sequences is consistent with earlier phylogenies and the position of the Hirudinellidae Dollfus, 1932 is well-supported as a derived group most closely related to the Syncoeliidae Looss, 1899.

  14. Update on Fish Disease Situation in Italy

    DEFF Research Database (Denmark)

    Vendramin, Niccolò; Toffan, A.

    2012-01-01

    In this presentation we provide a general overview of the aquatic animal health issues related to the aquaculture sector and wild environment in Italy in 2011. Considering saltwater species European sea bass (Dicentrarchus labrax) and Gilthead sea bream (Sparus aurata) are still the most widely...... (Thunnus thynnus) and amberjack (Seriola dumerilii) for which some breeding/reproduction plans have been attempted by some hatcheries. The farming of sea bass and sea bream is affected by the presence of several important diseases. Firstly considering Bacterial diseases, Marine Flexibacteriosis, caused...... main pathological scenarios are present. Farms with low water temperature (mainly located in the mountains) can be more affected and damaged by viral diseases (i.e. viral haemorrhagic septicaemia VHS) which is one of the most important problem. Rainbow trout fry syndrome (RTFS) is responsible...

  15. Turtle bycatch in the pelagic longline fishery off southern Africa ...

    African Journals Online (AJOL)

    Capture by pelagic longline fisheries has been identified as a key threat to turtle populations. This study is the first assessment of turtle bycatch in the South African pelagic longline fishery for tunas Thunnus spp. and swordfish Xiphias gladius. A total of 181 turtles was caught on observed sets between 1998 and 2005, at a ...

  16. FLUKTUASI DAN KOMPOSISI HASIL TANGKAPAN TUNA NERITIK TERTANGKAP JARING INSANG DI PERAIRAN LAUT CINA SELATAN

    Directory of Open Access Journals (Sweden)

    Arief Wujdi

    2016-03-01

    Full Text Available Saat ini tuna neritik merupakan komoditas penting perikanan di Indonesia, namun ketersediaan data dan informasi hasil tangkapan jenis tuna ini masih tergolong kurang. Penelitian ini bertujuan untuk memperoleh informasi mengenai sebaran daerah penangkapan, fluktuasi hasil tangkapan tuna neritik yang tertangkap jaring insang yang beroperasi di Laut Cina Selatan. Pengumpulan data dilakukan melalui program enumerasi monitoring hasil tangkapan harian di Pemangkat pada tahun 2011-2012. Hasil menunjukkan daerah penangkapan tersebar di perairan Laut Cina Selatan pada koordinat 01°03’ LS-04°57’ LU; dan 104°65’-110°00’ BT. Hasil tangkapan jenis tuna neritik menunjukan variasi yang cenderung sama dimana puncak hasil tangkapan terjadi pada bulan Oktober dan November. Pola CPUE berfluktuasi dan cenderung mengalami peningkatan dan puncaknya terjadi pada bulan November 2011 dan 2012, yaitu 402,85 dan 444,57 kg/hari/trip. Secara statistik hasil tangkapan pada periode 2011-2012 tidak berbeda nyata (p<0,05. Komposisi hasil tangkapan bulanan jenis tuna neritik bervariasi berdasarkan atas spesies yang didominasi oleh Euthynnus affinis (49,7% diikuti dengan Thunnus tonggol (33,4%; Scomberomorus commerson (15,9%; dan Scomberomorus guttatus (1%. Kelimpahan Euthynnus affinis terjadi pada musim timur hingga musim peralihan 2 (Juni- November, sedangkan kelimpahan Thunnus tonggol terjadi pada musim barat (Januari-Februari. Nowadays, neritic tuna just become an important commodity Indonesia. However, the information about catch of tuna neritic species in Indonesia still quite lacks. This This study aims to obtain information about catch fluctuation, monthly catch per unit of effort, and catch composition of neritic tuna species caught by gill net operated in the South China Sea. Data was collected by daily catch monitoring program by enumerator in Pemangkat during period 2011-2012. The result showed that gillnetter fishing ground is scattered between 01°03

  17. Preliminary forecasts of Pacific bigeye tuna population trends under the A2 IPCC scenario

    Science.gov (United States)

    Lehodey, P.; Senina, I.; Sibert, J.; Bopp, L.; Calmettes, B.; Hampton, J.; Murtugudde, R.

    2010-07-01

    An improved version of the spatial ecosystem and population dynamics model SEAPODYM was used to investigate the potential impacts of global warming on tuna populations. The model included an enhanced definition of habitat indices, movements, and accessibility of tuna predators to different vertically migrant and non-migrant micronekton functional groups. The simulations covered the Pacific basin (model domain) at a 2° × 2° geographic resolution. The structure of the model allows an evaluation from multiple data sources, and parameterization can be optimized by adjoint techniques and maximum likelihood using fishing data. A first such optimized parameterization was obtained for bigeye tuna ( Thunnus obesus) in the Pacific Ocean using historical catch data for the last 50 years and a hindcast from a coupled physical-biogeochemical model driven by the NCEP atmospheric reanalysis. The parameterization provided very plausible biological parameter values and a good fit to fishing data from the different fisheries, both within and outside the time period used for optimization. We then employed this model to forecast the future of bigeye tuna populations in the Pacific Ocean. The simulation was driven by the physical-biogeochemical fields predicted from a global marine biogeochemistry - climate simulation. This global simulation was performed with the IPSL climate model version 4 (IPSL-CM4) coupled to the oceanic biogeochemical model PISCES and forced by atmospheric CO 2, from historical records over 1860-2000, and under the SRES A2 IPCC scenario for the 21st century (i.e. atmospheric CO 2 concentration reaching 850 ppm in the year 2100). Potential future changes in distribution and abundance under the IPCC scenario are presented but without taking into account any fishing effort. The simulation showed an improvement in bigeye tuna spawning habitat both in subtropical latitudes and in the eastern tropical Pacific (ETP) where the surface temperature becomes optimal for

  18. Estimating animal behaviour and residency from movement data

    DEFF Research Database (Denmark)

    Pedersen, Martin Wæver; Patterson, Toby Alexander; Thygesen, Uffe Høgsbro

    2011-01-01

    probability distribution of location and behavior at each point in time. With this, the behavioral state of the animal can be associated to regions in space, thus revealing migration corridors and residence areas. We demonstrate the inferential potential of the method by analyzing satellite-linked archival...... tag data from a southern bluefin tuna Thunnus maccoyii where longitudinal coordinates inferred from daylight are supplemented by latitudinal information in recorded sea surface temperatures....

  19. Evolutionary changes of multiple visual pigment genes in the complete genome of Pacific bluefin tuna

    OpenAIRE

    Nakamura, Yoji; Mori, Kazuki; Saitoh, Kenji; Oshima, Kenshiro; Mekuchi, Miyuki; Sugaya, Takuma; Shigenobu, Yuya; Ojima, Nobuhiko; Muta, Shigeru; Fujiwara, Atushi; Yasuike, Motoshige; Oohara, Ichiro; Hirakawa, Hideki; Chowdhury, Vishwajit Sur; Kobayashi, Takanori

    2013-01-01

    Tunas are migratory fishes in offshore habitats and top predators with unique features. Despite their ecological importance and high market values, the open-ocean lifestyle of tuna, in which effective sensing systems such as color vision are required for capture of prey, has been poorly understood. To elucidate the genetic and evolutionary basis of optic adaptation of tuna, we determined the genome sequence of the Pacific bluefin tuna (Thunnus orientalis), using next-generation sequencing tec...

  20. Genome sequence of a diabetes-prone rodent reveals a mutation hotspot around the ParaHox gene cluster

    DEFF Research Database (Denmark)

    Hargreaves, Adam D.; Zhou, Long; Christensen, Josef

    2017-01-01

    The sand rat Psammomys obesus is a gerbil species native to deserts of North Africa and the Middle East, and is constrained in its ecology because high carbohydrate diets induce obesity and type II diabetes that, in extreme cases, can lead to pancreatic failure and death. We report the sequencing...... Pdx1 has been grossly affected by GC-biased mutation, leading to the highest divergence observed for this gene across the Bilateria. In addition to genomic insights into restricted caloric intake in a desert species, the discovery of a localized chromosomal region subject to elevated mutation suggests...

  1. Comparative ecology of widely distributed pelagic fish species in the North Atlantic: Implications for modelling climate and fisheries impacts

    Science.gov (United States)

    Trenkel, V. M.; Huse, G.; MacKenzie, B. R.; Alvarez, P.; Arrizabalaga, H.; Castonguay, M.; Goñi, N.; Grégoire, F.; Hátún, H.; Jansen, T.; Jacobsen, J. A.; Lehodey, P.; Lutcavage, M.; Mariani, P.; Melvin, G. D.; Neilson, J. D.; Nøttestad, L.; Óskarsson, G. J.; Payne, M. R.; Richardson, D. E.; Senina, I.; Speirs, D. C.

    2014-12-01

    This paper reviews the current knowledge on the ecology of widely distributed pelagic fish stocks in the North Atlantic basin with emphasis on their role in the food web and the factors determining their relationship with the environment. We consider herring (Clupea harengus), mackerel (Scomber scombrus), capelin (Mallotus villosus), blue whiting (Micromesistius poutassou), and horse mackerel (Trachurus trachurus), which have distributions extending beyond the continental shelf and predominantly occur on both sides of the North Atlantic. We also include albacore (Thunnus alalunga), bluefin tuna (Thunnus thynnus), swordfish (Xiphias gladius), and blue marlin (Makaira nigricans), which, by contrast, show large-scale migrations at the basin scale. We focus on the links between life history processes and the environment, horizontal and vertical distribution, spatial structure and trophic role. Many of these species carry out extensive migrations from spawning grounds to nursery and feeding areas. Large oceanographic features such as the North Atlantic subpolar gyre play an important role in determining spatial distributions and driving variations in stock size. Given the large biomasses of especially the smaller species considered here, these stocks can exert significant top-down pressures on the food web and are important in supporting higher trophic levels. The review reveals commonalities and differences between the ecology of widely distributed pelagic fish in the NE and NW Atlantic basins, identifies knowledge gaps and modelling needs that the EURO-BASIN project attempts to address.

  2. Massive consumption of gelatinous plankton by Mediterranean apex predators.

    Directory of Open Access Journals (Sweden)

    Luis Cardona

    Full Text Available Stable isotopes of carbon and nitrogen were used to test the hypothesis that stomach content analysis has systematically overlooked the consumption of gelatinous zooplankton by pelagic mesopredators and apex predators. The results strongly supported a major role of gelatinous plankton in the diet of bluefin tuna (Thunnus thynnus, little tunny (Euthynnus alletteratus, spearfish (Tetrapturus belone and swordfish (Xiphias gladius. Loggerhead sea turtles (Caretta caretta in the oceanic stage and ocean sunfish (Mola mola also primarily relied on gelatinous zooplankton. In contrast, stable isotope ratios ruled out any relevant consumption of gelatinous plankton by bluefish (Pomatomus saltatrix, blue shark (Prionace glauca, leerfish (Lichia amia, bonito (Sarda sarda, striped dolphin (Stenella caerueloalba and loggerhead sea turtles (Caretta caretta in the neritic stage, all of which primarily relied on fish and squid. Fin whales (Balaenoptera physalus were confirmed as crustacean consumers. The ratios of stable isotopes in albacore (Thunnus alalunga, amberjack (Seriola dumerili, blue butterfish (Stromaeus fiatola, bullet tuna (Auxis rochei, dolphinfish (Coryphaena hyppurus, horse mackerel (Trachurus trachurus, mackerel (Scomber scombrus and pompano (Trachinotus ovatus were consistent with mixed diets revealed by stomach content analysis, including nekton and crustaceans, but the consumption of gelatinous plankton could not be ruled out completely. In conclusion, the jellyvorous guild in the Mediterranean integrates two specialists (ocean sunfish and loggerhead sea turtles in the oceanic stage and several opportunists (bluefin tuna, little tunny, spearfish, swordfish and, perhaps, blue butterfish, most of them with shrinking populations due to overfishing.

  3. Distribution and abundance of skipjack (Katsuwonus pelamis larvae in eastern Brazilian waters

    Directory of Open Access Journals (Sweden)

    Yasunobu Matsuura

    1982-01-01

    Full Text Available Based on data from two ichthyoplankton surveys carried out off the eastern Brazilian coast in June and November-December 1978, the larval distribution of skipjack is discussed. Skipjack larvae were more abundant in the November-December cruise (southern hemisphere spring. They occurred mainly at stations near the margin of the continental shelf or over seamounts. Out of 240 specimens of scombrid larvae collected in this area, skipjack larvae comprised only 10.4% (25 specimens, whereas the most abundant larvae were Thunnus spp. with 68.8% (165 specimens.

  4. Differential loggerhead by-catch and direct mortality due to surface longlines according to boat strata and gear type

    Directory of Open Access Journals (Sweden)

    Juan A. Camiñas

    2006-12-01

    Full Text Available Surface longline gears are used to fish different species, mainly albacore Thunnus alalunga (Bonnaterre, 1788, bluefin tuna Thunnus thynnus (Linnaeus, 1758, and swordfish Xiphias gladius Linnaeus, 1758, and are considered highly dangerous for threatened marine turtles. Loggerheads Caretta caretta (Linnaeus, 1758 can be incidentally captured by surface longlines. A number of captured individuals die during the fishing operation, which we consider direct mortality due to fishing. We analysed the relative loggerhead by-catch and direct mortality associated with each type of boat and gear from April to December during the period 1999-2004 in the Spanish surface longline fleet that fishes in the western Mediterranean Sea, an important fishing area for this fleet. We used different indices to compute the catch per unit effort (CPUE according to the number of hooks and to the number of fishing operations for each type of boat and gear. Both by-catch and direct mortality differed significantly according to the type of boat and gear. With respect to the number of hooks, boats longer than 12 m not using a roller and targeting bluefin tuna captured the highest number of loggerheads, whereas boats longer than 12 m with a roller that targeted swordfish caused the highest direct mortality. With respect to the number of fishing operations, boats longer than 12 m without a roller that targeted albacore captured the highest number of loggerheads; the highest direct mortality was caused by this type of boat and by boats longer than 12 m using a roller and targeting swordfish.

  5. Epidemiological role of a rodent in Morocco: Case of cutaneous leishmaniasis

    Directory of Open Access Journals (Sweden)

    Mohamed Echchakery

    2015-08-01

    Full Text Available Commensal rodents as well as wild ones may present a potential risk to public health. They are reservoirs or vectors of many pathogens. This review provides an update on their epidemiological role in the spread of leishmaniasis in Morocco. In Morocco, the order Rodentia is represented by 7 families and 32 species of which Rattus norvegicus, Psammomys obesus, Mastomys erythrolecus, Meriones shawi, Meriones crassus and Meriones libycus are considered reservoirs of leishmaniasis in Asia, Midle East and Africa. With the aim to define the extent of zoonotic leishmaniasis risk in Morocco, we represent and discuss the geographical distribution of these potential reservoirs in relation to that of Phlebotomus papatasi, proven vector of cutaneous leishmaniasis by Leishmania major in Morocco.

  6. Improvement of color and physiological properties of tuna-processing by-product by gamma irradiation

    International Nuclear Information System (INIS)

    Choi, Jong-il; Kim, Hyun-Joo; Kim, Jae-Hun; Song, Beom-Seok; Chun, Byeong-Soo; Ahn, Dong-Hyun; Byun, Myung-Woo; Lee, Ju-Woon

    2009-01-01

    Although the by-products from fishery industry had many nutrients, it is being wasted or only used as bacteria media. In this study, the effect of a gamma irradiation on the cooking drips of Thunnus thynnus (CDT) was investigated to examine the possible use of the cooking drips as a functional material for food and cosmetic composition. Total aerobic bacteria, and yeasts/molds from CDT were detected at the level of 2.79 and 2.58 Log CFU/mL, respectively. But, CDT was efficiently sterilized by a gamma irradiation at a low dose of 1 kGy. The Hunter L* value of the gamma-irradiated ethanol extract of CDT was increased, and the a* and b* values were decreased compared to the non-irradiated extract, showing color improvement. Antioxidant activity of the ethanol extract of CDT was increased by a gamma irradiation depending on the irradiation dose. The increased contents of polyphenolic compounds and proteins in CDT extract by gamma irradiation may be the reason of the increased biological activity. These results suggested that the wasted cooking drips can be successfully used as functional components with gamma irradiation treatment.

  7. OBESITY - STRATEGIES FOR THE PREVENTION

    Directory of Open Access Journals (Sweden)

    Alina-Costina LUCA

    2014-12-01

    Full Text Available The last decades there has been characterizes by a worrying rise in obesity among both adults and in children's services. Obesity is considered disease XXI century. Obesity includes a medical field which accumulates a major issue and objective public health in developed countries, a vital prognosis health problem in medical practice and, not least, an aesthetic problem, psychosocial implications. The word comes from the Latin obese, "obesus" = fat, corpulent. Since ancient times, 2,500 years ago, Hippocrates noticed danger overweight "corpulence is not only a disease itself, but is a risk factor." Subsequently, the Indian surgeon Sushruta (VI century BC noted connection between obesity and heart disease. In Europe in medieval and Renaissance, obesity was considered a sign of wealth and prosperity among senior officials.

  8. Trace elements in the kidney tissue of Bluefin Tuna ( Thunnus ...

    African Journals Online (AJOL)

    Trace elements, namely lead (Pb), copper (Cu), manganese (Mn), nickel (Ni), zinc (Zn), and iron (Fe), found in kidney tissues were analyzed and compared between wild/fattened and female/male bluefin tuna (BFT) in the Eastern Mediterranean region of Turkey. One hundred (that is, 50 female and 50 male) individual ...

  9. Dynamic environments of fungus-farming termite mounds exert growth-modulating effects on fungal crop parasites.

    Science.gov (United States)

    Katariya, Lakshya; Ramesh, Priya B; Borges, Renee M

    2018-03-01

    This study investigated for the first time the impact of the internal mound environment of fungus-growing termites on the growth of fungal crop parasites. Mounds of the termite Odontotermes obesus acted as (i) temperature and relative humidity (RH) 'stabilisers' showing dampened daily variation and (ii) 'extreme environments' exhibiting elevated RH and CO 2 levels, compared to the outside. Yet, internal temperatures exhibited seasonal dynamics as did daily and seasonal CO 2 levels. During in situ experiments under termite-excluded conditions within the mound, the growth of the crop parasite Pseudoxylaria was greater inside than outside the mound, i.e., Pseudoxylaria is 'termitariophilic'. Also, ex situ experiments on parasite isolates differing in growth rates and examined under controlled conditions in the absence of termites revealed a variable effect with fungal growth decreasing only under high CO 2 and low temperature conditions, reflecting the in situ parasite growth fluctuations. In essence, the parasite appears to be adapted to survive in the termite mound. Thus the mound microclimate does not inhibit the parasite but the dynamic environmental conditions of the mound affect its growth to varying extents. These results shed light on the impact of animal-engineered structures on parasite ecology, independent of any direct role of animal engineers. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  10. Study on the physiological activities of gamma-irradiated seafood cooking drips

    International Nuclear Information System (INIS)

    Jo, Eu Ri; Kim, Yeon Joo; Choi, Jong Il; Sung, Nak Yun; Jung, Pil Moon; Kim, Jae Hun; Song, Beom Seok; Yoon, Yo Han; Lee, Ju Woon; Lee, Ju Yeoun

    2010-01-01

    Cooking drips which were obtained as by-product after seafood processing in the food industries, still contain lost of proteins, carbohydrates, and other functional materials. This study was conducted to investigate the effect of gamma irradiation on the biological activities of seafood cooking drips. When the cooking drips of Hizikia fusiformis, Enteroctopus dofleini and Thunnus thynnus were irradiated, the antioxidant activities, whitening effect, and angiotensin I converting enzyme inhibition activity of the ethanol extract from seafood cooking drips were all increased by gamma irradiation. This was because of the increased extraction efficiency of available compounds by irradiation. These results suggested that the seafood cooking drips, wasted as by-products, can be used as functional compounds with gamma irradiation treatment

  11. Study on the changes in phyicochemical properties of seafood cooking drips by gamma ray irradiation

    International Nuclear Information System (INIS)

    Choi, Jong Il; Kim, Yeon Joo; Kim, Jae Hun; Yoon, Yo Han; Song, Beom Seok; Lee, Ju Woon; Chun, Byung Soo; Ahn, Dong Hyun; Lee, Ju Yeoun

    2010-01-01

    Cooking drips which were obtained as by-product after seafood processing in the food industries, still contain lots of proteins, carbohydrates, and other functional materials. But, the seafood cooking drips are easily contaminated because of its rich nutrients, and their color are very dark. This study was conducted to investigate the effect of gamma irradiation on the quality of seafood cooking drips including Hizikia fusiformis, Enteroctopus dofleini, and Thunnus thynnus. The Hunter's color values (L, Brightness) of H. fusiformis, and T.thynnus, were increased with increasing irradiation doses, showing becoming bright. The crude protein content and crude lipid content were increased by gamma irradiation. These results indicated that gamma irradiation increased extraction efficiency of available compounds in cooking drips

  12. Study on the physiological activities of gamma-irradiated seafood cooking drips

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Eu Ri; Kim, Yeon Joo; Choi, Jong Il; Sung, Nak Yun; Jung, Pil Moon; Kim, Jae Hun; Song, Beom Seok; Yoon, Yo Han; Lee, Ju Woon [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Lee, Ju Yeoun [Chonbuk National University, Jeonju (Korea, Republic of)

    2010-03-15

    Cooking drips which were obtained as by-product after seafood processing in the food industries, still contain lost of proteins, carbohydrates, and other functional materials. This study was conducted to investigate the effect of gamma irradiation on the biological activities of seafood cooking drips. When the cooking drips of Hizikia fusiformis, Enteroctopus dofleini and Thunnus thynnus were irradiated, the antioxidant activities, whitening effect, and angiotensin I converting enzyme inhibition activity of the ethanol extract from seafood cooking drips were all increased by gamma irradiation. This was because of the increased extraction efficiency of available compounds by irradiation. These results suggested that the seafood cooking drips, wasted as by-products, can be used as functional compounds with gamma irradiation treatment.

  13. Low-E Retrofit Demonstration and Educational Program

    Energy Technology Data Exchange (ETDEWEB)

    Culp, Thomas D [Birch Point Consulting LLC; Wiehagen, Joseph [Home Innovation Research Labs, Inc.; Drumheller, S Craig [Home Innovation Research Labs, Inc.; Siegel, John [Quanta Technologies Inc.; Stratmoen, Todd [Larson Manufacturing

    2013-11-16

    The objective of this project was to demonstrate the capability of low-emissivity (low-E) storm windows / panels and low-E retrofit glazing systems to significantly and cost effectively improve the energy efficiency of both existing residential and commercial buildings. The key outcomes are listed below: RESIDENTIAL CASE STUDIES: (a) A residential case study in two large multifamily apartment buildings in Philadelphia showed a substantial 18-22% reduction in heating energy use and a 9% reduction in cooling energy use by replacing old clear glass storm windows with modern low-E storm windows. Furthermore, the new low-E storm windows reduced the overall apartment air leakage by an average of 10%. (b) Air leakage testing on interior low-E panels installed in a New York City multifamily building over windows with and without AC units showed that the effective leakage area of the windows was reduced by 77-95%. (c) To study the use of low-E storm windows in a warmer mixed climate with a balance of both heating and cooling, 10 older homes near Atlanta with single pane windows were tested with three types of exterior storm windows: clear glass, low-E glass with high solar heat gain, and low-E glass with lower solar heat gain. The storm windows significantly reduced the overall home air leakage by an average of 17%, or 3.7 ACH50. Considerably high variability in the data made it difficult to draw strong conclusions about the overall energy usage, but for heating periods, the low-E storm windows showed approximately 15% heating energy savings, whereas clear storm windows were neutral in performance. For cooling periods, the low-E storm windows showed a wide range of performance from 2% to over 30% cooling energy savings. Overall, the study showed the potential for significantly more energy savings from using low-E glass versus no storm window or clear glass storm windows in warmer mixed climates, but it is difficult to conclusively say whether one type of low-E performed

  14. Efecto de actividades turísticas sobre el comportamiento de fauna representativa de las Islas Galápagos, Ecuador Short-term effects of tourism activities on the behavior of representative fauna on the Galapagos Islands, Ecuador

    Directory of Open Access Journals (Sweden)

    Fernanda González-Pérez

    2010-01-01

    Full Text Available Fueron consideradas clave para actividades turísticas en 16 sitios de las Islas Galápagos: la raya sartén marmoleada (Taeniura meyeri, raya águila (Aetobatus narinari, tiburón de aleta blanca (Triaenodon obesus, tortuga verde (Chelonia mydas, cormorán no volador (Phalacrocorax harrisi y lobo marino de Galápagos (Zalophus califórnianus, con el objetivo de analizar reacciones a corto plazo ante actividades de buceo apnea o "snorkeling", buceo autónomo o "scuba", paseos en bote o "panga-ride" y caminatas. Para cada especie se documentó su comportamiento al momento del encuentro con los turistas y su reacción ante dicha situación. El uso del Análisis de Correspondencias reveló que el tipo de reacción de las especies depende significativamente de la actividad turística, a excepción de las rayas sartén marmoleada y águila. Asimismo, los análisis indican que, a nivel de especie, cada actividad turística estuvo asociada significativamente con reacciones animales particulares. Esto sugiere que las especies analizadas son sensibles ante determinadas actividades turísticas, por lo que se deberían implementar recomendaciones de manejo a fin de garantizar la sustentabilidad del ecoturismo.This study focused on the short-term reactions of six key species (Taeniura meyeri, Aetobatus narinari, Triaendon obesus, Chelonia mydas, Phalacrocorax harrisi, and Zalophus califórnianus during tourism activities (SCUBA diving, panga-ride, snorkeling, and hiking at 16 tourist sites on the islands. For each species we recorded its behavior when first encountering tourists and its reaction following this encounter. A Correspondence Analysis revealed that the type of reaction of the species depended significantly on the type of touristic activity, with the exception of the black spotted and eagle rays. Moreover, the analysis showed that, for each species, the different tourist activities were significantly associated with particular animal activities

  15. Building mud castles: a perspective from brick-laying termites.

    Science.gov (United States)

    Zachariah, Nikita; Das, Aritra; Murthy, Tejas G; Borges, Renee M

    2017-07-05

    Animal constructions such as termite mounds have received scrutiny by architects, structural engineers, soil scientists and behavioural ecologists but their basic building blocks remain uncharacterized and the criteria used for material selection unexplored. By conducting controlled experiments on Odontotermes obesus termites, we characterize the building blocks of termite mounds and determine the key elements defining material choice and usage by these accomplished engineers. Using biocement and a self-organized process, termites fabricate, transport and assemble spherical unitary structures called boluses that have a bimodal size distribution, achieving an optimal packing solution for mound construction. Granular, hydrophilic, osmotically inactive, non-hygroscopic materials with surface roughness, rigidity and containing organic matter are the easiest to handle and are crucial determinants of mass transfer during mound construction. We suggest that these properties, along with optimal moisture availability, are important predictors of the global geographic distribution of termites.

  16. Modelling retention and dispersion mechanisms of bluefin tuna eggs and larvae in the Northwest Mediterranean Sea

    DEFF Research Database (Denmark)

    Mariani, Patrizio; MacKenzie, Brian; Iudicone, D.

    2010-01-01

    Knowledge of early life history of most fish species in the Mediterranean Sea is sparse and processes affecting their recruitment are poorly understood. This is particularly true for bluefin tuna, Thunnus thynnus, even though this species is one of the world's most valued fish species. Here we...... develop, apply and validate an individually based coupled biological-physical oceanographic model of fish early life history in the Mediterranean Sea. We first validate the general structure of the coupled model with a 12-day Lagrangian drift study of anchovy (Engraulis encrasicolus) larvae in the Catalan...... mesoscale processes in the Balearic area and thus potentially affect bluefin tuna larvae. These modelling approaches can increase understanding of bluefin tuna recruitment processes and eventually contribute to management of bluefin tuna fisheries....

  17. Low Voltage Low Light Imager and Photodetector

    Science.gov (United States)

    Nikzad, Shouleh (Inventor); Martin, Chris (Inventor); Hoenk, Michael E. (Inventor)

    2013-01-01

    Highly efficient, low energy, low light level imagers and photodetectors are provided. In particular, a novel class of Della-Doped Electron Bombarded Array (DDEBA) photodetectors that will reduce the size, mass, power, complexity, and cost of conventional imaging systems while improving performance by using a thinned imager that is capable of detecting low-energy electrons, has high gain, and is of low noise.

  18. Low Vision

    Science.gov (United States)

    ... USAJobs Home » Statistics and Data » Low Vision Listen Low Vision Low Vision Defined: Low Vision is defined as the best- ... Ethnicity 2010 U.S. Age-Specific Prevalence Rates for Low Vision by Age, and Race/Ethnicity Table for 2010 ...

  19. Low-cost, highly transparent flexible low-e coating film to enable electrochromic windows with increased energy savings

    Energy Technology Data Exchange (ETDEWEB)

    Berland, Brian [ITN Energy Systems, Inc., Littleton, CO (United States); Hollingsworth, Russell [ITN Energy Systems, Inc., Littleton, CO (United States)

    2015-03-31

    Five Quads of energy are lost through windows annually in the U.S. Low-e coatings are increasingly employed to reduce the wasted energy. Most commonly, the low-e coating is an oxide material applied directly to the glass at high temperature. With over 100,000,000 existing homes, a retrofit product is crucial to achieve widespread energy savings. Low-e films, i.e. coatings on polymeric substrates, are now also available to meet this need. However, the traditional oxide materials and process is incompatible with low temperature plastics. Alternate high performing low-e films typically incorporate materials that limit visible transmission to 35% or less. Further, the cost is high. The objective of this award was to develop a retrofit, integrated low-e/electrochromic window film to dramatically reduce energy lost through windows. While field testing of state-of-the-art electrochromic (EC) windows show the energy savings are maximized if a low-e coating is used in conjunction with the EC, available low-e films have a low visible transmission (~70% or less) that limits the achievable clear state and therefore, appearance and energy savings potential. Comprehensive energy savings models were completed at Lawrence Berkeley National Lab (LBNL). A parametric approach was used to project energy usage for windows with a large range of low-e properties across all U.S. climate zones, without limiting the study to materials that had already been produced commercially or made in a lab. The model enables projection of energy savings for low-e films as well as integrated low-e/EC products. This project developed a novel low-e film, optimized for compatibility with EC windows, using low temperature, high deposition rate processes for the growth of low-e coatings on plastic films by microwave plasma enhanced chemical vapor deposition. Silica films with good density and optical properties were demonstrated at deposition rates as high as 130Å/sec. A simple bi-layer low-e stack of

  20. Aquatic Coleoptera from El Cristal Natural Reserve (Santa Fe Province, Argentina

    Directory of Open Access Journals (Sweden)

    Gabriel A. MACCHIA

    2015-01-01

    Full Text Available Se presenta una lista de los coleópteros acuáticos colectados en la Reserva Natural El Cristal. Se identificaron 77 especies incluidas en 35 géneros y seis familias. Diez géneros se citan por primera vez de la provincia de Santa Fe: Copelatus Erichson, Anodocheilus Babington, Bidessodes Régimbart, Bidessonotus Régimbart, Pachydrus Sharp, Laccomimus Toledo & Michat (Dytiscidae, Mesonoterus Sharp (Noteridae, Pelonomus Erichson (Dryopidae, Chaetarthria Stephens y Paracymus Thomson (Hydrophilidae. Además, 17 especies se registran por primera vez de la provincia de Santa Fe: Thermonectus succinctus (Aubé, Anodocheilus maculatus Babington, Bidessonotus obtusatus Régimbart, Pachydrus globosus (Aubé, P. obesus Sharp (Dytiscidae, Hydrocanthus paraguayensis Zimmermann, Mesonoterus laevicollis Sharp, Suphis freudei Mouchamps, Suphisellus curtus (Sharp, S. grammicus (Sharp, S. nigrinus (Aubé, S. remator (Sharp (Noteridae, Chaetarthria bruchi Balfour-Browne, Enochrus sublongus (Fall, Berosus paraguayanus Knisch, Derallus altus (Leconte y Phaenonotum regimbarti Bruch (Hydrophilidae.

  1. Displacement effects of heavy human use on coral reef predators within the Molokini Marine Life Conservation District.

    Science.gov (United States)

    Filous, Alexander; Friedlander, Alan M; Koike, Haruko; Lammers, Marc; Wong, Adam; Stone, Kristy; Sparks, Russell T

    2017-08-15

    The impact of marine ecotourism on reef predators is poorly understood and there is growing concern that overcrowding in Marine Protected Areas (MPAs) may disturb the species that these areas were established to protect. To improve our understanding of this issue, we used acoustic telemetry to examine the relationship between human activity at the Molokini Marine Life Conservation District (MLCD) and the habitat use of five reef-associated predators (Caranx melampygus, Caranx ignobilis, Triaenodon obesus, Carcharhinus amblyrhynchos, and Aprion virscens). During peak hours of human use, there was a negative relationship (R 2 =0.77, P<0.001) between the presence of bluefin trevally (Caranx melampygus) and vessels in subzone A. No other species showed strong evidence of this relationship. However, our results suggest that during this time, the natural ecosystem function that the reserve was established to protect may be compromised and overcrowding should be considered when managing MPAs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Responses of epithelial cells to low and very low doses of low let radiation

    International Nuclear Information System (INIS)

    Mothersill, Carmel; Seymour, Colin

    2003-01-01

    Recent advances in our knowledge of the biological effects of low doses of ionizing radiation have shown unexpected phenomena. These vary in the endpoint used to detect them and in the dose range examined but all occur as high-frequency events in cell populations. They include: 1. a 'bystander effect' which can be demonstrated at low doses as a transferable.factor(s) causing radiobiological effects in unexposed cells, 2. an assortment of delayed effects' occurring in progeny of cells exposed to low doses, 3. Low-dose Hypersensitivity (HRS) and Increased radioresistance (IRR) which can collectively be demonstrated as a change in the dose-effect relationship, occurring around 0.5-1 Gy of low LET radiation and 4. adaptive responses where cells exposed to very low doses followed by higher doses, exhibit an induced relatively resistant response to the second dose. In all cases, the effect of very low doses is greater than would be predicted by extrapolation of high dose data and is inconsistent with conventional DNA break/repair-based radiobiology. In practical risk assessment terms, the relative importance of the effects are high at low doses where they dominate the response, and small at high doses. This paper reviews these assorted phenomena and in particular seeks to explore whether related or distinct mechanisms underlie these various effects Understanding the mechanistic basis of these phenomena may suggest new approaches to controlling death or survival sectoring at low radiation doses. The key question is whether these low dose phenomena necessitate a new approach to risk assessment. (author)

  3. Mercury levels of yellowfin tuna (Thunnus albacares) are associated with capture location.

    Science.gov (United States)

    Nicklisch, Sascha C T; Bonito, Lindsay T; Sandin, Stuart; Hamdoun, Amro

    2017-10-01

    Mercury is a toxic compound to which humans are exposed by consumption of fish. Current fish consumption advisories focus on minimizing the risk posed by the species that are most likely to have high levels of mercury. Less accounted for is the variation within species, and the potential role of the geographic origin of a fish in determining its mercury level. Here we surveyed the mercury levels in 117 yellowfin tuna caught from 12 different locations worldwide. Our results indicated significant variation in yellowfin tuna methylmercury load, with levels that ranged from 0.03 to 0.82 μg/g wet weight across individual fish. Mean mercury levels were only weakly associated with fish size (R 2  mercury load, and argue for better traceability of fish to improve the accuracy of exposure risk predictions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Residency and spatial use by reef sharks of an isolated seamount and its implications for conservation.

    Science.gov (United States)

    Barnett, Adam; Abrantes, Kátya G; Seymour, Jamie; Fitzpatrick, Richard

    2012-01-01

    Although marine protected areas (MPAs) are a common conservation strategy, these areas are often designed with little prior knowledge of the spatial behaviour of the species they are designed to protect. Currently, the Coral Sea area and its seamounts (north-east Australia) are under review to determine if MPAs are warranted. The protection of sharks at these seamounts should be an integral component of conservation plans. Therefore, knowledge on the spatial ecology of sharks at the Coral Sea seamounts is essential for the appropriate implementation of management and conservation plans. Acoustic telemetry was used to determine residency, site fidelity and spatial use of three shark species at Osprey Reef: whitetip reef sharks Triaenodon obesus, grey reef sharks Carcharhinus amblyrhynchos and silvertip sharks Carcharhinus albimarginatus. Most individuals showed year round residency at Osprey Reef, although five of the 49 individuals tagged moved to the neighbouring Shark Reef (~14 km away) and one grey reef shark completed a round trip of ~250 km to the Great Barrier Reef. Additionally, individuals of white tip and grey reef sharks showed strong site fidelity to the areas they were tagged, and there was low spatial overlap between groups of sharks tagged at different locations. Spatial use at Osprey Reef by adult sharks is generally restricted to the north-west corner. The high residency and limited spatial use of Osprey Reef suggests that reef sharks would be highly vulnerable to targeted fishing pressure and that MPAs incorporating no-take of sharks would be effective in protecting reef shark populations at Osprey and Shark Reef.

  5. Residency and spatial use by reef sharks of an isolated seamount and its implications for conservation.

    Directory of Open Access Journals (Sweden)

    Adam Barnett

    Full Text Available Although marine protected areas (MPAs are a common conservation strategy, these areas are often designed with little prior knowledge of the spatial behaviour of the species they are designed to protect. Currently, the Coral Sea area and its seamounts (north-east Australia are under review to determine if MPAs are warranted. The protection of sharks at these seamounts should be an integral component of conservation plans. Therefore, knowledge on the spatial ecology of sharks at the Coral Sea seamounts is essential for the appropriate implementation of management and conservation plans. Acoustic telemetry was used to determine residency, site fidelity and spatial use of three shark species at Osprey Reef: whitetip reef sharks Triaenodon obesus, grey reef sharks Carcharhinus amblyrhynchos and silvertip sharks Carcharhinus albimarginatus. Most individuals showed year round residency at Osprey Reef, although five of the 49 individuals tagged moved to the neighbouring Shark Reef (~14 km away and one grey reef shark completed a round trip of ~250 km to the Great Barrier Reef. Additionally, individuals of white tip and grey reef sharks showed strong site fidelity to the areas they were tagged, and there was low spatial overlap between groups of sharks tagged at different locations. Spatial use at Osprey Reef by adult sharks is generally restricted to the north-west corner. The high residency and limited spatial use of Osprey Reef suggests that reef sharks would be highly vulnerable to targeted fishing pressure and that MPAs incorporating no-take of sharks would be effective in protecting reef shark populations at Osprey and Shark Reef.

  6. Residency and Spatial Use by Reef Sharks of an Isolated Seamount and Its Implications for Conservation

    Science.gov (United States)

    Barnett, Adam; Abrantes, Kátya G.; Seymour, Jamie; Fitzpatrick, Richard

    2012-01-01

    Although marine protected areas (MPAs) are a common conservation strategy, these areas are often designed with little prior knowledge of the spatial behaviour of the species they are designed to protect. Currently, the Coral Sea area and its seamounts (north-east Australia) are under review to determine if MPAs are warranted. The protection of sharks at these seamounts should be an integral component of conservation plans. Therefore, knowledge on the spatial ecology of sharks at the Coral Sea seamounts is essential for the appropriate implementation of management and conservation plans. Acoustic telemetry was used to determine residency, site fidelity and spatial use of three shark species at Osprey Reef: whitetip reef sharks Triaenodon obesus, grey reef sharks Carcharhinus amblyrhynchos and silvertip sharks Carcharhinus albimarginatus. Most individuals showed year round residency at Osprey Reef, although five of the 49 individuals tagged moved to the neighbouring Shark Reef (∼14 km away) and one grey reef shark completed a round trip of ∼250 km to the Great Barrier Reef. Additionally, individuals of white tip and grey reef sharks showed strong site fidelity to the areas they were tagged, and there was low spatial overlap between groups of sharks tagged at different locations. Spatial use at Osprey Reef by adult sharks is generally restricted to the north-west corner. The high residency and limited spatial use of Osprey Reef suggests that reef sharks would be highly vulnerable to targeted fishing pressure and that MPAs incorporating no-take of sharks would be effective in protecting reef shark populations at Osprey and Shark Reef. PMID:22615782

  7. Encoded low swing for ultra low power interconnect

    NARCIS (Netherlands)

    Krishnan, R.; Pineda de Gyvez, J.

    2003-01-01

    We present a novel encoded-low swing technique for ultra low power interconnect. Using this technique and an efficient circuit implementation, we achieve an average of 45.7% improvement in the power-delay product over the schemes utilizing low swing techniques alone, for random bit streams. Also, we

  8. Low Power/Low Voltage Interface Circuitry for Capacitive Sensors

    DEFF Research Database (Denmark)

    Furst, Claus Efdmann

    This thesis focuses mainly on low power/low voltage interface circuits, implemented in CMOS, for capacitive sensors. A brief discussion of demands and possibilities for analog signal processing in the future is presented. Techniques for low power design is presented. This is done by analyzing power...... power consumption. It is shown that the Sigma-Delta modulator is advantageous when embedded in a feedback loop with a mechanical sensor. Here a micro mechanical capacitive microphone. Feedback and detection circuitry for a capacitive microphone is presented. Practical implementations of low power....../low voltage interface circuitry is presented. It is demonstrated that an amplifier optimized for a capacitive microphone implemented in a standard 0.7 micron CMOS technology competes well with a traditional JFET amplifier. Furthermore a low power/low voltage 3rd order Sigma-Delta modulator is presented...

  9. Relationships between tuna catch and variable frequency oceanographic conditions

    Directory of Open Access Journals (Sweden)

    F. I. Ormaza-González

    2016-08-01

    Full Text Available Skipjack (Katsuwunus pelamis, yellow fin (Thunnus albacares and albacore (Thunnus alulunga tunas landed in the Eastern Pacific Ocean (EPO countries and Ecuador were correlated to the Indexes Oceanic El Niño (ONI and Multivariate Enso Index (MEI. The temporal series 1983–2012, and 1977–1999 (warm Pacific Decadal Oscillation, PDO, and 2000–2012 (cold PDO were analyzed. Linear correlation showed that at least 11 % of the total landings were associated with the MEI, with a slightly negative gradient from cold to warm conditions. When non-linear regression (n  =  6, the R2 was higher up to 0.304 (MEI, r =  0.551. The correlation shows high spread from −0.5 to +0.5 for both MEI/ONI; the highest landings occurred at 0.34–0.45; both indexes suggested that at extreme values < −1.0 and > 1.1 total landings tend to decrease. Landings were associated up to 21.9 % (MEI in 2000–2012, 1983–1999 rendered lower R2 (< 0.09; i.e., during cold PDO periods there was a higher association between landings and oceanographic conditions. For the non-linear regression (n  =  6 a R2 of 0.374 (MEI and 0.408 (ONI were registered, for the 2000–2012, a higher R2 was observed in 1983–1999, 0.443 and 0.711 for MEI and ONI respectively, suggesting that is better to analyze split series (1983–1999, 2000–2012 than as a whole (1983–2012, due to noise produced by the transition from hot to cold PDOs. The highest landings were in the range −0.2 to 0.5 for MEI/ONI. The linear regression of skipjack landings in Ecuador gave an R2 of 0.140 (MEI and 0.066 (ONI and the non-linear were 0.440 and 0.183 respectively. Total landings in the EPO associated to oceanographic events of high and low frequencies could be used somehow as predictors of the high El Niño o La Niña. There is a clear evidence that tuna fish biomass are at higher levels when the PDO is on cold phase (2000–2030 and vice versa on warm phase (1980–1999. The

  10. Low Vision FAQs

    Science.gov (United States)

    ... de los Ojos Cómo hablarle a su oculista Low Vision FAQs What is low vision? Low vision is a visual impairment, not correctable ... person’s ability to perform everyday activities. What causes low vision? Low vision can result from a variety of ...

  11. Low back pain and low level flying

    NARCIS (Netherlands)

    J.C.F.M. Aghina

    1989-01-01

    textabstractLow level flying is a very good tactical possibility to carry out a mission unseen by a hostile radarsystem. Nowadays, Western Europe in general and the Federal Republic of Germany in particular, decreased . the permissions to low level flying in assigned regions. That's why the

  12. Low-e Storm Windows: Market Assessment and Pathways to Market Transformation

    Energy Technology Data Exchange (ETDEWEB)

    Cort, Katherine A.

    2013-06-08

    Field studies sponsored by the U.S. Department of Energy (DOE) have shown that the use of low-e storm windows can lead to significant heating and cooling energy savings in residential homes. This study examines the market for low-e storm windows based on market data, case studies, and recent experience with weatherization deployment programs. It uses information from interviews conducted with DOE researchers and industry partners involved in case studies and early deployment efforts related to low-e storm windows. In addition, this study examines potential barriers to market acceptance, assesses the market and energy savings potential, and identifies opportunities to transform the market for low-e storm windows and overcome market adoption barriers.

  13. Low doses effects and gamma radiations low dose rates

    International Nuclear Information System (INIS)

    Averbeck, D.

    1999-01-01

    This expose wishes for bringing some definitions and base facts relative to the problematics of low doses effects and low dose rates effects. It shows some already used methods and some actual experimental approaches by focusing on the effects of ionizing radiations with a low linear energy transfer. (N.C.)

  14. Low Bone Density

    Science.gov (United States)

    ... Density Exam/Testing › Low Bone Density Low Bone Density Low bone density is when your bone density ... people with normal bone density. Detecting Low Bone Density A bone density test will determine whether you ...

  15. Understanding low-level radioactive waste. National Low-Level Radioactive Waste Management Program

    International Nuclear Information System (INIS)

    1983-10-01

    Chapters are devoted to: background and policymaking for low-level waste management; commercial low-level waste generation; Department of Energy low-level waste generation; low-level waste treatment; packaging and transportation; commercial low-level waste disposal; Department of Energy low-level waste disposal; Department of Energy low-level waste management program; and laws and regulations

  16. Busting the myth of low motivation in low-skilled workers

    DEFF Research Database (Denmark)

    Mariager-Anderson, Kristina; Cort, Pia

    2016-01-01

    Should low-skilled workers continuously adapt to the needs of the labour market to ensure their own employability? The preoccupation with low-skilled people and their reluctance to be lifelong learners is apparent in surveys and research projects attempting to identify low-skilled workers’ barrie...... to learning: Are low-skilled workers unable to do what is right according to policies? Should they continuously adapt to the needs of the labour market and ensure their own employability? This policy narrative of ‘unmotivated’ low-skilled workers needs to be questioned....

  17. Pediatric Low Vision

    Science.gov (United States)

    ... Asked Questions Español Condiciones Chinese Conditions Pediatric Low Vision What is Low Vision? Partial vision loss that cannot be corrected causes ... and play. What are the signs of Low Vision? Some signs of low vision include difficulty recognizing ...

  18. Long-term low-calorie low-protein vegan diet and endurance exercise are associated with low cardiometabolic risk.

    Science.gov (United States)

    Fontana, Luigi; Meyer, Timothy E; Klein, Samuel; Holloszy, John O

    2007-06-01

    Western diets, which typically contain large amounts of energy-dense processed foods, together with a sedentary lifestyle are associated with increased cardiometabolic risk. We evaluated the long-term effects of consuming a low-calorie low-protein vegan diet or performing regular endurance exercise on cardiometabolic risk factors. In this cross-sectional study, cardiometabolic risk factors were evaluated in 21 sedentary subjects, who had been on a low-calorie low-protein raw vegan diet for 4.4 +/- 2.8 years, (mean age, 53.1 +/- 11 yrs), 21 body mass index (BMI)-matched endurance runners consuming Western diets, and 21 age- and gender-matched sedentary subjects, consuming Western diets. BMI was lower in the low-calorie low-protein vegan diet (21.3 +/- 3.1 kg/m(2)) and endurance runner (21.1 +/- 1.6 kg/m(2)) groups than in the sedentary Western diet group (26.5 +/- 2.7 kg/m(2)) (p vegan diet and runner groups than in the Western diet group (all p vegan diet group (104 +/- 15 and 62 +/- 11 mm Hg) than in BMI-matched endurance runners (122 +/- 13 and 72 +/- 9 mmHg) and Western diet group (132 +/- 14 and 79 +/- 8 mm Hg) (p vegan diet or regular endurance exercise training is associated with low cardiometabolic risk. Moreover, our data suggest that specific components of a low-calorie low-protein vegan diet provide additional beneficial effects on blood pressure.

  19. Low-E Storm Windows Gain Acceptance as a Home Weatherization Measure

    Energy Technology Data Exchange (ETDEWEB)

    Gilbride, Theresa L.; Cort, Katherine A.

    2016-05-16

    This article for Home Energy Magazine describes work by the U.S. Department of Energy to develop low-emissivity storm windows as an energy efficiency-retrofit option for existing homes. The article describes the low-emissivity invisible silver metal coatings on the glass, which reflect heat back into the home in winter or back outside in summer and the benefits of low-e storm windows including insulation, air sealing, noise blocking, protection of antique windows, etc. The article also describes Pacific Northwest National Laboratory's efforts on behalf of DOE to overcome market barriers to adoption of the technology, including performance validation studies in the PNNL Lab Homes, cost effectiveness analysis, production of reports, brochures, how-to guides on low-e storm window installation for the Building America Solution Center, and a video posted on YouTube. PNNL's efforts were reviewed by the Pacific Northwest Regional Technical Forum (RTF), which serves as the advisory board to the Pacific Northwest Electric Power Planning Council and Bonneville Power Administration. In late July 2015, the RTF approved the low-e storm window measure’s savings and specifications, a critical step in integrating low-e storm windows into energy-efficiency planning and utility weatherization and incentive programs. PNNL estimates that more than 90 million homes in the United States with single-pane or low-performing double-pane windows would benefit from the technology. Low-e storm windows are suitable not only for private residences but also for small commercial buildings, historic properties, and facilities that house residents, such as nursing homes, dormitories, and in-patient facilities. To further assist in the market transformation of low-e storm windows and other high-efficiency window attachments, DOE helped found the window Attachment Energy Rating Council (AERC) in 2015. AERC is an independent, public interest, non-profit organization whose mission is to rate

  20. Low profile, low cost, new geometry integrated inductors

    DEFF Research Database (Denmark)

    Ouyang, Ziwei; Thomsen, Ole Cornelius; Andersen, Michael A. E.

    2011-01-01

    windings with well-defined thickness. Many advantages and disadvantages are described in depth. In this work, inverse coupling and direct coupling in the new geometry integrated inductors have been analyzed. Coupling characteristic caused by a special saturation behavior has been emphasis. And also...... variable inductors caused by the special saturation behavior may be utilized in some applications. The new integrated inductors make it possible to build low-profile, low-cost, flexibility DC/DC converters, and it can be extensively designed for the low-voltage and high-current required by the modern...

  1. A new gnathiid (Crustacea: Isopoda) parasitizing two species of requiem sharks from Lizard Island, Great Barrier Reef, Australia.

    Science.gov (United States)

    Coetzee, Maryke L; Smit, Nico J; Grutter, Alexandra S; Davies, Angela J

    2008-06-01

    Third-stage juveniles (praniza 3) of Gnathia grandilaris n. sp. were collected from the gill filaments and septa of 5 requiem sharks, including a white tip reef shark, Triaenodon obesus, and 4 grey reef sharks, Carcharhinus amblyrhynchos, at Lizard Island, Great Barrier Reef, Australia, in March 2002. Some juvenile gnathiids were then maintained in fresh sea water until they molted to adults. Adult males appeared 19 days following detachment of juveniles from host fishes, but no juveniles molted successfully into females. The current description is based, therefore, on bright field and scanning electron microscopy observations of adult males and third-stage juveniles. Unique features of the male include the triangular-shaped inferior medio-frontal process, 2 areolae on the dorsal surface of the pylopod, and a slender pleotelson (twice as long as wide) with lateral concavities. The third-stage juvenile has distinctive white pigmentation on the black pereon when alive, while the mandible has 9 triangular backwardly directed teeth. This species has the largest male and third-stage juvenile of any Gnathia spp. from Australia and of any gnathiid isopods associated with elasmobranchs.

  2. Diurnal respiration of a termite mound

    Science.gov (United States)

    King, Hunter; Ocko, Samuel; Mahadevan, L.

    2014-11-01

    Many species of fungus-harvesting termites build largely empty, massive mound structures which protrude from the ground above their subterranean nests. It has been long proposed that the function of these mounds is to facilitate exchange of heat, humidity, and respiratory gases; this would give the colony a controlled climate in which to raise fungus and brood. However, the specific mechanism by which the mound achieves ventilation has remained a topic of debate, as direct measurement of internal air flows has remained difficult. By directly measuring these elusive, tiny flows with a custom sensor, we find that the mound architecture of the species Odontotermes obesus takes advantage of daily oscillations in ambient temperature to drive convection and gas transport. This contradicts previous theories, which point to internal metabolic heating and external wind as driving forces. Our result, a novel example of deriving useful work from a fluctuating scalar parameter, should contribute to better understanding insect swarm construction and possible development in passive human architecture, both of which have been spurred by previous research on termites. We acknowledge support from HFSP.

  3. Low and very low doses, new recommendations?

    International Nuclear Information System (INIS)

    Foucher, N.

    1999-01-01

    The topic of the seminar organized by the world council of nuclear workers (WONUC) was the effects of low or very low doses on human health. Discussions centred round the linearity of the relation between dose and effect in the evaluation and management of the health hazard. The recommendations proposed by ICPR (international commission for radiological protection) are based on this linearity as a precaution. On the one hand it is remembered that low dose irradiation might be beneficial. It has been proved that the irradiation of the whole body is efficient in case of Hodgkin lymphoma. On the other hand it is remembered that doses as low as 10 mSv in utero have led to an excess of cancer in children. Studies based on experimentally radio-induced cancers have been carried out in Japan, China, Canada and France.Their results seem to be not consistent with the hypothesis of linearity. During the last decade a lot of work has been made but a conclusion is far to be reached, it is said that the American department of energy (DOE) has invited bids in 1999 to launch research programs in order to clarify the situation. (A.C.)

  4. Low fasting low high-density lipoprotein and postprandial lipemia

    Directory of Open Access Journals (Sweden)

    Sorodila Konstandina

    2004-07-01

    Full Text Available Abstract Background Low levels of high density lipoprotein (HDL cholesterol and disturbed postprandial lipemia are associated with coronary heart disease. In the present study, we evaluated the variation of triglyceride (TG postprandially in respect to serum HDL cholesterol levels. Results Fifty two Greek men were divided into 2 main groups: a the low HDL group (HDL p = 0.002. The low HDL group had significantly higher TG at 4, 6 and 8 h postprandially compared to the controls (p = 0.006, p = 0.002, and p p = 0.017 compared to the matched-control group. ROC analysis showed that fasting TG ≥ 121 mg/dl have 100% sensitivity and 81% specificity for an abnormal TG response (auc = 0.962, p Conclusions The delayed TG clearance postprandially seems to result in low HDL cholesterol even in subjects with low fasting TG. The fasting TG > 121 mg/dl are predictable for abnormal response to fatty meal.

  5. Low Cost, Low Power, High Sensitivity Magnetometer

    Science.gov (United States)

    2008-12-01

    which are used to measure the small magnetic signals from brain. Other types of vector magnetometers are fluxgate , coil based, and magnetoresistance...concentrator with the magnetometer currently used in Army multimodal sensor systems, the Brown fluxgate . One sees the MEMS fluxgate magnetometer is...Guedes, A.; et al., 2008: Hybrid - LOW COST, LOW POWER, HIGH SENSITIVITY MAGNETOMETER A.S. Edelstein*, James E. Burnette, Greg A. Fischer, M.G

  6. Building America's Low-e Storm Window Adoption Program Plan (FY2014)

    Energy Technology Data Exchange (ETDEWEB)

    Cort, Katherine A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2013-12-23

    Low emissivity (low-e) storm windows/panels appear to hold promise for effectively reducing existing home heating, ventilation, and air-conditioning (HVAC) consumption. Due to the affordability of low-e storm windows and the large numbers of existing homes that have low-performing single-pane or double-pane clear windows, a tremendous opportunity exists to provide energy savings by transforming the low-e storm window market and increasing market adoption. This report outlines U.S. Department of Energy (DOE) Building America’s planned market transformation activities in support of low-e storm window adoption during fiscal year (FY) 2014.

  7. Low resistance, low-inductance power connectors

    Science.gov (United States)

    Coteus, Paul W.; Ferencz, Andrew; Hall, Shawn Anthony; Takken, Todd Edward

    2018-01-16

    An electrical connector includes an anode assembly for conducting an electrical supply current from a source to a destination, the anode assembly includes an anode formed into a first shape from sheet metal or other sheet-like conducting material. A cathode assembly conducts an electrical return current from the destination to the source, the cathode assembly includes a cathode formed into a second shape from sheet metal or other sheet-like conducting material. An insulator prevents electrical conduction between the anode and the cathode. The first and second shapes are such as to provide a conformity of one to the other, with the insulator therebetween having a predetermined relatively thin thickness. A predetermined low-resistance path for the supply current is provided by the anode, a predetermined low-resistance path for the return current is provided by the cathode, and the proximity of the anode to the cathode along these paths provides a predetermined low self-inductance of the connector, where the proximity is afforded by the conformity of the first and second shapes.

  8. Low Blood Pressure

    Science.gov (United States)

    ... a problem. Sometimes blood pressure that is too low can also cause problems. Blood pressure is the ... reading is 90/60 or lower, you have low blood pressure. Some people have low blood pressure ...

  9. Low-fiber diet

    Science.gov (United States)

    ... residue; Low-fiber diet; Fiber restricted diet; Crohn disease - low fiber diet; Ulcerative colitis - low fiber diet; ... them if they do not contain seeds or pulp: Yellow squash (without seeds) Spinach Pumpkin Eggplant Potatoes, ...

  10. Low Potassium (Hypokalemia)

    Science.gov (United States)

    Symptoms Low potassium (hypokalemia) By Mayo Clinic Staff Low potassium (hypokalemia) refers to a lower than normal potassium level ... 2 millimoles per liter (mmol/L). A very low potassium level (less than 2.5 mmol/L) ...

  11. Biological influence from low dose and low-dose rate radiation

    International Nuclear Information System (INIS)

    Magae, Junji

    2007-01-01

    Although living organisms have defense mechanisms for radioadaptive response, the influence is considered to vary qualitatively and quantitatively for low dose and high dose, as well as for low-dose rate and high-dose rate. This article describes the bioresponse to low dose and low-dose rate. Among various biomolecules, DNA is the most sensitive to radiation, and accurate replication of DNA is an essential requirement for the survival of living organisms. Also, the influence of active enzymes resulted from the effect of radiation on enzymes in the body is larger than the direct influence of radiation on the body. After this, the article describes the carcinogenic risk by low-dose radiation, and then so-called Hormesis effect to create cancer inhibition effect by stimulating active physiology. (S.K.)

  12. Low Blood Pressure (Hypotension)

    Science.gov (United States)

    ... lowest at night and rises sharply on waking. Blood pressure: How low can you go? What's considered low ... low blood pressure. Medications that can cause low blood pressure Some medications can cause low blood pressure, including: ...

  13. THz Tube Waveguides With Low Loss, Low Dispersion, and High Bandwidth

    DEFF Research Database (Denmark)

    Bao, Hualong; Nielsen, Kristian; Bang, Ole

    2014-01-01

    We propose, model and experimentally characterize a novel class of terahertz hollow-core tube waveguides with high-loss cladding material, resulting in propagation with low loss, low dispersion, and high useful bandwidth.......We propose, model and experimentally characterize a novel class of terahertz hollow-core tube waveguides with high-loss cladding material, resulting in propagation with low loss, low dispersion, and high useful bandwidth....

  14. Housing conditions as a social determinant of low birthweight and preterm low birthweight

    Directory of Open Access Journals (Sweden)

    Mario Vianna Vettore

    2010-12-01

    Full Text Available OBJECTIVE: To assess the relationship between housing conditions and low birthweight and preterm low birthweight among low-income women. METHODS: A case-control study was conducted with post-partum women living in the city of Rio de Janeiro, Southeast Brazil, in 2003-2005. Two groups of cases, low birthweight (n=96 and preterm low birthweight infants (n=68, were compared against normal weight term controls (n=393. Housing conditions were categorized into three levels: adequate, inadequate, and highly inadequate. Covariates included sociodemographic and anthropometric characteristics, risk behaviors, violence, anxiety, satisfaction during pregnancy, obstetric history and prenatal care. RESULTS: Poor housing conditions was independently associated with low birthweight (inadequate - OR 2.3 [1.1;4.6]; highly inadequate - OR 7.6 [2.1;27.6] and preterm low birthweight (inadequate - OR 2.2 [1.1;4.3]; highly inadequate - OR 7.6 [2.4;23.9] and factors associated with outcomes were inadequate prenatal care and previous preterm birth. Low income and low maternal body mass index remained associated with low birthweight. CONCLUSIONS: Poor housing conditions were associated with low birthweight and preterm low birthweight.

  15. Clean utilization of low-rank coals for low-cost power generation

    International Nuclear Information System (INIS)

    Sondreal, E.A.

    1992-01-01

    Despite the unique utilization problems of low-rank coals, the ten US steam electric plants having the lowest operating cost in 1990 were all fueled on either lignite or subbituminous coal. Ash deposition problems, which have been a major barrier to sustaining high load on US boilers burning high-sodium low-rank coals, have been substantially reduced by improvements in coal selection, boiler design, on-line cleaning, operating conditions, and additives. Advantages of low-rank coals in advanced systems are their noncaking behavior when heated, their high reactivity allowing more complete reaction at lower temperatures, and the low sulfur content of selected deposits. The principal barrier issues are the high-temperature behavior of ash and volatile alkali derived from the coal-bound sodium found in some low-rank coals. Successful upgrading of low-rank coals requires that the product be both stable and suitable for end use in conventional and advanced systems. Coal-water fuel produced by hydrothermal processing of high-moisture low-rank coal meets these criteria, whereas most dry products from drying or carbonizing in hot gas tend to create dust and spontaneous ignition problems unless coated, agglomerated, briquetted, or afforded special handling

  16. Low back pain

    DEFF Research Database (Denmark)

    Buchbinder, Rachelle; van Tulder, Maurits; Öberg, Birgitta

    2018-01-01

    Low back pain is the leading worldwide cause of years lost to disability and its burden is growing alongside the increasing and ageing population.1 Because these population shifts are more rapid in low-income and middle-income countries, where adequate resources to address the problem might...... not exist, the effects will probably be more extreme in these regions. Most low back pain is unrelated to specific identifiable spinal abnormalities, and our Viewpoint, the third paper in this Lancet Series,2,3 is a call for action on this global problem of low back pain....

  17. The low changing the atomic low and the low about taxation duty of 12 March 2004

    International Nuclear Information System (INIS)

    Kwasniewski, A.

    2004-01-01

    The low changes and considerably complements the atomic low of 29 November 2000 (Dz. U. no 3, 2001), especially in the scope of nuclear medicine, radiation protection, safeguard and nuclear materials management as well as interventional activity in case of radiation accidents

  18. Dimethylether: a low velocity, low diffusion drift chamber gas

    International Nuclear Information System (INIS)

    Villa, F.

    1983-01-01

    There are two main motivations to look for a low electron mobility gas: the first is that a low drift velocity relaxes the need to measure drift times with nanosecond (or even subnanosecond) precision; the second is that (in an ideal drift geometry), the capability of resolving two closely spaced tracks depends upon the ratio of electron mobility to ion mobility μ/sub e//μ/sub i/. Since μ/sub i/ is rather constant, the way to separate two tracks is to slow down the electrons. Many other properties are required besides low mobility and low drifting electron temperature: the gas should have a large (> 10 3 ) stable gain; it must be chemically stable and not oxic; it should not attack materials commonly used to fabricate drift chambers, etc. With these requirements in mind, we have tried a few promising (on paper) gases, either pure or in admixture with Argon. One of the gases examined, dimethylether [(CH 3 ) 2 )], has shown interesting characteristics

  19. Low Testosterone

    DEFF Research Database (Denmark)

    Holmboe, Stine Agergaard; Jensen, Tina Kold; Linneberg, Allan René

    2016-01-01

    Context: Low serum T levels have been associated with type 2 diabetes (T2D) and cardiovascular disease. However, it is unresolved whether low T is a risk factor or rather a risk marker for these conditions. Objective: The objective of the study was to investigate serum levels of total T, SHBG, fr...

  20. Fad diets and obesity--Part IV: Low-carbohydrate vs. low-fat diets.

    Science.gov (United States)

    Moyad, Mark A

    2005-02-01

    The first three parts of this series of articles covered the basics of some of the more popular low-carbohydrate diets, and the theories behind them. In the fourth and final part of this series, some of the more popular low-fat and low-calorie diets, such as the Ornish diet and Weight Watchers, are covered briefly. Recently, several clinical trials of longer duration that compared low-carbohydrate versus low-fat diets have been published. These studies demonstrate that some of the low-carbohydrate diets result in reduced weight in the short-term, but their ability to reduce weight long-term any better than low-fat or other diets has been questioned. Most popular or fad diets have some positive messages contained within them and some preliminary positive short-term results, but overall the compliance rates with any fad diet are very poor over the long-term. The decision to go on any diet should be made with a health professional who can monitor the patient closely.

  1. Weight loss with a low-carbohydrate, Mediterranean, or low-fat diet.

    Science.gov (United States)

    Shai, Iris; Schwarzfuchs, Dan; Henkin, Yaakov; Shahar, Danit R; Witkow, Shula; Greenberg, Ilana; Golan, Rachel; Fraser, Drora; Bolotin, Arkady; Vardi, Hilel; Tangi-Rozental, Osnat; Zuk-Ramot, Rachel; Sarusi, Benjamin; Brickner, Dov; Schwartz, Ziva; Sheiner, Einat; Marko, Rachel; Katorza, Esther; Thiery, Joachim; Fiedler, Georg Martin; Blüher, Matthias; Stumvoll, Michael; Stampfer, Meir J

    2008-07-17

    Trials comparing the effectiveness and safety of weight-loss diets are frequently limited by short follow-up times and high dropout rates. In this 2-year trial, we randomly assigned 322 moderately obese subjects (mean age, 52 years; mean body-mass index [the weight in kilograms divided by the square of the height in meters], 31; male sex, 86%) to one of three diets: low-fat, restricted-calorie; Mediterranean, restricted-calorie; or low-carbohydrate, non-restricted-calorie. The rate of adherence to a study diet was 95.4% at 1 year and 84.6% at 2 years. The Mediterranean-diet group consumed the largest amounts of dietary fiber and had the highest ratio of monounsaturated to saturated fat (Pcarbohydrate group consumed the smallest amount of carbohydrates and the largest amounts of fat, protein, and cholesterol and had the highest percentage of participants with detectable urinary ketones (Ploss was 2.9 kg for the low-fat group, 4.4 kg for the Mediterranean-diet group, and 4.7 kg for the low-carbohydrate group (Plosses were 3.3 kg, 4.6 kg, and 5.5 kg, respectively. The relative reduction in the ratio of total cholesterol to high-density lipoprotein cholesterol was 20% in the low-carbohydrate group and 12% in the low-fat group (P=0.01). Among the 36 subjects with diabetes, changes in fasting plasma glucose and insulin levels were more favorable among those assigned to the Mediterranean diet than among those assigned to the low-fat diet (Pcarbohydrate diets may be effective alternatives to low-fat diets. The more favorable effects on lipids (with the low-carbohydrate diet) and on glycemic control (with the Mediterranean diet) suggest that personal preferences and metabolic considerations might inform individualized tailoring of dietary interventions. (ClinicalTrials.gov number, NCT00160108.) 2008 Massachusetts Medical Society

  2. Low temperature oxidation and spontaneous combustion characteristics of upgraded low rank coal

    Energy Technology Data Exchange (ETDEWEB)

    Choi, H.K.; Kim, S.D.; Yoo, J.H.; Chun, D.H.; Rhim, Y.J.; Lee, S.H. [Korea Institute of Energy Research, Daejeon (Korea, Republic of)

    2013-07-01

    The low temperature oxidation and spontaneous combustion characteristics of dried coal produced from low rank coal using the upgraded brown coal (UBC) process were investigated. To this end, proximate properties, crossing-point temperature (CPT), and isothermal oxidation characteristics of the coal were analyzed. The isothermal oxidation characteristics were estimated by considering the formation rates of CO and CO{sub 2} at low temperatures. The upgraded low rank coal had higher heating values than the raw coal. It also had less susceptibility to low temperature oxidation and spontaneous combustion. This seemed to result from the coating of the asphalt on the surface of the coal, which suppressed the active functional groups from reacting with oxygen in the air. The increasing upgrading pressure negatively affected the low temperature oxidation and spontaneous combustion.

  3. Low Cost/Low Noise Variable Pitch Ducted Fan, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — ACI proposes a design for a Propulsor (Low Cost/Low Noise Variable Pitch Ducted Fan) that has wide application in all sectors of Aviation. Propulsor hardware of this...

  4. LOW FREQUENCY DAMPER

    Directory of Open Access Journals (Sweden)

    Radu BOGATEANU

    2009-09-01

    Full Text Available The low frequency damper is an autonomous equipment for damping vibrations with the 1-20Hz range.Its autonomy enables the equipment to be located in various mechanical systems, without requiring special hydraulic installations.The low frequency damper was designed for damping the low frequency oscillations occurring in the circuit controls of the upgraded IAR-99 Aircraft.The low frequency damper is a novelty in the aerospace field ,with applicability in several areas as it can be built up in an appropriate range of dimensions meeting the requirements of different beneficiaries. On this line an equipment able to damp an extended frequency range was performed for damping oscillations in the pipes of the nuclear power plants.This damper, tested in INCAS laboratories matched the requirements of the beneficiary.The low frequency damper is patented – the patent no. 114583C1/2000 is held by INCAS.

  5. Low Offset AC Correlator.

    Science.gov (United States)

    This patent describes a low offset AC correlator avoids DC offset and low frequency noise by frequency operating the correlation signal so that low...noise, low level AC amplification can be substituted for DC amplification. Subsequently, the high level AC signal is demodulated to a DC level. (Author)

  6. System transient analysis code development for low pressure and low power

    International Nuclear Information System (INIS)

    Kim, Hee Cheol

    1998-02-01

    A real time reactor system analysis code, ARTIST, based on drift flux model has been developed to investigate the transient system behavior under low pressure, low flow and low power conditions with noncondensable gas present in the system. The governing equations of the ARTIST code consist of three mass continuity equations (steam, liquid and noncondensable), two energy equations (gas and mixture) and one momentum equation (mixture) constituted with the drift flux model. The capability of ARTIST in predicting two-phase flow void distribution in the system has been validated against experimental data. The results of the ARTIST axial void distribution at low pressure and low flow, are far better than the results of both the homogeneous model of TASS code and the two-fluid model of RELAP5/MOD3 code. Also, RELAP5/MOD3 calculation shows the large amplitude of void fraction oscillations at low pressure. These results imply that interfacial momentum transfer terms in the two-fluid model formulation should be carefully constituted, especially for the low pressure condition due to the big density differences between steam and water. Thermal-hydraulic state solution scheme is developed when noncondensable gas exists. Numerical consistency and convergence of obtaining equilibrium state is tested with the ideal problems for various situations including very low partial pressure conditions. Calculated thermal-hydraulic state for each test shows consistent and expected behaviour. A new multi-layer back propagation network algorithm for calculating the departure from nucleate boiling ratio (DNBR) is developed and adopted in ARTIST code in order to have real-time DNBR evaluation by eliminating the tandem procedure of the transient DNBR calculation. The algorithm trained by different patterns generated by latin hypercube sampling method on the performance space is tested for the randomly sampled untrained data and the transient DNBR data. The uncertainty of the algorithm is

  7. Systematic review of randomized controlled trials of low-carbohydrate vs. low-fat/low-calorie diets in the management of obesity and its comorbidities.

    Science.gov (United States)

    Hession, M; Rolland, C; Kulkarni, U; Wise, A; Broom, J

    2009-01-01

    There are few studies comparing the effects of low-carbohydrate/high-protein diets with low-fat/high-carbohydrate diets for obesity and cardiovascular disease risk. This systematic review focuses on randomized controlled trials of low-carbohydrate diets compared with low-fat/low-calorie diets. Studies conducted in adult populations with mean or median body mass index of > or =28 kg m(-2) were included. Thirteen electronic databases were searched and randomized controlled trials from January 2000 to March 2007 were evaluated. Trials were included if they lasted at least 6 months and assessed the weight-loss effects of low-carbohydrate diets against low-fat/low-calorie diets. For each study, data were abstracted and checked by two researchers prior to electronic data entry. The computer program Review Manager 4.2.2 was used for the data analysis. Thirteen articles met the inclusion criteria. There were significant differences between the groups for weight, high-density lipoprotein cholesterol, triacylglycerols and systolic blood pressure, favouring the low-carbohydrate diet. There was a higher attrition rate in the low-fat compared with the low-carbohydrate groups suggesting a patient preference for a low-carbohydrate/high-protein approach as opposed to the Public Health preference of a low-fat/high-carbohydrate diet. Evidence from this systematic review demonstrates that low-carbohydrate/high-protein diets are more effective at 6 months and are as effective, if not more, as low-fat diets in reducing weight and cardiovascular disease risk up to 1 year. More evidence and longer-term studies are needed to assess the long-term cardiovascular benefits from the weight loss achieved using these diets.

  8. Multifunctional Lattices with Low Thermal Expansion and Low Thermal Conductivity

    Science.gov (United States)

    Xu, Hang; Liu, Lu; Pasini, Damiano

    Systems in space are vulnerable to large temperature changes when travelling into and out of the Earth's shadow. Variations in temperature can lead to undesired geometric changes in susceptible applications requiring very fine precision. In addition, temperature-sensitive electronic equipment hosted in a satellite needs adequate thermal-control to guarantee a moderate ambient temperature. To address these specifications, materials with low coefficient of thermal expansion (CTE) and low coefficient of thermal conductivity (CTC) over a wide range of temperatures are often sought, especially for bearing components in satellites. Besides low CTE and low CTC, these materials should also provide desirable stiffness, strength and extraordinarily low mass. This work presents ultralightweight bi-material lattices with tunable CTE and CTC, besides high stiffness and strength. We show that the compensation of the thermal expansion and joint rotation at the lattice joints can be used as an effective strategy to tailor thermomechanical performance. Proof-of-concept lattices are fabricated from Al and Ti alloy sheets via a simple snap-fit technique and vacuum brazing, and their CTE and CTC are assessed via a combination of experiments and theory. Corresponding Author.

  9. Low-rank coal research

    Energy Technology Data Exchange (ETDEWEB)

    Weber, G. F.; Laudal, D. L.

    1989-01-01

    This work is a compilation of reports on ongoing research at the University of North Dakota. Topics include: Control Technology and Coal Preparation Research (SO{sub x}/NO{sub x} control, waste management), Advanced Research and Technology Development (turbine combustion phenomena, combustion inorganic transformation, coal/char reactivity, liquefaction reactivity of low-rank coals, gasification ash and slag characterization, fine particulate emissions), Combustion Research (fluidized bed combustion, beneficiation of low-rank coals, combustion characterization of low-rank coal fuels, diesel utilization of low-rank coals), Liquefaction Research (low-rank coal direct liquefaction), and Gasification Research (hydrogen production from low-rank coals, advanced wastewater treatment, mild gasification, color and residual COD removal from Synfuel wastewaters, Great Plains Gasification Plant, gasifier optimization).

  10. Low energy intense electron beams with extra-low energy spread

    International Nuclear Information System (INIS)

    Aleksandrov, A.V.; Calabrese, R.; Ciullo, G.; Dikansky, N.S.; Guidi, V.; Kot, N.C.; Kudelainen, V.I.; Lamanna, G.; Lebedev, V.A.; Logachov, P.V.; Tecchio, L.; Yang, B.

    1994-01-01

    Maximum achievable intensity for low energy electron beams is a feature that is not very often compatible with low energy spread. We show that a proper choice of the source and the acceleration optics allows one to match them together. In this scheme, a GaAs photocathode excited by a single-mode infrared laser and adiabatic acceleration in fully magnetised optics enables the production of a low-energy-spread electron beam with relatively high intensity. The technological problems associated with the method are discussed together with its limitations. (orig.)

  11. Morphological, nutritional and safety traits of bluefin tuna (Thunnus thynnus reared in floating cages

    Directory of Open Access Journals (Sweden)

    B. M. Poli

    2010-04-01

    Full Text Available To evaluate the influence of fattening on morphological, nutritional and safety characteristics, two lots of bluefin tuna were sampled before (November: 2 C, 4 ? and after 5 months of fattening (April: 5 C, 5 ?. The specimens, after death, were refrigerated and analysed at different times over the period of a week for morphological and flesh physico-chemical parameters in six muscle sites. Tuna sampled in April had greater body weight (44.04 vs 36.41kg, trunk length (52.21 vs 48.22cm and minimum and maximum circumferences (13.74 vs 12.77 and 94.90 vs 89.10cm. No differences in other linear measures or body components were found. Fattening did not influence flesh colour or total lipid content, producing small differences in its chemical composition: greater C18:0, C18:1n9 and PUFAn6 percentages; higher putrescine and histamine (0.489 vs 0.335 and 0.666 vs 0.370mg/kg but lower spermine and spermidine (10.598 vs 17.387 and 2.420 vs 3.928mg/kg levels. Large differences in physico-chemical parameters were found between muscle sites and a significant interaction between sampling date and muscle site indicated non homogeneous changes in chemical composition of dorsal, ventral and red muscle after fattening. Sex only influenced fat content in viscera (C 12.84 vs ? 9.84%.

  12. Histamine formation and the freshness of yellowfin tuna (Thunnus albacares stored at different temperatures

    Directory of Open Access Journals (Sweden)

    B.K.K.K. Jinadasa

    2015-12-01

    Full Text Available This study was conducted to investigate the effect of storage temperatures on the shelf life of yellowfin tuna (YFT loins by studying of microbial, chemical and organoleptic changes. Shelf life of YFT was determined through changes in total aerobic bacterial plate counts (APC, total volatile basic nitrogen (TVB-N trimethylamine (TMA, organoleptic properties and histamine development during storage at 0, 4 and 7°C. Based on TVB-N value indices, YFT maintained an acceptable shelf life for 21, 17 and 12 days at 0, 4 and 7°C, respectively. Nevertheless, YFT was rejected earlier by the sensory panellists than their TVB-N value indicated. Histamine development was found to be lower than the European Union safety level for 100 mg/kg fish during storage at 0 and 7°C for 21 and 17 days, respectively. Aerobic bacteria initially dominated the micro-flora on YFT; however, as storage time increased, aerobic bacteria became dominant at cold storage, but the numbers exceeded the International Commission on Microbiological Specifications for Foods (ICMSF limit of 107 cfu/g in storage at 7°C after 17 days. Therefore, it can be concluded that the storage of fresh YFT in below 4°C has good enough to the shelf life of products (two weeks.

  13. Low-level waste management

    International Nuclear Information System (INIS)

    Levin, G.B.

    1980-01-01

    An overview of the current situation in the United States and a look to the future of low-level waste management are presented. Current problems and challenges are discussed, such as: the need of additional disposal sites in the future; risks and costs involved in transport of low-level wastes; reduction of low-level waste volume through smelting, incineration, and storage for wastes containing nuclides with short half lives; development of a national policy for the management of low-level waste, and its implementation through a sensible system of regulations. Establishing a success with low-level waste management should provide the momentum and public confidence needed to continue on and to resolve the technical and politically more difficult low-level waste problems

  14. Low-level Radioactive waste Management

    International Nuclear Information System (INIS)

    1991-01-01

    This meeting describes low-level radioactive waste management problems and contains 8 papers: 1 Low-level radioactive waste management: exemption concept and criteria used by international organizations. 2 Low-level radioactive waste management: french and foreign regulations 3 Low-level radioactive waste management in EDF nuclear power plants (FRANCE) 4 Low-level radioactive waste management in COGEMA (FRANCE) 5 Importance of low-level radioactive wastes in dismantling strategy in CEA (FRANCE) 6 Low-level radioactive waste management in hospitals 7 Low-level radioactive waste disposal: radiation protection laws 8 Methods of low-level radioactive materials measurements during reactor dismantling or nuclear facilities demolition (FRANCE)

  15. Low-level radioactive waste, mixed low-level radioactive waste, and biomedical mixed waste

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    This document describes the proceedings of a workshop entitled: Low-Level Radioactive Waste, Mixed Low-Level Radioactive Waste, and Biomedical Mixed Waste presented by the National Low-Level Waste Management Program at the University of Florida, October 17-19, 1994. The topics covered during the workshop include technical data and practical information regarding the generation, handling, storage and disposal of low-level radioactive and mixed wastes. A description of low-level radioactive waste activities in the United States and the regional compacts is presented

  16. The Majorana Low-noise Low-background Front-end Electronics

    Science.gov (United States)

    Abgrall, N.; Aguayo, E.; Avignone, F. T.; Barabash, A. S.; Bertrand, F. E.; Boswell, M.; Brudanin, V.; Busch, M.; Byram, D.; Caldwell, A. S.; Chan, Y.-D.; Christofferson, C. D.; Combs, D. C.; Cuesta, C.; Detwiler, J. A.; Doe, P. J.; Efremenko, Yu.; Egorov, V.; Ejiri, H.; Elliott, S. R.; Fast, J. E.; Finnerty, P.; Fraenkle, F. M.; Galindo-Uribarri, A.; Giovanetti, G. K.; Goett, J.; Green, M. P.; Gruszko, J.; Guiseppe, V. E.; Gusev, K.; Hallin, A. L.; Hazama, R.; Hegai, A.; Henning, R.; Hoppe, E. W.; Howard, S.; Howe, M. A.; Keeter, K. J.; Kidd, M. F.; Kochetov, O.; Konovalov, S. I.; Kouzes, R. T.; LaFerriere, B. D.; Leon, J.; Leviner, L. E.; Loach, J. C.; MacMullin, J.; MacMullin, S.; Martin, R. D.; Meijer, S.; Mertens, S.; Nomachi, M.; Orrell, J. L.; O'Shaughnessy, C.; Overman, N. R.; Phillips, D. G.; Poon, A. W. P.; Pushkin, K.; Radford, D. C.; Rager, J.; Rielage, K.; Robertson, R. G. H.; Romero-Romero, E.; Ronquest, M. C.; Schubert, A. G.; Shanks, B.; Shima, T.; Shirchenko, M.; Snavely, K. J.; Snyder, N.; Suriano, A. M.; Thompson, J.; Timkin, V.; Tornow, W.; Trimble, J. E.; Varner, R. L.; Vasilyev, S.; Vetter, K.; Vorren, K.; White, B. R.; Wilkerson, J. F.; Wiseman, C.; Xu, W.; Yakushev, E.; Young, A. R.; Yu, C.-H.; Yumatov, V.

    The MAJORANA DEMONSTRATOR will search for the neutrinoless double beta decay (ββ(0ν)) of the isotope 76Ge with a mixed array of enriched and natural germanium detectors. In view of the next generation of tonne-scale germanium-based ββ(0ν)-decay searches, a major goal of the MAJORANA DEMONSTRATOR is to demonstrate a path forward to achieving a background rate at or below 1 cnt/(ROI-t-y) in the 4 keV region of interest (ROI) around the 2039-keV Q-value of the 76Ge ββ(0ν)-decay. Such a requirement on the background level significantly constrains the design of the readout electronics, which is further driven by noise and energy resolution performances. We present here the low-noise low- background front-end electronics developed for the low-capacitance p-type point contact (P-PC) germanium detectors of the MAJORANA DEMONSTRATOR. This resistive-feedback front-end, specifically designed to have low mass, is fabricated on a radioassayed fused-silica substrate where the feedback resistor consists of a sputtered thin film of high purity amorphous germanium and the feedback capacitor is based on the capacitance between gold conductive traces.

  17. Direct quantification of energy intake in an apex marine predator suggests physiology is a key driver of migrations.

    Science.gov (United States)

    Whitlock, Rebecca E; Hazen, Elliott L; Walli, Andreas; Farwell, Charles; Bograd, Steven J; Foley, David G; Castleton, Michael; Block, Barbara A

    2015-09-01

    Pacific bluefin tuna (Thunnus orientalis) are highly migratory apex marine predators that inhabit a broad thermal niche. The energy needed for migration must be garnered by foraging, but measuring energy intake in the marine environment is challenging. We quantified the energy intake of Pacific bluefin tuna in the California Current using a laboratory-validated model, the first such measurement in a wild marine predator. Mean daily energy intake was highest off the coast of Baja California, Mexico in summer (mean ± SD, 1034 ± 669 kcal), followed by autumn when Pacific bluefin achieve their northernmost range in waters off northern California (944 ± 579 kcal). Movements were not always consistent with maximizing energy intake: the Pacific bluefin move out of energy rich waters both in late summer and winter, coincident with rising and falling water temperatures, respectively. We hypothesize that temperature-related physiological constraints drive migration and that Pacific bluefin tuna optimize energy intake within a range of optimal aerobic performance.

  18. The imprint of anthropogenic CO2 emissions on Atlantic bluefin tuna otoliths

    Science.gov (United States)

    Fraile, Igaratza; Arrizabalaga, Haritz; Groeneveld, Jeroen; Kölling, Martin; Santos, Miguel Neves; Macías, David; Addis, Piero; Dettman, David L.; Karakulak, Saadet; Deguara, Simeon; Rooker, Jay R.

    2016-06-01

    Otoliths of Atlantic bluefin tuna (Thunnus thynnus) collected from the Mediterranean Sea and North Atlantic Ocean were analyzed to evaluate changes in the seawater isotopic composition over time. We report an annual otolith δ13C record that documents the magnitude of the δ13C depletion in the Mediterranean Sea between 1989 and 2010. Atlantic bluefin tuna in our sample (n = 632) ranged from 1 to 22 years, and otolith material corresponding to the first year of life (back-calculated birth year) was used to reconstruct seawater isotopic composition. Otolith δ18O remained relatively stable between 1989 and 2010, whereas a statistically significant decrease in δ13C was detected across the time interval investigated, with a rate of decline of 0.05‰ yr- 1 (- 0.94‰ depletion throughout the recorded period). The depletion in otolith δ13C over time was associated with the oceanic uptake of anthropogenically derived CO2.

  19. Genotoxicological safety of the ethanol extract from seafood cooking drips by gamma irradiation

    International Nuclear Information System (INIS)

    Kim, Hyun Joo; Choi, Jong Il; Lee, Hee Sub; Kim, Jae Hun; Byun, Myung Woo; Chun, Byung Soo; Ahn, Dong Hyun; Yook, Hong Sun; Kim, Kee Hyuk

    2008-01-01

    Although seafood cooking drips were the byproducts from the fishery industry it was known that the cooking drips had many nutrients and could be used as functional materials. Previously, the physiological properties of cooking drips were shown to be increased by a gamma irradiation. But, there was no report on the safe for the genotoxicity on the irradiation. In this study, the genotoxicity of the cooking drips from Hizikia fusiformis, Enteroctopus dofleni and Thunnus thynnus was evaluated by the Ames test (Salmonella typhimurium reversion assay) and the SOS chromotest. The results from all samples were negative in the bacterial reversion assay with S. typhimurium TA98, TA100. No mutagenicity was detected in the assay, both with and without metabolic activation. The SOS chromotest also indicated that the gamma-irradiated seafood cooking drips did not show any mutagenicity. Therefore, this study indicated that gamma irradiation could be used for the hygiene, functional properties and processibility of seafood cooking drips

  20. A reconstructed database of historic bluefin tuna captures in the Gibraltar Strait and Western Mediterranean

    Directory of Open Access Journals (Sweden)

    Josué M. Polanco-Martínez

    2018-02-01

    Full Text Available This data paper presents a reconstruction of a compilation of a small but consistent database of historical capture records of bluefin tuna (Thunnus thynnus; BFT hereafter from the Gibraltar Strait and Western Mediterranean (Portugal, Spain and Italy. The compilation come from diverse historical and documentary sources and span the time interval from 1525 to 1936 covering a period of 412 years. There is a total of 3074 datum, which reach up to 67.83% of the total implying a 32.17% of missing data. However, we have only reconstructed the captures for the time interval 1700–1936 and we provide these reconstructions only for this time interval and for 9 out of 11 series due to the scarcity and inhomogeneity of the two oldest capture time series. This reconstructed database provides an invaluable opportunity for fisheries and marine research as well as for multidisciplinary research in climate change. Keywords: Data reconstructions, DINEOF, Missing data, Historic Bluefin tuna captures, Gibraltar Strait and Western Mediterranean

  1. Algunas adiciones a la fauna monogenética (Plathyhelminthes de Venezuela | Some additions to venezuelan monogenetic fauna (Plathyhelminthes

    Directory of Open Access Journals (Sweden)

    Arnaldo Figueredo Rodríguez

    2017-11-01

    Full Text Available As part of periodical studies about parasitic fauna of marine fishes carried out in Laboratory of Parasitology of Universidad de Oriente, campus Nueva Esparta, several commercially important ichthyic species were evaluated. Fishes were collected in three landing ports of Nueva Esparta state and immediately processed. Gills were carefully extracted and reviewed under stereoscopic microscope. Permanent slides were prepared with parasites found, and then to obtain descriptive images. In all cases, the parasitic habitat was gills of hosts. New records for Venezuela comprises five monogeneans: Capsala manteri collected on little tunny, Euthynnus alleteratus; Capsala pricei found over lesser devil ray, Mobula hypostoma; Tristoma integrum observed on swordfish, Xiphias gladius; Decacotyle floridana registred over spotted eagle ray, Aetobatus narinari and Hexostoma lintoni discovered on yellowfin tuna, Thunnus albacares. For the first time for the country, representatives of sub-families Capsalinae and Decacotylinae were referred to. Some details of parasites anatomy are described, discussing about taxonomic and biogeographic aspects.

  2. Low Vision Tips

    Science.gov (United States)

    ... this page: https://medlineplus.gov/lowvision.html MedlinePlus: Low Vision Tips We are sorry. MedlinePlus no longer maintains the For Low Vision Users page. You will still find health resources ...

  3. Low-charge-state linac

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K.W.; Kim, J.W.

    1995-08-01

    A design is being developed for a low-charge-state linac suitable for injecting ATLAS with a low-charge-state, radioactive beam. Initial work indicates that the existing ATLAS interdigital superconducting accelerating structures, together with the superconducting quadrupole transverse focussing element discussed above, provides a basis for a high-performance low-charge-state linac. The initial 2 or 3 MV of such a linac could be based on a normally-conducting, low-frequency RFQ, possibly combined with 24-MHz superconducting interdigital structures. Beam dynamics studies of the whole low-charge-state post-accelerator section were carried out in early FY 1995.

  4. Low fitness is associated with abdominal adiposity and low-grade inflammation independent of BMI

    DEFF Research Database (Denmark)

    Wedell-Neergaard, Anne-Sophie; Eriksen, Louise; Grønbæk, Morten

    2018-01-01

    OBJECTIVE: Up to 30% of obese individuals are metabolically healthy. Metabolically healthy obese (MHO) individuals are characterized by having low abdominal adiposity, low inflammation level and low risk of developing metabolic comorbidity. In this study, we hypothesize that cardiorespiratory fit...... to be inversely associated with both abdominal adiposity and low-grade inflammation independent of BMI. These data suggest that, in spite of BMI, high fitness levels lead to a reduction in abdominal fat mass and low-grade inflammation.......OBJECTIVE: Up to 30% of obese individuals are metabolically healthy. Metabolically healthy obese (MHO) individuals are characterized by having low abdominal adiposity, low inflammation level and low risk of developing metabolic comorbidity. In this study, we hypothesize that cardiorespiratory...... fitness (fitness) is a determinant factor for the MHO individuals and aim to investigate the associations between fitness, abdominal adiposity and low-grade inflammation within different BMI categories. METHOD: Data from 10,976 individuals from the general population, DANHES 2007-2008, on waist...

  5. Low blood sugar

    Science.gov (United States)

    ... a medical emergency. It can cause seizures and brain damage. Severe low blood sugar that causes you to become unconscious is called hypoglycemic or insulin shock. Even one episode of severe low blood ...

  6. Low-mass stars with mass loss and low-luminosity carbon star formation

    International Nuclear Information System (INIS)

    Boothroyd, A.I.

    1987-01-01

    The effects of large carbon enrichments in static stellar envelopes were investigated, using new Los Alamos opacities (including low-temperature carbon and molecular opacities) and including carbon ionizations. To search for the production of low-mass,low-luminosity carbon stars, detailed stellar evolutionary computations were carried out for a grid of low-mass stars of two different metallicities. The stars were evolved from the main sequence through all intermediate stages and through helium-shell flashes on the asymptotic giant branch. The effects of the latest nuclear reaction rates, the new Los Alamos opacities, Reimers-type wind mass loss, and detailed treatment of convection and semi-convection were investigated. Two low-luminosity carbon stars were achieved, in excellent agreement with observations. Conditions favoring dredge-up (and thus carbon-star production) include a reasonably large convective mixing length, low metallicity, relatively large envelope mass, and high flash strength. Mass loss was of major importance, tending to oppose dredge-up; the total mass-loss amounts inferred from observations suffice to prevent formation of high-mass, high-luminosity carbon stars

  7. Energy Savings of Low-E Storm Windows and Panels across US Climate Zones

    Energy Technology Data Exchange (ETDEWEB)

    Culp, Thomas D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cort, Katherine A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-10-01

    This report builds off of previous modeling work related to low-e storm windows used to create a "Database of U.S. Climate-Based Analysis for Low-E Storm Windows." This work updates similar studies using new fuel costs and examining the separate contributions of reduced air leakage and reduced coefficients of overall heat transfer and solar heat gain. In this report we examine the energy savings and cost effectiveness of low-E storm windows in residential homes across a broad range of U.S. climates, excluding the impact from infiltration reductions, which tend to vary using the National Energy Audit Tool (NEAT) and RESFEN model calculations. This report includes a summary of the results, NEAT and RESFEN background, methodology, and input assumptions, and an appendix with detailed results and assumptions by climate zone.

  8. A low-power multi port register file design using a low-swing strategy

    International Nuclear Information System (INIS)

    Yan Hao; Liu Yan; Hua Siliang; Wang Donghui; Hou Chaohuan

    2012-01-01

    A low-power register file is designed by using a low-swing strategy and modified NAND address decoders. The proposed low-swing strategy is based on the feedback scheme and uses dynamic logic to reduce the active feedback power. This method contains two parts: WRITE and READ strategy. In the WRITE low-swing scheme, the modified memory cell is used to support low-swing WRITE. The modified NAND decoder not only dissipates less power, but also enables a great deal of area reduction. Compared with the conventional single-ended register file, the low-swing strategy saves 34.5% and 51.15% bit-line power in WRITE and READ separately. The post simulation results indicate a 39.4% power improvement when the twelve ports are all busy. (semiconductor integrated circuits)

  9. Research on low radiation doses - A better understanding of low doses

    International Nuclear Information System (INIS)

    2016-01-01

    Radiation doses below 100 mSv are called low doses. Epidemiological research on the health hazards of low doses are difficult to do because numerous pathologies, particularly cancer, appear lifelong for genetical or environmental causes without any link with irradiation and it is very difficult to identify the real cause of a cancer. Another concern is that the impact on human health is weak and are observed only after a long period after irradiation. These features make epidemiological studies cumbersome to implement since they require vast cohorts and a very long-term follow-up. The extrapolation of the effects of higher doses to the domain of low doses does not meet reality and it is why the European Union takes part into the financing of such research. In order to gain efficiency, scientists work together through various European networks among them: HLEG (High Level Expert Group On European Low Dose Risk Research) or MELODI (Multidisciplinary European Low Dose Initiative). Several programs are underway or have been recently launched: -) the impact of Cesium contamination on children's health (Epice program), -) the study of the impact of medical imaging on children, -) the study of the health of children living near nuclear facilities, -) the relationship between radon and lung cancer, -) the effect of occupational low radiation doses, -) the effect of uranium dissolved in water on living organisms (Envirhom program). (A.C.)

  10. Performance of low-temperature district heating for low-energy houses

    DEFF Research Database (Denmark)

    Brand, Marek; Dalla Rosa, Alessandro; Svendsen, Svend

    2010-01-01

    A Low Energy District Heating (LEDH) network supplying district heating water with temperature 50°C was built in Lærkehaven-Lystrup, Denmark, as a part of the ongoing “Energy Technology Development and Demonstration Programme” [EUDP, 2008] focused on “CO2-reduction in low energy buildings and com...

  11. Low-voltage gyrotrons

    International Nuclear Information System (INIS)

    Glyavin, M. Yu.; Zavolskiy, N. A.; Sedov, A. S.; Nusinovich, G. S.

    2013-01-01

    For a long time, the gyrotrons were primarily developed for electron cyclotron heating and current drive of plasmas in controlled fusion reactors where a multi-megawatt, quasi-continuous millimeter-wave power is required. In addition to this important application, there are other applications (and their number increases with time) which do not require a very high power level, but such issues as the ability to operate at low voltages and have compact devices are very important. For example, gyrotrons are of interest for a dynamic nuclear polarization, which improves the sensitivity of the nuclear magnetic resonance spectroscopy. In this paper, some issues important for operation of gyrotrons driven by low-voltage electron beams are analyzed. An emphasis is made on the efficiency of low-voltage gyrotron operation at the fundamental and higher cyclotron harmonics. These efficiencies calculated with the account for ohmic losses were, first, determined in the framework of the generalized gyrotron theory based on the cold-cavity approximation. Then, more accurate, self-consistent calculations for the fundamental and second harmonic low-voltage sub-THz gyrotron designs were carried out. Results of these calculations are presented and discussed. It is shown that operation of the fundamental and second harmonic gyrotrons with noticeable efficiencies is possible even at voltages as low as 5–10 kV. Even the third harmonic gyrotrons can operate at voltages about 15 kV, albeit with rather low efficiency (1%–2% in the submillimeter wavelength region).

  12. Low-frequency-noise complaints

    DEFF Research Database (Denmark)

    Pedersen, Christian Sejer; Møller, Henrik; Persson-Waye, Kerstin

    2008-01-01

    From 203 cases of low-frequency complaints a random selection of twenty-one cases were investigated. The main aim of the investigation was to answer the question whether the annoyance is caused by an external physical sound or by a physically non-existing sound, i.e. low-frequency tinnitus. Noise...... of the complainants are annoyed by a physical sound (20-180 Hz), while others suffer from low-frequency tinnitus (perceived frequency 40-100 Hz). Physical sound at frequencies below 20 Hz (infrasound) is not responsible for the annoyance - or at all audible - in any of the investigated cases, and none...... of the complainants has extraordinary hearing sensitivity at low frequencies. For comparable cases of low-frequency noise complaints in general, it is anticipated that physical sound is responsible in a substantial part of the cases, while low-frequency tinnitus is responsible in another substantial part of the cases....

  13. Low cycle fatigue behaviors of low alloy steels in 310 .deg. C deoxygenated water

    International Nuclear Information System (INIS)

    Jang, Hun

    2008-02-01

    After low cycle fatigue tests of SA508 Gr.1a low alloy steel in 310 .deg. C deoxygenated water, the fatigue surface and the sectioned area of specimens were observed to understand the effect of the cyclic strain rate on the environmentally assisted cracking behaviors. From the fatigue crack morphologies of the specimen tested at a strain rate of 0.008 %/s, unclear ductile striations and blunt crack tip were observed. So, metal dissolution could be the main cracking mechanism of the material at the strain rate. On the other hand, on the fatigue surface of the specimen tested at strain rates of 0.04 and 0.4 %/s, the brittle cracks and the flat facets, which are the evidence of the hydrogen induced cracking, were observed. Also, the tendency of linkage between the main crack and micro-cracks was observed on the sectioned area. Therefore, the main cracking mechanism at the strain rates of 0.04 and 0.4 %/s could be the hydrogen induced cracking. Additionally, the evidence of the dissolved MnS inclusions was observed on the fatigue surface from energy dispersive x-ray spectrometer analyses. So, despite of the low sulfur content of the test material, the sulfides seem to contribute to environmentally assisted cracking of SA508 Gr.1a low alloy steel in 310 .deg. C deoxygenated water. Additionally, our experimental fatigue life data of SA508 Gr.1a low alloy steel (heat A) showed a consistent difference with statistical model produced in argon national laboratory. So, additional low cycle fatigue tests of other heat SA508 Gr.1a (heat B) and SA508 Gr.3 low alloy steels were performed to investigate the effect of material variability on fatigue behaviors of low alloy steels in 310 .deg. C deoxygenated water. In results, the fatigue lives of three low alloy steels were increased following order: SA508 Gr.1a low alloy steel - heat A, SA508 Gr.3 low alloy steel, and SA508 Gr.1a low alloy steel - heat B. From microstructure observation, the fatigue surface of SA508 Gr.1a low alloy

  14. Jenis dan Status Konservasi Ikan Hiu yang Tertangkap di Tempat Pelelangan Ikan (TPI Labuan Bajo, Manggarai Barat, Flores

    Directory of Open Access Journals (Sweden)

    Ismail Syakurachman Alaydrus

    2016-03-01

    Full Text Available The study aimed to determine the types of sharks are caught, sold and conservation status in the fish auction place (TPI Labuan Bajo, West Manggarai, Flores, East Nusa Tenggara have been conducted in February and March 2014 in Labuan Bajo. The research method was the survey method and used Market Survey sampling techniques and identification by Rapid Assessment method. Descriptively analyzed data, displayed in the form of narration and a table. Based on the results of the study, found 114 individual sharks, 55 individual males, 59 females were classified into three orders, namely Orectolobiformes, Lamniformes, and Carcharhiniformes; 4 families that Carcharhinidae, Odontaspididae, Rhynchobatidae, and Ginglymostomatidae; 5 genera namely Carcharhinus, Triaenodon, Rhyncobatus, Prionace, and Rhizoprionodon and 9 types of sharks that Carcharhinus melanopterus, Triaenodon obesus, Carcharhinus limbatus, Carcharhinus taurus, Carcharhinus amblyrhynchos, Rhynchobatus australiae, Prionace glauca, Rhizoprionodon acutus, and Nebrius ferrugineus. Based on the state of conservation, shark found in Labuan Bajo TPI classified Vulnerable and Near Threatened, the dominant type of shark found is Carcharhinus melanopterus (91 fishes while the least was found is Rhynchobatus australiae, Prionace glauca, Rhizoprionodon acutus, and Nebrius ferrugineus (each 1 individual.

  15. Distribution of the Chuckwalla, Western Burrowing Owl, and Six Bat Species on the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Cathy A. Willis

    1997-05-01

    Field Surveys were conducted in 1996 to determine the current distribution of several animal species of concern on the Nevada Test Site (NTS). They included the chuckwall (Sauromalus obesus), western burrowing owl (Speotyto cunicularia), and six species of bats. Nineteen chuckwallas and 118 scat locations were found during the chuckwalla field study. Eighteen western burrowing owls were found at 12 sighting locations during the 1996 field study. Of the eleven bat species of concern which might occur on the NTS, five, and possibly six, were captured during this survey. The U.S. Department of Energy, Nevada Operations Office, takes certain management actions to protect and conserve the chuckwalla, western burrowing owl, and bats on the NTS. These actions are described and include: (1) conducting surveys at sites of proposed land-disturbing activities (2) altering projects whenever possible to avoid or minimize impacts to these species (3) maintaining a geospatial database of known habitat for species of concern (4) sharing sighting and trap location data gathered on the NTS with other local land and resource managers, and (5) conducting periodic field surveys to monitor these species distribution and relative abundance on the NTS.

  16. Error Analysis of High Frequency Core Loss Measurement for Low-Permeability Low-Loss Magnetic Cores

    DEFF Research Database (Denmark)

    Niroumand, Farideh Javidi; Nymand, Morten

    2016-01-01

    in magnetic cores is B-H loop measurement where two windings are placed on the core under test. However, this method is highly vulnerable to phase shift error, especially for low-permeability, low-loss cores. Due to soft saturation and very low core loss, low-permeability low-loss magnetic cores are favorable...... in many of the high-efficiency high power-density power converters. Magnetic powder cores, among the low-permeability low-loss cores, are very attractive since they possess lower magnetic losses in compared to gapped ferrites. This paper presents an analytical study of the phase shift error in the core...... loss measuring of low-permeability, low-loss magnetic cores. Furthermore, the susceptibility of this measurement approach has been analytically investigated under different excitations. It has been shown that this method, under square-wave excitation, is more accurate compared to sinusoidal excitation...

  17. Low-level effects

    International Nuclear Information System (INIS)

    Devine, R.T.; Chaput, R.L.

    1987-01-01

    Risk assignments can be made to given practices involving exposure to radiation, because sufficient data are available for the effects of high-dose, low-LET radiation and because sufficient exists in the methods of extrapolation to low doses and low dose rates. The confidence in the extrapolations is based on the fact that the risk is not expected to be overestimated, using the assumptions made (as opposed to the possibility that the extrapolations represent an accurate estimate of the risk). These risk estimates have been applied to the selection of permissible exposure levels, to show that various amounts of radiation involve no greater risk to the worker than the risk expected in another industry that is generally considered safe. The setting of standards for protection from exposure to low levels of ionizing radiation is made by expert committees at the national and international levels who weigh social factors as well as scientific factors. Data on low-level effects may be applied when assigning a ''probability of causation'' to a certain exposure of radiation. This has become a prominent method for arriving at an equitable award for damages caused by such exposure. The generation of these tables requires as many (if not more) social and political considerations as does the setting up of protection criteria. It is impossible to extract a purely scientific conclusion solely from the protection standards and other legal decisions. Sufficient information exists on low-LET radiation that safety standards for exposure can be rationally (if not scientifically) agreed upon

  18. Low doses effects

    International Nuclear Information System (INIS)

    Tubiana, M.

    1997-01-01

    In this article is asked the question about a possible carcinogens effect of low dose irradiation. With epidemiological data, knowledge about the carcinogenesis, the professor Tubiana explains that in spite of experiments made on thousand or hundred of thousands animals it has not been possible to bring to the fore a carcinogens effect for low doses and then it is not reasonable to believe and let the population believe that low dose irradiation could lead to an increase of neoplasms and from this point of view any hardening of radiation protection standards could in fact, increase anguish about ionizing radiations. (N.C.)

  19. Association between low lean mass and low bone mineral density in 653 women with hip fracture: does the definition of low lean mass matter?

    Science.gov (United States)

    Di Monaco, Marco; Castiglioni, Carlotta; Di Monaco, Roberto; Tappero, Rosa

    2017-12-01

    Loss of both muscle and bone mass results in fragility fractures with increased risk of disability, poor quality of life, and death. Our aim was to assess the association between low appendicular lean mass (aLM) defined according to different criteria and low bone mineral density (BMD) in hip-fracture women. Six hundred fifty-three women admitted to our rehabilitation hospital underwent dual energy X-ray absorptiometry 19.1 ± 4.1 (mean ± SD) days after hip-fracture occurrence. Low aLM was identified according to either Baumgartner's definition (aLM/height 2 less than two standard deviations below the mean of the young reference group) or FNIH criteria: aLM definition, the association between low aLM/height 2 and low BMD was significant: χ 2 (1, n = 653) = 8.52 (p = 0.004), but it was erased by adjustments for age and fat mass. Using the FNIH definition the association between low aLM and low BMD was significant: χ 2 (1, n = 653) = 42.5 (p definition based on aLM/BMI ratio the association between low aLM/BMI ratio and low BMD was nonsignificant: χ 2 (1, n = 653) = 0.003 (p = 0.957). The association between low aLM and low BMD in women with hip fracture dramatically depends on the adopted definition of low aLM. FNIH threshold for aLM (<15.02 kg) emerges as a useful tool to capture women with damage of the muscle-bone unit.

  20. Effects of a low-intensity intervention that prescribed a low-carbohydrate vs. a low-fat diet in obese, diabetic participants.

    Science.gov (United States)

    Iqbal, Nayyar; Vetter, Marion L; Moore, Reneé H; Chittams, Jesse L; Dalton-Bakes, Cornelia V; Dowd, Monique; Williams-Smith, Catherine; Cardillo, Serena; Wadden, Thomas A

    2010-09-01

    Low-carbohydrate diets have been associated with significant reductions in weight and HbA(1c) in obese, diabetic participants who received high-intensity lifestyle modification for 6 or 12 months. This investigation sought to determine whether comparable results to those of short-term, intensive interventions could be achieved over a 24-month study period using a low-intensity intervention that approximates what is feasible in outpatient practice. A total of 144 obese, diabetic participants were randomly assigned to a low-carbohydrate diet (low fat diet (fat with a deficit of 500 kcal/day). Participants were provided weekly group nutrition education sessions for the first month, and monthly sessions thereafter through the end of 24 months. Weight, HbA(1c), glucose, and lipids were measured at baseline and 6, 12, and 24 months. Of the 144 enrolled participants, 68 returned for the month 24 assessment visit. Weights were retrieved from electronic medical records for an additional 57 participants (total, 125 participants) at month 24. All participants with a baseline measurement and at least one of the three other measurements were included in the mixed-model analyses (n = 138). The low-intensity intervention resulted in modest weight loss in both groups at month 24. At this time, participants in the low-carbohydrate group lost 1.5 kg, compared to 0.2 kg in the low-fat group (P = 0.147). Lipids, glycemic indexes, and dietary intake did not differ between groups at month 24 (or at months 6 or 12) (ClinicalTrials.gov number, NCT00108459).

  1. Very low-energy and low-fluence ion beam bombardment of naked plasmid DNA

    International Nuclear Information System (INIS)

    Norarat, R.; Semsang, N.; Anuntalabhochai, S.; Yu, L.D.

    2009-01-01

    Ion beam bombardment of biological organisms has been recently applied to mutation breeding of both agricultural and horticultural plants. In order to explore relevant mechanisms, this study employed low-energy ion beams to bombard naked plasmid DNA. The study aimed at simulation of the final stage of the process of the ion beam bombardment of real cells to check whether and how very low-energy and low-fluence of ions can induce mutation. Argon and nitrogen ions at 5 keV and 2.5 keV respectively bombarded naked plasmid DNA pGFP to very low-fluences, an order of 10 13 ions/cm 2 . Subsequently, DNA states were analyzed using electrophoresis. Results provided evidences that the very low-energy and low-fluence ion bombardment indeed altered the DNA structure from supercoil to short linear fragments through multiple double strand breaks and thus induced mutation, which was confirmed by transfer of the bombarded DNA into bacteria Escherichia coli and subsequent expression of the marker gene.

  2. Low-level Radioactivity Measurements

    International Nuclear Information System (INIS)

    Churtgen, C.

    2007-01-01

    The low-level radioactivity measurements service performs measurements of alpha or beta emitters on various types of low-radioactivity samples (biological and environmental) from internal and external clients. to maintain and develop techniques concerning the measurement of low-level radioactivity of alpha and beta emitting radionuclides in environmental or biological samples; to measure these samples by means of low-background counters (liquid scintillators, proportional counters, ZnS counters and alpha-spectrometers); to support and advise the nuclear and non-nuclear industry on problems of radioactive contamination or low level radioactivity measurements; to maintain the quality assurance system according to the ISO17025 standard for which we obtained the Beltest accreditation in 1998; to assess the internal dose from occupational intakes of radionuclides for workers of the nuclear industry;

  3. Exploring the limits: A low-pressure, low-temperature Haber-Bosch process

    Science.gov (United States)

    Vojvodic, Aleksandra; Medford, Andrew James; Studt, Felix; Abild-Pedersen, Frank; Khan, Tuhin Suvra; Bligaard, T.; Nørskov, J. K.

    2014-04-01

    The Haber-Bosch process for ammonia synthesis has been suggested to be the most important invention of the 20th century, and called the ‘Bellwether reaction in heterogeneous catalysis’. We examine the catalyst requirements for a new low-pressure, low-temperature synthesis process. We show that the absence of such a process for conventional transition metal catalysts can be understood as a consequence of a scaling relation between the activation energy for N2 dissociation and N adsorption energy found at the surface of these materials. A better catalyst cannot obey this scaling relation. We define the ideal scaling relation characterizing the most active catalyst possible, and show that it is theoretically possible to have a low pressure, low-temperature Haber-Bosch process. The challenge is to find new classes of catalyst materials with properties approaching the ideal, and we discuss the possibility that transition metal compounds have such properties.

  4. Dielectric spectroscopy studies of low-disorder and low-dimensional materials

    OpenAIRE

    Tripathi, Pragya

    2016-01-01

    In this thesis we employ dielectric spectroscopy (in different implementations) to study the dielectric properties of different materials ranging from completely disordered supercooled liquids to low-disorder solids with only ratcheting reorientational motions, to low-dimensional systems such as thin films or needle-like crystals. The probed material properties include the electrical conductivity, the space-charge processes due to sample heterogeneities, molecular dynamics, hydrogen-bond dyna...

  5. Low glycaemic index, or low glycaemic load, diets for diabetes mellitus.

    Science.gov (United States)

    Thomas, Diana; Elliott, Elizabeth J

    2009-01-21

    The aim of diabetes management is to normalise blood glucose levels, since improved blood glucose control is associated with reduction in development, and progression, of complications. Nutritional factors affect blood glucose levels, however there is currently no universal approach to the optimal dietary treatment for diabetes. There is controversy about how useful the glycaemic index (GI) is in diabetic meal planning. Improved glycaemic control through diet could minimise medications, lessen risk of diabetic complications, improve quality of life and increase life expectancy. To assess the effects of low glycaemic index, or low glycaemic load, diets on glycaemic control in people with diabetes. We performed electronic searches of The Cochrane Library, MEDLINE, EMBASE and CINAHL with no language restriction. We assessed randomised controlled trials of four weeks or longer that compared a low glycaemic index, or low glycaemic load, diet with a higher glycaemic index, or load, or other diet for people with either type 1 or 2 diabetes mellitus, whose diabetes was not already optimally controlled. Two reviewers independently extracted data on study population, intervention and outcomes for each included study, using standardised data extraction forms. Eleven relevant randomised controlled trials involving 402 participants were identified. There was a significant decrease in the glycated haemoglobin A1c (HbA1c) parallel group of trials, the weighted mean difference (WMD) was -0.5% with a 95% confidence interval (CI) of - 0.9 to -0.1, P = 0.02; and in the cross-over group of trials the WMD was -0.5% with a 95% CI of -1.0 to -0.1, P = 0.03. Episodes of hypoglycaemia were significantly fewer with low compared to high GI diet in one trial (difference of -0.8 episodes per patient per month, P low-GI diet compared to measured carbohydrate exchange diet in another study (35% versus 66%, P = 0.006). No study reported on mortality, morbidity or costs. A low-GI diet can improve

  6. Satellite-aided survey sampling and implementation in low- and middle-income contexts: a low-cost/low-tech alternative.

    Science.gov (United States)

    Haenssgen, Marco J

    2015-01-01

    The increasing availability of online maps, satellite imagery, and digital technology can ease common constraints of survey sampling in low- and middle-income countries. However, existing approaches require specialised software and user skills, professional GPS equipment, and/or commercial data sources; they tend to neglect spatial sampling considerations when using satellite maps; and they continue to face implementation challenges analogous to conventional survey implementation methods. This paper presents an alternative way of utilising satellite maps and digital aides that aims to address these challenges. The case studies of two rural household surveys in Rajasthan (India) and Gansu (China) compare conventional survey sampling and implementation techniques with the use of online map services such as Google, Bing, and HERE maps. Modern yet basic digital technology can be integrated into the processes of preparing, implementing, and monitoring a rural household survey. Satellite-aided systematic random sampling enhanced the spatial representativeness of the village samples and entailed savings of approximately £4000 compared to conventional household listing, while reducing the duration of the main survey by at least 25 %. This low-cost/low-tech satellite-aided survey sampling approach can be useful for student researchers and resource-constrained research projects operating in low- and middle-income contexts with high survey implementation costs. While achieving transparent and efficient survey implementation at low costs, researchers aiming to adopt a similar process should be aware of the locational, technical, and logistical requirements as well as the methodological challenges of this strategy.

  7. High-precision and low-cost vibration generator for low-frequency calibration system

    Science.gov (United States)

    Li, Rui-Jun; Lei, Ying-Jun; Zhang, Lian-Sheng; Chang, Zhen-Xin; Fan, Kuang-Chao; Cheng, Zhen-Ying; Hu, Peng-Hao

    2018-03-01

    Low-frequency vibration is one of the harmful factors that affect the accuracy of micro-/nano-measuring machines because its amplitude is significantly small and it is very difficult to avoid. In this paper, a low-cost and high-precision vibration generator was developed to calibrate an optical accelerometer, which is self-designed to detect low-frequency vibration. A piezoelectric actuator is used as vibration exciter, a leaf spring made of beryllium copper is used as an elastic component, and a high-resolution, low-thermal-drift eddy current sensor is applied to investigate the vibrator’s performance. Experimental results demonstrate that the vibration generator can achieve steady output displacement with frequency range from 0.6 Hz to 50 Hz, an analytical displacement resolution of 3.1 nm and an acceleration range from 3.72 mm s-2 to 1935.41 mm s-2 with a relative standard deviation less than 1.79%. The effectiveness of the high-precision and low-cost vibration generator was verified by calibrating our optical accelerometer.

  8. Low carbon development. Key issues

    Energy Technology Data Exchange (ETDEWEB)

    Urban, Frauke; Nordensvaard, Johan (eds.)

    2013-03-07

    This comprehensive textbook addresses the interface between international development and climate change in a carbon constrained world. It discusses the key conceptual, empirical and policy-related issues of low carbon development and takes an international and interdisciplinary approach to the subject by drawing on insights from across the natural sciences and social sciences whilst embedding the discussion in a global context. The first part explores the concept of low carbon development and explains the need for low carbon development in a carbon constrained world. The book then discusses the key issues of socio-economic, political and technological nature for low carbon development, exploring topics such as the political economy, social justice, financing and carbon markets, and technologies and innovation for low carbon development. This is followed by key issues for low carbon development in policy and practice, which is presented based on cross-cutting issues such as low carbon energy, forestry, agriculture and transportation. Afterwards, practical case studies are discussed from low carbon development in low income countries in Africa, middle income countries in Asia and Latin America and high income countries in Europe and North America.

  9. Low energy, low cost, efficient CO{sub 2} capture

    Energy Technology Data Exchange (ETDEWEB)

    Michael C. Trachtenberg; Lihong Bao; David A. Smith; Remy Dumortier [Carbozyme, Inc., Monmouth Junction, NJ (United States)

    2006-07-01

    This paper discusses the development and some characteristics of a new, enzyme-based, contained liquid membrane contactor to capture CO{sub 2}. The enzyme carbonic anhydrase catalyzes the removal of CO{sub 2} while the membrane contactor increases the surface area to allow the reduction of the size of the system. The modular system design is easily scaled to any required size reducing the investment costs. The system captures CO{sub 2} at a low energy and low cost promising to be a cost effective technology for CO{sub 2} capture. 5 refs., 7 figs.

  10. Low-Power, Low-Voltage Analog to Digital ΣΔ

    DEFF Research Database (Denmark)

    Wismar, Ulrik Sørensen

    2007-01-01

    , and since long operation time is required, low supply voltage and low power consumption are of paramount importance. Consequently, various topologies have been compared to nd the most power ecient audio frequency modulator topology. Chapter 4 of this thesis compares power consumption of two of the most...... prevalent topologies, the single-loop modulator with integration in discrete time and the single-loop modulator with integration in continuous time. Both modulator topologies are with feedback, and all intermediate signals are in the voltage mode. Chapter 5 treats a modulator without feedback. Another...

  11. Database of Low-e Storm Window Energy Performance across U.S. Climate Zones

    Energy Technology Data Exchange (ETDEWEB)

    Culp, Thomas D.; Cort, Katherine A.

    2014-09-04

    This is an update of a report that describes process, assumptions, and modeling results produced Create a Database of U.S. Climate-Based Analysis for Low-E Storm Windows. The scope of the overall effort is to develop a database of energy savings and cost effectiveness of low-E storm windows in residential homes across a broad range of U.S. climates using the National Energy Audit Tool (NEAT) and RESFEN model calculations. This report includes a summary of the results, NEAT and RESFEN background, methodology, and input assumptions, and an appendix with detailed results and assumptions by cliamte zone.

  12. Health effect of low dose/low dose rate radiation

    International Nuclear Information System (INIS)

    Kodama, Seiji

    2012-01-01

    The clarified and non-clarified scientific knowledge is discussed to consider the cause of confusion of explanation of the title subject. The low dose is defined roughly lower than 200 mGy and low dose rate, 0.05 mGy/min. The health effect is evaluated from 2 aspects of clinical symptom/radiation hazard protection. In the clinical aspect, the effect is classified in physical (early and late) and genetic ones, and is classified in stochastic (no threshold value, TV) and deterministic (with TV) ones from the radioprotection aspect. Although the absence of TV in the carcinogenic and genetic effects has not been proved, ICRP employs the stochastic standpoint from the safety aspect for radioprotection. The lowest human TV known now is 100 mGy, meaning that human deterministic effect would not be generated below this dose. Genetic deterministic effect can be observable only in animal experiments. These facts suggest that the practical risk of exposure to <100 mGy in human is the carcinogenesis. The relationship between carcinogenic risk in A-bomb survivors and their exposed dose are found fitted to the linear no TV model, but the epidemiologic data, because of restriction of subject number analyzed, do not always mean that the model is applicable even below the dose <100 mGy. This would be one of confusing causes in explanation: no carcinogenic risk at <100 mGy or risk linear to dose even at <100 mGy, neither of which is scientifically conclusive at present. Also mentioned is the scarce risk of cancer in residents living in the high background radiation regions in the world in comparison with that in the A-bomb survivors exposed to the chronic or acute low dose/dose rate. Molecular events are explained for the low-dose radiation-induced DNA damage and its repair, gene mutation and chromosome aberration, hypothesis of carcinogenesis by mutation, and non-targeting effect of radiation (bystander effect and gene instability). Further researches to elucidate the low dose

  13. Negative beliefs about low back pain are associated with persistent high intensity low back pain.

    Science.gov (United States)

    Ng, Sin Ki; Cicuttini, Flavia M; Wang, Yuanyuan; Wluka, Anita E; Fitzgibbon, Bernadette; Urquhart, Donna M

    2017-08-01

    While previous cross-sectional studies have found that negative beliefs about low back pain are associated with pain intensity, the relationship between back beliefs and persistent low back pain is not well understood. This cohort study aimed to examine the role of back beliefs in persistent low back pain in community-based individuals. A hundred and ninety-two participants from a previous musculoskeletal health study were invited to take part in a two-year follow-up study. Beliefs about back pain were assessed by the Back Beliefs Questionnaire (BBQ) at baseline and low back pain intensity was measured by the Chronic Pain Grade Questionnaire at baseline and follow-up. Of the 150 respondents (78.1%), 16 (10.7%) reported persistent high intensity low back pain, 12 (8.0%) developed high intensity low back pain, in 16 (10.7%) their high intensity low back pain resolved and 106 (70.7%) experienced no high intensity low back pain. While participants were generally positive about low back pain (BBQ mean (SD) = 30.2 (6.4)), those with persistent high intensity pain reported greater negativity (BBQ mean (SD) = 22.6 (4.9)). Negative beliefs about back pain were associated with persistent high intensity low back pain after adjusting for confounders (M (SE) = 23.5 (1.6) vs. >30.1 (1.7), p back beliefs were associated with persistent high intensity low back pain over 2 years in community-based individuals. While further longitudinal studies are required, these findings suggest that targeting beliefs in programs designed to treat and prevent persistent high intensity low back pain may be important.

  14. Low-gradient aortic stenosis.

    Science.gov (United States)

    Clavel, Marie-Annick; Magne, Julien; Pibarot, Philippe

    2016-09-07

    An important proportion of patients with aortic stenosis (AS) have a 'low-gradient' AS, i.e. a small aortic valve area (AVA gradient (gradient discrepancy raises uncertainty about the actual stenosis severity and thus about the indication for aortic valve replacement (AVR) if the patient has symptoms and/or left ventricular (LV) systolic dysfunction. The most frequent cause of low-gradient (LG) AS is the presence of a low LV outflow state, which may occur with reduced left ventricular ejection fraction (LVEF), i.e. classical low-flow, low-gradient (LF-LG), or preserved LVEF, i.e. paradoxical LF-LG. Furthermore, a substantial proportion of patients with AS may have a normal-flow, low-gradient (NF-LG) AS: i.e. a small AVA-low-gradient combination but with a normal flow. One of the most important clinical challenges in these three categories of patients with LG AS (classical LF-LG, paradoxical LF-LG, and NF-LG) is to differentiate a true-severe AS that generally benefits from AVR vs. a pseudo-severe AS that should be managed conservatively. A low-dose dobutamine stress echocardiography may be used for this purpose in patients with classical LF-LG AS, whereas aortic valve calcium scoring by multi-detector computed tomography is the preferred modality in those with paradoxical LF-LG or NF-LG AS. Although patients with LF-LG severe AS have worse outcomes than those with high-gradient AS following AVR, they nonetheless display an important survival benefit with this intervention. Some studies suggest that transcatheter AVR may be superior to surgical AVR in patients with LF-LG AS. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

  15. Low-level Radioactivity Measurements

    International Nuclear Information System (INIS)

    Hurtgen, C.

    2002-01-01

    The objectives of the research performed in the area of low-level radioactivity measurements are (1) to maintain and develop techniques for the measurement of low-level environmental and biological samples, (2) to measure these samples by means of low-background counters (liquid scintillators, proportional counters, ZnS counters, alpha spectrometry), (3) to support and advise the nuclear and non-nuclear industry on problems of radioactive contamination and low-level radioactivity measurements; (4) to maintain and improve the quality assurance system according to the ISO17025 standard; and (5) to assess the internal dose from occupational intakes of radionuclides of workers of the nuclear industry. Progress and achievements in these areas in 2001 are reported

  16. Low-level Radioactivity Measurements

    International Nuclear Information System (INIS)

    Hurtgen, C.

    2001-01-01

    The objectives of the research performed in the area of low-level radioactivity measurements are (1) to maintain and develop techniques for the measurement of low-level environmental and biological samples, (2) to measure these samples by means of low-background counters (liquid scintillators, proportional counters, ZnS counters, alpha spectrometry), (3) to support and advice the nuclear and non-nuclear industry in matters concerning radioactive contamination and/or low-level radioactivity measurements; (4) to maintain the quality assurance system according to the EN45001/ISO17025 standard; and (5) to assess the internal dose from occupational intakes of radionuclides of workers of the nuclear industry. Progress and achievements in these areas in 2000 are reported

  17. Participatory perspectives for the low skilled and the low educated: how can media literacy influence the social and economic participation of the low skilled and the low educated?

    NARCIS (Netherlands)

    Moekotte, Paulo; Brand-Gruwel, Saskia; Ritzen, Henk

    2018-01-01

    We assume that social media use contributes to employability and sociality and media literacy complements a basic set of skills. Especially the low skilled and low educated lack media literacy, which contributes to their precarious situation and increases a participation gap. A database search for

  18. Reducing serious fall-related injuries in acute hospitals: are low-low beds a critical success factor?

    Science.gov (United States)

    Barker, Anna; Kamar, Jeannette; Tyndall, Tamara; Hill, Keith

    2013-01-01

    This article is a report of a study of associations between occurrence of serious fall-related injuries and implementation of low-low beds at The Northern Hospital, Victoria, Australia. A 9-year evaluation at The Northern Hospital found an important reduction in fall-related injuries after the 6-PACK falls prevention program was implemented. Low-low beds are a key component of the 6-PACK that aims to decrease fall-related injuries. A retrospective cohort study. Retrospective audit of The Northern Hospital inpatients admitted between 1999-2009. Changes in serious fall-related injuries throughout the period and associations with available low-low beds were analysed using Poisson regression. During the observation of 356,158 inpatients, there were 3946 falls and 1005 fall-related injuries of which 60 (5·9%) were serious (55 fractures and five subdural haematomas). Serious fall-related injuries declined significantly throughout the period. When there was one low-low bed to nine or more standard beds there was no statistically significant decrease in serious fall-related injuries. An important reduction only occurred when there was one low-low bed to three standard beds. The 6-PACK program has been in place since 2002 at The Northern Hospital. Throughout this time serious fall-related injuries have decreased. There appears to be an association between serious fall-related injuries and the number of available low-low beds. Threshold numbers of these beds may be required to achieve optimal usability and effectiveness. A randomized controlled trial is required to give additional evidence for use of low-low beds for injury prevention in hospitals. © 2012 Blackwell Publishing Ltd.

  19. Low-pressure

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Richard [Membrane Technology And Research, Inc., Newark, CA (United States); Kniep, Jay [Membrane Technology And Research, Inc., Newark, CA (United States); Hao, Pingjiao [Membrane Technology And Research, Inc., Newark, CA (United States); Chan, Chi Cheng [Membrane Technology And Research, Inc., Newark, CA (United States); Nguyen, Vincent [Membrane Technology And Research, Inc., Newark, CA (United States); Huang, Ivy [Membrane Technology And Research, Inc., Newark, CA (United States); Amo, Karl [Membrane Technology And Research, Inc., Newark, CA (United States); Freeman, Brice [Membrane Technology And Research, Inc., Newark, CA (United States); Fulton, Don [Membrane Technology And Research, Inc., Newark, CA (United States); Ly, Jennifer [Membrane Technology And Research, Inc., Newark, CA (United States); Lipscomb, Glenn [Membrane Technology And Research, Inc., Newark, CA (United States); Lou, Yuecun [Membrane Technology And Research, Inc., Newark, CA (United States); Gogar, Ravikumar [Membrane Technology And Research, Inc., Newark, CA (United States)

    2015-01-29

    This final technical progress report describes work conducted by Membrane Technology and Research, Inc. (MTR) for the Department of Energy (DOE NETL) on development of low-pressure membrane contactors for carbon dioxide (CO2) capture from power plant flue gas (award number DE-FE0007553). The work was conducted from October 1, 2011 through September 30, 2014. The overall goal of this three-year project was to build and operate a prototype 500 m2 low-pressure sweep membrane module specifically designed to separate CO2 from coal-fired power plant flue gas. MTR was assisted in this project by a research group at the University of Toledo, which contributed to the computational fluid dynamics (CFD) analysis of module design and process simulation. This report details the work conducted to develop a new type of membrane contactor specifically designed for the high-gas-flow, low-pressure, countercurrent sweep operation required for affordable membrane-based CO2 capture at coal power plants. Work for this project included module development and testing, design and assembly of a large membrane module test unit at MTR, CFD comparative analysis of cross-flow, countercurrent, and novel partial-countercurrent sweep membrane module designs, CFD analysis of membrane spacers, design and fabrication of a 500 m2 membrane module skid for field tests, a detailed performance and cost analysis of the MTR CO2 capture process with low-pressure sweep modules, and a process design analysis of a membrane-hybrid separation process for CO2 removal from coal-fired flue gas. Key results for each major task are discussed in the report.

  20. Subjective annoyance caused by indoor low-level and low frequency noise and control method

    Institute of Scientific and Technical Information of China (English)

    DI Guo-qing; ZHANG Bang-jun; SHANG Qi

    2005-01-01

    The influence of low-level noise has not been widely noticed. This paper discovered that low-level and low frequency noise(Aweighted equivalent level Leq < 45 dB) causes higher probability of subjective annoyance. The fuzzy mathematic principle was applied to deal with the threshold level of subjective annoyance from noise in this study; there is preferable relationship between the indoor noise and noise annoyance at low frequency noise level. Study indicated at the same centered noise level, the change of annoyance probability is mainly caused by the change of the frequency spectrum characteristic of the indoor noise. Under low noise level environment, without change of the medium-low frequency noise, the slight increase of medium-high frequency noise level with the help of noise sheltering effect can significantly reduce the noise annoyance. This discovery brings a new resolution on how to improve the environmental quality of working or living places. A noise control model is given in this study according to the acoustic analysis.

  1. Low-T, Low-Q Cryocoolers for Science Instruments

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of the planned research is to advance the current space science instruments through the development of light weight and low power cryocoolers. Currently,...

  2. Effect of low-frequency low-intensity ultrasound with microbubbles on prostate cancer hypoxia.

    Science.gov (United States)

    Hou, Rui; Xu, Yanjun; Lu, Qijie; Zhang, Yang; Hu, Bing

    2017-10-01

    Angiogenesis plays an important role in tumor growth, invasiveness, and metastasis. It is well established that prostate cancer is exposed to fluctuating oxygen tensions and both acute and chronic hypoxia exist, and these conditions can upregulate angiogenesis-associated proteins such as hypoxia-inducible factor 1 alpha and vascular endothelial growth factor A. Low-frequency low-intensity ultrasound with microbubbles can induce obvious microvessel damage in tumors, cause cell necrosis or apoptosis. However, there is no information about whether the blocking blood effect of low-frequency low-intensity ultrasound with microbubbles has an influence on hypoxia environment of prostate cancer. Therefore, we investigated the impact of different low-frequency low-intensity ultrasound with microbubbles radiation times on prostate tumors, observed the change in the hypoxia-inducible factor 1 alpha and vascular endothelial growth factor A protein levels, as well as cell proliferation, apoptosis, and tumor volume. The results indicated that as the radiation was repeated four times on each treatment day, the effects of interruption were durable, the cell proliferation was inhibited, and apoptosis was promoted, and the hypoxia-inducible factor 1 alpha and vascular endothelial growth factor A expression levels were lower in the treatment group than in the control group. When the radiation was carried out once per treatment day, the hypoxia response was stimulated, the hypoxia-inducible factor 1 alpha and vascular endothelial growth factor A expression levels were higher compared with the control group, and cell proliferation was promoted. In addition, the tumor volume increased obviously in the hypoxia-stimulated group, whereas tumors grew slowly in the hypoxia-suppressed group. The results of this work demonstrated that under the same conditions, different radiation times of low-frequency low-intensity ultrasound with microbubbles affect the hypoxia response differently, and the

  3. Low-Activity Radioactive Wastes

    Science.gov (United States)

    In 2003 EPA published an Advance Notice of Proposed Rulemaking (ANPR) to collect public comment on alternatives for disposal of waste containing low concentrations of radioactive material ('low-activity' waste).

  4. Drug-induced low blood sugar

    Science.gov (United States)

    Drug-induced low blood sugar is low blood glucose that results from taking medicine. ... Low blood sugar (hypoglycemia) is common in people with diabetes who are taking insulin or other medicines to control their diabetes. ...

  5. Low level radiation: how low can you get?

    International Nuclear Information System (INIS)

    Townsley, M.

    1990-01-01

    Information stored on the world's largest data bank concerning the health of nuclear industry workers is to be handed over to researchers at Birmingham University by the US Department of Energy. The data bank contains detailed information on 300,000 nuclear employees, going back to the 1940s. Such a large sample size will allow the results of a previous study conducted on workers in the US nuclear industry to be verified. That study was concluded in 1978 and showed that the risk estimates set by the International Commission on Radiological Protection (ICRP) were between 10 and 30 times too low. The current ICRP estimate allows workers up to 50mSv of exposure to low level radiation per year. Risk estimates have been derived from data relating to the atomic bombings of Hiroshima and Nagasaki. However in those cases the radiation doses were relatively high but over a short period. In the nuclear industry the doses are lower but are long term and this may account for the apparent anomalies such as the incidence of leukaemia amongst children whose fathers have worked in the nuclear industry compared with that for the children whose fathers received radiation doses from the atomic bombings. It is expected the study will show that low-level radiation is more damaging than has previously been thought. (author)

  6. Advanced Computational Approaches for Characterizing Stochastic Cellular Responses to Low Dose, Low Dose Rate Exposures

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Bobby, R., Ph.D.

    2003-06-27

    OAK - B135 This project final report summarizes modeling research conducted in the U.S. Department of Energy (DOE), Low Dose Radiation Research Program at the Lovelace Respiratory Research Institute from October 1998 through June 2003. The modeling research described involves critically evaluating the validity of the linear nonthreshold (LNT) risk model as it relates to stochastic effects induced in cells by low doses of ionizing radiation and genotoxic chemicals. The LNT model plays a central role in low-dose risk assessment for humans. With the LNT model, any radiation (or genotoxic chemical) exposure is assumed to increase one¡¯s risk of cancer. Based on the LNT model, others have predicted tens of thousands of cancer deaths related to environmental exposure to radioactive material from nuclear accidents (e.g., Chernobyl) and fallout from nuclear weapons testing. Our research has focused on developing biologically based models that explain the shape of dose-response curves for low-dose radiation and genotoxic chemical-induced stochastic effects in cells. Understanding the shape of the dose-response curve for radiation and genotoxic chemical-induced stochastic effects in cells helps to better understand the shape of the dose-response curve for cancer induction in humans. We have used a modeling approach that facilitated model revisions over time, allowing for timely incorporation of new knowledge gained related to the biological basis for low-dose-induced stochastic effects in cells. Both deleterious (e.g., genomic instability, mutations, and neoplastic transformation) and protective (e.g., DNA repair and apoptosis) effects have been included in our modeling. Our most advanced model, NEOTRANS2, involves differing levels of genomic instability. Persistent genomic instability is presumed to be associated with nonspecific, nonlethal mutations and to increase both the risk for neoplastic transformation and for cancer occurrence. Our research results, based on

  7. Low Sex Drive in Women

    Science.gov (United States)

    Low sex drive in women Overview Women's sexual desires naturally fluctuate over the years. Highs and lows commonly coincide ... used for mood disorders also can cause low sex drive in women. If your lack of interest ...

  8. Low White Blood Cell Count

    Science.gov (United States)

    Symptoms Low white blood cell count By Mayo Clinic Staff A low white blood cell count (leukopenia) is a decrease ... of white blood cell (neutrophil). The definition of low white blood cell count varies from one medical ...

  9. Lowe Syndrome (Oculo-cerebro-renal Syndrome of Lowe: A Case Report from Eastern India

    Directory of Open Access Journals (Sweden)

    Dipankar Das

    2014-01-01

    Full Text Available Lowe syndrome (the oculocerebrorenal syndrome of Lowe, OCRL is a rare X-linked recessive metabolic disorder that primarily affects eyes, kidneys and brain. It is caused by the deficiency of enzyme phosphatidylinositol 4, 5-bisphosphate 5-phosphatase. The gene coding for this enzyme, OCRL1 and mutations in it are responsible to cause Lowe Syndrome. We report a 6 years old boy from Eastern India, with Lowe Syndrome. Diagnosis was suggested by typical features in the MRI of the brain along with other clinical feature and investigation.

  10. Low field-low cost: Can low-field magnetic resonance systems replace high-field magnetic resonance systems in the diagnostic assessment of multiple sclerosis patients?

    International Nuclear Information System (INIS)

    Ertl-Wagner, B.B.; Reith, W.; Sartor, K.

    2001-01-01

    As low-field MR imaging is becoming a widely used imaging technique, we aimed at a prospective assessment of differences in imaging quality between low- and high-field MR imaging in multiple sclerosis patients possibly interfering with diagnostic or therapeutic decision making. Twenty patients with clinically proven multiple sclerosis were examined with optimized imaging protocols in a 1.5- and a 0.23-T MR scanner within 48 h. Images were assessed independently by two neuroradiologists. No statistically significant interrater discrepancies were observed. A significantly lower number of white matter lesions could be identified in low-field MR imaging both on T1- and on T2-weighted images (T2: high field 700, low field 481; T1: high field 253, low field 177). A total of 114 enhancing lesions were discerned in the high-field MR imaging as opposed to 45 enhancing lesions in low-field MR imaging. Blood-brain barrier disruption was identified in 11 of 20 patients in the high-field MR imaging, but only in 4 of 20 patients in low-field MR imaging. Since a significantly lower lesion load is identified in low-field MR imaging than in high-field MR imaging, and blood-brain barrier disruption is frequently missed, caution must be exercised in interpreting a normal low-field MR imaging scan in a patient with clinical signs of multiple sclerosis and in interpreting a scan without enhancing lesions in a patient with known multiple sclerosis and clinical signs of exacerbation. (orig.)

  11. Desire to eat high- and low-fat foods following a low-fat dietary intervention.

    Science.gov (United States)

    Grieve, Frederick G; Vander Weg, Mark W

    2003-01-01

    This study examined changes in desires to eat high-fat and low-fat foods across an obesity treatment program. The hypotheses under examination were (1) preferences for low-fat foods would increase across time and (2) preferences for high-fat foods would decrease across time. Single-group, prospective examination of desires to eat 48 foods, categorized according to fat content, before and after the 16-week treatment program. University clinic, Memphis, Tennessee. 118 obese (mean weight = 194.4 lbs) women (mean age = 45.24 years) participating in an obesity treatment program. A 16-week cognitive-behavioral program for obesity. Desires to eat 48 foods varying in fat content and whether or not participants actually ate these foods. Analysis of variance, multiple regression, and paired t tests. The results indicate that during the program, preferences for low-fat foods increased, whereas preferences for high-fat foods decreased. These changes mirrored the changes in consumption of both low-fat and high-fat foods. Within a behavioral economic perspective, the reinforcement value of low-fat foods may increase following a low-fat dietary intervention, whereas the reinforcing properties of high-fat foods may decline. This is desirable as low-fat foods hold many advantages over high-fat foods in terms of weight maintenance.

  12. 49 CFR 231.4 - Fixed-end low-side gondola and low-side hopper cars.

    Science.gov (United States)

    2010-10-01

    ... cars. 231.4 Section 231.4 Transportation Other Regulations Relating to Transportation (Continued... Fixed-end low-side gondola and low-side hopper cars. (Cars with sides 36 inches or less above the floor are low-side cars.) (a) Hand brakes—(1) Number. Same as specified for “Box and other house cars” (see...

  13. Overview of Low-carbon Economy Research

    OpenAIRE

    Fu, Hui

    2010-01-01

    The paper has a detailed literature review in low-carbon economy research of academy circle in our country from three aspects that are conception and connotation of low-carbon economy, necessity and urgency of developing low-carbon economy and path choice of realizing low-carbon economy in our country. Low-carbon economy is the “green economy†that obtains the maximum output by discharging minimum greenhouse gases with the main characteristics of “three low and three high†that are low ...

  14. Does low surface brightness mean low density?

    NARCIS (Netherlands)

    deBlok, WJG; McGaugh, SS

    1996-01-01

    We compare the dynamical properties of two galaxies at identical positions on the Tully-Fisher relation, but with different surface brightnesses. We find that the low surface brightness galaxy UGC 128 has a higher mass-to-light ratio, and yet has lower mass densities than the high surface brightness

  15. Environmental conditions to achieve low adhesion and low friction on diamond surfaces

    International Nuclear Information System (INIS)

    Guo, Haibo; Qi, Yue

    2010-01-01

    The adhesion and friction of both diamond and diamond-like carbon coatings can be dramatically changed by active gases in the environment, such as hydrogen, water vapor and humid air, due to tribochemical reactions. To understand the atmospheric effects and to predict the optimized environmental conditions (gas species, pressure and temperature), the tribochemical reactions on diamond surfaces are modeled from first principles thermodynamics. The results show that both H 2 and a mixture of H 2 O plus O 2 (such as humid air) can effectively achieve low adhesion and low friction with a fully –H or –OH passivated surface at very low partial pressures. Water vapor itself can passivate diamond (1 1 1) and (1 0 0) surfaces into half –H and half –OH terminated surfaces, but only at unrealistically high partial pressures. Even a trace amount of oxygen combined with water vapor can significantly reduce the water partial pressure for passivation. In all tribochemical reactions considered, the partial pressure required to reach low adhesion and low friction increases rapidly with temperature, and diamond (1 0 0) surface requires less partial pressures than (1 1 1) surface for surface passivation

  16. Low-beta investment strategies

    OpenAIRE

    Korn, Olaf; Kuntz, Laura-Chloé

    2015-01-01

    This paper investigates investment strategies that exploit the low-beta anomaly. Although the notion of buying low-beta stocks and selling high-beta stocks is natural, a choice is necessary with respect to the relative weighting of high-beta stocks and low-beta stocks in the investment portfolio. Our empirical results for US large-cap stocks show that this choice is very important for the risk-return characteristics of the resulting portfolios and their sensitivities to common risk factors. W...

  17. Low sodium diet (image)

    Science.gov (United States)

    ... for you. Look for these words on labels: low-sodium, sodium-free, no salt added, sodium-reduced, ... for you. Look for these words on labels: low-sodium, sodium-free, no salt added, sodium-reduced, ...

  18. Low blood sugar - newborns

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007306.htm Low blood sugar - newborns To use the sharing features on this page, please enable JavaScript. A low blood sugar level in newborn babies is also ...

  19. Low lag luminescent phosphors

    International Nuclear Information System (INIS)

    1976-01-01

    The addition of potassium or rubidium salts to europium-activated fluorohalide phosphors produces X-ray screens with low lag, even at very low europium concentrations. The chemical preparation and afterglow test results are described

  20. Features of Physical and Neuro-Psychological Development of Children with Low, Very Low and Extremely Low Birth Weight in Different Age Periods of Life

    Directory of Open Access Journals (Sweden)

    I. A. Deev

    2016-01-01

    Full Text Available Analysis of features of physical and neuro-psychological development of children with low, very low and extremely low birth weight in different age periods is carried out according to cohort studies of newborns with different gestational age and birth weight, presented in electronic databases PubMed and Medscape. It is revealed that the overwhelming number of children with low, very low and extremely low birth weight, gain physical and neuro- psychological development impairments, hearing and vision disorders of varying severity, violation of motor function, intelligence and cognitive skills infringement in an older age. In this regard, it is actual not only to develop new neonatal reanimation and intensive care technologies, but also to ensure adequate prevention of preterm birth in the group of women with a high degree of perinatal risk. All this will further allow preventing increase in children with disabling conditions number among premature infants.

  1. Low Tyramine Headache Diet

    Science.gov (United States)

    ... Find A Provider Contact Membership Donate 25 Oct Low-Tyramine Diet for Migraine Posted at 17:16h ... and Diamond Headache Clinic Headache Diet Tags: headache , low tyramine diet , MAOI , tyramine No Comments Post A ...

  2. Low back pain - chronic

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007422.htm Low back pain - chronic To use the sharing features on this page, please enable JavaScript. Low back pain refers to pain that you feel in your ...

  3. Comparative analysis for low-mass and low-inertia dynamic balancing of mechanisms

    NARCIS (Netherlands)

    van der Wijk, V.; Demeulenaere, B.; Gosselin, C.M.; Herder, Justus Laurens

    2012-01-01

    Dynamic balance is an important feature of high speed mechanisms and robotics that need to minimize vibrations of the base. The main disadvantage of dynamic balancing, however, is that it is accompanied with a considerable increase in mass and inertia. Aiming at low-mass and low-inertia dynamic

  4. Correlates of Low Birth Weight

    Directory of Open Access Journals (Sweden)

    Ankur Barua MD, PhD

    2014-12-01

    Full Text Available Background. Low birth weight is the single most important factor that determines the chances of child survival. A recent annual estimation indicated that nearly 8 million infants are born with low birth weight in India. The infant mortality rate is about 20 times greater for all low birth weight babies. Methods. A matched case–control study was conducted on 130 low birth weight babies and 130 controls for 12 months (from August 1, 2007, to July 31, 2008 at the Central Referral Hospital, Tadong, East District of Sikkim, India. Data were analyzed using the Statistical Package for Social Sciences, version 10.0 for Windows. Chi-square test and multiple logistic regression were applied. A P value less than .05 was considered as significant. Results. In the first phase of this study, 711 newborn babies, borne by 680 mothers, were screened at the Central Referral Hospital of Sikkim during the 1-year study period, and the proportion of low birth weight babies was determined to be 130 (18.3%. Conclusion. Multiple logistic regression analysis, conducted in the second phase, revealed that low or middle socioeconomic status, maternal underweight, twin pregnancy, previous history of delivery of low birth weight babies, smoking and consumption of alcohol during pregnancy, and congenital anomalies had independent significant association with low birth weight in this study population.

  5. Low frequency noise study.

    Science.gov (United States)

    2007-04-01

    This report documents a study to investigate human response to the low-frequency : content of aviation noise, or low-frequency noise (LFN). The study comprised field : measurements and laboratory studies. The major findings were: : 1. Start-of-takeof...

  6. Self-replenishing low-adherence coatings

    NARCIS (Netherlands)

    Dikic, T.; Ming, W.; Benthem, van R.A.T.M.; With, de G.; Schmets, A.J.M.; Zwaag, van der S.

    2007-01-01

    Low-adherence coatings are widely used today since their water/oil repellency makes them easily cleanable (a well-known example is PTFE). The low surface tension is provided by fluorine- or silicon-containing species that are present at the film surface. Low adherence coatings have already been

  7. Low preveance ion source bridges low and high intensities in ion implantation

    International Nuclear Information System (INIS)

    Orr, F.D.; Mayhall, D.

    1976-01-01

    The Low Perveance Ion Source developed by Accelerators, Inc. offers the Semiconductor Industry the advantage of processing medium to high intensity implants on a system which will also implant 200 to 300 wafers an hour at MOS doses. Stable source beam currents can be varied over three orders of magnitude by variation of a single source parameter. This source uses a new computer designed Low Perveance extraction optics which is completely new to the Ion Implantation Industry. Test data and calculations are shown which define the versatility of this system. Scanned currents from 1 microamp to 400 microamps allow for a variety of production processing. Beam characteristics feature low energy spread (less than 10 eV) and low divergence (less than 3 degrees). Beam control optics consist of a double focusing analyzing magnet and two triplet quadrupoles. The source may be fitted with an oven for feeding of solid materials and analyzed beam currents in the milliamp range for development purposes. The batch processing, hybrid scanning end station is most applicable for high current beams as well as high volume batch processings of MOS Implants. Results of development work toward increased currents using both solid and gas feed material with the Low Perveance source are presented. System improvements including Accel-Decel and a third extraction element are discussed

  8. Profile of Low Vision Population Attending Low Vision Clinic in a Peripheral Eye Hospital in Nepal

    OpenAIRE

    Safal Khanal, BOptom; Pekila Lama, MD

    2013-01-01

    Background: Blindness and low vision are major causes of morbidity and constitute a significant public health problem, both detrimental to the quality of life for the individual and an economic burden on the individual, family, and society in general. People with low vision have the potential for enhancement of functional vision if they receive the appropriate low vision services. The present study aims to determine the profile of the low vision population attending a low vision clinic at a p...

  9. What You Should Know (Low Vision)

    Science.gov (United States)

    ... Cataract Diabetic retinopathy Glaucoma Macular degeneration What is low vision? When you have low vision, eyeglasses, contact lenses, ... eyesight. How do I know if I have low vision? Below are some signs of low vision. Even ...

  10. Low-Energy, Low-Cost Production of Ethylene by Low- Temperature Oxidative Coupling of Methane

    Energy Technology Data Exchange (ETDEWEB)

    Radaelli, Guido [Siluria Technologies, Inc., San Francisco, CA (United States); Chachra, Gaurav [Siluria Technologies, Inc., San Francisco, CA (United States); Jonnavittula, Divya [Siluria Technologies, Inc., San Francisco, CA (United States)

    2017-12-30

    In this project, we develop a catalytic process technology for distributed small-scale production of ethylene by oxidative coupling of methane at low temperatures using an advanced catalyst. The Low Temperature Oxidative Coupling of Methane (LT-OCM) catalyst system is enabled by a novel chemical catalyst and process pioneered by Siluria, at private expense, over the last six years. Herein, we develop the LT-OCM catalyst system for distributed small-scale production of ethylene by identifying and addressing necessary process schemes, unit operations and process parameters that limit the economic viability and mass penetration of this technology to manufacture ethylene at small-scales. The output of this program is process concepts for small-scale LT-OCM catalyst based ethylene production, lab-scale verification of the novel unit operations adopted in the proposed concept, and an analysis to validate the feasibility of the proposed concepts.

  11. Low back pain - acute

    Science.gov (United States)

    Backache; Low back pain; Lumbar pain; Pain - back; Acute back pain; Back pain - new; Back pain - short-term; Back strain - new ... lower back supports most of your body's weight. Low back pain is the number two reason that Americans see ...

  12. When Blood Sugar Is Too Low

    Science.gov (United States)

    ... Videos for Educators Search English Español When Blood Sugar Is Too Low KidsHealth / For Kids / When Blood ... get too low. The Causes of Low Blood Sugar Low blood sugar levels can happen to kids ...

  13. Could you have low testosterone?

    Science.gov (United States)

    ... by the testicles. It is important for a man's sex drive and physical appearance. Certain health conditions, medicines, or injury can lead to low testosterone (low-T). Testosterone level also naturally drops with age. Low testosterone can ... Testosterone makes a man look and feel like a man. In a ...

  14. Development of low-activation design method for reduction of radioactive waste (3). Various types of low-activation concrete

    International Nuclear Information System (INIS)

    Kinno, Masaharu; Kimura, Ken-ichi; Fujikura, Yusuke

    2008-01-01

    Manufacturing tests by mixing together with low-activation aggregates, low-activation cements, low-activation additives, low-activation admixtures and low-activation neutron absorbers have been performed to develop low-activation concrete. After that, we developed various types (1/10, 1/20, 1/30, 1/50, 1/100, 1/300, 1/1,000, 1/3,000 and 1/10,000) of low-activation concrete composed of low-activation raw materials as very useful shielding material in a nuclear facility. The term '1/10 of low-activation concrete' denotes that the activity reduction rate to ordinary concrete is designed to be 1/10. By adopting some suitable types of low-activation concrete, most of the shielding concrete around ABWR and APWR are classified below clearance level on decommissioning. (author)

  15. A Low-Complexity Euclidean Orthogonal LDPC Architecture for Low Power Applications.

    Science.gov (United States)

    Revathy, M; Saravanan, R

    2015-01-01

    Low-density parity-check (LDPC) codes have been implemented in latest digital video broadcasting, broadband wireless access (WiMax), and fourth generation of wireless standards. In this paper, we have proposed a high efficient low-density parity-check code (LDPC) decoder architecture for low power applications. This study also considers the design and analysis of check node and variable node units and Euclidean orthogonal generator in LDPC decoder architecture. The Euclidean orthogonal generator is used to reduce the error rate of the proposed LDPC architecture, which can be incorporated between check and variable node architecture. This proposed decoder design is synthesized on Xilinx 9.2i platform and simulated using Modelsim, which is targeted to 45 nm devices. Synthesis report proves that the proposed architecture greatly reduces the power consumption and hardware utilizations on comparing with different conventional architectures.

  16. A Low-Complexity Euclidean Orthogonal LDPC Architecture for Low Power Applications

    Directory of Open Access Journals (Sweden)

    M. Revathy

    2015-01-01

    Full Text Available Low-density parity-check (LDPC codes have been implemented in latest digital video broadcasting, broadband wireless access (WiMax, and fourth generation of wireless standards. In this paper, we have proposed a high efficient low-density parity-check code (LDPC decoder architecture for low power applications. This study also considers the design and analysis of check node and variable node units and Euclidean orthogonal generator in LDPC decoder architecture. The Euclidean orthogonal generator is used to reduce the error rate of the proposed LDPC architecture, which can be incorporated between check and variable node architecture. This proposed decoder design is synthesized on Xilinx 9.2i platform and simulated using Modelsim, which is targeted to 45 nm devices. Synthesis report proves that the proposed architecture greatly reduces the power consumption and hardware utilizations on comparing with different conventional architectures.

  17. Controlling low-rate signal path microdischarge for an ultra-low-background proportional counter

    International Nuclear Information System (INIS)

    Mace, E.K.; Aalseth, C.E.; Bonicalzi, R.M.; Day, A.R.; Hoppe, E.W.; Keillor, M.E.; Myers, A.W.; Overman, C.T.; Seifert, A.

    2013-01-01

    Pacific Northwest National Laboratory (PNNL) has developed an ultra-low-background proportional counter (ULBPC) made of high purity copper. These detectors are part of an ultra-low-background counting system (ULBCS) in the newly constructed shallow underground laboratory at PNNL (at a depth of ∼30 m water-equivalent). To control backgrounds, the current preamplifier electronics are located outside the ULBCS shielding. Thus the signal from the detector travels through ∼1 m of cable and is potentially susceptible to high voltage microdischarge and other sources of electronic noise. Based on initial successful tests, commercial cables and connectors were used for this critical signal path. Subsequent testing across different batches of commercial cables and connectors, however, showed unwanted (but still low) rates of microdischarge noise. To control this noise source, two approaches were pursued: first, to carefully validate cables, connectors, and other commercial components in this critical signal path, making modifications where necessary; second, to develop a custom low-noise, low-background preamplifier that can be integrated with the ULBPC and thus remove most commercial components from the critical signal path. This integrated preamplifier approach is based on the Amptek A250 low-noise charge-integrating preamplifier module. The initial microdischarge signals observed are presented and characterized according to the suspected source. Each of the approaches for mitigation is described, and the results from both are compared with each other and with the original performance seen with commercial cables and connectors. (author)

  18. Biological effects of low doses of radiation at low dose rate

    International Nuclear Information System (INIS)

    1996-05-01

    The purpose of this report was to examine available scientific data and models relevant to the hypothesis that induction of genetic changes and cancers by low doses of ionizing radiation at low dose rate is a stochastic process with no threshold or apparent threshold. Assessment of the effects of higher doses of radiation is based on a wealth of data from both humans and other organisms. 234 refs., 26 figs., 14 tabs

  19. Design and characterization of low-heat and low-alkalinity cements

    International Nuclear Information System (INIS)

    Codina, M.; Cau-dit-Coumes, C.; Le Bescop, P.; Verdier, J.; Ollivier, J.P.

    2008-01-01

    Investigations were carried out to formulate and characterize low-alkalinity and low-heat cements which would be compatible with an underground waste repository environment. Several systems comprising Portland cement, a pozzolan (silica fume or fly ash) and blastfurnace slag were compared. All blends were characterized by high amounts of additions, the Portland cement (PC) fraction ranging only from 20 to 60%. Cement hydration was studied using several techniques: X-ray Diffraction, TGA-DTA, calorimetry, pore solution extraction and microscopy. The most important result obtained with some ternary blends was the drop in the pore solution pH by more than one unit as compared with control samples elaborated with commercial cements. The alkali content (∼ 1 to 4 mmol/L) of the interstitial solution was also strongly reduced. The blends exhibited a low-heat output as required. Leaching tests carried out in pure water indicated a very slow decalcification of the samples. Several techniques such as optical microscopy, SEM/BSE, X-ray microanalysis or X-ray diffraction were compared to estimate the degraded thickness

  20. Impact of low vision services on the quality of life of low vision patients in Ghana

    Directory of Open Access Journals (Sweden)

    Godwin O. Ovenseri-Ogbomo

    2016-03-01

    Full Text Available Patients’ perspectives on the impact of clinical interventions have been recognised as critical elements in patient care. Quality-of-life instruments are designed to measure these perspectives. We used the National Eye Institute’s 25-item Visual Function Questionnaire (NEI VFQ to measure the impact of optical low vision devices on the quality of life of 22 low vision patients who obtained and were using low vision devices from a secondary low vision clinic in the Eastern Region, Ghana. The study employed a pre- and post-intervention technique. We found statistically significant improvements in measured visual acuity and NEI VFQ scores in 8 of the 10 domains evaluated. We conclude that optical low vision devices have a positive impact on the quality of life of low vision patients in Ghana. Keywords: low vision; quality of life; visual acuity; visual impairment; Ghana

  1. Factors affecting finite strain estimation in low-grade, low-strain clastic rocks

    Science.gov (United States)

    Pastor-Galán, Daniel; Gutiérrez-Alonso, Gabriel; Meere, Patrick A.; Mulchrone, Kieran F.

    2009-12-01

    The computer strain analysis methods SAPE, MRL and DTNNM have permitted the characterization of finite strain in two different regions with contrasting geodynamic scenarios; (1) the Talas Ala Tau (Tien Shan, Kyrgyzs Republic) and (2) the Somiedo Nappe and Narcea Antiform (Cantabrian to West Asturian-Leonese Zone boundary, Variscan Belt, NW of Iberia). The performed analyses have revealed low-strain values and the regional strain trend in both studied areas. This study also investigates the relationship between lithology (grain size and percentage of matrix) and strain estimates the two methodologies used. The results show that these methods are comparable and the absence of significant finite strain lithological control in rocks deformed under low metamorphic and low-strain conditions.

  2. Low frequency radioastronomy

    International Nuclear Information System (INIS)

    Zarka, Philippe; Cecconi, Baptiste; Tagger, Michel; Torchinsky, Steve; Picard, Philippe; Pezzani, Jacques; Cognard, Ismael; Boone, Frederic; Woan, Graham; Weber, Rodolphe; Gousset, Thierry; Lautridou, Pascal; Dallier, Richard

    2011-07-01

    Low frequency radioastronomy deals with the direct detection (below 100 MHz) and heterodyne detection (up to few GHz) of electromagnetic waves (phase and amplitude) followed by a time or spectral analysis. The 30. Goutelas school covered several aspects of radioastronomy involving various aspects of physics: non-thermal phenomena in plasmas and physics of magnetized plasmas, atomic and molecular physics, and particle physics. These proceedings comprise 17 lectures dealing with: 1 - Low-Frequency Radioastronomy Basics (P. Zarka); 2 - Radioastronomy Historical Highlights (S. A. Torchinsky); 3 - Antennas (P. Picard, J. Pezzani); 4 - Receptors (P. Picard, J. Pezzani); 5 - Pulsars chronometry: metrology in radioastronomy (I. Cognard); 6 - Interferometry as imaging technique (F. Boone); 7 - Radio propagation and scintillation (G. Woan); 8 - Square Kilometer Array (S. A. Torchinsky); 9 - Techniques against radio-electrical interferences in low-frequency radioastronomy (R. Weber); 10 - Introduction to poly-phase filtering (R. Weber); 11 - Three decades of Jupiter's radio-emission studies: from the Nancay deca-meter network to LOFAR (P. Zarka); 12 - Atmospheric showers and their radio counterpart (T. Gousset); 13 - From cosmic rays radio-detection to pulse radioastronomy (P. Lautridou, R. Dallier); 14 - The CODALEMA project (R. Dallier, P. Lautridou); 15 - Space-based radio measurements: Gonio-polarimetry (B. Cecconi); 16 - Radio astronomy from space (G. Woan); 17 - LOFAR: the Low Frequency Array and the French FLOW consortium (M. Tagger, P. Zarka)

  3. Contribution of low Birth –Weight and Very Low Birth Weight Infants ...

    African Journals Online (AJOL)

    Objective: To determine the association between low and very low birth weight infants and perinatal mortality at the University of Nigeria Teaching Hospital, Enugu. Methods: A retrospective study of the hospital records in the labour ward and the Newborn Special Care Unit (N.B.S.C.U), of the UNTH was carried out for the ...

  4. Low level waste repositories

    International Nuclear Information System (INIS)

    Hill, P.R.H.; Wilson, M.A.

    1983-11-01

    Factors in selecting a site for low-level radioactive waste disposal are discussed. South Australia has used a former tailings dam in a remote, arid location as a llw repository. There are also low-level waste disposal procedures at the Olympic Dam copper/uranium project

  5. Low Activity Microstates During Sleep.

    Science.gov (United States)

    Miyawaki, Hiroyuki; Billeh, Yazan N; Diba, Kamran

    2017-06-01

    To better understand the distinct activity patterns of the brain during sleep, we observed and investigated periods of diminished oscillatory and population spiking activity lasting for seconds during non-rapid eye movement (non-REM) sleep, which we call "LOW" activity sleep. We analyzed spiking and local field potential (LFP) activity of hippocampal CA1 region alongside neocortical electroencephalogram (EEG) and electromyogram (EMG) in 19 sessions from four male Long-Evans rats (260-360 g) during natural wake/sleep across the 24-hr cycle as well as data from other brain regions obtained from http://crcns.org.1,2. LOW states lasted longer than OFF/DOWN states and were distinguished by a subset of "LOW-active" cells. LOW activity sleep was preceded and followed by increased sharp-wave ripple activity. We also observed decreased slow-wave activity and sleep spindles in the hippocampal LFP and neocortical EEG upon LOW onset, with a partial rebound immediately after LOW. LOW states demonstrated activity patterns consistent with sleep but frequently transitioned into microarousals and showed EMG and LFP differences from small-amplitude irregular activity during quiet waking. Their likelihood decreased within individual non-REM epochs yet increased over the course of sleep. By analyzing data from the entorhinal cortex of rats,1 as well as the hippocampus, the medial prefrontal cortex, the postsubiculum, and the anterior thalamus of mice,2 obtained from http://crcns.org, we confirmed that LOW states corresponded to markedly diminished activity simultaneously in all of these regions. We propose that LOW states are an important microstate within non-REM sleep that provide respite from high-activity sleep and may serve a restorative function. © Sleep Research Society 2017. Published by Oxford University Press [on behalf of the Sleep Research Society].

  6. Mercury and selenium levels in 19 species of saltwater fish from New Jersey as a function of species, size, and season

    Science.gov (United States)

    Burger, Joanna; Gochfeld, Michael

    2014-01-01

    There are few data on risks to biota and humans from mercury levels in saltwater fish. This paper examines mercury and selenium levels in muscle of 19 species of fish caught by recreational fisherfolk off the New Jersey shore, as a function of species of fish, size, and season, and risk of mercury to consumers. Average mercury levels ranged from 0.01 ppm (wet weight) (Menhaden Brevoortia tyrannus) to 1.83 ppm (Mako Shark Isurus oxyrinchus). There were four categories of mercury levels: very high (only Mako), high (averaging 0.3–0.5 ppm, 3 species), medium (0.14–0.20 ppm, 10 species), and low (below 0.13 ppm, 5 species). Average selenium levels for the fish species ranged from 0.18 ppm to 0.58 ppm, and had lower variability than mercury (coefficient of variation=38.3 vs 69.1%), consistent with homeostatic regulation of this essential element. The correlation between mercury and selenium was significantly positive for five and negative for two species. Mercury levels showed significant positive correlations with fish size for ten species. Size was the best predictor of mercury levels. Selenium showed no consistent relationship to fish length. Over half of the fish species had some individual fish with mercury levels over 0.3 ppm, and a third had fish with levels over 0.5 ppm, levels that pose a human health risk for high end consumers. Conversely several fish species had no individuals above 0.5 ppm, and few above 0.3 ppm, suggesting that people who eat fish frequently, can reduce their risk from mercury by selecting which species (and which size) to consume. Overall, with the exception of shark, Bluefin Tuna (Thunnus thynnus), Bluefish (Pomatomus saltatrix) and Striped Bass (Morone saxatilis), the species sampled are generally medium to low in mercury concentration. Selenium:mercury molar ratios were generally above 1:1, except for the Mako shark. PMID:21292311

  7. Weekly and Twice-Weekly Yoga Classes Offer Similar Low-Back Pain Relief in Low-Income Minority Populations

    Science.gov (United States)

    ... Weekly and Twice-Weekly Yoga Classes Offer Similar Low-Back Pain Relief in Low-Income Minority Populations Share: © Photodisc ... in minority and low-income populations with chronic low-back pain. Researchers from Boston University School of Medicine, Boston ...

  8. Properties of low-fat, low-cholesterol egg yolk prepared by supercritical CO2 extraction.

    Science.gov (United States)

    Bringe, N A

    1997-01-01

    A dry egg yolk ingredient called Eggcellent has 74% less fat and 90% less cholesterol than liquid egg yolks, when reconstituted on an equal protein basis. The phospholipids and proteins are retained, enabling the ingredient to have the taste and texturizing properties of fresh egg yolk. Using the new yolk, it is possible to significantly improve the acceptability of low-fat, low-cholesterol bakery products, scrambled eggs and mayonnaise dressings without losing nutritional claims. The structures and functional properties of egg yolk components and the conditions required to optimize their benefits in foods are reviewed. The lipoproteins of low-fat, low-cholesterol yolk have valuable properties as flavorants, texturizers, foaming agents, emulsifiers, antioxidants, colorants, and nutraceuticals.

  9. Electrostatic fluctuations measured in low temperature helical plasmas with low collisionality

    International Nuclear Information System (INIS)

    Takeuchi, M.; Ikeda, R.; Ito, T.; Toi, K.; Suzuki, C.; Matsunaga, G.

    2004-01-01

    Electrostatic fluctuations have been measured by Langmuir probes from edge to core plasma region in low temperature helical plasmas which are produced by 2.45 GHz microwaves at very low field less than 0.1 T. The principal dimensionless parameters of the plasmas, that is, the normalized electron-ion collision frequency ν ei , and averaged plasma β φ and others are in the same range of them in high temperature plasmas, except the normalized gyro radius ρ s . The data on fluctuation characteristics from the dimensionally similar low temperature plasmas may give an important insight into the understanding of turbulent transport in high temperature plasmas. Dependences of fluctuation amplitudes on the radial electric field shear, ρ s and ν ei are investigated. Electrostatic fluctuations propagating in electron-diamagnetic drift direction have been observed in the plasma edge region and in ion-diamagnetic drift direction in the plasma core region. (authors)

  10. Formulating a low-alkalinity, high-resistance and low-heat concrete for radioactive waste repositories

    International Nuclear Information System (INIS)

    Cau Dit Coumes, Celine; Courtois, Simone; Nectoux, Didier; Leclercq, Stephanie; Bourbon, Xavier

    2006-01-01

    Investigations were carried out in order to formulate and characterize low-alkalinity and low-heat cements which would be compatible with an underground waste repository environment. Several systems comprising Ordinary Portland Cement (OPC), a fast-reacting pozzolan (silica fume (SF) or metakaolin (MK)) and, in some cases, a slow-reacting product (fly ash (FA) or blastfurnace slag (BFS)) were compared. Promising results were obtained with some binary mixtures of OPC and SF, and with some ternary blends of OPC, SF and FA or BFS: pH of water in equilibrium with the fully hydrated cements dropped below 11. Dependence of the properties of standard mortars on the high contents of FA and SF in the low-pH blends was examined. Combining SF and FA seemed attractive since SF compensated for the low reactivity of FA, while FA allowed to reduce the water demand, and dimensional variations of the mortars. Finally, low-heat (ΔT < 20 deg. C under semi-adiabatic conditions) and high strength (∼ 70-80 MPa) concretes were prepared from two low-pH cements: a binary blend made from 60% of OPC and 40% of SF, and a ternary blend including 37.5% OPC, 32.5% SF and 30% FA

  11. Defining Abnormally Low Tenders

    DEFF Research Database (Denmark)

    Ølykke, Grith Skovgaard; Nyström, Johan

    2017-01-01

    The concept of an abnormally low tender is not defined in EU public procurement law. This article takes an interdisciplinary law and economics approach to examine a dataset consisting of Swedish and Danish judgments and verdicts concerning the concept of an abnormally low tender. The purpose...

  12. Development of combined low-emissions burner devices for low-power boilers

    Science.gov (United States)

    Roslyakov, P. V.; Proskurin, Yu. V.; Khokhlov, D. A.

    2017-08-01

    Low-power water boilers are widely used for autonomous heat supply in various industries. Firetube and water-tube boilers of domestic and foreign manufacturers are widely represented on the Russian market. However, even Russian boilers are supplied with licensed foreign burner devices, which reduce their competitiveness and complicate operating conditions. A task of developing efficient domestic low-emissions burner devices for low-power boilers is quite acute. A characteristic property of ignition and fuel combustion in such boilers is their flowing in constrained conditions due to small dimensions of combustion chambers and flame tubes. These processes differ significantly from those in open combustion chambers of high-duty power boilers, and they have not been sufficiently studied yet. The goals of this paper are studying the processes of ignition and combustion of gaseous and liquid fuels, heat and mass transfer and NO x emissions in constrained conditions, and the development of a modern combined low-emissions 2.2 MW burner device that provides efficient fuel combustion. A burner device computer model is developed and numerical studies of its operation on different types of fuel in a working load range from 40 to 100% of the nominal are carried out. The main features of ignition and combustion of gaseous and liquid fuels in constrained conditions of the flame tube at nominal and decreased loads are determined, which differ fundamentally from the similar processes in steam boiler furnaces. The influence of the burner devices design and operating conditions on the fuel underburning and NO x formation is determined. Based on the results of the design studies, a design of the new combined low-emissions burner device is proposed, which has several advantages over the prototype.

  13. Low Transvalvular Flow Rate Predicts Mortality in Patients With Low-Gradient Aortic Stenosis Following Aortic Valve Intervention.

    Science.gov (United States)

    Vamvakidou, Anastasia; Jin, Wenying; Danylenko, Oleksandr; Chahal, Navtej; Khattar, Rajdeep; Senior, Roxy

    2018-03-09

    This study aimed to assess the value of low transvalvular flow rate (FR) for the prediction of mortality compared with low stroke volume index (SVi) in patients with low-gradient (mean gradient: gradient AS who had undergone valve intervention. We retrospectively followed prospectively assessed consecutive patients with low-gradient, low aortic valve area AS who underwent aortic valve intervention between 2010 and 2014 for all-cause mortality. Of the 218 patients with mean age 75 ± 12 years, 102 (46.8%) had low stroke volume index (SVi) (gradient, low valve area aortic stenosis undergoing aortic valve intervention, low FR, not low SVi, was an independent predictor of medium-term mortality. Copyright © 2018 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  14. Packaged low-level waste verification system

    Energy Technology Data Exchange (ETDEWEB)

    Tuite, K.; Winberg, M.R.; McIsaac, C.V. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1995-12-31

    The Department of Energy through the National Low-Level Waste Management Program and WMG Inc. have entered into a joint development effort to design, build, and demonstrate the Packaged Low-Level Waste Verification System. Currently, states and low-level radioactive waste disposal site operators have no method to independently verify the radionuclide content of packaged low-level waste that arrives at disposal sites for disposition. At this time, the disposal site relies on the low-level waste generator shipping manifests and accompanying records to ensure that low-level waste received meets the site`s waste acceptance criteria. The subject invention provides the equipment, software, and methods to enable the independent verification of low-level waste shipping records to ensure that the site`s waste acceptance criteria are being met. The objective of the prototype system is to demonstrate a mobile system capable of independently verifying the content of packaged low-level waste.

  15. Low-cost high purity production

    Science.gov (United States)

    Kapur, V. K.

    1978-01-01

    Economical process produces high-purity silicon crystals suitable for use in solar cells. Reaction is strongly exothermic and can be initiated at relatively low temperature, making it potentially suitable for development into low-cost commercial process. Important advantages include exothermic character and comparatively low process temperatures. These could lead to significant savings in equipment and energy costs.

  16. Low power arcjet performance

    Science.gov (United States)

    Curran, Francis M.; Sarmiento, Charles J.

    1990-01-01

    An experimental investigation was performed to evaluate arcjet operation at low power. A standard, 1 kW, constricted arcjet was run using nozzles with three different constrictor diameters. Each nozzle was run over a range of current and mass flow rates to explore stability and performance in the low power regime. A standard pulse-width modulated power processor was modified to accommodate the high operating voltages required under certain conditions. Stable, reliable operation at power levels below 0.5 kW was obtained at efficiencies between 30 and 40 percent. The operating range was found to be somewhat dependent on constrictor geometry at low mass flow rates. Quasi-periodic voltage fluctuations were observed at the low power end of the operating envelope. The nozzle insert geometry was found to have little effect on the performance of the device. The observed performance levels show that specific impulse levels above 350 seconds can be obtained at the 0.5 kW power level.

  17. How many low birthweight babies in low- and middle-income countries are preterm?

    Directory of Open Access Journals (Sweden)

    Fernando C Barros

    2011-06-01

    Full Text Available OBJECTIVE: To assess the prevalence of preterm birth among low birthweight babies in low and middle-income countries. METHODS: Major databases (PubMed, LILACS, Google Scholar were searched for studies on the prevalence of term and preterm LBW babies with field work carried out after 1990 in low- and middle-income countries. Regression methods were used to model this proportion according to LBW prevalence levels. RESULTS: According to 47 studies from 27 low- and middle-income countries, approximately half of all LBW babies are preterm rather than one in three as assumed in studies previous to the 1990s. CONCLUSIONS: The estimate of a substantially higher number of LBW preterm babies has important policy implications in view of special health care needs of these infants. As for earlier projections, our findings are limited by the relative lack of population-based studies.

  18. ANALISIS PERIKANAN HUHATE DI PERAIRAN LARANTUKA, FLORES

    Directory of Open Access Journals (Sweden)

    Mohamad Adha Akbar

    2016-11-01

    Full Text Available Informasi mengenai beberapa aspek perikanan huhate sangat diperlukan sebagai bahan untuk perencanaan pengelolaan perikanan yang berkelanjutan. Penelitian ini dilakukan di Larantuka, Flores Timur pada tahun 2014 dengan tujuan untuk menganalisis perikanan huhate sebagai salah satu tulang punggung perikanan TCT. Kegiatan penelitian diprioritaskan pada analisis unit alat tangkap, daerah penangkapan, komposisi hasil tangkapan dan estimasi Total Faktor Produktivitas (TFP perikanan huhate. Basis data pengukuran adalah himpunan  data pendaratan dan observasi lapang. Hasil penelitian menunjukan bahwa karakteristik armada terdiri dari kapal yang terbuat dari fibreglass dengan kisaran bobot kapal 6 - 30 GT. Daerah penangkapan di sekitar perairan Laut Sawu dan Laut Flores. Hasil tangkapan utama didominansi oleh cakalang (Katsuwonus pelamis sebanyak 82%, juwana tuna (Thunnus spp. 17% dan tongkol (Auxis spp. 1% serta hasil tangkapan ikutan lemadang (Coryphaena hippurus dan marlin (Makaira spp. < 1%. Hasil analisis tangkapan per unit upaya (CPUE memberikan nilai rata-rata sebesar 1,1 ton/trip (0,4-1,7 ton/trip dengan nilai tertinggi terjadi pada Februari, sedangkan terendah terjadi pada Januari. Hasil penelitian menunjukkan terdapat hubungan yang signifikan antara tren bulanan CPUE dan nilai TFP.

  19. [Fatty acid variation in yellowfin tuna, spotted weakfish and Florida pompano when submitted to six cooking techniques].

    Science.gov (United States)

    Castro-González, María Isabel; Maafs-Rodríguez, Ana Gabriela; Romo Pérez-Gil, Fernando

    2013-03-01

    The aim of the present study was to analyze the effect of six cooking techniques (steamed, foiled, foiled with banana leaf, baked, microwave-cooked and light frying) in the fatty acid content of Thunnus albacore (yellowfin tuna), Cynoscionnebulosus (spotted weakfish) and Trachinotuscarolinus (Florida pompano). After cooking the fish fillets, fatty acid analyses were performed using gas chromatography. Total lipids increased in all cooking techniques in tunaand spotted weakfish. Saturated fatty acids of tuna and spotted weakfish increased in three cooking techniques, while in Florida pompano only gas oven raised their content. Lightly frying generated the highest content of n-3 in tuna and spotted weakfish, and the lowest in Florida pompano, specie that presented less variation. In tuna fish, the most recommended cooking techniques are foiled with aluminum and microwave oven; for spotted weakfish, foiled with banana leaf; while Florida pompano can be prepared using all cooking methods except gas oven. This information is useful to enrich data from chemical composition tables, in which concentrations are usually presented in raw food.

  20. Trajectories of low back pain

    DEFF Research Database (Denmark)

    Axén, Iben; Leboeuf-Yde, Charlotte

    2013-01-01

    Low back pain is not a self-limiting problem, but rather a recurrent and sometimes persistent disorder. To understand the course over time, detailed investigation, preferably using repeated measurements over extended periods of time, is needed. New knowledge concerning short-term trajectories...... indicates that the low back pain 'episode' is short lived, at least in the primary care setting, with most patients improving. Nevertheless, in the long term, low back pain often runs a persistent course with around two-thirds of patients estimated to be in pain after 12 months. Some individuals never have...... low back pain, but most have it on and off or persistently. Thus, the low back pain 'condition' is usually a lifelong experience. However, subgroups of patients with different back pain trajectories have been identified and linked to clinical parameters. Further investigation is warranted...

  1. Evolution of low-temperature phases in a low-temperature structural transition of a La cuprate

    International Nuclear Information System (INIS)

    Inoue, Y.; Horibe, Y.; Koyama, Y.

    1997-01-01

    The microstructure produced by a low-temperature structural phase transition in La 1.5 Nd 0.4 Sr 0.1 CuO 4 has been examined by transmission electron microscopy with the help of imaging plates. The low-temperature transition was found to be proceeded not only by the growth of the Pccn/low-temperature-tetragonal phases nucleated along the twin boundary but also by the nucleation and growth of the phases in the interior of the low-temperature-orthorhombic domain. In addition, because the map of the octahedron tilt as an order parameter is not identical to that of the spontaneous strain accompanied by the transition, the microstructure below the transition is understood to be a very complex mixture of the low-temperature phases. copyright 1997 The American Physical Society

  2. The marketing of testosterone treatments for age-related low testosterone or 'Low T'.

    Science.gov (United States)

    Mintzes, Barbara

    2018-06-01

    To summarize the research evidence on promotion of testosterone for 'Low T', or age-related hypogonadism. Marketing of testosterone for 'Low T' has relied on strategies that are inadequately regulated to prevent off-label promotion, such as unbranded 'disease-awareness' advertising campaigns targeting the general public, sponsored continuing medical education (CME) and ghostwriting. A recent US analysis of television advertising exposure levels versus insurance claims found that both unbranded 'disease-awareness' advertising and branded ads were associated with increased rates of testosterone testing, treatment initiation, and treatment without prior testing. Exposés of sponsored CME and ghostwriting indicate misrepresentation of the research evidence on the sequelae of untreated low testosterone and on treatment efficacy. In the United States, advertising to the general public ceased in 2014 after the Food and Drug Administration changed product labeling to clarify that testosterone is only indicated for pathological hypogonadism. Unbranded 'disease-awareness' advertising to the general public and 'Low T' messages for health professionals have continued elsewhere. The review of the experience of promotion of testosterone for 'Low T' and research evidence on effects of advertising targeting the public highlights the need for improved regulation of unbranded 'disease awareness' advertising to ensure adequate protection of public.

  3. Low-Wage Counties Face Locational Disadvantages.

    Science.gov (United States)

    Gibbs, Robert; Cromartie, John B.

    2000-01-01

    Small populations and remoteness are the most salient features of low-wage counties. These locational attributes coincide with fewer high-wage jobs, yet low wages within industries define low-wage counties more than industry composition. Although adults in low-wage counties have less education and labor force participation overall, the role played…

  4. Constituent attachment and voluntary turnover in low-wage/low-skill service work.

    Science.gov (United States)

    Ellingson, Jill E; Tews, Michael J; Dachner, Alison M

    2016-01-01

    This paper draws on life stage theory, ethnographic research conducted in the service sector, and evidence for secondary segmentation within the low-wage/low-skill labor force to offer evidence that social bond development with coworkers can help reduce the high rate of turnover observed in low-wage/low-skill service work. Contrary to the belief that these employees will leave before social ties can develop, constituent attachment was found to be the only significant predictor of turnover in 2 samples of front-line service workers in a casual dining, national restaurant chain after controlling for other aspects of work that can create a sense of attachment to a job, and other job attitudes, such as satisfaction and commitment. However, the effect was dependent on developmental life stage. Constituent attachment reduced turnover among workers classified as emerging adults, whereas constituent attachment did little to affect turnover among nonemerging adults. Implications of the results are discussed with respect to the value of considering segmentation in future research on turnover in the service sector and the use of life stage theory for understanding the leaving behavior of workers in different stages of adulthood. (c) 2016 APA, all rights reserved).

  5. GIS-aided low flow mapping

    Science.gov (United States)

    Saghafian, B.; Mohammadi, A.

    2003-04-01

    Most studies involving water resources allocation, water quality, hydropower generation, and allowable water withdrawal and transfer require estimation of low flows. Normally, frequency analysis on at-station D-day low flow data is performed to derive various T-yr return period values. However, this analysis is restricted to the location of hydrometric stations where the flow discharge is measured. Regional analysis is therefore conducted to relate the at-station low flow quantiles to watershed characteristics. This enables the transposition of low flow quantiles to ungauged sites. Nevertheless, a procedure to map the regional regression relations for the entire stream network, within the bounds of the relations, is particularly helpful when one studies and weighs alternative sites for certain water resources project. In this study, we used a GIS-aided procedure for low flow mapping in Gilan province, part of northern region in Iran. Gilan enjoys a humid climate with an average of 1100 mm annual precipitation. Although rich in water resources, the highly populated area is quite dependent on minimum amount of water to sustain the vast rice farming and to maintain required flow discharge for quality purposes. To carry out the low flow analysis, a total of 36 hydrometric stations with sufficient and reliable discharge data were identified in the region. The average area of the watersheds was 250 sq. km. Log Pearson type 3 was found the best distribution for flow durations over 60 days, while log normal fitted well the shorter duration series. Low flows with return periods of 2, 5, 10, 25, 50, and 100 year were then computed. Cluster analysis identified two homogeneous areas. Although various watershed parameters were examined in factor analysis, the results showed watershed area, length of the main stream, and annual precipitation were the most effective low flow parameters. The regression equations were then mapped with the aid of GIS based on flow accumulation maps

  6. Boron, arsenic and phosphorus dopant incorporation during low temperature low pressure silicon epitaxial growth

    International Nuclear Information System (INIS)

    Borland, J.O.; Thompson, T.; Tagle, V.; Benzing, W.

    1987-01-01

    Submicron silicon epitaxial structures with very abrupt epi/substrate transition widths have been realized through the use of low temperature silicon epitaxial growth techniques. At these low temperature and low pressure epitaxial growth conditions there is minimal, if any, dopant diffusion from the substrate into the epilayer during deposition. The reincorporation of autodoped dopant as well as the incorporation of intentional dopant can be a trade-off at low temperatures and low pressures. For advanced CMOS and Bi-CMOS technologies, five to six orders of magnitude change in concentration levels are desirable. In this investigation, all of the epitaxial depositions were carried out in an AMC-7810 epi-reactor with standard jets for a turbulent mixing system, and using a modified center inject configuration to achieve a single pass laminar flow system. To simulate the reincorporation of various autodoped dopant, the authors ran a controlled dopant flow of 100 sccm for each of the three dopants (boron, phosphorus and arsenic) to achieve the controlled background dopant level in the reactor gas stream

  7. Development of a low cost, low temperature cryocooler using the Gifford McMahon cycle

    Science.gov (United States)

    Ramanayaka, A.; Mani, R.

    2008-03-01

    Although Helium is the second most abundant element, its concentration in the earth's atmosphere is fairly low and constant, as the portion that escapes from the atmosphere is replace by new emission. Historically, Helium was extracted as a byproduct of natural gas production, and stored in gas fields in a National Helium Reserve, in an attempt to conserve this interesting element. National policy has changed and the cost of liquid Helium has increased rapidly in the recent past. These new circumstances have created new interest in alternative eco-friendly methods to realizing and maintaining low temperatures in the laboratory. There have been number of successful attempts at making low temperature closed cycle Helium refrigerators by modifying an existing closed cycle system, and usually the regenerator has been replaced in order to achieve the desired results. Here, we discus our attempt to fabricate a low cost, low temperature closed cycle Helium refrigerator starting from a 15K Gifford McMahon system. We reexamine the barriers to realizing lower temperature here and our attempts at overcoming them.

  8. Low Duty-Cycling MAC Protocol for Low Data-Rate Medical Wireless Body Area Networks

    Directory of Open Access Journals (Sweden)

    Chongqing Zhang

    2017-05-01

    Full Text Available Wireless body area networks (WBANs are severely energy constrained, and how to improve the energy efficiency so as to prolong the network lifetime as long as possible is one of the most important goals of WBAN research. Low data-rate WBANs are promising to cut down the energy consumption and extend the network lifetime. Considering the characteristics and demands of low data-rate WBANs, a low duty-cycling medium access control (MAC protocol is specially designed for this kind of WBAN in this paper. Longer superframes are exploited to cut down the energy consumed on the transmissions and receptions of redundant beacon frames. Insertion time slots are embedded into the inactive part of a superframe to deliver the frames and satisfy the quality of service (QoS requirements. The number of the data subsections in an insertion time slot can be adaptively adjusted so as to accommodate low data-rate WBANs with different traffic. Simulation results show that the proposed MAC protocol performs well under the condition of low data-rate monitoring traffic.

  9. Low-Dose-Rate Brachytherapy Versus Cryotherapy in Low- and Intermediate-Risk Prostate Cancer.

    Science.gov (United States)

    Gestaut, Matthew M; Cai, Wendi; Vyas, Shilpa; Patel, Belur J; Hasan, Salman A; MunozMaldonado, Yolanda; Deb, Niloyjyoti; Swanson, Gregory

    2017-05-01

    Cryotherapy and brachytherapy are definitive local treatment options for low- to intermediate-risk prostate cancer. There are both prospective and retrospective data for brachytherapy, but the use of cryotherapy has been limited primarily to single-institution retrospective studies. Currently, no published evidence has compared low-dose-rate brachytherapy versus cryotherapy. Institutional review board approval was obtained to conduct a retrospective chart review of consecutive patients treated at our institution from 1990 to 2012. For inclusion, patients must have received a prostate cancer diagnosis and have been considered to have low- to intermediate-risk disease according to the National Comprehensive Cancer Network criteria. All patients received brachytherapy or cryotherapy treatment. Disease specifics and failure details were collected for all patients. Failure was defined as prostate-specific antigen nadir +2 ng/mL. A total of 359 patients were analyzed. The groups comprised 50 low-risk cryotherapy (LRC), 92 intermediate-risk cryotherapy (IRC), 133 low-risk brachytherapy (LRB), and 84 intermediate-risk brachytherapy (IRB) patients. The median prostate-specific antigen follow-up periods were 85.6 months (LRC), 59.2 months (IRC), 74.9 months (LRB), and 59.8 months (IRB). The 5-year biochemical progression-free survival (bPFS) rate was 57.9% in the cryotherapy group versus 89.6% in the brachytherapy group (Pcryotherapy for low- and intermediate-risk groups (Pcryotherapy patients was -35°C (range, -96°C to -6°C). Cryotherapy used a median of 2 freeze-thaw cycles (range, 2-4 freeze-thaw cycles). Results from this study suggest that cryotherapy is inferior to brachytherapy for patients with low- to intermediate-risk prostate cancer. Patient selection criteria for consideration of cryotherapy and brachytherapy are similar in terms of anesthesia candidacy. Therefore, cryotherapy would not be recommended as a first-line local therapy for this particular

  10. Voluntary low-force contraction elicits prolonged low-frequency fatigue and changes in surface electromyography and mechanomyography

    DEFF Research Database (Denmark)

    Blangsted, Anne Katrine; Sjøgaard, Gisela; Madeleine, Pascal

    2005-01-01

    Controversies exist regarding objective documentation of fatigue development with low-force contractions. We hypothesized that non-exhaustive, low-force muscle contraction may induce prolonged low-frequency fatigue (LFF) that in the subsequent recovery period is detectable by electromyography (EMG...

  11. Low-Wage Work in Denmark

    DEFF Research Database (Denmark)

    Westergård-Nielsen, Niels Chr.

    2008-01-01

    not stay in low-wage jobs for long. Many go on to higher paying jobs, while a significant minority ends up relying temporarily on income support and benefits sustained by one of the highest tax rates in the world.  Low-Wage Work in Denmark provides an insightful look at the particularities of the Danish...... with detailed case studies of five industries to explore why low-end jobs are so different in Denmark. Some jobs that are low-paying in the United States, including hotel maids and meat processors, though still demanding, are much more highly compensated in Denmark. And Danes, unlike American workers, do...

  12. Trophic ecology of Atlantic Bluefin Tuna (Thunnus thynnus [corrected] larvae from the Gulf of Mexico and NW Mediterranean spawning grounds: A Comparative Stable Isotope Study.

    Directory of Open Access Journals (Sweden)

    Raúl Laiz-Carrión

    Full Text Available The present study uses stable isotopes of nitrogen and carbon (δ15Nandδ13C as trophic indicators for Atlantic bluefin tuna larvae (BFT (6-10 mm standard length in the highly contrasting environmental conditions of the Gulf of Mexico (GOM and the Balearic Sea (MED. These regions are differentiated by their temperature regime and relative productivity, with the GOM being significantly warmer and more productive. MED BFT larvae showed the highest δ15N signatures, implying an elevated trophic position above the underlying microzooplankton baseline. Ontogenetic dietary shifts were observed in the BFT larvae from the GOM and MED which indicates early life trophodynamics differences between these spawning habitats. Significant trophic differences between the GOM and MED larvae were observed in relation to δ15N signatures in favour of the MED larvae, which may have important implications in their growth during their early life stages.These low δ15N levels in the zooplankton from the GOM may be an indication of a shifting isotopic baseline in pelagic food webs due to diatrophic inputs by cyanobacteria. Lack of enrichment for δ15N in BFT larvae compared to zooplankton implies an alternative grazing pathway from the traditional food chain of phytoplankton-zooplankton-larval fish. Results provide insight for a comparative characterization of the trophic pathways variability of the two main spawning grounds for BFT larvae.

  13. A low-carbohydrate, ketogenic diet versus a low-fat diet to treat obesity and hyperlipidemia: a randomized, controlled trial.

    Science.gov (United States)

    Yancy, William S; Olsen, Maren K; Guyton, John R; Bakst, Ronna P; Westman, Eric C

    2004-05-18

    Low-carbohydrate diets remain popular despite a paucity of scientific evidence on their effectiveness. To compare the effects of a low-carbohydrate, ketogenic diet program with those of a low-fat, low-cholesterol, reduced-calorie diet. Randomized, controlled trial. Outpatient research clinic. 120 overweight, hyperlipidemic volunteers from the community. Low-carbohydrate diet (initially, carbohydrate daily) plus nutritional supplementation, exercise recommendation, and group meetings, or low-fat diet (fat, low-carbohydrate diet group than the low-fat diet group completed the study (76% vs. 57%; P = 0.02). At 24 weeks, weight loss was greater in the low-carbohydrate diet group than in the low-fat diet group (mean change, -12.9% vs. -6.7%; P fat mass (change, -9.4 kg with the low-carbohydrate diet vs. -4.8 kg with the low-fat diet) than fat-free mass (change, -3.3 kg vs. -2.4 kg, respectively). Compared with recipients of the low-fat diet, recipients of the low-carbohydrate diet had greater decreases in serum triglyceride levels (change, -0.84 mmol/L vs. -0.31 mmol/L [-74.2 mg/dL vs. -27.9 mg/dL]; P = 0.004) and greater increases in high-density lipoprotein cholesterol levels (0.14 mmol/L vs. -0.04 mmol/L [5.5 mg/dL vs. -1.6 mg/dL]; P low-density lipoprotein cholesterol level did not differ statistically (0.04 mmol/L [1.6 mg/dL] with the low-carbohydrate diet and -0.19 mmol/L [-7.4 mg/dL] with the low-fat diet; P = 0.2). Minor adverse effects were more frequent in the low-carbohydrate diet group. We could not definitively distinguish effects of the low-carbohydrate diet and those of the nutritional supplements provided only to that group. In addition, participants were healthy and were followed for only 24 weeks. These factors limit the generalizability of the study results. Compared with a low-fat diet, a low-carbohydrate diet program had better participant retention and greater weight loss. During active weight loss, serum triglyceride levels decreased more and high

  14. Termite mounds harness diurnal temperature oscillations for ventilation.

    Science.gov (United States)

    King, Hunter; Ocko, Samuel; Mahadevan, L

    2015-09-15

    Many species of millimetric fungus-harvesting termites collectively build uninhabited, massive mound structures enclosing a network of broad tunnels that protrude from the ground meters above their subterranean nests. It is widely accepted that the purpose of these mounds is to give the colony a controlled microclimate in which to raise fungus and brood by managing heat, humidity, and respiratory gas exchange. Although different hypotheses such as steady and fluctuating external wind and internal metabolic heating have been proposed for ventilating the mound, the absence of direct in situ measurement of internal air flows has precluded a definitive mechanism for this critical physiological function. By measuring diurnal variations in flow through the surface conduits of the mounds of the species Odontotermes obesus, we show that a simple combination of geometry, heterogeneous thermal mass, and porosity allows the mounds to use diurnal ambient temperature oscillations for ventilation. In particular, the thin outer flutelike conduits heat up rapidly during the day relative to the deeper chimneys, pushing air up the flutes and down the chimney in a closed convection cell, with the converse situation at night. These cyclic flows in the mound flush out CO2 from the nest and ventilate the colony, in an unusual example of deriving useful work from thermal oscillations.

  15. Reducing the Incidence of Low Birth Weight in Low-Income Countries Has Substantial Economic Benefits

    OpenAIRE

    Alderman, Harold; Behrman, Jere R.

    2006-01-01

    Reducing the incidence of low birth weight not only lowers infant mortality rates but also has multiple benefits over the life cycle. This study estimates the economic benefits of reducing the incidence of low birth weight in low-income countries, both through lower mortality rates and medical costs and through increased learning and productivity. The estimated economic benefits, under pla...

  16. Differential effects of low-carbohydrate and low-fat diets on inflammation and endothelial function in diabetes.

    Science.gov (United States)

    Davis, Nichola J; Crandall, Jill P; Gajavelli, Srikanth; Berman, Joan W; Tomuta, Nora; Wylie-Rosett, Judith; Katz, Stuart D

    2011-01-01

    To characterize acute (postprandial) and chronic (after a 6-month period of weight loss) effects of a low-carbohydrate vs. a low-fat diet on subclinical markers of cardiovascular disease (CVD) in adults with type 2 diabetes. At baseline and 6 months, measures of C-reactive protein (CRP), interleukin-6 (IL-6), soluble intercellular adhesion molecule (sICAM) and soluble E-selectin were obtained from archived samples (n = 51) of participants randomized in a clinical trial comparing a low-carbohydrate and a low-fat diet. In a subset of participants (n = 27), postprandial measures of these markers were obtained 3 h after a low-carbohydrate or low-fat liquid meal. Endothelial function was also measured by reactive hyperemic peripheral arterial tonometry during the meal test. Paired t tests and unpaired t tests compared within- and between-group changes. There were no significant differences observed in postprandial measures of inflammation or endothelial function. After 6 months, CRP (mean ± S.E.) decreased in the low-fat arm from 4.0 ± 0.77 to 3.0 ± 0.77 (P = .01). In the low-carbohydrate arm, sICAM decreased from 234 ± 22 to 199 ± 23 (P = .001), and soluble E-selectin decreased from 93 ± 10 to 82 ± 10 (P = .05.) A significant correlation between change in high-density lipoprotein and change in soluble E-selectin (r = -0.33, P = .04) and with the change in ICAM (r = -0.43, P = .01) was observed. Low-carbohydrate and low-fat diets both have beneficial effects on CVD markers. There may be different mechanisms through which weight loss with these diets potentially reduces CVD risk. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Social causes of low birth weight.

    OpenAIRE

    Kogan, M D

    1995-01-01

    The manifest importance of reducing the incidence of low birth weight is most obvious for the first year of life: low birth weight is the single most important factor affecting infant morbidity and mortality. However, there is growing evidence that the adverse consequences of low birth weight continue throughout the life cycle. This review deals primarily with social causes of low birth weight.

  18. Low dose epidemiologic studies

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    In this chapter the BEIR committee has reviewed low-dose irradiation studies since the BEIR III report. They have considered the carcinogenic effectiveness of low-LET in populations exposed to radiation from a number of different sources: diagnostic radiography; fallout from nuclear weapons testing; nuclear installations; radiation in the workplace and high levels of natural background radiation

  19. Barriers to accessing low vision services.

    Science.gov (United States)

    Pollard, Tamara L; Simpson, John A; Lamoureux, Ecosse L; Keeffe, Jill E

    2003-07-01

    To investigate barriers to accessing low vision services in Australia. Adults with a vision impairment (vision difficulties, duration of vision loss and satisfaction with vision and also examined issues of awareness of low vision services and referral to services. Focus groups were also conducted with vision impaired (Vision Australia Foundation. The discussions were recorded and transcribed. The questionnaire revealed that referral to low vision services was associated with a greater degree of vision loss (p = 0.002) and a greater self-perception of low vision (p = 0.005) but that referral was not associated with satisfaction (p = 0.144) or difficulties related to vision (p = 0.169). Participants with mild and moderate vision impairment each reported similar levels of difficulties with daily activities and satisfaction with their vision (p > 0.05). However, there was a significant difference in the level of difficulties experienced with daily activities between those with mild-moderate and severe vision impairment (p low vision services related to awareness of services among the general public and eye care professionals, understanding of low vision and the services available, acceptance of low vision, the referral process, and transport. In addition to the expected difficulties with lack of awareness of services by people with low vision, many people do not understand what the services provide and do not identify themselves as having low vision. Knowledge of these barriers, from the perspective of people with low vision, can now be used to guide the development and content of future health-promotion campaigns.

  20. Low background infrared (LBIR) facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Low background infrared (LBIR) facility was originally designed to calibrate user supplied blackbody sources and to characterize low-background IR detectors and...

  1. Electro-Optics/Low Observables Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Electro-Optics/Low Observables Laboratory supports graduate instruction for students enrolled in the Low Observables program. Its purpose is to introduce these...

  2. Low-level-waste-treatment handbook

    International Nuclear Information System (INIS)

    Clinton, S.D.; Goeller, H.E.; Holladay, D.W.; Donaldson, T.L.

    1982-01-01

    The initial draft of the Low-Level Waste Treatment Handbook has been prepared and submitted to the DOE Low-Level Waste Management Program for review and comment. A revised draft is scheduled to be delivered to DOE Headquarters in December 1982. The Handbook is designed to be useful to all individuals and groups concerned with low-level wastes. It is one of several volumes that will ultimately comprise a Low-Level Waste Technology Handbook. The objective of the Low-Level Waste Treatment Handbook is to present an overview of current practices related to the segregation, classification, volume reduction, solidification, handling, packaging, and transportation of LLW for disposal in a shallow land burial facility. The Handbook is intended to serve as a guide to individuals interested in the treatment and handling of low-level radioactive waste. The Handbook will not explicitly tell the user how to design and operate LLW treatment facilities, but rather will identify (1) kinds of information required to evaluate the options, (2) methods that may be used to evaluate these options, and (3) limitations associated with the selection of the treatment options. The focus of the Handbook is providing guidance on how to do waste treatment for disposal by shallow land burial

  3. The Problem: Low-Achieving Districts and Low-Performing Boards

    Directory of Open Access Journals (Sweden)

    David E. Lee

    2014-10-01

    Full Text Available Effective school districts maintain superintendent and school board collegiality which can foster success and connectedness among members. Delagardelle and Alsbury (2008 found that superintendents and board members are not consistent in their perceptions about the work the board does, and Glass (2007 found that states do not require boards to undergo evaluation for effectiveness. In the current study, 115 board meetings were observed using the School Board Video Project (SBVP survey, which was created in 2012 by researchers to uncover school board meetings’ effectiveness. MANOVA, Univariate ANOVA, and Pearson Chi-Square test results revealed significant differences between low-, medium-, and high-performing districts’ school board meetings. Evidence indicated that low-performing districts’ board meetings were: less orderly; had less time spent on student achievement; lacked respectful and attentive engagement across speakers; had board meeting members who seemed to advance their own agenda; had less effective working relationships among the governance team; had fewer board members who relied on the superintendent for advice and input; had one member, other than the board president, stand out for taking excessive time during meetings; and did not focus on policy items as much as high- and medium-performing school districts. The research concluded that more school board members from low-performing districts needed training to improve their effectiveness. Furthermore, highly refined and target-enhanced school board training programs might lead to lasting governance success and more effective teaming that could improve district, and ultimately, student achievement.

  4. Low-frequency oscillations in Hall thrusters

    International Nuclear Information System (INIS)

    Wei Li-Qiu; Han Liang; Yu Da-Ren; Guo Ning

    2015-01-01

    In this paper, we summarize the research development of low-frequency oscillations in the last few decades. The findings of physical mechanism, characteristics and stabilizing methods of low-frequency oscillations are discussed. It shows that it is unreasonable and incomplete to model an ionization region separately to analyze the physical mechanism of low-frequency oscillations. Electro-dynamics as well as the formation conditions of ionization distribution play an important role in characteristics and stabilizing of low-frequency oscillations. Understanding the physical mechanism and characteristics of low- frequency oscillations thoroughly and developing a feasible method stabilizing this instability are still important research subjects. (review)

  5. Low-Power Wireless Sensor Network Infrastructures

    DEFF Research Database (Denmark)

    Hansen, Morten Tranberg

    Advancements in wireless communication and electronics improving form factor and hardware capabilities has expanded the applicability of wireless sensor networks. Despite these advancements, devices are still limited in terms of energy which creates the need for duty-cycling and low-power protocols...... peripherals need to by duty-cycled and the low-power wireless radios are severely influenced by the environmental effects causing bursty and unreliable wireless channels. This dissertation presents a communication stack providing services for low-power communication, secure communication, data collection......, and network management which enables construction of low-power wireless sensor network applications. More specifically, these services are designed with the extreme low-power scenarios of the SensoByg project in mind and are implemented as follows. First, low-power communication is implemented with Auto...

  6. Low-intensity conflict in multinational corporations

    DEFF Research Database (Denmark)

    Lauring, Jakob; Andersen, Poul Houman; Storgaard, Marianne

    2017-01-01

    in four Danish MNCs. Findings: They describe consequences of low-intensity conflict and identify three types of actions by headquarters’ representatives that could lead to the development of low-intensity conflicts, namely, ignoring, bypassing and educating. Originality/value: Very few studies have dealt......Purpose: This paper aims to identify antecedents for, and consequences of, low-intensity inter-unit conflict in multinational corporations (MNCs). Inter-unit conflict in MNCs is an important and well-researched theme. However, while most studies have focused on open conflict acknowledged by both...... parties, much less research has dealt with low-intensity conflicts. Still, low-intensity conflicts can be highly damaging – not least because they are rarely resolved. Design/methodology/approach: The authors used a qualitative approach to understanding low-intensity conflict relying on 170 interviews...

  7. 77 FR 65139 - Designation of Low-Income Status; Acceptance of Secondary Capital Accounts by Low-Income...

    Science.gov (United States)

    2012-10-25

    ...-Income Status; Acceptance of Secondary Capital Accounts by Low-Income Designated Credit Unions AGENCY... amend its low-income credit unions regulation by extending the time credit unions have to accept a low- income designation. Under the current rule, an FCU that has received notification from NCUA that it...

  8. 78 FR 4030 - Designation of Low-Income Status; Acceptance of Secondary Capital Accounts by Low-Income...

    Science.gov (United States)

    2013-01-18

    ...-Income Status; Acceptance of Secondary Capital Accounts by Low-Income Designated Credit Unions AGENCY... amending its low-income credit unions regulation by extending the time period in which a federal credit union (FCU) may accept a low-income designation. Under the current rule, an FCU that receives notice...

  9. Low Risk Anomalies?

    DEFF Research Database (Denmark)

    Schneider, Paul; Wagner, Christian; Zechner, Josef

    . Empirically, we find that option-implied ex-ante skewness is strongly related to ex-post residual coskewness and alphas. Beta- and volatility-based low risk anomalies are largely driven by a single principal component, which is in turn largely explained by skewness. Controlling for skewness renders the alphas......This paper shows that stocks' CAPM alphas are negatively related to CAPM betas if investors demand compensation for negative skewness. Thus, high (low) beta stocks appear to underperform (outperform). This apparent anomaly merely reflects compensation for residual coskewness ignored by the CAPM...... of betting-against-beta and -volatility insignificant....

  10. Inelastic light scattering by low-lying excitations of electrons in low-dimensional semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Pellegrini, V. [NEST CNR-INFM and Scuola Normale Superiore, Pisa (Italy); Pinczuk, A. [Department of Physics, Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States); Bell Laboratories, Lucent Technologies, Murray Hill, New Jersey (United States)

    2006-11-15

    The low-dimensional electron systems that reside in artificial semiconductor heterostructures of great perfection are a contemporary materials base for explorations of collective phenomena. Studies of low-lying elementary excitations by inelastic light scattering offer insights on properties such energetics, interactions and spin magnetization. We review here recent light scattering results obtained from two-dimensional (2D) quantum fluids in semiconductor heterostructures under extreme conditions of low temperature and large magnetic field, where the quantum Hall phases are archetypes of novel behaviors. We also consider recent light scattering experiments that have probed the excitation spectra of few-electron states in semiconductor quantum dots. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  11. Development skills of children born premature with low and very low birth weight.

    Science.gov (United States)

    Ribeiro, Camila da Costa; Pachelli, Mariane Regina de Oliveira; Amaral, Natalie Camillo de Oliveira; Lamônica, Dionísia Aparecida Cusin

    2017-01-30

    To compare the performance of children born premature with low birth weight (LBW) and very low birth-weight (VLBW) with that of children born at term, within the age range of one to three years, regarding child development in the gross motor, fine motor-adaptive, personal-social and language domains. This is a cross-sectional study in a cohort of 150 infants born premature (experimental group) and at term (control group) divided into eight groups with respect to weight (low birth weight: motor, fine motor-adaptive, personal-social and language domains. In this study, the preterm groups presented different performances, i.e., normative, average, and below average performances were observed within the same group.

  12. Low-Dose-Rate Brachytherapy Versus Cryotherapy in Low- and Intermediate-Risk Prostate Cancer

    International Nuclear Information System (INIS)

    Gestaut, Matthew M.; Cai, Wendi; Vyas, Shilpa; Patel, Belur J.; Hasan, Salman A.; MunozMaldonado, Yolanda; Deb, Niloyjyoti; Swanson, Gregory

    2017-01-01

    Purpose: Cryotherapy and brachytherapy are definitive local treatment options for low- to intermediate-risk prostate cancer. There are both prospective and retrospective data for brachytherapy, but the use of cryotherapy has been limited primarily to single-institution retrospective studies. Currently, no published evidence has compared low-dose-rate brachytherapy versus cryotherapy. Methods and Materials: Institutional review board approval was obtained to conduct a retrospective chart review of consecutive patients treated at our institution from 1990 to 2012. For inclusion, patients must have received a prostate cancer diagnosis and have been considered to have low- to intermediate-risk disease according to the National Comprehensive Cancer Network criteria. All patients received brachytherapy or cryotherapy treatment. Disease specifics and failure details were collected for all patients. Failure was defined as prostate-specific antigen nadir +2 ng/mL. Results: A total of 359 patients were analyzed. The groups comprised 50 low-risk cryotherapy (LRC), 92 intermediate-risk cryotherapy (IRC), 133 low-risk brachytherapy (LRB), and 84 intermediate-risk brachytherapy (IRB) patients. The median prostate-specific antigen follow-up periods were 85.6 months (LRC), 59.2 months (IRC), 74.9 months (LRB), and 59.8 months (IRB). The 5-year biochemical progression–free survival (bPFS) rate was 57.9% in the cryotherapy group versus 89.6% in the brachytherapy group (P<.0001). The 5-year bPFS rate was 70.0% (LRC), 51.4% (IRC), 89.4% (LRB), and 89.7% (IRB). The bPFS rate was significantly different between brachytherapy and cryotherapy for low- and intermediate-risk groups (P<.05). The mean nadir temperature reached for cryotherapy patients was −35°C (range, −96°C to −6°C). Cryotherapy used a median of 2 freeze-thaw cycles (range, 2-4 freeze-thaw cycles). Conclusions: Results from this study suggest that cryotherapy is inferior to brachytherapy for patients with

  13. Low-Dose-Rate Brachytherapy Versus Cryotherapy in Low- and Intermediate-Risk Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Gestaut, Matthew M., E-mail: Matthew.Gestaut@BSWHealth.org [Department of Radiation Oncology, Baylor Scott and White Memorial Hospital, Texas A& M University School of Medicine, Temple, Texas (United States); Cai, Wendi [Department of Biostatistics, Baylor Scott and White Health, Temple, Texas (United States); Vyas, Shilpa [Department of Radiation Oncology, Swedish Cancer Institute, Seattle, Washington (United States); Patel, Belur J. [Department of Urology, Baylor Scott and White Memorial Hospital, Texas A& M University School of Medicine, Temple, Texas (United States); Hasan, Salman A. [Department of Radiation Oncology, Baylor Scott and White Memorial Hospital, Texas A& M University School of Medicine, Temple, Texas (United States); MunozMaldonado, Yolanda [Department of Biostatistics, Baylor Scott and White Health, Temple, Texas (United States); Deb, Niloyjyoti; Swanson, Gregory [Department of Radiation Oncology, Baylor Scott and White Memorial Hospital, Texas A& M University School of Medicine, Temple, Texas (United States)

    2017-05-01

    Purpose: Cryotherapy and brachytherapy are definitive local treatment options for low- to intermediate-risk prostate cancer. There are both prospective and retrospective data for brachytherapy, but the use of cryotherapy has been limited primarily to single-institution retrospective studies. Currently, no published evidence has compared low-dose-rate brachytherapy versus cryotherapy. Methods and Materials: Institutional review board approval was obtained to conduct a retrospective chart review of consecutive patients treated at our institution from 1990 to 2012. For inclusion, patients must have received a prostate cancer diagnosis and have been considered to have low- to intermediate-risk disease according to the National Comprehensive Cancer Network criteria. All patients received brachytherapy or cryotherapy treatment. Disease specifics and failure details were collected for all patients. Failure was defined as prostate-specific antigen nadir +2 ng/mL. Results: A total of 359 patients were analyzed. The groups comprised 50 low-risk cryotherapy (LRC), 92 intermediate-risk cryotherapy (IRC), 133 low-risk brachytherapy (LRB), and 84 intermediate-risk brachytherapy (IRB) patients. The median prostate-specific antigen follow-up periods were 85.6 months (LRC), 59.2 months (IRC), 74.9 months (LRB), and 59.8 months (IRB). The 5-year biochemical progression–free survival (bPFS) rate was 57.9% in the cryotherapy group versus 89.6% in the brachytherapy group (P<.0001). The 5-year bPFS rate was 70.0% (LRC), 51.4% (IRC), 89.4% (LRB), and 89.7% (IRB). The bPFS rate was significantly different between brachytherapy and cryotherapy for low- and intermediate-risk groups (P<.05). The mean nadir temperature reached for cryotherapy patients was −35°C (range, −96°C to −6°C). Cryotherapy used a median of 2 freeze-thaw cycles (range, 2-4 freeze-thaw cycles). Conclusions: Results from this study suggest that cryotherapy is inferior to brachytherapy for patients with

  14. Electrical Resistance Alloys and Low-Expansion Alloys

    DEFF Research Database (Denmark)

    Kjer, Torben

    1996-01-01

    The article gives an overview of electrical resistance alloys and alloys with low thermal expansion. The electrical resistance alloys comprise resistance alloys, heating alloys and thermostat alloys. The low expansion alloys comprise alloys with very low expansion coefficients, alloys with very low...... thermoelastic coefficients and age hardenable low expansion alloys....

  15. Effects of a low-fat versus a low-carbohydrate diet on adipocytokines in obese adults.

    Science.gov (United States)

    de Luis, D A; Aller, R; Izaola, O; Gonzalez Sagrado, M; Bellioo, D; Conde, R

    2007-01-01

    There are few studies addressing the effect of weight loss on circulating levels of adipocytokines. The aim of our study was to determine whether different diets would have different weight loss effects and to examine the changes in adipocytokine levels. A population of 90 obesity non-diabetic outpatients was analyzed in a prospective way. The patients were randomly allocated to two groups: (a) diet I (low-fat diet), and (b) diet II (low-carbohydrate diet). At baseline and after 3 months on the diet, adipocytokines were evaluated. 43 patients were randomized to group I and 47 patients to diet group II. No differences were detected between weight loss in either group (3.3 +/- 0.51 vs. 4.4 +/- 0.6 kg; n.s.). In group I, a significant decrease in leptin levels was found. In group II, leptin and C-reactive protein (CRP) levels also decreased. The decrease in leptin levels was lower with diet I than II (16.4 vs. 22.8%; p low-fat and low-carbohydrate diets, without changes in other adipocytokines. The decrease in leptin and CRP levels were higher with a low-carbohydrate diet than a low-fat diet. Copyright 2007 S. Karger AG, Basel.

  16. Low activation diagnostic equipment design studies

    International Nuclear Information System (INIS)

    Hopkins, G.R.; Cheng, E.T.; Fisher, R.K.

    1985-01-01

    The low activation fusion concept has been applied to the diagnostic equipment in a fusion reactor. The components where fabrication from low activation materials is feasible have been identified. Other systems where higher activation elements are required can have their activation reduced by design approaches which include shielding and operation only in low flux regions of the reactor. Some components will not operate in a high flux so activation is not a major concern. This low activation diagnostic equipment study completes a series of low activation studies where all the components in a fusion power reactor have now been evaluated. It is concluded that a completely low activation fusion reactor is feasible with all components meeting the functional requirements. This provides an environmentally benign energy source with a high confidence level in meeting safety criteria in operation, maintenance and waste disposal

  17. Low Vision Rehabilitation and Diabetic Retinopathy

    International Nuclear Information System (INIS)

    Khan, Sarfaraz A.

    2007-01-01

    Diabetic retinopathy is emerging as a major cause of blindness. Diabetic retinopathy calls for a multidisciplinary to the patients. Management of the patient requires a team work by the internist, diabetologist, dietician, ophthalmologist and low vision therapist. Diabetic retinopathy very often results in vision loss. It is important for ophthalmologist to recognize the importance of low vision rehabilitation in formulating appropriate treatment strategies. People with low vision loss due to diabetic retinopathy usually experience difficulty in daily life. Most people with diabetic retinopathy (who have remaining useful vision) can be helped with low vision devices. However, often one low vision device may not be suitable for all purposes. A comprehensive low vision evaluation is required to assess the person's current visual status, identify the goals and the visual needs, and then design an individualized vision rehabilitation program to meet these needs. (author)

  18. Dynamics of low density coronal plasma in low current x-pinches

    International Nuclear Information System (INIS)

    Haas, D; Bott, S C; Vikhrev, V; Eshaq, Y; Ueda, U; Zhang, T; Baranova, E; Krasheninnikov, S I; Beg, F N

    2007-01-01

    Experiments were performed on an x-pinch using a pulsed power current generator capable of producing an 80 kA current with a rise time of 50 ns. Molybdenum wires with and without gold coating were employed to study the effect of high z coating on the low-density ( 18 cm -3 ) coronal plasma dynamics. A comparison of images from XUV frames and optical probing shows that the low density coronal plasma from the wires initially converges at the mid-plane immediately above and below the cross-point. A central jet is formed which moves with a velocity of 6 x 10 4 ms -1 towards both electrodes forming a z-pinch column before the current maximum. A marked change in the low density coronal plasma dynamics was observed when molybdenum wires coated with ∼ 0.09 μm of gold were used. The processes forming the jet structure were delayed relative to bare Mo x-pinches, and the time-resolved x-ray emission also showed differences. An m = 0 instability was observed in the coronal plasma along the x-pinch legs, which were consistent with x-ray PIN diode signals in which x-ray pulses were observed before x-ray spot formation. These early time x-ray pulses were not observed with pure molybdenum x-pinches. These observations indicate that a thin layer of gold coating significantly changes the coronal plasma behaviour. Two dimensional MHD simulations were performed and qualitatively agree with experimental observations of low density coronal plasma

  19. Tracking polar lows in CLM

    Energy Technology Data Exchange (ETDEWEB)

    Zahn, M.; Storch, H. von [Inst. for Coastal Research, GKSS Research Center, Geesthacht (Germany); Meteorological Inst., Univ. of Hamburg (Germany)

    2008-08-15

    Polar lows are severe cyclones in sub-polar oceans sized beyond the resolved scale of existing global reanalysis products. We used the NCEP/NCAR reanalyses data to drive a regional climate model (CLM) in order to reproduce finer resolved atmospheric fields over the North Atlantic over a two year period. In these fields we detected polar lows by means of a detection algorithm based on a spatial digital bandpass filter. CLM was run in two different ways, the conventional way and with additionally prescribing the analysed large scale situation. The resulting temporal and spatial distributions of polar lows between the different simulations are compared. A reasonable seasonal cycle and spatial distribution was found for all simulations. A lower number of polar lows in the spectral nudged simulation indicates a closer vicinity to reality. Higher temporal and spatial variability between the conventional simulations suggest a more random generation of polar lows. Frequency distributions of track-lengths reveal shorter tracks when nudging is applied. Maximum wind speeds reveal only minor, insignificant differences between all runs and are higher in conventional mode. (orig.)

  20. Berkeley Low Background Facility

    International Nuclear Information System (INIS)

    Thomas, K. J.; Norman, E. B.; Smith, A. R.; Poon, A. W. P.; Chan, Y. D.; Lesko, K. T.

    2015-01-01

    The Berkeley Low Background Facility (BLBF) at Lawrence Berkeley National Laboratory (LBNL) in Berkeley, California provides low background gamma spectroscopy services to a wide array of experiments and projects. The analysis of samples takes place within two unique facilities; locally within a carefully-constructed, low background laboratory on the surface at LBNL and at the Sanford Underground Research Facility (SURF) in Lead, SD. These facilities provide a variety of gamma spectroscopy services to low background experiments primarily in the form of passive material screening for primordial radioisotopes (U, Th, K) or common cosmogenic/anthropogenic products; active screening via neutron activation analysis for U,Th, and K as well as a variety of stable isotopes; and neutron flux/beam characterization measurements through the use of monitors. A general overview of the facilities, services, and sensitivities will be presented. Recent activities and upgrades will also be described including an overview of the recently installed counting system at SURF (recently relocated from Oroville, CA in 2014), the installation of a second underground counting station at SURF in 2015, and future plans. The BLBF is open to any users for counting services or collaboration on a wide variety of experiments and projects

  1. Occupant satisfaction with new low-energy houses

    DEFF Research Database (Denmark)

    Knudsen, Henrik Nellemose; Jensen, Ole Michael; Kristensen, Lars

    2012-01-01

    The development and the erection of low-energy buildings have been intensified in recent years. Still, there are only few studies of the energy performance and occupant satisfaction with living in low-energy houses. A questionnaire survey was therefore carried out among occupants of low-energy ho......The development and the erection of low-energy buildings have been intensified in recent years. Still, there are only few studies of the energy performance and occupant satisfaction with living in low-energy houses. A questionnaire survey was therefore carried out among occupants of low......-energy houses. The purpose was to study occupant satisfaction with new low-energy houses concerning i.a. the perceived indoor climate and the technical installations for heating and ventilation. The survey showed an overall satisfaction with the new low-energy houses, but also that there were problems...... occupant satisfaction in existing and future low-energy houses are given....

  2. Cancer risk of low dose/low dose rate radiation: a meta-analysis of cancer data of mammals exposed to low doses of radiation

    International Nuclear Information System (INIS)

    Ogata, Hiromitsu; Magae, Junji

    2008-01-01

    Full text: Linear No Threshold (LNT) model is a basic theory for radioprotection, but the adaptability of this hypothesis to biological responses at low doses or at low dose rates is not sufficiently investigated. Simultaneous consideration of the cumulative dose and the dose rate is necessary for evaluating the risk of long-term exposure to ionizing radiation at low dose. This study intends to examine several numerical relationships between doses and dose rates in biological responses to gamma radiation. Collected datasets on the relationship between dose and the incidence of cancer in mammals exposed to low doses of radiation were analysed using meta-regression models and modified exponential (MOE) model, which we previously published, that predicts irradiation time-dependent biological response at low dose rate ionizing radiation. Minimum doses of observable risk and effective doses with a variety of dose rates were calculated using parameters estimated by fitting meta-regression models to the data and compared them with other statistical models that find values corresponding to 'threshold limits'. By fitting a weighted regression model (fixed-effects meta-regression model) to the data on risk of all cancers, it was found that the log relative risk [log(RR)] increased as the total exposure dose increased. The intersection of this regression line with the x-axis denotes the minimum dose of observable risk. These estimated minimum doses and effective doses increased with decrease of dose rate. The goodness of fits of MOE-model depended on cancer types, but the total cancer risk is reduced when dose rates are very low. The results suggest that dose response curve for cancer risk is remarkably affected by dose rate and that dose rate effect changes as a function of dose rate. For scientific discussion on the low dose exposure risk and its uncertainty, the term 'threshold' should be statistically defined, and dose rate effects should be included in the risk

  3. Explaining Asset Prices with Low Risk Aversion and Low Intertemporal Substitution

    DEFF Research Database (Denmark)

    Andreasen, Martin Møller; Jørgensen, Kasper

    model to explain asset prices with a low relative risk aversion (RRA) of 9.8 and a low intertemporal elasticity of substitution (IES) of 0:11. We also show that the proposed preferences allow an otherwise standard New Keynesian model to match the equity premium, the bond premium, and the risk-free rate......This paper extends the class of Epstein-Zin-Weil preferences with a new utility kernel that disentangles uncertainty about the consumption trend (long-run risk) from short-term variation around this trend (cyclical risk). Our estimation results show that these preferences enable the long-run risk...

  4. Low activation ferritic alloys

    Science.gov (United States)

    Gelles, David S.; Ghoniem, Nasr M.; Powell, Roger W.

    1986-01-01

    Low activation ferritic alloys, specifically bainitic and martensitic stainless steels, are described for use in the production of structural components for nuclear fusion reactors. They are designed specifically to achieve low activation characteristics suitable for efficient waste disposal. The alloys essentially exclude molybdenum, nickel, nitrogen and niobium. Strength is achieved by substituting vanadium, tungsten, and/or tantalum in place of the usual molybdenum content in such alloys.

  5. Low-flow characteristics of Virginia streams

    Science.gov (United States)

    Austin, Samuel H.; Krstolic, Jennifer L.; Wiegand, Ute

    2011-01-01

    Low-flow annual non-exceedance probabilities (ANEP), called probability-percent chance (P-percent chance) flow estimates, regional regression equations, and transfer methods are provided describing the low-flow characteristics of Virginia streams. Statistical methods are used to evaluate streamflow data. Analysis of Virginia streamflow data collected from 1895 through 2007 is summarized. Methods are provided for estimating low-flow characteristics of gaged and ungaged streams. The 1-, 4-, 7-, and 30-day average streamgaging station low-flow characteristics for 290 long-term, continuous-record, streamgaging stations are determined, adjusted for instances of zero flow using a conditional probability adjustment method, and presented for non-exceedance probabilities of 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.05, 0.02, 0.01, and 0.005. Stream basin characteristics computed using spatial data and a geographic information system are used as explanatory variables in regional regression equations to estimate annual non-exceedance probabilities at gaged and ungaged sites and are summarized for 290 long-term, continuous-record streamgaging stations, 136 short-term, continuous-record streamgaging stations, and 613 partial-record streamgaging stations. Regional regression equations for six physiographic regions use basin characteristics to estimate 1-, 4-, 7-, and 30-day average low-flow annual non-exceedance probabilities at gaged and ungaged sites. Weighted low-flow values that combine computed streamgaging station low-flow characteristics and annual non-exceedance probabilities from regional regression equations provide improved low-flow estimates. Regression equations developed using the Maintenance of Variance with Extension (MOVE.1) method describe the line of organic correlation (LOC) with an appropriate index site for low-flow characteristics at 136 short-term, continuous-record streamgaging stations and 613 partial-record streamgaging stations. Monthly

  6. Transportation and disposal configuration for DOE-managed low-level and mixed low-level waste

    International Nuclear Information System (INIS)

    Johnsen, T.

    1993-06-01

    This report briefly examines the current U.S. Department of Energy complex-wide configuration for transportation and disposal of low-level and mixed low-level waste, and also retraces the historical sequence of events and rationale that has guided its development. The study determined that Nevada Test Site and the Hanford Site are the only two sites that currently provide substantial disposal services for offsite low-level waste generators. It was also determined that mixed low-level waste shipments are infrequent and are generally limited to shipments to offsite commercial treatment facilities or other Department of Energy sites for storage. The current alignment of generator to disposal site for low-level waste shipments is generally consistent with the programmatic mission of the generator; that is, defense-generated waste is shipped to the Nevada Test Site and research-generated waste is transported to the Hanford Site. The historical development of the current configuration was resurrected by retrieving Department of Energy documentation and interviewing both current and former department and contractor personnel. According to several accounts, the basic framework of the system was developed during the late 1970s, and was reportedly based on the ability of the disposal site to manage a given waste form. Documented evidence to support this reasoning, however, could not be uncovered

  7. Low to moderate temperature nanolaminate heater

    Science.gov (United States)

    Eckels, J Del [Livermore, CA; Nunes, Peter J [Danville, CA; Simpson, Randall L [Livermore, CA; Hau-Riege, Stefan [Fremont, CA; Walton, Chris [Oakland, CA; Carter, J Chance [Livermore, CA; Reynolds, John G [San Ramon, CA

    2011-01-11

    A low to moderate temperature heat source comprising a high temperature energy source modified to output low to moderate temperatures wherein the high temperature energy source modified to output low to moderate temperatures is positioned between two thin pieces to form a close contact sheath. In one embodiment the high temperature energy source modified to output low to moderate temperatures is a nanolaminate multilayer foil of reactive materials that produces a heating level of less than 200.degree. C.

  8. Claudin-Low Breast Cancer; Clinical & Pathological Characteristics.

    Directory of Open Access Journals (Sweden)

    Kay Dias

    Full Text Available Claudin-low breast cancer is a molecular type of breast cancer originally identified by gene expression profiling and reportedly associated with poor survival. Claudin-low tumors have been recognised to preferentially display a triple-negative phenotype, however only a minority of triple-negative breast cancers are claudin-low. We sought to identify an immunohistochemical profile for claudin-low tumors that could facilitate their identification in formalin fixed paraffin embedded tumor material. First, an in silico collection of ~1600 human breast cancer expression profiles was assembled and all claudin-low tumors identified. Second, genes differentially expressed between claudin-low tumors and all other molecular subtypes of breast cancer were identified. Third, a number of these top differentially expressed genes were tested using immunohistochemistry for expression in a diverse panel of breast cancer cell lines to determine their specificity for claudin-low tumors. Finally, the immunohistochemical panel found to be most characteristic of claudin-low tumors was examined in a cohort of 942 formalin fixed paraffin embedded human breast cancers with >10 years clinical follow-up to evaluate the clinico-pathologic and survival characteristics of this tumor subtype. Using this approach we determined that claudin-low breast cancer is typically negative for ER, PR, HER2, claudin 3, claudin 4, claudin 7 and E-cadherin. Claudin-low tumors identified with this immunohistochemical panel, were associated with young age of onset, higher tumor grade, larger tumor size, extensive lymphocytic infiltrate and a circumscribed tumor margin. Patients with claudin-low tumors had a worse overall survival when compared to patients with luminal A type breast cancer. Interestingly, claudin-low tumors were associated with a low local recurrence rate following breast conserving therapy. In conclusion, a limited panel of antibodies can facilitate the identification of

  9. Resources for Adapting Low Vision Training Materials for the Adult with Low Literacy Skills. Practice Report

    Science.gov (United States)

    Tucker, Laurel A.

    2004-01-01

    Adults with low vision who seek clinical low vision services need to be able to read (that is, to interpret or understand words, numbers, and symbols in print meaningfully). Reading difficulties that adults encounter during low vision therapy may be directly connected to a visual impairment or may be related to other reading problems, such as…

  10. Are low back pain and low physical capacity risk indicators for dropout among recently qualified eldercare workers?

    DEFF Research Database (Denmark)

    Faber, Anne; Giver, Hanne; Strøyer, Jesper

    2010-01-01

    BACKGROUND: A high job turnover and dropout among eldercare workers has led to a significant shortage of qualified manpower in the Danish eldercare sector. OBJECTIVES: The predictive effect of some non-work-related causes for leaving the eldercare sector 2 years after qualification, physical...... either in the eldercare sector, in other health- and welfare sectors, in all other sectors, under education, or outside labour market, 2 years after qualification. RESULTS: Disability due to and duration of low back pain were significant predictors for dropout from the eldercare sector 2 years after...... qualification. Low physical capacity was not. Data on duration of low back pain suggest a trend towards a dose-response relationship: The longer the duration of low back pain, the higher odds for dropout. CONCLUSIONS: Low back pain and disability due to low back pain during the last year of education were...

  11. Controlling low-level radioactive waste

    International Nuclear Information System (INIS)

    1990-01-01

    This series of information sheets describes at a popular level the sources of low-level radioactive wastes, their associated hazards, methods of storage, transportation and disposal, and the Canadian regulations that cover low-level wastes

  12. Diel use of a saltwater creek by white-tip reef sharks Triaenodon obesus (Carcharhiniformes: Carcharhinidae in Academy Bay, Galapagos Islands

    Directory of Open Access Journals (Sweden)

    César Peñaherrera

    2012-06-01

    Full Text Available White-tip reef sharks are common inhabitants of the shallow waters surrounding the Galapagos Islands, where several known aggregation sites have become touristic attractions. With the aim to describe site fidelity and residency patterns of the white-tip reef sharks in a saltwater creek, we used the ultrasonic telemetry method. The study was undertaken in a saltwater channel South of Academy Bay, Santa Cruz Island, from May 2008-September 2009. A total of nine transmitters were attached to sharks and ultrasonic receivers were deployed at the inner and outside areas of the creek. From the total of fitted sharks, four lost their transmitters. The results obtained with the remaining sharks showed an elevated use of the inner area of the channel during the day, with more use of the external area during the night. However, none of the sharks were detected at the site every day, suggesting that they may have a number of preferred sites within their home range. More studies are needed to detail the home range and habitat use of this species, and to guide its protection level in the AcademyBay area. Rev. Biol. Trop. 60 (2: 735-743. Epub 2012 June 01.Los tiburones punta blanca de arrecife son habitantes comunes de las aguas que rodean las Islas Galápagos, por lo que muchos de sus sitios de agregación se han convertido en atractivos turísticos. Con el objetivo de describir la fidelidad del sitio y los patrones de residencia de nueve tiburones desde mayo 2008-septiembre 2009, se utilizó telemetría ultrasónica en un canal de agua salada en el sur de Bahía Academia, Isla Santa Cruz. A pesar de que cuatro tiburones perdieron sus transmisores, los restantes tiburones monitoreados mostraron un uso elevado del interior del canal durante el día y del exterior durante la noche. Sin embargo, ninguno de los tiburones fue detectado en el sitio diariamente, lo cual sugiere que deben tener un número mayor de sitios preferidos dentro de su área de vida.

  13. Diel use of a saltwater creek by white-tip reef sharks Triaenodon obesus (Carcharhiniformes: Carcharhinidae in Academy Bay, Galapagos Islands

    Directory of Open Access Journals (Sweden)

    César Peñaherrera

    2012-06-01

    Full Text Available White-tip reef sharks are common inhabitants of the shallow waters surrounding the Galapagos Islands, where several known aggregation sites have become touristic attractions. With the aim to describe site fidelity and residency patterns of the white-tip reef sharks in a saltwater creek, we used the ultrasonic telemetry method. The study was undertaken in a saltwater channel South of Academy Bay, Santa Cruz Island, from May 2008-September 2009. A total of nine transmitters were attached to sharks and ultrasonic receivers were deployed at the inner and outside areas of the creek. From the total of fitted sharks, four lost their transmitters. The results obtained with the remaining sharks showed an elevated use of the inner area of the channel during the day, with more use of the external area during the night. However, none of the sharks were detected at the site every day, suggesting that they may have a number of preferred sites within their home range. More studies are needed to detail the home range and habitat use of this species, and to guide its protection level in the AcademyBay area. Rev. Biol. Trop. 60 (2: 735-743. Epub 2012 June 01.

  14. Diel use of a saltwater creek by white-tip reef sharks Triaenodon obesus (Carcharhiniformes: Carcharhinidae) in Academy Bay, Galapagos Islands.

    Science.gov (United States)

    Peñiaherrera, César; Hearn, Alex R; Kuhn, Angela

    2012-06-01

    White-tip reef sharks are common inhabitants of the shallow waters surrounding the Galapagos Islands, where several known aggregation sites have become touristic attractions. With the aim to describe site fidelity and residency patterns of the white-tip reef sharks in a saltwater creek, we used the ultrasonic telemetry method. The study was undertaken in a saltwater channel South of Academy Bay, Santa Cruz Island, from May 2008-September 2009. A total of nine transmitters were attached to sharks and ultrasonic receivers were deployed at the inner and outside areas of the creek. From the total of fitted sharks, four lost their transmitters. The results obtained with the remaining sharks showed an elevated use of the inner area of the channel during the day, with more use of the external area during the night. However, none of the sharks were detected at the site every day, suggesting that they may have a number of preferred sites within their home range. More studies are needed to detail the home range and habitat use of this species, and to guide its protection level in the Academy Bay area.

  15. A low-cost, ultra-fast and ultra-low noise preamplifier for silicon avalanche photodiodes

    Science.gov (United States)

    Gasmi, Khaled

    2018-02-01

    An ultra-fast and ultra-low noise preamplifier for amplifying the fast and weak electrical signals generated by silicon avalanche photodiodes has been designed and developed. It is characterized by its simplicity, compactness, reliability and low cost of construction. A very wide bandwidth of 300 MHz, a very good linearity from 1 kHz to 280 MHz, an ultra-low noise level at the input of only 1.7 nV Hz-1/2 and a very good stability are its key features. The compact size (70 mm  ×  90 mm) and light weight (45 g), as well as its excellent characteristics, make this preamplifier very competitive compared to any commercial preamplifier. The preamplifier, which is a main part of the detection system of a homemade laser remote sensing system, has been successfully tested. In addition, it is versatile and can be used in any optical detection system requiring high speed and very low noise electronics.

  16. Low-energy office buildings using existing technology. Simulations with low internal heat gains

    Energy Technology Data Exchange (ETDEWEB)

    Flodberg, Kajsa; Blomsterberg, Aake; Dubois, Marie-Claude [Lund Univ. (Sweden). Div. of Energy and Building Design

    2012-11-01

    Although low-energy and nearly zero-energy residential houses have been built in Sweden in the past decade, there are very few examples of low-energy office buildings. This paper investigates the design features affecting energy use in office buildings and suggests the optimal low-energy design from a Swedish perspective. Dynamic simulations have been carried out with IDA ICE 4 on a typical narrow office building with perimeter cell rooms. The results from the parametric study reveal that the most important design features for energy saving are demand-controlled ventilation as well as limited glazing on the facade. Further energy-saving features are efficient lighting and office equipment which strongly reduce user-related electricity and cooling energy. Together, the simulation results suggest that about 48% energy can be saved compared to a new office building built according to the Swedish building code. Thus, it is possible, using a combination of simple and well-known building technologies and configurations, to have very low energy use in new office buildings. If renewable energy sources, such as solar energy and wind power, are added, there is a potential for the annual energy production to exceed the annual energy consumption and a net zero-energy building can be reached. One aspect of the results concerns user-related electricity, which becomes a major energy post in very low-energy offices and which is rarely regulated in building codes today. This results not only in high electricity use, but also in large internal heat gains and unnecessary high cooling loads given the high latitude and cold climate. (orig.)

  17. A Low-Pressure Oxygen Storage System for Oxygen Supply in Low-Resource Settings.

    Science.gov (United States)

    Rassool, Roger P; Sobott, Bryn A; Peake, David J; Mutetire, Bagayana S; Moschovis, Peter P; Black, Jim Fp

    2017-12-01

    Widespread access to medical oxygen would reduce global pneumonia mortality. Oxygen concentrators are one proposed solution, but they have limitations, in particular vulnerability to electricity fluctuations and failure during blackouts. The low-pressure oxygen storage system addresses these limitations in low-resource settings. This study reports testing of the system in Melbourne, Australia, and nonclinical field testing in Mbarara, Uganda. The system included a power-conditioning unit, a standard oxygen concentrator, and an oxygen store. In Melbourne, pressure and flows were monitored during cycles of filling/emptying, with forced voltage fluctuations. The bladders were tested by increasing pressure until they ruptured. In Mbarara, the system was tested by accelerated cycles of filling/emptying and then run on grid power for 30 d. The low-pressure oxygen storage system performed well, including sustaining a pressure approximately twice the standard working pressure before rupture of the outer bag. Flow of 1.2 L/min was continuously maintained to a simulated patient during 30 d on grid power, despite power failures totaling 2.9% of the total time, with durations of 1-176 min (mean 36.2, median 18.5). The low-pressure oxygen storage system was robust and durable, with accelerated testing equivalent to at least 2 y of operation revealing no visible signs of imminent failure. Despite power cuts, the system continuously provided oxygen, equivalent to the treatment of one child, for 30 d under typical power conditions for sub-Saharan Africa. The low-pressure oxygen storage system is ready for clinical field trials. Copyright © 2017 by Daedalus Enterprises.

  18. Value of low-dose 2 X 2 Gy palliative radiotherapy in advanced low-grade non-Hodgkin's lymphoma

    International Nuclear Information System (INIS)

    Ng, M.; Wirth, A.; Ryan, G.; MacManus, M.

    2006-01-01

    Low-dose radiotherapy over the last decade has been reported to provide effective palliation for patients with low-grade non-Hodgkin's lymphoma. In this retrospective case series of 10 patients, we report our early experience using low-dose radiotherapy (usually 2 x2 Gy) for patients with advanced-stage follicular, mucosal associated lymphoid tissue, mantle cell and small lymphocytic lymphomas. Median follow up was 27 weeks. Response rates were high (complete response, 70%; partial response, 20%), the response durable and the toxicity was minimal (no toxicity greater than grade 1). Low-dose irradiation is an effective treatment option for patients with low-grade lymphomas with local symptoms Copyright (2006) Blackwell Publishing Asia Pty Ltd

  19. Low-level waste program technical strategy

    International Nuclear Information System (INIS)

    Bledsoe, K.W.

    1994-01-01

    The Low-Level Waste Technical Strategy document describes the mechanisms which the Low-Level Waste Program Office plans to implement to achieve its mission. The mission is to manage the receipt, immobilization, packaging, storage/disposal and RCRA closure (of the site) of the low-level Hanford waste (pretreated tank wastes) in an environmentally sound, safe and cost-effective manner. The primary objective of the TWRS Low-level waste Program office is to vitrify the LLW fraction of the tank waste and dispose of it onsite

  20. Mitochondrial DNA analysis reveals three stocks of yellowfin tuna Thunnus albacares (Bonnaterre, 1788) in Indian waters

    Digital Repository Service at National Institute of Oceanography (India)

    Kunal, S.P.; GirishKumar; Menezes, M.R.; Meena, R.M.

    was sequenced and analysed for 321 yellowfin samples. Hierarchical analysis of molecular variance showed significant genetic differentiation among three groups (VE); (AG); (KO, TU, PO, VI, PB) analyzed (Theta sub(ST)=0.03844, P less than or equal to 0...

  1. Gamma Irradiation Effects On Thiamin And Riboflavin On Fresh Tuna (Thunnus thynnus) And Salmon (Onchorhynchus gorbuscha)

    International Nuclear Information System (INIS)

    Tanhindarto, Rindy P.; Fox, J.B.; Lakritz, L.; Thayer, D.W.

    2002-01-01

    An experiment have been conducted on the effect of gamma irradiation on thiamine and riboflavin in fresh tuna and salmon. Samples were irradiated at (20 ± 0,5) oC by gamma rays with doses of 0; 2,5 and 5 kGy. The purpose of the present experiment was to study on changes of thiamine and riboflavin contents on extraction of fresh tuna and salmon after and before irradiation. The results showed that irradiation up to 2,5 kGy changed the thiamine and riboflavin contents on fresh tuna as well as their destruction which was significantly increasing caused by irradiated treatment with the dose of 5 kGy. The fresh salmon did not significantly change of the thiamine and riboflavin contents treated by irradiation up to 5 kGy

  2. Chemical composition of protein concentrate prepared from Yellowfin tuna Thunnus albacares roe by cook-dried process

    Directory of Open Access Journals (Sweden)

    Hyun Ji Lee

    2016-05-01

    Full Text Available Abstract Roe is the term used to describe fish eggs (oocytes gathered in skeins and is one of the most valuable food products from fishery sources. Thus, means of processing are required to convert the underutilized yellowfin tuna roes (YTR into more marketable and acceptable forms as protein concentrate. Roe protein concentrates (RPCs were prepared by cooking condition (boil-dried concentrate, BDC and steam-dried concentrate, SDC, respectively and un-cooking condition (freeze-dried concentrate, FDC from yellowfin tuna roe. The yield of RPCs was in the range from 22.2 to 25.3 g/100 g of roe. RPCs contained protein (72.3–77.3 %, moisture (4.3–5.6 %, lipid (10.6–11.3 % and ash (4.3–5.7 % as the major constituents. The prominent amino acids of RPCs were aspartic acid, 8.7–9.2, glutamic acid, 13.1–13.2, and leucine, 8.5–8.6 g/100 g of protein. Major differences were not observed in each of the amino acid. K, S, Na, and P as minerals were the major elements in RPCs. No difference noted in sodium dodecyl sulfate polyacrylamide gel electrophoresis protein band (15–100 K possibly representing partial hydrolysis of myosin. Therefore, RPCs from YTR could be use potential protein ingredient for human food and animal feeds.

  3. Low power constant fraction discriminator

    International Nuclear Information System (INIS)

    Krishnan, Shanti; Raut, S.M.; Mukhopadhyay, P.K.

    2001-01-01

    This paper describes the design of a low power ultrafast constant fraction discriminator, which significantly reduces the power consumption. A conventional fast discriminator consumes about 1250 MW of power whereas this low power version consumes about 440 MW. In a multi detector system, where the number of discriminators is very large, reduction of power is of utmost importance. This low power discriminator is being designed for GRACE (Gamma Ray Atmospheric Cerenkov Experiments) telescope where 1000 channels of discriminators are required. A novel method of decreasing power consumption has been described. (author)

  4. Management of Lowe syndrome: a case report

    Directory of Open Access Journals (Sweden)

    Risky Vitria Prasetyo

    2015-06-01

    Full Text Available Lowe syndrome (the oculocerebrorenal syndrome of Lowe, OCRL is a multisystem disorder characterized by anomalies affecting the eyes, nervous system and kidneys.1-3 The disorder was first recognized by Lowe et al. in 1952, and described as a unique syndrome with organic aciduria, decreased renal ammonia production, hydrophthalmos, and mental retardation. In 1954, renal Fanconi syndrome was recognized as being associated with Lowe syndrome and in 1965, a recessive X-linked pattern of inheritance was determined.2,4 Lowe syndrome is a very rare disease, with an estimated prevalence in the general population of 1 in 500,000. According to the Lowe Syndrome Association (LSA in the USA, the estimated prevalence is between 1 and 10 affected males in 1,000,000 people, with 190 living in the year 2000. The Italian Association of Lowe Syndrome estimated that there were 34 Lowe syndrome patients (33 boys and one girl living in Italy in the year 2005.2,4,5 It almost exclusively affects males.6 Physicians may not be familiar with Lowe syndrome due to its rarity.4

  5. Guideposts for Low Carbon Finance

    International Nuclear Information System (INIS)

    Pizer, Billy

    2015-01-01

    The author proposes four guideposts for efficient low carbon finance: remove subsidies for high-carbon technologies, improve the cost-effectiveness of low-carbon subsidies, encourage private sector innovation and maintain transparent public policy tools that support cost-benefit accounting

  6. Evaluation of physicochemical, textural and sensorial characteristics of low-fat or low-sugar synbiotic ice-cream

    Directory of Open Access Journals (Sweden)

    M Hashemi

    2015-08-01

    Full Text Available Replacing a part of fat and sugar in ice-cream by inulin and lactulose as prebiotic may create a healthier product. Two low-fat and two low-sugar synbiotic ice-cream samples were manufactured inoculated with Lactobacillus acidophilus or Bacillus coagulans. The physicochemical, textural and sensorial characteristics of the samples were compared with regular ice-cream as control. Low-fat and low-sugar synbiotic ice-cream formulations were prepared by replacing 5% of the fat and sugar contents of the control formula by inulin and lactulose, respectively. According to the results, although the total solids of the ice-cream mixes did not differ significantly, there were significant (p

  7. Review of mixer design for low voltage - low power applications

    Science.gov (United States)

    Nurulain, D.; Musa, F. A. S.; Isa, M. Mohamad; Ahmad, N.; Kasjoo, S. R.

    2017-09-01

    A mixer is used in almost all radio frequency (RF) or microwave systems for frequency translation. Nowadays, the increase market demand encouraged the industry to deliver circuit designs to create proficient and convenient equipment with very low power (LP) consumption and low voltage (LV) supply in both digital and analogue circuits. This paper focused on different Complementary Metal Oxide Semiconductor (CMOS) design topologies for LV and LP mixer design. Floating Gate Metal Oxide Semiconductor (FGMOS) is an alternative technology to replace CMOS due to their high ability for LV and LP applications. FGMOS only required a few transistors per gate and can have a shift in threshold voltage (VTH) to increase the LP and LV performances as compared to CMOS, which makes an attractive option to replace CMOS.

  8. Reducing scram frequency by modifying/eliminating steam generator low-low level reactor trip setpoint for Maanshan nuclear power plant

    International Nuclear Information System (INIS)

    Yuann, R.Y.; Chiang, S.C.; Hsiue, J.K.; Chen, P.C.

    1987-01-01

    The feasibility of modification/elimination of steam generator low-low level reactor trip setpoint is evaluated by using RETRAN-02 code for the purpose of reducing scram frequency in Maanshan 3-loop pressurized water reactor. The ANS Condition II event loss of normal feedwater and condition IV event feedwater system line break are the basis for steam generator low-low level reactor trip setpoint sensitivity analysis, including various initial reactor power levels, reactivity feedback coefficients, and system functions assumptions etc., have been performed for the two basis events with steam generator low-low level reactor trip setpoint at 0% narrow range and without this trip respectively. The feasibility of modifying/eliminating current steam generator low-low level reactor trip setpoint is then determined based on whether the analysis results meet with the ANS Condition II and IV acceptance criteria or not

  9. Effect of low-temperature thermomechanical treatment on mechanical properties of low-alloying molybdenum alloys with carbide hardening

    International Nuclear Information System (INIS)

    Bernshtejn, L.M.; Zakharov, A.M.; Veller, M.V.

    1978-01-01

    Presented are results of testing low-temperature thermomechanical treatment of low-alloying molybdenum alloys, including quenching from 2100 deg C, 40% deformation by hydroextrusion and aging at the temperature of 1200-1400 deg C. Tensile tests at room temperature with the following processing of results have shown that low-temperature thermomechanical treatment of low-alloying molybdenum alloys of Mo-Zr-C and Mo-Zr-Nb-C systems leads to a significant increase in low-temperature mechanical properties (strength properties - by 30-35%, ductility - by 30-40%) as compared with conventional heat treatment (aging after quenching). The treatment proposed increases resistance to small, as well as large plastic deformations, and leads to a simultaneous rise of strength and plastic properties at all stages of tensile test. Alloying of the Mo-Zr-C system with niobium increases both strength and plastic characteristics as compared with alloys without niobium when testing samples, subjected to low temperature thermomechanical treatment and conventional heat treatment at room temperature

  10. Low-water considerations for NPP sites

    International Nuclear Information System (INIS)

    Jensen, J.; Frank, T.; Wahl, T.

    2009-01-01

    In the frame of reactor safety considerations flood protection and the evaluation of low-water events are safety relevant issues. Therefore low-water statistics were performed for the coastal region Cuxhaven and the Elbe river estuary. The consideration of the longitudinal profile of water levels during low-tide in connection with surface water effects, morphodynamic changes of the river and anthropogenic modifications is of importance for conclusions concerning the NPP sites in some distance of the reference tide gauge. The authors performed a statistical low-tide analysis for the NPP sites Brunsbuettel and Brokdorf.

  11. Low pH Cements

    International Nuclear Information System (INIS)

    Savage, David; Benbow, Steven

    2007-05-01

    The development of low-pH cements for use in geological repositories for radioactive waste stems from concerns over the potential for deleterious effects upon the host rock and other EBS materials (notably bentonite) under the hyperalkaline conditions (pH > 12) of cement pore fluids. Low pH cement (also known as low heat cement) was developed by the cement industry for use where large masses of cement (e.g. dams) could cause problems regarding heat generated during curing. In low pH cements, the amount of cement is reduced by substitution of materials such as fly ash, blast furnace slag, silica fume, and/or non-pozzolanic silica flour. SKB and Posiva have ruled out the use of blast furnace slag and fly-ash and are focusing on silica fume as a blending agent. Currently, no preferred composition has been identified by these agencies. SKB and Posiva have defined a pH limit ≤ 11 for cement grout leachates. To attain this pH, blending agents must comprise at least 50 wt % of dry materials. Because low pH cement has little, or no free portlandite, the cement consists predominantly of calcium silicate hydrate (CSH) gel with a Ca/Si ratio ≤ 0.8. Although there are potential implications for the performance of the spent fuel and cladding due to the presence of hyperalkaline fluids from cement, the principal focus for safety assessment lies with the behaviour of bentonite. There are a number of potential constraints on the interaction of hyperalkaline cement pore fluids with bentonite, including mass balance, thermodynamic issues, mass transport, and kinetics, but none of these is likely to be limiting if conventional OPC cements are employed in repository construction. Nevertheless: Low-pH cements may supply approximately 50 % less hydroxyl ions than conventional OPC for a given volume of cement, but mass balance constraints are complicated by the uncertainty concerning the type of secondary minerals produced during cement-bentonite interaction. The change of aqueous

  12. Low pH Cements

    Energy Technology Data Exchange (ETDEWEB)

    Savage, David; Benbow, Steven [Quintessa Ltd., Henley-on-Thames (United Kingdom)

    2007-05-15

    The development of low-pH cements for use in geological repositories for radioactive waste stems from concerns over the potential for deleterious effects upon the host rock and other EBS materials (notably bentonite) under the hyperalkaline conditions (pH > 12) of cement pore fluids. Low pH cement (also known as low heat cement) was developed by the cement industry for use where large masses of cement (e.g. dams) could cause problems regarding heat generated during curing. In low pH cements, the amount of cement is reduced by substitution of materials such as fly ash, blast furnace slag, silica fume, and/or non-pozzolanic silica flour. SKB and Posiva have ruled out the use of blast furnace slag and fly-ash and are focusing on silica fume as a blending agent. Currently, no preferred composition has been identified by these agencies. SKB and Posiva have defined a pH limit {<=} 11 for cement grout leachates. To attain this pH, blending agents must comprise at least 50 wt % of dry materials. Because low pH cement has little, or no free portlandite, the cement consists predominantly of calcium silicate hydrate (CSH) gel with a Ca/Si ratio {<=} 0.8. Although there are potential implications for the performance of the spent fuel and cladding due to the presence of hyperalkaline fluids from cement, the principal focus for safety assessment lies with the behaviour of bentonite. There are a number of potential constraints on the interaction of hyperalkaline cement pore fluids with bentonite, including mass balance, thermodynamic issues, mass transport, and kinetics, but none of these is likely to be limiting if conventional OPC cements are employed in repository construction. Nevertheless: Low-pH cements may supply approximately 50 % less hydroxyl ions than conventional OPC for a given volume of cement, but mass balance constraints are complicated by the uncertainty concerning the type of secondary minerals produced during cement-bentonite interaction. The change of aqueous

  13. Directions in low-level radioactive waste management: A brief history of commercial low-level radioactive waste disposal

    International Nuclear Information System (INIS)

    1990-10-01

    This report presents a history of commercial low-level radioactive waste management in the United States, with emphasis on the history of six commercially operated low-level radioactive waste disposal facilities. The report includes a brief description of important steps that have been taken during the 1980s to ensure the safe disposal of low-level waste in the 1990s and beyond. These steps include the issuance of Title 10 Code of Federal Regulations Part 61, Licensing Requirements for the Land Disposal of Radioactive Waste, the Low-Level Radioactive Waste Policy Act of 1980, the Low-Level Radioactive Waste Policy Amendments Act of 1985, and steps taken by states and regional compacts to establish additional disposal sites. 42 refs., 13 figs., 1 tab

  14. Input Stage for Low-Voltage, Low-Noise Preamplifiers Based on a Floating-Gate MOS Transistor

    DEFF Research Database (Denmark)

    Igor, Mucha

    1997-01-01

    A novel input stage for low-voltage, low-noise preamplifiers for integrated capacitive sensors is presented. The input stage of the preamplifier employs floating-gate MOS transistors which are capable of storing the operation point of the input stage over several years without any severe degradat......A novel input stage for low-voltage, low-noise preamplifiers for integrated capacitive sensors is presented. The input stage of the preamplifier employs floating-gate MOS transistors which are capable of storing the operation point of the input stage over several years without any severe...... degradation of the performance of the circuit and without the need for a repeating programming. In this way the noise originating from any resistance previously used for the definition of the operating point is avoided completely and, moreover, by avoiding the input high-pass filter both the saturation...

  15. Low Cost, High-Throughput 3-D Pulmonary Imager Using Hyperpolarized Contrast Agents and Low-Field MRI

    Science.gov (United States)

    2017-10-01

    greater gas polarizations and production amounts/ throughputs- benefiting in particular from the advent of com- pact, high-power, relatively low- cost ...Award Number: W81XWH-15-1-0271 TITLE: Low- Cost , High-Throughput 3-D Pulmonary Imager Using Hyperpolarized Contrast Agents and Low-Field MRI...DISTRIBUTION STATEMENT: Approved for Public Release; Distribution Unlimited The views, opinions and/or findings contained in this report are those of the

  16. Low vision and mobility scooters: the experiences of individuals with low vision who use mobility scooters.

    Science.gov (United States)

    McMullan, Keri S; Butler, Mary

    2018-05-09

    Older adults with low vision are a growing population with rehabilitation needs including support with community mobility to enable community participation. Some older adults with low vision choose to use mobility scooters to mobilize within their community, but there is limited research about the use by people with low vision. This paper describes a pilot study and asks the question: what are the experiences of persons with low vision who use mobility scooters? This study gathered the experiences of four participants with low vision, aged 51 and over, who regularly use mobility scooters. Diverse methods were used including a go-along, a semi-structured interview and a new measure of functional vision for mobility called the vision-related outcomes in orientation and mobility (VROOM). Four themes were found to describe experiences: autonomy and well-being, accessibility, community interactions and self-regulation. Discussion and implications: This study was a pilot for a larger study examining self-regulation in scooter users. However, as roles emerge for health professionals and scooters, the findings also provide evidence to inform practice, because it demonstrates the complex meaning and influences on performance involved in low vision mobility scooter use. Implications for rehabilitation Scooter use supports autonomy and well-being and community connections for individuals with both mobility and visual impairments. Low vision scooter users demonstrate self-regulation of their scooter use to manage both their visual and environmental limitations. Issues of accessibility experienced by this sample affect a wider community of footpath users, emphasizing the need for councils to address inadequate infrastructure. Rehabilitators can support their low vision clients' scooter use by acknowledging issues of accessibility and promoting self-regulation strategies to manage risks and barriers.

  17. Math modeling for helicopter simulation of low speed, low altitude and steeply descending flight

    Science.gov (United States)

    Sheridan, P. F.; Robinson, C.; Shaw, J.; White, F.

    1982-01-01

    A math model was formulated to represent some of the aerodynamic effects of low speed, low altitude, and steeply descending flight. The formulation is intended to be consistent with the single rotor real time simulation model at NASA Ames Research Center. The effect of low speed, low altitude flight on main rotor downwash was obtained by assuming a uniform plus first harmonic inflow model and then by using wind tunnel data in the form of hub loads to solve for the inflow coefficients. The result was a set of tables for steady and first harmonic inflow coefficients as functions of ground proximity, angle of attack, and airspeed. The aerodynamics associated with steep descending flight in the vortex ring state were modeled by replacing the steady induced downwash derived from momentum theory with an experimentally derived value and by including a thrust fluctuations effect due to vortex shedding. Tables of the induced downwash and the magnitude of the thrust fluctuations were created as functions of angle of attack and airspeed.

  18. The effect of low temperature cryocoolers on the development of low temperature superconducting magnets

    International Nuclear Information System (INIS)

    Green, Michael A.

    2000-01-01

    The commercial development of reliable 4 K cryocoolers improves the future prospects for magnets made from low temperature superconductors (LTS). The hope of the developers of high temperature superconductors (HTS) has been to replace liquid helium cooled LTS magnets with HTS magnets that operate at or near liquid nitrogen temperature. There has been limited success in this endeavor, but continued problems with HTS conductors have greatly slowed progress toward this goal. The development of cryocoolers that reliably operate below 4 K will allow magnets made from LTS conductor to remain very competitive for many years to come. A key enabling technology for the use of low temperature cryocoolers on LTS magnets has been the development of HTS leads. This report describes the characteristics of LTS magnets that can be successfully melded to low-temperature cryocoolers. This report will also show when it is not appropriate to consider the use of low-temperature cryocoolers to cool magnets made with LTS conductor. A couple of specific examples of LTS magnets where cryocoolers can be used are given

  19. A University Consortium on Low Temperature Combustion for High Efficiency, Ultra-Low Emission Engines

    Energy Technology Data Exchange (ETDEWEB)

    Assanis, Dennis N. [Univ. of Michigan, Ann Arbor, MI (United States); Atreya, Arvind [Univ. of Michigan, Ann Arbor, MI (United States); Chen, Jyh-Yuan [Univ. of California, Berkeley, CA (United States); Cheng, Wai K. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Dibble, Robert W. [Univ. of California, Berkeley, CA (United States); Edwards, Chris [Stanford Univ., CA (United States); Filipi, Zoran S. [Univ. of Michigan, Ann Arbor, MI (United States); Gerdes, Christian [Stanford Univ., CA (United States); Im, Hong [Univ. of Michigan, Ann Arbor, MI (United States); Lavoie, George A. [Univ. of Michigan, Ann Arbor, MI (United States); Wooldridge, Margaret S. [Univ. of Michigan, Ann Arbor, MI (United States)

    2009-12-31

    The objective of the University consortium was to investigate the fundamental processes that determine the practical boundaries of Low Temperature Combustion (LTC) engines and develop methods to extend those boundaries to improve the fuel economy of these engines, while operating with ultra low emissions. This work involved studies of thermal effects, thermal transients and engine management, internal mixing and stratification, and direct injection strategies for affecting combustion stability. This work also examined spark-assisted Homogenous Charge Compression Ignition (HCCI) and exhaust after-treatment so as to extend the range and maximize the benefit of Homogenous Charge Compression Ignition (HCCI)/ Partially Premixed Compression Ignition (PPCI) operation. In summary the overall goals were; Investigate the fundamental processes that determine the practical boundaries of Low Temperature Combustion (LTC) engines; Develop methods to extend LTC boundaries to improve the fuel economy of HCCI engines fueled on gasoline and alternative blends, while operating with ultra low emissions; and Investigate alternate fuels, ignition and after-treatment for LTC and Partially Premixed compression Ignition (PPCI) engines.

  20. CpG island methylator phenotype-low (CIMP-low) colorectal cancer shows not only few methylated CIMP-high-specific CpG islands, but also low-level methylation at individual loci.

    Science.gov (United States)

    Kawasaki, Takako; Ohnishi, Mutsuko; Nosho, Katsuhiko; Suemoto, Yuko; Kirkner, Gregory J; Meyerhardt, Jeffrey A; Fuchs, Charles S; Ogino, Shuji

    2008-03-01

    The CpG island methylator phenotype (CIMP or CIMP-high) with widespread promoter methylation is a distinct phenotype in colorectal cancer. However, the concept of CIMP-low with less extensive CpG island methylation is still evolving. Our aim is to examine whether density of methylation in individual CpG islands was different between CIMP-low and CIMP-high tumors. Utilizing MethyLight technology and 889 population-based colorectal cancers, we quantified DNA methylation (methylation index, percentage of methylated reference) at 14 CpG islands, including 8 CIMP-high-specific loci (CACNA1G, CDKN2A (p16), CRABP1, IGF2, MLH1, NEUROG1, RUNX3 and SOCS1). Methylation positivity in each locus was defined as methylation index>4. Low-level methylation (methylation index>0, CIMP-high-specific locus was significantly more common in 340 CIMP-low tumors (1/8-5/8 methylation-positive loci) than 133 CIMP-high tumors (> or =6/8 methylation-positive loci) and 416 CIMP-0 tumors (0/8 methylation-positive loci) (PCIMP-high, low-level methylation, was not persistently more prevalent in CIMP-low tumors. In conclusion, compared to CIMP-high and CIMP-0 tumors, CIMP-low colorectal cancers show not only few methylated CIMP-high-specific CpG islands, but also more frequent low-level methylation at individual loci. Our data may provide supporting evidence for a difference in pathogenesis of DNA methylation between CIMP-low and CIMP-high tumors.

  1. Effect of weight loss by a low-fat diet and a low-carbohydrate diet on peptide YY levels.

    Science.gov (United States)

    Essah, P A; Levy, J R; Sistrun, S N; Kelly, S M; Nestler, J E

    2010-08-01

    To compare the effects of weight loss by an energy-restricted low-fat diet vs low-carbohydrate diet on serum peptide YY (PYY) levels. 8-Week prospective study of 30 obese adults (mean age: 42.8+/-2.0 years, mean body mass index 35.5+/-0.6 kg m(-2)). After 8 weeks, subjects on the low-carbohydrate diet lost substantially more weight than those on the low-fat diet (5.8 vs 0.99 kg, Plow-fat or low-carbohydrate diet likely represents a compensatory response to maintain energy homeostasis and contributes to difficulty in weight loss during energy-restricted diets.

  2. Effects of low doses

    International Nuclear Information System (INIS)

    Le Guen, B.

    2001-01-01

    Actually, even though it is comfortable for the risk management, the hypothesis of the dose-effect relationship linearity is not confirmed for any model. In particular, in the area of low dose rate delivered by low let emitters. this hypothesis is debated at the light of recent observations, notably these ones relative to the mechanisms leading to genetic instability and induction eventuality of DNA repair. The problem of strong let emitters is still to solve. (N.C.)

  3. Experiments on a low aspect ratio wing at low Reynolds numbers

    Science.gov (United States)

    Morse, Daniel R.

    At the start of the 21st century much of the focus of aircraft design has been turned to unmanned aerial vehicles (UAVs) which generally operate at much lower speeds in higher risk areas than manned aircraft. One subset of UAVs are Micro Air Vehicles (MAVs) which usually are no larger than 20cm and rely on non-traditional shapes to generate lift at very low velocities. This purpose of this work is to describe, in detail with experimental methods, the flow field around a low aspect ratio wing operating at low Reynolds numbers and at high angles of attack. Quantitative measurements are obtained by Three Component Time Resolved Particle Image Velocimetry (3C TR PIV) which describe the mean and turbulent flow field. This research focuses on the leading edge separation zone and the vortex shedding process which occurs at the leading edge. Streamwise wing tip vortices which dominate the lift characteristics are described with flow visualization and 3C TR PIV measurements. Turbulent Kinetic Energy (TKE) is described at the leading edge over several angles of attack. Turbulent Reynolds stresses in all three directions are described over the wing span and several Reynolds numbers. Two primary cyclic processes are observed within the flow field; one low frequency oscillation in the separated region and one high frequency event associated with leading edge vortex formation and convection. Two length scales are proposed and are shown to match well with each other, one based on leading edge vortex shedding frequency and convective velocity and the other based on mean vortex separation distance. A new method of rendering velocity frequency content over large data sets is proposed and used to illustrate the different frequencies observed at the leading edge.

  4. Low flow hydrology: a review

    CSIR Research Space (South Africa)

    Smakhtin, VU

    2001-01-10

    Full Text Available The paper intends to review the current status of low-flow hydrology — a discipline which deals with minimum flow in a river during the dry periods of the year. The discussion starts with the analysis of low-flow generating mechanisms operating...

  5. Thermal conductivity at very low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Locatelli, M [CEA Centre d' Etudes Nucleaires de Grenoble, 38 (France). Service des Basses Temperatures

    1976-06-01

    The interest of low and very low temperatures in solid physics and especially that of thermal measurements is briefly mentioned. Some notes on the thermal conductivity of dielectrics, the method and apparatus used to measure this property at very low temperatures (T<1.5K) and some recent results of fundamental and applied research are then presented.

  6. Strategies for Local Low-Carbon Development

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Nan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Price, Lynn [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fridley, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Ohshita, Stephanie [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Khanna, Nina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Min, Hu [Energy Foundation China, Beijing (China); Xiulian, Hu [Energy Research Inst., Beijing (China)

    2012-11-14

    Cities around the world are implementing policies and programs with the goal to reduce greenhouse gas emissions, as well as save energy, reduce costs, and protect the local, regional, and global environment. In China, low-carbon development is a key element of the 12th Five Year Plan. Pilot low-carbon development zones have been initiated in five provinces and eight cities and many other locations around China also want to pursue a low-carbon development pathway. This booklet provides information for government officials, policy makers, program designers and implementers, provincial and city planners, and others who want an overview of the key options available for low-carbon development at local level. These Strategies for Local Low-Carbon Development draw from successful experiences from around the world. Information is provided for low-carbon actions that can be taken in the sectors of (1) Industry, (2) Buildings and Appliances, (3) Electric Power, (4) Consumption and Waste Management, (5) Transportation and Urban Form, and (6) Agriculture and Forestry. A description of each policy is provided along with information on the stakeholders involved in implementation, the conditions for successful implementation, the expected energy and carbon savings, and the policy cost-effectiveness. Case studies show how each policy has been implemented somewhere around the world. While there are many low-carbon options available for local implementation, this booklet aims to provide guidance on those that have been most successful, that have the largest impact, and that are cost-effective in order to support low-carbon development efforts in Chinese cities.

  7. Advanced LIGO low-latency searches

    Science.gov (United States)

    Kanner, Jonah; LIGO Scientific Collaboration, Virgo Collaboration

    2016-06-01

    Advanced LIGO recently made the first detection of gravitational waves from merging binary black holes. The signal was first identified by a low-latency analysis, which identifies gravitational-wave transients within a few minutes of data collection. More generally, Advanced LIGO transients are sought with a suite of automated tools, which collectively identify events, evaluate statistical significance, estimate source position, and attempt to characterize source properties. This low-latency effort is enabling a broad multi-messenger approach to the science of compact object mergers and other transients. This talk will give an overview of the low-latency methodology and recent results.

  8. Adherence to low-carbohydrate and low-fat diets in relation to weight loss and cardiovascular risk factors.

    Science.gov (United States)

    Hu, Tian; Yao, Lu; Reynolds, Kristi; Niu, Tianhua; Li, Shengxu; Whelton, Paul K; He, Jiang; Steffen, Lyn M; Bazzano, Lydia A

    2016-03-01

    A low-carbohydrate diet can reduce body weight and some cardiovascular disease (CVD) risk factors more than a low-fat diet, but differential adherence may play a role in these effects. Data were used from 148 adults who participated in a 12-month clinical trial examining the effect of a low-carbohydrate diet (fat diet (fat, fat) on weight and CVD risk factors. We compared attendance at counseling sessions, deviation from nutrient goals, urinary ketone presence, and composite scores representing the overall adherence based on the distribution of these individual indicators between two interventions. Composite scores were similar between the two groups. A one-interquartile-range increase in composite score representing better adherence to a low-carbohydrate diet was associated with 2.2 kg or 2.3 % greater weight loss, 1.1 greater reduction in percent fat mass, and 1.3 greater increase in proportion of lean mass. Indicators of adherence to a low-fat diet was not associated with changes in weight, fat mass or lean mass. Despite comparable adherence between groups, a low-carbohydrate diet was associated with greater reductions in body weight and improvement in body composition, while a low-fat diet was not associated with weight loss.

  9. Acupuncture or low frequency infrared treatment for low back pain in Chinese patients: a discrete choice experiment.

    Directory of Open Access Journals (Sweden)

    Li-Chia Chen

    Full Text Available Acupuncture is a popular but controversial treatment option for low back pain. In China, it is practised as traditional Chinese medicine; other treatment strategies for low back pain are commonly practised as Western medicine. Research on patient preference for low back-pain treatment options has been mainly conducted in Western countries and is limited to a willingness-to-pay approach. A stated-preference, discrete choice experiment was conducted to determine Chinese patient preferences and trade-offs for acupuncture and low frequency infrared treatment in low back pain from September 2011 to August 2012 after approval from the Department of Scientific Research in the study settings. Eight-six adult outpatients who visited the 'traditional medicine department' at a traditional Chinese medicine hospital and the 'rehabilitation department' at a Western medicine hospital in Guangdong Province of China for chronic low back pain during study period participated in an interview survey. A questionnaire containing 10 scenarios (5 attributes in each scenario was used to ask participants' preference for acupuncture, low frequency infrared treatment or neither option. Validated responses were analysed using a nested-logit model. The decision on whether to receive a therapy was not associated with the expected utility of receiving therapy, female gender and higher out-of-pocket payment significantly decreased chance to receive treatments. Of the utility of receiving either acupuncture or low frequency infrared treatment, the treatment sensation was the most important attribute as an indicator of treatment efficacy, followed by the maximum efficacy, maintenance duration and onset of efficacy, and the out-of-pocket payment. The willingness-to-pay for acupuncture and low frequency infrared treatment were about $618.6 and $592.4 USD per course respectively, demonstrated patients' demand of pain management. The treatment sensation was regarded as an indicator

  10. Scenarios for low carbon and low water electric power plant ...

    Science.gov (United States)

    In the water-energy nexus, water use for the electric power sector is critical. Currently, the operational phase of electric power production dominates the electric sector's life cycle withdrawal and consumption of fresh water resources. Water use associated with the fuel cycle and power plant equipment manufacturing phase is substantially lower on a life cycle basis. An outstanding question is: how do regional shifts to lower carbon electric power mixes affect the relative contribution of the upstream life cycle water use? To test this, we examine a range of scenarios comparing a baseline with scenarios of carbon reduction and water use constraints using the MARKet ALlocation (MARKAL) energy systems model with ORD's 2014 U.S. 9-region database (EPAUS9r). The results suggest that moving toward a low carbon and low water electric power mix may increase the non-operational water use. In particular, power plant manufacturing water use for concentrating solar power, and fuel cycle water use for biomass feedstock, could see sharp increases under scenarios of high deployment of these low carbon options. Our analysis addresses the following questions. First, how does moving to a lower carbon electricity generation mix affect the overall regional electric power water use from a life cycle perspective? Second, how does constraining the operational water use for power plants affect the mix, if at all? Third, how does the life cycle water use differ among regions under

  11. Mitochondrial-Derived Oxidants and Cellular Responses to Low Dose/Low LET Ionizing Radiation

    International Nuclear Information System (INIS)

    Spitz, Douglas R.

    2009-01-01

    Exposure to ionizing radiation results in the immediate formation of free radicals and other reactive oxygen species (ROS). It has been assumed that the subsequent injury processes leading to genomic instability and carcinogenesis following radiation, derive from the initial oxidative damage caused by these free radicals and ROS. It is now becoming increasingly obvious that metabolic oxidation/reduction (redox) reactions can be altered by irradiation leading to persistent increases in steady-state levels of intracellular free radicals and ROS that contribute to the long term biological effects of radiation exposure by causing chronic oxidative stress. The objective during the last period of support (DE-FG02-05ER64050; 5/15/05-12/31/09) was to determine the involvement of mitochondrial genetic defects in metabolic oxidative stress and the biological effects of low dose/low LET radiation. Aim 1 was to determine if cells with mutations in succinate dehydrogenase (SDH) subunits C and D (SDHC and SDHD in mitochondrial complex II) demonstrated increases in steady-state levels of reactive oxygen species (ROS; O 2 - and H 2 O 2 ) as well as demonstrating increased sensitivity to low dose/low LET radiation (10 cGy) in cultured mammalian cells. Aim No.2 was to determine if mitochondrially-derived ROS contributed to increased sensitivity to low dose/low LET radiation in mammalian cells containing mutations in SDH subunits. Aim No.3 was to determine if a causal relationship existed between increases in mitochondrial ROS production, alterations in electron transport chain proteins, and genomic instability in the progeny of irradiated cells. Evidence gathered in the 2005-2009 period of support demonstrated that mutations in genes coding for mitochondrial electron transport chain proteins (ETC); either Succinate Dehydrogenase (SDH) subunit C (SDHC) or subunit D (SDHD); caused increased ROS production, increased genomic instability, and increased sensitivity to low dose/low LET

  12. The low-current low-temperature plasma generators

    International Nuclear Information System (INIS)

    Dautov, G.Yu.

    2000-01-01

    In this article, the results of low-current gas-discharge plasma generator investigations carried out by a group of scientists from the Kazan' Aviation Institute are presented. When considered necessary, the results are compared with the data obtained by other authors. The basic configurations and theoretical calculation peculiarities of plasma generators are described. The electrical, thermal and energy characteristics of discharges in gas flows, as well as summarised empirical formulae and experimental data necessary for calculations and design of plasma devices are presented. (author)

  13. Low-Cost, High-Throughput 3-D Pulmonary Imager Using Hyperpolarized Contrast Agents and Low-Field MRI

    Science.gov (United States)

    2017-10-01

    low- cost and high-throughput was a key element proposed for this project, which we believe will be of significant benefit to the patients suffering...Award Number: W81XWH-15-1-0272 TITLE: Low- Cost , High-Throughput 3-D Pulmonary Imager Using Hyperpolarized Contrast Agents and Low-Field MRI...STATEMENT: Approved for Public Release; Distribution Unlimited The views, opinions and/or findings contained in this report are those of the author(s

  14. Bootstrapped Low-Voltage Analog Switches

    DEFF Research Database (Denmark)

    Steensgaard-Madsen, Jesper

    1999-01-01

    Novel low-voltage constant-impedance analog switch circuits are proposed. The switch element is a single MOSFET, and constant-impedance operation is obtained using simple circuits to adjust the gate and bulk voltages relative to the switched signal. Low-voltage (1-volt) operation is made feasible...

  15. In-Situ Microprobe Observations of Dispersed Oil with Low-Temperature Low-Vacuum Scanning Electron Microscope

    International Nuclear Information System (INIS)

    Mohsen, H.T.

    2010-01-01

    A low cost cryostat stage from high heat capacity material is designed and constructed, in attempt to apply size distribution techniques for examination of oil dispersions. Different materials were tested according to their heat capacity to keep the liquid under investigation in frozen state as long as possible during the introduction of the cryostat stage to the low-vacuum scanning electron microscope. Different concentrations of non ionic surfactant were added to artificially contaminated with 10000 ppm Balayeam base oil in 3.5 % saline water, where oil and dispersing liquid have been added and shacked well to be investigated under the microscope as fine frozen droplets. The efficiency of dispersion was examined using low temperature low-vacuum scanning electron microscope. The shape and size distributions of freeze oil droplets were studied by digital imaging processing technique in conjunction with scanning electron microscope counting method. Also elemental concentration of oil droplets was analyzed.

  16. Low emittance photoinjectors

    International Nuclear Information System (INIS)

    Ferrario, Massimo

    2001-01-01

    Photon colliders require high charge polarized electron beams with very low normalized emittances, possibly lower than the actual damping rings design goals. Recent analytical and numerical efforts in understanding beam dynamics in RF photoinjectors have raised again the question as to whether the performances of an RF electron gun based injector could be competitive with respect to a damping ring. As a matter of discussion we report in this paper the most recent results concerning low emittance photoinjector designs: the production of polarized electron beams by DC and/or RF guns is illustrated together with space charge compensation techniques and thermal emittance effects. New ideas concerning multi-gun injection system and generation of flat beams by RF gun are also discussed

  17. Track structure analysis illustrating the prominent role of low-energy electrons in radiobiological effects of low-LET radiations

    International Nuclear Information System (INIS)

    Nikjoo, H.; Goodhead, D.T.

    1991-01-01

    Monte Carlo track structure methods have been used to illustrate the importance of low-energy electrons produced by low-LET radiations. It is shown that these low-energy secondary electrons contribute substantially to the dose in all low-LET irradiations and are particularly efficient at producing highly localized clusters of atomic damage which may be responsible for a major part of the biological effectiveness of low-LET radiations. The data generated by Monte Carlo track structure techniques and by earlier semi-analytical methods based on the LET concept have been compared in terms of cumulative and differential fractions of total dose absorbed as a function of electron energy. The data show that low-energy secondary electrons account for up to nearly 50% of the total dose imparted to a medium when irradiated with electrons or photons. (author)

  18. Learning Low-Dimensional Metrics

    OpenAIRE

    Jain, Lalit; Mason, Blake; Nowak, Robert

    2017-01-01

    This paper investigates the theoretical foundations of metric learning, focused on three key questions that are not fully addressed in prior work: 1) we consider learning general low-dimensional (low-rank) metrics as well as sparse metrics; 2) we develop upper and lower (minimax)bounds on the generalization error; 3) we quantify the sample complexity of metric learning in terms of the dimension of the feature space and the dimension/rank of the underlying metric;4) we also bound the accuracy ...

  19. Low temperatures - hot topic

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1988-09-15

    Neutrino mass measurements, next-generation double beta experiments, solar neutrino detection, searches for magnetic monopoles and the challenge of discovering what most of the Universe is made of (dark matter), not to mention axions (cosmic and solar), supersymmetric neutral particles and cosmic neutrinos. All this physics could use cryogenic techniques. Thus the second European Workshop on Low Temperature Devices for the Detection of Low Energy Neutrinos and Dark Matter, held at LAPP (Annecy) in May, covered an active and promising field.

  20. Low temperatures - hot topic

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    Neutrino mass measurements, next-generation double beta experiments, solar neutrino detection, searches for magnetic monopoles and the challenge of discovering what most of the Universe is made of (dark matter), not to mention axions (cosmic and solar), supersymmetric neutral particles and cosmic neutrinos. All this physics could use cryogenic techniques. Thus the second European Workshop on Low Temperature Devices for the Detection of Low Energy Neutrinos and Dark Matter, held at LAPP (Annecy) in May, covered an active and promising field

  1. Job satisfaction in a low-wage, low-status industry: The case of Danish food retailing

    DEFF Research Database (Denmark)

    Esbjerg, Lars; Grunert, Klaus G.; Buck, Nuka

    This paper explains why job satisfaction is high among employees in Danish food retailing - a low-wage, low-status industry. We distinguish between three employee types (transitional workers, core employees and career-seekers) and identify factors such as divergent interests and ambitions to help...

  2. Low-Gain, Low-Noise Integrated Neuronal Amplifier for Implantable Artifact-Reduction Recording System

    OpenAIRE

    Zbrzeski, Adeline; Lewis, Noëlle; Rummens, Francois; Jung, Ranu; N'Kaoua, Gilles; Benazzouz, Abdelhamid; Renaud, Sylvie

    2013-01-01

    Brain neuroprostheses for neuromodulation are being designed to monitor the neural activity of the brain in the vicinity of the region being stimulated using a single macro-electrode. Using a single macro-electrode, recent neuromodulation studies show that recording systems with a low gain neuronal amplifier and successive amplifier stages can reduce or reject stimulation artifacts. These systems were made with off-the-shelf components that are not amendable for future implant design. A low-g...

  3. Directions in low-level radioactive waste management: A brief history of commercial low-level radioactive waste disposal

    International Nuclear Information System (INIS)

    1994-08-01

    This report presents a history of commercial low-level radioactive waste disposal in the United States, with emphasis on the history of six commercially operated low-level radioactive waste disposal facilities. The report includes a brief description of important steps that have been taken during the last decade to ensure the safe disposal of low-level radioactive waste in the 1990s and beyond. These steps include the issuance of comprehensive State and Federal regulations governing the disposal of low-level radioactive waste, and the enactment of Federal laws making States responsible for the disposal of such waste generated within their borders

  4. Inside bluetooth low energy

    CERN Document Server

    Gupta, Naresh

    2013-01-01

    Bluetooth Low Energy (LE) is one of the latest enhancement to Bluetooth technology and, as the name suggests, it is aimed at ultra low power devices, such as heart rate monitors, thermometers, and sensors. Due to very low power consumption, devices compliant with this standard can operate for several years on coin cell batteries without the need for recharging. This cutting-edge book helps you understand the whats , whys , and hows of Bluetooth LE. It includes a broad view of the technology, identifies the various building blocks, and explains how they come together. You also find discussions on Bluetooth basics, providing the background information needed to master Bluetooth LE.The book explains the architecture of Bluetooth LE stack and the functionality provided by each of the layers. You find expert guidance in setting up your own system in a quick and efficient manner with inexpensive, easily available hardware and just a couple of PCs running Linux. This unique volume features two chapters that are dedi...

  5. Low level waste disposal

    International Nuclear Information System (INIS)

    Barthoux, A.

    1985-01-01

    Final disposal of low level wastes has been carried out for 15 years on the shallow land disposal of the Manche in the north west of France. Final participant in the nuclear energy cycle, ANDRA has set up a new waste management system from the production center (organization of the waste collection) to the disposal site including the setting up of a transport network, the development of assessment, additional conditioning, interim storage, the management of the disposal center, records of the location and characteristics of the disposed wastes, site selection surveys for future disposals and a public information Department. 80 000 waste packages representing a volume of 20 000 m 3 are thus managed and disposed of each year on the shallow land disposal. The disposal of low level wastes is carried out according to their category and activity level: - in tumuli for very low level wastes, - in monoliths, a concrete structure, of the packaging does not provide enough protection against radioactivity [fr

  6. Very low energy geothermics

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    Very low energy geothermics correspond to temperatures below 30 C and has been developed to cover heating and cooling needs of recent individual houses or tertiary industries using heat pumps and low depth aquifers (<100 m). Geothermal heat pumps industry has made great strides in European Northern countries, China, Japan and the United States of America. Geothermal heat pumps are less energy consuming than air heat pumps and require less cooling fluid and maintenance. The Aquapac procedure has been developed in France in 1983 by the AFME (French Energy Control Agency), EdF and the BRGM (Geologic and Mining Research Office) to encourage the use of geothermal heat pump for domestic and sanitary water heating and to make a survey of low-depth aquifers in the whole french territory. The decay of energy costs that started in 1986 has led to a loss of interest for the Aquapac procedure, even in the tertiary industries for which the air-conditioning demand is growing up. (J.S.). 1 tab

  7. Carcinogenesis induced by low-dose radiation

    Directory of Open Access Journals (Sweden)

    Piotrowski Igor

    2017-11-01

    Full Text Available Although the effects of high dose radiation on human cells and tissues are relatively well defined, there is no consensus regarding the effects of low and very low radiation doses on the organism. Ionizing radiation has been shown to induce gene mutations and chromosome aberrations which are known to be involved in the process of carcinogenesis. The induction of secondary cancers is a challenging long-term side effect in oncologic patients treated with radiation. Medical sources of radiation like intensity modulated radiotherapy used in cancer treatment and computed tomography used in diagnostics, deliver very low doses of radiation to large volumes of healthy tissue, which might contribute to increased cancer rates in long surviving patients and in the general population. Research shows that because of the phenomena characteristic for low dose radiation the risk of cancer induction from exposure of healthy tissues to low dose radiation can be greater than the risk calculated from linear no-threshold model. Epidemiological data collected from radiation workers and atomic bomb survivors confirms that exposure to low dose radiation can contribute to increased cancer risk and also that the risk might correlate with the age at exposure.

  8. Beam diagnostics for low energy beams

    Directory of Open Access Journals (Sweden)

    J. Harasimowicz

    2012-12-01

    Full Text Available Low-energetic ion and antimatter beams are very attractive for a number of fundamental studies. The diagnostics of such beams, however, is a challenge due to low currents down to only a few thousands of particles per second and significant fraction of energy loss in matter at keV beam energies. A modular set of particle detectors has been developed to suit the particular beam diagnostic needs of the ultralow-energy storage ring (USR at the future facility for low-energy antiproton and ion research, accommodating very low beam intensities at energies down to 20 keV. The detectors include beam-profile monitors based on scintillating screens and secondary electron emission, sensitive Faraday cups for absolute intensity measurements, and capacitive pickups for beam position monitoring. In this paper, the design of all detectors is presented in detail and results from beam measurements are shown. The resolution limits of all detectors are described and options for further improvement summarized. Whilst initially developed for the USR, the instrumentation described in this paper is also well suited for use in other low-intensity, low-energy accelerators, storage rings, and beam lines.

  9. From MAD to SAD: The Italian experience for the low-frequency aperture array of SKA1-LOW

    Science.gov (United States)

    Bolli, P.; Pupillo, G.; Virone, G.; Farooqui, M. Z.; Lingua, A.; Mattana, A.; Monari, J.; Murgia, M.; Naldi, G.; Paonessa, F.; Perini, F.; Pluchino, S.; Rusticelli, S.; Schiaffino, M.; Schillirò, F.; Tartarini, G.; Tibaldi, A.

    2016-03-01

    This paper describes two small aperture array demonstrators called Medicina and Sardinia Array Demonstrators (MAD and SAD, respectively). The objectives of these instruments are to acquire experience and test new technologies for a possible application to the low-frequency aperture array of the low-frequency telescope of the Square Kilometer Array phase 1 (SKA1-LOW). The MAD experience was concluded in 2014, and it turned out to be an important test bench for implementing calibration techniques based on an artificial source mounted in an aerial vehicle. SAD is based on 128 dual-polarized Vivaldi antennas and is 1 order of magnitude larger than MAD. The architecture and the station size of SAD, which is along the construction phase, are more similar to those under evaluation for SKA1-LOW, and therefore, SAD is expected to provide useful hints for SKA1-LOW.

  10. Single-Phase Hybrid Switched Reluctance Motor for Low-Power Low-Cost Applications

    DEFF Research Database (Denmark)

    Lu, Kaiyuan; Rasmussen, Peter Omand; Jakobsen, Uffe

    2011-01-01

    This paper presents a new single-phase, Hybrid Switched Reluctance (HSR) motor for low-cost, low-power, pump or fan drive systems. Its single-phase configuration allows use of a simple converter to reduce the system cost. Cheap ferrite magnets are used and arranged in a special flux concentration...... manner to increase effectively the torque density and efficiency of this machine. The efficiency of this machine is comparable to the efficiency of a traditional permanent magnet machine in the similar power range. The cogging torque, due to the existence of the permanent magnetic field, is beneficially...

  11. Crossing-symmetric solutions to low equations

    International Nuclear Information System (INIS)

    McLeod, R.J.; Ernst, D.J.

    1985-01-01

    Crossing symmetric models of the pion-nucleon interaction in which crossing symmetry is kept to lowest order in msub(π)/msub(N) are investigated. Two iterative techniques are developed to solve the crossing-symmetric Low equation. The techniques are used to solve the original Chew-Low equations and their generalizations to include the coupling to the pion-production channels. Small changes are found in comparison with earlier results which used an iterative technique proposed by Chew and Low and which did not produce crossing-symmetric results. The iterative technique of Chew and Low is shown to fail because of its inability to produce zeroes in the amplitude at complex energies while physical solutions to the model require such zeroes. We also prove that, within the class of solutions such that phase shifts approach zero for infinite energy, the solution to the Low equation is unique. (orig.)

  12. Low potassium level

    Science.gov (United States)

    ... treat and prevent low level of potassium. These foods include: Avocados Baked potato Bananas Bran Carrots Cooked lean beef Milk Oranges Peanut butter Peas and beans Salmon Seaweed Spinach Tomatoes Wheat germ

  13. Update on low-level waste compacts and state agencies

    International Nuclear Information System (INIS)

    Tenan, M.; Rabbe, D.; Thompson, P.

    1995-01-01

    This article updates information on the following agencies involved in low-level radioactive wastes: Appalachian States Low-Level Radioactive Waste Commission; Central Interstate Low-Level radioactive Waste Commission; Central Midwest Interstate Low-Level radioactive Waste Compact; Massachusetts Low-Level radioactive Waste Management Board; Michigan Low-Level Radioactive Waste Authority; Midwest Interstate Low-Level Radioactive Waste Commission; New York State Low-Level Radioactive Waste Siting Commission; Northeast Interstate Low-Level Radioactive Waste Compact; Northwest Interstate Compact on Low-Level Radioactive Waste Management; Rocky Mountain Low-Level Radioactive Waste Board; Southeast Compact Commission for Low-Level Radioactive Waste Management;Southwest Low-Level Radioactive Waste Commission; Texas Low-Level Radioactive Waste Disposal Authority

  14. Improved Low Temperature Performance of Supercapacitors

    Science.gov (United States)

    Brandon, Erik J.; West, William C.; Smart, Marshall C.; Gnanaraj, Joe

    2013-01-01

    Low temperature double-layer capacitor operation enabled by: - Base acetonitrile / TEATFB salt formulation - Addition of low melting point formates, esters and cyclic ethers center dot Key electrolyte design factors: - Volume of co-solvent - Concentration of salt center dot Capacity increased through higher capacity electrodes: - Zeolite templated carbons - Asymmetric cell designs center dot Continuing efforts - Improve asymmetric cell performance at low temperature - Cycle life testing Motivation center dot Benchmark performance of commercial cells center dot Approaches for designing low temperature systems - Symmetric cells (activated carbon electrodes) - Symmetric cells (zeolite templated carbon electrodes) - Asymmetric cells (lithium titanate/activated carbon electrodes) center dot Experimental results center dot Summary

  15. Solar-assisted low energy dwellings

    Energy Technology Data Exchange (ETDEWEB)

    Esbensen, T V

    1980-02-01

    The Zero Energy House Group was formed as a subproject of the CCMS Solar Energy Pilot Study in 1974 by seven participating countries experimenting with solar-assisted low-energy dwellings for temperate and northern European climatic conditions. A Zero Energy House is one in which solar energy is used to meet the reduced energy needs of buildings incorporating various thermal energy conservation features. This final report of the Zero Energy House Group includes brief descriptions of 13 major low-energy dwellings in the participating CCMS countries. An overall assessment of the state-of-the-art in solar-assisted low-energy dwellings is also included.

  16. Low-Dose Tramadol and Non-Steroidal Anti-Inflammatory Drug Combination Therapy Prevents the Transition to Chronic Low Back Pain.

    Science.gov (United States)

    Inage, Kazuhide; Orita, Sumihisa; Yamauchi, Kazuyo; Suzuki, Takane; Suzuki, Miyako; Sakuma, Yoshihiro; Kubota, Go; Oikawa, Yasuhiro; Sainoh, Takeshi; Sato, Jun; Fujimoto, Kazuki; Shiga, Yasuhiro; Abe, Koki; Kanamoto, Hirohito; Inoue, Masahiro; Kinoshita, Hideyuki; Takahashi, Kazuhisa; Ohtori, Seiji

    2016-08-01

    Retrospective study. To determine whether low-dose tramadol plus non-steroidal anti-inflammatory drug combination therapy could prevent the transition of acute low back pain to chronic low back pain. Inadequately treated early low back pain transitions to chronic low back pain occur in approximately 30% of affected individuals. The administration of non-steroidal anti-inflammatory drugs is effective for treatment of low back pain in the early stages. However, the treatment of low back pain that is resistant to non-steroidal anti-inflammatory drugs is challenging. Patients who presented with acute low back pain at our hospital were considered for inclusion in this study. After the diagnosis of acute low back pain, non-steroidal anti-inflammatory drug administration was started. Forty patients with a visual analog scale score of >5 for low back pain 1 month after treatment were finally enrolled. The first 20 patients were included in a non-steroidal anti-inflammatory drug group, and they continued non-steroidal anti-inflammatory drug therapy for 1 month. The next 20 patients were included in a combination group, and they received low-dose tramadol plus non-steroidal anti-inflammatory drug combination therapy for 1 month. The incidence of adverse events and the improvement in the visual analog scale score at 2 months after the start of treatment were analyzed. No adverse events were observed in the non-steroidal anti-inflammatory drug group. In the combination group, administration was discontinued in 2 patients (10%) due to adverse events immediately following the start of tramadol administration. At 2 months, the improvement in the visual analog scale score was greater in the combination group than in the non-steroidal anti-inflammatory drug group (ppain to chronic low back pain.

  17. MOCA: A Low-Power, Low-Cost Motion Capture System Based on Integrated Accelerometers

    Directory of Open Access Journals (Sweden)

    Elisabetta Farella

    2007-01-01

    Full Text Available Human-computer interaction (HCI and virtual reality applications pose the challenge of enabling real-time interfaces for natural interaction. Gesture recognition based on body-mounted accelerometers has been proposed as a viable solution to translate patterns of movements that are associated with user commands, thus substituting point-and-click methods or other cumbersome input devices. On the other hand, cost and power constraints make the implementation of a natural and efficient interface suitable for consumer applications a critical task. Even though several gesture recognition solutions exist, their use in HCI context has been poorly characterized. For this reason, in this paper, we consider a low-cost/low-power wearable motion tracking system based on integrated accelerometers called motion capture with accelerometers (MOCA that we evaluated for navigation in virtual spaces. Recognition is based on a geometric algorithm that enables efficient and robust detection of rotational movements. Our objective is to demonstrate that such a low-cost and a low-power implementation is suitable for HCI applications. To this purpose, we characterized the system from both a quantitative point of view and a qualitative point of view. First, we performed static and dynamic assessment of movement recognition accuracy. Second, we evaluated the effectiveness of user experience using a 3D game application as a test bed.

  18. Low-Gain, Low-Noise Integrated Neuronal Amplifier for Implantable Artifact-Reduction Recording System

    Directory of Open Access Journals (Sweden)

    Abdelhamid Benazzouz

    2013-09-01

    Full Text Available Brain neuroprostheses for neuromodulation are being designed to monitor the neural activity of the brain in the vicinity of the region being stimulated using a single macro-electrode. Using a single macro-electrode, recent neuromodulation studies show that recording systems with a low gain neuronal amplifier and successive amplifier stages can reduce or reject stimulation artifacts. These systems were made with off-the-shelf components that are not amendable for future implant design. A low-gain, low-noise integrated neuronal amplifier (NA with the capability of recording local field potentials (LFP and spike activity is presented. In vitro and in vivo characterizations of the tissue/electrode interface, with equivalent impedance as an electrical model for recording in the LFP band using macro-electrodes for rodents, contribute to the NA design constraints. The NA occupies 0.15 mm2 and dissipates 6.73 µW, and was fabricated using a 0.35 µm CMOS process. Test-bench validation indicates that the NA provides a mid-band gain of 20 dB and achieves a low input-referred noise of 4 µVRMS. Ability of the NA to perform spike recording in test-bench experiments is presented. Additionally, an awake and freely moving rodent setup was used to illustrate the integrated NA ability to record LFPs, paving the pathway for future implantable systems for neuromodulation.

  19. Factors associated with choice of a low-fat or low-carbohydrate diet during a behavioral weight loss intervention.

    Science.gov (United States)

    McVay, Megan A; Voils, Corrine I; Coffman, Cynthia J; Geiselman, Paula J; Kolotkin, Ronette L; Mayer, Stephanie B; Smith, Valerie A; Gaillard, Leslie; Turner, Marsha J; Yancy, William S

    2014-12-01

    Individuals undertaking a weight loss effort have a choice among proven dietary approaches. Factors contributing to choice of either a low-fat/low-calorie diet or a low-carbohydrate diet, two of the most studied and popular dietary approaches, are unknown. The current study used data from participants randomized to the 'choice' arm of a trial examining whether being able to choose a diet regimen yields higher weight loss than being randomly assigned to a diet. At study entry, participants attended a group session during which they were provided tailored feedback indicating which diet was most consistent with their food preferences using the Geiselman Food Preference Questionnaire (FPQ), information about both diets, and example meals for each diet. One week later, they indicated which diet they chose to follow during the 48-week study, with the option of switching diets after 12 weeks. Of 105 choice arm participants, 44 (42%) chose the low-fat/low-calorie diet and 61 (58%) chose the low-carbohydrate diet. In bivariate analyses, diet choice was not associated with age, race, sex, education, BMI, or diabetes (all p > 0.05). Low-carbohydrate diet choice was associated with baseline higher percent fat intake (p = 0.007), lower percent carbohydrate intake (p = 0.02), and food preferences consistent with a low-carbohydrate diet according to FPQ (p model, only FPQ diet preference was associated with diet choice (p = 0.001). Reported reasons for diet choice were generally similar for those choosing either diet; however, concerns about negative health effects of the unselected diet was rated as more influential among participants selecting the low-fat diet. Only three low-carbohydrate and two low-fat diet participants switched diets at 12 weeks. Results suggest that when provided a choice between two popular weight loss dietary approaches, an individual's selection is likely influenced by baseline dietary intake pattern, and especially by his or her

  20. Rural Low-Wage Employment Rises among Men.

    Science.gov (United States)

    Gibbs, Robert; Parker, Timothy

    2000-01-01

    In 1999, the percentage of low-wage workers in rural areas was higher than in urban areas or in 1979. The share of women and minorities in low-wage work stabilized, but the share of White men increased. Low-wage work increased in higher-skilled occupations, and the share of college educated low-wage workers increased significantly since 1979. (TD)

  1. Performance study on a low-temperature absorption–compression cascade refrigeration system driven by low-grade heat

    International Nuclear Information System (INIS)

    Xu, Yingjie; Chen, Guangming; Wang, Qin; Han, Xiaohong; Jiang, Ning; Deng, Shiming

    2016-01-01

    Highlights: • An absorption–compression system for low-temperature is developed and analyzed. • Cooling capacity, compression power, and discharge temperature are all improved. • At −170 °C, giving 200 W low-grade cooling capacity, COP increases by 28.6%. • Simulation results are verified experimentally, showing good agreement. - Abstract: This paper presents a performance study on a low-temperature absorption–compression cascade refrigeration system (LACRS), which consists of an absorption subsystem (AS) and a vapor compression auto-cascade subsystem (CS). In the system, low-grade heat of AS is used to subcool the CS, which can obtain cold energy at −170 °C. A simulation study is carried out to investigate the effects of evaporating temperature and low-grade cooling capacity on system performance. The study results show that as low-grade cooling capacity from the AS is provided to the CS, high-grade cooling capacity increases, compressor power consumption decreases, and the COP of the CS therefore increases. Comparing with compression auto-cascade cycle, the largest COP improvement of LACRS is about 38%. The model is verified by experimental data. An additional high-grade cooling capacity is obtained experimentally at −170 °C. The study results presented in this paper not only demonstrate the excellent performance of the LACRS, but also provide important guidance to further system design, and practical application.

  2. An ultra-low power output capacitor-less low-dropout regulator with slew-rate-enhanced circuit

    Science.gov (United States)

    Cheng, Xin; Zhang, Yu; Xie, Guangjun; Yang, Yizhong; Zhang, Zhang

    2018-03-01

    An ultra-low power output-capacitorless low-dropout (LDO) regulator with a slew-rate-enhanced (SRE) circuit is introduced. The increased slew rate is achieved by sensing the transient output voltage of the LDO and then charging (or discharging) the gate capacitor quickly. In addition, a buffer with ultra-low output impedance is presented to improve line and load regulations. This design is fabricated by SMIC 0.18 μm CMOS technology. Experimental results show that, the proposed LDO regulator only consumes an ultra-low quiescent current of 1.2 μA. The output current range is from 10 μA to 200 mA and the corresponding variation of output voltage is less than 40 mV. Moreover, the measured line regulation and load regulation are 15.38 mV/V and 0.4 mV/mA respectively. Project supported by the National Natural Science Foundation of China (Nos. 61401137, 61404043, 61674049).

  3. Urbanization of black South African women may increase risk of low bone mass due to low vitamin D status, low calcium intake and high bone turnover

    OpenAIRE

    Kruger, Annamarie; Kruger, Marlena C.; Kruger, Iolanthé Marike; Wentzel-Viljoen, Edelweiss

    2011-01-01

    Globally, rural to urban migration is accompanied by changes in dietary patterns and lifestyle that have serious health implications, including development of low bone mass. We hypothesized that serum 25 (OH) vitamin D3 (25[OH]D3) levels will be lower, bone turnover higher, and nutrition inadequate in urban postmenopausal black women, increasing risk for low bone mass. We aimed to assess the prevalence of risk factors for low bone mass in 1261 black women from rural and urban areas in the Nor...

  4. Scenarios for low carbon and low water electric power plant operations: implications for upstream water use

    Data.gov (United States)

    U.S. Environmental Protection Agency — The dataset includes all data used in the creation of figures and graphs in the paper: "Scenarios for low carbon and low water electric power plant operations:...

  5. Low-temperature thermal expansion

    International Nuclear Information System (INIS)

    Collings, E.W.

    1986-01-01

    This chapter discusses the thermal expansion of insulators and metals. Harmonicity and anharmonicity in thermal expansion are examined. The electronic, magnetic, an other contributions to low temperature thermal expansion are analyzed. The thermodynamics of the Debye isotropic continuum, the lattice-dynamical approach, and the thermal expansion of metals are discussed. Relative linear expansion at low temperatures is reviewed and further calculations of the electronic thermal expansion coefficient are given. Thermal expansions are given for Cu, Al and Ti. Phenomenologic thermodynamic relationships are also discussed

  6. Programmable, very low noise current source

    Science.gov (United States)

    Scandurra, G.; Cannatà, G.; Giusi, G.; Ciofi, C.

    2014-12-01

    We propose a new approach for the realization of very low noise programmable current sources mainly intended for application in the field of low frequency noise measurements. The design is based on a low noise Junction Field Effect Transistor (JFET) acting as a high impedance current source and programmability is obtained by resorting to a low noise, programmable floating voltage source that allows to set the sourced current at the desired value. The floating voltage source is obtained by exploiting the properties of a standard photovoltaic MOSFET driver. Proper filtering and a control network employing super-capacitors allow to reduce the low frequency output noise to that due to the low noise JFET down to frequencies as low as 100 mHz while allowing, at the same time, to set the desired current by means of a standard DA converter with an accuracy better than 1%. A prototype of the system capable of supplying currents from a few hundreds of μA up to a few mA demonstrates the effectiveness of the approach we propose. When delivering a DC current of about 2 mA, the power spectral density of the current fluctuations at the output is found to be less than 25 pA/√Hz at 100 mHz and less than 6 pA/√Hz for f > 1 Hz, resulting in an RMS noise in the bandwidth from 0.1 to 10 Hz of less than 14 pA.

  7. Estimates of Health Detriments and Tissue Weighting Factors for Hong Kong Populations from Low Dose, Low Dose Rate and Low LET Ionising Radiation Exposure

    International Nuclear Information System (INIS)

    Lee, S.K.

    1998-01-01

    The total health detriments and the tissue weighting factors for the Hong Kong populations from low dose, low dose rate and low LET ionising radiation exposure are obtained according to the methodology recommended in ICRP Publication 60. The probabilities of fatal cancers for the general (ages 0-90) and working (ages 20-64) populations due to lifetime exposure at low dose and low dose rate are 4.9 x 10 -2 Sv -1 and 3.6 x 10 -2 Sv -1 respectively, comparing with the ICRP 60 estimates of 5.0 x 10 -2 Sv -1 and 4.0 x 10 -2 Sv -1 . The corresponding total health detriments for the general and working populations are 6.9 x 10 -2 Sv -1 and 4.9 x 10 -2 Sv -1 respectively comparing with the ICRP 60 estimates of 7.3 x 10 -2 Sv -1 and 5.6 x 10 -2 Sv -1 . Tissue weighting factors for the general population are 0.01 (bone surface and skin), 0.02 (liver, oesophagus and thyroid), 0.04 (bladder and breast), 0.08 (remainder), 0.10 (stomach), 0.11 (bone marrow), 0.15 (colon), 0.19 (lung) and 0.21 (gonads) and for the working population are 0.01 (bone surface and skin), 0.03 (liver, oesophagus and thyroid), 0.04 (breast), 0.06 (remainder), 0.07 (bladder), 0.08 (colon), 0.14 (bone marrow and stomach), 0.16 (lung) and 0.20 (gonads). (author)

  8. Low Sperm Count

    Science.gov (United States)

    ... that the fluid (semen) you ejaculate during an orgasm contains fewer sperm than normal. A low sperm ... ejaculation occurs when semen enters the bladder during orgasm instead of emerging out of the tip of ...

  9. Effect of weight loss by a low-fat diet and a low-carbohydrate diet on peptide YY levels

    OpenAIRE

    Essah, P. A.; Levy, J. R.; Sistrun, S. N.; Kelly, S. M.; Nestler, J. E.

    2010-01-01

    Objective To compare the effects of weight loss by an energy-restricted low-fat diet versus low-carbohydrate diet on serum peptide YY (PYY) levels. Design 8-week prospective study of 30 obese adults (mean age: 42.8 ± 2.0 years, mean BMI 35.5 ± 0.6 kg/m2). Results After 8 weeks, subjects on the low-carbohydrate diet lost substantially more weight than those on the low-fat diet (5.8 kg vs. 0.99 kg, p

  10. Sleep stage classification with low complexity and low bit rate.

    Science.gov (United States)

    Virkkala, Jussi; Värri, Alpo; Hasan, Joel; Himanen, Sari-Leena; Müller, Kiti

    2009-01-01

    Standard sleep stage classification is based on visual analysis of central (usually also frontal and occipital) EEG, two-channel EOG, and submental EMG signals. The process is complex, using multiple electrodes, and is usually based on relatively high (200-500 Hz) sampling rates. Also at least 12 bit analog to digital conversion is recommended (with 16 bit storage) resulting in total bit rate of at least 12.8 kbit/s. This is not a problem for in-house laboratory sleep studies, but in the case of online wireless self-applicable ambulatory sleep studies, lower complexity and lower bit rates are preferred. In this study we further developed earlier single channel facial EMG/EOG/EEG-based automatic sleep stage classification. An algorithm with a simple decision tree separated 30 s epochs into wakefulness, SREM, S1/S2 and SWS using 18-45 Hz beta power and 0.5-6 Hz amplitude. Improvements included low complexity recursive digital filtering. We also evaluated the effects of a reduced sampling rate, reduced number of quantization steps and reduced dynamic range on the sleep data of 132 training and 131 testing subjects. With the studied algorithm, it was possible to reduce the sampling rate to 50 Hz (having a low pass filter at 90 Hz), and the dynamic range to 244 microV, with an 8 bit resolution resulting in a bit rate of 0.4 kbit/s. Facial electrodes and a low bit rate enables the use of smaller devices for sleep stage classification in home environments.

  11. Quality of life in Nepalese patients with low vision and the impact of low vision services

    Directory of Open Access Journals (Sweden)

    Rajendra Gyawali

    2012-10-01

    Conclusions: Low vision patients have poor quality of life as measured with the NEI VFQ-25. Low vision service is associated with improved visual function, better quality of life and high rate of patient satisfaction.

  12. Low Risk Anomalies?

    DEFF Research Database (Denmark)

    Schneider, Paul; Wagner, Christian; Zechner, Josef

    This paper shows theoretically and empirically that beta- and volatility-based low risk anomalies are driven by return skewness. The empirical patterns concisely match the predictions of our model that endogenizes the role of skewness for stock returns through default risk. With increasing downside...... risk, the standard capital asset pricing model (CAPM) increasingly overestimates expected equity returns relative to firms' true (skew-adjusted) market risk. Empirically, the profitability of betting against beta/volatility increases with firms' downside risk, and the risk-adjusted return differential...... of betting against beta/volatility among low skew firms compared to high skew firms is economically large. Our results suggest that the returns to betting against beta or volatility do not necessarily pose asset pricing puzzles but rather that such strategies collect premia that compensate for skew risk...

  13. Low thermal conductivity skutterudites

    Energy Technology Data Exchange (ETDEWEB)

    Fleurial, J P; Caillat, T; Borshchevsky, A

    1997-07-01

    Recent experimental results on semiconductors with the skutterudite crystal structure show that these materials possess attractive transport properties and have a good potential for achieving ZT values substantially larger than for state-of-the-art thermoelectric materials. Both n-type and p-type conductivity samples have been obtained, using several preparation techniques. Associated with a low hole effective mass, very high carrier mobilities, low electrical resistivities and moderate Seebeck coefficients are obtained in p-type skutterudites. For a comparable doping level, the carrier mobilities of n-type samples are about an order of magnitude lower than the values achieved on p-type samples. However, the much larger electron effective masses and Seebeck coefficients on p-type samples. However, the much larger electron effective masses and Seebeck coefficients make n-type skutterudite promising candidates as well. Unfortunately, the thermal conductivities of the binary skutterudites compounds are too large, particularly at low temperatures, to be useful for thermoelectric applications. Several approaches to the reduction of the lattice thermal conductivity in skutterudites are being pursued: heavy doping, formation of solid solutions and alloys, study of novel ternary and filled skutterudite compounds. All those approaches have already resulted in skutterudite compositions with substantially lower thermal conductivity values in these materials. Recently, superior thermoelectric properties in the moderate to high temperature range were achieved for compositions combining alloying and filling of the skutterudite structure. Experimental results and mechanisms responsible for low thermal conductivity in skutterudites are discussed.

  14. Development of Low Parasitic Light Sensitivity and Low Dark Current 2.8 μm Global Shutter Pixel

    Directory of Open Access Journals (Sweden)

    Toshifumi Yokoyama

    2018-01-01

    Full Text Available Abstract: We developed a low parasitic light sensitivity (PLS and low dark current 2.8 μm global shutter pixel. We propose a new inner lens design concept to realize both low PLS and high quantum efficiency (QE. 1/PLS is 7700 and QE is 62% at a wavelength of 530 nm. We also propose a new storage-gate based memory node for low dark current. P-type implants and negative gate biasing are introduced to suppress dark current at the surface of the memory node. This memory node structure shows the world smallest dark current of 9.5 e−/s at 60 °C.

  15. Is a history of work-related low back injury associated with prevalent low back pain and depression in the general population?

    Directory of Open Access Journals (Sweden)

    Cassidy J David

    2008-02-01

    Full Text Available Abstract Background Little is known about the role of prior occupational low back injury in future episodes of low back pain and disability in the general population. We conducted a study to determine if a lifetime history of work-related low back injury is associated with prevalent severity-graded low back pain, depressive symptoms, or both, in the general population. Methods We used data from the Saskatchewan Health and Back Pain Survey – a population-based cross-sectional survey mailed to a random, stratified sample of 2,184 Saskatchewan adults 20 to 69 years of age in 1995. Information on the main independent variable was gathered by asking respondents whether they had ever injured their low back at work. Our outcomes, the 6-month period prevalence of severity-graded low back pain and depressive symptoms during the past week, were measured with valid and reliable questionnaires. The associations between prior work-related low back injury and our outcomes were estimated through multinomial and binary multivariable logistic regression with adjustment for age, gender, and other important covariates. Results Fifty-five percent of the eligible population participated. Of the 1,086 participants who responded to the question about the main independent variable, 38.0% reported a history of work-related low back injury. A history of work-related low back injury was positively associated with low intensity/low disability low back pain (OR, 3.66; 95%CI, 2.48–5.42, with high intensity/low disability low back pain (OR, 4.03; 95%CI, 2.41–6.76, and with high disability low back pain (OR, 6.76; 95%CI, 3.80–12.01. No association was found between a history of work-related low back injury and depression (OR, 0.85; 95%CI, 0.55–1.30. Conclusion Our analysis shows an association between past occupational low back injury and increasing severity of prevalent low back pain, but not depression. These results suggest that past work-related low back injury

  16. Development strategy research of low-carbon tourist city

    Science.gov (United States)

    Dong, Xiaohong

    2017-04-01

    Construction of low-carbon tourist city has become a strategic choice for the development of city construction in our country, becoming the direction and goal of future city development in China. In this paper, the development strategy of low-carbon tourist city is put forward from the aspects of building low-carbon tourism culture, strengthening and perfecting the relevant rules and regulations, establishing and perfecting the decision-making management mechanism of low-carbon tourist city construction, establishing accurate, timely, efficient and comprehensive ecological environment monitoring and supervision network, building economical resource utilization system, strengthening science and technology supporting of low-carbon city construction, establishing low-carbon tourism scenic spot, low-carbon community or low-carbon demonstration area, etc.

  17. Low pressure pain thresholds are associated with, but does not predispose for, low back pain

    DEFF Research Database (Denmark)

    O'Neill, Søren; Kjær, Per; Graven-Nielsen, Thomas

    2011-01-01

    Chronic pain is often associated with hyperalgesia in cross-sectional studies. In the present study, a random cohort of 40-year-old individuals (n = 264) from the general population was assessed for low back pain (LBP) status and pressure pain threshold (PPT), with follow-up assessment 4 and 8......-lasting LBP, those with a low PPT at baseline (lower 10% percentile) had no increased risk of developing LBP (p > 0.05). The findings indicate that PPT decreases as a consequence of long-lasting pain, whereas a low PPT seems not to constitute a separate risk factor for the development of LBP....

  18. Low-Voltage, Low-Power, and Wide-Tuning-Range Ring-VCO for Frequency ΔΣ Modulator

    DEFF Research Database (Denmark)

    Tuan Vu, Cao; Wisland, Dag T.; Lande, Tor Sverre

    A low-voltage, low-power, and wide-tuning-range VCO which converts an analog input voltage to phase information for a frequency ΔΣ modulator is proposed in this paper. The VCO is based on a differential ring oscillator, which is improved with modified symmetric load and a positive feedback...

  19. Low-exposure tritium radiotoxicity in mammals

    International Nuclear Information System (INIS)

    Dobson, R.L.

    1982-01-01

    A special feature of tritium radiation is the very low energy of the beta particles (5.7 keV average, 18 keV maximum). This low energy results in very short particle ranges in tissue, ranges that are less than cell dimensions. Another result of the low energy is that the ionization density along beta-ray tracks (even though the tracks are short) is significantly greater than that associated with secondary electrons from gamma rays. The studies of tritium radiotoxicity reviewed, involving chronic 3 HOH exposures in mammals, demonstrate in both mice and monkeys that biological effects can be measured following remarkably low levels of exposure --- levels in the range of serious practical interest to radiation protection. (Namekawa, K.)

  20. Low-energy Electro-weak Reactions

    International Nuclear Information System (INIS)

    Gazit, Doron

    2012-01-01

    Chiral effective field theory (EFT) provides a systematic and controlled approach to low-energy nuclear physics. Here, we use chiral EFT to calculate low-energy weak Gamow-Teller transitions. We put special emphasis on the role of two-body (2b) weak currents within the nucleus and discuss their applications in predicting physical observables.

  1. Low energy supersymmetry phenomenology

    CERN Document Server

    Baer, H.; Chen, C.H.; Eberl, H.; Feng, J.L.; Fujii, K.; Gunion, John F.; Kamon, T.; Kao, C.; Lopez, J.L.; Majerotto, W.; McIntyre, P.; Munroe, Ray B.; Murayama, H.; Paige, F.; Porod, W.; Sender, J.; Sopczak, A.; Tata, X.; Tsukamoto, T.; White, J.

    1996-01-01

    We summarize the current status and future prospects for low energy (weak scale) supersymmetry. In particular, we evaluate the capabilities of various e^+e^-, p\\bar p and pp colliders to discover evidence for supersymmetric particles. Furthermore, assuming supersymmetry is discovered, we discuss capabilities of future facilities to dis-entangle the anticipated spectrum of super-particles and, via precision measurements, to test mass and coupling parameters for comparison with various theoretical expectations. We comment upon the complementarity of proposed hadron and e^+e^- machines for a comprehensive study of low energy supersymmetry.

  2. Low energy supersymmetry phenomenology

    International Nuclear Information System (INIS)

    Baer, H.; Chen, C.H.; Gunion, J.; Kamon, T.; Lopez, J.L.; Kao, C.

    1995-04-01

    The authors summarize the current status and future prospects for low energy (weak scale) supersymmetry. In particular, they evaluate the capabilities of various e + e - , p bar p and pp colliders to discover evidence for supersymmetric particles. Furthermore, assuming supersymmetry is discovered, they discuss capabilities of future facilities to disentangle the anticipated spectrum of super-particles, and, via precision measurements, to test mass and coupling parameters for comparison with various theoretical expectations. The authors then comment upon the complementarity of proposed hadron and e + e - machines for a comprehensive study of low energy supersymmetry

  3. WORKSHOP: Low temperature devices

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    With extraterrestrial neutrinos (whether from the sun or further afield) continuing to make science news, and with the search for the so far invisible 'dark matter' of the universe a continual preoccupation, physicists from different walks of life (solid state, low temperature, particles, astrophysics) gathered at a workshop on low temperature devices for the detection of neutrinos and dark matter, held from 12-13 March at Ringberg Castle on Lake Tegernsee in the Bavarian Alps, and organized by the Max Planck Institute for Physics and Astrophysics in Munich

  4. WORKSHOP: Low temperature devices

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1987-06-15

    With extraterrestrial neutrinos (whether from the sun or further afield) continuing to make science news, and with the search for the so far invisible 'dark matter' of the universe a continual preoccupation, physicists from different walks of life (solid state, low temperature, particles, astrophysics) gathered at a workshop on low temperature devices for the detection of neutrinos and dark matter, held from 12-13 March at Ringberg Castle on Lake Tegernsee in the Bavarian Alps, and organized by the Max Planck Institute for Physics and Astrophysics in Munich.

  5. Lowe syndrome

    Directory of Open Access Journals (Sweden)

    Loi Mario

    2006-05-01

    Full Text Available Abstract Lowe syndrome (the oculocerebrorenal syndrome of Lowe, OCRL is a multisystem disorder characterised by anomalies affecting the eye, the nervous system and the kidney. It is a uncommon, panethnic, X-linked disease, with estimated prevalence in the general population of approximately 1 in 500,000. Bilateral cataract and severe hypotonia are present at birth. In the subsequent weeks or months, a proximal renal tubulopathy (Fanconi-type becomes evident and the ocular picture may be complicated by glaucoma and cheloids. Psychomotor retardation is evident in childhood, while behavioural problems prevail and renal complications arise in adolescence. The mutation of the gene OCRL1 localized at Xq26.1, coding for the enzyme phosphatidylinositol (4,5 bisphosphate 5 phosphatase, PtdIns (4,5P2, in the trans-Golgi network is responsible for the disease. Both enzymatic and molecular testing are available for confirmation of the diagnosis and for prenatal detection of the disease. The treatment includes: cataract extraction, glaucoma control, physical and speech therapy, use of drugs to address behavioural problems, and correction of the tubular acidosis and the bone disease with the use of bicarbonate, phosphate, potassium and water. Life span rarely exceeds 40 years.

  6. When Power Shapes Interpersonal Behavior: Low Relationship Power Predicts Men’s Aggressive Responses to Low Situational Power

    Science.gov (United States)

    Overall, Nickola C.; Hammond, Matthew D.; McNulty, James K.; Finkel, Eli J.

    2016-01-01

    When does power in intimate relationships shape important interpersonal behaviors, such as psychological aggression? Five studies tested whether possessing low relationship power was associated with aggressive responses, but (1) only within power-relevant relationship interactions when situational power was low, and (2) only by men because masculinity (but not femininity) involves the possession and demonstration of power. In Studies 1 and 2, men lower in relationship power exhibited greater aggressive communication during couples’ observed conflict discussions, but only when they experienced low situational power because they were unable to influence their partner. In Study 3, men lower in relationship power reported greater daily aggressive responses toward their partner, but only on days when they experienced low situational power because they were either (a) unable to influence their partner or (b) dependent on their partner for support. In Study 4, men who possessed lower relationship power exhibited greater aggressive responses during couples’ support-relevant discussions, but only when they had low situational power because they needed high levels of support. Study 5 provided evidence for the theoretical mechanism underlying men’s aggressive responses to low relationship power. Men who possessed lower relationship power felt less manly on days they faced low situational power because their partner was unwilling to change to resolve relationship problems, which in turn predicted greater aggressive responses to their partner. These results demonstrate that fully understanding when and why power is associated with interpersonal behavior requires differentiating between relationship and situational power. PMID:27442766

  7. NASA's Pursuit of Low-Noise Propulsion for Low-Boom Commercial Supersonic Vehicles

    Science.gov (United States)

    Bridges, James; Brown, Clifford A.; Seidel, Jonathan A.

    2018-01-01

    Since 2006, when the Fundamental Aeronautics Program was instituted within NASA's Aeronautics Mission Directorate, there has been a Project looking at the technical barriers to commercial supersonic flight. Among the barriers is the noise produced by aircraft during landing and takeoff. Over the years that followed, research was carried out at NASA aeronautics research centers, often in collaboration with academia and industry, addressing the problem. In 2013, a high-level milestone was established, described as a Technical Challenge, with the objective of demonstrating the feasibility of a low-boom supersonic airliner that could meet current airport noise regulations. The Technical Challenge was formally called "Low Noise Propulsion for Low Boom Aircraft", and was completed in late 2016. This paper reports the technical findings from this Technical Challenge, reaching back almost 10 years to review the technologies and tools that were developed along the way. It also discusses the final aircraft configuration and propulsion systems required for a supersonic civilian aircraft to meet noise regulations using the technologies available today. Finally, the paper documents the model-scale tests that validated the acoustic performance of the study aircraft.

  8. Low-Power Public Key Cryptography

    Energy Technology Data Exchange (ETDEWEB)

    BEAVER,CHERYL L.; DRAELOS,TIMOTHY J.; HAMILTON,VICTORIA A.; SCHROEPPEL,RICHARD C.; GONZALES,RITA A.; MILLER,RUSSELL D.; THOMAS,EDWARD V.

    2000-11-01

    This report presents research on public key, digital signature algorithms for cryptographic authentication in low-powered, low-computation environments. We assessed algorithms for suitability based on their signature size, and computation and storage requirements. We evaluated a variety of general purpose and special purpose computing platforms to address issues such as memory, voltage requirements, and special functionality for low-powered applications. In addition, we examined custom design platforms. We found that a custom design offers the most flexibility and can be optimized for specific algorithms. Furthermore, the entire platform can exist on a single Application Specific Integrated Circuit (ASIC) or can be integrated with commercially available components to produce the desired computing platform.

  9. SigWx-Low

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The low-level graphics product is a forecast of aviation weather hazards, primarily intended to be used as a guidance product for briefing the VFR pilot. The...

  10. Low-charge-state RFQ injector

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, K.W.; Kim, J.W.

    1995-08-01

    Preliminary design work was done for a short, normally-conducting RFQ entrance section for a low-charge-state linac. Early results indicate that a low- frequency (12 MHz) RFQ, operated on a high-voltage platform, and injected with a pre-bunched beam, can provide ATLAS quality beams of ions of charge-to-mass ratio less than 1/132.

  11. In Situ Irradiation and Measurement of Triple Junction Solar Cells at Low Intensity, Low Temperature (LILT) Conditions

    Science.gov (United States)

    Harris, R.D.; Imaizumi, M.; Walters, R.J.; Lorentzen, J.R.; Messenger, S.R.; Tischler, J.G.; Ohshima, T.; Sato, S.; Sharps, P.R.; Fatemi, N.S.

    2008-01-01

    The performance of triple junction InGaP/(In)GaAs/Ge space solar cells was studied following high energy electron irradiation at low temperature. Cell characterization was carried out in situ at the irradiation temperature while using low intensity illumination, and, as such, these conditions reflect those found for deep space, solar powered missions that are far from the sun. Cell characterization consisted of I-V measurements and quantum efficiency measurements. The low temperature irradiations caused substantial degradation that differs in some ways from that seen after room temperature irradiations. The short circuit current degrades more at low temperature while the open circuit voltage degrades more at room temperature. A room temperature anneal after the low temperature irradiation produced a substantial recovery in the degradation. Following irradiation at both temperatures and an extended room temperature anneal, quantum efficiency measurement suggests that the bulk of the remaining damage is in the (In)GaAs sub-cell

  12. Voluntary low-force contraction elicits prolonged low-frequency fatigue and changes in surface electromyography and mechanomyography

    DEFF Research Database (Denmark)

    Blangsted, Anne Katrine; Sjøgaard, Gisela; Madeleine, Pascal

    2005-01-01

    Controversies exist regarding objective documentation of fatigue development with low-force contractions. We hypothesized that non-exhaustive, low-force muscle contraction may induce prolonged low-frequency fatigue (LFF) that in the subsequent recovery period is detectable by electromyography (EMG......) and in particular mechanomyography (MMG) during low-force rather than high-force test contractions. Seven subjects performed static wrist extension at 10% maximal voluntary contraction (MVC) for 10 min (10%MVC10 min). Wrist force response to electrical stimulation of extensor carpi radialis muscle (ECR) quantified...... LFF. EMG and MMG were recorded from ECR during static test contractions at 5% and 80% MVC. Electrical stimulation, MVC, and test contractions were performed before 10%MVC10 min and at 10, 30, 90 and 150 min recovery. In spite of no changes in MVC, LFF persisted up to 150 min recovery but did...

  13. Extremely low temperature properties of epoxy GFRP

    International Nuclear Information System (INIS)

    Kadotani, Kenzo; Nagai, Matao; Aki, Fumitake.

    1983-01-01

    The examination of fiber-reinforced plastics, that is, plastics such as epoxy, polyester and polyimide reinforced with high strength fibers such as glass, carbon, boron and steel, for extremely low temperature use began from the fuel tanks of rockets. Therafter, the trial manufacture of superconducting generators and extremely low temperature transformers and the manufacture of superconducting magnets for nuclear fusion experimental setups became active, and high performance FRPs have been adopted, of which the extremely low temperature properties have been sufficiently grasped. Recently, the cryostats made of FRPs have been developed, fully utilizing such features of FRPs as high strength, high rigidity, non-magnetic material, insulation, low heat conductivity, light weight and the freedom of molding. In this paper, the mechanical properties at extremely low temperature of the plastic composite materials used as insulators and structural materials for extremely low temperature superconducting equipment is outlined, and in particular, glass fiber-reinforced epoxy laminates are described somewhat in detail. The fracture strain of GFRP at extremely low temperature is about 1.3 times as large as that at room temperature, but at extremely low temperature, clear cracking occurred at 40% of the fracture strain. The linear thermal contraction of GFRP showed remarkable anisotropy. (Kako, I.)

  14. Ameliorative effects of low dose/low dose-rate irradiation on reactive oxygen species-related diseases model mice

    International Nuclear Information System (INIS)

    Nomura, Takaharu

    2008-01-01

    Living organisms have developed complex biological system which protects themselves against environmental radiation, and irradiation with proper dose, dose-rate and irradiation time can stimulate their biological responses against oxidative stress evoked by the irradiation. Because reactive oxygen species are involved in various human diseases, non-toxic low dose/low dose-rate radiation can be utilized for the amelioration of such diseases. In this study, we used mouse experimental models for fatty liver, nephritis, diabetes, and ageing to elucidate the ameliorative effect of low dose/low dose-rate radiation in relation to endogenous antioxidant activity. Single irradiation at 0.5 Gy ameliorates carbon tetrachloride-induced fatty liver. The irradiation increases hepatic anti-oxidative system involving glutathione and glutathione peroxidase, suggesting that endogenous radical scavenger is essential for the ameliorative effect of low dose radiation on carbon tetrachloride-induced fatty liver. Single irradiation at 0.5 Gy ameliorates ferric nitrilotriacetate-induced nephritis. The irradiation increases catalase and decreases superoxide dismutase in kidney. The result suggests that low dose radiation reduced generation of hydroxide radical generation by reducing cellular hydroperoxide level. Single irradiation at 0.5 Gy at 12 week of age ameliorates incidence of type I diabetes in non-obese diabetic (NOD) mice through the suppression of inflammatory activity of splenocytes, and resultant apoptosis of β-cells in pancreas. The irradiation activities of superoxide dismutase and catalase, which coordinately diminish intracellular reactive oxygen species. Continuous irradiation at 0.70 mGy/hr from 10 week of age elongates life span, and suppresses alopecia in type II diabetesmice. The irradiation improved glucose clearance without affecting insulin-resistance, and increased pancreatic catalase activity. The results suggest that continuous low dose-rate irradiation protect

  15. Low-input, low-cost IPM program helps manage potato psyllid

    Directory of Open Access Journals (Sweden)

    Sean M. Prager

    2016-04-01

    Full Text Available Potato psyllid is a pest of solanaceous plants throughout much of the western United States, including California, where it has increased and is now overwintering. The psyllid affects its plant hosts from direct feeding and by transmitting a plant pathogenic bacterium, Lso. Millions of dollars of damages have occurred in the U.S. potato industry, and a large acreage of crops is susceptible in California. Control is complicated because different crops have different pest complexes and susceptibilities to Lso; currently most growers use multiple pesticide applications, including broad-spectrum insecticides. Results of our field trials at South Coast Research and Extension Center indicate that the use of broad-spectrum insecticides actually increases psyllid numbers in both peppers and potatoes. We have developed a low-input IPM program, which in field trials produced encouraging results in peppers, potatoes and tomatoes compared to broad-spectrum insecticides. Economic analysis showed the low-input IPM approach was more cost effective than a standard insecticide program in tomatoes.

  16. Mammography-oncogenecity at low doses

    International Nuclear Information System (INIS)

    Heyes, G J; Mill, A J; Charles, M W

    2009-01-01

    Controversy exists regarding the biological effectiveness of low energy x-rays used for mammography breast screening. Recent radiobiology studies have provided compelling evidence that these low energy x-rays may be 4.42 ± 2.02 times more effective in causing mutational damage than higher energy x-rays. These data include a study involving in vitro irradiation of a human cell line using a mammography x-ray source and a high energy source which matches the spectrum of radiation observed in survivors from the Hiroshima atomic bomb. Current radiation risk estimates rely heavily on data from the atomic bomb survivors, and a direct comparison between the diagnostic energies used in the UK breast screening programme and those used for risk estimates can now be made. Evidence highlighting the increase in relative biological effectiveness (RBE) of mammography x-rays to a range of x-ray energies implies that the risks of radiation-induced breast cancers for mammography x-rays are potentially underestimated by a factor of four. A pooled analysis of three measurements gives a maximal RBE (for malignant transformation of human cells in vitro) of 4.02 ± 0.72 for 29 kVp (peak accelerating voltage) x-rays compared to high energy electrons and higher energy x-rays. For the majority of women in the UK NHS breast screening programme, it is shown that the benefit safely exceeds the risk of possible cancer induction even when this higher biological effectiveness factor is applied. The risk/benefit analysis, however, implies the need for caution for women screened under the age of 50, and particularly for those with a family history (and therefore a likely genetic susceptibility) of breast cancer. In vitro radiobiological data are generally acquired at high doses, and there are different extrapolation mechanisms to the low doses seen clinically. Recent low dose in vitro data have indicated a potential suppressive effect at very low dose rates and doses. Whilst mammography is a low

  17. Energy generation in convective shells of low mass, low metallicity stars

    International Nuclear Information System (INIS)

    Bazan, G.

    1989-01-01

    We report on the non-negligible energy generation from the 13 C neutron source and neutron capture reactions in low mass, low metallicity AGB stars. About 10 4 L circle-dot are generated within the thermal pulse convective shell by the combination of the 13 C(α, n) 16 O rate and the sum of the Y(Z,A)(n,γ)Y(Z,A + 1) reactions and beta decays. The inclusion of this energy source in an AGB thermal pulse evolution is shown to alter the evolution of the convective shell boundaries, and, hence, how the 13 C is ingested into the convective shell. Also, the duration of the pulse itself is reduced by the additional energy input. The nucleosynthetic consequences are discussed for these evolutionary changes. 17 refs., 5 figs

  18. THE KINEMATICS OF THE NEBULAR SHELLS AROUND LOW MASS PROGENITORS OF PNe WITH LOW METALLICITY

    Energy Technology Data Exchange (ETDEWEB)

    Pereyra, Margarita; López, José Alberto; Richer, Michael G., E-mail: mally@astrosen.unam.mx, E-mail: jal@astrosen.unam.mx, E-mail: richer@astrosen.unam.mx [Instituto de Astronomía, Universidad Nacional Autónoma de México, Apartado Postal 106, C.P. 22800 Ensenada, BC, México (Mexico)

    2016-03-15

    We analyze the internal kinematics of 26 planetary nebulae (PNe) with low metallicity that appear to derive from progenitor stars of the lowest masses, including the halo PN population. Based upon spatially resolved, long-slit, echelle spectroscopy drawn from the San Pedro Mártir Kinematic Catalog of PNe, we characterize the kinematics of these PNe measuring their global expansion velocities based upon the largest sample used to date for this purpose. We find kinematics that follow the trends observed and predicted in other studies, but also find that most of the PNe studied here tend to have expansion velocities less than 20 km s{sup −1} in all of the emission lines considered. The low expansion velocities that we observe in this sample of low metallicity PNe with low mass progenitors are most likely a consequence of a weak central star (CS) wind driving the kinematics of the nebular shell. This study complements previous results that link the expansion velocities of the PN shells with the characteristics of the CS.

  19. An ultra low noise AC beam transformer for deceleration and diagnostics of low intensity beams

    CERN Document Server

    González, C

    1999-01-01

    The design of a broad band ultra-low noise ferrite loaded AC beam transformer is presented. It is designed for use in the CERN Antiproton Decelerator (AD), where beams of a few 107 charges must be decelerated from 3.5 GeV/c to 100 MeV/c. It is used in the RF beam-phase loop, and for intensity and bunch shape measurements during deceleration. When the beam is debunched for cooling on magnetic flat tops, the pick-up is used for measurements of intensity and momentum distribution by means of longitudinal Schottky scans. When used as Schottky pick-up, the signal to noise ratio should be better by about 40 dB than the existing stripline based longitudinal Schottky pick-up. The integrated design of pick-up and associated low-noise amplifier is presented. The achieved noise performance of a few from 1 to 3 MHz is obtained by attaching a low-noise, high-impedance silicon JFET (junction field effect transistor) amplifier to a high-Q resonant ferrite loaded cavity, and then eliminating the resonant response by low-nois...

  20. Have You Switched to a Low-Carbon Diet? The Ultimate Value of Low-Carbon Consumerism

    Directory of Open Access Journals (Sweden)

    Yu-Ling Lin

    2014-04-01

    Full Text Available Since the 1990s many governments around the world have been encouraging their people to participate in green or low carbon living. With the background of rising consumer awareness in environmental protection, green consumption, and green marketing are receiving growing attention from consumers and enterprises. Therefore, the purpose of this paper is to identify the goals and values of 60 Taiwanese consumers in a low-carbon diet. This study uses the theory of Mean-end chain as basis, applying the “Soft-laddering” of “Laddering” to understand the perceived value of low carbon food in depth interviews. The results revealed that the attributes of users care for green living in the, order of, Less meat more vegetables, Seasonal food, Local food, Food with minimal artificial processing, Energy-saving preparation and Carbon footprint. After classifying by content analysis, we draw the Hierarchical value map (HVM to explore that consumer’s pursuit of the final value and benefits by adopting a low-carbon diet relate to healthy living.

  1. How low is low? Low self-esteem as an indicator of internalizing psychopathology in adolescence.

    Science.gov (United States)

    Isomaa, Rasmus; Väänänen, Juha-Matti; Fröjd, Sari; Kaltiala-Heino, Riittakerttu; Marttunen, Mauri

    2013-08-01

    Schools are among the most important setting for preventive interventions among adolescents. There are evidence-based intervention programs for adolescents at risk for and with early signs of mental health problems but one demanding task is to detect the ones who are in need of an intervention. The aim of the present study was to analyze associations between self-esteem, depressive symptoms, and social anxiety in order to determine clinically relevant cut-points for male and female adolescents' self-esteem as measured with the Rosenberg Self-Esteem Scale (RSES). The participants of the present prospective study, started in 2002-2003, were 2070 adolescents aged 15 years (1,167 girls and 903 boys) at two study sites in Finland who participated at both baseline and 2-year follow-up. Self-esteem was related to depressive symptoms and social anxiety, and the RSES was able to discriminate between cases of depression and social phobia. The present study suggests a cutoff of 25 points to classify low self-esteem in both girls and boys. Low self-esteem may function as an indicator of various forms of internalizing psychopathology. The RSES is worth further examination as a potential screening tool for adolescents in risk of psychopathology.

  2. Low magnesium level

    Science.gov (United States)

    Low magnesium level is a condition in which the amount of magnesium in the blood is lower than normal. The medical ... that convert or use energy ( metabolism ). When the level of magnesium in the body drops below normal, ...

  3. Low-set ears and pinna abnormalities

    Science.gov (United States)

    Low-set ears; Microtia; "Lop" ear; Pinna abnormalities; Genetic defect - pinna; Congenital defect - pinna ... conditions: Abnormal folds or location of the pinna Low-set ears No opening to the ear canal ...

  4. Flow reversal at low voltage and low frequency in a microfabricated ac electrokinetic pump

    DEFF Research Database (Denmark)

    Gregersen, Misha Marie; Olesen, Laurits Højgaard; Brask, Anders

    2007-01-01

    measured in a regime, where both the applied voltage and the frequency are low, Vrms1.5 V and f20 kHz, compared to previously investigated parameter ranges. The impedance spectrum has been thoroughly measured and analyzed in terms of an equivalent circuit diagram to rule out trivial circuit explanations......Microfluidic chips have been fabricated in Pyrex glass to study electrokinetic pumping generated by a low-voltage ac bias applied to an in-channel asymmetric metallic electrode array. A measurement procedure has been established and followed carefully resulting in a high degree of reproducibility...... of the measurements over several days. A large coverage fraction of the electrode array in the microfluidic channels has led to an increased sensitivity allowing for pumping measurements at low bias voltages. Depending on the ionic concentration a hitherto unobserved reversal of the pumping direction has been...

  5. Investigating Low-Carbon City: Empirical Study of Shanghai

    Directory of Open Access Journals (Sweden)

    Xuan Yang

    2018-04-01

    Full Text Available A low-carbon economy is an inevitable choice for achieving economic and ecological sustainable development. It is of significant importance to analyze a city’s low-carbon economy development level scientifically and reasonably. In order to achieve this goal, we propose an urban low-carbon economic development level evaluation model based on the matter-element extension method. First, we select some indicators from the existing indicator system based on past research and experience. Then, a matter-element model is established on the basis of weight to evaluate the level of a city’s low-carbon, the critical value of each index is determined through the classical domain and the section domain, calculating the correlation degree of a single index and a comprehensive index. Finally, we analyze the low-carbon economy development status and future development trends according to the analysis results. In this study, we select Shanghai as an empirical study—the results show that Shanghai is a city with a low-carbon level and there is a trend of further improvement in Shanghai’s low-carbon economy. But its low carbon construction and low carbon technology investment are relatively low. In summary, this method can provide another angle for evaluating a city’s low-carbon economy.

  6. Production of low-affinity penicillin-binding protein by low- and high-resistance groups of methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Murakami, K; Nomura, K; Doi, M; Yoshida, T

    1987-01-01

    Methicillin- and cephem-resistant Staphylococcus aureus (137 strains) for which the cefazolin MICs are at least 25 micrograms/ml could be classified into low-resistance (83% of strains) and high-resistance (the remaining 17%) groups by the MIC of flomoxef (6315-S), a 1-oxacephalosporin. The MICs were less than 6.3 micrograms/ml and more than 12.5 micrograms/ml in the low- and high-resistance groups, respectively. All strains produced penicillin-binding protein 2' (PBP 2'), which has been associated with methicillin resistance and which has very low affinity for beta-lactam antibiotics. Production of PBP 2' was regulated differently in low- and high-resistance strains. With penicillinase-producing strains of the low-resistance group, cefazolin, cefamandole, and cefmetazole induced PBP 2' production about 5-fold, while flomoxef induced production 2.4-fold or less. In contrast, penicillinase-negative variants of low-resistance strains produced PBP 2' constitutively in large amounts and induction did not occur. With high-resistance strains, flomoxef induced PBP 2' to an extent similar to that of cefazolin in both penicillinase-producing and -negative strains, except for one strain in which the induction did not occur. The amount of PBP 2' induced by beta-lactam antibiotics in penicillinase-producing strains of the low-resistance group correlated well with resistance to each antibiotic. Large amounts of PBP 2' in penicillinase-negative variants of the low-resistance group did not raise the MICs of beta-lactam compounds, although these strains were more resistant when challenged with flomoxef for 2 h. Different regulation of PBP 2' production was demonstrated in the high- and low-resistance groups, and factor(s) other than PBP 2' were suggested to be involved in the methicillin resistance of high-resistance strains. Images PMID:3499861

  7. Comparison of cryogenic low-pass filters

    Science.gov (United States)

    Thalmann, M.; Pernau, H.-F.; Strunk, C.; Scheer, E.; Pietsch, T.

    2017-11-01

    Low-temperature electronic transport measurements with high energy resolution require both effective low-pass filtering of high-frequency input noise and an optimized thermalization of the electronic system of the experiment. In recent years, elaborate filter designs have been developed for cryogenic low-level measurements, driven by the growing interest in fundamental quantum-physical phenomena at energy scales corresponding to temperatures in the few millikelvin regime. However, a single filter concept is often insufficient to thermalize the electronic system to the cryogenic bath and eliminate spurious high frequency noise. Moreover, the available concepts often provide inadequate filtering to operate at temperatures below 10 mK, which are routinely available now in dilution cryogenic systems. Herein we provide a comprehensive analysis of commonly used filter types, introduce a novel compact filter type based on ferrite compounds optimized for the frequency range above 20 GHz, and develop an improved filtering scheme providing adaptable broad-band low-pass characteristic for cryogenic low-level and quantum measurement applications at temperatures down to few millikelvin.

  8. Comparison of cryogenic low-pass filters.

    Science.gov (United States)

    Thalmann, M; Pernau, H-F; Strunk, C; Scheer, E; Pietsch, T

    2017-11-01

    Low-temperature electronic transport measurements with high energy resolution require both effective low-pass filtering of high-frequency input noise and an optimized thermalization of the electronic system of the experiment. In recent years, elaborate filter designs have been developed for cryogenic low-level measurements, driven by the growing interest in fundamental quantum-physical phenomena at energy scales corresponding to temperatures in the few millikelvin regime. However, a single filter concept is often insufficient to thermalize the electronic system to the cryogenic bath and eliminate spurious high frequency noise. Moreover, the available concepts often provide inadequate filtering to operate at temperatures below 10 mK, which are routinely available now in dilution cryogenic systems. Herein we provide a comprehensive analysis of commonly used filter types, introduce a novel compact filter type based on ferrite compounds optimized for the frequency range above 20 GHz, and develop an improved filtering scheme providing adaptable broad-band low-pass characteristic for cryogenic low-level and quantum measurement applications at temperatures down to few millikelvin.

  9. A low-carbohydrate as compared with a low-fat diet in severe obesity.

    Science.gov (United States)

    Samaha, Frederick F; Iqbal, Nayyar; Seshadri, Prakash; Chicano, Kathryn L; Daily, Denise A; McGrory, Joyce; Williams, Terrence; Williams, Monica; Gracely, Edward J; Stern, Linda

    2003-05-22

    The effects of a carbohydrate-restricted diet on weight loss and risk factors for atherosclerosis have been incompletely assessed. We randomly assigned 132 severely obese subjects (including 77 blacks and 23 women) with a mean body-mass index of 43 and a high prevalence of diabetes (39 percent) or the metabolic syndrome (43 percent) to a carbohydrate-restricted (low-carbohydrate) diet or a calorie- and fat-restricted (low-fat) diet. Seventy-nine subjects completed the six-month study. An analysis including all subjects, with the last observation carried forward for those who dropped out, showed that subjects on the low-carbohydrate diet lost more weight than those on the low-fat diet (mean [+/-SD], -5.8+/-8.6 kg vs. -1.9+/-4.2 kg; P=0.002) and had greater decreases in triglyceride levels (mean, -20+/-43 percent vs. -4+/-31 percent; P=0.001), irrespective of the use or nonuse of hypoglycemic or lipid-lowering medications. Insulin sensitivity, measured only in subjects without diabetes, also improved more among subjects on the low-carbohydrate diet (6+/-9 percent vs. -3+/-8 percent, P=0.01). The amount of weight lost (Plow-carbohydrate diet (P=0.01) were independent predictors of improvement in triglyceride levels and insulin sensitivity. Severely obese subjects with a high prevalence of diabetes or the metabolic syndrome lost more weight during six months on a carbohydrate-restricted diet than on a calorie- and fat-restricted diet, with a relative improvement in insulin sensitivity and triglyceride levels, even after adjustment for the amount of weight lost. This finding should be interpreted with caution, given the small magnitude of overall and between-group differences in weight loss in these markedly obese subjects and the short duration of the study. Future studies evaluating long-term cardiovascular outcomes are needed before a carbohydrate-restricted diet can be endorsed. Copyright 2003 Massachusetts Medical Society

  10. Low-Salt Intake during Mating or Gestation in Rats Is Associated with Low Birth and Survival Rates of Babies

    Directory of Open Access Journals (Sweden)

    Ranna Chou

    2014-01-01

    Full Text Available We investigated the influence of maternal salt restriction during mating or gestation on birth rate and offspring growth in Dahl salt-sensitive rats (DS. DS were divided into 5 groups: DS fed a low-salt (0.3% NaCl, w/w (DS-low or high-salt (4% NaCl, w/w diet (DS-high during mating and DS-high or DS-low during gestation, and DS fed regular chow (0.75% NaCl, w/w (DS-regular throughout mating and gestation. During the unspecified periods, the rats were given regular chow. DS-low during mating delivered fewer infants than high-salt mothers (P<0.05. The birth rate on regular chow was 87%. Six out of 11 DS-low rats during pregnancy produced pups while the rats fed a high-salt diet all delivered pups (P<0.025. The pup survival rate was 67% for high-salt mothers during mating and 54% for mothers on a low-salt diet. The pup survival rate was 95% for mothers on a high-salt diet during pregnancy and 64% for mothers on a low-salt diet (P<0.0001. Seven out of 8 DS-regular rats during mating delivered 59 neonates. However, 66% of the neonates survived. A low-salt diet during mating or pregnancy lowers birth rate and the neonates from low-salt mothers during pregnancy were more likely to die than those from high-salt mothers.

  11. Low-salt diet

    Science.gov (United States)

    Low-sodium diet; Salt restriction ... control many functions. Too much sodium in your diet can be bad for you. For most people, ... you limit salt. Try to eat a balanced diet. Buy fresh vegetables and fruits whenever possible. They ...

  12. IRMM low level underground laboratory in HADES

    Energy Technology Data Exchange (ETDEWEB)

    Mouchel, D [CEC-JRC, Inst. for Reference Materials and Measurements (IRMM), Geel (Belgium); Wordel, R [CEC-JRC, Inst. for Reference Materials and Measurements (IRMM), Geel (Belgium)

    1997-03-01

    The operation of low background HPGe detectors at a depth of 225 m, reduced the background by two orders of magnitude; a large amount of the remaining background is still attributable to the cosmic rays. The selection of radiopure materials, the characterization of reference matrices and the measurements of low radioactivities in environmental samples are performed. Coupling the low level spectrometry with additional techniques, e.g. neutron activation, will allow to measure extremely low radioactivities. (orig.)

  13. Basics of Low-temperature Refrigeration

    CERN Document Server

    Alekseev, A.

    2014-07-17

    This chapter gives an overview of the principles of low temperature refrigeration and the thermodynamics behind it. Basic cryogenic processes - Joule-Thomoson process, Brayton process as well as Claude process - are described and compared. A typical helium laboratory refrigerator based on Claude process is used as a typical example of a low-temperature refrigeration system. A description of the hardware components for helium liquefaction is an important part of this paper, because the design of the main hardware components (compressors, turbines, heat exchangers, pumps, adsorbers, etc.) provides the input for cost calculation, as well as enables to estimate the reliability of the plant and the maintenance expenses. All these numbers are necessary to calculate the economics of a low temperature application.

  14. Basics of Low-temperature Refrigeration

    Energy Technology Data Exchange (ETDEWEB)

    Alekseev, A [Linde AG, Munich (Germany)

    2014-07-01

    This chapter gives an overview of the principles of low temperature refrigeration and the thermodynamics behind it. Basic cryogenic processes - Joule-Thomoson process, Brayton process as well as Claude process - are described and compared. A typical helium laboratory refrigerator based on Claude process is used as a typical example of a low-temperature refrigeration system. A description of the hardware components for helium liquefaction is an important part of this paper, because the design of the main hardware components (compressors, turbines, heat exchangers, pumps, adsorbers, etc.) provides the input for cost calculation, as well as enables to estimate the reliability of the plant and the maintenance expenses. All these numbers are necessary to calculate the economics of a low temperature application.

  15. Post-dryout heat transfer and entrained droplet sizes at low pressure and low flow conditions

    International Nuclear Information System (INIS)

    Jeong, H.Y.; No, H.C.

    1997-01-01

    The entrainment mechanisms and the entrained droplet sizes with relation to the flow regimes are investigated. Through the analysis of many experimental post-dryout data, it is shown that the most probable flow regime near dryout or quench front is not annular flow but churn-turbulent flow when the mass flux is low. A correlation describing the initial droplet size just after the CHF position at low mass flux is suggested through regression analysis. The history-dependent post-dryout model of Varone and Rohsenow replaced by the Webb-Chen model for wall-vapor heat transfer is used as a reference model in the analysis. In the post-dryout region at low pressure and low flow, it is found that the suggested one-dimensional mechanistic model is not applicable when the vapor superficial velocity is very low. This is explained by the change of main entrainment mechanism with the change of flow regime. In bubbly or slug flow a number of tiny droplets generated from bubble burst become important in the heat transfer after dryout. Therefore, the suggested correlation is valid only in the churn-turbulent flow regime (j g * = 0.5∼4.5). It is also suggested that the droplet size generated from the churn-turbulent surface is dependent not only on the pressure but also on the vapor velocity. It turns out that the present model can predict the measured cladding and vapor temperatures within 20% and 25%, respectively

  16. Searching for chaos on low frequency

    OpenAIRE

    Nicolas Wesner

    2004-01-01

    A new method for detecting low dimensional chaos in small sample sets is presented. The method is applied to financial data on low frequency (annual and monthly) for which few observations are available.

  17. Lowe syndrome: case report

    Directory of Open Access Journals (Sweden)

    Eva Bahor

    2018-03-01

    Full Text Available Lowe syndrome is a rare X-linked multisystemic disorder, caused by mutation of the OCRL gene which encodes OCRL-1 protein. The disease is characterized by the triad of congenital cataracts, intellectual disability, and Fanconi-like proximal renal tubular dysfunction. Lifespan is short due to end-stage renal disease and other earlier complications and it rarely exceeds 40 years. The treatment is symptomatic, aimed at improving the clinical evolution of the patients and postpone the onset of terminal renal disease. The paper describes a case of a boy with Lowe syndrome with a novel genetic mutation.

  18. The semi-empirical low-level background statistics

    International Nuclear Information System (INIS)

    Tran Manh Toan; Nguyen Trieu Tu

    1992-01-01

    A semi-empirical low-level background statistics was proposed. The one can be applied to evaluated the sensitivity of low background systems, and to analyse the statistical error, the 'Rejection' and 'Accordance' criteria for processing of low-level experimental data. (author). 5 refs, 1 figs

  19. Is low-dose amitriptyline effective in the management of chronic low back pain? Study protocol for a randomised controlled trial.

    Science.gov (United States)

    Urquhart, Donna M; Wluka, Anita E; Sim, Malcolm R; van Tulder, Maurits; Forbes, Andrew; Gibson, Stephen J; Arnold, Carolyn; Fong, Chris; Anthony, Shane N; Cicuttini, Flavia M

    2016-10-22

    Low back pain is a major clinical and public health problem, with limited evidence-based treatments. Low-dose antidepressants are commonly used to treat pain in chronic low back pain. However, their efficacy is unproven. The aim of this pragmatic, double-blind, randomised, placebo-controlled trial is to determine whether low-dose amitriptyline (an antidepressant) is more effective than placebo in reducing pain in individuals with chronic low back pain. One hundred and fifty individuals with chronic low back pain will be recruited through hospital and private medical and allied health clinics, advertising in local media and posting of flyers in community locations. They will be randomly allocated to receive either low-dose amitriptyline (25 mg) or an active placebo (benztropine mesylate, 1 mg) for 6 months. The primary outcome measure of pain intensity will be assessed at baseline, 3 and 6 months using validated questionnaires. Secondary measures of self-reported low back disability, work absence and hindrance in the performance of paid/unpaid work will also be examined. Intention-to-treat analyses will be performed. This pragmatic, double-blind, randomised, placebo-controlled trial will provide evidence regarding the effectiveness of low-dose antidepressants compared with placebo in reducing pain, disability, work absenteeism and hindrance in work performance in individuals with chronic low back pain. This trial has major public health and clinical importance as it has the potential to provide an effective approach to the management of chronic low back pain. Australian New Zealand Clinical Trials Registry: ACTRN12612000131853 ; registered on 30 January 2012.

  20. Optical properties of low-dimensional materials

    CERN Document Server

    Ogawa, T

    1998-01-01

    This book surveys recent theoretical and experimental studies of optical properties of low-dimensional materials. As an extended version of Optical Properties of Low-Dimensional Materials (Volume 1, published in 1995 by World Scientific), Volume 2 covers a wide range of interesting low-dimensional materials including both inorganic and organic systems, such as disordered polymers, deformable molecular crystals, dilute magnetic semiconductors, SiGe/Si short-period superlattices, GaAs quantum wires, semiconductor microcavities, and photonic crystals. There are excellent review articles by promis