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Sample records for large herd size

  1. Why herd size matters - mitigating the effects of livestock crashes.

    Directory of Open Access Journals (Sweden)

    Marius Warg Næss

    Full Text Available Analysing the effect of pastoral risk management strategies provides insights into a system of subsistence that have persevered in marginal areas for hundreds to thousands of years and may shed light into the future of around 200 million households in the face of climate change. This study investigated the efficiency of herd accumulation as a buffer strategy by analysing changes in livestock holdings during an environmental crisis in the Saami reindeer husbandry in Norway. We found a positive relationship between: (1 pre- and post-collapse herd size; and (2 pre-collapse herd size and the number of animals lost during the collapse, indicating that herd accumulation is an effective but costly strategy. Policies that fail to incorporate the risk-beneficial aspect of herd accumulation will have a limited effect and may indeed fail entirely. In the context of climate change, official policies that incorporate pastoral risk management strategies may be the only solution for ensuring their continued existence.

  2. Impact if hyperprolific line of litter size in multiplication herd

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    Zdeněk Tvrdoň

    2009-01-01

    Full Text Available The hyperprolific line is considered to be maximally effective in pursuit of progress in sow’s reproduction. Hyperprolific line efficiency is commonly evaluated in regard of breeding herd progress. We decided to study how effective it is with respect to increasing of litter size in multiplication herd. Our study is specific by using the data from practice, concretely it is based on the information about the ancestor of sows in multiplication herd. The ancestors could be the member either hyperprolific line or normal line. The information about performances of sows breed in multiplication herd was known. The mixed linear models in SAS for Windows 9.1.2. were conducted to statistical analysis. Our results indicated that no significant effect on litter size was achieved by selection criteria used in the hyperprolific line creation. In studied population no differences between TNB, NBA or NW were found on the 1st as well as on the 1st–5th litters. As we have mentioned above, the study is specific by using the data from practice. Therefore the studied population size is limited. It is necessary to take into consideration when the results are applied. Nevertheless, the results shown that other studies with larger population should be done to reevaluate the selection criteria.

  3. Modelling Pasture-based Automatic Milking System Herds: The Impact of Large Herd on Milk Yield and Economics

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    M. R. Islam

    2015-07-01

    Full Text Available The aim of this modelling study was to investigate the effect of large herd size (and land areas on walking distances and milking interval (MI, and their impact on milk yield and economic penalties when 50% of the total diets were provided from home grown feed either as pasture or grazeable complementary forage rotation (CFR in an automatic milking system (AMS. Twelve scenarios consisting of 3 AMS herds (400, 600, 800 cows, 2 levels of pasture utilisation (current AMS utilisation of 15.0 t dry matter [DM]/ha, termed as ‘moderate’; optimum pasture utilisation of 19.7 t DM/ha, termed as ‘high’ and 2 rates of incorporation of grazeable complementary forage system (CFS: 0, 30%; CFS = 65% farm is CFR and 35% of farm is pasture were investigated. Walking distances, energy loss due to walking, MI, reduction in milk yield and income loss were calculated for each treatment based on information available in the literature. With moderate pasture utilisation and 0% CFR, increasing the herd size from 400 to 800 cows resulted in an increase in total walking distances between the parlour and the paddock from 3.5 to 6.3 km. Consequently, MI increased from 15.2 to 16.4 h with increased herd size from 400 to 800 cows. High pasture utilisation (allowing for an increased stocking density reduced the total walking distances up to 1 km, thus reduced the MI by up to 0.5 h compared to the moderate pasture, 800 cow herd combination. The high pasture utilisation combined with 30% of the farm in CFR in the farm reduced the total walking distances by up to 1.7 km and MI by up to 0.8 h compared to the moderate pasture and 800 cow herd combination. For moderate pasture utilisation, increasing the herd size from 400 to 800 cows resulted in more dramatic milk yield penalty as yield increasing from c.f. 2.6 and 5.1 kg/cow/d respectively, which incurred a loss of up to $AU 1.9/cow/d. Milk yield losses of 0.61 kg and 0.25 kg for every km increase in total walking distance

  4. Modelling Pasture-based Automatic Milking System Herds: The Impact of Large Herd on Milk Yield and Economics.

    Science.gov (United States)

    Islam, M R; Clark, C E F; Garcia, S C; Kerrisk, K L

    2015-07-01

    The aim of this modelling study was to investigate the effect of large herd size (and land areas) on walking distances and milking interval (MI), and their impact on milk yield and economic penalties when 50% of the total diets were provided from home grown feed either as pasture or grazeable complementary forage rotation (CFR) in an automatic milking system (AMS). Twelve scenarios consisting of 3 AMS herds (400, 600, 800 cows), 2 levels of pasture utilisation (current AMS utilisation of 15.0 t dry matter [DM]/ha, termed as 'moderate'; optimum pasture utilisation of 19.7 t DM/ha, termed as 'high') and 2 rates of incorporation of grazeable complementary forage system (CFS: 0, 30%; CFS = 65% farm is CFR and 35% of farm is pasture) were investigated. Walking distances, energy loss due to walking, MI, reduction in milk yield and income loss were calculated for each treatment based on information available in the literature. With moderate pasture utilisation and 0% CFR, increasing the herd size from 400 to 800 cows resulted in an increase in total walking distances between the parlour and the paddock from 3.5 to 6.3 km. Consequently, MI increased from 15.2 to 16.4 h with increased herd size from 400 to 800 cows. High pasture utilisation (allowing for an increased stocking density) reduced the total walking distances up to 1 km, thus reduced the MI by up to 0.5 h compared to the moderate pasture, 800 cow herd combination. The high pasture utilisation combined with 30% of the farm in CFR in the farm reduced the total walking distances by up to 1.7 km and MI by up to 0.8 h compared to the moderate pasture and 800 cow herd combination. For moderate pasture utilisation, increasing the herd size from 400 to 800 cows resulted in more dramatic milk yield penalty as yield increasing from c.f. 2.6 and 5.1 kg/cow/d respectively, which incurred a loss of up to $AU 1.9/cow/d. Milk yield losses of 0.61 kg and 0.25 kg for every km increase in total walking distance (voluntary return

  5. Survey of facility and management characteristics of large, Upper Midwest dairy herds clustered by Dairy Herd Improvement records.

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    Brotzman, R L; Döpfer, D; Foy, M R; Hess, J P; Nordlund, K V; Bennett, T B; Cook, N B

    2015-11-01

    A survey of management practices was conducted to investigate potential associations with groupings of herds formed by cluster analysis (CA) of Dairy Herd Improvement (DHI) data of 557 Upper Midwest herds of 200 cows or greater. Differences in herd management practices were identified between the groups, despite underlying similarities; for example, freestall housing and milking in a parlor. Group 6 comprised larger herds with a high proportion of primiparous cows and most frequently utilized practices promoting increased production [e.g., 84.4% used recombinant bovine somatotropin (rbST)], decreased lameness (e.g., 96.9% used routine hoof trimming for cows), and improved efficiency in reproduction [e.g., 93.8% synchronized the first breeding in cows (SYNCH)] and labor (e.g., mean ± SD, 67 ± 19 cows per 50-h per week full-time equivalent worker). Group 1 had the best mean DHI performances and followed most closely group 6 for the rate of adoption of intensive management practices while tending to outperform group 6 despite a generally smaller mean herd size (e.g., 42.3 ± 3.6 kg vs. 39.9 ± 3.6 kg of energy-corrected milk production; 608 ± 352 cows vs. 1,716 ± 1,405 cows). Group 2 were smaller herds with relatively high levels of performance that used less intensive management (e.g., 100% milked twice daily) and less technology (33.3 vs. 73.0% of group 1 used rbST). Group 4 were smaller but poorer-performing herds with low turnover and least frequently used intensive management practices (e.g., 39.1% SYNCH; 30.4% allowed mature, high-producing cows access to pasture). Group 5 used modern technologies and practices associated with improved production, yet had the least desirable mean DHI performance of all 6 groups. This group had the lowest proportion of deep loose-bedded stalls (only 52.2% used sand bedding) and the highest proportion (34.8%) of herds not using routine hoof trimming. The survey of group 3 herds did not reveal strong trends in management. The

  6. Work-Related Musculoskeletal Symptoms and Job Factors Among Large-Herd Dairy Milkers.

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    Douphrate, David I; Nonnenmann, Matthew W; Hagevoort, Robert; Gimeno Ruiz de Porras, David

    2016-01-01

    Dairy production in the United States is moving towards large-herd milking operations, resulting in an increase in task specialization and work demands. The objective of this project was to provide preliminary evidence of the association of a number of specific job conditions that commonly characterize large-herd parlor milking operations with work-related musculoskeletal symptoms (MSS). A modified version of the Standardized Nordic Questionnaire was administered to assess MSS prevalence among 450 US large-herd parlor workers. Worker demographics and MSS prevalences were generated. Prevalence ratios were also generated to determine associations of a number of specific job conditions that commonly characterize large-herd parlor milking operations with work-related MSS. Work-related MSS are prevalent among large-herd parlor workers, since nearly 80% report 12-month prevalences of one or more symptoms, which are primarily located in the upper extremities, specifically shoulders and wrist/hand. Specific large-herd milking parlor job conditions are associated with MSS in multiple body regions, including performing the same task repeatedly, insufficient rest breaks, working when injured, static postures, adverse environmental conditions, and reaching overhead. These findings support the need for administrative and engineering solutions aimed at reducing exposure to job risk factors for work-related MSS among large-herd parlor workers.

  7. Large litter sizes

    DEFF Research Database (Denmark)

    Sandøe, Peter; Rutherford, K.M.D.; Berg, Peer

    2012-01-01

    This paper presents some key results and conclusions from a review (Rutherford et al. 2011) undertaken regarding the ethical and welfare implications of breeding for large litter size in the domestic pig and about different ways of dealing with these implications. Focus is primarily on the direct...... possible to achieve a drop in relative piglet mortality and the related welfare problems. However, there will be a growing problem with the need to use foster or nurse sows which may have negative effects on both sows and piglets. This gives rise to new challenges for management....

  8. Estimating age ratios and size of pacific walrus herds on coastal haulouts using video imaging.

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    Daniel H Monson

    Full Text Available During Arctic summers, sea ice provides resting habitat for Pacific walruses as it drifts over foraging areas in the eastern Chukchi Sea. Climate-driven reductions in sea ice have recently created ice-free conditions in the Chukchi Sea by late summer causing walruses to rest at coastal haulouts along the Chukotka and Alaska coasts, which provides an opportunity to study walruses at relatively accessible locations. Walrus age can be determined from the ratio of tusk length to snout dimensions. We evaluated use of images obtained from a gyro-stabilized video system mounted on a helicopter flying at high altitudes (to avoid disturbance to classify the sex and age of walruses hauled out on Alaska beaches in 2010-2011. We were able to classify 95% of randomly selected individuals to either an 8- or 3-category age class, and we found measurement-based age classifications were more repeatable than visual classifications when using images presenting the correct head profile. Herd density at coastal haulouts averaged 0.88 walruses/m(2 (std. err. = 0.02, herd size ranged from 8,300 to 19,400 (CV 0.03-0.06 and we documented ∼30,000 animals along ∼1 km of beach in 2011. Within the herds, dependent walruses (0-2 yr-olds tended to be located closer to water, and this tendency became more pronounced as the herd spent more time on the beach. Therefore, unbiased estimation of herd age-ratios will require a sampling design that allows for spatial and temporal structuring. In addition, randomly sampling walruses available at the edge of the herd for other purposes (e.g., tagging, biopsying will not sample walruses with an age structure representative of the herd. Sea ice losses are projected to continue, and population age structure data collected with aerial videography at coastal haulouts may provide demographic information vital to ongoing efforts to understand effects of climate change on this species.

  9. Dairy farmers with larger herd sizes adopt more precision dairy technologies.

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    Gargiulo, J I; Eastwood, C R; Garcia, S C; Lyons, N A

    2018-06-01

    An increase in the average herd size on Australian dairy farms has also increased the labor and animal management pressure on farmers, thus potentially encouraging the adoption of precision technologies for enhanced management control. A survey was undertaken in 2015 in Australia to identify the relationship between herd size, current precision technology adoption, and perception of the future of precision technologies. Additionally, differences between farmers and service providers in relation to perception of future precision technology adoption were also investigated. Responses from 199 dairy farmers, and 102 service providers, were collected between May and August 2015 via an anonymous Internet-based questionnaire. Of the 199 dairy farmer responses, 10.4% corresponded to farms that had fewer than 150 cows, 37.7% had 151 to 300 cows, 35.5% had 301 to 500 cows; 6.0% had 501 to 700 cows, and 10.4% had more than 701 cows. The results showed that farmers with more than 500 cows adopted between 2 and 5 times more specific precision technologies, such as automatic cup removers, automatic milk plant wash systems, electronic cow identification systems and herd management software, when compared with smaller farms. Only minor differences were detected in perception of the future of precision technologies between either herd size or farmers and service providers. In particular, service providers expected a higher adoption of automatic milking and walk over weighing systems than farmers. Currently, the adoption of precision technology has mostly been of the type that reduces labor needs; however, respondents indicated that by 2025 adoption of data capturing technology for monitoring farm system parameters would be increased. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  10. The large sample size fallacy.

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    Lantz, Björn

    2013-06-01

    Significance in the statistical sense has little to do with significance in the common practical sense. Statistical significance is a necessary but not a sufficient condition for practical significance. Hence, results that are extremely statistically significant may be highly nonsignificant in practice. The degree of practical significance is generally determined by the size of the observed effect, not the p-value. The results of studies based on large samples are often characterized by extreme statistical significance despite small or even trivial effect sizes. Interpreting such results as significant in practice without further analysis is referred to as the large sample size fallacy in this article. The aim of this article is to explore the relevance of the large sample size fallacy in contemporary nursing research. Relatively few nursing articles display explicit measures of observed effect sizes or include a qualitative discussion of observed effect sizes. Statistical significance is often treated as an end in itself. Effect sizes should generally be calculated and presented along with p-values for statistically significant results, and observed effect sizes should be discussed qualitatively through direct and explicit comparisons with the effects in related literature. © 2012 Nordic College of Caring Science.

  11. Epidemiological study of air filtration systems for preventing PRRSV infection in large sow herds.

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    Alonso, Carmen; Murtaugh, Michael P; Dee, Scott A; Davies, Peter R

    2013-10-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) is the most economically significant pathogen in the US swine industry. Aerosol transmission among herds is a major concern in pig dense regions and filtration of incoming air, in combination with standard biosecurity procedures, has been demonstrated to prevent transmission of PRRSV into susceptible herds. To quantify the impact of air filtration on reducing risk of PRRSV outbreaks, we compared the incidence rate of new PRRSV introductions in 20 filtered and 17 non-filtered control sow herds in a swine dense region of North America during a 7 year study period. Events of novel virus introduction were ascertained by phylogenetic analysis of PRRSV ORF5 gene sequences. Putative new viruses were defined as exogenous (introduced) based on ORF5 nucleotide sequence differences compared to previous farm isolates. The influence of sequence difference cut-off values ranging from 2 to 10% on case definition and relative risk were evaluated. Non-filtered farms incurred about 0.5 outbreaks per year, with a seasonal increase in risk in cooler periods. Baseline risk, prior to filtration, in treatment farms was approximately 0.75 per year, approximately 50% higher than in control farms. Air filtration significantly reduced risk of PRRSV introduction events to 0.06-0.22 outbreaks per year, depending on the cut-off values used to classify a virus isolate as new to the herd. Overall, air filtration led to an approximately 80% reduction in risk of introduction of novel PRRSV, indicating that on large sow farms with good biosecurity in swine-dense regions, approximately four-fifths of PRRSV outbreaks may be attributable to aerosol transmission. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Management, operational, animal health, and economic characteristics of large dairy herds in 4 states in the Upper Midwest of the United States.

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    Evink, T L; Endres, M I

    2017-11-01

    Recent trends in dairy farm structure in the United States have included a decreasing number of farms, although farm size has increased, especially the share of milk production from very large herds (>2,500 cows). The objectives of this observational study were to describe common management practices; to characterize labor and operational structure; to measure some aspects of animal health, including lameness, hock lesions, mortality, and mastitis incidence; and to summarize cost of production on farms with more than 2,500 cows in 4 states in the Upper Midwest of the United States. The study included 15 dairy farms in Minnesota, Wisconsin, Iowa, and South Dakota. Farms were visited twice, once each year, and on-farm herd records were collected for those 2 yr. On-farm herd records were used to investigate mortality, culling, pregnancy rate, and clinical mastitis incidence. At least 1 high-producing pen of mature cows and 1 pen of fresh cows were scored for locomotion. Likewise, at least 1 pen of high-producing mature cows was scored for cleanliness and hock lesions. Median herd size was 3,975 cows (range = 2,606-13,266). Milk sold per employee was 1,120,745 kg and the number of cows per employee was 105. Eighty percent of the farms had Holstein cows, 13% had Jersey, and 7% had Jersey-Holstein crosses. All farms used artificial insemination as the sole form of breeding and 100% of the farms used hormonal synchronization or timed artificial insemination programs in their reproductive protocols; 21-d pregnancy rate was 21.7%. Median lameness prevalence was 18.3% and median severe lameness prevalence was 5.1%. Median hock lesion prevalence was 17.4% and median severe hock lesion prevalence was 1.9%; mortality rate was 7.4%. Clinical mastitis incidence was 62.5 cases per 100 cow-years. Feed costs accounted for approximately 53% of the total cost of producing milk, followed by labor at 11%, interest and depreciation expenses at 10%, and replacement costs at 9.5%. Herds in

  13. Population decline in the Delta caribou herd with reference to other Alaskan herds

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    Patrick Valkenburg et al.

    1996-01-01

    Full Text Available After growing continuously for nearly 15 years, the Delta caribou herd began to decline in 1989. Most other Interior Alaskan herds also began declining. In the Delta herd, and in other herds, the declines were caused primarily by high summer mortality of calves and increased natural mortality of adult females. Other minor causes included increased winter mortality of calves, and reduced parturition rates of 3-year-old and older females. The decline in the Delta herd also coincided with increased wolf (Canis lupus numbers, winters with deeper than normal snow, and warm summers. Mean body weight of annual samples of 10-month-old female calves was consistently low during the decline. Except in some of the smallest Interior Alaskan herds, we conclude that evidence for population regulation in Alaskan caribou is weak, and that herds are likely to fluctuate within a wide range of densities due to complex interactions of predation and weather. Unless wolf numbers are influenced by man, the size of a caribou herd in a given year is likely to be largely a function of its size during the previous population low and the number of years of favorable weather in the interim.

  14. Field Investigation on the Prevalence of Trypanosomiasis in Camels in Relation to Sex, Age, Breed and Herd Size

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    B. Bhutto, J. A. Gadahi, G. Shah1, P. Dewani2 and A.G. Arijo

    2010-07-01

    Full Text Available Blood samples were collected from 240 camels (183 male and 57 female of four breeds from six districts of Sindh. An overall infection was determined as 11.25%. Species of Trypanosoma was identified as Trypanosoma evansi. District wise infection was found to be 2.5, 7.5, 12.5, 15.00, 22.5 and 7.5% in Hyderabad, Mirpur Khas, Umerkot, Badin, Thatta and Larkana, respectively. A higher infection was found in females (15.79% as compared to males (9.84%. Highest (14.96% infection was noted in age group >7 years, followed by 8.57 and 4.65% in 3 to 7 years and less than to 3 years old camels, respectively. Four breeds of camels were surveyed and the highest infection rate was found in Sakrai breed (21.82%, followed by 16.67, 6.15 and 5.95% in Kharai, Sindhi and Dhati breeds respectively. When herd size was considered, infection rate was 1.67, 6.67, 15.00 and 21.67% in herds possessing 1 to 5, 6 to 10, 11 to 20 and more than 20 animals, respectively.

  15. Population dynamics of caribou herds in southwestern Alaska

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    Patrick Valkenburg

    2003-04-01

    Full Text Available The five naturally occurring and one transplanted caribou (Rangifer tarandus granti herd in southwestern Alaska composed about 20% of Alaska's caribou population in 2001. All five of the naturally occurring herds fluctuated considerably in size between the late 1800s and 2001 and for some herds the data provide an indication of long-term periodic (40-50 year fluctuations. At the present time, the Unimak (UCH and Southern Alaska Peninsula (SAP are recovering from population declines, the Northern Alaska Peninsula Herd (NAP appears to be nearing the end of a protracted decline, and the Mulchatna Herd (MCH appears to now be declining after 20 years of rapid growth. The remaining naturally occurring herd (Kilbuck has virtually disappeared. Nutrition had a significant effect on the size of 4-month-old and 10-month-old calves in the NAP and the Nushagak Peninsula Herd (NPCH and probably also on population growth in at least 4 (SAP, NAP, NPCH, and MCH of the six caribou herds in southwestern Alaska. Predation does not appear to be sufficient to keep caribou herds in southwestern Alaska from expanding, probably because rabies is endemic in red foxes (Vulpes vulpes and is periodically transferred to wolves (Canis lupus and other canids. However, we found evidence that pneumonia and hoof rot may result in significant mortality of caribou in southwestern Alaska, whereas there is no evidence that disease is important in the dynamics of Interior herds. Cooperative conservation programs, such as the Kilbuck Caribou Management Plan, can be successful in restraining traditional harvest and promoting growth in caribou herds. In southwestern Alaska we also found evidence that small caribou herds can be swamped and assimilated by large herds, and fidelity to traditional calving areas can be lost.

  16. Prevalence, risk factors and spatial analysis of liver fluke infections in Danish cattle herds

    DEFF Research Database (Denmark)

    Olsen, Abbey; Frankena, Klaas; Bødker, Rene

    2015-01-01

    fitted the observed spatial pattern. Results: During the investigated period (2011-2013), an increase in annual herd prevalence was noted (2011-25.6%; 2012-28.4%; 2013-29.3%). The spatial analysis suggested significant clustering of positive and negative herds. Presence of streams, wetlands and pastures...... on farms showed a significant association with the presence of infection in cattle herds. Buying animals from positive herds was a risk factor on conventional farms. Additionally, risk of being infected with Fasciola hepatica was higher in non-dairy herds of medium size (>= 30 and ... to dairy and large (>= 100) cattle herds. The observed spatial pattern could be reproduced by predictions of the risk factor model. Conclusions: This study showed an increase in annual herd level prevalence (2011 to 2013) indicating that an increasing proportion of herds are infected with Fasciola hepatica...

  17. Consultancy to dairy farmers relating to animal health and herd health management on small- and medium-sized farms.

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    Pothmann, H; Nechanitzky, K; Sturmlechner, F; Drillich, M

    2014-02-01

    The objectives of this study were to obtain information about animal health challenges for dairy farmers of small- and medium-sized herds and about the fields in which consultancy services should be improved. The hyperlink to an internet-based survey was sent to 9,021 farmers in Austria. The survey included questions about the participants and their farms, about who is consulting with the farmers with regard to animal health, feeding, sire selection, construction of barns and animal husbandry, about animal health issues farmers find most challenging, and about their demands for improved consultancy services. The questionnaire was completed anonymously. Analyses were stratified by milk yield (categorized) and whether farmers worked full-time or part-time. The overall response rate was 11.3% (n=1,018). The majority of farms kept less than 20 cows (54.0%) or 20 to 50 cows (40.1%). With regard to animal health, the veterinarian was the most important consultant for the majority of farmers (84.6%). On issues related to feeding, sire selection, and stable construction, the veterinarian was seen as a less important consultant than specialists in these fields (20.4, 11.6, and 7.9% suggested the veterinarian as an important consultant in these areas). The survey indicated that reproductive disorders, udder disease, poor conception rate, lameness, and calf diarrhea represent the most important challenges to farmers. Of these, concerns about calf diarrhea were affected by milk yield of the herds and management. More high- than low-yielding farms (11.7 vs. 6.4%) and more full-time than part-time managed herds (9.6 vs.4.3%) regarded calf diarrhea as an important problem. Farmers would welcome improved consultancy with regard to fertility, feeding, and sire selection. The results indicated which animal health issues farmers find particularly challenging and displayed which areas farmers require improved consultancy services. Veterinarians and organizations offering consultancy

  18. The porcupine caribou herd

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    Griffith, Brad; Douglas, David C.; Walsh, Noreen E.; Young, Donald D.; McCabe, Thomas R.; Russell, Donald E.; White, Robert G.; Cameron, Raymond D.; Whitten, Kenneth R.; Douglas, David C.; Reynolds, Patricia E.; Rhode, E.B.

    2002-01-01

    Documentation of the natural range of variation in ecological, life history, and physiological characteristics of caribou (Rangifer tarandus) of the Porcupine caribou herd is a necessary base for detecting or predicting any potential effects of industrial development on the performance (e.g., distribution, demography, weight-gain of individuals) of the herd. To demonstrate an effect of development, post-development performance must differ from pre-development performance while accounting for any natural environmental trends.We had 2 working hypotheses for our investigations: 1) performance of the Porcupine caribou herd was associated with environmental patterns and habitat quality, and 2) access to important habitats was a key influence on demography.We sought to document the range of natural variation in habitat conditions, herd size, demography (defined here as survival and reproduction), sources and magnitude of mortality, distribution, habitat use, and weight gain and loss, and to develop an understanding of the interactions among these characteristics of the herd.In addition, we investigated ways that we could use this background information, combined with auxiliary information from the adjacent Central Arctic caribou herd, to predict the direction and magnitude of any potential effects of industrial oil development in the 1002 Area of the Arctic National Wildlife Refuge on Porcupine caribou herd calf survival on the herd's calving grounds during June.

  19. Benchmarking dairy herd health status using routinely recorded herd summary data.

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    Parker Gaddis, K L; Cole, J B; Clay, J S; Maltecca, C

    2016-02-01

    Genetic improvement of dairy cattle health through the use of producer-recorded data has been determined to be feasible. Low estimated heritabilities indicate that genetic progress will be slow. Variation observed in lowly heritable traits can largely be attributed to nongenetic factors, such as the environment. More rapid improvement of dairy cattle health may be attainable if herd health programs incorporate environmental and managerial aspects. More than 1,100 herd characteristics are regularly recorded on farm test-days. We combined these data with producer-recorded health event data, and parametric and nonparametric models were used to benchmark herd and cow health status. Health events were grouped into 3 categories for analyses: mastitis, reproductive, and metabolic. Both herd incidence and individual incidence were used as dependent variables. Models implemented included stepwise logistic regression, support vector machines, and random forests. At both the herd and individual levels, random forest models attained the highest accuracy for predicting health status in all health event categories when evaluated with 10-fold cross-validation. Accuracy (SD) ranged from 0.61 (0.04) to 0.63 (0.04) when using random forest models at the herd level. Accuracy of prediction (SD) at the individual cow level ranged from 0.87 (0.06) to 0.93 (0.001) with random forest models. Highly significant variables and key words from logistic regression and random forest models were also investigated. All models identified several of the same key factors for each health event category, including movement out of the herd, size of the herd, and weather-related variables. We concluded that benchmarking health status using routinely collected herd data is feasible. Nonparametric models were better suited to handle this complex data with numerous variables. These data mining techniques were able to perform prediction of health status and could add evidence to personal experience in herd

  20. Large size space construction for space exploitation

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    Kondyurin, Alexey

    2016-07-01

    Space exploitation is impossible without large space structures. We need to make sufficient large volume of pressurized protecting frames for crew, passengers, space processing equipment, & etc. We have to be unlimited in space. Now the size and mass of space constructions are limited by possibility of a launch vehicle. It limits our future in exploitation of space by humans and in development of space industry. Large-size space construction can be made with using of the curing technology of the fibers-filled composites and a reactionable matrix applied directly in free space. For curing the fabric impregnated with a liquid matrix (prepreg) is prepared in terrestrial conditions and shipped in a container to orbit. In due time the prepreg is unfolded by inflating. After polymerization reaction, the durable construction can be fitted out with air, apparatus and life support systems. Our experimental studies of the curing processes in the simulated free space environment showed that the curing of composite in free space is possible. The large-size space construction can be developed. A project of space station, Moon base, Mars base, mining station, interplanet space ship, telecommunication station, space observatory, space factory, antenna dish, radiation shield, solar sail is proposed and overviewed. The study was supported by Humboldt Foundation, ESA (contract 17083/03/NL/SFe), NASA program of the stratospheric balloons and RFBR grants (05-08-18277, 12-08-00970 and 14-08-96011).

  1. Computational scalability of large size image dissemination

    Science.gov (United States)

    Kooper, Rob; Bajcsy, Peter

    2011-01-01

    We have investigated the computational scalability of image pyramid building needed for dissemination of very large image data. The sources of large images include high resolution microscopes and telescopes, remote sensing and airborne imaging, and high resolution scanners. The term 'large' is understood from a user perspective which means either larger than a display size or larger than a memory/disk to hold the image data. The application drivers for our work are digitization projects such as the Lincoln Papers project (each image scan is about 100-150MB or about 5000x8000 pixels with the total number to be around 200,000) and the UIUC library scanning project for historical maps from 17th and 18th century (smaller number but larger images). The goal of our work is understand computational scalability of the web-based dissemination using image pyramids for these large image scans, as well as the preservation aspects of the data. We report our computational benchmarks for (a) building image pyramids to be disseminated using the Microsoft Seadragon library, (b) a computation execution approach using hyper-threading to generate image pyramids and to utilize the underlying hardware, and (c) an image pyramid preservation approach using various hard drive configurations of Redundant Array of Independent Disks (RAID) drives for input/output operations. The benchmarks are obtained with a map (334.61 MB, JPEG format, 17591x15014 pixels). The discussion combines the speed and preservation objectives.

  2. Associations between strain, herd size, age at first calving, culling reason and lifetime performance characteristics in Holstein-Friesian cows.

    Science.gov (United States)

    Adamczyk, K; Makulska, J; Jagusiak, W; Węglarz, A

    2017-02-01

    Cow longevity and lifetime performance traits are good indicators of breeding effectiveness and animal welfare. They are also interrelated with the economics of dairy herd. Unfortunately, a high milk yield is often associated with deteriorated cow health and fertility and, consequently, with an increased culling rate. This situation, observed also in the Polish population of Holstein-Friesian cattle, inspired us to undertake a study on the associations between some factors and lifetime performance characteristics. The data set consisted of the records on 135 496 cows, including 131 526 of the Black and White strain (BW), and 3970 of the Red and White strain (RW) covered by performance recording and culled in 2012. It was found that cows of the BW strain and those from the largest herds (>100 cows) reached higher lifetime and mean daily energy-corrected milk (ECM) yields than cows of the RW strain and those from smaller herds culled at a similar age. Cows youngest at first calving (reasons for cow culling. Cow longevity and lifetime productivity were considerably affected by the interactions between the studied factors.

  3. Mastitis and related management factors in certified organic dairy herds in Sweden

    Directory of Open Access Journals (Sweden)

    Hansson Ingrid

    2006-07-01

    Full Text Available Abstract Background Mastitis is one of the major threats to animal health, in organic farming as well as conventional. Preliminary studies of organic dairy herds have indicated better udder health in such herds, as compared to conventional herds. The aim of this paper was to further study mastitis and management related factors in certified organic dairy herds. Methods An observational study of 26 certified organic dairy herds in mid-eastern Sweden was conducted during one year. A large-animal practitioner visited the herds three times and clinically examined and sampled cows, and collected information about general health and management routines. Data on milk production and disorders treated by a veterinarian in the 26 herds, as well as in 1102 conventional herds, were retrieved from official records. Multivariable logistic regression was used to assess associations between herd type (organic vs. conventional and incidence of disorders. Results The organic herds that took part in the study ranged in size from 12 to 64 cows, in milk production from 3772 to 10334 kg per cow and year, and in bulk milk somatic cell counts from 83000 to 280000 cells/ml. The organic herds were found to have a lower incidence of clinical mastitis, teat injuries, and a lower proportion of cows with a high somatic cell count (as indicated by the UDS, Udder Disease Score compared to conventional herds. The spectrum of udder pathogenic bacteria was similar to that found in other Swedish studies. Treatment of mastitis was found to be similar to what is practised in conventional herds. Homeopathic remedies were not widely used in the treatment of clinical mastitis. The calves in most of these organic herds suckled their dams for only a few days, which were not considered to substantially affect the udder health. The main management factor that was different from conventional herds was the feeding strategy, where organic herds used a larger share of forage. Conclusion Udder

  4. Conception Rate and Litter Size in Multiparous Sows after Intrauterine Insemination Using Frozen-Thawed Boar Semen in a Commercial Swine Herd in Thailand

    OpenAIRE

    CHANAPIWAT, Panida; OLANRATMANEE, Em-On; KAEOKET, Kampon; TUMMARUK, Padet

    2014-01-01

    ABSTRACT The aim of the present study was to determine the conception rate and litter size in sows after fixed time intra-uterine insemination using frozen-thawed boar semen in a commercial swine herd in Thailand. Sixty-nine Landrace multiparous sows were randomly allocated into two groups, including control (n=36) and treatment (n=33). The control sows were inseminated with extended fresh semen (3 × 109 motile sperm/dose, 100 ml) at 24, 36 and 48 hr after the onset of estrus. The treatment s...

  5. Risk factors for displaced abomasum or ketosis in Swedish dairy herds.

    Science.gov (United States)

    Stengärde, L; Hultgren, J; Tråvén, M; Holtenius, K; Emanuelson, U

    2012-03-01

    Risk factors associated with high or low long-term incidence of displaced abomasum (DA) or clinical ketosis were studied in 60 Swedish dairy herds, using multivariable logistic regression modelling. Forty high-incidence herds were included as cases and 20 low-incidence herds as controls. Incidence rates were calculated based on veterinary records of clinical diagnoses. During the 3-year period preceding the herd classification, herds with a high incidence had a disease incidence of DA or clinical ketosis above the 3rd quartile in a national database for disease recordings. Control herds had no cows with DA or clinical ketosis. All herds were visited during the housing period and herdsmen were interviewed about management routines, housing, feeding, milk yield, and herd health. Target groups were heifers in late gestation, dry cows, and cows in early lactation. Univariable logistic regression was used to screen for factors associated with being a high-incidence herd. A multivariable logistic regression model was built using stepwise regression. A higher maximum daily milk yield in multiparous cows and a large herd size (p=0.054 and p=0.066, respectively) tended to be associated with being a high-incidence herd. Not cleaning the heifer feeding platform daily increased the odds of having a high-incidence herd twelvefold (pketosis in Swedish dairy herds. These results confirm the importance of housing, management and feeding in the prevention of metabolic disorders in dairy cows around parturition and in early lactation. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. CLUSTER DYNAMICS LARGELY SHAPES PROTOPLANETARY DISK SIZES

    Energy Technology Data Exchange (ETDEWEB)

    Vincke, Kirsten; Pfalzner, Susanne, E-mail: kvincke@mpifr-bonn.mpg.de [Max Planck Institute for Radio Astronomy, Auf dem Hügel 69, D-53121 Bonn (Germany)

    2016-09-01

    To what degree the cluster environment influences the sizes of protoplanetary disks surrounding young stars is still an open question. This is particularly true for the short-lived clusters typical for the solar neighborhood, in which the stellar density and therefore the influence of the cluster environment change considerably over the first 10 Myr. In previous studies, the effect of the gas on the cluster dynamics has often been neglected; this is remedied here. Using the code NBody6++, we study the stellar dynamics in different developmental phases—embedded, expulsion, and expansion—including the gas, and quantify the effect of fly-bys on the disk size. We concentrate on massive clusters (M {sub cl} ≥ 10{sup 3}–6 ∗ 10{sup 4} M {sub Sun}), which are representative for clusters like the Orion Nebula Cluster (ONC) or NGC 6611. We find that not only the stellar density but also the duration of the embedded phase matters. The densest clusters react fastest to the gas expulsion and drop quickly in density, here 98% of relevant encounters happen before gas expulsion. By contrast, disks in sparser clusters are initially less affected, but because these clusters expand more slowly, 13% of disks are truncated after gas expulsion. For ONC-like clusters, we find that disks larger than 500 au are usually affected by the environment, which corresponds to the observation that 200 au-sized disks are common. For NGC 6611-like clusters, disk sizes are cut-down on average to roughly 100 au. A testable hypothesis would be that the disks in the center of NGC 6611 should be on average ≈20 au and therefore considerably smaller than those in the ONC.

  7. Efficacy of moxidectin against cyathostomins after long-term use in a large herd of draught horses with a high stocking density.

    Science.gov (United States)

    Schumacher, J; Livesey, L; DeGraves, F; Blagburn, B; Ziska, S; Caldwell, M; Brock, K

    2009-05-23

    This study was undertaken to determine whether resistance to moxidectin had developed in a large herd of draught horses, maintained on a small acreage, which had been routinely treated with moxidectin for five years. Faeces were collected for egg counts immediately before moxidectin gel was administered orally, and seven, 30, 60 and 90 days later. The faecal egg counts were significantly reduced at seven and 30 days after treatment, but were not significantly different from pretreatment counts at 60 and 90 days after treatment. There was no evidence of resistance having developed.

  8. Pension funds' herding

    NARCIS (Netherlands)

    Broeders, D.; Chen, D.; Minderhoud, P.; Schudel, W.

    2016-01-01

    This paper uses unique and detailed transaction data to analyse herding behavior among pension funds. We distinguish between weak, semi strong and strong herding behaviour. Weak herding occurs if pension funds have similar rebalancing strategies. Semi strong herding arises when pension funds react

  9. On the surveillance for animal diseases in small herds

    DEFF Research Database (Denmark)

    Greiner, Matthias; Dekker, Aldo

    2005-01-01

    Small herds may present a problem in surveillance for infectious animal diseases because typical levels of a within-herd design prevalence are not directly applicable. We suggest a definition of small herds as those smaller than 2/(within-herd design prevalence) on the basis that such herds would...... be expected to have less than two (i.e. only one) infected animals. Consequently, the probability of detecting small herds cannot be improved by choosing a larger sample size within the herd. We derive necessary sample sizes of herds and the probability ("confidence") of detecting disease within a stratum...... conservative (lower) estimates of the confidence for a given sample size and should therefore be preferred....

  10. Large-sized seaweed monitoring based on MODIS

    Science.gov (United States)

    Ma, Long; Li, Ying; Lan, Guo-xin; Li, Chuan-long

    2009-10-01

    In recent years, large-sized seaweed, such as ulva lactuca, blooms frequently in coastal water in China, which threatens marine eco-environment. In order to take effective measures, it is important to make operational surveillance. A case of large-sized seaweed blooming (i.e. enteromorpha), occurred in June, 2008, in the sea near Qingdao city, is studied. Seaweed blooming is dynamically monitored using Moderate Resolution Imaging Spectroradiometer (MODIS). After analyzing imaging spectral characteristics of enteromorpha, MODIS band 1 and 2 are used to create a band ratio algorithm for detecting and mapping large-sized seaweed blooming. In addition, chlorophyll-α concentration is inversed based on an empirical model developed using MODIS. Chlorophyll-α concentration maps are derived using multitemporal MODIS data, and chlorophyll-α concentration change is analyzed. Results show that the presented methods are useful to get the dynamic distribution and the growth of large-sized seaweed, and can support contingency planning.

  11. Experimental study on propagation properties of large size TEM antennas

    International Nuclear Information System (INIS)

    Zhang Guowei; Wang Haiyang; Chen Weiqing; Wang Wei; Zhu Xiangqin; Xie Linshen

    2014-01-01

    The propagation properties of large size TEM antennas were studied by experiment. The size of the TEM antennas is 60 m × 20 m × 10 m and the character Impedance is 120 Ω. A kind of dielectric foil switch is designed compactly with TEM antennas which can generate double exponential waveform with altitude of 10 kV and rise time of l.2 ns. The radiated field distribution was measured. The relationship between rise time/altitude and distance were provided, and the propagation properties of large size TEM antennas were summarized. (authors)

  12. Conception rate and litter size in multiparous sows after intrauterine insemination using frozen-thawed boar semen in a commercial swine herd in Thailand.

    Science.gov (United States)

    Chanapiwat, Panida; Olanratmanee, Em-On; Kaeoket, Kampon; Tummaruk, Padet

    2014-10-01

    The aim of the present study was to determine the conception rate and litter size in sows after fixed time intra-uterine insemination using frozen-thawed boar semen in a commercial swine herd in Thailand. Sixty-nine Landrace multiparous sows were randomly allocated into two groups, including control (n=36) and treatment (n=33). The control sows were inseminated with extended fresh semen (3 × 10(9) motile sperm/dose, 100 ml) at 24, 36 and 48 hr after the onset of estrus. The treatment sows were inseminated with frozen-thawed semen (2 × 10(9) motile sperm/dose, 20 ml) at 24 and 36 hr after induction of ovulation by human chorionic gonadotropin. All inseminations were carried out by using an intra-uterine insemination technique. The time of ovulation was determined by using transrectal real-time B-mode ultrasonography. The conception rate, farrowing rate, total number of piglets born/litter (TB) and number of piglets born alive/litter (BA) were evaluated. The sows inseminated with extended fresh semen yield a higher TB (10.8 versus 9.0 piglets/l, P=0.015) and tended to have a higher conception rate (88.9% versus 75.8%, P=0.150) than sows inseminated with frozen-thawed semen. In conclusion, insemination using frozen-thawed boar semen can be practiced with convinced fertility under field conditions by fixed-time intrauterine insemination with 2 × 10(9) sperm/ dose of 20 ml at 24 and 36 hr after the onset of estrus.

  13. Conception Rate and Litter Size in Multiparous Sows after Intrauterine Insemination Using Frozen-Thawed Boar Semen in a Commercial Swine Herd in Thailand

    Science.gov (United States)

    CHANAPIWAT, Panida; OLANRATMANEE, Em-On; KAEOKET, Kampon; TUMMARUK, Padet

    2014-01-01

    ABSTRACT The aim of the present study was to determine the conception rate and litter size in sows after fixed time intra-uterine insemination using frozen-thawed boar semen in a commercial swine herd in Thailand. Sixty-nine Landrace multiparous sows were randomly allocated into two groups, including control (n=36) and treatment (n=33). The control sows were inseminated with extended fresh semen (3 × 109 motile sperm/dose, 100 ml) at 24, 36 and 48 hr after the onset of estrus. The treatment sows were inseminated with frozen-thawed semen (2 × 109 motile sperm/dose, 20 ml) at 24 and 36 hr after induction of ovulation by human chorionic gonadotropin. All inseminations were carried out by using an intra-uterine insemination technique. The time of ovulation was determined by using transrectal real-time B-mode ultrasonography. The conception rate, farrowing rate, total number of piglets born/litter (TB) and number of piglets born alive/litter (BA) were evaluated. The sows inseminated with extended fresh semen yield a higher TB (10.8 versus 9.0 piglets/l, P=0.015) and tended to have a higher conception rate (88.9% versus 75.8%, P=0.150) than sows inseminated with frozen-thawed semen. In conclusion, insemination using frozen-thawed boar semen can be practiced with convinced fertility under field conditions by fixed-time intrauterine insemination with 2 × 109 sperm/ dose of 20 ml at 24 and 36 hr after the onset of estrus. PMID:24954517

  14. INFORMATION ASYMMETRY AND HERDING BEHAVIOR

    Directory of Open Access Journals (Sweden)

    Puput Tri Komalasari

    2016-06-01

    Full Text Available Conceptually, the stock market is strong form efficient in the long term. However, in practice, there are various forms of market anomalies that undermine the accuracy of the efficient market hypothesis. One factor suspected as the cause of market inefficiency is herding behavior. Investors herd when they imitate the actions of other investors. This behavior occurs when there is a continuous interaction among rational investors that prevents them from seeking information about market fundamentals. This study provides new insights by including information asymmetry as a moderating variable. This research examines the phenomenon of herding behavior in the Indonesia Stock Exchange as well as examines directly the effect of information asymmetry on herding behavior. The period of study is 2008 using time series of daily stocks data that actively traded in the capital market. Results of this study find that investor tends to follow market consensus when price changes at the low level, but when there is large price swing market participant acts independently from other investors. Interestingly, this study finds that information asymmetry is a necessary condition for the existence of herding behavior.

  15. The influence of herd size, conspecific risk, and predation risk on the vigilance of elk (Cervus elaphus) in Yellowstone National Park, and, Interest, learning, and a thematic biology course

    Science.gov (United States)

    Lung, Mark A.

    This dissertation is a composite of biological and educational research. The biological research concerns Rocky Mountain elk (Cervus elaphus ) behavior. The educational research presents ideas and findings on the influence of a thematic general biology course on student interest and perception of learning. The dissertation begins with a Preface that attempts to bring the ideas presented in later chapters together. Chapter One is a review of the literature concerning sociality, social behaviors, and elk biology. It summarizes current research literature as a means of introduction to Chapter Two. Chapter Two presents findings concerning the effects of herd size, predation risk, and the risk of being near conspecifics on two behaviors commonly associated with social animals---vigilance and aggression. Vigilance and aggression were measured in elk in Yellowstone National Park in two regions that varied in their presence of elk predators (wolves---Canis lupus, and grizzly bears---Ursus arctos) and in two seasons (spring and fall) that varied in the risks of being near conspecifics. Overall, male and female elk responded very differently. Male elk adjust their vigilance and aggression in response to changes in conspecific risk, but not to changes in predation risk. Female elk adjust their vigilance in response to changes in predation risk, but not to changes in conspecific risk. Males show no response in vigilance to changes in herd size. Non-reproductive females, however, adjust their levels of vigilance with changes in herd size in high risk regions. Interestingly, in the spring, vigilance decreases with increasing herd size, but in the fall, vigilance increases with increasing herd size. Chapter Three presents findings concerning the influence of a thematic course design on student perceptions of interest and teaming in a non-major's biology course (Bins 100: Concepts of Biology). I compared responses on student evaluations from two sections of Bios 100 taught in a

  16. Estimated spatial requirements of the medium- to large-sized ...

    African Journals Online (AJOL)

    Conservation planning in the Cape Floristic Region (CFR) of South Africa, a recognised world plant diversity hotspot, required information on the estimated spatial requirements of selected medium- to large-sized mammals within each of 102 Broad Habitat Units (BHUs) delineated according to key biophysical parameters.

  17. Demographic dynamics and off-take of cattle herds in southern Mali.

    Science.gov (United States)

    Ba, Alassane; Lesnoff, Matthieu; Poccard-Chapuis, Rene; Moulin, Charles-Henri

    2011-08-01

    The herds of 95 families were monitored for 1 year in eight villages in the cotton-growing region of southern Mali. In 2006-2007, reproduction performances were average, with 0.54 calvings/year per cow, and mortality was low. Herd numerical productivity is not very high, less than 0.13/year, because of the high proportion of males kept for animal draught. Depending on the herd size, the behaviour of the families differs, in terms of off-take and in-take of animals. Families that only have one or two draught animals seek to increase their animal draught capacity, with a negative net off-take (-0.13/year). Families with two to three cows have a very low net off-take (0.02/year), with culling of adult animals compensated by purchase. They therefore capitalised this year, with an annual herd growth of 8%. Families with a very large herd (20 to 50 cows) take off more of their stock, with a net off-take of 0.08/year (very few animal purchases) and make a stock growth of 5%. And finally, families with an average-sized herd (6 to 19 cows) take off the whole of the year's production, with a net off-take of 0.11/year and a nil stock growth rate. The use of a demographic model made it possible to measure the sensitivity of the productivity rate to the different demographic parameters.

  18. Large exon size does not limit splicing in vivo.

    Science.gov (United States)

    Chen, I T; Chasin, L A

    1994-03-01

    Exon sizes in vertebrate genes are, with a few exceptions, limited to less than 300 bases. It has been proposed that this limitation may derive from the exon definition model of splice site recognition. In this model, a downstream donor site enhances splicing at the upstream acceptor site of the same exon. This enhancement may require contact between factors bound to each end of the exon; an exon size limitation would promote such contact. To test the idea that proximity was required for exon definition, we inserted random DNA fragments from Escherichia coli into a central exon in a three-exon dihydrofolate reductase minigene and tested whether the expanded exons were efficiently spliced. DNA from a plasmid library of expanded minigenes was used to transfect a CHO cell deletion mutant lacking the dhfr locus. PCR analysis of DNA isolated from the pooled stable cotransfectant populations displayed a range of DNA insert sizes from 50 to 1,500 nucleotides. A parallel analysis of the RNA from this population by reverse transcription followed by PCR showed a similar size distribution. Central exons as large as 1,400 bases could be spliced into mRNA. We also tested individual plasmid clones containing exon inserts of defined sizes. The largest exon included in mRNA was 1,200 bases in length, well above the 300-base limit implied by the survey of naturally occurring exons. We conclude that a limitation in exon size is not part of the exon definition mechanism.

  19. Large-scale ocean connectivity and planktonic body size

    KAUST Repository

    Villarino, Ernesto

    2018-01-04

    Global patterns of planktonic diversity are mainly determined by the dispersal of propagules with ocean currents. However, the role that abundance and body size play in determining spatial patterns of diversity remains unclear. Here we analyse spatial community structure - β-diversity - for several planktonic and nektonic organisms from prokaryotes to small mesopelagic fishes collected during the Malaspina 2010 Expedition. β-diversity was compared to surface ocean transit times derived from a global circulation model, revealing a significant negative relationship that is stronger than environmental differences. Estimated dispersal scales for different groups show a negative correlation with body size, where less abundant large-bodied communities have significantly shorter dispersal scales and larger species spatial turnover rates than more abundant small-bodied plankton. Our results confirm that the dispersal scale of planktonic and micro-nektonic organisms is determined by local abundance, which scales with body size, ultimately setting global spatial patterns of diversity.

  20. Large-scale ocean connectivity and planktonic body size

    KAUST Repository

    Villarino, Ernesto; Watson, James R.; Jö nsson, Bror; Gasol, Josep M.; Salazar, Guillem; Acinas, Silvia G.; Estrada, Marta; Massana, Ramó n; Logares, Ramiro; Giner, Caterina R.; Pernice, Massimo C.; Olivar, M. Pilar; Citores, Leire; Corell, Jon; Rodrí guez-Ezpeleta, Naiara; Acuñ a, José Luis; Molina-Ramí rez, Axayacatl; Gonzá lez-Gordillo, J. Ignacio; Có zar, André s; Martí , Elisa; Cuesta, José A.; Agusti, Susana; Fraile-Nuez, Eugenio; Duarte, Carlos M.; Irigoien, Xabier; Chust, Guillem

    2018-01-01

    Global patterns of planktonic diversity are mainly determined by the dispersal of propagules with ocean currents. However, the role that abundance and body size play in determining spatial patterns of diversity remains unclear. Here we analyse spatial community structure - β-diversity - for several planktonic and nektonic organisms from prokaryotes to small mesopelagic fishes collected during the Malaspina 2010 Expedition. β-diversity was compared to surface ocean transit times derived from a global circulation model, revealing a significant negative relationship that is stronger than environmental differences. Estimated dispersal scales for different groups show a negative correlation with body size, where less abundant large-bodied communities have significantly shorter dispersal scales and larger species spatial turnover rates than more abundant small-bodied plankton. Our results confirm that the dispersal scale of planktonic and micro-nektonic organisms is determined by local abundance, which scales with body size, ultimately setting global spatial patterns of diversity.

  1. Accuracy of the photogrametric measuring system for large size elements

    Directory of Open Access Journals (Sweden)

    M. Grzelka

    2011-04-01

    Full Text Available The aim of this paper is to present methods of estimating and guidelines for verifying the accuracy of optical photogrammetric measuringsystems, using for measurement of large size elements. Measuring systems applied to measure workpieces of a large size which oftenreach more than 10000mm require use of appropriate standards. Those standards provided by the manufacturer of photogrammetricsystems are certified and are inspected annually. To make sure that these systems work properly there was developed a special standardVDI / VDE 2634, "Optical 3D measuring systems. Imaging systems with point - by - point probing. " According to recommendationsdescribed in this standard research on accuracy of photogrametric measuring system was conducted using K class gauge blocks dedicatedto calibrate and test accuracy of classic CMMs. The paper presents results of research of estimation the actual error of indication for sizemeasurement MPEE for photogrammetric coordinate measuring system TRITOP.

  2. Prevalence of large endoparasites at necropsy in horses infected with Population B small strongyles in a herd established in Kentucky in 1966.

    Science.gov (United States)

    Lyons, E T; Tolliver, S C; Collins, S S

    2006-07-01

    Two closed horse herds (Old Lot 4 and Field 24), infected since 1966 with Population B small strongyles resistant to thiabendazole (TBZ) and phenothiazine (PTZ), were terminated in February, March, and May, 2005. At necropsy, only the large endoparasites were identified and counted. The number of horses on pasture was 14 (239 days of age to 23 years old) for Old Lot 4 and two (3 to 20 years old) for Field 24. The time of the last antiparasitic treatment, relative to the year (2005) of necropsy, was 26 years for Old Lot 4 and 9 years for Field 24 horses. Gasterophilus intestinalis third instars (three to 113 specimens/horse) were found in all 16 horses and second instars (one to two) in two horses. Gasterophilus nasalis third instars (one to three) were recovered from five horses. Parascaris equorum infections (23 to 144) were in four horses (239 days to 4 years old). Strongylus vulgaris were present in the large intestine (one to 155) of 13 horses from 239 days to 23 years old and in the cranial mesenteric artery (two to 79) in 10 horses from 239 days to 23 years old. Strongylus edentatus were in the large intestine (two to 101) of 12 horses, ranging in age from 2.5 to 23 years old and in the ventral abdominal wall (one to 53) of six horses from 239 days to 21 years old. Specimens (seven to 872) of Anoplocephala perfoliata were in all horses. Oxyuris equi (one to 129) were recovered from seven horses (330 days to 23 years old). Thelazia lacrymalis (one to 85) infected the eyes of five horses (317 days to 11 years old).

  3. Processing and properties of large-sized ceramic slabs

    Energy Technology Data Exchange (ETDEWEB)

    Raimondo, M.; Dondi, M.; Zanelli, C.; Guarini, G.; Gozzi, A.; Marani, F.; Fossa, L.

    2010-07-01

    Large-sized ceramic slabs with dimensions up to 360x120 cm{sup 2} and thickness down to 2 mm are manufactured through an innovative ceramic process, starting from porcelain stoneware formulations and involving wet ball milling, spray drying, die-less slow-rate pressing, a single stage of fast drying-firing, and finishing (trimming, assembling of ceramic-fiberglass composites). Fired and unfired industrial slabs were selected and characterized from the technological, compositional (XRF, XRD) and microstructural (SEM) viewpoints. Semi-finished products exhibit a remarkable microstructural uniformity and stability in a rather wide window of firing schedules. The phase composition and compact microstructure of fired slabs are very similar to those of porcelain stoneware tiles. The values of water absorption, bulk density, closed porosity, functional performances as well as mechanical and tribological properties conform to the top quality range of porcelain stoneware tiles. However, the large size coupled with low thickness bestow on the slab a certain degree of flexibility, which is emphasized in ceramic-fiberglass composites. These outstanding performances make the large-sized slabs suitable to be used in novel applications: building and construction (new floorings without dismantling the previous paving, ventilated facades, tunnel coverings, insulating panelling), indoor furnitures (table tops, doors), support for photovoltaic ceramic panels. (Author) 24 refs.

  4. Processing and properties of large-sized ceramic slabs

    International Nuclear Information System (INIS)

    Raimondo, M.; Dondi, M.; Zanelli, C.; Guarini, G.; Gozzi, A.; Marani, F.; Fossa, L.

    2010-01-01

    Large-sized ceramic slabs with dimensions up to 360x120 cm 2 and thickness down to 2 mm are manufactured through an innovative ceramic process, starting from porcelain stoneware formulations and involving wet ball milling, spray drying, die-less slow-rate pressing, a single stage of fast drying-firing, and finishing (trimming, assembling of ceramic-fiberglass composites). Fired and unfired industrial slabs were selected and characterized from the technological, compositional (XRF, XRD) and microstructural (SEM) viewpoints. Semi-finished products exhibit a remarkable microstructural uniformity and stability in a rather wide window of firing schedules. The phase composition and compact microstructure of fired slabs are very similar to those of porcelain stoneware tiles. The values of water absorption, bulk density, closed porosity, functional performances as well as mechanical and tribological properties conform to the top quality range of porcelain stoneware tiles. However, the large size coupled with low thickness bestow on the slab a certain degree of flexibility, which is emphasized in ceramic-fiberglass composites. These outstanding performances make the large-sized slabs suitable to be used in novel applications: building and construction (new floorings without dismantling the previous paving, ventilated facades, tunnel coverings, insulating panelling), indoor furnitures (table tops, doors), support for photovoltaic ceramic panels. (Author) 24 refs.

  5. Technological Aspects of Creating Large-size Optical Telescopes

    Directory of Open Access Journals (Sweden)

    V. V. Sychev

    2015-01-01

    Full Text Available A concept of the telescope creation, first of all, depends both on a choice of the optical scheme to form optical radiation and images with minimum losses of energy and information and on a choice of design to meet requirements for strength, stiffness, and stabilization characteristics in real telescope operation conditions. Thus, the concept of creating large-size telescopes, certainly, involves the use of adaptive optics methods and means.The level of technological capabilities to realize scientific and engineering ideas define a successful development of large-size optical telescopes in many respects. All developers pursue the same aim that is to raise an amount of information by increasing a main mirror diameter of the telescope.The article analyses the adaptive telescope designs developed in our country. Using a domestic ACT-25 telescope as an example, it considers creation of large-size optical telescopes in terms of technological aspects. It also describes the telescope creation concept features, which allow reaching marginally possible characteristics to ensure maximum amount of information.The article compares a wide range of large-size telescopes projects. It shows that a domestic project to create the adaptive ACT-25 super-telescope surpasses its foreign counterparts, and there is no sense to implement Euro50 (50m and OWL (100m projects.The considered material gives clear understanding on a role of technological aspects in development of such complicated optic-electronic complexes as a large-size optical telescope. The technological criteria of an assessment offered in the article, namely specific informational content of the telescope, its specific mass, and specific cost allow us to reveal weaknesses in the project development and define a reserve regarding further improvement of the telescope.The analysis of results and their judgment have shown that improvement of optical largesize telescopes in terms of their maximum

  6. Predation rate by wolves on the Porcupine caribou herd

    Directory of Open Access Journals (Sweden)

    Robert D. Hayes

    2000-04-01

    Full Text Available Large migratory catibou {Rangifer tarandus herds in the Arctic tend to be cyclic, and population trends are mainly driven by changes in forage or weather events, not by predation. We estimated daily kill rate by wolves on adult caribou in winter, then constructed a time and space dependent model to estimate annual wolf (Canis lupus predation rate (P annual on adult Porcupine caribou. Our model adjusts predation seasonally depending on caribou distribution: Pannual = SIGMAdaily* W *Ap(2*Dp. In our model we assumed that wolves killed adult caribou at a constant rate (Kdaily, 0.08 caribou wolf1 day1 based on our studies and elsewhere; that wolf density (W doubled to 6 wolves 1000 km2-1 on all seasonal ranges; and that the average area occupied by the Porcupine caribou herd (PCH in eight seasonal life cycle periods (Dp was two times gteater than the area described by the outer boundaries of telemetry data (Ap /1000 km2. Results from our model projected that wolves kill about 7600 adult caribou each year, regardless of herd size. The model estimated that wolves removed 5.8 to 7.4% of adult caribou as the herd declined in the 1990s. Our predation rate model supports the hypothesis of Bergerud that spacing away by caribou is an effective anti-predatory strategy that greatly reduces wolf predation on adult caribou in the spring and summer.

  7. Higher albedos and size distribution of large transneptunian objects

    Science.gov (United States)

    Lykawka, Patryk Sofia; Mukai, Tadashi

    2005-11-01

    Transneptunian objects (TNOs) orbit beyond Neptune and do offer important clues about the formation of our solar system. Although observations have been increasing the number of discovered TNOs and improving their orbital elements, very little is known about elementary physical properties such as sizes, albedos and compositions. Due to TNOs large distances (>40 AU) and observational limitations, reliable physical information can be obtained only from brighter objects (supposedly larger bodies). According to size and albedo measurements available, it is evident the traditionally assumed albedo p=0.04 cannot hold for all TNOs, especially those with approximately absolute magnitudes H⩽5.5. That is, the largest TNOs possess higher albedos (generally >0.04) that strongly appear to increase as a function of size. Using a compilation of published data, we derived empirical relations which can provide estimations of diameters and albedos as a function of absolute magnitude. Calculations result in more accurate size/albedo estimations for TNOs with H⩽5.5 than just assuming p=0.04. Nevertheless, considering low statistics, the value p=0.04 sounds still convenient for H>5.5 non-binary TNOs as a group. We also discuss about physical processes (e.g., collisions, intrinsic activity and the presence of tenuous atmospheres) responsible for the increase of albedo among large bodies. Currently, all big TNOs (>700 km) would be capable to sustain thin atmospheres or icy frosts composed of CH 4, CO or N 2 even for body bulk densities as low as 0.5 g cm -3. A size-dependent albedo has important consequences for the TNOs size distribution, cumulative luminosity function and total mass estimations. According to our analysis, the latter can be reduced up to 50% if higher albedos are common among large bodies. Lastly, by analyzing orbital properties of classical TNOs ( 42AUbodies. For both populations, distinct absolute magnitude distributions are maximized for an inclination threshold

  8. Endometritis treatment with a PGF2alpha analog does not improve reproductive performance in a large dairy herd in Argentina.

    Science.gov (United States)

    Mejía, Miguel Eduardo; Lacau-Mengido, Isabel María

    2005-03-15

    In Argentina, most dairy cows with endometritis are treated with prostaglandin (PGF(2alpha) or its analogs) and insemination is withheld until there are no signs of endometritis. The objective of the present study was to evaluate if this method of managing endometritis enhances reproductive performance. Three experiments were conducted over 4 years in a large farm in the west of Buenos Aires province. In Experiment 1, half of the cows diagnosed with endometritis (>1.5-fold difference in diameter of uterine horns, as determined by rectal palpation) received standard endometritis management (treatment with tiaprost, a PGF(2alpha) analog, rectal palpation every 20 days, and withholding of AI until endometritis apparently resolved) and the other half was untreated, with AI at the first estrus after the voluntary waiting period. Untreated cows were inseminated and conceived 20 days earlier than treated cows, and the pregnancy rate by Day 90 postpartum was higher in the untreated group. In Experiment 2, cows with endometritis were divided into four groups according to the severity of symptoms; within each group, cows were allocated to treatment or control, as in Experiment 1. Although first service conception rate decreased as endometritis severity increased, reproductive performance in treated versus control cows was similar to that of Experiment 1 (with no interaction due to degree of endometritis). Re-evaluation of the treated cow (to confirm uterine "normality") may have been responsible for the delay in conception in both experiments. The objective of Experiment 3 was to determine the effects of tiaprost treatment on clinically normal postpartum cows (no evidence of endometritis). Tiaprost treatment reduced the interval from calving to conception in multiparous cows, but it delayed conception and reduced the conception rate in primiparous cows. In conclusion, treatment with tiaprost impaired reproductive performance in primiparous cows (in the absence of

  9. Phased array inspection of large size forged steel parts

    Science.gov (United States)

    Dupont-Marillia, Frederic; Jahazi, Mohammad; Belanger, Pierre

    2018-04-01

    High strength forged steel requires uncompromising quality to warrant advance performance for numerous critical applications. Ultrasonic inspection is commonly used in nondestructive testing to detect cracks and other defects. In steel blocks of relatively small dimensions (at least two directions not exceeding a few centimetres), phased array inspection is a trusted method to generate images of the inside of the blocks and therefore identify and size defects. However, casting of large size forged ingots introduces changes of mechanical parameters such as grain size, the Young's modulus, the Poisson's ratio, and the chemical composition. These heterogeneities affect the wave propagation, and consequently, the reliability of ultrasonic inspection and the imaging capabilities for these blocks. In this context, a custom phased array transducer designed for a 40-ton bainitic forged ingot was investigated. Following a previous study that provided local mechanical parameters for a similar block, two-dimensional simulations were made to compute the optimal transducer parameters including the pitch, width and number of elements. It appeared that depending on the number of elements, backwall reconstruction can generate high amplitude artefacts. Indeed, the large dimensions of the simulated block introduce numerous constructive interferences from backwall reflections which may lead to important artefacts. To increase image quality, the reconstruction algorithm was adapted and promising results were observed and compared with the scattering cone filter method available in the CIVA software.

  10. Reliable pipeline repair system for very large pipe size

    Energy Technology Data Exchange (ETDEWEB)

    Charalambides, John N.; Sousa, Alexandre Barreto de [Oceaneering International, Inc., Houston, TX (United States)

    2004-07-01

    The oil and gas industry worldwide has been mainly depending on the long-term reliability of rigid pipelines to ensure the transportation of hydrocarbons, crude oil, gas, fuel, etc. Many other methods are also utilized onshore and offshore (e.g. flexible lines, FPSO's, etc.), but when it comes to the underwater transportation of very high volumes of oil and gas, the industry commonly uses large size rigid pipelines (i.e. steel pipes). Oil and gas operators learned to depend on the long-lasting integrity of these very large pipelines and many times they forget or disregard that even steel pipelines degrade over time and more often that that, they are also susceptible to various forms of damage (minor or major, environmental or external, etc.). Over the recent years the industry had recognized the need of implementing an 'emergency repair plan' to account for such unforeseen events and the oil and gas operators have become 'smarter' by being 'pro-active' in order to ensure 'flow assurance'. When we consider very large diameter steel pipelines such as 42' and 48' nominal pipe size (NPS), the industry worldwide does not provide 'ready-made', 'off-the-shelf' repair hardware that can be easily shipped to the offshore location and effect a major repair within acceptable time frames and avoid substantial profit losses due to 'down-time' in production. The typical time required to establish a solid repair system for large pipe diameters could be as long as six or more months (depending on the availability of raw materials). This paper will present in detail the Emergency Pipeline Repair Systems (EPRS) that Oceaneering successfully designed, manufactured, tested and provided to two major oil and gas operators, located in two different continents (Gulf of Mexico, U.S.A. and Arabian Gulf, U.A.E.), for two different very large pipe sizes (42'' and 48'' Nominal Pipe Sizes

  11. Seroprevalence of border disease in Danish sheep and goat herds

    DEFF Research Database (Denmark)

    Tegtmeier, C.; Stryhn, H.; Uttenthal, Åse

    2000-01-01

    A study was conducted in 1994-96 with the aim of assessing the serological prevalence of Border Disease (BD) among sheep and goats in Denmark and to investigate possible relations to herd factors. From each of 1000 herds, 2 blood samples were obtained from animals older than 1 year. The examination.......50. There was no difference between the prevalence in sheep and goat herds. Records for well over half of the herds could be combined with data from the Danish Central Husbandry Register. No association between occurrence of ED and herd size was found. Cattle were registered as contemporarily present on 135 out of 521 herds...... which was shown to be strongly associated to ED. The estimated herd prevalences of ED among farms with and without contemporary cattle were 0.24 and 0.042, respectively....

  12. Ecology of the Porcupine caribou herd

    Directory of Open Access Journals (Sweden)

    Kenneth R. Whitten

    1996-01-01

    Full Text Available Researchers have described general patterns of population regulation that fit most caribou (Rangifer tarandus herds. Nevertheless, specific factors operating on particular populations vary greatly, and efforts to categorize herds according to the general patterns often lead to confusion. It is difficult for biologists to attempt to describe population dynamics in terms of density relationships for wide-ranging arctic caribou such as the Porcupine Herd. In these herds density varies as a function of dispersal and erratic movement patterns and is not simply the number of caribou divided by a fixed range area. Density is also a poor surrogate for resource availability per individual caribou because climatic factors affect forage and/or access to forage independendy of caribou numbers. Thus classic signs of nutritional stress such as delayed puberty, reduced productivity, and winter starvation can occur when a population is small as well as large and do not necessarily denote food competition brought on by high density, per se. Nutritional stress and exacerbated predation due to adverse weather conditions occasionally cause the Porcupine Herd to decline, and limiting factors such as poor nutrition, predation, harvest, accidents, and disease act in combination to keep herd growth rates low during periods of good weather. Adverse weather setbacks occur frequently, and the herd remains within a fairly restricted range of densities over long time periods. There is no true density dependent regulation and no equilibrium in this system.

  13. Vertebral Adaptations to Large Body Size in Theropod Dinosaurs.

    Directory of Open Access Journals (Sweden)

    John P Wilson

    Full Text Available Rugose projections on the anterior and posterior aspects of vertebral neural spines appear throughout Amniota and result from the mineralization of the supraspinous and interspinous ligaments via metaplasia, the process of permanent tissue-type transformation. In mammals, this metaplasia is generally pathological or stress induced, but is a normal part of development in some clades of birds. Such structures, though phylogenetically sporadic, appear throughout the fossil record of non-avian theropod dinosaurs, yet their physiological and adaptive significance has remained unexamined. Here we show novel histologic and phylogenetic evidence that neural spine projections were a physiological response to biomechanical stress in large-bodied theropod species. Metaplastic projections also appear to vary between immature and mature individuals of the same species, with immature animals either lacking them or exhibiting smaller projections, supporting the hypothesis that these structures develop through ontogeny as a result of increasing bending stress subjected to the spinal column. Metaplastic mineralization of spinal ligaments would likely affect the flexibility of the spinal column, increasing passive support for body weight. A stiff spinal column would also provide biomechanical support for the primary hip flexors and, therefore, may have played a role in locomotor efficiency and mobility in large-bodied species. This new association of interspinal ligament metaplasia in Theropoda with large body size contributes additional insight to our understanding of the diverse biomechanical coping mechanisms developed throughout Dinosauria, and stresses the significance of phylogenetic methods when testing for biological trends, evolutionary or not.

  14. Vertebral Adaptations to Large Body Size in Theropod Dinosaurs.

    Science.gov (United States)

    Wilson, John P; Woodruff, D Cary; Gardner, Jacob D; Flora, Holley M; Horner, John R; Organ, Chris L

    2016-01-01

    Rugose projections on the anterior and posterior aspects of vertebral neural spines appear throughout Amniota and result from the mineralization of the supraspinous and interspinous ligaments via metaplasia, the process of permanent tissue-type transformation. In mammals, this metaplasia is generally pathological or stress induced, but is a normal part of development in some clades of birds. Such structures, though phylogenetically sporadic, appear throughout the fossil record of non-avian theropod dinosaurs, yet their physiological and adaptive significance has remained unexamined. Here we show novel histologic and phylogenetic evidence that neural spine projections were a physiological response to biomechanical stress in large-bodied theropod species. Metaplastic projections also appear to vary between immature and mature individuals of the same species, with immature animals either lacking them or exhibiting smaller projections, supporting the hypothesis that these structures develop through ontogeny as a result of increasing bending stress subjected to the spinal column. Metaplastic mineralization of spinal ligaments would likely affect the flexibility of the spinal column, increasing passive support for body weight. A stiff spinal column would also provide biomechanical support for the primary hip flexors and, therefore, may have played a role in locomotor efficiency and mobility in large-bodied species. This new association of interspinal ligament metaplasia in Theropoda with large body size contributes additional insight to our understanding of the diverse biomechanical coping mechanisms developed throughout Dinosauria, and stresses the significance of phylogenetic methods when testing for biological trends, evolutionary or not.

  15. Assessment of Structural Traits and Management Related to Dairy Herds in the Peri-urban Area of Bobo Dioulasso (South West of Burkina Faso

    Directory of Open Access Journals (Sweden)

    M. Mattoni

    2007-04-01

    Full Text Available To define mean herd size, structural traits, animal sourcing and use, management and aspects related to the milk production, 118 dairy herds, involved in a FAO dairy development project were studied. The mean herd size after allocation to clusters: Small (≤38 heads, Medium (>38, ≤61 heads and Large (>61 heads was 52.8±25.8, ranging from 7 to 134 heads of cattle. The following genotypes: Cross bred (CR 58.8%, Zebu (ZB 23.2% and Taurine cattle (TA 18.0% which were not uniformly distributed neither across nor within herds were identified. Sex ratio was two thirds of females (70.6%, one third of males (28.1% and a low proportion (1.3% of castrated males. No mature TA males compared to 53.3% of the male ZB and 31.4% of the male CR, were indicated as potential sires. Investments in purchase of animals were higher in Small than in Medium and Large herds; of all purchased sires 53.8% were found in Small herds vs. 28.2% and 18.0% in Medium and Large. Herd property was equally distributed between single (56.8% and multi property (43.2%. There was more manpower available per 100 cows in Small, being almost double and triple than in Medium and Large herds. Although milk extracted, was similar in all clusters averaging 2.4±0.5 litres/day/cow, milk off take rate, due to higher proportion of lactating cows, appeared higher in Small herds.

  16. BAND STRUCTURE OF NON-STEIOCHIOMETRIC LARGE-SIZED NANOCRYSTALLITES

    Directory of Open Access Journals (Sweden)

    I.V.Kityk

    2004-01-01

    Full Text Available A band structure of large-sized (from 20 to 35nm non-steichiometric nanocrystallites (NC of the Si2-xCx (1.04 < x < 1.10 has been investigated using different band energy approaches and a modified Car-Parinello molecular dynamics structure optimization of the NC interfaces. The non-steichiometric excess of carbon favors the appearance of a thin prevailingly carbon-contained layer (with thickness of about 1 nm covering the crystallites. As a consequence, one can observe a substantial structure reconstruction of boundary SiC crystalline layers. The numerical modeling has shown that these NC can be considered as SiC reconstructed crystalline films with thickness of about 2 nm covering the SiC crystallites. The observed data are considered within the different one-electron band structure methods. It was shown that the nano-sized carbon sheet plays a key role in a modified band structure. Independent manifestation of the important role played by the reconstructed confined layers is due to the experimentally discovered excitonic-like resonances. Low-temperature absorption measurements confirm the existence of sharp-like absorption resonances originating from the reconstructed layers.

  17. An alternative method for determining particle-size distribution of forest road aggregate and soil with large-sized particles

    Science.gov (United States)

    Hakjun Rhee; Randy B. Foltz; James L. Fridley; Finn Krogstad; Deborah S. Page-Dumroese

    2014-01-01

    Measurement of particle-size distribution (PSD) of soil with large-sized particles (e.g., 25.4 mm diameter) requires a large sample and numerous particle-size analyses (PSAs). A new method is needed that would reduce time, effort, and cost for PSAs of the soil and aggregate material with large-sized particles. We evaluated a nested method for sampling and PSA by...

  18. New Sequences with Low Correlation and Large Family Size

    Science.gov (United States)

    Zeng, Fanxin

    In direct-sequence code-division multiple-access (DS-CDMA) communication systems and direct-sequence ultra wideband (DS-UWB) radios, sequences with low correlation and large family size are important for reducing multiple access interference (MAI) and accepting more active users, respectively. In this paper, a new collection of families of sequences of length pn-1, which includes three constructions, is proposed. The maximum number of cyclically distinct families without GMW sequences in each construction is φ(pn-1)/n·φ(pm-1)/m, where p is a prime number, n is an even number, and n=2m, and these sequences can be binary or polyphase depending upon choice of the parameter p. In Construction I, there are pn distinct sequences within each family and the new sequences have at most d+2 nontrivial periodic correlation {-pm-1, -1, pm-1, 2pm-1,…,dpm-1}. In Construction II, the new sequences have large family size p2n and possibly take the nontrivial correlation values in {-pm-1, -1, pm-1, 2pm-1,…,(3d-4)pm-1}. In Construction III, the new sequences possess the largest family size p(d-1)n and have at most 2d correlation levels {-pm-1, -1,pm-1, 2pm-1,…,(2d-2)pm-1}. Three constructions are near-optimal with respect to the Welch bound because the values of their Welch-Ratios are moderate, WR_??_d, WR_??_3d-4 and WR_??_2d-2, respectively. Each family in Constructions I, II and III contains a GMW sequence. In addition, Helleseth sequences and Niho sequences are special cases in Constructions I and III, and their restriction conditions to the integers m and n, pm≠2 (mod 3) and n≅0 (mod 4), respectively, are removed in our sequences. Our sequences in Construction III include the sequences with Niho type decimation 3·2m-2, too. Finally, some open questions are pointed out and an example that illustrates the performance of these sequences is given.

  19. Sizing the star cluster population of the Large Magellanic Cloud

    Science.gov (United States)

    Piatti, Andrés E.

    2018-04-01

    The number of star clusters that populate the Large Magellanic Cloud (LMC) at deprojected distances knowledge of the LMC cluster formation and dissolution histories, we closely revisited such a compilation of objects and found that only ˜35 per cent of the previously known catalogued clusters have been included. The remaining entries are likely related to stellar overdensities of the LMC composite star field, because there is a remarkable enhancement of objects with assigned ages older than log(t yr-1) ˜ 9.4, which contrasts with the existence of the LMC cluster age gap; the assumption of a cluster formation rate similar to that of the LMC star field does not help to conciliate so large amount of clusters either; and nearly 50 per cent of them come from cluster search procedures known to produce more than 90 per cent of false detections. The lack of further analyses to confirm the physical reality as genuine star clusters of the identified overdensities also glooms those results. We support that the actual size of the LMC main body cluster population is close to that previously known.

  20. Processing and properties of large-sized ceramic slabs

    Directory of Open Access Journals (Sweden)

    Fossa, L.

    2010-10-01

    Full Text Available Large-sized ceramic slabs – with dimensions up to 360x120 cm2 and thickness down to 2 mm – are manufactured through an innovative ceramic process, starting from porcelain stoneware formulations and involving wet ball milling, spray drying, die-less slow-rate pressing, a single stage of fast drying-firing, and finishing (trimming, assembling of ceramic-fiberglass composites. Fired and unfired industrial slabs were selected and characterized from the technological, compositional (XRF, XRD and microstructural (SEM viewpoints. Semi-finished products exhibit a remarkable microstructural uniformity and stability in a rather wide window of firing schedules. The phase composition and compact microstructure of fired slabs are very similar to those of porcelain stoneware tiles. The values of water absorption, bulk density, closed porosity, functional performances as well as mechanical and tribological properties conform to the top quality range of porcelain stoneware tiles. However, the large size coupled with low thickness bestow on the slab a certain degree of flexibility, which is emphasized in ceramic-fiberglass composites. These outstanding performances make the large-sized slabs suitable to be used in novel applications: building and construction (new floorings without dismantling the previous paving, ventilated façades, tunnel coverings, insulating panelling, indoor furnitures (table tops, doors, support for photovoltaic ceramic panels.

    Se han fabricado piezas de gran formato, con dimensiones de hasta 360x120 cm, y menos de 2 mm, de espesor, empleando métodos innovadores de fabricación, partiendo de composiciones de gres porcelánico y utilizando, molienda con bolas por vía húmeda, atomización, prensado a baja velocidad sin boquilla de extrusión, secado y cocción rápido en una sola etapa, y un acabado que incluye la adhesión de fibra de vidrio al soporte cerámico y el rectificado de la pieza final. Se han

  1. High voltage distribution scheme for large size GEM detector

    International Nuclear Information System (INIS)

    Saini, J.; Kumar, A.; Dubey, A.K.; Negi, V.S.; Chattopadhyay, S.

    2016-01-01

    Gas Electron Multiplier (GEM) detectors will be used for Muon tracking in the Compressed Baryonic Matter (CBM) experiment at the Facility for Anti-proton Ion Research (FAIR) at Darmstadt, Germany. The sizes of the detector modules in the Muon chambers are of the order of 1 metre x 0.5 metre. For construction of these chambers, three GEM foils are used per chamber. These foils are made by two layered 50μm thin kapton foil. Each GEM foil has millions of holes on it. In such a large scale manufacturing of the foils, even after stringent quality controls, some of the holes may still have defects or defects might develop over the time with operating conditions. These defects may result in short-circuit of the entire GEM foil. A short even in a single hole will make entire foil un-usable. To reduce such occurrences, high voltage (HV) segmentation within the foils has been introduced. These segments are powered either by individual HV supply per segment or through an active HV distribution to manage such a large number of segments across the foil. Individual supplies apart from being costly, are highly complex to implement. Additionally, CBM will have high intensity of particles bombarding on the detector causing the change of resistive chain current feeding the GEM detector with the variation in the intensity. This leads to voltage fluctuations across the foil resulting in the gain variation with the particle intensity. Hence, a low cost active HV distribution is designed to take care of the above discussed issues

  2. Large-size space debris flyby in low earth orbits

    Science.gov (United States)

    Baranov, A. A.; Grishko, D. A.; Razoumny, Y. N.

    2017-09-01

    the analysis of NORAD catalogue of space objects executed with respect to the overall sizes of upper-stages and last stages of carrier rockets allows the classification of 5 groups of large-size space debris (LSSD). These groups are defined according to the proximity of orbital inclinations of the involved objects. The orbits within a group have various values of deviations in the Right Ascension of the Ascending Node (RAAN). It is proposed to use the RAANs deviations' evolution portrait to clarify the orbital planes' relative spatial distribution in a group so that the RAAN deviations should be calculated with respect to the concrete precessing orbital plane of the concrete object. In case of the first three groups (inclinations i = 71°, i = 74°, i = 81°) the straight lines of the RAAN relative deviations almost do not intersect each other. So the simple, successive flyby of group's elements is effective, but the significant value of total Δ V is required to form drift orbits. In case of the fifth group (Sun-synchronous orbits) these straight lines chaotically intersect each other for many times due to the noticeable differences in values of semi-major axes and orbital inclinations. The intersections' existence makes it possible to create such a flyby sequence for LSSD group when the orbit of one LSSD object simultaneously serves as the drift orbit to attain another LSSD object. This flyby scheme requiring less Δ V was called "diagonal." The RAANs deviations' evolution portrait built for the fourth group (to be studied in the paper) contains both types of lines, so the simultaneous combination of diagonal and successive flyby schemes is possible. The value of total Δ V and temporal costs were calculated to cover all the elements of the 4th group. The article is also enriched by the results obtained for the flyby problem solution in case of all the five mentioned LSSD groups. The general recommendations are given concerned with the required reserve of total

  3. The influence of selected litter and herd factors on treatments for lameness in suckling piglets from 35 Danish herds

    DEFF Research Database (Denmark)

    Christensen, J.

    1996-01-01

    was: high-risk litters are (1) large litters, (2) litters with previous diseases or deaths, (3) litters where the nursing sow had been treated, or (4) litters from high-parity sows. Litters from large conventional herds or from herds with a high stocking density were expected to have a high risk...

  4. Visual exposure to large and small portion sizes and perceptions of portion size normality: Three experimental studies

    OpenAIRE

    Robinson, Eric; Oldham, Melissa; Cuckson, Imogen; Brunstrom, Jeffrey M.; Rogers, Peter J.; Hardman, Charlotte A.

    2016-01-01

    Portion sizes of many foods have increased in recent times. In three studies we examined the effect that repeated visual exposure to larger versus smaller food portion sizes has on perceptions of what constitutes a normal-sized food portion and measures of portion size selection. In studies 1 and 2 participants were visually exposed to images of large or small portions of spaghetti bolognese, before making evaluations about an image of an intermediate sized portion of the same food. In study ...

  5. Herd prevalence of bovine brucellosis and analysis of risk factors in cattle in urban and peri-urban areas of the Kampala economic zone, Uganda

    Directory of Open Access Journals (Sweden)

    Eisler Mark C

    2011-10-01

    Full Text Available Abstract Background Human brucellosis has been found to be prevalent in the urban areas of Kampala, the capital city of Uganda. A cross-sectional study was designed to generate precise information on the prevalence of brucellosis in cattle and risk factors for the disease in its urban and peri-urban dairy farming systems. Results The adjusted herd prevalence of brucellosis was 6.5% (11/177, 95% CI: 3.6%-10.0% and the adjusted individual animal prevalence was 5.0% (21/423, 95% CI: 2.7% - 9.3% based on diagnosis using commercial kits of the competitive enzyme-linked immunosorbent assay (CELISA for Brucella abortus antibodies. Mean within-herd prevalence was found to be 25.9% (95% CI: 9.7% - 53.1% and brucellosis prevalence in an infected herd ranged from 9.1% to 50%. A risk factor could not be identified at the animal level but two risk factors were identified at the herd level: large herd size and history of abortion. The mean number of milking cows in a free-grazing herd (5.0 was significantly larger than a herd with a movement restricted (1.7, p Conclusions Vaccination should be targeted at commercial large-scale farms with free-grazing farming to control brucellosis in cattle in and around Kampala city.

  6. Multifractality and herding behavior in the Japanese stock market

    International Nuclear Information System (INIS)

    Cajueiro, Daniel O.; Tabak, Benjamin M.

    2009-01-01

    In this paper we present evidence of multifractality and herding behavior for a large set of Japanese stocks traded in the Tokyo Stock Exchange. We find evidence that herding behavior occurs in periods of extreme market movements. Therefore, based on the intuition behind the tests to detect herding phenomenon developed, for instance, in Christie and Huang [Christie W, Huang R. Following the pied pier: do individual returns herd around the market? Financ Analysts J 1995;51:31-7] and Chang et al. [Chang EC, Cheng JW, Khorana A. Examination of herd behavior in equity markets: an international perspective. J Bank Finance 2000;24:1651-99], we suggest that herding behavior may be one of the causes of multifractality.

  7. Lactation performance of Holstein cows treated with 2 formulations of recombinant bovine somatotropin in a large commercial dairy herd in Brazil.

    Science.gov (United States)

    de Morais, J P G; da S Cruz, A P; Minami, N S; Veronese, L P; Del Valle, T A; Aramini, J

    2017-07-01

    The objectives of this controlled study were to compare the effects of 2 different formulations of recombinant bovine somatotropin (rbST) on milk yield, milk composition (fat and protein), milk somatic cell count, and body condition score (BCS) among dairy cattle in a large commercial herd. Regulatory approved 500-mg zinc sesame oil base rbST (ZSO-rbST; Elanco Animal Health, Greenfield, IN) and vitamin E lecithin base rbST (VEL-rbST; LG Life Sciences, Seoul, South Korea) formulations were administered per the manufacturers' recommendations every 14 d over 17 injection cycles starting at 57 to 70 d of lactation (90 cows per rbST group). Control cows (n = 60) received no rbST. Somatotropin-treated animals (VEL-rbST and ZSO-rbST combined) had increased average milk yield and protein percentage and lower average BCS compared with control cows. For primiparous cows, average milk yield was 37.75 kg/d with the ZSO-rbST treatment and 35.72 kg/d with the VEL-rbST treatment. For multiparous cows, average milk yield was 40.13 kg/d with the ZSO-rbST treatment and 38.81 kg/d with the VEL-rbST treatment. There were no differences in milk fat percentage between VEL-rbST and ZSO-rbST treatments, but milk protein content was greater with VEL-rbST treatment than with ZSO-rbST treatment. Nonetheless, cows treated with ZSO-rbST yielded more kilograms of fat and protein per day than cows treated with VEL-rbST. No significant differences in BCS were found between both rbST treatment groups. The differential increase in milk yield between cows treated with ZSO-rbST and VEL-rbST was driven by rbST response differences both within the 14-d cycle and throughout the 17 injection cycles. The cows treated with VEL-rbST demonstrated a more variable 14-d milk yield response curve, with more pronounced valleys between injections compared with the ZSO-rbST formulation. In addition, only the ZSO-rbST treatment was effective in modifying the lactation persistency compared with control cows. Compared

  8. Dairy Herd Management Types Assessed from Indicators of Health, Reproduction, Replacement Milk Production

    DEFF Research Database (Denmark)

    Enevoldsen, Carsten; Hindhede, Jens; Kristensen, T.

    1996-01-01

    Variables related to health, reproduction, replacement milk production in 111 Danish dairy herds were studied with factor analysis. The objectives were to identify management types and to assess the relevance of those types for herd milk production. Median herd size and total milk production were...... 59 cows and 7100 kg of energy-corrected milk, respectively. Based on cow data, 22 herd variables were defined. A factor analysis identified 10 first-order factors and 5 second-order factors. The latter factors were valid indicators of replacement intensity, variability of milk production, potential...... for peak milk production, disease a complex pattern related to herd size and age, cow size live cattle sales. The potential for peak milk production, replacement intensity variability of milk production were strong predictors of herd milk production. Interactions with herd size were important. The derived...

  9. Factors associated with the occurrence of MRSA CC398 in herds of fattening pigs in Germany

    Directory of Open Access Journals (Sweden)

    Alt Katja

    2011-11-01

    Full Text Available Abstract Background The purpose of this study was to investigate the prevalence of MRSA in herds of fattening pigs in different regions of Germany, and to determine factors associated with the occurrence of this pathogen. For this purpose pooled dust samples were collected, and a questionnaire covered information regarding herd characteristics and management practices. Samples were pre-enriched in high-salt medium followed by selective enrichment containing cefoxitin/aztreonam, and culturing. Presumptive colonies were confirmed by multiplex-PCR targeting nuc-, mecA- and 16S rRNA-genes. Isolates were spa- and SCCmec-, and in selected cases, multilocus sequence-typed. Susceptibilities to 13 antimicrobials were determined by broth microdilution. Statistical analysis was carried out using backward stepwise logistic regression to calculate odds ratios with the MRSA test result as the outcome and herd characteristics as categorical covariates. Results Overall, 152 of 290 (52% fattening pig farms tested positive for MRSA. The prevalence in the east, north- and south-west of Germany ranged from 39 to 59%. t011 (66% and t034 (23% were the most commonly identified spa-types, and 85% of isolates carried SCCmec Type V. Identified spa-types were all associated with clonal complex CC398. Susceptibility testing revealed that all isolates were resistant to tetracycline. High resistance rates were also found for sulfamethoxazole/trimethoprim (40%, and quinupristin/dalfopristin (32%. In addition, 83% of strains displayed multidrug resistant (> 3 substance classes phenotypes. Logistic regression revealed herd size (large farms OR: 5.4; CI: 2.7-11.2; p Conclusions MRSA CC398 is widely distributed among herds of fattening pigs in Germany. Farm management plays a crucial role in the dissemination of MRSA with herd size, and production type representing potential major indicators.

  10. Factors associated with the occurrence of MRSA CC398 in herds of fattening pigs in Germany.

    Science.gov (United States)

    Alt, Katja; Fetsch, Alexandra; Schroeter, Andreas; Guerra, Beatriz; Hammerl, Jens A; Hertwig, Stefan; Senkov, Natalja; Geinets, Anna; Mueller-Graf, Christine; Braeunig, Juliane; Kaesbohrer, Annemarie; Appel, Bernd; Hensel, Andreas; Tenhagen, Bernd-Alois

    2011-11-10

    The purpose of this study was to investigate the prevalence of MRSA in herds of fattening pigs in different regions of Germany, and to determine factors associated with the occurrence of this pathogen. For this purpose pooled dust samples were collected, and a questionnaire covered information regarding herd characteristics and management practices. Samples were pre-enriched in high-salt medium followed by selective enrichment containing cefoxitin/aztreonam, and culturing. Presumptive colonies were confirmed by multiplex-PCR targeting nuc-, mecA- and 16S rRNA-genes. Isolates were spa- and SCCmec-, and in selected cases, multilocus sequence-typed. Susceptibilities to 13 antimicrobials were determined by broth microdilution. Statistical analysis was carried out using backward stepwise logistic regression to calculate odds ratios with the MRSA test result as the outcome and herd characteristics as categorical covariates. Overall, 152 of 290 (52%) fattening pig farms tested positive for MRSA. The prevalence in the east, north- and south-west of Germany ranged from 39 to 59%.t011 (66%) and t034 (23%) were the most commonly identified spa-types, and 85% of isolates carried SCCmec Type V. Identified spa-types were all associated with clonal complex CC398. Susceptibility testing revealed that all isolates were resistant to tetracycline. High resistance rates were also found for sulfamethoxazole/trimethoprim (40%), and quinupristin/dalfopristin (32%). In addition, 83% of strains displayed multidrug resistant (> 3 substance classes) phenotypes.Logistic regression revealed herd size (large farms OR: 5.4; CI: 2.7-11.2; p pig operations. MRSA CC398 is widely distributed among herds of fattening pigs in Germany. Farm management plays a crucial role in the dissemination of MRSA with herd size, and production type representing potential major indicators.

  11. Visual exposure to large and small portion sizes and perceptions of portion size normality: Three experimental studies.

    Science.gov (United States)

    Robinson, Eric; Oldham, Melissa; Cuckson, Imogen; Brunstrom, Jeffrey M; Rogers, Peter J; Hardman, Charlotte A

    2016-03-01

    Portion sizes of many foods have increased in recent times. In three studies we examined the effect that repeated visual exposure to larger versus smaller food portion sizes has on perceptions of what constitutes a normal-sized food portion and measures of portion size selection. In studies 1 and 2 participants were visually exposed to images of large or small portions of spaghetti bolognese, before making evaluations about an image of an intermediate sized portion of the same food. In study 3 participants were exposed to images of large or small portions of a snack food before selecting a portion size of snack food to consume. Across the three studies, visual exposure to larger as opposed to smaller portion sizes resulted in participants considering a normal portion of food to be larger than a reference intermediate sized portion. In studies 1 and 2 visual exposure to larger portion sizes also increased the size of self-reported ideal meal size. In study 3 visual exposure to larger portion sizes of a snack food did not affect how much of that food participants subsequently served themselves and ate. Visual exposure to larger portion sizes may adjust visual perceptions of what constitutes a 'normal' sized portion. However, we did not find evidence that visual exposure to larger portions altered snack food intake. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Some herding, record keeping and treatment methods used in Alaskan reindeer herds

    Directory of Open Access Journals (Sweden)

    Robert A. Dieterich

    1986-06-01

    Full Text Available Approximately 20000 reindeer (Rangifer tarandus in Alaska are gathered once or twice yearly to facilitate identification, serologic sampling, treatment and antler removal. Various air and land craft are used to bring the animals into a corral system from which they can be herded into a padded, pneumatically operated, squeeze apparatus. Ear tags are applied or read if already in place and ears are notched. A portable, computerized rapid data retrieval system is used to record reproductive success, vaccination and treatment status and other miscellaneous information. Ivermectin is being administered in the early winter months to treat reindeer in many herds for warbles, nasal bots and internal parasites. A killed, homologous Brucella suis type 4 vaccine is being used in two large (3500 herds. Efforts are being made to incorporate other innovative methods to improve herding and corralling methods.

  13. Embrittlement and decrease of apparent strength in large-sized ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    In fact, the dimensional disparity between tensile stress σ([F][L]. −2) and ..... they work only in a limited range. This is the case of the ...... ACI 1992 American Concrete Institute: Building Code 318R-89 (Detroit: ACI Press). Ba˘zant Z P 1984 Size ...

  14. Herd-level prevalence and associated risk factors for Toxoplasma gondii, Neospora caninum, Chlamydia abortus and bovine viral diarrhoea virus in commercial dairy and beef cattle in eastern, northern and northeastern China.

    Science.gov (United States)

    Sun, Wu-Wen; Meng, Qing-Feng; Cong, Wei; Shan, Xiao-Feng; Wang, Chun-Feng; Qian, Ai-Dong

    2015-11-01

    Although the seroprevalence of Toxoplasma gondii, Neospora caninum, Chlamydia abortus and bovine viral diarrhea virus infection in cattle have been reported in some areas in China, most of them were conducted with small number of cattle samples and very limited districts and neglected the assessment of herd management factors associated with herd-level prevalence of these pathogen infections. Thus, from September 2013 to December 2014, a large-scale seroprevalence study was conducted to determine the animal-level and herd-level seroprevalence and identify herd-level risk factors associated with these pathogen infections in 4487 cattle from 134 herds in five provinces (Heilongjiang, Jilin, Liaoning, Shandong, Hebei) and Inner Mongolia Autonomous Region of China. At animal level, the true prevalence of antibodies against T. gondii, N. caninum, C. abortus and bovine viral diarrhoea virus (BVDV) was 10.48, 17.14, 11.92 and 50.10%, respectively. At herd level, the true prevalence of antibodies against T. gondii, N. caninum, C. abortus and BVDV was 27.16, 29.10, 37.31 and 40.30%, respectively. Multivariate analysis of these characteristics showed that source of water and presence of felids were significantly associated with T. gondii infection in the studied cattle herds. Source of water was significantly associated with N. caninum infection in the studied cattle herds. While herd size and management system were significantly associated with BVDV infection in the studied cattle herds, this is the first report of herd-level prevalence and associated risk factors of T. gondii, N. caninum, C. abortus and BVDV infection in cattle in China.

  15. Size matters: large objects capture attention in visual search.

    Science.gov (United States)

    Proulx, Michael J

    2010-12-23

    Can objects or events ever capture one's attention in a purely stimulus-driven manner? A recent review of the literature set out the criteria required to find stimulus-driven attentional capture independent of goal-directed influences, and concluded that no published study has satisfied that criteria. Here visual search experiments assessed whether an irrelevantly large object can capture attention. Capture of attention by this static visual feature was found. The results suggest that a large object can indeed capture attention in a stimulus-driven manner and independent of displaywide features of the task that might encourage a goal-directed bias for large items. It is concluded that these results are either consistent with the stimulus-driven criteria published previously or alternatively consistent with a flexible, goal-directed mechanism of saliency detection.

  16. Aerodynamic Limits on Large Civil Tiltrotor Sizing and Efficiency

    Science.gov (United States)

    Acree, C W.

    2014-01-01

    The NASA Large Civil Tiltrotor (2nd generation, or LCTR2) is a useful reference design for technology impact studies. The present paper takes a broad view of technology assessment by examining the extremes of what aerodynamic improvements might hope to accomplish. Performance was analyzed with aerodynamically idealized rotor, wing, and airframe, representing the physical limits of a large tiltrotor. The analysis was repeated with more realistic assumptions, which revealed that increased maximum rotor lift capability is potentially more effective in improving overall vehicle efficiency than higher rotor or wing efficiency. To balance these purely theoretical studies, some practical limitations on airframe layout are also discussed, along with their implications for wing design. Performance of a less efficient but more practical aircraft with non-tilting nacelles is presented.

  17. Development of large size NC trepanning and horning machine

    International Nuclear Information System (INIS)

    Wada, Yoshiei; Aono, Fumiaki; Siga, Toshihiko; Sudo, Eiichi; Takasa, Seiju; Fukuyama, Masaaki; Sibukawa, Koichi; Nakagawa, Hirokatu

    2010-01-01

    Due to the recent increase in world energy demand, construction of considerable number of nuclear and fossil power plant has been proceeded and is further planned. High generating capacity plant requires large forged components such as monoblock turbine rotor shafts and the dimensions of them tend to increase. Some of these components have center bore for material test, NDE and other use. In order to cope with the increase in production of these large forgings with center bores, a new trepanning machine, which exclusively bore a deep hole, was developed in JSW taking account of many accumulated experiences and know-how of experts. The machine is the world largest 400t trepanning and horning machine with numerical control and has many advantage in safety, the machining precision, machining efficiency, operability, labor-saving, and energy saving. Furthermore, transfer of the technical skill became easy through concentrated monitoring system based on numerically analysed experts' know-how. (author)

  18. Remote aerosol testing of large size HEPA filter banks

    International Nuclear Information System (INIS)

    Franklin, B.; Pasha, M.; Bronger, C.A.

    1987-01-01

    Different methods of testing HEPA filter banks are described. Difficulties in remote testing of large banks of HEPA filters in series with minimum distances between banks, and with no available access upstream and downstream of the filter house, are discussed. Modifications incorporated to make the filter system suitable for remote testing without personnel re-entry into the filter house are described for a 51,000 m/sup 3//hr filter unit at the WIPP site

  19. Online Anti-Brand Herds

    DEFF Research Database (Denmark)

    Langley, David J.; Tan, Chee-Wee; Worm, Daniël

    The online environment offers a fertile breeding ground for anti-brand herds of disgruntled consumers. Firms are often caught off guard by the unpredictability of such herds and, as a consequence, are forced into a reactive, defensive stance. We conduct a social media analysis that aims to shed...... light on the formation, growth, and dissolution of online anti-brand herds. First we expand on the concept of environmental turbulence to advance core properties unique to online herd behavior. Next, based on evidence gathered from 40 online anti-brand herd episodes targeting two prominent firms from...... the Netherlands, we develop an analytical model to investigate drivers of herd formation, growth, and dissolution. Finally, combining environmental turbulence literature with our empirical findings, we derive a novel typology of online anti-brand herd behaviors, and put forward six propositions to guide theory...

  20. Cubicle Refusal in Norwegian Dairy Herds

    Directory of Open Access Journals (Sweden)

    Myren HJ

    2001-03-01

    Full Text Available In order to survey the behaviour of choosing the alley area instead of a cubicle as a lying place (cubicle refusal, a questionnaire was sent to the 273 dairy farms in Norway known to keep cows in cubicle housing systems. Sixty-six percent of the farmers contacted were included in the study. The median herd size was 18 cows (range 7–118. More than 85% of the herds had sheds providing one or more cubicles per cow. The mean herd occurrence of cubicle refusal was 6%, but showed great variation (range 0–55%. Regression analysis showed a significant association between rearing heifers in slatted floor pens and an increased cubicle refusal occurrence (p = 0.02, R2 = 0.05, while herd size, use of litter, or cubicle-to-animal ratio were not found to be associated with cubicle refusal. The practice of rearing heifers in slatted floor pens accounted for about one half of the observed cubicle refusal (etiologic fraction = 0.51.

  1. The large size straw drift chambers of the COMPASS experiment

    CERN Document Server

    Bychkov, V N; Dünnweber, W; Faessler, Martin A; Fischer, H; Franz, J; Geyer, R; Gousakov, Yu V; Grünemaier, A; Heinsius, F H; Ilgner, C; Ivanchenko, I M; Kekelidze, G D; Königsmann, K C; Livinski, V V; Lysan, V M; Marzec, J; Matveev, D A; Mishin, S V; Mialkovski, V V; Novikov, E A; Peshekhonov, V D; Platzer, K; San, M; Schmid, T; Shokin, V I; Sissakian, A N; Viriasov, K S; Wiedner, U; Zaremba, K; Zhukov, I A; Zlobin, Y L; Zvyagin, A

    2005-01-01

    Straw drift chambers are used for the Large Area Tracking (LAT) of the Common Muon and Proton Apparatus for Structure and Spectroscopy (COMPASS) at CERN. An active area of 130 m2 in total is covered by 12 440 straw tubes, which are arranged in 15 double layers. The design has been optimized with respect to spatial resolution, rate capability, low material budget and compactness of the detectors. Mechanical and electrical design considerations of the chambers are discussed as well as new production techniques. The mechanical precision of the chambers has been determined using a CCD X-ray scanning apparatus. Results about the performance during data taking in COMPASS are described.

  2. High female mortality resulting in herd collapse in free-ranging domesticated reindeer (Rangifer tarandus tarandus in Sweden.

    Directory of Open Access Journals (Sweden)

    Birgitta Åhman

    Full Text Available Reindeer herding in Sweden is a form of pastoralism practised by the indigenous Sámi population. The economy is mainly based on meat production. Herd size is generally regulated by harvest in order not to overuse grazing ranges and keep a productive herd. Nonetheless, herd growth and room for harvest is currently small in many areas. Negative herd growth and low harvest rate were observed in one of two herds in a reindeer herding community in Central Sweden. The herds (A and B used the same ranges from April until the autumn gathering in October-December, but were separated on different ranges over winter. Analyses of capture-recapture for 723 adult female reindeer over five years (2007-2012 revealed high annual losses (7.1% and 18.4%, for herd A and B respectively. A continuing decline in the total reindeer number in herd B demonstrated an inability to maintain the herd size in spite of a very small harvest. An estimated breakpoint for when herd size cannot be kept stable confirmed that the observed female mortality rate in herd B represented a state of herd collapse. Lower calving success in herd B compared to A indicated differences in winter foraging conditions. However, we found only minor differences in animal body condition between the herds in autumn. We found no evidence that a lower autumn body mass generally increased the risk for a female of dying from one autumn to the next. We conclude that the prime driver of the on-going collapse of herd B is not high animal density or poor body condition. Accidents or disease seem unlikely as major causes of mortality. Predation, primarily by lynx and wolverine, appears to be the most plausible reason for the high female mortality and state of collapse in the studied reindeer herding community.

  3. Small size modular fast reactors in large scale nuclear power

    International Nuclear Information System (INIS)

    Zrodnikov, A.V.; Toshinsky, G.I.; Komlev, O.G.; Dragunov, U.G.; Stepanov, V.S.; Klimov, N.N.; Kopytov, I.I.; Krushelnitsky, V.N.

    2005-01-01

    The report presents an innovative nuclear power technology (NPT) based on usage of modular type fast reactors (FR) (SVBR-75/100) with heavy liquid metal coolant (HLMC) i. e. eutectic lead-bismuth alloy mastered for Russian nuclear submarines' (NS) reactors. Use of this NPT makes it possible to eliminate a conflict between safety and economic requirements peculiar to the traditional reactors. Physical features of FRs, an integral design of the reactor and its small power (100 MWe), as well as natural properties of lead-bismuth coolant assured realization of the inherent safety properties. This made it possible to eliminate a lot of safety systems necessary for the reactor installations (RI) of operating NPPs and to design the modular NPP which technical and economical parameters are competitive not only with those of the NPP based on light water reactors (LWR) but with those of the steam-gas electric power plant. Multipurpose usage of transportable reactor modules SVBR-75/100 of entirely factory manufacture assures their production in large quantities that reduces their fabrication costs. The proposed NPT provides economically expedient change over to the closed nuclear fuel cycle (NFC). When the uranium-plutonium fuel is used, the breeding ratio is over one. Use of proposed NPT makes it possible to considerably increase the investment attractiveness of nuclear power (NP) with fast neutron reactors even today at low costs of natural uranium. (authors)

  4. Patterns of stillbirth and dystocia in Ontario cow-calf herds.

    Science.gov (United States)

    McDermott, J J; Allen, O B; Martin, S W; Alves, D M

    1992-01-01

    The association between a number of individual animal and herd level factors and calving problems in beef cows and heifers were examined. Data were from the 1987 calving season for a subset of 123 herds which maintained individual-animal records, from a sample of 180 randomly selected Ontario cow-calf herds. The median herd dystocia rate was 5.8% and 24.4% of herds had no dystocias. The median herd stillbirth rate was 2.8%, and 33.3% of herds had no stillbirths. Dystocias and stillbirths were much more common in heifers than in cows. Separate statistical models of dystocia and stillbirth for cows and heifers were created. Dystocia in cows was associated with calf sex, previous calving assistance and large breed type and birth weight. Variations in 1987 cow herd dystocia rates were associated with calving season, location and density, and the herd dystocia rate in 1986. Dystocia in heifers was associated with large breed type and calf birth weight. Herd-level management practices associated with increased heifer dystocia rates included breeding heifers to calve earlier than cows and rearing heifers together with the cow herd. Stillbirths for both cows and heifers were associated with calving assistance, particularly hard assistance. Herd-level management and other factors were unassociated with stillbirths. PMID:1586893

  5. Large size self-assembled quantum rings: quantum size effect and modulation on the surface diffusion.

    Science.gov (United States)

    Tong, Cunzhu; Yoon, Soon Fatt; Wang, Lijun

    2012-09-24

    We demonstrate experimentally the submicron size self-assembled (SA) GaAs quantum rings (QRs) by quantum size effect (QSE). An ultrathin In0.1 Ga0.9As layer with different thickness is deposited on the GaAs to modulate the surface nucleus diffusion barrier, and then the SA QRs are grown. It is found that the density of QRs is affected significantly by the thickness of inserted In0.1 Ga0.9As, and the diffusion barrier modulation reflects mainly on the first five monolayer . The physical mechanism behind is discussed. The further analysis shows that about 160 meV decrease in diffusion barrier can be achieved, which allows the SA QRs with density of as low as one QR per 6 μm2. Finally, the QRs with diameters of 438 nm and outer diameters of 736 nm are fabricated using QSE.

  6. Modeling the lowest-cost splitting of a herd of cows by optimizing a cost function

    Science.gov (United States)

    Gajamannage, Kelum; Bollt, Erik M.; Porter, Mason A.; Dawkins, Marian S.

    2017-06-01

    Animals live in groups to defend against predation and to obtain food. However, for some animals—especially ones that spend long periods of time feeding—there are costs if a group chooses to move on before their nutritional needs are satisfied. If the conflict between feeding and keeping up with a group becomes too large, it may be advantageous for some groups of animals to split into subgroups with similar nutritional needs. We model the costs and benefits of splitting in a herd of cows using a cost function that quantifies individual variation in hunger, desire to lie down, and predation risk. We model the costs associated with hunger and lying desire as the standard deviations of individuals within a group, and we model predation risk as an inverse exponential function of the group size. We minimize the cost function over all plausible groups that can arise from a given herd and study the dynamics of group splitting. We examine how the cow dynamics and cost function depend on the parameters in the model and consider two biologically-motivated examples: (1) group switching and group fission in a herd of relatively homogeneous cows, and (2) a herd with an equal number of adult males (larger animals) and adult females (smaller animals).

  7. A simulation model to quantify the value of implementing whole-herd Bovine viral diarrhea virus testing strategies in beef cow-calf herds.

    Science.gov (United States)

    Nickell, Jason S; White, Brad J; Larson, Robert L; Renter, David G; Sanderson, Mike W

    2011-03-01

    Although numerous diagnostic tests are available to identify cattle persistently infected (PI) with Bovine viral diarrhea virus (BVDV) in cow-calf herds, data are sparse when evaluating the economic viability of individual tests or diagnostic strategies. Multiple factors influence BVDV testing in determining if testing should be performed and which strategy to use. A stochastic model was constructed to estimate the value of implementing various whole-herd BVDV cow-calf testing protocols. Three common BVDV tests (immunohistochemistry, antigen-capture enzyme-linked immunosorbent assay, and polymerase chain reaction) performed on skin tissue were evaluated as single- or two-test strategies. The estimated testing value was calculated for each strategy at 3 herd sizes that reflect typical farm sizes in the United States (50, 100, and 500 cows) and 3 probabilities of BVDV-positive herd status (0.077, 0.19, 0.47) based upon the literature. The economic value of testing was the difference in estimated gross revenue between simulated cow-calf herds that either did or did not apply the specific testing strategy. Beneficial economic outcomes were more frequently observed when the probability of a herd being BVDV positive was 0.47. Although the relative value ranking of many testing strategies varied by each scenario, the two-test strategy composed of immunohistochemistry had the highest estimated value in all but one herd size-herd prevalence permutation. These data indicate that the estimated value of applying BVDV whole-herd testing strategies is influenced by the selected strategy, herd size, and the probability of herd BVDV-positive status; therefore, these factors should be considered when designing optimum testing strategies for cow-calf herds.

  8. Vaccination, herd behavior, and herd immunity.

    Science.gov (United States)

    Cohen, Matan J; Brezis, Mayer; Block, Colin; Diederich, Adele; Chinitz, David

    2013-11-01

    During the 2009 outbreak of novel influenza AH1N1, insufficient data were available to adequately inform decision makers about benefits and risks of vaccination and disease. We hypothesized that individuals would opt to mimic their peers, having no better decision anchor. We used Game Theory, decision analysis, and transmission models to simulate the impact of subjective risks and preference estimates on vaccination behavior. We asked 95 students to provide estimates of risk and health state valuations with regard to AH1N1 infection, complications, and expectations of vaccine benefits and risks. These estimates were included in a sequential chain of models: a dynamic epidemic model, a decision tree, and a population-level model. Additionally, participants' intentions to vaccinate or not at varying vaccination rates were documented. The model showed that at low vaccination rates, vaccination dominated. When vaccination rates increased above 78%, nonvaccination was the dominant strategy. We found that vaccination intentions did not correspond to the shift in strategy dominance and segregated to 3 types of intentions: regardless of what others do 29/95 (31%) intended to vaccinate while 27/95 (28%) did not; among 39 of 95 (41%) intention was positively associated with putative vaccination rates. Some people conform to the majority's choice, either shifting epidemic dynamics toward herd immunity or, conversely, limiting societal goals. Policy leaders should use models carefully, noting their limitations and theoretical assumptions. Behavior drivers were not explicitly explored in this study, and the discrepant results beg further investigation. Models including real subjective perceptions with empiric or subjective probabilities can provide insight into deviations from expected rational behavior and suggest interventions in order to provide better population outcomes.

  9. Breeding for reproduction traits in context of multiplication herds efficiency in swine

    Directory of Open Access Journals (Sweden)

    Petr Humpolíček

    2013-01-01

    Full Text Available Presented study is a follow-up to the studies focused on effect of different selection pressure applied on two subpopulations of purebred Czech Large White sows on performance in multiplication herds. Higher selection pressure particularly on litter size and number of function nipples, while lower pressure on growth performance was applied in one population. About 1214 farrows of 393 F1 Czech Large White sows were included into statistical evaluation. The mixed linear models using the procedure REML in SAS for Windows 9.1.2. was used. The hypothesis that progeny of sows from hyper-prolific subpopulation breed in multiplier herds have different performance was not confirmed which is in contrast to previous studies. This non-homogeneity can be related to non-additive genetic effects which are caused by crossbreeding while selection methods are based on additive models.

  10. The effect of grazing on cow mortality in Danish dairy herds

    DEFF Research Database (Denmark)

    Burow, Elke; Thomsen, Peter Thorup; Sørensen, Jan Tind

    2011-01-01

    The effect of summer grazing in large Danish dairy herds and certain management characteristics of grazing were studied for their impact on dairy cow mortality. Mortality data (from the Danish Cattle Database) from 391 Danish dairy herds (>100 cows) were combined with information from...... a questionnaire survey of grazing procedures on these herds in 2008. In all, 131 of the herds were identified as summer grazing and 260 as zero-grazing herds. The mortality was affected by an interaction of summer grazing and milking system. The risk of a cow dying was reduced to 46% in a grazing compared...... and pasture was associated with increased cow mortality....

  11. Defining the Pen Islands Caribou Herd of southern Hudson Bay

    Directory of Open Access Journals (Sweden)

    Kenneth F. Abraham

    1998-03-01

    Full Text Available In this paper, we describe the Pen Islands Herd of caribou, the largest aggregation of caribou in Ontario (it also occupies a portion of northeastern Manitoba. Photographic counts showed the herd had a minimum population of 2300 in 1979, 4660 in 1986, 7424 in 1987 and 10 798 in 1994. Throughout the 1980s, the Pen Islands caribou exhibited population behaviour similar to migratory barren-ground caribou herds, although morphology suggests they are woodland caribou or possibly a mixture of subspecies. The herd had well-defined traditional tundra calving grounds, formed nursery groups and large mobile post-calving aggregations, and migrated over 400 km between tundra summer habitats and boreal forest winter habitats. Its migration took it into three Canadian jurisdictions (Ontario, Manitoba, Northwest Territories and it was important to residents of both Manitoba and Ontario. It is clear that the herd should be managed as a migratory herd and the critical importance of both the coastal and variable large winter ranges should be noted in ensuring the herd's habitat needs are secure.

  12. Reproductive performance in a select sample of dairy herds.

    Science.gov (United States)

    Ferguson, James D; Skidmore, Andrew

    2013-02-01

    Sixteen herds were selected from a pool of 64 herds nominated by consultants for participation in a national survey to demonstrate excellence in reproductive performance. For inclusion in the survey, herds had to have comprehensive records in a farm computer database or participate in a Dairy Herd Improvement Association record system and have superior reproductive performance as judged by the herd advisor. Herd managers were asked to fill out a questionnaire to describe their reproductive management practices and provide herd records for data analysis. Reproductive analysis was based on individual cow records for active and cull dairy cows that calved during the calendar year 2010. Breeding records by cow were used to calculate indices for insemination rate (IR), conception rate (CR), pregnancy rate (PR), and culling. Herds ranged in size from 262 to 6,126 lactating and dry cows, with a mean of 1,654 [standard deviation (SD) 1,494] cows. Mean days to first insemination (DFS) was 71.2d (SD 4.7d), and IR for first insemination was 86.9%. Mean days between inseminations were 33.4d (SD 3.1d), and 15.4% of insemination intervals were greater than 48 d (range: 7.2 to 21.5%). First-service conception rate was 44.4% (SD 4.8%) across all herds and ranged from 37.5 to 51.8%. Mean PR was 32.0% (SD 3.9%) with a range of 26.5 to 39.4%. Lactation cull rate was 32.2% (SD 12.4%) with a range from 13.6 to 58.1%. Compared with mean data and SD for herds in the Raleigh Dairy Herd Improvement Association system, mean indices for these herds ranked them in the 99 th percentile for IR (using heat detection rate as comparison), 99 th percentile for PR, the bottom 18.6 percentile for DFS, and around the 50th percentile for CR. This suggests that excellent herd reproductive performance was associated with reproductive management that resulted in high insemination rates combined with average CR. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights

  13. Culling from the herd's perspective-Exploring herd-level management factors and culling rates in Québec dairy herds.

    Science.gov (United States)

    Haine, Denis; Delgado, Hector; Cue, Roger; Sewalem, Asheber; Wade, Kevin; Lacroix, René; Lefebvre, Daniel; Arsenault, Julie; Bouchard, Émile; Dubuc, Jocelyn

    2017-11-01

    , demonstrating the heterogeneity among herds for their demographics, reproduction and production performance, and health status. However, based on Principal Component Analysis (PCA), the profiles of herds could be determined according to specific, single, herd-level indicators independently. The relationships between culling rates and specific herd-level variables within factors were limited to livestock sales, proportion of first lactation cows, herd size, proportion of calvings occurring in the fall, longer calving intervals and reduced 21-day pregnancy rates, increased days to first service, average age at first calving, and reduced milk fever incidence. The indicators found could be considered as contextual variables in multilevel model-building strategies to investigate cow culling risk. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Ecological role of hunting in population dynamics and its implications for co-management of the Porcupine caribou herd

    Directory of Open Access Journals (Sweden)

    Thomas A. Hanley

    2000-04-01

    Full Text Available At a present population size of 160 000 animals, the Porcupine caribou herd has been subjected to an annual harvest rate of 2% for the past couple of decades. We modeled potential sensitivity of herd population dynamics to hunting and used that relation as a basis for a herd monitoring system. Maximum number of adult cows that could be harvested without causing a subsequent decline in herd size was calculated as a function of total number of adult cows in the herd and recruitment of calves to yearling age-class. Maximum cow harvest, therefore, is a threshold above which hunting has destabilizing effects on herd dynamics. Actual harvest in relation to theoretical maximum harvest provides a basis for prediction of herd sensitivity to hunting. Maximum harvest is a linear function of recruitment. Herd dynamics are especially sensitive to low recruitment, however, when combined with low herd size. The two relations involving recruitment and herd size provide the basis for predicting herd dynamics and sensitivity to hunting. Herd size is best estimated by aerial census, while an index of recruitment can be predicted by monitoring autumn body condition of adult females. Body condition can be estimated on the basis of a few simple metrics measured by hunters in the field. The hunters' data on body composition, combined with aerial census data on herd size, provide a useful tool for managers and co-management boards to devise policies and regulations to manage the herd. The population model and monitoring system can operate on the Internet and be accessible to all users in villages within the range of the Porcupine caribou herd.

  15. Large- and small-size advantages in sneaking behaviour in the dusky frillgoby Bathygobius fuscus

    OpenAIRE

    Takegaki, Takeshi; Kaneko, Takashi; Matsumoto, Yukio

    2012-01-01

    Sneaking tactic, a male alternative reproductive tactic involving sperm competition, is generally adopted by small individuals because of its inconspicuousness. However, large size has an advantage when competition occurs between sneakers for fertilization of eggs. Here, we suggest that both large- and small-size advantages of sneaker males are present within the same species. Large sneaker males of the dusky frillgoby Bathygobius fuscus showed a high success rate in intruding into spawning n...

  16. Herding Complex Networks

    KAUST Repository

    Ruf, Sebastian F.

    2018-04-12

    The problem of controlling complex networks is of interest to disciplines ranging from biology to swarm robotics. However, controllability can be too strict a condition, failing to capture a range of desirable behaviors. Herdability, which describes the ability to drive a system to a specific set in the state space, was recently introduced as an alternative network control notion. This paper considers the application of herdability to the study of complex networks. The herdability of a class of networked systems is investigated and two problems related to ensuring system herdability are explored. The first is the input addition problem, which investigates which nodes in a network should receive inputs to ensure that the system is herdable. The second is a related problem of selecting the best single node from which to herd the network, in the case that a single node is guaranteed to make the system is herdable. In order to select the best herding node, a novel control energy based herdability centrality measure is introduced.

  17. Improving the time efficiency of identifying dairy herds with poorer welfare in a population.

    Science.gov (United States)

    de Vries, M; Bokkers, E A M; van Schaik, G; Engel, B; Dijkstra, T; de Boer, I J M

    2016-10-01

    Animal-based welfare assessment is time consuming and expensive. A promising strategy for improving the efficiency of identifying dairy herds with poorer welfare is to first estimate levels of welfare in herds based on data that are more easily obtained. Our aims were to evaluate the potential of herd housing and management data for estimating the level of welfare in dairy herds, and to estimate the associated reduction in the number of farm visits required for identification of herds with poorer welfare in a population. Seven trained observers collected data on 6 animal-based welfare indicators in a selected sample of 181 loose-housed Dutch dairy herds (herd size: 22 to 211 cows). Severely lame cows, cows with lesions or swellings, cows with a dirty hindquarter, and very lean cows were counted, and avoidance distance was assessed for a sample of cows. Occurrence of displacements (social behavior) was recorded in the whole barn during 120 min of observation. For the same herds, data regarding cattle housing and management were collected on farms, and data relating to demography, management, milk production and composition, and fertility were extracted from national databases. A herd was classified as having poorer welfare when it belonged to the 25% worst-scoring herds. We used variables of herd housing and management data as potential predictors for individual animal-based welfare indicators in logistic regressions at the herd level. Prediction was less accurate for the avoidance distance index [area under the curve (AUC)=0.69], and moderately accurate for prevalence of severely lame cows (AUC=0.83), prevalence of cows with lesions or swellings (AUC=0.81), prevalence of cows with a dirty hindquarter (AUC=0.74), prevalence of very lean cows (AUC=0.83), and frequency of displacements (AUC=0.72). We compared the number of farm visits required for identifying herds with poorer welfare in a population for a risk-based screening with predictions based on herd housing

  18. Ecological role of hunting in population dynamics and its implications for co-management of the Porcupine caribou herd

    OpenAIRE

    Hanley, Thomas A.; Russell, Donald E.

    2000-01-01

    At a present population size of 160 000 animals, the Porcupine caribou herd has been subjected to an annual harvest rate of 2% for the past couple of decades. We modeled potential sensitivity of herd population dynamics to hunting and used that relation as a basis for a herd monitoring system. Maximum number of adult cows that could be harvested without causing a subsequent decline in herd size was calculated as a function of total number of adult cows in the herd and recruitment of calves to...

  19. Trends in slaughter pig production and antimicrobial consumption in Danish slaughter pig herds, 2002-2008

    DEFF Research Database (Denmark)

    Vieira, Antonio; Pires, Sara Monteiro; Houe, H.

    2011-01-01

    Overuse of antimicrobials in food-animal production is thought to be a major risk factor for the development of resistant bacterial populations. Data on non-human antimicrobial usage is essential for planning of intervention strategies to lower resistance levels at the country, region or herd...... levels. In this study we evaluated Danish national antimicrobial usage data for five antimicrobial classes used in slaughter pigs in different herd sizes and data on the number of slaughter pigs produced per herd, between 2002 and 2008, in Denmark. The objective was to ascertain...... if there is an association between herd size and amount of antimicrobials consumed. During this period, the overall number of herds with slaughter pigs decreased by 43%, with larger herds becoming more prevalent. The tetracycline treatment incidence (TI) rate increased from 0·28 to 0·70 animal-defined daily dose (ADD)/100...

  20. Large- and small-size advantages in sneaking behaviour in the dusky frillgoby Bathygobius fuscus

    Science.gov (United States)

    Takegaki, Takeshi; Kaneko, Takashi; Matsumoto, Yukio

    2012-04-01

    Sneaking tactic, a male alternative reproductive tactic involving sperm competition, is generally adopted by small individuals because of its inconspicuousness. However, large size has an advantage when competition occurs between sneakers for fertilization of eggs. Here, we suggest that both large- and small-size advantages of sneaker males are present within the same species. Large sneaker males of the dusky frillgoby Bathygobius fuscus showed a high success rate in intruding into spawning nests because of their advantage in competition among sneaker males in keeping a suitable position to sneak, whereas small sneakers had few chances to sneak. However, small sneaker males were able to stay in the nests longer than large sneaker males when they succeeded in sneak intrusion. This suggests the possibility of an increase in their paternity. The findings of these size-specific behavioural advantages may be important in considering the evolution of size-related reproductive traits.

  1. A questionnaire study of associations between potential risk factors and salmonella status in Swedish dairy herds.

    Science.gov (United States)

    Ågren, Estelle C C; Frössling, Jenny; Wahlström, Helene; Emanuelson, Ulf; Sternberg Lewerin, Susanna

    2017-08-01

    In this study associations between potential risk factors and salmonella status in Swedish dairy herds were investigated. A case-control study design was used, including existing as well as new cases. Herds were assigned a salmonella status on the basis of antibody analysis of bulk milk samples. Information on potential risk factors was collected from registry data and from farmers via a questionnaire. Univariable and multivariable logistic regression analyses were used to investigate associations between salmonella status and potential risk factors. In addition, multivariate analysis with Additive Bayesian Network (ABN) modelling was performed to improve understanding of the complex relationship between all the variables. Because of the difficulty in identifying associations between potential risk factors and infections with low prevalence and a large regional variation, exposure of potential risk factors in the high-prevalence region (Öland) were compared to exposure in other regions in Sweden. In total 483 of 996 (48%) farmers responded to the questionnaire, 69 herds had test-positive bulk milk samples. The strongest association with salmonella status was 'presence of salmonella test-positive herds pastures and providing protective clothing for visitors. The latter is probably a reflection of increased disease awareness in Öland. The ABN model showed associations between herd size and housing as well as several management procedures. This provides an explanation why herd size frequently has been identified as a risk factor for salmonella by other studies. The study confirms the importance of local transmission routes for salmonella, but does not identify specific components in this local spread. Therefore, it supports the use of a broad biosecurity approach in the prevention of salmonella. In Öland, some potential risk factors are more common than in other parts of Sweden. Theoretically these could contribute to the spread of salmonella, but this was not

  2. Small, medium, large or supersize? The development and evaluation of interventions targeted at portion size

    Science.gov (United States)

    Vermeer, W M; Steenhuis, I H M; Poelman, M P

    2014-01-01

    In the past decades, portion sizes of high-caloric foods and drinks have increased and can be considered an important environmental obesogenic factor. This paper describes a research project in which the feasibility and effectiveness of environmental interventions targeted at portion size was evaluated. The studies that we conducted revealed that portion size labeling, offering a larger variety of portion sizes, and proportional pricing (that is, a comparable price per unit regardless of the size) were considered feasible to implement according to both consumers and point-of-purchase representatives. Studies into the effectiveness of these interventions demonstrated that the impact of portion size labeling on the (intended) consumption of soft drinks was, at most, modest. Furthermore, the introduction of smaller portion sizes of hot meals in worksite cafeterias in addition to the existing size stimulated a moderate number of consumers to replace their large meals by a small meal. Elaborating on these findings, we advocate further research into communication and marketing strategies related to portion size interventions; the development of environmental portion size interventions as well as educational interventions that improve people's ability to deal with a ‘super-sized' environment; the implementation of regulation with respect to portion size labeling, and the use of nudges to stimulate consumers to select healthier portion sizes. PMID:25033959

  3. The welfare implications of large litter size in the domestic pig I

    DEFF Research Database (Denmark)

    Rutherford, K.M.D; Baxter, E.M.; D'Eath, R.B.

    2013-01-01

    Increasing litter size has long been a goal of pig breeders and producers, and may have implications for pig (Sus scrofa domesticus) welfare. This paper reviews the scientific evidence on biological factors affecting sow and piglet welfare in relation to large litter size. It is concluded that, i...

  4. Semi-empirical formula for large pore-size estimation from o-Ps annihilation lifetime

    International Nuclear Information System (INIS)

    Nguyen Duc Thanh; Tran Quoc Dung; Luu Anh Tuyen; Khuong Thanh Tuan

    2007-01-01

    The o-Ps annihilation rate in large pore was investigated by the semi-classical approach. The semi-empirical formula that simply correlates between the pore size and the o-Ps lifetime was proposed. The calculated results agree well with experiment in the range from some angstroms to several ten nanometers size of pore. (author)

  5. Fission gas release during post irradiation annealing of large grain size fuels from Hinkley point B

    International Nuclear Information System (INIS)

    Killeen, J.C.

    1997-01-01

    A series of post-irradiation anneals has been carried out on fuel taken from an experimental stringer from Hinkley Point B AGR. The stringer was part of an experimental programme in the reactor to study the effect of large grain size fuel. Three differing fuel types were present in separate pins in the stringer. One variant of large grain size fuel had been prepared by using an MgO dopant during fuel manufactured, a second by high temperature sintering of standard fuel and the third was a reference, 12μm grain size fuel. Both large grain size variants had similar grain sizes around 35μm. The present experiments took fuel samples from highly rated pins from the stringer with local burn-up in excess of 25GWd/tU and annealed these to temperature of up to 1535 deg. C under reducing conditions to allow a comparison of fission gas behaviour at high release levels. The results demonstrate the beneficial effect of large grain size on release rate of 85 Kr following interlinkage. At low temperatures and release rates there was no difference between the fuel types, but at temperatures in excess of 1400 deg. C the release rate was found to be inversely dependent on the fuel grain size. The experiments showed some differences between the doped and undoped large grains size fuel in that the former became interlinked at a lower temperature, releasing fission gas at an increased rate at this temperature. At higher temperatures the grain size effect was dominant. The temperature dependence for fission gas release was determined over a narrow range of temperature and found to be similar for all three types and for both pre-interlinkage and post-interlinkage releases, the difference between the release rates is then seen to be controlled by grain size. (author). 4 refs, 7 figs, 3 tabs

  6. Fission gas release during post irradiation annealing of large grain size fuels from Hinkley point B

    Energy Technology Data Exchange (ETDEWEB)

    Killeen, J C [Nuclear Electric plc, Barnwood (United Kingdom)

    1997-08-01

    A series of post-irradiation anneals has been carried out on fuel taken from an experimental stringer from Hinkley Point B AGR. The stringer was part of an experimental programme in the reactor to study the effect of large grain size fuel. Three differing fuel types were present in separate pins in the stringer. One variant of large grain size fuel had been prepared by using an MgO dopant during fuel manufactured, a second by high temperature sintering of standard fuel and the third was a reference, 12{mu}m grain size fuel. Both large grain size variants had similar grain sizes around 35{mu}m. The present experiments took fuel samples from highly rated pins from the stringer with local burn-up in excess of 25GWd/tU and annealed these to temperature of up to 1535 deg. C under reducing conditions to allow a comparison of fission gas behaviour at high release levels. The results demonstrate the beneficial effect of large grain size on release rate of {sup 85}Kr following interlinkage. At low temperatures and release rates there was no difference between the fuel types, but at temperatures in excess of 1400 deg. C the release rate was found to be inversely dependent on the fuel grain size. The experiments showed some differences between the doped and undoped large grains size fuel in that the former became interlinked at a lower temperature, releasing fission gas at an increased rate at this temperature. At higher temperatures the grain size effect was dominant. The temperature dependence for fission gas release was determined over a narrow range of temperature and found to be similar for all three types and for both pre-interlinkage and post-interlinkage releases, the difference between the release rates is then seen to be controlled by grain size. (author). 4 refs, 7 figs, 3 tabs.

  7. Cow- and herd-level risk factors for on-farm mortality in Midwest US dairy herds.

    Science.gov (United States)

    Shahid, M Q; Reneau, J K; Chester-Jones, H; Chebel, R C; Endres, M I

    2015-07-01

    The objectives of this study were to describe on-farm mortality and to investigate cow- and herd-level risk factors associated with on-farm mortality in Midwest US dairy herds using lactation survival analysis. We analyzed a total of approximately 5.9 million DHIA lactation records from 10 Midwest US states from January 2006 to December 2010. The cow-level independent variables used in the models were first test-day milk yield, milk fat percent, milk protein percent, fat-to-protein ratio, milk urea nitrogen, somatic cell score, previous dry period, previous calving interval, stillbirth, calf sex, twinning, calving difficulty, season of calving, parity, and breed. The herd-level variables included herd size, calving interval, somatic cell score, 305-d mature-equivalent milk yield, and herd stillbirth percentage. Descriptive analysis showed that overall cow-level mortality rate was 6.4 per 100 cow-years and it increased from 5.9 in 2006 to 6.8 in 2010. Mortality was the primary reason of leaving the herd (19.4% of total culls) followed by reproduction (14.6%), injuries and other (14.0%), low production (12.3%), and mastitis (10.5%). Risk factor analysis showed that increased hazard for mortality was associated with higher fat-to-protein ratio (>1.6 vs. 1 to 1.6), higher milk fat percent, lower milk protein percent, cows with male calves, cows carrying multiple calves, higher milk urea nitrogen, increasing parity, longer previous calving interval, higher first test-day somatic cell score, increased calving difficulty score, and breed (Holstein vs. others). Decreased hazard for mortality was associated with higher first test-day milk yield, higher milk protein, and shorter dry period. For herd-level factors, increased hazard for mortality was associated with increased herd size, increased percentage of stillbirths, higher somatic cell score, and increased herd calving interval. Cows in herds with higher milk yield had lower mortality hazard. Results of the study

  8. Age-structured dynamic, stochastic and mechanistic simulation model of Salmonella Dublin infection within dairy herds

    DEFF Research Database (Denmark)

    Nielsen, Liza Rosenbaum; Kudahl, Anne Braad; Østergaard, Søren

    2012-01-01

    for the individual animals in each of the six age groups in the herd. The hygiene level was highly influential on the probability that the infection spread within the herd, duration of infection and epidemic size. The herd susceptibility level was also influential, but not likely to provide sufficient prevention...... of the six age-groups; 2) S. Dublin incidence and number of animals in each infection state; and 3) S. Dublin related morbidity and mortality in the acutely infected animals. The effects of introducing one infectious heifer on the risk of spread of S. Dublin within the herd and on the duration of infection...... and control of infection on its own. Herd size did not affect the probability of infection spread upon exposure, but the larger the herd the more important were management and housing practices that improve hygiene and reduce susceptibility to shorten durations of infection in the herd and to increase...

  9. Interlayer catalytic exfoliation realizing scalable production of large-size pristine few-layer graphene

    OpenAIRE

    Geng, Xiumei; Guo, Yufen; Li, Dongfang; Li, Weiwei; Zhu, Chao; Wei, Xiangfei; Chen, Mingliang; Gao, Song; Qiu, Shengqiang; Gong, Youpin; Wu, Liqiong; Long, Mingsheng; Sun, Mengtao; Pan, Gebo; Liu, Liwei

    2013-01-01

    Mass production of reduced graphene oxide and graphene nanoplatelets has recently been achieved. However, a great challenge still remains in realizing large-quantity and high-quality production of large-size thin few-layer graphene (FLG). Here, we create a novel route to solve the issue by employing one-time-only interlayer catalytic exfoliation (ICE) of salt-intercalated graphite. The typical FLG with a large lateral size of tens of microns and a thickness less than 2?nm have been obtained b...

  10. Effect of grazing on the cow welfare of dairy herds evaluated by a multidimensional welfare index

    DEFF Research Database (Denmark)

    Burow, E.; Rousing, T.; Thomsen, P. T.

    2013-01-01

    Structural development in the prime sector has led to increasing herd sizes and new barn systems, followed by less summer grazing for dairy cows in Denmark. Effects of grazing on single welfare measures in dairy cows - for example, the presence of integument alterations or mortality - have been......) inspired multidimensional dairy cow welfare assessment protocol, the within-herd effect of summer grazing compared with winter barn housing in Danish dairy herds with cubicle free-stall systems for the lactating cows. Our hypothesis was that cow welfare in dairy herds was better during summer grazing than...... out to be more beneficial than few daily grazing hours (range average above 9 to 21 h) for the welfare of the dairy herds. In conclusion, this study reports a positive within-herd effect of summer grazing on dairy cow welfare, where many daily grazing hours were more beneficial than few daily grazing...

  11. Spin-torque oscillation in large size nano-magnet with perpendicular magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Linqiang, E-mail: LL6UK@virginia.edu [Department of Physics, University of Virginia, Charlottesville, VA 22904 (United States); Kabir, Mehdi [Department of Electrical & Computer Engineering, University of Virginia, Charlottesville, VA 22904 (United States); Dao, Nam; Kittiwatanakul, Salinporn [Department of Materials Science & Engineering, University of Virginia, Charlottesville, VA 22904 (United States); Cyberey, Michael [Department of Electrical Engineering, University of Virginia, Charlottesville, VA 22904 (United States); Wolf, Stuart A. [Department of Physics, University of Virginia, Charlottesville, VA 22904 (United States); Department of Materials Science & Engineering, University of Virginia, Charlottesville, VA 22904 (United States); Institute of Defense Analyses, Alexandria, VA 22311 (United States); Stan, Mircea [Department of Electrical & Computer Engineering, University of Virginia, Charlottesville, VA 22904 (United States); Lu, Jiwei [Department of Materials Science & Engineering, University of Virginia, Charlottesville, VA 22904 (United States)

    2017-06-15

    Highlights: • 500 nm size nano-pillar device was fabricated by photolithography techniques. • A magnetic hybrid structure was achieved with perpendicular magnetic fields. • Spin torque switching and oscillation was demonstrated in the large sized device. • Micromagnetic simulations accurately reproduced the experimental results. • Simulations demonstrated the synchronization of magnetic inhomogeneities. - Abstract: DC current induced magnetization reversal and magnetization oscillation was observed in 500 nm large size Co{sub 90}Fe{sub 10}/Cu/Ni{sub 80}Fe{sub 20} pillars. A perpendicular external field enhanced the coercive field separation between the reference layer (Co{sub 90}Fe{sub 10}) and free layer (Ni{sub 80}Fe{sub 20}) in the pseudo spin valve, allowing a large window of external magnetic field for exploring the free-layer reversal. A magnetic hybrid structure was achieved for the study of spin torque oscillation by applying a perpendicular field >3 kOe. The magnetization precession was manifested in terms of the multiple peaks on the differential resistance curves. Depending on the bias current and applied field, the regions of magnetic switching and magnetization precession on a dynamical stability diagram has been discussed in details. Micromagnetic simulations are shown to be in good agreement with experimental results and provide insight for synchronization of inhomogeneities in large sized device. The ability to manipulate spin-dynamics on large size devices could be proved useful for increasing the output power of the spin-transfer nano-oscillators (STNOs).

  12. Sero prevalence and risk factors associated with bovine herpes virus type 1 (BHV1) infection in non-vaccinated cattle herds in Andalusia (South of Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Garcia, M. A.; Arenas-Casas, A.; Carbonero-Martinez, A.; Borge-Rodriguez, C.; Garcia-Bocanegra, I.; Maldonado, J. L.; Gomez-Pacheco, J. M.; Perea-Remujo, J. A.

    2009-07-01

    An epidemiological and serological survey of bovine herpes virus 1 (BHV1) infection was conducted in Andalusia from January to April of 2000. A total of 4,035 blood samples were collected from 164 herds. A questionnaire, which included variables potentially associated with infection, was filled out for each herd. Serum samples were obtained to identify specific BHV1 antibodies and were tested using a blocking ELISA test. The observed crude odds ratio (OR) (estimate of the chance of a particular event occurring in an exposed group in relation to its rate of occurrence in a nonexposed group) for vaccination is 9.8 (95 % confidence interval: 8.3-11.7). The vaccinated group comprised large dairy farms. This study can only be considered as representative of unvaccinated, small to medium size dairy farms and beef farms in Andalusia. True sero prevalence of the BHV1 virus in non vaccinated bovine populations in Andalusia reached 45.7% of individuals and 70.4% of herds. Risk factors for BHV1 infection in bovine Andalusian non vaccinated herds are nonexistence of specific cattle infrastructure (OR: 3.07), beef crossbreeding (OR: 7.90), affiliation with Livestock Health Defence Associations (OR: 2.57), a history of reproductive disorders (OR: 8.39), external replacement (OR: 2.74), proximity to an urban area (OR: 6.11) and herd size (41.98). To control for confounding effects, a binomial logistic regression model was developed. From this regression, BHV1 infections are concentrated in large herds, with external replacement, located close to urban areas. This is the first published report on BHV1 prevalence in the South of Spain. (Author) 14 refs.

  13. Damage threshold from large retinal spot size repetitive-pulse laser exposures.

    Science.gov (United States)

    Lund, Brian J; Lund, David J; Edsall, Peter R

    2014-10-01

    The retinal damage thresholds for large spot size, multiple-pulse exposures to a Q-switched, frequency doubled Nd:YAG laser (532 nm wavelength, 7 ns pulses) have been measured for 100 μm and 500 μm retinal irradiance diameters. The ED50, expressed as energy per pulse, varies only weakly with the number of pulses, n, for these extended spot sizes. The previously reported threshold for a multiple-pulse exposure for a 900 μm retinal spot size also shows the same weak dependence on the number of pulses. The multiple-pulse ED50 for an extended spot-size exposure does not follow the n dependence exhibited by small spot size exposures produced by a collimated beam. Curves derived by using probability-summation models provide a better fit to the data.

  14. Classification of large-sized hyperspectral imagery using fast machine learning algorithms

    Science.gov (United States)

    Xia, Junshi; Yokoya, Naoto; Iwasaki, Akira

    2017-07-01

    We present a framework of fast machine learning algorithms in the context of large-sized hyperspectral images classification from the theoretical to a practical viewpoint. In particular, we assess the performance of random forest (RF), rotation forest (RoF), and extreme learning machine (ELM) and the ensembles of RF and ELM. These classifiers are applied to two large-sized hyperspectral images and compared to the support vector machines. To give the quantitative analysis, we pay attention to comparing these methods when working with high input dimensions and a limited/sufficient training set. Moreover, other important issues such as the computational cost and robustness against the noise are also discussed.

  15. Genome size variation affects song attractiveness in grasshoppers: evidence for sexual selection against large genomes.

    Science.gov (United States)

    Schielzeth, Holger; Streitner, Corinna; Lampe, Ulrike; Franzke, Alexandra; Reinhold, Klaus

    2014-12-01

    Genome size is largely uncorrelated to organismal complexity and adaptive scenarios. Genetic drift as well as intragenomic conflict have been put forward to explain this observation. We here study the impact of genome size on sexual attractiveness in the bow-winged grasshopper Chorthippus biguttulus. Grasshoppers show particularly large variation in genome size due to the high prevalence of supernumerary chromosomes that are considered (mildly) selfish, as evidenced by non-Mendelian inheritance and fitness costs if present in high numbers. We ranked male grasshoppers by song characteristics that are known to affect female preferences in this species and scored genome sizes of attractive and unattractive individuals from the extremes of this distribution. We find that attractive singers have significantly smaller genomes, demonstrating that genome size is reflected in male courtship songs and that females prefer songs of males with small genomes. Such a genome size dependent mate preference effectively selects against selfish genetic elements that tend to increase genome size. The data therefore provide a novel example of how sexual selection can reinforce natural selection and can act as an agent in an intragenomic arms race. Furthermore, our findings indicate an underappreciated route of how choosy females could gain indirect benefits. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  16. Uncertainty budget in internal monostandard NAA for small and large size samples analysis

    International Nuclear Information System (INIS)

    Dasari, K.B.; Acharya, R.

    2014-01-01

    Total uncertainty budget evaluation on determined concentration value is important under quality assurance programme. Concentration calculation in NAA or carried out by relative NAA and k0 based internal monostandard NAA (IM-NAA) method. IM-NAA method has been used for small and large sample analysis of clay potteries. An attempt was made to identify the uncertainty components in IM-NAA and uncertainty budget for La in both small and large size samples has been evaluated and compared. (author)

  17. A Financial Market Model Incorporating Herd Behaviour.

    Science.gov (United States)

    Wray, Christopher M; Bishop, Steven R

    2016-01-01

    Herd behaviour in financial markets is a recurring phenomenon that exacerbates asset price volatility, and is considered a possible contributor to market fragility. While numerous studies investigate herd behaviour in financial markets, it is often considered without reference to the pricing of financial instruments or other market dynamics. Here, a trader interaction model based upon informational cascades in the presence of information thresholds is used to construct a new model of asset price returns that allows for both quiescent and herd-like regimes. Agent interaction is modelled using a stochastic pulse-coupled network, parametrised by information thresholds and a network coupling probability. Agents may possess either one or two information thresholds that, in each case, determine the number of distinct states an agent may occupy before trading takes place. In the case where agents possess two thresholds (labelled as the finite state-space model, corresponding to agents' accumulating information over a bounded state-space), and where coupling strength is maximal, an asymptotic expression for the cascade-size probability is derived and shown to follow a power law when a critical value of network coupling probability is attained. For a range of model parameters, a mixture of negative binomial distributions is used to approximate the cascade-size distribution. This approximation is subsequently used to express the volatility of model price returns in terms of the model parameter which controls the network coupling probability. In the case where agents possess a single pulse-coupling threshold (labelled as the semi-infinite state-space model corresponding to agents' accumulating information over an unbounded state-space), numerical evidence is presented that demonstrates volatility clustering and long-memory patterns in the volatility of asset returns. Finally, output from the model is compared to both the distribution of historical stock returns and the market

  18. A Financial Market Model Incorporating Herd Behaviour.

    Directory of Open Access Journals (Sweden)

    Christopher M Wray

    Full Text Available Herd behaviour in financial markets is a recurring phenomenon that exacerbates asset price volatility, and is considered a possible contributor to market fragility. While numerous studies investigate herd behaviour in financial markets, it is often considered without reference to the pricing of financial instruments or other market dynamics. Here, a trader interaction model based upon informational cascades in the presence of information thresholds is used to construct a new model of asset price returns that allows for both quiescent and herd-like regimes. Agent interaction is modelled using a stochastic pulse-coupled network, parametrised by information thresholds and a network coupling probability. Agents may possess either one or two information thresholds that, in each case, determine the number of distinct states an agent may occupy before trading takes place. In the case where agents possess two thresholds (labelled as the finite state-space model, corresponding to agents' accumulating information over a bounded state-space, and where coupling strength is maximal, an asymptotic expression for the cascade-size probability is derived and shown to follow a power law when a critical value of network coupling probability is attained. For a range of model parameters, a mixture of negative binomial distributions is used to approximate the cascade-size distribution. This approximation is subsequently used to express the volatility of model price returns in terms of the model parameter which controls the network coupling probability. In the case where agents possess a single pulse-coupling threshold (labelled as the semi-infinite state-space model corresponding to agents' accumulating information over an unbounded state-space, numerical evidence is presented that demonstrates volatility clustering and long-memory patterns in the volatility of asset returns. Finally, output from the model is compared to both the distribution of historical stock

  19. A Financial Market Model Incorporating Herd Behaviour

    Science.gov (United States)

    2016-01-01

    Herd behaviour in financial markets is a recurring phenomenon that exacerbates asset price volatility, and is considered a possible contributor to market fragility. While numerous studies investigate herd behaviour in financial markets, it is often considered without reference to the pricing of financial instruments or other market dynamics. Here, a trader interaction model based upon informational cascades in the presence of information thresholds is used to construct a new model of asset price returns that allows for both quiescent and herd-like regimes. Agent interaction is modelled using a stochastic pulse-coupled network, parametrised by information thresholds and a network coupling probability. Agents may possess either one or two information thresholds that, in each case, determine the number of distinct states an agent may occupy before trading takes place. In the case where agents possess two thresholds (labelled as the finite state-space model, corresponding to agents’ accumulating information over a bounded state-space), and where coupling strength is maximal, an asymptotic expression for the cascade-size probability is derived and shown to follow a power law when a critical value of network coupling probability is attained. For a range of model parameters, a mixture of negative binomial distributions is used to approximate the cascade-size distribution. This approximation is subsequently used to express the volatility of model price returns in terms of the model parameter which controls the network coupling probability. In the case where agents possess a single pulse-coupling threshold (labelled as the semi-infinite state-space model corresponding to agents’ accumulating information over an unbounded state-space), numerical evidence is presented that demonstrates volatility clustering and long-memory patterns in the volatility of asset returns. Finally, output from the model is compared to both the distribution of historical stock returns and the

  20. Comparison of silicon strip tracker module size using large sensors from 6 inch wafers

    CERN Multimedia

    Honma, Alan

    1999-01-01

    Two large silicon strip sensor made from 6 inch wafers are placed next to each other to simulate the size of a CMS outer silicon tracker module. On the left is a prototype 2 sensor CMS inner endcap silicon tracker module made from 4 inch wafers.

  1. Synthesis of mesoporous carbon nanoparticles with large and tunable pore sizes

    Science.gov (United States)

    Liu, Chao; Yu, Meihua; Li, Yang; Li, Jiansheng; Wang, Jing; Yu, Chengzhong; Wang, Lianjun

    2015-07-01

    Mesoporous carbon nanoparticles (MCNs) with large and adjustable pores have been synthesized by using poly(ethylene oxide)-b-polystyrene (PEO-b-PS) as a template and resorcinol-formaldehyde (RF) as a carbon precursor. The resulting MCNs possess small diameters (100-126 nm) and high BET surface areas (up to 646 m2 g-1). By using home-designed block copolymers, the pore size of MCNs can be tuned in the range of 13-32 nm. Importantly, the pore size of 32 nm is the largest among the MCNs prepared by the soft-templating route. The formation mechanism and structure evolution of MCNs were studied by TEM and DLS measurements, based on which a soft-templating/sphere packing mechanism was proposed. Because of the large pores and small particle sizes, the resulting MCNs were excellent nano-carriers to deliver biomolecules into cancer cells. MCNs were further demonstrated with negligible toxicity. It is anticipated that this carbon material with large pores and small particle sizes may have excellent potential in drug/gene delivery.Mesoporous carbon nanoparticles (MCNs) with large and adjustable pores have been synthesized by using poly(ethylene oxide)-b-polystyrene (PEO-b-PS) as a template and resorcinol-formaldehyde (RF) as a carbon precursor. The resulting MCNs possess small diameters (100-126 nm) and high BET surface areas (up to 646 m2 g-1). By using home-designed block copolymers, the pore size of MCNs can be tuned in the range of 13-32 nm. Importantly, the pore size of 32 nm is the largest among the MCNs prepared by the soft-templating route. The formation mechanism and structure evolution of MCNs were studied by TEM and DLS measurements, based on which a soft-templating/sphere packing mechanism was proposed. Because of the large pores and small particle sizes, the resulting MCNs were excellent nano-carriers to deliver biomolecules into cancer cells. MCNs were further demonstrated with negligible toxicity. It is anticipated that this carbon material with large pores and

  2. Large Time Asymptotics for a Continuous Coagulation-Fragmentation Model with Degenerate Size-Dependent Diffusion

    KAUST Repository

    Desvillettes, Laurent

    2010-01-01

    We study a continuous coagulation-fragmentation model with constant kernels for reacting polymers (see [M. Aizenman and T. Bak, Comm. Math. Phys., 65 (1979), pp. 203-230]). The polymers are set to diffuse within a smooth bounded one-dimensional domain with no-flux boundary conditions. In particular, we consider size-dependent diffusion coefficients, which may degenerate for small and large cluster-sizes. We prove that the entropy-entropy dissipation method applies directly in this inhomogeneous setting. We first show the necessary basic a priori estimates in dimension one, and second we show faster-than-polynomial convergence toward global equilibria for diffusion coefficients which vanish not faster than linearly for large sizes. This extends the previous results of [J.A. Carrillo, L. Desvillettes, and K. Fellner, Comm. Math. Phys., 278 (2008), pp. 433-451], which assumes that the diffusion coefficients are bounded below. © 2009 Society for Industrial and Applied Mathematics.

  3. Small-size pedestrian detection in large scene based on fast R-CNN

    Science.gov (United States)

    Wang, Shengke; Yang, Na; Duan, Lianghua; Liu, Lu; Dong, Junyu

    2018-04-01

    Pedestrian detection is a canonical sub-problem of object detection with high demand during recent years. Although recent deep learning object detectors such as Fast/Faster R-CNN have shown excellent performance for general object detection, they have limited success for small size pedestrian detection in large-view scene. We study that the insufficient resolution of feature maps lead to the unsatisfactory accuracy when handling small instances. In this paper, we investigate issues involving Fast R-CNN for pedestrian detection. Driven by the observations, we propose a very simple but effective baseline for pedestrian detection based on Fast R-CNN, employing the DPM detector to generate proposals for accuracy, and training a fast R-CNN style network to jointly optimize small size pedestrian detection with skip connection concatenating feature from different layers to solving coarseness of feature maps. And the accuracy is improved in our research for small size pedestrian detection in the real large scene.

  4. Validation Of Intermediate Large Sample Analysis (With Sizes Up to 100 G) and Associated Facility Improvement

    International Nuclear Information System (INIS)

    Bode, P.; Koster-Ammerlaan, M.J.J.

    2018-01-01

    Pragmatic rather than physical correction factors for neutron and gamma-ray shielding were studied for samples of intermediate size, i.e. up to the 10-100 gram range. It was found that for most biological and geological materials, the neutron self-shielding is less than 5 % and the gamma-ray self-attenuation can easily be estimated. A trueness control material of 1 kg size was made based on use of left-overs of materials, used in laboratory intercomparisons. A design study for a large sample pool-side facility, handling plate-type volumes, had to be stopped because of a reduction in human resources, available for this CRP. The large sample NAA facilities were made available to guest scientists from Greece and Brazil. The laboratory for neutron activation analysis participated in the world’s first laboratory intercomparison utilizing large samples. (author)

  5. Size Reduction Techniques for Large Scale Permanent Magnet Generators in Wind Turbines

    Science.gov (United States)

    Khazdozian, Helena; Hadimani, Ravi; Jiles, David

    2015-03-01

    Increased wind penetration is necessary to reduce U.S. dependence on fossil fuels, combat climate change and increase national energy security. The U.S Department of Energy has recommended large scale and offshore wind turbines to achieve 20% wind electricity generation by 2030. Currently, geared doubly-fed induction generators (DFIGs) are typically employed in the drivetrain for conversion of mechanical to electrical energy. Yet, gearboxes account for the greatest downtime of wind turbines, decreasing reliability and contributing to loss of profit. Direct drive permanent magnet generators (PMGs) offer a reliable alternative to DFIGs by eliminating the gearbox. However, PMGs scale up in size and weight much more rapidly than DFIGs as rated power is increased, presenting significant challenges for large scale wind turbine application. Thus, size reduction techniques are needed for viability of PMGs in large scale wind turbines. Two size reduction techniques are presented. It is demonstrated that 25% size reduction of a 10MW PMG is possible with a high remanence theoretical permanent magnet. Additionally, the use of a Halbach cylinder in an outer rotor PMG is investigated to focus magnetic flux over the rotor surface in order to increase torque. This work was supported by the National Science Foundation under Grant No. 1069283 and a Barbara and James Palmer Endowment at Iowa State University.

  6. Conflicts between reindeer herding and an expanding caribou herd in Alaska

    Directory of Open Access Journals (Sweden)

    Greg L. Finstad

    2002-04-01

    Full Text Available The reindeer industry has existed in Alaska since 1892. This industry has largely been concentrated on the Seward Peninsula, Alaska because suitable habitat has been available and caribou have been absent here for over 100 years. Until recently, reindeer meat and velvet antler production consistently generated millions of dollars in revenue critical to the economies of rural Alaskan communities. From 1976 to 1996 the Western Arctic Caribou Herd (WACH increased from about 75 000 to 463 000 animals. Concurrently, seasonal range use of the WACH shifted westward onto traditional reindeer ranges of the Seward Peninsula. Reindeer herders lost 75-100% of their herds through commingling and out¬migration with wild caribou. This loss of over 12 000 reindeer represents a potential economic value of 13 million dollars. Sustainable meat and velvet antler production and the economies of western Alaskan are likely to be affected by these changes.

  7. Evaluation of Kirkwood-Buff integrals via finite size scaling: a large scale molecular dynamics study

    Science.gov (United States)

    Dednam, W.; Botha, A. E.

    2015-01-01

    Solvation of bio-molecules in water is severely affected by the presence of co-solvent within the hydration shell of the solute structure. Furthermore, since solute molecules can range from small molecules, such as methane, to very large protein structures, it is imperative to understand the detailed structure-function relationship on the microscopic level. For example, it is useful know the conformational transitions that occur in protein structures. Although such an understanding can be obtained through large-scale molecular dynamic simulations, it is often the case that such simulations would require excessively large simulation times. In this context, Kirkwood-Buff theory, which connects the microscopic pair-wise molecular distributions to global thermodynamic properties, together with the recently developed technique, called finite size scaling, may provide a better method to reduce system sizes, and hence also the computational times. In this paper, we present molecular dynamics trial simulations of biologically relevant low-concentration solvents, solvated by aqueous co-solvent solutions. In particular we compare two different methods of calculating the relevant Kirkwood-Buff integrals. The first (traditional) method computes running integrals over the radial distribution functions, which must be obtained from large system-size NVT or NpT simulations. The second, newer method, employs finite size scaling to obtain the Kirkwood-Buff integrals directly by counting the particle number fluctuations in small, open sub-volumes embedded within a larger reservoir that can be well approximated by a much smaller simulation cell. In agreement with previous studies, which made a similar comparison for aqueous co-solvent solutions, without the additional solvent, we conclude that the finite size scaling method is also applicable to the present case, since it can produce computationally more efficient results which are equivalent to the more costly radial distribution

  8. Evaluation of Kirkwood-Buff integrals via finite size scaling: a large scale molecular dynamics study

    International Nuclear Information System (INIS)

    Dednam, W; Botha, A E

    2015-01-01

    Solvation of bio-molecules in water is severely affected by the presence of co-solvent within the hydration shell of the solute structure. Furthermore, since solute molecules can range from small molecules, such as methane, to very large protein structures, it is imperative to understand the detailed structure-function relationship on the microscopic level. For example, it is useful know the conformational transitions that occur in protein structures. Although such an understanding can be obtained through large-scale molecular dynamic simulations, it is often the case that such simulations would require excessively large simulation times. In this context, Kirkwood-Buff theory, which connects the microscopic pair-wise molecular distributions to global thermodynamic properties, together with the recently developed technique, called finite size scaling, may provide a better method to reduce system sizes, and hence also the computational times. In this paper, we present molecular dynamics trial simulations of biologically relevant low-concentration solvents, solvated by aqueous co-solvent solutions. In particular we compare two different methods of calculating the relevant Kirkwood-Buff integrals. The first (traditional) method computes running integrals over the radial distribution functions, which must be obtained from large system-size NVT or NpT simulations. The second, newer method, employs finite size scaling to obtain the Kirkwood-Buff integrals directly by counting the particle number fluctuations in small, open sub-volumes embedded within a larger reservoir that can be well approximated by a much smaller simulation cell. In agreement with previous studies, which made a similar comparison for aqueous co-solvent solutions, without the additional solvent, we conclude that the finite size scaling method is also applicable to the present case, since it can produce computationally more efficient results which are equivalent to the more costly radial distribution

  9. A hybrid adaptive large neighborhood search algorithm applied to a lot-sizing problem

    DEFF Research Database (Denmark)

    Muller, Laurent Flindt; Spoorendonk, Simon

    This paper presents a hybrid of a general heuristic framework that has been successfully applied to vehicle routing problems and a general purpose MIP solver. The framework uses local search and an adaptive procedure which choses between a set of large neighborhoods to be searched. A mixed integer...... of a solution and to investigate the feasibility of elements in such a neighborhood. The hybrid heuristic framework is applied to the multi-item capacitated lot sizing problem with dynamic lot sizes, where experiments have been conducted on a series of instances from the literature. On average the heuristic...

  10. Sizing and scaling requirements of a large-scale physical model for code validation

    International Nuclear Information System (INIS)

    Khaleel, R.; Legore, T.

    1990-01-01

    Model validation is an important consideration in application of a code for performance assessment and therefore in assessing the long-term behavior of the engineered and natural barriers of a geologic repository. Scaling considerations relevant to porous media flow are reviewed. An analysis approach is presented for determining the sizing requirements of a large-scale, hydrology physical model. The physical model will be used to validate performance assessment codes that evaluate the long-term behavior of the repository isolation system. Numerical simulation results for sizing requirements are presented for a porous medium model in which the media properties are spatially uncorrelated

  11. Study on external reactor vessel cooling capacity for advanced large size PWR

    International Nuclear Information System (INIS)

    Jin Di; Liu Xiaojing; Cheng Xu; Li Fei

    2014-01-01

    External reactor vessel cooling (ERVC) is widely adopted as a part of in- vessel retention (IVR) in severe accident management strategies. In this paper, some flow parameters and boundary conditions, eg., inlet and outlet area, water inlet temperature, heating power of the lower head, the annular gap size at the position of the lower head and flooding water level, were considered to qualitatively study the effect of them on natural circulation capacity of the external reactor vessel cooling for an advanced large size PWR by using RELAP5 code. And the calculation results provide some basis of analysis for the structure design and the following transient response behavior of the system. (authors)

  12. Investor mood, herding and the Ramadan effect

    OpenAIRE

    Gavriilidis, Konstantinos; Kallinterakis, Vasileios; Tsalavoutas, Ioannis

    2016-01-01

    In view of evidence linking herding and social mood, we examine whether the positive mood documented during Ramadan translates into higher herding compared to non-Ramadan days. Drawing on a sample of seven majority Muslim countries, we report significant herding during Ramadan in most of our sample markets. Additionally, we show that herding appears significantly stronger within rather than outside Ramadan for most tests whereby its significance is manifested on both Ramadan- and non-Ramadan-...

  13. Ecology of the Porcupine caribou herd

    OpenAIRE

    Kenneth R. Whitten

    1996-01-01

    Researchers have described general patterns of population regulation that fit most caribou (Rangifer tarandus) herds. Nevertheless, specific factors operating on particular populations vary greatly, and efforts to categorize herds according to the general patterns often lead to confusion. It is difficult for biologists to attempt to describe population dynamics in terms of density relationships for wide-ranging arctic caribou such as the Porcupine Herd. In these herds density varies as a func...

  14. Statistical characteristics and stability index (si) of large-sized landslide dams around the world

    International Nuclear Information System (INIS)

    Iqbal, J.; Dai, F.; Raja, I.A.

    2014-01-01

    In the last few decades, landslide dams have received greater attention of researchers, as they have caused loss to property and human lives. Over 261 large-sized landslide dams from different countries of the world with volume greater than 1 x 105 m have been reviewed for this study. The data collected for this study shows that 58% of the catastrophic landslides were triggered by earthquakes and 21 % by rainfall, revealing that earthquake and rainfall are the two major triggers, accounting for 75% of large-sized landslide dams. These land-slides were most frequent during last two decades (1990-2010) throughout the world. The mean landslide dam volume of the studied cases was 53.39 x 10 m with mean dam height of 71.98 m, while the mean lake volume was found to be 156.62 x 10 m. Failure of these large landslide dams pose a severe threat to the property and people living downstream, hence immediate attention is required to deal with this problem. A stability index (SI) has been derived on the basis on 59 large-sized landslide dams (out of the 261 dams) with complete parametric information. (author)

  15. Impacts of dairy diagnostic teams on herd performance.

    Science.gov (United States)

    Weinand, D; Conlin, B J

    2003-05-01

    This study evaluated impacts of educational diagnostic teams of consultants used to transfer technology to dairy farms. Herd management performance changes were measured by comparing Dairy Herd Improvement data from 38 project farms to data from herds that were geographical contemporaries. The value of focused goals for effecting change was also assessed. Interviews provided producers' perception of project outcomes and insight on organization and conduct of dairy diagnostic teams. Changes observed in project herds were small compared with controls with tendencies for increased herd size and improved milk production per cow. Focused goals had greater impacts on increasing herd size, milk per cow, first lactation peak milk, reducing age at first calving, and percentages of cows with subclinical mastitis. Time, money, facility limitations, labor, and alternative priorities were the most cited constraints to implementing changes. Satisfaction scores of producers were significantly related to the degree that team recommendations were followed. Improved attitudes, quality of life, and financial well-being were benefits listed by a majority of producers from participation in the project. If similar projects were to be offered, 83% said they would participate again, and 69% indicated they would pay at least some of the costs. Project farms served as demonstration farms for 1930 other producers in their respective locales, resulting in a multiplier effect of original advice given by consultant teams. Suggestions by farmer participants for improvements in dairy diagnostic teams included needs for at least some unbiased team members, more frequent meetings, more follow-up on recommendations, and consistency of recommendations with family goals.

  16. Effect of pore size on performance of monolithic tube chromatography of large biomolecules.

    Science.gov (United States)

    Podgornik, Ales; Hamachi, Masataka; Isakari, Yu; Yoshimoto, Noriko; Yamamoto, Shuichi

    2017-11-01

    Effect of pore size on the performance of ion-exchange monolith tube chromatography of large biomolecules was investigated. Radial flow 1 mL polymer based monolith tubes of different pore sizes (1.5, 2, and 6 μm) were tested with model samples such as 20 mer poly T-DNA, basic proteins, and acidic proteins (molecular weight 14 000-670 000). Pressure drop, pH transient, the number of binding site, dynamic binding capacity, and peak width were examined. Pressure drop-flow rate curves and dynamic binding capacity values were well correlated with the nominal pore size. While duration of the pH transient curves depends on the pore size, it was found that pH duration normalized on estimated surface area was constant, indicating that the ligand density is the same. This was also confirmed by the constant number of binding site values being independent of pore size. The peak width values were similar to those for axial flow monolith chromatography. These results showed that it is easy to scale up axial flow monolith chromatography to radial flow monolith tube chromatography by choosing the right pore size in terms of the pressure drop and capacity. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Large-sized and highly radioactive 3H and 109Cd Langmuir-Blodgett films

    International Nuclear Information System (INIS)

    Shibata, S.; Kawakami, H.; Kato, S.

    1994-02-01

    A device for the deposition of a radioactive Langmuir-Blodgett (LB) film was developed with the use of: (1) a modified horizontal lifting method, (2) an extremely shallow trough, and (3) a surface pressure-generating system without piston oil. It made a precious radioactive subphase solution repeatedly usable while keeping its radioactivity concentration as high as possible. Any large-size thin films can be prepared by just changing the trough size. Two monomolecular-layers of Y-type films of cadmium [ 3 H] icosanoate and 109 Cd icosanoate were built up as 3 H and 109 Cd β-sources for electron spectroscopy with intensities of 1.5 GBq (40 mCi) and 7.4 MBq (200 μCi), respectively, and a size of 65x200 mm 2 . Excellent uniformity of the distribution of deposited radioactivity was confirmed by autoradiography and photometry. (author)

  18. Detection of tiny amounts of fissile materials in large-sized containers with radioactive waste

    Science.gov (United States)

    Batyaev, V. F.; Skliarov, S. V.

    2018-01-01

    The paper is devoted to non-destructive control of tiny amounts of fissile materials in large-sized containers filled with radioactive waste (RAW). The aim of this work is to model an active neutron interrogation facility for detection of fissile ma-terials inside NZK type containers with RAW and determine the minimal detectable mass of U-235 as a function of various param-eters: matrix type, nonuniformity of container filling, neutron gen-erator parameters (flux, pulse frequency, pulse duration), meas-urement time. As a result the dependence of minimal detectable mass on fissile materials location inside container is shown. Nonu-niformity of the thermal neutron flux inside a container is the main reason of the space-heterogeneity of minimal detectable mass in-side a large-sized container. Our experiments with tiny amounts of uranium-235 (<1 g) confirm the detection of fissile materials in NZK containers by using active neutron interrogation technique.

  19. Mock-up test of remote controlled dismantling apparatus for large-sized vessels (contract research)

    Energy Technology Data Exchange (ETDEWEB)

    Myodo, Masato; Miyajima, Kazutoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Okane, Shogo [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    2001-03-01

    The Remote dismantling apparatus, which is equipped with multi-units for functioning of washing, cutting, collection of cut pieces and so on, has been constructed to dismantle the large-sized vessels in the JAERI's Reprocessing Test Facility (JRTF). The apparatus has five-axis movement capability and its operation is performed remotely. The mock-up tests were performed to evaluate the applicability of the apparatus to actual dismantling activities by using the mock-ups of LV-3 and LV-5 in the facility. It was confirmed that each unit was satisfactory functioned by remote operation. Efficient procedures for dismantling the large-sized vessel was studied and various date was obtained in the mock-up tests. This apparatus was found to be applicable for the actual dismantling activity in JRTF. (author)

  20. Mock-up test of remote controlled dismantling apparatus for large-sized vessels (contract research)

    International Nuclear Information System (INIS)

    Myodo, Masato; Miyajima, Kazutoshi; Okane, Shogo

    2001-03-01

    The Remote dismantling apparatus, which is equipped with multi-units for functioning of washing, cutting, collection of cut pieces and so on, has been constructed to dismantle the large-sized vessels in the JAERI's Reprocessing Test Facility (JRTF). The apparatus has five-axis movement capability and its operation is performed remotely. The mock-up tests were performed to evaluate the applicability of the apparatus to actual dismantling activities by using the mock-ups of LV-3 and LV-5 in the facility. It was confirmed that each unit was satisfactory functioned by remote operation. Efficient procedures for dismantling the large-sized vessel was studied and various date was obtained in the mock-up tests. This apparatus was found to be applicable for the actual dismantling activity in JRTF. (author)

  1. Influence Factors of Sports Bra Evaluation and Design Based on Large Size

    Directory of Open Access Journals (Sweden)

    Zhang Lingxi

    2016-01-01

    Full Text Available The purpose of this paper was to find the main influence factors of sports bra evaluation by the subjective assessment of different styles commercial sports bra, and to summarize the design elements of sports bra for large size. 10 women in large size (>C80 were chosen to evaluate 9 different sports bras. The main influence factors were extracted by factor analysis and all the product samples were classified by Q-cluster analysis. The conclusions show that breast stability, wearing comfort and bust modelling are the three key factors for sports bra evaluation. And a classification-positioning model of sports bra products was established. The findings can provide theoretical basis and guidance for the research and design of sports bras both for academic and sports or underwear enterprises, and also provide reference value for women customers.

  2. Comparative analysis of non-destructive methods to control fissile materials in large-size containers

    Directory of Open Access Journals (Sweden)

    Batyaev V.F.

    2017-01-01

    Full Text Available The analysis of various non-destructive methods to control fissile materials (FM in large-size containers filled with radioactive waste (RAW has been carried out. The difficulty of applying passive gamma-neutron monitoring FM in large containers filled with concreted RAW is shown. Selection of an active non-destructive assay technique depends on the container contents; and in case of a concrete or iron matrix with very low activity and low activity RAW the neutron radiation method appears to be more preferable as compared with the photonuclear one.

  3. Comparative analysis of non-destructive methods to control fissile materials in large-size containers

    Science.gov (United States)

    Batyaev, V. F.; Sklyarov, S. V.

    2017-09-01

    The analysis of various non-destructive methods to control fissile materials (FM) in large-size containers filled with radioactive waste (RAW) has been carried out. The difficulty of applying passive gamma-neutron monitoring FM in large containers filled with concreted RAW is shown. Selection of an active non-destructive assay technique depends on the container contents; and in case of a concrete or iron matrix with very low activity and low activity RAW the neutron radiation method appears to be more preferable as compared with the photonuclear one. Note to the reader: the pdf file has been changed on September 22, 2017.

  4. Development of superconducting poloidal field coils for medium and large size tokamaks

    International Nuclear Information System (INIS)

    Dittrich, H.-G.; Forster, S.; Hofmann, A.

    1983-01-01

    Large long pulse tokamak fusion experiments require the use of superconducting poloidal field (PF) coils. In the past not much attention has been paid to the development of such coils. Therefore a development programme has been initiated recently at KfK. In this report start with summarizing the relevant PF coil parameters of some medium and large size tokamaks presently under construction or design, respectively. The most important areas of research and development work are deduced from these parameters. Design considerations and first experimental results concerning low loss conductors, cooling concepts and structural components are given

  5. Scrum of scrums solution for large size teams using scrum methodology

    OpenAIRE

    Qurashi, Saja Al; Qureshi, M. Rizwan Jameel

    2014-01-01

    Scrum is a structured framework to support complex product development. However, Scrum methodology faces a challenge of managing large teams. To address this challenge, in this paper we propose a solution called Scrum of Scrums. In Scrum of Scrums, we divide the Scrum team into teams of the right size, and then organize them hierarchically into a Scrum of Scrums. The main goals of the proposed solution are to optimize communication between teams in Scrum of Scrums; to make the system work aft...

  6. A procedure to detect flaws inside large size marble blocks by ultrasound

    OpenAIRE

    Bramanti, Mauro; Bozzi, Edoardo

    1999-01-01

    In stone and marble industry there is considerable interest in the possibility of using ultrasound diagnostic techniques for non-destructive testing of large size blocks in order to detect internal flaws such as faults, cracks and fissures. In this paper some preliminary measurements are reported in order to acquire basic knowledge of the fundamental properties of ultrasound, such as propagation velocity and attenuation, in the media here considered. We then outline a particular diagnostic pr...

  7. Mechanical properties of duplex steel welded joints in large-size constructions

    OpenAIRE

    J. Nowacki

    2012-01-01

    Purpose: On the basis of sources and own experiments, the analysis of mechanical properties, applications as well as material and technological problems of ferritic-austenitic steel welding were carried out. It was shown the area of welding applications, particularly welding of large-size structures, on the basis of example of the FCAW method of welding of the UNS S3 1803 duplex steel in construction of chemical cargo ships.Design/methodology/approach: Welding tests were carried out for duple...

  8. DESIGN AND DEVELOPMENT OF A LARGE SIZE NON-TRACKING SOLAR COOKER

    Directory of Open Access Journals (Sweden)

    N. M. NAHAR

    2009-09-01

    Full Text Available A large size novel non-tracking solar cooker has been designed, developed and tested. The cooker has been designed in such a way that the width to length ratio for reflector and glass window is about 4 so that maximum radiation falls on the glass window. This has helped in eliminating azimuthal tracking that is required in simple hot box solar cooker towards the Sun every hour because the width to length ratio of reflector is 1. It has been found that stagnation temperatures were 118.5oC and 108oC in large size non-tracking solar cooker and hot box solar cooker respectively. It takes about 2 h for soft food and 3 h for hard food. The cooker is capable of cooking 4.0 kg of food at a time. The efficiency of the large size non-tracking solar cooker has been found to be 27.5%. The cooker saves 5175 MJ of energy per year. The cost of the cooker is Rs. 10000.00 (1.0 US$ = Rs. 50.50. The payback period has been calculated by considering 10% annual interest, 5% maintenance cost and 5% inflation in fuel prices and maintenance cost. The payback period is least, i.e. 1.58 yr., with respect to electricity and maximum, i.e. 4.89 yr., with respect to kerosene. The payback periods are in increasing order with respect to fuel: electricity, coal, firewood, liquid petroleum gas, and kerosene. The shorter payback periods suggests that the use of large size non-tracking solar cooker is economical.

  9. Preparation and provisional validation of a large size dried spike: Batch SAL-9931

    International Nuclear Information System (INIS)

    Jammet, G.; Zoigner, A.; Doubek, N.; Grabmueller, G.; Bagliano, G.

    1990-05-01

    To determine uranium and plutonium concentration using isotope dilution mass spectrometry, weighed aliquands of a synthetic mixture containing about 2 mg of Pu (with a 239 Pu abundance of about 98%) and 40 mg of U (with a 235 U enrichment of about 19%) have been prepared and verified by SAL to be used to spike samples of concentrated spent fuel solutions with a high burn-up and a low 235 U enrichment. The advantages of such a Large Size Dried (LSD) Spike have been pointed out elsewhere and proof of the usefulness in the field reported. Certified Reference Materials Pu-NBL-126, natural U-NBS-960 and 93% enriched U-NBL-116 were used to prepare a stock solution containing 1.8 mg/ml of Pu and 37.3 mg/ml of 19.4% enriched U. Before shipment to the Reprocessing Plant, aliquands of the stock solution are dried to give Large Size Dried Spikes which resist shocks encountered during transportation, so that they can readily be recovered quantitatively at the plant. This paper describes the preparation and the validation of a Large Size Dried Spike which is intended to be used as a common spike by the plant operator, the national and the IAEA inspectorates. 6 refs, 7 tabs

  10. Herding agent field application system development

    Energy Technology Data Exchange (ETDEWEB)

    Buist, Ian; Belore, Randy [SL Ross Environmental Research (Canada)], email: ian@slross.com

    2011-07-01

    Chemical herding agents can be applied to deal with an oil slick. This study investigates the key system components of application systems for herding agents and shows how application systems can also be developed for operational herder usage in drift ice. These two application systems are respectively required for small boat and a helicopter operations. The factors, including the selection of flow rates, pressures and atomizing nozzle types, which give the appropriate herder droplet size distributions for small boat and aerial application systems were investigated in the initial stage of the study. In a later stage, on commercializing herders for in situ burning, further research is expected to deal with the many problems not tackled in the initial stage, such as the mounting of the nozzles, pumps and reservoirs on various aerial platforms and the provision of heating and insulation for cold-weather use. The paper presented the experiments and simulations that have been conducted as well as the basic design parameters for field application systems.

  11. Folding and unfolding of large-size shell construction for application in Earth orbit

    Science.gov (United States)

    Kondyurin, Alexey; Pestrenina, Irena; Pestrenin, Valery; Rusakov, Sergey

    2016-07-01

    A future exploration of space requires a technology of large module for biological, technological, logistic and other applications in Earth orbits [1-3]. This report describes the possibility of using large-sized shell structures deployable in space. Structure is delivered to the orbit in the spaceship container. The shell is folded for the transportation. The shell material is either rigid plastic or multilayer prepreg comprising rigid reinforcements (such as reinforcing fibers). The unfolding process (bringing a construction to the unfolded state by loading the internal pressure) needs be considered at the presence of both stretching and bending deformations. An analysis of the deployment conditions (the minimum internal pressure bringing a construction from the folded state to the unfolded state) of large laminated CFRP shell structures is formulated in this report. Solution of this mechanics of deformable solids (MDS) problem of the shell structure is based on the following assumptions: the shell is made of components whose median surface has a reamer; in the separate structural element relaxed state (not stressed and not deformed) its median surface coincides with its reamer (this assumption allows choose the relaxed state of the structure correctly); structural elements are joined (sewn together) by a seam that does not resist rotation around the tangent to the seam line. The ways of large shell structures folding, whose median surface has a reamer, are suggested. Unfolding of cylindrical, conical (full and truncated cones), and large-size composite shells (cylinder-cones, cones-cones) is considered. These results show that the unfolding pressure of such large-size structures (0.01-0.2 atm.) is comparable to the deploying pressure of pneumatic parts (0.001-0.1 atm.) [3]. It would be possible to extend this approach to investigate the unfolding process of large-sized shells with ruled median surface or for non-developable surfaces. This research was

  12. Interlayer catalytic exfoliation realizing scalable production of large-size pristine few-layer graphene

    Science.gov (United States)

    Geng, Xiumei; Guo, Yufen; Li, Dongfang; Li, Weiwei; Zhu, Chao; Wei, Xiangfei; Chen, Mingliang; Gao, Song; Qiu, Shengqiang; Gong, Youpin; Wu, Liqiong; Long, Mingsheng; Sun, Mengtao; Pan, Gebo; Liu, Liwei

    2013-01-01

    Mass production of reduced graphene oxide and graphene nanoplatelets has recently been achieved. However, a great challenge still remains in realizing large-quantity and high-quality production of large-size thin few-layer graphene (FLG). Here, we create a novel route to solve the issue by employing one-time-only interlayer catalytic exfoliation (ICE) of salt-intercalated graphite. The typical FLG with a large lateral size of tens of microns and a thickness less than 2 nm have been obtained by a mild and durative ICE. The high-quality graphene layers preserve intact basal crystal planes owing to avoidance of the degradation reaction during both intercalation and ICE. Furthermore, we reveal that the high-quality FLG ensures a remarkable lithium-storage stability (>1,000 cycles) and a large reversible specific capacity (>600 mAh g-1). This simple and scalable technique acquiring high-quality FLG offers considerable potential for future realistic applications.

  13. Parasites and parasite management practices of organic and conventional dairy herds in Minnesota.

    Science.gov (United States)

    Sorge, U S; Moon, R D; Stromberg, B E; Schroth, S L; Michels, L; Wolff, L J; Kelton, D F; Heins, B J

    2015-05-01

    The objective of this study was to describe the prevalence and practices used to manage internal helminth parasites and external arthropod parasites on organic and conventional dairy herds in Minnesota. All organic (ORG) dairy herds in Minnesota (n=114) and a convenience sample of conventional herds were invited to participate in the study. Thirty-five ORG herds and 28 conventional herds were visited once in summer and fall of 2012. Conventional dairy herds were split into small conventional (SC,conventional herds (MC, ≥200 cows) so that SC herds were comparable in size to the ORG herds. Dairy managers were surveyed to assess their farm management practices and perceptions about parasites, hygiene scores were recorded for adult stock, and fecal samples were collected from a nominal 20 breeding-age heifers to characterize abundance of internal parasites. Nonparametric tests were used to compare fecal egg counts per gram (FEC) among farms grouped by management systems and practices. Organic farms had more designated pasture and were more likely to use rotational grazing compared with conventional farms, but the stocking densities of animals on pasture were similar among farm types. The overall FEC were very low, and only a few individual ORG heifers had FEC >500 eggs/gram. Samples from heifers on ORG farms had significantly more strongyle-type eggs than those on SC and MC farms (ORG: 6.6±2.1; SC: 0.5±0.3; MC: 0.8±0.7), but egg counts of other types of gastrointestinal parasites did not differ significantly among the 3 herd groups. Fly control measures were applied mainly to milking cows and preweaned calves and were used on 88.6% of ORG herds, 60.0% of SC herds, and 91.7% of MC herds. Approximately half of the producers reported having seen skin conditions suggestive of lice or tail mange in their cattle during the previous winter (ORG: 48.6%, SC: 57.1%, MC: 53.9%). Although most conventional producers reported treating these skin conditions, most organic

  14. The Fortymile caribou herd: novel proposed management and relevant biology, 1992-1997

    Directory of Open Access Journals (Sweden)

    Rodney D. Boertje

    2000-04-01

    Full Text Available A diverse, international Fortymile Planning Team wrote a novel Fortymile caribou herd {Rangifer tarandus granti Management Plan in 1995 (Boertje & Gardner, 1996: 56-77. The primary goal of this plan is to begin restoring the Fortymile herd to its former range; >70% of the herd's former range was abandoned as herd size declined. Specific objectives call for increasing the Fortymile herd by at least 5-10% annually from 1998-2002. We describe demographics of the herd, factors limiting the herd, and condition of the herd and range during 1992-1997. These data were useful in proposing management actions for the herd and should be instrumental in future evaluations of the plan's actions. The following points summarize herd biology relevant to management proposed by the Fortymile Planning Team: 1. Herd numbers remained relatively stable during 1990-1995 (about 22 000-23 000 caribou. On 21 June 1996 we counted about 900 additional caribou in the herd, probably a result of increased pregnancy rates in 1996. On 26 June 1997 we counted about 2500 additional caribou in the herd, probably a result of recruitment of the abundant 1996 calves and excellent early survival of the 1997 calves. The Team deemed that implementing management actions during a period of natural growth would be opportune. 2. Wolf (Canis lupus and grizzly bear (Ursus arctos predation were the most important sources of mortality, despite over a decade of the most liberal regulations in the state for harvesting of wolves and grizzly bears. Wolves were the most important predator. Wolves killed between 2000 and 3000 caribou calves annually during this study and between 1000 and 2300 older caribou; 1200-1900 calves were killed from May through September. No significant differences in annual wolf predation rates on calves or adults were observed between 1994 and early winter 1997. Reducing wolf predation was judged by the Team to be the most manageable way to help hasten or stimulate

  15. Risk factors for infection of sow herds with porcine reproductive and respiratory syndrome (PRRS) virus

    DEFF Research Database (Denmark)

    Mortensen, Sten; Stryhn, Henrik; Søgaard, Rikke

    2002-01-01

    In 1992, the porcine reproductive and respiratory syndrome virus (PRRSV) of European type (PRRSV-EU) was introduced in Denmark. By 1996, the virus had spread to approximately 25% of the Danish herds. In January 1996, a modified-live vaccine based on the American type of the virus (PRRSV-US) was u......In 1992, the porcine reproductive and respiratory syndrome virus (PRRSV) of European type (PRRSV-EU) was introduced in Denmark. By 1996, the virus had spread to approximately 25% of the Danish herds. In January 1996, a modified-live vaccine based on the American type of the virus (PRRSV......-US) was used in replacement boars for Danish artificial insemination (AI) centres and from July 1996, the vaccine was used in PRRSV-EU infected herds for prevention of disease. Soon after vaccine introduction, PRRSV non-infected herds experienced outbreaks of disease due to infection with PRRSV...... in the case herds). The data were analysed using a Cox-regression model. The hazard of infection increased significantly with exposure from PRRSV-US-infected neighbouring herds, purchase of animals from herds incubating PRRSV-US infection, increasing herd size and purchase of semen from boars at PRRSV...

  16. Ultra-large size austenitic stainless steel forgings for fast breeder reactor 'Monju'

    International Nuclear Information System (INIS)

    Tsukada, Hisashi; Suzuki, Komei; Sato, Ikuo; Miura, Ritsu.

    1988-01-01

    The large SUS 304 austenitic stainless steel forgings for the reactor vessel of the prototype FBR 'Monju' of 280 MWe output were successfully manufactured. The reactor vessel contains the heart of the reactor and sodium coolant at 530 deg C, and its inside diameter is about 7 m, and height is about 18 m. It is composed of 12 large forgings, that is, very thick flanges and shalls made by ring forging and an end plate made by disk forging and hot forming, using a special press machine. The manufacture of these large forgings utilized the results of the basic test on the material properties in high temperature environment and the effect that the manufacturing factors exert on the material properties and the results of the development of manufacturing techniques for superlarge forgings. The problems were the manufacturing techniques for the large ingots of 250 t class of high purity, the hot working techniques for stainless steel of fine grain size, the forging techniques for superlarge rings and disks, and the machining techniques of high precision for particularly large diameter, thin wall rings. The manufacture of these large stainless steel forgings is reported. (Kako, I.)

  17. Large Scale Behavior and Droplet Size Distributions in Crude Oil Jets and Plumes

    Science.gov (United States)

    Katz, Joseph; Murphy, David; Morra, David

    2013-11-01

    The 2010 Deepwater Horizon blowout introduced several million barrels of crude oil into the Gulf of Mexico. Injected initially as a turbulent jet containing crude oil and gas, the spill caused formation of a subsurface plume stretching for tens of miles. The behavior of such buoyant multiphase plumes depends on several factors, such as the oil droplet and bubble size distributions, current speed, and ambient stratification. While large droplets quickly rise to the surface, fine ones together with entrained seawater form intrusion layers. Many elements of the physics of droplet formation by an immiscible turbulent jet and their resulting size distribution have not been elucidated, but are known to be significantly influenced by the addition of dispersants, which vary the Weber Number by orders of magnitude. We present experimental high speed visualizations of turbulent jets of sweet petroleum crude oil (MC 252) premixed with Corexit 9500A dispersant at various dispersant to oil ratios. Observations were conducted in a 0.9 m × 0.9 m × 2.5 m towing tank, where large-scale behavior of the jet, both stationary and towed at various speeds to simulate cross-flow, have been recorded at high speed. Preliminary data on oil droplet size and spatial distributions were also measured using a videoscope and pulsed light sheet. Sponsored by Gulf of Mexico Research Initiative (GoMRI).

  18. From nanoparticles to large aerosols: Ultrafast measurement methods for size and concentration

    International Nuclear Information System (INIS)

    Keck, Lothar; Spielvogel, Juergen; Grimm, Hans

    2009-01-01

    A major challenge in aerosol technology is the fast measurement of number size distributions with good accuracy and size resolution. The dedicated instruments are frequently based on particle charging and electric detection. Established fast systems, however, still feature a number of shortcomings. We have developed a new instrument that constitutes of a high flow Differential Mobility Analyser (high flow DMA) and a high sensitivity Faraday Cup Electrometer (FCE). The system enables variable flow rates of up to 150 lpm, and the scan time for size distribution can be shortened considerably due to the short residence time of the particles in the DMA. Three different electrodes can be employed in order to cover a large size range. First test results demonstrate that the scan time can be reduced to less than 1 s for small particles, and that the results from the fast scans feature no significant difference to the results from established slow method. The fields of application for the new instrument comprise the precise monitoring of fast processes with nanoparticles, including monitoring of engine exhaust in automotive research.

  19. From nanoparticles to large aerosols: Ultrafast measurement methods for size and concentration

    Science.gov (United States)

    Keck, Lothar; Spielvogel, Jürgen; Grimm, Hans

    2009-05-01

    A major challenge in aerosol technology is the fast measurement of number size distributions with good accuracy and size resolution. The dedicated instruments are frequently based on particle charging and electric detection. Established fast systems, however, still feature a number of shortcomings. We have developed a new instrument that constitutes of a high flow Differential Mobility Analyser (high flow DMA) and a high sensitivity Faraday Cup Electrometer (FCE). The system enables variable flow rates of up to 150 lpm, and the scan time for size distribution can be shortened considerably due to the short residence time of the particles in the DMA. Three different electrodes can be employed in order to cover a large size range. First test results demonstrate that the scan time can be reduced to less than 1 s for small particles, and that the results from the fast scans feature no significant difference to the results from established slow method. The fields of application for the new instrument comprise the precise monitoring of fast processes with nanoparticles, including monitoring of engine exhaust in automotive research.

  20. Controlling herding in minority game systems

    Science.gov (United States)

    Zhang, Ji-Qiang; Huang, Zi-Gang; Wu, Zhi-Xi; Su, Riqi; Lai, Ying-Cheng

    2016-02-01

    Resource allocation takes place in various types of real-world complex systems such as urban traffic, social services institutions, economical and ecosystems. Mathematically, the dynamical process of resource allocation can be modeled as minority games. Spontaneous evolution of the resource allocation dynamics, however, often leads to a harmful herding behavior accompanied by strong fluctuations in which a large majority of agents crowd temporarily for a few resources, leaving many others unused. Developing effective control methods to suppress and eliminate herding is an important but open problem. Here we develop a pinning control method, that the fluctuations of the system consist of intrinsic and systematic components allows us to design a control scheme with separated control variables. A striking finding is the universal existence of an optimal pinning fraction to minimize the variance of the system, regardless of the pinning patterns and the network topology. We carry out a generally applicable theory to explain the emergence of optimal pinning and to predict the dependence of the optimal pinning fraction on the network topology. Our work represents a general framework to deal with the broader problem of controlling collective dynamics in complex systems with potential applications in social, economical and political systems.

  1. Problems in maintenance of herd health associated with acid forming emissions

    International Nuclear Information System (INIS)

    Kostuch, M.

    1992-01-01

    The effects of sour gas plant emissions on dairy herds are described. A veterinarian establishing a practice in Rocky Mountain House, Alberta, found that dairy herds in that area suffered from a disproportionately higher occurrence of health problems than Minnesota herds with similar types of management. These problems are postulated to result from acid-forming emissions from two large sour gas plants in the area (the Ram River and Gulf Strachan plants). Health problems found in dairy cattle in the Rocky Mountain House area were: unthriftiness, increased susceptibility to infectious diseases, reproductive problems, and 'downer' animals (cows unable to stand up unassisted). Problems related to the reproductive organs were the most apparent. Clinical observations of problems in dairy herds are described. Since the levels of emissions from the plants have decreased, incidence of problems in dairy herds has also decreased. 1 ref., 2 figs

  2. Impact basins on Ganymede and Callisto and implications for the large-projectile size distribution

    Science.gov (United States)

    Wagner, R.; Neukum, G.; Wolf, U.; Greeley, R.; Klemaszewski, J. E.

    2003-04-01

    It has been conjectured that the projectile family which impacted the Galilean Satellites of Jupiter was depleted in large projectiles, concluded from a ''dearth'' in large craters (> 60 km) (e.g. [1]). Geologic mapping, aided by spatial filtering of new Galileo as well as older Voyager data shows, however, that large projectiles have left an imprint of palimpsests and multi-ring structures on both Ganymede and Callisto (e. g. [2]). Most of these impact structures are heavily degraded and hence difficult to recognize. In this paper, we present (1) maps showing the outlines of these basins, and (2) derive updated crater size-frequency diagrams of the two satellites. The crater diameter from a palimpsest diameter was reconstructed using a formula derived by [3]. The calculation of the crater diameter Dc from the outer boundary Do of a multi-ring structure is much less constrained and on the order of Dc = k \\cdot Do , with k ≈ 0.25-0.3 [4]. Despite the uncertainties in locating the ''true'' crater rims, the resulting shape of the distribution in the range from kilometer-sized craters to sizes of ≈ 500 km is lunar-like and strongly suggests a collisionally evolved projectile family, very likely of asteroidal origin. An alternative explanation for this shape could be that comets are collisionally evolved bodies in a similar way as are asteroids, which as of yet is still uncertain and in discussion. Also, the crater size distributions on Ganymede and Callisto are shifted towards smaller crater sizes compared to the Moon, caused by a much lower impact velocity of impactors which preferentially were in planetocentric orbits [5]. References: [1] Strom et al., JGR 86, 8659-8674, 1981. [2] J. E. Klemaszewski et al., Ann. Geophys. 16, suppl. III, 1998. [3] Iaquinta-Ridolfi &Schenk, LPSC XXVI (abstr.), 651-652, 1995. [4] Schenk &Moore, LPSC XXX, abstr. No. 1786 [CD-Rom], 1999. [5] Horedt & Neukum, JGR 89, 10,405-10,410, 1984.

  3. Impact of vaccine herd-protection effects in cost-effectiveness analyses of childhood vaccinations. A quantitative comparative analysis.

    Science.gov (United States)

    Holubar, Marisa; Stavroulakis, Maria Christina; Maldonado, Yvonne; Ioannidis, John P A; Contopoulos-Ioannidis, Despina

    2017-01-01

    Inclusion of vaccine herd-protection effects in cost-effectiveness analyses (CEAs) can impact the CEAs-conclusions. However, empirical epidemiologic data on the size of herd-protection effects from original studies are limited. We performed a quantitative comparative analysis of the impact of herd-protection effects in CEAs for four childhood vaccinations (pneumococcal, meningococcal, rotavirus and influenza). We considered CEAs reporting incremental-cost-effectiveness-ratios (ICERs) (per quality-adjusted-life-years [QALY] gained; per life-years [LY] gained or per disability-adjusted-life-years [DALY] avoided), both with and without herd protection, while keeping all other model parameters stable. We calculated the size of the ICER-differences without vs with-herd-protection and estimated how often inclusion of herd-protection led to crossing of the cost-effectiveness threshold (of an assumed societal-willingness-to-pay) of $50,000 for more-developed countries or X3GDP/capita (WHO-threshold) for less-developed countries. We identified 35 CEA studies (20 pneumococcal, 4 meningococcal, 8 rotavirus and 3 influenza vaccines) with 99 ICER-analyses (55 per-QALY, 27 per-LY and 17 per-DALY). The median ICER-absolute differences per QALY, LY and DALY (without minus with herd-protection) were $15,620 (IQR: $877 to $48,376); $54,871 (IQR: $787 to $115,026) and $49 (IQR: $15 to $1,636) respectively. When the target-vaccination strategy was not cost-saving without herd-protection, inclusion of herd-protection always resulted in more favorable results. In CEAs that had ICERs above the cost-effectiveness threshold without herd-protection, inclusion of herd-protection led to crossing of that threshold in 45% of the cases. This impacted only CEAs for more developed countries, as all but one CEAs for less developed countries had ICERs below the WHO-cost-effectiveness threshold even without herd-protection. In several analyses, recommendation for the adoption of the target

  4. The new classification system for slaughter-pig herds in the Danish Salmonella surveillance-and-control program

    DEFF Research Database (Denmark)

    Alban, L.; Stege, Helle; Dahl, J.

    2002-01-01

    the Danish Salmonella Database including all herds in 2000. The classification scheme has been adjusted on the following points. (1) The sampling has been simplified into 60, 75, or 100 samples per herd per year depending on herd size. This means more-precise estimates for the seroprevalence among smaller......The Danish surveillance-and-control program for Salmonella in slaughter pigs was introduced in 1995. The key element of the program is a quick and correct identification of herds with high seroprevalence. After 5 years, the classification scheme was evaluated-and a revision was made. Data from two...

  5. Gross margin losses due to Salmonella Dublin infection in Danish dairy cattle herds estimated by simulation modelling

    DEFF Research Database (Denmark)

    Nielsen, Torben Dahl; Kudahl, Anne Braad; Østergaard, S.

    2013-01-01

    and dynamic simulation model. The model incorporated six age groups (neonatal, pre-weaned calves, weaned calves, growing heifers, breeding heifers and cows) and five infection stages (susceptible, acutely infected, carrier, super shedder and resistant). The effects of introducing one S. Dublin infectious......Salmonella Dublin affects production and animal health in cattle herds. The objective of this study was to quantify the gross margin (GM) losses following introduction and spread of S. Dublin within dairy herds. The GM losses were estimated using an age-structured stochastic, mechanistic...... with poorer management and herd size, e.g. average annual GM losses were estimated to 49 euros per stall for the first year after infection, and to 8 euros per stall annually averaged over the 10 years after herd infection for a 200 cow stall herd with very good management. In contrast, a 200 cow stall herd...

  6. Verification measurements of the IRMM-1027 and the IAEA large-sized dried (LSD) spikes

    International Nuclear Information System (INIS)

    Jakopic, R.; Aregbe, Y.; Richter, S.

    2017-01-01

    In the frame of the accountancy measurements of the fissile materials, reliable determinations of the plutonium and uranium content in spent nuclear fuel are required to comply with international safeguards agreements. Large-sized dried (LSD) spikes of enriched "2"3"5U and "2"3"9Pu for isotope dilution mass spectrometry (IDMS) analysis are routinely applied in reprocessing plants for this purpose. A correct characterisation of these elements is a pre-requirement for achieving high accuracy in IDMS analyses. This paper will present the results of external verification measurements of such LSD spikes performed by the European Commission and the International Atomic Energy Agency. (author)

  7. RESOURCE SAVING TECHNOLOGICAL PROCESS OF LARGE-SIZE DIE THERMAL TREATMENT

    Directory of Open Access Journals (Sweden)

    L. A. Glazkov

    2009-01-01

    Full Text Available The given paper presents a development of a technological process pertaining to hardening large-size parts made of die steel. The proposed process applies a water-air mixture instead of a conventional hardening medium that is industrial oil.While developing this new technological process it has been necessary to solve the following problems: reduction of thermal treatment duration, reduction of power resource expense (natural gas and mineral oil, elimination of fire danger and increase of process ecological efficiency. 

  8. Estimation of the sizes of hot nuclear systems from particle-particle large angle kinematical correlations

    International Nuclear Information System (INIS)

    La Ville, J.L.; Bizard, G.; Durand, D.; Jin, G.M.; Rosato, E.

    1990-06-01

    Light fragment emission, when triggered by large transverse momentum protons shows specific kinematical correlations due to recoil effects of the excited emitting source. Such effects have been observed in azimuthal angular distributions of He-particles produced in collisions induced by 94 MeV/u 16 0 ions on Al, Ni and Au targets. A model calculation assuming a two-stage mechanism (formation and sequential decay of a hot source) gives a good description of these whole data. From this succesfull confrontation, it is possible to estimate the size of the emitting system

  9. Introduction to Large-sized Test Facility for validating Containment Integrity under Severe Accidents

    International Nuclear Information System (INIS)

    Na, Young Su; Hong, Seongwan; Hong, Seongho; Min, Beongtae

    2014-01-01

    An overall assessment of containment integrity can be conducted properly by examining the hydrogen behavior in the containment building. Under severe accidents, an amount of hydrogen gases can be generated by metal oxidation and corium-concrete interaction. Hydrogen behavior in the containment building strongly depends on complicated thermal hydraulic conditions with mixed gases and steam. The performance of a PAR can be directly affected by the thermal hydraulic conditions, steam contents, gas mixture behavior and aerosol characteristics, as well as the operation of other engineering safety systems such as a spray. The models in computer codes for a severe accident assessment can be validated based on the experiment results in a large-sized test facility. The Korea Atomic Energy Research Institute (KAERI) is now preparing a large-sized test facility to examine in detail the safety issues related with hydrogen including the performance of safety devices such as a PAR in various severe accident situations. This paper introduces the KAERI test facility for validating the containment integrity under severe accidents. To validate the containment integrity, a large-sized test facility is necessary for simulating complicated phenomena induced by an amount of steam and gases, especially hydrogen released into the containment building under severe accidents. A pressure vessel 9.5 m in height and 3.4 m in diameter was designed at the KAERI test facility for the validating containment integrity, which was based on the THAI test facility with the experimental safety and the reliable measurement systems certified for a long time. This large-sized pressure vessel operated in steam and iodine as a corrosive agent was made by stainless steel 316L because of corrosion resistance for a long operating time, and a vessel was installed in at KAERI in March 2014. In the future, the control systems for temperature and pressure in a vessel will be constructed, and the measurement system

  10. Investigation of Low-Cost Surface Processing Techniques for Large-Size Multicrystalline Silicon Solar Cells

    OpenAIRE

    Cheng, Yuang-Tung; Ho, Jyh-Jier; Lee, William J.; Tsai, Song-Yeu; Lu, Yung-An; Liou, Jia-Jhe; Chang, Shun-Hsyung; Wang, Kang L.

    2010-01-01

    The subject of the present work is to develop a simple and effective method of enhancing conversion efficiency in large-size solar cells using multicrystalline silicon (mc-Si) wafer. In this work, industrial-type mc-Si solar cells with area of 125×125 mm2 were acid etched to produce simultaneously POCl3 emitters and silicon nitride deposition by plasma-enhanced chemical vapor deposited (PECVD). The study of surface morphology and reflectivity of different mc-Si etched surfaces has also been d...

  11. Development and introduction of stamping technique for large-size laterals of NPP pipelines

    International Nuclear Information System (INIS)

    Romashko, N.I.; Moshnin, E.N.; Timokhin, V.S.; Bryukhanov, Yu.V.; Lebedev, V.A.

    1984-01-01

    The results of development and introduction of stamping technique for large-size laterals of NPP high-pressure pipelines are presented. The main experimental data characterizing technological possibilities of the process are given. The technological process and design of the stamp assure production of laterals from ovalized bars per one heating of the bar and per one running of the press cronnhead. Introduction of new technology decreased labour input of lateral production, reliability and serviceability of pipelines increased in this case. Introduction of this technology gives a considerable benefit

  12. A simple, compact, and rigid piezoelectric step motor with large step size

    Science.gov (United States)

    Wang, Qi; Lu, Qingyou

    2009-08-01

    We present a novel piezoelectric stepper motor featuring high compactness, rigidity, simplicity, and any direction operability. Although tested in room temperature, it is believed to work in low temperatures, owing to its loose operation conditions and large step size. The motor is implemented with a piezoelectric scanner tube that is axially cut into almost two halves and clamp holds a hollow shaft inside at both ends via the spring parts of the shaft. Two driving voltages that singly deform the two halves of the piezotube in one direction and recover simultaneously will move the shaft in the opposite direction, and vice versa.

  13. Temperature Uniformity of Wafer on a Large-Sized Susceptor for a Nitride Vertical MOCVD Reactor

    International Nuclear Information System (INIS)

    Li Zhi-Ming; Jiang Hai-Ying; Han Yan-Bin; Li Jin-Ping; Yin Jian-Qin; Zhang Jin-Cheng

    2012-01-01

    The effect of coil location on wafer temperature is analyzed in a vertical MOCVD reactor by induction heating. It is observed that the temperature distribution in the wafer with the coils under the graphite susceptor is more uniform than that with the coils around the outside wall of the reactor. For the case of coils under the susceptor, we find that the thickness of the susceptor, the distance from the coils to the susceptor bottom and the coil turns significantly affect the temperature uniformity of the wafer. An optimization process is executed for a 3-inch susceptor with this kind of structure, resulting in a large improvement in the temperature uniformity. A further optimization demonstrates that the new susceptor structure is also suitable for either multiple wafers or large-sized wafers approaching 6 and 8 inches

  14. Accelerating inference for diffusions observed with measurement error and large sample sizes using approximate Bayesian computation

    DEFF Research Database (Denmark)

    Picchini, Umberto; Forman, Julie Lyng

    2016-01-01

    a nonlinear stochastic differential equation model observed with correlated measurement errors and an application to protein folding modelling. An approximate Bayesian computation (ABC)-MCMC algorithm is suggested to allow inference for model parameters within reasonable time constraints. The ABC algorithm......In recent years, dynamical modelling has been provided with a range of breakthrough methods to perform exact Bayesian inference. However, it is often computationally unfeasible to apply exact statistical methodologies in the context of large data sets and complex models. This paper considers...... applications. A simulation study is conducted to compare our strategy with exact Bayesian inference, the latter resulting two orders of magnitude slower than ABC-MCMC for the considered set-up. Finally, the ABC algorithm is applied to a large size protein data. The suggested methodology is fairly general...

  15. Effects of herd management practices on somatic cell counts in an arid climate

    Directory of Open Access Journals (Sweden)

    Ali Sadeghi-Sefidmazgi

    2014-09-01

    Full Text Available The objective of this study was to evaluate associations between average lactation somatic cell counts (SCC and herd management practices in an arid climate. A total of 38,530 average lactation SCC records for 10,216 Holstein cows gathered on 25 dairy farms from January 2009 to October 2012 in Isfahan (Iran were analyzed. Average lactation SCC (cells × 1,000 was 250.79 ranging from 90.31 to 483.23 cells/mL across investigated farms. Herd-level management factors associated with average lactation SCC were determined separately using mixed linear models in the MIXED procedure with average lactation somatic cell score (SCS included as the dependent variable. Some of the management practices associated with low average lactation SCS included sawdust combined with sand bedding, using automatic cup removers, disinfection of the teats by dipping into disinfectant, using washable towels for teat cleaning, free-stall barns, wet disposable tissue for udder washing, wearing gloves during milking and the use of humidifiers and shade. Lower-production herds and larger-size herds had lower average lactation somatic cell counts. Most herd management practices associated with average lactation SCC in dairy herds in the arid region of Isfahan are in agreement with most previous studies. However, different results are found for use of humidifier, bedding materials and herd size.

  16. Risk factors for Coxiella burnetii antibodies in bulk tank milk from Danish dairy herds

    DEFF Research Database (Denmark)

    Agger, Jens Frederik; Paul, Suman; Christoffersen, Anna-Bodil

    2013-01-01

    .2), artificial insemination by other people than artificial insemination technicians (OR = 7.7), routine herd health contract with the veterinarian (OR = 4.3) and hygiene precautions taken by veterinarians (OR = 5). In addition, herd size, hired labour, trading of cattle between farms, quarantine and use...

  17. Application of electron beam welding to large size pressure vessels made of thick low alloy steel

    International Nuclear Information System (INIS)

    Kuri, S.; Yamamoto, M.; Aoki, S.; Kimura, M.; Nayama, M.; Takano, G.

    1993-01-01

    The authors describe the results of studies for application of the electron beam welding to the large size pressure vessels made of thick low alloy steel (ASME A533 Gr.B cl.2 and A533 Gr.A cl.1). Two major problems for applying the EBW, the poor toughness of weld metal and the equipment to weld huge pressure vessels are focused on. For the first problem, the effects of Ni content of weld metal, welding conditions and post weld heat treatment are investigated. For the second problem, an applicability of the local vacuum EBW to a large size pressure vessel made of thick plate is qualified by the construction of a 120 mm thick, 2350 mm outside diameter cylindrical model. The model was electron beam welded using local vacuum chamber and the performance of the weld joint is investigated. Based on these results, the electron beam welding has been applied to the production of a steam generator for a PWR. (author). 3 refs., 10 figs., 4 tabs

  18. A new type of intelligent wireless sensing network for health monitoring of large-size structures

    Science.gov (United States)

    Lei, Ying; Liu, Ch.; Wu, D. T.; Tang, Y. L.; Wang, J. X.; Wu, L. J.; Jiang, X. D.

    2009-07-01

    In recent years, some innovative wireless sensing systems have been proposed. However, more exploration and research on wireless sensing systems are required before wireless systems can substitute for the traditional wire-based systems. In this paper, a new type of intelligent wireless sensing network is proposed for the heath monitoring of large-size structures. Hardware design of the new wireless sensing units is first studied. The wireless sensing unit mainly consists of functional modules of: sensing interface, signal conditioning, signal digitization, computational core, wireless communication and battery management. Then, software architecture of the unit is introduced. The sensing network has a two-level cluster-tree architecture with Zigbee communication protocol. Important issues such as power saving and fault tolerance are considered in the designs of the new wireless sensing units and sensing network. Each cluster head in the network is characterized by its computational capabilities that can be used to implement the computational methodologies of structural health monitoring; making the wireless sensing units and sensing network have "intelligent" characteristics. Primary tests on the measurement data collected by the wireless system are performed. The distributed computational capacity of the intelligent sensing network is also demonstrated. It is shown that the new type of intelligent wireless sensing network provides an efficient tool for structural health monitoring of large-size structures.

  19. Detection of tiny amounts of fissile materials in large-sized containers with radioactive waste

    Directory of Open Access Journals (Sweden)

    Batyaev V.F.

    2018-01-01

    Full Text Available The paper is devoted to non-destructive control of tiny amounts of fissile materials in large-sized containers filled with radioactive waste (RAW. The aim of this work is to model an active neutron interrogation facility for detection of fissile ma-terials inside NZK type containers with RAW and determine the minimal detectable mass of U-235 as a function of various param-eters: matrix type, nonuniformity of container filling, neutron gen-erator parameters (flux, pulse frequency, pulse duration, meas-urement time. As a result the dependence of minimal detectable mass on fissile materials location inside container is shown. Nonu-niformity of the thermal neutron flux inside a container is the main reason of the space-heterogeneity of minimal detectable mass in-side a large-sized container. Our experiments with tiny amounts of uranium-235 (<1 g confirm the detection of fissile materials in NZK containers by using active neutron interrogation technique.

  20. An automated system for the preparation of Large Size Dried (LSD) Spikes

    Energy Technology Data Exchange (ETDEWEB)

    Verbruggen, A.; Bauwens, J.; Jakobsson, U.; Eykens, R.; Wellum, R.; Aregbe, Y. [European Commission - Joint Research Centre, Institute for Reference Materials and Measurements (IRMM), Retieseweg 211, B2440 Geel (Belgium); Van De Steene, N. [Nucomat, Mercatorstraat 206, B9100 Sint Niklaas (Belgium)

    2008-07-01

    Large size dried (LSD) spikes have been produced to fulfill the existing requirement for reliable and traceable isotopic reference materials for nuclear safeguards. A system to produce certified nuclear isotopic reference material as a U/Pu mixture in the form of large size dried spikes, comparable to those produced using traditional methods has been installed in collaboration with Nucomat, a company with a recognized reputation in design and development of integrated automated systems. The major components of the system are a robot, two balances, a dispenser and a drying unit fitted into a glove box. The robot is software driven and designed to control all movements inside the glove-box, to identify unambiguously the penicillin vials with a bar-code reader, to dispense the LSD batch solution into the vials and to weigh the amount dispensed. The system functionality has been evaluated and the performance validated by comparing the results from a series of samples dispensed and weighed by the automated system with the results by manual substitution weighing. After applying the proper correction factors to the data from the automated system balance no significant difference was observed between the two. However, an additional component of uncertainty of 3*10{sup -4} is introduced in the uncertainty budget for the certified weights provided by the automatic system. (authors)

  1. An automated system for the preparation of Large Size Dried (LSD) Spikes

    International Nuclear Information System (INIS)

    Verbruggen, A.; Bauwens, J.; Jakobsson, U.; Eykens, R.; Wellum, R.; Aregbe, Y.; Van De Steene, N.

    2008-01-01

    Large size dried (LSD) spikes have been produced to fulfill the existing requirement for reliable and traceable isotopic reference materials for nuclear safeguards. A system to produce certified nuclear isotopic reference material as a U/Pu mixture in the form of large size dried spikes, comparable to those produced using traditional methods has been installed in collaboration with Nucomat, a company with a recognized reputation in design and development of integrated automated systems. The major components of the system are a robot, two balances, a dispenser and a drying unit fitted into a glove box. The robot is software driven and designed to control all movements inside the glove-box, to identify unambiguously the penicillin vials with a bar-code reader, to dispense the LSD batch solution into the vials and to weigh the amount dispensed. The system functionality has been evaluated and the performance validated by comparing the results from a series of samples dispensed and weighed by the automated system with the results by manual substitution weighing. After applying the proper correction factors to the data from the automated system balance no significant difference was observed between the two. However, an additional component of uncertainty of 3*10 -4 is introduced in the uncertainty budget for the certified weights provided by the automatic system. (authors)

  2. Q0000-398 is a high-redshift quasar with a large angular size

    International Nuclear Information System (INIS)

    Gearhart, M.R.; Pacht, E.

    1977-01-01

    A study is described, using the three-element interferrometer at the National Radio Astronomy Observatory, West Virginia, to investigate whether any quasars exist that might be radio sources. It was found that Q0000-398 appeared to be a quasar of high red shift and large angular size. The interferrometer was operated with a 300-1200-1500 m baseline configuration at 2695 MHz. The radio map for Q0000-398 is shown, and has two weak components separated by 134 +- 40 arc s. If these components are associated with the optical object this quasar has the largest known angular size for its red shift value. The results reported for Q0000-398 and other quasars having considerable angular extent demonstrate the importance of considering radio selection effects in the angular diameter-red shift relationship, and since any radio selection effects are removed when quasars are selected optically, more extensive mapping programs should be undertaken, looking particularly for large scale structure around optically selected high-z quasars. (U.K.)

  3. Are large farms more efficient? Tenure security, farm size and farm efficiency: evidence from northeast China

    Science.gov (United States)

    Zhou, Yuepeng; Ma, Xianlei; Shi, Xiaoping

    2017-04-01

    How to increase production efficiency, guarantee grain security, and increase farmers' income using the limited farmland is a great challenge that China is facing. Although theory predicts that secure property rights and moderate scale management of farmland can increase land productivity, reduce farm-related costs, and raise farmer's income, empirical studies on the size and magnitude of these effects are scarce. A number of studies have examined the impacts of land tenure or farm size on productivity or efficiency, respectively. There are also a few studies linking farm size, land tenure and efficiency together. However, to our best knowledge, there are no studies considering tenure security and farm efficiency together for different farm scales in China. In addition, there is little study analyzing the profit frontier. In this study, we particularly focus on the impacts of land tenure security and farm size on farm profit efficiency, using farm level data collected from 23 villages, 811 households in Liaoning in 2015. 7 different farm scales have been identified to further represent small farms, median farms, moderate-scale farms, and large farms. Technical efficiency is analyzed with stochastic frontier production function. The profit efficiency is regressed on a set of explanatory variables which includes farm size dummies, land tenure security indexes, and household characteristics. We found that: 1) The technical efficiency scores for production efficiency (average score = 0.998) indicate that it is already very close to the production frontier, and thus there is little room to improve production efficiency. However, there is larger space to raise profit efficiency (average score = 0.768) by investing more on farm size expansion, seed, hired labor, pesticide, and irrigation. 2) Farms between 50-80 mu are most efficient from the viewpoint of profit efficiency. The so-called moderate-scale farms (100-150 mu) according to the governmental guideline show no

  4. Herd-level risk factors for Campylobacter fetus infection, Brucella seropositivity and within-herd seroprevalence of brucellosis in cattle in northern Nigeria.

    Science.gov (United States)

    Mai, H M; Irons, P C; Kabir, J; Thompson, P N

    2013-09-01

    Brucellosis and campylobacteriosis are economically important diseases affecting bovine reproductive efficiency in Nigeria. A questionnaire-based survey was conducted in 271 cattle herds in Adamawa, Kaduna and Kano states of northern Nigeria using multistage cluster sampling. Serum from 4745 mature animals was tested for Brucella antibodies using the Rose-Bengal plate test and positives were confirmed in series-testing protocol using competitive enzyme-linked immunosorbent assay. Preputial scrapings from 602 bulls were tested using culture and identification for Campylobacter fetus. For each disease, a herd was classified as positive if one or more animals tested positive. For each herd, information on potential managemental and environmental risk factors was collected through a questionnaire administered during an interview with the manager, owner or herdsman. Multiple logistic regression models were used to model the odds of herd infection for each disease. A zero-inflated Poisson model was used to model the count of Brucella-positive animals within herds, with the number tested as an exposure variable. The presence of small ruminants (sheep and/or goats) on the same farm, and buying-in of >3 new animals in the previous year or failure to practice quarantine were associated with increased odds of herd-level campylobacteriosis and brucellosis, as well as increased within-herd counts of Brucella-positive animals. In addition, high rainfall, initial acquisition of animals from markets, practice of gynaecological examination and failure to practice herd prophylactic measures were positively associated with the odds of C. fetus infection in the herd. Herd size of >15, pastoral management system and presence of handling facility on the farm were associated with increased odds, and gynaecological examination with reduced odds of herd-level Brucella seropositivity. Furthermore, the zero-inflated Poisson model showed that borrowing or sharing of bulls was associated with

  5. —Does Demand Fall When Customers Perceive That Prices Are Unfair? The Case of Premium Pricing for Large Sizes

    OpenAIRE

    Eric T. Anderson; Duncan I. Simester

    2008-01-01

    We analyze a large-scale field test conducted with a mail-order catalog firm to investigate how customers react to premium prices for larger sizes of women's apparel. We find that customers who demand large sizes react unfavorably to paying a higher price than customers for small sizes. Further investigation suggests that these consumers perceive that the price premium is unfair. Overall, premium pricing led to a 6% to 8% decrease in gross profits.

  6. Ulysses: accurate detection of low-frequency structural variations in large insert-size sequencing libraries.

    Science.gov (United States)

    Gillet-Markowska, Alexandre; Richard, Hugues; Fischer, Gilles; Lafontaine, Ingrid

    2015-03-15

    The detection of structural variations (SVs) in short-range Paired-End (PE) libraries remains challenging because SV breakpoints can involve large dispersed repeated sequences, or carry inherent complexity, hardly resolvable with classical PE sequencing data. In contrast, large insert-size sequencing libraries (Mate-Pair libraries) provide higher physical coverage of the genome and give access to repeat-containing regions. They can thus theoretically overcome previous limitations as they are becoming routinely accessible. Nevertheless, broad insert size distributions and high rates of chimerical sequences are usually associated to this type of libraries, which makes the accurate annotation of SV challenging. Here, we present Ulysses, a tool that achieves drastically higher detection accuracy than existing tools, both on simulated and real mate-pair sequencing datasets from the 1000 Human Genome project. Ulysses achieves high specificity over the complete spectrum of variants by assessing, in a principled manner, the statistical significance of each possible variant (duplications, deletions, translocations, insertions and inversions) against an explicit model for the generation of experimental noise. This statistical model proves particularly useful for the detection of low frequency variants. SV detection performed on a large insert Mate-Pair library from a breast cancer sample revealed a high level of somatic duplications in the tumor and, to a lesser extent, in the blood sample as well. Altogether, these results show that Ulysses is a valuable tool for the characterization of somatic mosaicism in human tissues and in cancer genomes. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  7. Statistical characterization of a large geochemical database and effect of sample size

    Science.gov (United States)

    Zhang, C.; Manheim, F.T.; Hinde, J.; Grossman, J.N.

    2005-01-01

    smaller numbers of data points showed that few elements passed standard statistical tests for normality or log-normality until sample size decreased to a few hundred data points. Large sample size enhances the power of statistical tests, and leads to rejection of most statistical hypotheses for real data sets. For large sample sizes (e.g., n > 1000), graphical methods such as histogram, stem-and-leaf, and probability plots are recommended for rough judgement of probability distribution if needed. ?? 2005 Elsevier Ltd. All rights reserved.

  8. Analyzing Damping Vibration Methods of Large-Size Space Vehicles in the Earth's Magnetic Field

    Directory of Open Access Journals (Sweden)

    G. A. Shcheglov

    2016-01-01

    Full Text Available It is known that most of today's space vehicles comprise large antennas, which are bracket-attached to the vehicle body. Dimensions of reflector antennas may be of 30 ... 50 m. The weight of such constructions can reach approximately 200 kg.Since the antenna dimensions are significantly larger than the size of the vehicle body and the points to attach the brackets to the space vehicles have a low stiffness, conventional dampers may be inefficient. The paper proposes to consider the damping antenna in terms of its interaction with the Earth's magnetic field.A simple dynamic model of the space vehicle equipped with a large-size structure is built. The space vehicle is a parallelepiped to which the antenna is attached through a beam.To solve the model problems, was used a simplified model of Earth's magnetic field: uniform, with intensity lines parallel to each other and perpendicular to the plane of the antenna.The paper considers two layouts of coils with respect to the antenna, namely: a vertical one in which an axis of magnetic dipole is perpendicular to the antenna plane, and a horizontal layout in which an axis of magnetic dipole lies in the antenna plane. It also explores two ways for magnetic damping of oscillations: through the controlled current that is supplied from the power supply system of the space vehicle, and by the self-induction current in the coil. Thus, four objectives were formulated.In each task was formulated an oscillation equation. Then a ratio of oscillation amplitudes and their decay time were estimated. It was found that each task requires the certain parameters either of the antenna itself, its dimensions and moment of inertia, or of the coil and, respectively, the current, which is supplied from the space vehicle. In each task for these parameters were found the ranges, which allow us to tell of efficient damping vibrations.The conclusion can be drawn based on the analysis of tasks that a specialized control system

  9. Diagnostic herd sensitivity using environmental samples

    DEFF Research Database (Denmark)

    Vigre, Håkan; Josefsen, Mathilde Hartmann; Seyfarth, Anne Mette

    either at farm or slaughter. Three sample matrices were collected; dust samples (5 environmental swabs), nasal swabs (10 pools with 5 animals per pool) and air samples (1 filter). Based on the assumption that MRSA occurred in all 48 herds the overall herd sensitivity was 58% for nasal swabs, 33% for dust....... In our example, the prevalence of infected pigs in each herd was estimated from the pooled samples of nasal swabs. Logistic regression was used to estimate the effect of animal prevalence on the probability to detect MRSA in the dust and air samples at herd level. The results show a significant increase...

  10. Understanding herding based on a co-evolutionary model for strategy and game structure

    International Nuclear Information System (INIS)

    Wang, Tao; Huang, Keke; Cheng, Yuan; Zheng, Xiaoping

    2015-01-01

    Highlights: •We model herding effect in emergency from perspective of evolutionary game theory. •Rational subpopulation survives only when the game parameter is significantly large. •Herding effect may arise if the relative rewarding for rational agents is small. •Increasing the relative rewarding for rational agents will prevent herding effect. •The evolution result is unstable if the game parameter approaches critical points. -- Abstract: So far, there has been no conclusion on the mechanism for herding, which is often discussed in the academia. Assuming escaping behavior of individuals in emergency is rational rather than out of panic according to recent findings in social psychology, we investigate the behavioral evolution of large crowds from the perspective of evolutionary game theory. Specifically, evolution of the whole population divided into two subpopulations, namely the co-evolution of strategy and game structure, is numerically simulated based on the game theoretical models built and the evolutionary rule designed, and a series of phenomena including extinction of one subpopulation and herding effect are predicted in the proposed framework. Furthermore, if the rewarding for rational agents becomes significantly larger than that for emotional ones, herding effect will disappear. It is exciting that some phase transition points with interesting properties for the system can be found. In addition, our model framework is able to explain the fact that it is difficult for mavericks to prevail in society. The current results of this work will be helpful in understanding and restraining herding effect in real life

  11. Short communication: Microbiological quality of raw cow milk and its association with herd management practices in Northern China.

    Science.gov (United States)

    Lan, X Y; Zhao, S G; Zheng, N; Li, S L; Zhang, Y D; Liu, H M; McKillip, J; Wang, J Q

    2017-06-01

    Contamination of raw milk with bacterial pathogens is potentially hazardous to human health. The aim of this study was to evaluate the total bacteria count (TBC) and presence of pathogens in raw milk in Northern China along with the associated herd management practices. A total of 160 raw milk samples were collected from 80 dairy herds in Northern China. All raw milk samples were analyzed for TBC and pathogens by culturing. The results showed that the number of raw milk samples with TBC milk samples were Staphylococcus aureus positive, 72 (45.00%) were Escherichia coli positive, 2 (1.25%) were Salmonella positive, 2 (1.25%) were Listeria monocytogenes positive, and 3 (1.88%) were Campylobacter positive. The prevalence of S. aureus was influenced by season, herd size, milking frequency, disinfection frequency, and use of a Dairy Herd Improvement program. The TBC was influenced by season and milk frequency. The correlation between TBC and prevalence of S. aureus or E. coli is significant. The effect size statistical analysis showed that season and herd (but not Dairy Herd Improvement, herd size, milking frequency, disinfection frequency, and area) were the most important factors affecting TBC in raw milk. In conclusion, the presence of bacteria in raw milk was associated with season and herd management practices, and further comprehensive study will be powerful for effectively characterizing various factors affecting milk microbial quality in bulk tanks in China. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  12. Flow induced vibration of the large-sized sodium valve for MONJU

    International Nuclear Information System (INIS)

    Sato, K.

    1977-01-01

    Measurements have been made on the hydraulic characteristics of the large-sized sodium valves in the hydraulic simulation test loop with water as fluid. The following three prototype sodium valves were tested; (1) 22-inch wedge gate type isolation valve, (2) 22-inch butterfly type isolation valve, and (3) 16-inch butterfly type control valve. In the test, accelerations of flow induced vibrations were measured as a function of flow velocity and disk position. The excitation mechanism of the vibrations is not fully interpreted in these tests due to the complexity of the phenomena, but the experimental results suggest that it closely depends on random pressure fluctuations near the valve disk and flow separation at the contracted cross section between the valve seat and the disk. The intensity of flow induced vibrations suddenly increases at a certain critical condition, which depends on the type of valve and is proportional to fluid velocity. (author)

  13. Flow induced vibration of the large-sized sodium valve for MONJU

    Energy Technology Data Exchange (ETDEWEB)

    Sato, K [Sodium Engineering Division, O-arai Engineering Centre, Power Reactor and Nuclear Fuel Development Corporation, Nariata-cho, O-arai Machi, Ibaraki-ken (Japan)

    1977-12-01

    Measurements have been made on the hydraulic characteristics of the large-sized sodium valves in the hydraulic simulation test loop with water as fluid. The following three prototype sodium valves were tested; (1) 22-inch wedge gate type isolation valve, (2) 22-inch butterfly type isolation valve, and (3) 16-inch butterfly type control valve. In the test, accelerations of flow induced vibrations were measured as a function of flow velocity and disk position. The excitation mechanism of the vibrations is not fully interpreted in these tests due to the complexity of the phenomena, but the experimental results suggest that it closely depends on random pressure fluctuations near the valve disk and flow separation at the contracted cross section between the valve seat and the disk. The intensity of flow induced vibrations suddenly increases at a certain critical condition, which depends on the type of valve and is proportional to fluid velocity. (author)

  14. A Novel Read Scheme for Large Size One-Resistor Resistive Random Access Memory Array.

    Science.gov (United States)

    Zackriya, Mohammed; Kittur, Harish M; Chin, Albert

    2017-02-10

    The major issue of RRAM is the uneven sneak path that limits the array size. For the first time record large One-Resistor (1R) RRAM array of 128x128 is realized, and the array cells at the worst case still have good Low-/High-Resistive State (LRS/HRS) current difference of 378 nA/16 nA, even without using the selector device. This array has extremely low read current of 9.7 μA due to both low-current RRAM device and circuit interaction, where a novel and simple scheme of a reference point by half selected cell and a differential amplifier (DA) were implemented in the circuit design.

  15. Study on growth techniques and macro defects of large-size Nd:YAG laser crystal

    Science.gov (United States)

    Quan, Jiliang; Yang, Xin; Yang, Mingming; Ma, Decai; Huang, Jinqiang; Zhu, Yunzhong; Wang, Biao

    2018-02-01

    Large-size neodymium-doped yttrium aluminum garnet (Nd:YAG) single crystals were grown by the Czochralski method. The extinction ratio and wavefront distortion of the crystal were tested to determine the optical homogeneity. Moreover, under different growth conditions, the macro defects of inclusion, striations, and cracking in the as-grown Nd:YAG crystals were analyzed. Specifically, the inclusion defects were characterized using scanning electron microscopy and energy dispersive spectroscopy. The stresses of growth striations and cracking were studied via a parallel plane polariscope. These results demonstrate that improper growth parameters and temperature fields can enhance defects significantly. Thus, by adjusting the growth parameters and optimizing the thermal environment, high-optical-quality Nd:YAG crystals with a diameter of 80 mm and a total length of 400 mm have been obtained successfully.

  16. 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

  17. Preparation and validation of a large size dried spike: Batch SAL-9924

    International Nuclear Information System (INIS)

    Bagliano, G.; Cappis, J.; Doubek, N.; Jammet, G.; Raab, W.; Zoigner, A.

    1989-12-01

    To determine uranium and plutonium concentration using isotope dilution mass spectrometry, weighed aliquands of a synthetic mixture containing 2 to 4 mg of Pu (with a 239 Pu abundance of about 97%) and 40 to 200 mg of U (with a 235 U enrichment of about 18%) can be advantageously used to spike a concentrated spent fuel solution with a high burn up and with a low 235 U enrichment. This will simplify the conditioning of the sample by 1) reduced time of preparation (from more than one day used for the conventional technique to 2-3 hours); 2) reduced burden for the operator with a clear easiness for the inspector to witness the entire procedure (accurate dilution of the spent fuel sample before spiking being no longer necessary). Furthermore this type of spike could be used as a common spike for the operator and the inspector. The source materials are available in sufficient quantity and are enough cheaper than the commonly used 233 U and 242 Pu or 244 Pu tracer that the costs of the overall Operator-Inspector procedures will be reduced. Certified Reference Materials Pu-NBL-126, natural U-NBS-960 and 93% enriched U-NBL-116 were used to prepare a stock solution containing 1.7 mg/ml of Pu and 68 mg/ml of 17.5% enriched U. Before shipment to the Reprocessing Plant, aliquands of the stock solution must be dried to give Large Size Dried Spikes which resist shocks encountered during transportation, so that they can readily be recovered quantitatively at the plant. This paper describes the preparation and the validation of the Large Size Dried Spike. Proof of usefulness in the field will be done at a later date in parallel with analysis by the conventional technique. Refs and tabs

  18. Fiber-chip edge coupler with large mode size for silicon photonic wire waveguides.

    Science.gov (United States)

    Papes, Martin; Cheben, Pavel; Benedikovic, Daniel; Schmid, Jens H; Pond, James; Halir, Robert; Ortega-Moñux, Alejandro; Wangüemert-Pérez, Gonzalo; Ye, Winnie N; Xu, Dan-Xia; Janz, Siegfried; Dado, Milan; Vašinek, Vladimír

    2016-03-07

    Fiber-chip edge couplers are extensively used in integrated optics for coupling of light between planar waveguide circuits and optical fibers. In this work, we report on a new fiber-chip edge coupler concept with large mode size for silicon photonic wire waveguides. The coupler allows direct coupling with conventional cleaved optical fibers with large mode size while circumventing the need for lensed fibers. The coupler is designed for 220 nm silicon-on-insulator (SOI) platform. It exhibits an overall coupling efficiency exceeding 90%, as independently confirmed by 3D Finite-Difference Time-Domain (FDTD) and fully vectorial 3D Eigenmode Expansion (EME) calculations. We present two specific coupler designs, namely for a high numerical aperture single mode optical fiber with 6 µm mode field diameter (MFD) and a standard SMF-28 fiber with 10.4 µm MFD. An important advantage of our coupler concept is the ability to expand the mode at the chip edge without leading to high substrate leakage losses through buried oxide (BOX), which in our design is set to 3 µm. This remarkable feature is achieved by implementing in the SiO 2 upper cladding thin high-index Si 3 N 4 layers. The Si 3 N 4 layers increase the effective refractive index of the upper cladding near the facet. The index is controlled along the taper by subwavelength refractive index engineering to facilitate adiabatic mode transformation to the silicon wire waveguide while the Si-wire waveguide is inversely tapered along the coupler. The mode overlap optimization at the chip facet is carried out with a full vectorial mode solver. The mode transformation along the coupler is studied using 3D-FDTD simulations and with fully-vectorial 3D-EME calculations. The couplers are optimized for operating with transverse electric (TE) polarization and the operating wavelength is centered at 1.55 µm.

  19. Development of high sensitivity and high speed large size blank inspection system LBIS

    Science.gov (United States)

    Ohara, Shinobu; Yoshida, Akinori; Hirai, Mitsuo; Kato, Takenori; Moriizumi, Koichi; Kusunose, Haruhiko

    2017-07-01

    The production of high-resolution flat panel displays (FPDs) for mobile phones today requires the use of high-quality large-size photomasks (LSPMs). Organic light emitting diode (OLED) displays use several transistors on each pixel for precise current control and, as such, the mask patterns for OLED displays are denser and finer than the patterns for the previous generation displays throughout the entire mask surface. It is therefore strongly demanded that mask patterns be produced with high fidelity and free of defect. To enable the production of a high quality LSPM in a short lead time, the manufacturers need a high-sensitivity high-speed mask blank inspection system that meets the requirement of advanced LSPMs. Lasertec has developed a large-size blank inspection system called LBIS, which achieves high sensitivity based on a laser-scattering technique. LBIS employs a high power laser as its inspection light source. LBIS's delivery optics, including a scanner and F-Theta scan lens, focus the light from the source linearly on the surface of the blank. Its specially-designed optics collect the light scattered by particles and defects generated during the manufacturing process, such as scratches, on the surface and guide it to photo multiplier tubes (PMTs) with high efficiency. Multiple PMTs are used on LBIS for the stable detection of scattered light, which may be distributed at various angles due to irregular shapes of defects. LBIS captures 0.3mμ PSL at a detection rate of over 99.5% with uniform sensitivity. Its inspection time is 20 minutes for a G8 blank and 35 minutes for G10. The differential interference contrast (DIC) microscope on the inspection head of LBIS captures high-contrast review images after inspection. The images are classified automatically.

  20. Complexity analysis on public transport networks of 97 large- and medium-sized cities in China

    Science.gov (United States)

    Tian, Zhanwei; Zhang, Zhuo; Wang, Hongfei; Ma, Li

    2018-04-01

    The traffic situation in Chinese urban areas is continuing to deteriorate. To make a better planning and designing of the public transport system, it is necessary to make profound research on the structure of urban public transport networks (PTNs). We investigate 97 large- and medium-sized cities’ PTNs in China, construct three types of network models — bus stop network, bus transit network and bus line network, then analyze the structural characteristics of them. It is revealed that bus stop network is small-world and scale-free, bus transit network and bus line network are both small-world. Betweenness centrality of each city’s PTN shows similar distribution pattern, although these networks’ size is various. When classifying cities according to the characteristics of PTNs or economic development level, the results are similar. It means that the development of cities’ economy and transport network has a strong correlation, PTN expands in a certain model with the development of economy.

  1. Technical trends of large-size photomasks for flat panel displays

    Science.gov (United States)

    Yoshida, Koichiro

    2017-06-01

    Currently, flat panel displays (FPDs) are one of the main parts for information technology devices and sets. From 1990's to 2000's, liquid crystal displays (LCDs) and plasma displays had been mainstream FPDs. In the middle of 2000's, demand of plasma displays declined and organic light emitting diodes (OLEDs) newly came into FPD market. And today, major technology of FPDs are LCDs and OLEDs. Especially for mobile devices, the penetration of OLEDs is remarkable. In FPDs panel production, photolithography is the key technology as same as LSI. Photomasks for FPDs are used not only as original master of circuit pattern, but also as a tool to form other functional structures of FPDs. Photomasks for FPDs are called as "Large Size Photomasks(LSPMs)", since the remarkable feature is " Size" which reaches over 1- meter square and over 100kg. In this report, we discuss three LSPMs technical topics with FPDs technical transition and trend. The first topics is upsizing of LSPMs, the second is the challenge for higher resolution patterning, and the last is "Multi-Tone Mask" for "Half -Tone Exposure".

  2. Resonant atom-field interaction in large-size coupled-cavity arrays

    International Nuclear Information System (INIS)

    Ciccarello, Francesco

    2011-01-01

    We consider an array of coupled cavities with staggered intercavity couplings, where each cavity mode interacts with an atom. In contrast to large-size arrays with uniform hopping rates where the atomic dynamics is known to be frozen in the strong-hopping regime, we show that resonant atom-field dynamics with significant energy exchange can occur in the case of staggered hopping rates even in the thermodynamic limit. This effect arises from the joint emergence of an energy gap in the free photonic dispersion relation and a discrete frequency at the gap's center. The latter corresponds to a bound normal mode stemming solely from the finiteness of the array length. Depending on which cavity is excited, either the atomic dynamics is frozen or a Jaynes-Cummings-like energy exchange is triggered between the bound photonic mode and its atomic analog. As these phenomena are effective with any number of cavities, they are prone to be experimentally observed even in small-size arrays.

  3. Comparison of caribou physical characteristics from Yukon and neighboring caribou herds

    Directory of Open Access Journals (Sweden)

    David A. Gauthier

    1986-06-01

    Full Text Available Data on seven external body measurements of caribou from six woodland and two barren-ground caribou herds from Yukon, Alaska, Alberta and British Columbia were compared. Comparisons between females in the fall and winter and mature males in the fall revealed that (1 barren-ground Porcupine caribou were consistently smaller than caribou from other herds, (2 British Columbia and Alberta caribou tended to be larger than Yukon caribou, or the Alaskan caribou studied, (3 central Yukon caribou were intermediate in body size, (4 no difference was found between Yukon «mountain» and «woodland» type caribou in body size, and (5 the barren-ground Fortymile caribou were more similar in physical characteristics to Yukon woodland or mountain caribou than to those of the barren-ground Porcupine herd. These data support Banfield's (1961 view of a gradient of decreasing physical size from the northern British Columbia — Alberta herds through the Yukon mountain or woodland herds to the northern barren-ground herds.

  4. The limits of weak selection and large population size in evolutionary game theory.

    Science.gov (United States)

    Sample, Christine; Allen, Benjamin

    2017-11-01

    Evolutionary game theory is a mathematical approach to studying how social behaviors evolve. In many recent works, evolutionary competition between strategies is modeled as a stochastic process in a finite population. In this context, two limits are both mathematically convenient and biologically relevant: weak selection and large population size. These limits can be combined in different ways, leading to potentially different results. We consider two orderings: the [Formula: see text] limit, in which weak selection is applied before the large population limit, and the [Formula: see text] limit, in which the order is reversed. Formal mathematical definitions of the [Formula: see text] and [Formula: see text] limits are provided. Applying these definitions to the Moran process of evolutionary game theory, we obtain asymptotic expressions for fixation probability and conditions for success in these limits. We find that the asymptotic expressions for fixation probability, and the conditions for a strategy to be favored over a neutral mutation, are different in the [Formula: see text] and [Formula: see text] limits. However, the ordering of limits does not affect the conditions for one strategy to be favored over another.

  5. Study of large size fiber reinforced cement containers for solid wastes from dismantling

    International Nuclear Information System (INIS)

    Jaouen, C.

    1990-01-01

    The production of large-sized metallic waste by dismantling operations, and the evolution of the specifications of the waste to be stored in the different European countries will create a need for large standard containers for the transport and final disposal of the corresponding waste. The research conducted during the 1984-1988 programme, supported by the Commission of European Communities, and based on a comparative study of high-grade concrete materials, reinforced with organic or metallic fibres, led to the development of a high performance container meeting international transport recommendations as well as French requirements for shallow-ground disposal. The material selected, consisting of high-performance mortar with metal fibre reinforcement, was the subject of an intensive programme of characterization tests conducted in close cooperation with LAFARGE Company, demonstrating the achievement of mechanical and physical properties comfortably above the regulatory requirements. The construction of an industrial prototype and the subsequent economic analysis served to guarantee the industrial feasibility and cost of this system, in which attempts were made to optimize the finished package product, including its closure system

  6. Herd-level risk factors for subclinical Salmonella infection in European finishing-pig herds

    DEFF Research Database (Denmark)

    Wong, Danilo Lo Fo; Dahl, J.; Stege, H.

    2004-01-01

    Our objective was to find herd factors associated with pigs testing seropositive for Salmonella. Data were collected from 359 finishing-pig herds in Germany, Denmark, Greece, The Netherlands and Sweden, between 1996 and 1998. Pigs fed non-pelleted feed (dry or wet) had 2- and 2.5-times lower odds...... recruiting from more than three supplier herds had three-times higher odds to test seropositive than pigs in herds which breed their own replacement stock or recruit from a maximum of three supplier herds....

  7. Forecasting metal prices: Do forecasters herd?

    DEFF Research Database (Denmark)

    Pierdzioch, C.; Rulke, J. C.; Stadtmann, G.

    2013-01-01

    We analyze more than 20,000 forecasts of nine metal prices at four different forecast horizons. We document that forecasts are heterogeneous and report that anti-herding appears to be a source of this heterogeneity. Forecaster anti-herding reflects strategic interactions among forecasters...

  8. Biosecurity in 121 Danish sow herds

    DEFF Research Database (Denmark)

    Boklund, Anette; Mortensen, Sten; Houe, H.

    2003-01-01

    Herds are under constant risk of introducing new pathogens from different sources. In this article we describe biosecurity practices in Danish sow herds. Between December 1, 1999 and February 29, 2000, 121 sow units were interviewed regarding biosecurity on the site. The questionnaire contained 6...

  9. Resolution 8.069/12. It approve the regulations for the large size structures installation, destined for wind power generation

    International Nuclear Information System (INIS)

    2012-01-01

    This resolution approve the regulations for the large size structures installation, destined to wind power generation. The objective of this rule is to regulate the urban conditions of the facilities and the environmental guarantees, safety and inhabitants wholesomeness

  10. Technology for Obtaining Large Size Complex Oxide Crystals for Experiments on Muon-Electron Conversion Registration in High Energy Physics

    Directory of Open Access Journals (Sweden)

    Gerasymov, Ya.

    2014-11-01

    Full Text Available Technological approaches for qualitative large size scintillation crystals growing based on rare-earth silicates are proposed. A method of iridium crucibles charging using eutectic phase instead of a oxyorthosilicate was developed.

  11. Body size evolution in an old insect order: No evidence for Cope's Rule in spite of fitness benefits of large size.

    Science.gov (United States)

    Waller, John T; Svensson, Erik I

    2017-09-01

    We integrate field data and phylogenetic comparative analyses to investigate causes of body size evolution and stasis in an old insect order: odonates ("dragonflies and damselflies"). Fossil evidence for "Cope's Rule" in odonates is weak or nonexistent since the last major extinction event 65 million years ago, yet selection studies show consistent positive selection for increased body size among adults. In particular, we find that large males in natural populations of the banded demoiselle (Calopteryx splendens) over several generations have consistent fitness benefits both in terms of survival and mating success. Additionally, there was no evidence for stabilizing or conflicting selection between fitness components within the adult life-stage. This lack of stabilizing selection during the adult life-stage was independently supported by a literature survey on different male and female fitness components from several odonate species. We did detect several significant body size shifts among extant taxa using comparative methods and a large new molecular phylogeny for odonates. We suggest that the lack of Cope's rule in odonates results from conflicting selection between fitness advantages of large adult size and costs of long larval development. We also discuss competing explanations for body size stasis in this insect group. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  12. Large increase in nest size linked to climate change: an indicator of life history, senescence and condition.

    Science.gov (United States)

    Møller, Anders Pape; Nielsen, Jan Tøttrup

    2015-11-01

    Many animals build extravagant nests that exceed the size required for successful reproduction. Large nests may signal the parenting ability of nest builders suggesting that nests may have a signaling function. In particular, many raptors build very large nests for their body size. We studied nest size in the goshawk Accipiter gentilis, which is a top predator throughout most of the Nearctic. Both males and females build nests, and males provision their females and offspring with food. Nest volume in the goshawk is almost three-fold larger than predicted from their body size. Nest size in the goshawk is highly variable and may reach more than 600 kg for a bird that weighs ca. 1 kg. While 8.5% of nests fell down, smaller nests fell down more often than large nests. There was a hump-shaped relationship between nest volume and female age, with a decline in nest volume late in life, as expected for senescence. Clutch size increased with nest volume. Nest volume increased during 1977-2014 in an accelerating fashion, linked to increasing spring temperature during April, when goshawks build and start reproduction. These findings are consistent with nest size being a reliable signal of parental ability, with large nest size signaling superior parenting ability and senescence, and also indicating climate warming.

  13. Cybele: a large size ion source of module construction for Tore-Supra injector

    International Nuclear Information System (INIS)

    Simonin, A.; Garibaldi, P.

    2005-01-01

    A 70 keV 40 A hydrogen beam injector has been developed at Cadarache for plasma diagnostic purpose (MSE diagnostic and Charge exchange) on the Tore-Supra Tokamak. This injector daily operates with a large size ions source (called Pagoda) which does not completely fulfill all the requirements necessary for the present experiment. As a consequence, the development of a new ion source (called Cybele) has been underway whose objective is to meet high proton rate (>80%), current density of 160 mA/cm 2 within 5% of uniformity on the whole extraction surface for long shot operation (from 1 to 100 s). Moreover, the main particularity of Cybele is the module construction concept: it is composed of five source modules vertically juxtaposed, with a special orientation which fits the curved extraction surface of the injector; this curvature ensures a geometrical focalization of the neutral beam 7 m downstream in the Tore-Supra chamber. Cybele will be tested first in positive ion production for the Tore-Supra injector, and afterward in negative ion production mode; its modular concept could be advantageous to ensure plasma uniformity on the large extraction surface (about 1 m 2 ) of the ITER neutral beam injector. A module prototype (called the Drift Source) has already been developed in the past and optimized in the laboratory both for positive and negative ion production, where it has met the ITER ion source requirements in terms of D-current density (200 A/m 2 ), source pressure (0.3 Pa), uniformity and arc efficiency (0.015 A D-/kW). (authors)

  14. Large explosive basaltic eruptions at Katla volcano, Iceland: Fragmentation, grain size and eruption dynamics

    Science.gov (United States)

    Schmith, Johanne; Höskuldsson, Ármann; Holm, Paul Martin; Larsen, Guðrún

    2018-04-01

    Katla volcano in Iceland produces hazardous large explosive basaltic eruptions on a regular basis, but very little quantitative data for future hazard assessments exist. Here details on fragmentation mechanism and eruption dynamics are derived from a study of deposit stratigraphy with detailed granulometry and grain morphology analysis, granulometric modeling, componentry and the new quantitative regularity index model of fragmentation mechanism. We show that magma/water interaction is important in the ash generation process, but to a variable extent. By investigating the large explosive basaltic eruptions from 1755 and 1625, we document that eruptions of similar size and magma geochemistry can have very different fragmentation dynamics. Our models show that fragmentation in the 1755 eruption was a combination of magmatic degassing and magma/water-interaction with the most magma/water-interaction at the beginning of the eruption. The fragmentation of the 1625 eruption was initially also a combination of both magmatic and phreatomagmatic processes, but magma/water-interaction diminished progressively during the later stages of the eruption. However, intense magma/water interaction was reintroduced during the final stages of the eruption dominating the fine fragmentation at the end. This detailed study of fragmentation changes documents that subglacial eruptions have highly variable interaction with the melt water showing that the amount and access to melt water changes significantly during eruptions. While it is often difficult to reconstruct the progression of eruptions that have no quantitative observational record, this study shows that integrating field observations and granulometry with the new regularity index can form a coherent model of eruption evolution.

  15. Strength and fatigue testing of large size wind turbines rotors. Vol. II: Full size natural vibration and static strength test, a reference case

    Energy Technology Data Exchange (ETDEWEB)

    Arias, F.; Soria, E.

    1996-12-01

    This report shows the methods and procedures selected to define a strength test for large size wind turbine, anyway in particular it application on a 500 kW blade and it results obtained in the test carried out in july of 1995 in Asinel`s test plant (Madrid). Henceforth, this project is designed in an abbreviate form whit the acronym SFAT. (Author)

  16. Strength and fatigue testing of large size wind turbines rotors. Volume II. Full size natural vibration and static strength test, a reference case

    International Nuclear Information System (INIS)

    Arias, F.; Soria, E.

    1996-01-01

    This report shows the methods and procedures selected to define a strength test for large size wind turbine, anyway in particularly it application on a 500 kW blade and it results obtained in the test carried out in july of 1995 in Asinel test plant (Madrid). Henceforth, this project is designed in an abbreviate form whit the acronym SFAT. (Author)

  17. Predation rate by wolves on the Porcupine caribou herd

    OpenAIRE

    Hayes, Robert D.; Russell, Donald E.

    2000-01-01

    Large migratory catibou {Rangifer tarandus) herds in the Arctic tend to be cyclic, and population trends are mainly driven by changes in forage or weather events, not by predation. We estimated daily kill rate by wolves on adult caribou in winter, then constructed a time and space dependent model to estimate annual wolf (Canis lupus) predation rate (P annual) on adult Porcupine caribou. Our model adjusts predation seasonally depending on caribou distribution: Pannual = SIGMAdaily* W *Ap(2)*Dp...

  18. A four year longitudinal sero-epidemiological study of bovine herpesvirus type-1 (BHV-1 in adult cattle in 107 unvaccinated herds in south west England

    Directory of Open Access Journals (Sweden)

    Ramirez-Villaescusa Ana M

    2009-01-01

    Full Text Available Abstract Background Bovine herpesvirus type-1 (BHV-1 is an important pathogen of cattle that presents with a variety of clinical signs, including the upper respiratory tract infection infectious bovine rhinotracheitis (IBR. A seroepidemiological study of BHV-1 antibodies was conducted in England from 2002 – 2004: 29,782 blood samples were taken from 15,736 cattle from 114 herds which were visited on up to three occasions. Antibody concentration was measured using a commercial ELISA. Farm management information was collected using an interview questionnaire, and herd size and cattle movements were obtained from the cattle tuberculosis testing database and the British Cattle Movement Service. Hierarchical statistical models were used to investigate associations between cattle and herd variables and the continuous outcome percentage positive (PP values from the ELISA test in unvaccinated herds. Results There were 7 vaccinated herds, all with at least one seropositive bovine. In unvaccinated herds 83.2% had at least one BHV-1 seropositive bovine, and the mean cattle and herd BHV-1 seroprevalence were 42.5% and 43.1% respectively. There were positive associations between PP value, age, herd size, presence of dairy cattle. Adult cattle in herds with grower cattle had lower PP values than those in herds without grower cattle. Purchased cattle had significantly lower PP values than homebred cattle, whereas cattle in herds that were totally restocked after the foot-and-mouth epidemic in 2001 had significantly higher PP values than those in continuously stocked herds. Samples taken in spring and summer had significantly lower PP values than those taken in winter, whereas those taken in autumn had significantly higher PP values than those taken in winter. The risks estimated from a logistic regression model with a binary outcome (seropositive yes/no were similar. Conclusion The prevalence of BHV-1 seropositivity in cattle and herds has increased since

  19. Prototyping a large field size IORT applicator for a mobile linear accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Janssen, Rogier W J; Dries, Wim J F [Catharina-Hospital Eindhoven, PO Box 1350, 5602 ZA, Eindhoven (Netherlands); Faddegon, Bruce A [University of California San Francisco Comprehensive Cancer Center, 1600 Divisadero Street, San Francisco, CA 94115-1708 (United States)], E-mail: rogier.janssen@mac.com

    2008-04-21

    The treatment of large tumors such as sarcomas with intra-operative radiotherapy using a Mobetron (registered) is often complicated because of the limited field size of the primary collimator and the available applicators (max Oe100 mm). To circumvent this limitation a prototype rectangular applicator of 80 x 150 mm{sup 2} was designed and built featuring an additional scattering foil located at the top of the applicator. Because of its proven accuracy in modeling linear accelerator components the design was based on the EGSnrc Monte Carlo simulation code BEAMnrc. First, the Mobetron (registered) treatment head was simulated both without an applicator and with a standard 100 mm applicator. Next, this model was used to design an applicator foil consisting of a rectangular Al base plate covering the whole beam and a pyramid of four stacked cylindrical slabs of different diameters centered on top of it. This foil was mounted on top of a plain rectangular Al tube. A prototype was built and tested with diode dosimetry in a water tank. Here, the prototype showed clinically acceptable 80 x 150 mm{sup 2} dose distributions for 4 MeV, 6 MeV and 9 MeV, obviating the use of complicated multiple irradiations with abutting field techniques. In addition, the measurements agreed well with the MC simulations, typically within 2%/1 mm.

  20. Prototyping a large field size IORT applicator for a mobile linear accelerator

    International Nuclear Information System (INIS)

    Janssen, Rogier W J; Dries, Wim J F; Faddegon, Bruce A

    2008-01-01

    The treatment of large tumors such as sarcomas with intra-operative radiotherapy using a Mobetron (registered) is often complicated because of the limited field size of the primary collimator and the available applicators (max Oe100 mm). To circumvent this limitation a prototype rectangular applicator of 80 x 150 mm 2 was designed and built featuring an additional scattering foil located at the top of the applicator. Because of its proven accuracy in modeling linear accelerator components the design was based on the EGSnrc Monte Carlo simulation code BEAMnrc. First, the Mobetron (registered) treatment head was simulated both without an applicator and with a standard 100 mm applicator. Next, this model was used to design an applicator foil consisting of a rectangular Al base plate covering the whole beam and a pyramid of four stacked cylindrical slabs of different diameters centered on top of it. This foil was mounted on top of a plain rectangular Al tube. A prototype was built and tested with diode dosimetry in a water tank. Here, the prototype showed clinically acceptable 80 x 150 mm 2 dose distributions for 4 MeV, 6 MeV and 9 MeV, obviating the use of complicated multiple irradiations with abutting field techniques. In addition, the measurements agreed well with the MC simulations, typically within 2%/1 mm

  1. Preferential enrichment of large-sized very low density lipoprotein populations with transferred cholesteryl esters

    International Nuclear Information System (INIS)

    Eisenberg, S.

    1985-01-01

    The effect of lipid transfer proteins on the exchange and transfer of cholesteryl esters from rat plasma HDL2 to human very low (VLDL) and low density (LDL) lipoprotein populations was studied. The use of a combination of radiochemical and chemical methods allowed separate assessment of [ 3 H]cholesteryl ester exchange and of cholesteryl ester transfer. VLDL-I was the preferred acceptor for transferred cholesteryl esters, followed by VLDL-II and VLDL-III. LDL did not acquire cholesteryl esters. The contribution of exchange of [ 3 H]cholesteryl esters to total transfer was highest for LDL and decreased in reverse order along the VLDL density range. Inactivation of lecithin: cholesterol acyltransferase (LCAT) and heating the HDL2 for 60 min at 56 degrees C accelerated transfer and exchange of [ 3 H]cholesteryl esters. Addition of lipid transfer proteins increased cholesterol esterification in all systems. The data demonstrate that large-sized, triglyceride-rich VLDL particles are preferred acceptors for transferred cholesteryl esters. It is suggested that enrichment of very low density lipoproteins with cholesteryl esters reflects the triglyceride content of the particles

  2. Investigation of Low-Cost Surface Processing Techniques for Large-Size Multicrystalline Silicon Solar Cells

    Directory of Open Access Journals (Sweden)

    Yuang-Tung Cheng

    2010-01-01

    Full Text Available The subject of the present work is to develop a simple and effective method of enhancing conversion efficiency in large-size solar cells using multicrystalline silicon (mc-Si wafer. In this work, industrial-type mc-Si solar cells with area of 125×125 mm2 were acid etched to produce simultaneously POCl3 emitters and silicon nitride deposition by plasma-enhanced chemical vapor deposited (PECVD. The study of surface morphology and reflectivity of different mc-Si etched surfaces has also been discussed in this research. Using our optimal acid etching solution ratio, we are able to fabricate mc-Si solar cells of 16.34% conversion efficiency with double layers silicon nitride (Si3N4 coating. From our experiment, we find that depositing double layers silicon nitride coating on mc-Si solar cells can get the optimal performance parameters. Open circuit (Voc is 616 mV, short circuit current (Jsc is 34.1 mA/cm2, and minority carrier diffusion length is 474.16 μm. The isotropic texturing and silicon nitride layers coating approach contribute to lowering cost and achieving high efficiency in mass production.

  3. Reparation and validation of a large size dried spike: Batch SAL-9951

    International Nuclear Information System (INIS)

    Doubek, N.; Jammet, G.; Zoigner, A.

    1991-02-01

    To determine uranium and plutonium concentration using isotope dilution mass spectrometry, weighed aliquands of a synthetic mixture containing about 2mg of Pu (with a 239 Pu abundance of about 98%) and 37mg of U (with a 235 U enrichment of about 19%) have been prepared by the IAEA-SAL and verified by three analytical laboratories: NMCC-SAL, OEFZS, IAEA-SAL; they will be used to spike samples of concentrated spent fuel solutions with a high burnup and a low 235 U enrichment. Certified Reference Materials Pu-NBL-126, natural U-NBL-112A and 93% enriched U-NBL-116 were used to prepare a stock solution containing about 3.2 mg/ml of Pu and 64.3 mg/ml of 18.7% enriched U. Before shipment to the Reprocessing Plant, aliquands of the stock solution are dried to give Large Size Dried (LSD) Spikes which resist shocks encountered during transportation, so that they can readily be recovered quantitatively at the plant. This paper describes the preparation and the validation of a fifth batch of LSD-spike which is intended to be used as a common spike by the plant operator, the national and the IAEA inspectorates. 7 refs, 6 tabs

  4. Hydrophobic polymers modification of mesoporous silica with large pore size for drug release

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Shenmin, E-mail: smzhu@sjtu.edu.c [Shanghai Jiao Tong University, State Key Lab of Metal Matrix Composites (China); Zhang Di; Yang Na [Fudan University, Ministry of Education, Key Lab of Molecular Engineering of Polymers (China)

    2009-04-15

    Mesostructure cellular foam (MCF) materials were modified with hydrophobic polyisoprene (PI) through free radical polymerization in the pores network, and the resulting materials (MCF-PI) were investigated as matrices for drug storage. The successful synthesis of PI inside MCF was characterized by Fourier transform infrared (FT-IR), hydrogen nuclear magnetic resonance ({sup 1}H NMR), X-ray diffraction patterns (XRD) and nitrogen adsorption/desorption measurements. It was interesting to find the resultant system held a relatively large pore size (19.5 nm) and pore volume (1.02 cm{sup 3} g{sup -1}), which would benefit for drug storage. Ibuprofen (IBU) and vancomycin were selected as model drugs and loaded onto unmodified MCF and modified MCF (MCF-PI). The adsorption capacities of these model drugs on MCF-PI were observed increase as compared to that of on pure MCF, due to the trap effects induced by polyisoprene chains inside the pores. The delivery system of MCF-PI was found to be more favorable for the adsorption of IBU (31 wt%, IBU/silica), possibly attributing to the hydrophobic interaction between IBU and PI formed on the internal surface of MCF matrix. The release of drug through the porous network was investigated by measuring uptake and release of IBU.

  5. Measurement of the thickness of the sprayed nickel coatings on large-sized cast iron products

    Directory of Open Access Journals (Sweden)

    В. А. Сясько

    2016-11-01

    Full Text Available Modern industries increasingly use automatic spraying of heat-resistant Nickel  coating with a thickness  of      T = 1-3 mm for large-size parts made of cast iron with nodular graphite. The process of coating application is characterized by time-dependent behavior of its relative magnetic permeability, μс , that is a function of relaxation time, which can be as long as 24 hours, and by μс deviation from point to point on the surface. Aspects of eddy-current phase method for measuring the T value are considered. The structure of four- winding eddy current transformer transducers is described and results of calculation and optimization of their parameters are presented. The influence of controlled and interfering parameters is considered. Based  on the above results, a two-channel combined transducer is developed  providing measurement  error  of ΔТ ≤ ±(0.03T + 0.02 mm  in the shop environment in the process of coating application and in the final product check. Results of tests on reference specimens and of application in production processes are presented.

  6. Key Supplier Relationship Management: The Case of Croatian Medium-Sized and Large Manufacturing Companies

    Directory of Open Access Journals (Sweden)

    Dario Miočević

    2011-06-01

    Full Text Available The key supplier relationship management represents a vital organizational process. Companies should pay attention not only to managing customer relationships but also to managing relationships with suppliers in order to perform well. They should identify the extent to which a certain supplier adds value through the procurement process. In this line of reasoning, both theory and practice make a distinction between strategic (key and non-strategic (transactional suppliers. By employing the segmentation of the supply market, companies balance their supplier portfolio and are capable of identifying the key suppliers. They can also develop specific programs and initiatives that are aimed at preserving these relationships. In the empirical part of the paper, a survey was conducted on a sample of 123 medium-sized and large Croatian manufacturing companies. The structural model involving the relationship between the key supplier relationship management and value-oriented purchasing was tested. The results indicate that there is a statistically direct, positive and significant relationship between these two constructs. Likewise, the results stress that a theoretical conceptualization and operationalization of the key supplier relationship management construct is both valid and justified. Finally, the theoretical and practical implications and limitations of this study are offered.

  7. Trees of unusual size: biased inference of early bursts from large molecular phylogenies.

    Directory of Open Access Journals (Sweden)

    Matthew W Pennell

    Full Text Available An early burst of speciation followed by a subsequent slowdown in the rate of diversification is commonly inferred from molecular phylogenies. This pattern is consistent with some verbal theory of ecological opportunity and adaptive radiations. One often-overlooked source of bias in these studies is that of sampling at the level of whole clades, as researchers tend to choose large, speciose clades to study. In this paper, we investigate the performance of common methods across the distribution of clade sizes that can be generated by a constant-rate birth-death process. Clades which are larger than expected for a given constant-rate branching process tend to show a pattern of an early burst even when both speciation and extinction rates are constant through time. All methods evaluated were susceptible to detecting this false signature when extinction was low. Under moderate extinction, both the [Formula: see text]-statistic and diversity-dependent models did not detect such a slowdown but only because the signature of a slowdown was masked by subsequent extinction. Some models which estimate time-varying speciation rates are able to detect early bursts under higher extinction rates, but are extremely prone to sampling bias. We suggest that examining clades in isolation may result in spurious inferences that rates of diversification have changed through time.

  8. Fabrication of large size alginate beads for three-dimensional cell-cluster culture

    Science.gov (United States)

    Zhang, Zhengtao; Ruan, Meilin; Liu, Hongni; Cao, Yiping; He, Rongxiang

    2017-08-01

    We fabricated large size alginate beads using a simple microfluidic device under a co-axial injection regime. This device was made by PDMS casting with a mold formed by small diameter metal and polytetrafluorothylene tubes. Droplets of 2% sodium alginate were generated in soybean oil through the device and then cross-linked in a 2% CaCl2 solution, which was mixed tween80 with at a concentration of 0.4 to 40% (w/v). Our results showed that the morphology of the produced alginate beads strongly depends on the tween80 concentration. With the increase of concentration of tween80, the shape of the alginate beads varied from semi-spherical to tailed-spherical, due to the decrease of interface tension between oil and cross-link solution. To access the biocompatibility of the approach, MCF-7 cells were cultured with the alginate beads, showing the formation of cancer cells clusters which might be useful for future studies.

  9. Preparation and provisional validation of a large size dried spike: Batch SAL-9934

    International Nuclear Information System (INIS)

    Jammet, G.; Zoigner, A.; Doubek, N.; Aigner, H.; Deron, S.; Bagliano, G.

    1990-05-01

    To determine uranium and plutonium concentration using isotope dilution mass spectrometry, weighed aliquands of a synthetic mixture containing about 2 mg of Pu (with a 239 Pu abundance of about 98%) and 40 mg of U (with a 235 U enrichment of about 19%) have been prepared and verified by SAL to be used to spike samples of concentrated spent fuel solutions with a high burn-up and a low 235 U enrichment. Certified Reference Materials Pu-NBL-126, natural U-NBS-960 and 93% enriched U-NBL-116 were used to prepare a stock solution containing 3.2 mg/ml of Pu and 64.3 mg/ml of 18.8% enriched U. Before shipment to the Reprocessing Plant, aliquands of the stock solution are dried to give Large Size Dried (LSD) Spikes which resist shocks encountered during transportation, so that they can readily be recovered quantitatively at the plant. This paper describes the preparation and the validation of a third batch of LSD-Spike which is intended to be used as a common spike by the plant operator, the national and the IAEA inspectorates. 6 refs, 6 tabs

  10. Fluorosis in a dairy herd

    Energy Technology Data Exchange (ETDEWEB)

    Jones, W G

    1972-04-29

    Investigation of a high incidence of hip arthritis in a herd of Ayrshires resulted in the discovery of abnormal levels of fluorine in samples of bone. Suspicion of fluorosis was not aroused earlier as the area is not contaminated by industrial fall-out. In addition, many affected animals had no lesions in their teeth; this was because their dentition was complete before ingesting fluorine from a mineral supplement. Only cows receiving toxic levels of fluorine during their first lactation showed lesions, and these were confined to the fourth pair of incisors. Two metabolic profile tests were caried out to establish that the input-output balance in the main metabolites was normal. Analysis of various constituents of the diet revealed significant levels of fluorine in the mineral supplement only. Arthritis was the most prominent feature. This led to debility, with loss of milk and carcase value. Confirmation of fluorosis was obtained by analysis of bone and urine.

  11. Large-size deployable construction heated by solar irradiation in free space

    Science.gov (United States)

    Pestrenina, Irena; Kondyurin, Alexey; Pestrenin, Valery; Kashin, Nickolay; Naymushin, Alexey

    Large-size deployable construction in free space with subsequent direct curing was invented more than fifteen years ago (Briskman et al., 1997 and Kondyurin, 1998). It caused a lot of scientific problems, one of which is a possibility to use the solar energy for initiation of the curing reaction. This paper is devoted to investigate the curing process under sun irradiation during a space flight in Earth orbits. A rotation of the construction is considered. This motion can provide an optimal temperature distribution in the construction that is required for the polymerization reaction. The cylindrical construction of 80 m length with two hemispherical ends of 10 m radius is considered. The wall of the construction of 10 mm carbon fibers/epoxy matrix composite is irradiated by heat flux from the sun and radiates heat from the external surface by the Stefan- Boltzmann law. A stage of polymerization reaction is calculated as a function of temperature/time based on the laboratory experiments with certified composite materials for space exploitation. The curing kinetics of the composite is calculated for different inclination Low Earth Orbits (300 km altitude) and Geostationary Earth Orbit (40000 km altitude). The results show that • the curing process depends strongly on the Earth orbit and the rotation of the construction; • the optimal flight orbit and rotation can be found to provide the thermal regime that is sufficient for the complete curing of the considered construction. The study is supported by RFBR grant No.12-08-00970-a. 1. Briskman V., A.Kondyurin, K.Kostarev, V.Leontyev, M.Levkovich, A.Mashinsky, G.Nechitailo, T.Yudina, Polymerization in microgravity as a new process in space technology, Paper No IAA-97-IAA.12.1.07, 48th International Astronautical Congress, October 6-10, 1997, Turin Italy. 2. Kondyurin A.V., Building the shells of large space stations by the polymerisation of epoxy composites in open space, Int. Polymer Sci. and Technol., v.25, N4

  12. An epidemiological investigation of the early phase of the porcine epidemic diarrhea (PED) outbreak in Canadian swine herds in 2014: A case-control study.

    Science.gov (United States)

    Perri, Amanda M; Poljak, Zvonimir; Dewey, Cate; Harding, John C S; O'Sullivan, Terri L

    2018-02-01

    The first case of porcine epidemic diarrhea (PED) in Canada was diagnosed in January 2014 in Ontario, approximately 9 months after PED emerged in the United States. An early investigation of the Canadian outbreak suspected that the probable source of the virus was contaminated feed. The objective of this study was to evaluate the role of feed and other possible factors in the early phase of the PED outbreak in Canadian swine herds. The study period of interest for this case-control study was January 22nd to March 1st, 2014. A case herd was defined as a swine herd with a confirmed positive laboratory diagnostic test (RT-PCR) results for PED virus, along with pigs exhibiting typical clinical signs at the herd level during the study period. A questionnaire was administered to participating producers from the 22 Canadian swine herds enrolled (n = 9 case and n = 13 control herds). Case herd producers were asked to provide information from the initial day of onset of clinical signs and 30 days prior to that day. Control herds were matched to a case herd on the basis of province, herd type and approximate size. The period of interest for a control herd was matched to the initial day of clinical signs of PED for the case herd, along with the 30 days prior to this day. The questionnaire questions focused on herd demographics, biosecurity protocols, live animal movements onto and off sites, deadstock movements, feed and people movements for both the case and control herds. The questionnaire for control herds were based on their matched case's period of interest, and together with case herds formed a matched stratum. Multivariable exact conditional logistic regression and mixed multivariable logistic regression models, with the matched stratum as a random effect, were used to assess the association between various risk factors and the odds of PED introduction into a herd. After adjusting for biosecurity practices, the odds of a PED occurrence was 38.1 (95% CI: 2

  13. The research of the quantitative prediction of the deposits concentrated regions of the large and super-large sized mineral deposits in China

    International Nuclear Information System (INIS)

    Zhao Zhenyu; Wang Shicheng

    2003-01-01

    By the general theory and method of mineral resources prognosis of synthetic information, the locative and quantitative prediction of the large and super-large sized mineral deposits of solid resources of 1 : 5,000,000 are developed in china. The deposit concentrated regions is model unit, the anomaly concentrated regions is prediction unit. The mineral prognosis of synthetic information is developed on GIS platform. The technical route and work method of looking for the large and super-large sized mineral resources and basic principle of compiling attribute table of the variables and the response variables are mentioned. In research of prediction of resources quantity, the locative and quantitative prediction are processed by separately the quantification theory Ⅲ and the corresponding characteristic analysis, two methods are compared. It is very important for resources prediction of western ten provinces in china, it is helpful. (authors)

  14. Design of large size segmented GEM foils and Drift PCB for CBM MUCH

    International Nuclear Information System (INIS)

    Saini, J.; Dubey, A.K.; Chattopadhyay, S.

    2016-01-01

    Triple GEM (Gas Electron Multiplier), sector shaped detectors will be used for Muon tracking in the Compressed Baryonic Matter (CBM) experiment at Anti-proton Ion Research (FAIR) facility at Darmstadt, Germany. The sizes of the detectors modules in the Muon Chambers (MUCH) are of the order of 1 meter with active area of about 75cms. Progressive pad geometry is chosen for the readout from these detectors. In construction of these chambers, three GEM foils are stacked on top of each other in a 3/2/2/2 gap configuration. The GEM foils are double layered copper clad 50μm thin Kapton foil. Each GEM foil has millions of holes on it. Foils of large surface area are prone to damages due to discharges owing to the high capacitance of the foil. Hence, these foils have their top surfaces divided into segments of about 100 sq.cm. Further segmentation may be necessary when there are high rate requirements, as in the case of CBM. For the GEM foils of CBM MUCH, a 24 segment layout has been adopted. Short-circuit in any of the GEM-holes will make entire foil un-usable. To reduce such occurrences, segment to segment isolation using opto-coupler in series with the GEM-foil segments has been introduced. Hence, a novel design for GEM chamber drift-PCB and foils has been made. In this scheme, each segment is powered and controlled individually. At the same time, the design takes into account, the space constraints, not only in x-y plane, but also in the z, due to compact assembly of MUCH detector layers

  15. Evaluation of milk yield losses associated with Salmonella antibodies in bulk tank milk in bovine dairy herds.

    Science.gov (United States)

    Nielsen, T D; Green, L E; Kudahl, A B; Østergaard, S; Nielsen, L R

    2012-09-01

    The effect of Salmonella on milk production is not well established in cattle. The objective of this study was to investigate whether introduction of Salmonella into dairy cattle herds was associated with reduced milk yield and determine the duration of any such effect. Longitudinal data from 2005 through 2009 were used, with data from 12 mo before until 18 mo after the estimated date of infection. Twenty-eight case herds were selected based on an increase in the level of Salmonella-specific antibodies in bulk-tank milk from levels consistently energy-corrected milk (ECM)/cow were used to investigate daily milk yield before and after the estimated herd infection date for cows in parities 1, 2, and 3+. Control herds were used to evaluate whether the effects in the case herds could be reproduced in herds without Salmonella infection. Herd size, days in milk, somatic cell count, season, and year were included in the models. Yield in first-parity cows was reduced by a mean of 1.4 kg (95% confidence interval: 0.5 to 2.3) of ECM/cow per day from 7 to 15 mo after the estimated herd infection date, compared with that of first-parity cows in the same herds in the 12 mo before the estimated herd infection date. Yield for parity 3+ cows was reduced by a mean of 3.0 kg (95% confidence interval: 1.3 to 4.8) of ECM/cow per day from 7 to 15 mo after herd infection compared with that of parity 3+ cows in the 12 mo before the estimated herd infection. We observed minor differences in yield in second-parity cows before and after herd infection and observed no difference between cows in control herds before and after the simulated infection date. Milk yield decreased significantly in affected herds and the reduction was detectable several months after the increase in bulk tank milk Salmonella antibodies. It took more than 1 yr for milk yield to return to preinfection levels. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  16. Growth of large-size-two-dimensional crystalline pentacene grains for high performance organic thin film transistors

    Directory of Open Access Journals (Sweden)

    Chuan Du

    2012-06-01

    Full Text Available New approach is presented for growth of pentacene crystalline thin film with large grain size. Modification of dielectric surfaces using a monolayer of small molecule results in the formation of pentacene thin films with well ordered large crystalline domain structures. This suggests that pentacene molecules may have significantly large diffusion constant on the modified surface. An average hole mobility about 1.52 cm2/Vs of pentacene based organic thin film transistors (OTFTs is achieved with good reproducibility.

  17. Gastrointestinal nematodes and anthelmintic resistance in Danish goat herds

    DEFF Research Database (Denmark)

    Holm, Signe A.; Sørensen, Camilla; Thamsborg, Stig M.

    2014-01-01

    The prevalence of gastrointestinal parasites in Danish goats and the presence of anthelmintic resistance (AR) in 10 selected herds were investigated during April-September 2012. All Danish herds (n = 137) with 10 or more adult goats were invited to participate, and of these 27 herds met......, resistance to the most commonly used anthelmintics is widespread in larger goat herds throughout Denmark....

  18. Temporal trends in reproductive performance in Irish dairy herds and associated risk factors

    Directory of Open Access Journals (Sweden)

    Mee John F

    2004-03-01

    Full Text Available Irish dairy herd fertility has been declining since the 1980s. The extent, nature and causes of this decline in fertility and the current status of Irish dairy herd fertility were described. An increase in calving interval of approximately one day per year has been recorded. The principal components of this trend have been an increased incidence of postpartum endocrinopathies, reduced expression of oestrus and a fall in conception rate. Both submission rate and calving-to-service interval have increased slightly over time. Significant risk factors associated with these trends have been strain substitution within the Holstein-Friesian breed and single trait selection for milk production. Critically, these changes have been reflected in loss of body condition. Contributory factors included increased herd size and possibly increased use of DIYAI. The most recent Irish study showed that 48% of cows conceived to first service and 14% of cows were not pregnant at the end of the industry-average 15-week spring breeding season. However, the top quartile of herds achieved a first-service conception rate of 59%, illustrating the wide variation between herds. These phenotypic trends were attributed to both genetic and environmental factors and their interactions. Recent Irish dairy herd fertility performance falls short of the targets set for seasonal compact calving.

  19. Gastro-oesophageal reflux in large-sized, deep-chested versus small-sized, barrel-chested dogs undergoing spinal surgery in sternal recumbency.

    Science.gov (United States)

    Anagnostou, Tilemahos L; Kazakos, George M; Savvas, Ioannis; Kostakis, Charalampos; Papadopoulou, Paraskevi

    2017-01-01

    The aim of this study was to investigate whether an increased frequency of gastro-oesophageal reflux (GOR) is more common in large-sized, deep-chested dogs undergoing spinal surgery in sternal recumbency than in small-sized, barrelchested dogs. Prospective, cohort study. Nineteen small-sized, barrel-chested dogs (group B) and 26 large-sized, deep-chested dogs (group D). All animals were premedicated with intramuscular (IM) acepromazine (0.05 mg kg -1 ) and pethidine (3 mg kg -1 ) IM. Anaesthesia was induced with intravenous sodium thiopental and maintained with halothane in oxygen. Lower oesophageal pH was monitored continuously after induction of anaesthesia. Gastro-oesophageal reflux was considered to have occurred whenever pH values > 7.5 or < 4 were recorded. If GOR was detected during anaesthesia, measures were taken to avoid aspiration of gastric contents into the lungs and to prevent the development of oesophagitis/oesophageal stricture. The frequency of GOR during anaesthesia was significantly higher in group D (6/26 dogs; 23.07%) than in group B (0/19 dogs; 0%) (p = 0.032). Signs indicative of aspiration pneumonia, oesophagitis or oesophageal stricture were not reported in any of the GOR cases. In large-sized, deep-chested dogs undergoing spinal surgery in sternal recumbency, it would seem prudent to consider measures aimed at preventing GOR and its potentially devastating consequences (oesophagitis/oesophageal stricture, aspiration pneumonia). Copyright © 2016 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.

  20. Size and shape characteristics of drumlins, derived from a large sample, and associated scaling laws

    Science.gov (United States)

    Clark, Chris D.; Hughes, Anna L. C.; Greenwood, Sarah L.; Spagnolo, Matteo; Ng, Felix S. L.

    2009-04-01

    Ice sheets flowing across a sedimentary bed usually produce a landscape of blister-like landforms streamlined in the direction of the ice flow and with each bump of the order of 10 2 to 10 3 m in length and 10 1 m in relief. Such landforms, known as drumlins, have mystified investigators for over a hundred years. A satisfactory explanation for their formation, and thus an appreciation of their glaciological significance, has remained elusive. A recent advance has been in numerical modelling of the land-forming process. In anticipation of future modelling endeavours, this paper is motivated by the requirement for robust data on drumlin size and shape for model testing. From a systematic programme of drumlin mapping from digital elevation models and satellite images of Britain and Ireland, we used a geographic information system to compile a range of statistics on length L, width W, and elongation ratio E (where E = L/ W) for a large sample. Mean L, is found to be 629 m ( n = 58,983), mean W is 209 m and mean E is 2.9 ( n = 37,043). Most drumlins are between 250 and 1000 metres in length; between 120 and 300 metres in width; and between 1.7 and 4.1 times as long as they are wide. Analysis of such data and plots of drumlin width against length reveals some new insights. All frequency distributions are unimodal from which we infer that the geomorphological label of 'drumlin' is fair in that this is a true single population of landforms, rather than an amalgam of different landform types. Drumlin size shows a clear minimum bound of around 100 m (horizontal). Maybe drumlins are generated at many scales and this is the minimum, or this value may be an indication of the fundamental scale of bump generation ('proto-drumlins') prior to them growing and elongating. A relationship between drumlin width and length is found (with r2 = 0.48) and that is approximately W = 7 L 1/2 when measured in metres. A surprising and sharply-defined line bounds the data cloud plotted in E- W

  1. Within-herd prevalence of Salmonella Dublin in endemically infected dairy herds

    DEFF Research Database (Denmark)

    Nielsen, Liza Rosenbaum

    2013-01-01

    SUMMARY In this study within-herd prevalence of Salmonella Dublin was investigated in three age groups (calves, young stock, adult cows) during five herd visits at 3-month intervals of 14 endemically infected dairy herds. A total of 10162 paired faecal cultures and antibody measurements were used...... stock and adult cows than in calves. Hierarchical mixed-model results showed that seroprevalence was associated with the bacteriological status in calves and cows, but not in young stock. These results can be used to develop and validate theoretical infection dynamics models and to design effective...... control programmes for Salmonella Dublin in dairy herds....

  2. Safety requirements and options for a large size fast neutron reactor

    International Nuclear Information System (INIS)

    Cogne, F.; Megy, J.; Robert, E.; Benmergui, A.; Villeneuve, J.

    1977-01-01

    Starting from the experience gained in the safety evaluation of the PHENIX reactor, and from results already obtained in the safety studies on fast neutron reactors, the French regulatory bodies have defined since 1973 what could be the requirements and the recommendations in the matter of safety for the first large size ''prototype'' fast neutron power plant of 1200 MWe. Those requirements and recommendations, while not being compulsory due to the evolution of this type of reactors, will be used as a basis for the technical regulation that will be established in France in this field. They define particularly the care to be taken in the following areas which are essential for safety: the protection systems, the primary coolant system, the prevention of accidents at the core level, the measures to be taken with regard to the whole core accident and to the containment, the protection against sodium fires, and the design as a function of external aggressions. In applying these recommendations, the CREYS-MALVILLE plant designers have tried to achieve redundancy in the safety related systems and have justified the safety of the design with regard to the various involved phenomena. In particular, the extensive research made at the levels of the fuel and of the core instrumentation makes it possible to achieve the best defence to avoid the development of core accidents. The overall examination of the measures taken, from the standpoint of prevention and surveyance as well as from the standpoint of means of action led the French regulatory bodies to propose the construction permit of the CREYS MALVILLE plant, provided that additional examinations by the regulatory bodies be made during the construction of the plant on some technological aspects not fully clarified at the authorization time. The conservatism of the corresponding requirements should be demonstrated prior to the commissioning of the power plant. To pursue a programme on reactors of this type, or even more

  3. THE HERD BEHAVIOR AND THE FINANCIAL INSTABILITY

    Directory of Open Access Journals (Sweden)

    CRISTIAN IONESCU

    2012-01-01

    Full Text Available Given the international financial situation of the last 50 years, and considering the complexity and severity of the financial crises, it is important to study the episodes of financial instability, and especially to understand both operating mechanisms and propagation mechanisms. One endogenous mechanism of financial instability is the herd behavior, which may increase the volatility and the amplitude of any sub-part of the financial system. This paper aims to analyze this phenomenon, considering the behavior of the financial market participants, the role of information in the making decisions process, banking responsibility regarding the herd behavior. The paper also illustrates two examples of herd behavior (run bank and the "too many to fail" problem, and presents three herding measures, in an attempt to achieve a quantitative analysis of the phenomenon, besides the qualitative analysis exposed above.

  4. Effect of crowd size on patient volume at a large, multipurpose, indoor stadium.

    Science.gov (United States)

    De Lorenzo, R A; Gray, B C; Bennett, P C; Lamparella, V J

    1989-01-01

    A prediction of patient volume expected at "mass gatherings" is desirable in order to provide optimal on-site emergency medical care. While several methods of predicting patient loads have been suggested, a reliable technique has not been established. This study examines the frequency of medical emergencies at the Syracuse University Carrier Dome, a 50,500-seat indoor stadium. Patient volume and level of care at collegiate basketball and football games as well as rock concerts, over a 7-year period were examined and tabulated. This information was analyzed using simple regression and nonparametric statistical methods to determine level of correlation between crowd size and patient volume. These analyses demonstrated no statistically significant increase in patient volume for increasing crowd size for basketball and football events. There was a small but statistically significant increase in patient volume for increasing crowd size for concerts. A comparison of similar crowd size for each of the three events showed that patient frequency is greatest for concerts and smallest for basketball. The study suggests that crowd size alone has only a minor influence on patient volume at any given event. Structuring medical services based solely on expected crowd size and not considering other influences such as event type and duration may give poor results.

  5. When bigger is not better: selection against large size, high condition and fast growth in juvenile lemon sharks.

    Science.gov (United States)

    Dibattista, J D; Feldheim, K A; Gruber, S H; Hendry, A P

    2007-01-01

    Selection acting on large marine vertebrates may be qualitatively different from that acting on terrestrial or freshwater organisms, but logistical constraints have thus far precluded selection estimates for the former. We overcame these constraints by exhaustively sampling and repeatedly recapturing individuals in six cohorts of juvenile lemon sharks (450 age-0 and 255 age-1 fish) at an enclosed nursery site (Bimini, Bahamas). Data on individual size, condition factor, growth rate and inter-annual survival were used to test the 'bigger is better', 'fatter is better' and 'faster is better' hypotheses of life-history theory. For age-0 sharks, selection on all measured traits was weak, and generally acted against large size and high condition. For age-1 sharks, selection was much stronger, and consistently acted against large size and fast growth. These results suggest that selective pressures at Bimini may be constraining the evolution of large size and fast growth, an observation that fits well with the observed small size and low growth rate of juveniles at this site. Our results support those of some other recent studies in suggesting that bigger/fatter/faster is not always better, and may often be worse.

  6. Prey size and availability limits maximum size of rainbow trout in a large tailwater: insights from a drift-foraging bioenergetics model

    Science.gov (United States)

    Dodrill, Michael J.; Yackulic, Charles B.; Kennedy, Theodore A.; Haye, John W

    2016-01-01

    The cold and clear water conditions present below many large dams create ideal conditions for the development of economically important salmonid fisheries. Many of these tailwater fisheries have experienced declines in the abundance and condition of large trout species, yet the causes of these declines remain uncertain. Here, we develop, assess, and apply a drift-foraging bioenergetics model to identify the factors limiting rainbow trout (Oncorhynchus mykiss) growth in a large tailwater. We explored the relative importance of temperature, prey quantity, and prey size by constructing scenarios where these variables, both singly and in combination, were altered. Predicted growth matched empirical mass-at-age estimates, particularly for younger ages, demonstrating that the model accurately describes how current temperature and prey conditions interact to determine rainbow trout growth. Modeling scenarios that artificially inflated prey size and abundance demonstrate that rainbow trout growth is limited by the scarcity of large prey items and overall prey availability. For example, shifting 10% of the prey biomass to the 13 mm (large) length class, without increasing overall prey biomass, increased lifetime maximum mass of rainbow trout by 88%. Additionally, warmer temperatures resulted in lower predicted growth at current and lower levels of prey availability; however, growth was similar across all temperatures at higher levels of prey availability. Climate change will likely alter flow and temperature regimes in large rivers with corresponding changes to invertebrate prey resources used by fish. Broader application of drift-foraging bioenergetics models to build a mechanistic understanding of how changes to habitat conditions and prey resources affect growth of salmonids will benefit management of tailwater fisheries.

  7. A comparison of workplace safety perceptions among financial decision-makers of medium- vs. large-size companies.

    Science.gov (United States)

    Huang, Yueng-Hsiang; Leamon, Tom B; Courtney, Theodore K; Chen, Peter Y; DeArmond, Sarah

    2011-01-01

    This study, through a random national survey in the U.S., explored how corporate financial decision-makers perceive important workplace safety issues as a function of the size of the company for which they worked (medium- vs. large-size companies). Telephone surveys were conducted with 404 U.S. corporate financial decision-makers: 203 from medium-size companies and 201 from large companies. Results showed that the patterns of responding for participants from medium- and large-size companies were somewhat similar. The top-rated safety priorities in resource allocation reported by participants from both groups were overexertion, repetitive motion, and bodily reaction. They believed that there were direct and indirect costs associated with workplace injuries and for every dollar spent improving workplace safety, more than four dollars would be returned. They perceived the top benefits of an effective safety program to be predominately financial in nature - increased productivity and reduced costs - and the safety modification participants mentioned most often was to have more/better safety-focused training. However, more participants from large- than medium-size companies reported that "falling on the same level" was the major cause of workers' compensation loss, which is in line with industry loss data. Participants from large companies were more likely to see their safety programs as better than those of other companies in their industries, and those of medium-size companies were more likely to mention that there were no improvements needed for their companies. Copyright © 2009 Elsevier Ltd. All rights reserved.

  8. Estimation of body-size traits by photogrammetry in large mammals to inform conservation.

    Science.gov (United States)

    Berger, Joel

    2012-10-01

    Photography, including remote imagery and camera traps, has contributed substantially to conservation. However, the potential to use photography to understand demography and inform policy is limited. To have practical value, remote assessments must be reasonably accurate and widely deployable. Prior efforts to develop noninvasive methods of estimating trait size have been motivated by a desire to answer evolutionary questions, measure physiological growth, or, in the case of illegal trade, assess economics of horn sizes; but rarely have such methods been directed at conservation. Here I demonstrate a simple, noninvasive photographic technique and address how knowledge of values of individual-specific metrics bears on conservation policy. I used 10 years of data on juvenile moose (Alces alces) to examine whether body size and probability of survival are positively correlated in cold climates. I investigated whether the presence of mothers improved juvenile survival. The posited latter relation is relevant to policy because harvest of adult females has been permitted in some Canadian and American jurisdictions under the assumption that probability of survival of young is independent of maternal presence. The accuracy of estimates of head sizes made from photographs exceeded 98%. The estimates revealed that overwinter juvenile survival had no relation to the juvenile's estimated mass (p < 0.64) and was more strongly associated with maternal presence (p < 0.02) than winter snow depth (p < 0.18). These findings highlight the effects on survival of a social dynamic (the mother-young association) rather than body size and suggest a change in harvest policy will increase survival. Furthermore, photographic imaging of growth of individual juvenile muskoxen (Ovibos moschatus) over 3 Arctic winters revealed annual variability in size, which supports the idea that noninvasive monitoring may allow one to detect how some environmental conditions ultimately affect body growth.

  9. 40 CFR 141.81 - Applicability of corrosion control treatment steps to small, medium-size and large water systems.

    Science.gov (United States)

    2010-07-01

    ... treatment steps to small, medium-size and large water systems. 141.81 Section 141.81 Protection of... WATER REGULATIONS Control of Lead and Copper § 141.81 Applicability of corrosion control treatment steps...). (ii) A report explaining the test methods used by the water system to evaluate the corrosion control...

  10. Does company size matter? Validation of an integrative model of safety behavior across small and large construction companies.

    Science.gov (United States)

    Guo, Brian H W; Yiu, Tak Wing; González, Vicente A

    2018-02-01

    Previous safety climate studies primarily focused on either large construction companies or the construction industry as a whole, while little is known about whether company size has significant effects on workers' understanding of safety climate measures and relationships between safety climate factors and safety behavior. Thus, this study aims to: (a) test the measurement equivalence (ME) of a safety climate measure across workers from small and large companies; (b) investigate if company size alters the causal structure of the integrative model developed by Guo, Yiu, and González (2016). Data were collected from 253 construction workers in New Zealand using a safety climate measure. This study used multi-group confirmatory factor analyses (MCFA) to test the measurement equivalence of the safety climate measure and structure invariance of the integrative model. Results indicate that workers from small and large companies understood the safety climate measure in a similar manner. In addition, it was suggested that company size does not change the causal structure and mediational processes of the integrative model. Both measurement equivalence of the safety climate measure and structural invariance of the integrative model were supported by this study. Practical applications: Findings of this study provided strong support for a meaningful use of the safety climate measure across construction companies in different sizes. Safety behavior promotion strategies designed based on the integrative model may be well suited for both large and small companies. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.

  11. PERSPECTIVE TECHNOLOGIES OF THERMAL HARDENING OF LARGE-SIZE ARTICLES OF TWO-PHASE TITANIUM ALLOYS

    Directory of Open Access Journals (Sweden)

    V. N. Fedulov

    2005-01-01

    Full Text Available The article is dedicated to the development and industrial assimilation of the fundamentally new methods of thermal strengthening of large articles out of hardenable titanic alloys.

  12. Job Stress in the United Kingdom: Are Small and Medium-Sized Enterprises and Large Enterprises Different?

    Science.gov (United States)

    Lai, Yanqing; Saridakis, George; Blackburn, Robert

    2015-08-01

    This paper examines the relationships between firm size and employees' experience of work stress. We used a matched employer-employee dataset (Workplace Employment Relations Survey 2011) that comprises of 7182 employees from 1210 private organizations in the United Kingdom. Initially, we find that employees in small and medium-sized enterprises experience lower level of overall job stress than those in large enterprises, although the effect disappears when we control for individual and organizational characteristics in the model. We also find that quantitative work overload, job insecurity and poor promotion opportunities, good work relationships and poor communication are strongly associated with job stress in the small and medium-sized enterprises, whereas qualitative work overload, poor job autonomy and employee engagements are more related with larger enterprises. Hence, our estimates show that the association and magnitude of estimated effects differ significantly by enterprise size. Copyright © 2013 John Wiley & Sons, Ltd.

  13. Flexible Multi-Bit Feedback Design for HARQ Operation of Large-Size Data Packets in 5G

    DEFF Research Database (Denmark)

    Khosravirad, Saeed; Mudolo, Luke; Pedersen, Klaus I.

    2017-01-01

    large-size data packet thanks to which the transmitter node can reduce the retransmission size to only include the initially failed segments of the packet. We study the effect of feedback size on retransmission efficiency through extensive link-level simulations over realistic channel models. Numerical......A reliable feedback channel is vital to report decoding acknowledgments in retransmission mechanisms such as the hybrid automatic repeat request (HARQ). While the feedback bits are known to be costly for the wireless link, a feedback message more informative than the conventional single......-bit feedback can increase resource utilization efficiency. Considering the practical limitations for increasing feedback message size, this paper proposes a framework for the design of flexible-content multi-bit feedback. The proposed design is capable of efficiently indicating the faulty segments of a failed...

  14. The maximum sizes of large scale structures in alternative theories of gravity

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Sourav [IUCAA, Pune University Campus, Post Bag 4, Ganeshkhind, Pune, 411 007 India (India); Dialektopoulos, Konstantinos F. [Dipartimento di Fisica, Università di Napoli ' Federico II' , Complesso Universitario di Monte S. Angelo, Edificio G, Via Cinthia, Napoli, I-80126 Italy (Italy); Romano, Antonio Enea [Instituto de Física, Universidad de Antioquia, Calle 70 No. 52–21, Medellín (Colombia); Skordis, Constantinos [Department of Physics, University of Cyprus, 1 Panepistimiou Street, Nicosia, 2109 Cyprus (Cyprus); Tomaras, Theodore N., E-mail: sbhatta@iitrpr.ac.in, E-mail: kdialekt@gmail.com, E-mail: aer@phys.ntu.edu.tw, E-mail: skordis@ucy.ac.cy, E-mail: tomaras@physics.uoc.gr [Institute of Theoretical and Computational Physics and Department of Physics, University of Crete, 70013 Heraklion (Greece)

    2017-07-01

    The maximum size of a cosmic structure is given by the maximum turnaround radius—the scale where the attraction due to its mass is balanced by the repulsion due to dark energy. We derive generic formulae for the estimation of the maximum turnaround radius in any theory of gravity obeying the Einstein equivalence principle, in two situations: on a spherically symmetric spacetime and on a perturbed Friedman-Robertson-Walker spacetime. We show that the two formulae agree. As an application of our formula, we calculate the maximum turnaround radius in the case of the Brans-Dicke theory of gravity. We find that for this theory, such maximum sizes always lie above the ΛCDM value, by a factor 1 + 1/3ω, where ω>> 1 is the Brans-Dicke parameter, implying consistency of the theory with current data.

  15. Occupational lifting during pregnancy and child's birth size in a large cohort study

    DEFF Research Database (Denmark)

    Juhl, Mette; Larsen, Pernille Stemann; Andersen, Per Kragh

    2014-01-01

    OBJECTIVES: It has been suggested that the handling of heavy loads during pregnancy is associated with impaired fetal growth. We examined the association between quantity and frequency of maternal occupational lifting and the child's size at birth, measured by weight, length, ponderal index, small......-for-gestational-age (SGA), abdominal circumference, head circumference, and placental weight. METHODS: We analyzed birth size from the Danish Medical Birth Registry of 66 693 live-born children in the Danish National Birth Cohort according to the mother's self-reported information on occupational lifting from telephone...... women with occupational lifting versus women with no lifting, but the differences were very small, and there was a statistically significant trend only for placental weight showing lighter weight with increasing number of kilos lifted per day. In jobs likely to include person-lifting, we found increased...

  16. A test of the mean density approximation for Lennard-Jones mixtures with large size ratios

    International Nuclear Information System (INIS)

    Ely, J.F.

    1986-01-01

    The mean density approximation for mixture radial distribution functions plays a central role in modern corresponding-states theories. This approximation is reasonably accurate for systems that do not differ widely in size and energy ratios and which are nearly equimolar. As the size ratio increases, however, or if one approaches an infinite dilution of one of the components, the approximation becomes progressively worse, especially for the small molecule pair. In an attempt to better understand and improve this approximation, isothermal molecular dynamics simulations have been performed on a series of Lennard-Jones mixtures. Thermodynamic properties, including the mixture radial distribution functions, have been obtained at seven compositions ranging from 5 to 95 mol%. In all cases the size ratio was fixed at two and three energy ratios were investigated, 22 / 11 =0.5, 1.0, and 1.5. The results of the simulations are compared with the mean density approximation and a modification to integrals evaluated with the mean density approximation is proposed

  17. Sediment size of surface floodplain sediments along a large lowland river

    Science.gov (United States)

    Swanson, K. M.; Day, G.; Dietrich, W. E.

    2007-12-01

    Data on size distribution of surface sediment across a floodplain should place important constraints of modeling of floodplain deposition. Diffusive or advective models would predict that, generally, grain size should decrease away from channel banks. Variations in grain size downstream along floodplains may depend on downstream fining of river bed material, exchange rate with river banks and net deposition onto the floodplain. Here we report detailed grain size analyses taken from 17 floodplain transects along 450 km (along channel distance) reach of the middle Fly River, Papua New Guinea. Field studies have documented a systematic change in floodplain characteristics downstream from forested, more topographically elevated and topography bounded by an actively shifting mainstem channel to a downstream swamp grass, low elevation topography along which the river meanders are currently stagnant. Frequency and duration of flooding increase downstream. Flooding occurs both by overbank flows and by injections of floodwaters up tributary and tie channels connected to the mainstem. Previous studies show that about 40% of the total discharge of water passes across the floodplain, and, correspondingly, about 40% of the total load is deposited on the plain - decreasing exponentially from channel bank. We find that floodplain sediment is most sandy at the channel bank. Grain size rapidly declines away from the bank, but surprisingly two trends were also observed. A relatively short distance from the bank the surface material is finest, but with further distance from the bank (out to greater than 1 km from the 250 m wide channel) clay content decreases and silt content increases. The changes are small but repeated at most of the transects. The second trend is that bank material fines downstream, corresponding to a downstream finding bed material, but once away from the bank, there is a weak tendency for a given distance away from the bank the floodplain surface deposits to

  18. Prevalence of intestinal pathogens in Danish finishing pig herds

    DEFF Research Database (Denmark)

    Stege, H.; Jensen, Tim Kåre; Møller, Kristian

    2000-01-01

    Our aim was to determine the prevalence of the intestinal bacteria: Lawsonia intracellularis, Brachyspira hyodysenteriae, Serpulina intermedia, Brachyspira innocens, Brachyspira pilosicoli, pathogenic Escherichia coli (serogroups 0138, 0139, 0141 and 0149) and Salmonella enterica in Danish...... were collected and examined by polymerase chain reaction (PCR) or culture. L. intracellularis was found in 74 herds (93.7%), B. hyodysenteriae in two herds (2.5%), S. intermedia in 10 herds (12.7%), B. innocens in 27 herds (34.2%), B. pilosicoli in 15 herds (19.0%), pathogenic E. call in 19 herds (24...

  19. Mitigating Herding in Hierarchical Crowdsourcing Networks.

    Science.gov (United States)

    Yu, Han; Miao, Chunyan; Leung, Cyril; Chen, Yiqiang; Fauvel, Simon; Lesser, Victor R; Yang, Qiang

    2016-12-05

    Hierarchical crowdsourcing networks (HCNs) provide a useful mechanism for social mobilization. However, spontaneous evolution of the complex resource allocation dynamics can lead to undesirable herding behaviours in which a small group of reputable workers are overloaded while leaving other workers idle. Existing herding control mechanisms designed for typical crowdsourcing systems are not effective in HCNs. In order to bridge this gap, we investigate the herding dynamics in HCNs and propose a Lyapunov optimization based decision support approach - the Reputation-aware Task Sub-delegation approach with dynamic worker effort Pricing (RTS-P) - with objective functions aiming to achieve superlinear time-averaged collective productivity in an HCN. By considering the workers' current reputation, workload, eagerness to work, and trust relationships, RTS-P provides a systematic approach to mitigate herding by helping workers make joint decisions on task sub-delegation, task acceptance, and effort pricing in a distributed manner. It is an individual-level decision support approach which results in the emergence of productive and robust collective patterns in HCNs. High resolution simulations demonstrate that RTS-P mitigates herding more effectively than state-of-the-art approaches.

  20. Fatigue-crack propagation in gamma-based titanium aluminide alloys at large and small crack sizes

    International Nuclear Information System (INIS)

    Kruzic, J.J.; Campbell, J.P.; Ritchie, R.O.

    1999-01-01

    Most evaluations of the fracture and fatigue-crack propagation properties of γ+α 2 titanium aluminide alloys to date have been performed using standard large-crack samples, e.g., compact-tension specimens containing crack sizes which are on the order of tens of millimeters, i.e., large compared to microstructural dimensions. However, these alloys have been targeted for applications, such as blades in gas-turbine engines, where relevant crack sizes are much smaller ( 5 mm) and (c ≅ 25--300 microm) cracks in a γ-TiAl based alloy, of composition Ti-47Al-2Nb-2Cr-0.2B (at.%), specifically for duplex (average grain size approximately17 microm) and refined lamellar (average colony size ≅150 microm) microstructures. It is found that, whereas the lamellar microstructure displays far superior fracture toughness and fatigue-crack growth resistance in the presence of large cracks, in small-crack testing the duplex microstructure exhibits a better combination of properties. The reasons for such contrasting behavior are examined in terms of the intrinsic and extrinsic (i.e., crack bridging) contributions to cyclic crack advance

  1. Maximizing Use of Extension Beef Cattle Benchmarks Data Derived from Cow Herd Appraisal Performance Software

    Science.gov (United States)

    Ramsay, Jennifer M.; Hanna, Lauren L. Hulsman; Ringwall, Kris A.

    2016-01-01

    One goal of Extension is to provide practical information that makes a difference to producers. Cow Herd Appraisal Performance Software (CHAPS) has provided beef producers with production benchmarks for 30 years, creating a large historical data set. Many such large data sets contain useful information but are underutilized. Our goal was to create…

  2. Highly crystallized nanometer-sized zeolite a with large Cs adsorption capability for the decontamination of water.

    Science.gov (United States)

    Torad, Nagy L; Naito, Masanobu; Tatami, Junichi; Endo, Akira; Leo, Sin-Yen; Ishihara, Shinsuke; Wu, Kevin C-W; Wakihara, Toru; Yamauchi, Yusuke

    2014-03-01

    Nanometer-sized zeolite A with a large cesium (Cs) uptake capability is prepared through a simple post-milling recrystallization method. This method is suitable for producing nanometer-sized zeolite in large scale, as additional organic compounds are not needed to control zeolite nucleation and crystal growth. Herein, we perform a quartz crystal microbalance (QCM) study to evaluate the uptake ability of Cs ions by zeolite, to the best of our knowledge, for the first time. In comparison to micrometer-sized zeolite A, nanometer-sized zeolite A can rapidly accommodate a larger amount of Cs ions into the zeolite crystal structure, owing to its high external surface area. Nanometer-sized zeolite is a promising candidate for the removal of radioactive Cs ions from polluted water. Our QCM study on Cs adsorption uptake behavior provides the information of adsorption kinetics (e.g., adsorption amounts and rates). This technique is applicable to other zeolites, which will be highly valuable for further consideration of radioactive Cs removal in the future. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Herd composition and slaughtering strategy in reindeer husbandry – revisited

    Directory of Open Access Journals (Sweden)

    Øystein Holand

    2007-04-01

    traditional knowledge, started in Riast/Hylling reindeer herding district in southern Norway in the early 1970s and was completed around 1985. The work was followed up in Ruvhten Sitje (earlier called Tännäs Sameby, the neighbouring herding community of Riast/Hylling on the Swedish side of the border. In its stringent form the modern herd should comprise the highest proportion possible of reproductive females. The stocking rate should be adjusted to allow females to reproduce early; preferably at an age of 1.5 year, and they should be able to raise calves successfully every year. The male segment should be large enough to serve the females successfully during rut. Using 1.5 years old males as breeding bulls means that they can be slaughtered after rut. The culling should primarily aim at calves and removal of females reaching reproductive senescence, normally at around 12 years of age. Only the best female calves are selected as replacement of the senescence females slaughtered and the best male calves are selected as breeding bulls for the next year's rut. Calculations suggest that this new herd composition and slaughtering strategy could increase the meat production per area unit by around 50% compared to a traditional herd composition and off take scheme. However, such a strategy necessitates a strict control of environmental factors, including forage resources, as well as predators and human disturbance. Breeding programme based on selection on autumn calf weight has been proven successful. This work has been carried out in Ruvhten Sitje. The challenge is to establish appropriate breeding objectives in an ever changing environment. Selection for only calf weight may lead to improvement of capacity of growth only, which necessitates improvement of the environment in order to realize the genetic potential. Emphasize on maternal ability may lead to increase efficiency. To secure the genetic improvement in an open nucleus breeding scheme, with partly different breeding

  4. Neonatal L-glutamine modulates anxiety-like behavior, cortical spreading depression, and microglial immunoreactivity: analysis in developing rats suckled on normal size- and large size litters.

    Science.gov (United States)

    de Lima, Denise Sandrelly Cavalcanti; Francisco, Elian da Silva; Lima, Cássia Borges; Guedes, Rubem Carlos Araújo

    2017-02-01

    In mammals, L-glutamine (Gln) can alter the glutamate-Gln cycle and consequently brain excitability. Here, we investigated in developing rats the effect of treatment with different doses of Gln on anxiety-like behavior, cortical spreading depression (CSD), and microglial activation expressed as Iba1-immunoreactivity. Wistar rats were suckled in litters with 9 and 15 pups (groups L 9 and L 15 ; respectively, normal size- and large size litters). From postnatal days (P) 7-27, the animals received Gln per gavage (250, 500 or 750 mg/kg/day), or vehicle (water), or no treatment (naive). At P28 and P30, we tested the animals, respectively, in the elevated plus maze and open field. At P30-35, we measured CSD parameters (velocity of propagation, amplitude, and duration). Fixative-perfused brains were processed for microglial immunolabeling with anti-IBA-1 antibodies to analyze cortical microglia. Rats treated with Gln presented an anxiolytic behavior and accelerated CSD propagation when compared to the water- and naive control groups. Furthermore, CSD velocity was higher (p litter sizes, and for microglial activation in the L 15 groups. Besides confirming previous electrophysiological findings (CSD acceleration after Gln), our data demonstrate for the first time a behavioral and microglial activation that is associated with early Gln treatment in developing animals, and that is possibly operated via changes in brain excitability.

  5. Neospora caninum in beef herds in New South Wales, Australia. 2: analysis of risk factors.

    Science.gov (United States)

    Moloney, B J; Heuer, C; Kirkland, P D

    2017-04-01

    To determine the influence of farm-level and animal-level factors on the seroprevalence of antibodies to Neospora caninum and associations between seropositivity and reproductive outcomes. A questionnaire for a cross-sectional survey was posted to the 63 properties with a herd size ≥50 beef breeding cows that had participated in a previous seroprevalence study. Correspondence analysis, which does not appear to have been used previously in any Australian studies of livestock diseases, was used in conjunction with logistic regression to analyse the data. Geographic factors that increased the risk of seropositivity included higher rainfall North Coast location. Herd management factors that increased the risk of seropositivity included the use of Bos indicus genetics, cross-breeding and running several breeds in the one herd. Using fox control measures was found to be protective against infection with N. caninum. The risk of abortion was 12-fold greater in individual animals that were seropositive for N. caninum. Within a herd, the calving rate was 10.4% lower in herds with one or more N. caninum-positive animals (P = 0.03), but the difference in abortion rate was not significant between seropositive and seronegative herds (0.3% higher, P > 0.3). This study confirmed previous observations of increased risks for N. caninum seropositivity with being located in the coastal subtropics, some styles of herd management and canid exposure. In addition, it suggested that cross-breeding and proximity to an urban area may increase the risk, and that having pet dogs may reduce the risk of seropositivity. © 2017 State of New South Wales.

  6. Bacteriological etiology and treatment of mastitis in Finnish dairy herds.

    Science.gov (United States)

    Vakkamäki, Johanna; Taponen, Suvi; Heikkilä, Anna-Maija; Pyörälä, Satu

    2017-05-25

    The Finnish dairy herd recording system maintains production and health records of cows and herds. Veterinarians and farmers register veterinary treatments in the system. Milk samples for microbiological analysis are routinely taken from mastitic cows. The laboratory of the largest dairy company in Finland, Valio Ltd., analyzes most samples using real-time PCR. This study addressed pathogen-specific microbiological data and treatment and culling records, in combination with cow and herd characteristics, from the Finnish dairy herd recording system during 2010-2012. The data derived from 240,067 quarter milk samples from 93,529 dairy cows with mastitis; 238,235 cows from the same herds served as the control group. No target pathogen DNA was detected in 12% of the samples. In 49% of the positive samples, only one target species and in 19%, two species with one dominant species were present. The most common species in the samples with a single species only were coagulase-negative staphylococci (CNS) (43%), followed by Staphylococcus aureus (21%), Streptococcus uberis (9%), Streptococcus dysgalactiae (8%), Corynebacterium bovis (7%), and Escherichia coli (5%). On average, 36% of the study cows and 6% of the control cows had recorded mastitis treatments during lactation. The corresponding proportions were 16 and 6% at drying-off. For more than 75% of the treatments during lactation, diagnosis was acute clinical mastitis. In the milk samples from cows with a recorded mastitis treatment during lactation, CNS and S. aureus were most common, followed by streptococci. Altogether, 48% of the cows were culled during the study. Mastitis was reported as the most common reason to cull; 49% of study cows and 18% of control cows were culled because of mastitis. Culling was most likely if S. aureus was detected in the milk sample submitted during the culling year. The PCR test has proven to be an applicable method also for large-scale use in bacterial diagnostics. In the present

  7. Participation and Collaborative Learning in Large Class Sizes: Wiki, Can You Help Me?

    Science.gov (United States)

    de Arriba, Raúl

    2017-01-01

    Collaborative learning has a long tradition within higher education. However, its application in classes with a large number of students is complicated, since it is a teaching method that requires a high level of participation from the students and careful monitoring of the process by the educator. This article presents an experience in…

  8. Organizing Corporate Social Responsibility in Small and Large Firms: Size Matters

    NARCIS (Netherlands)

    Baumann-Pauly, D.; Wickert, C.M.J.; Spence, L.; Scherer, A.G.

    2013-01-01

    Based on the findings of a qualitative empirical study of corporate social responsibility (CSR) in Swiss MNCs and SMEs, we suggest that smaller firms are not necessarily less advanced in organizing CSR than large firms. Results according to theoretically derived assessment frameworks illustrate the

  9. Determining an Estimate of an Equivalence Relation for Moderate and Large Sized Sets

    Directory of Open Access Journals (Sweden)

    Leszek Klukowski

    2017-01-01

    Full Text Available This paper presents two approaches to determining estimates of an equivalence relation on the basis of pairwise comparisons with random errors. Obtaining such an estimate requires the solution of a discrete programming problem which minimizes the sum of the differences between the form of the relation and the comparisons. The problem is NP hard and can be solved with the use of exact algorithms for sets of moderate size, i.e. about 50 elements. In the case of larger sets, i.e. at least 200 comparisons for each element, it is necessary to apply heuristic algorithms. The paper presents results (a statistical preprocessing, which enable us to determine the optimal or a near-optimal solution with acceptable computational cost. They include: the development of a statistical procedure producing comparisons with low probabilities of errors and a heuristic algorithm based on such comparisons. The proposed approach guarantees the applicability of such estimators for any size of set. (original abstract

  10. Mapping trends of large and medium size carnivores of conservation interest in Romania

    Directory of Open Access Journals (Sweden)

    Constantin Cazacu

    2014-07-01

    Full Text Available We analysed yearly estimates of population size data during 2001-2012 for five carnivores species of conservation interest (Ursus arctos, Canis lupus, Lynx lynx, Felis silvestris and Canis aureus. Population size estimations were done by the game management authorities and integrated by the competent authorities on the Ministry of Environment and Climate Change. Trends in data were detected using non-parametric Mann-Kendall test. This test was chosen considering the short length of data series and its usefulness for non-normal distributed data. The trend was tested at three spatial scales: game management units (n=1565, biogeographical region (n=5 and national. Trends depicted for each game management unit were plotted using ArcGIS, resulting species trend distribution maps. For the studied period increasing population trends were observed for Ursus arctos, Canis lupus, Canis aureus and Lynx lynx, while for Felis silvestris there was no trend recorded. Such an analysis in especially useful for conservation proposes, game management and reporting obligations under article 17 of the EC Habitat Directive, using population trend as a proxy for population dynamics. We conclude that the status of the five carnivore species is favourable during the study period.

  11. THE PHYSICS OF PROTOPLANETESIMAL DUST AGGLOMERATES. VI. EROSION OF LARGE AGGREGATES AS A SOURCE OF MICROMETER-SIZED PARTICLES

    International Nuclear Information System (INIS)

    Schraepler, Rainer; Blum, Juergen

    2011-01-01

    Observed protoplanetary disks consist of a large amount of micrometer-sized particles. Dullemond and Dominik pointed out for the first time the difficulty in explaining the strong mid-infrared excess of classical T Tauri stars without any dust-retention mechanisms. Because high relative velocities in between micrometer-sized and macroscopic particles exist in protoplanetary disks, we present experimental results on the erosion of macroscopic agglomerates consisting of micrometer-sized spherical particles via the impact of micrometer-sized particles. We find that after an initial phase, in which an impacting particle erodes up to 10 particles of an agglomerate, the impacting particles compress the agglomerate's surface, which partly passivates the agglomerates against erosion. Due to this effect, the erosion halts for impact velocities up to ∼30 m s -1 within our error bars. For higher velocities, the erosion is reduced by an order of magnitude. This outcome is explained and confirmed by a numerical model. In a next step, we build an analytical disk model and implement the experimentally found erosive effect. The model shows that erosion is a strong source of micrometer-sized particles in a protoplanetary disk. Finally, we use the stationary solution of this model to explain the amount of micrometer-sized particles in the observational infrared data of Furlan et al.

  12. Development of large size Micromegas detectors for the upgrade of the ATLAS experiments

    CERN Document Server

    Bianco, Michele

    2014-01-01

    The luminosity upgrade of the Large Hadron Collider at CERN f oresees a luminosity increase by a factor 3 compared to the LHC luminosity design value. To c ope with the corresponding rate increase, the Muon System of the ATLAS experiment at CER N needs to be upgraded. In the first station of the high rapidity region, micromegas det ectors have been chosen as the main tracking chambers but will, at the same time, also contribut e to the trigger. We describe the R&D; efforts that led to the construction of the first (1 × 2.4 m 2 ) large micromegas detectors at CERN and outline the next steps towards the construction of the 12 00 m 2 of micromegas detectors for the ATLAS upgrade. The technical solutions, adopted in the c onstruction of the chamber as well as results on the detector performance with cosmic rays are s hown.

  13. Abortion studies in Iranian dairy herds

    DEFF Research Database (Denmark)

    Keshavarzi, Hamideh; Sadeghi-Sefidmazgi, Ali; Kristensen, Anders Ringgaard

    2017-01-01

    Abortions, especially those occurring during late pregnancy, lead to considerable economic losses. To estimate the financial losses related to pregnancy loss, at first the influencing factors on abortion need to be identified. Thus, the objective of this study was to determine and quantify the risk...... factors and their interactions for abortion in Iranian dairy herds. Based on data from 6 commercial herds, logistic regression was used to identify the risk factors for abortion. The basic time unit used in the study was a 3-week period corresponding to an estrus cycle. Thus, stage of lactation...... factors were herd effect, pregnancy stage, previous abortion, calving month, cumulative fat corrected milk (FCM) yield level, mastitis in current 3-weeks in milk, accumulated number of mastitis and all 2-way interactions. Pregnancy tests were performed between 35 and 50 days after insemination. Abortion...

  14. Post-mastectomy radiation in large node-negative breast tumors: Does size really matter?

    International Nuclear Information System (INIS)

    Floyd, Scott R.; Taghian, Alphonse G.

    2009-01-01

    Treatment decisions regarding local control can be particularly challenging for T3N0 breast tumors because of difficulty in estimating rates of local failure after mastectomy. Reports in the literature detailing the rates of local failure vary widely, likely owing to the uncommon incidence of this clinical situation. The literature regarding this clinical scenario is reviewed, including recent reports that specifically address the issue of local failure rates after mastectomy in the absence of radiation for large node-negative breast tumors.

  15. Large-size high-performance transparent amorphous silicon sensors for laser beam position detection

    International Nuclear Information System (INIS)

    Calderon, A.; Martinez-Rivero, C.; Matorras, F.; Rodrigo, T.; Sobron, M.; Vila, I.; Virto, A.L.; Alberdi, J.; Arce, P.; Barcala, J.M.; Calvo, E.; Ferrando, A.; Josa, M.I.; Luque, J.M.; Molinero, A.; Navarrete, J.; Oller, J.C.; Yuste, C.; Koehler, C.; Lutz, B.; Schubert, M.B.; Werner, J.H.

    2006-01-01

    We present the measured performance of a new generation of semitransparent amorphous silicon position detectors. They have a large sensitive area (30x30mm 2 ) and show good properties such as a high response (about 20mA/W), an intrinsic position resolution better than 3μm, a spatial-point reconstruction precision better than 10μm, deflection angles smaller than 10μrad and a transmission power in the visible and NIR higher than 70%

  16. Diversity of medium and large sized mammals in a Cerrado fragment of central Brazil

    Directory of Open Access Journals (Sweden)

    F.S. Campos

    2013-11-01

    Full Text Available Studies related to community ecology of medium and large mammals represent a priority in developing strategies for conservation of their habitats. Due to the significant ecological importance of these species, a concern in relation to anthropogenic pressures arises since their populations are vulnerable to hunting and fragmentation. In this study, we aimed to analyze the diversity of medium and large mammals in a representative area of the Cerrado biome, located in the National Forest of Silvânia, central Brazil, providing insights for future studies on the biodiversity and conservation of Cerrado mammals. Sampling was carried out by linear transects, search for traces, footprint traps and camera traps. We recorded 23 species, among which three are listed in threat categories (e.g., Myrmecophaga tridactyla, Chrysocyon brachyurus and Leopardus tigrinus. We registered 160 records in the study area, where the most frequently recorded species were Didelphis albiventris (30 records and Cerdocyon thous (28 records. Our results indicated that a small protected area of Cerrado can include a large and important percentage of the diversity of mammals in this biome, providing information about richness, abundance, spatial distribution and insights for future studies on the biodiversity and conservation of these biological communities.

  17. Azimuthal coil size and field quality in the main CERN Large Hadron Collider dipoles

    Directory of Open Access Journals (Sweden)

    P. Ferracin

    2002-06-01

    Full Text Available Field quality in superconducting magnets strongly depends on the geometry of the coil. Fiberglass spacers (shims placed between the coil and the collars have been used to optimize magnetic and mechanical performances of superconducting magnets in large accelerators. A change in the shim thickness affects both the geometry of the coil and its state of compression (prestress under operational conditions. In this paper we develop a coupled magnetomechanical model of the main Large Hadron Collider dipole. This model allows us to evaluate the prestress dependence on the shim thickness and the map of deformations of the coil and the collars. Results of the model are compared to experimental measurements carried out in a dedicated experiment, where a magnet model has been reassembled 5 times with different shims. A good agreement is found between simulations and experimental data both on the mechanical behavior and on the field quality. We show that this approach allows us to improve this agreement with respect to models previously used in the literature. We finally evaluate the range of tunability that will be provided by shims during the production of the Large Hadron Collider main dipoles.

  18. Associations of breed and feeding management with milk production curves at herd level using a random regression test-day model

    NARCIS (Netherlands)

    Caccamo, M.; Veerkamp, R.F.; Ferguson, J.D.; Petriglieri, R.; Terra, La F.; Licitra, G.

    2010-01-01

    Earlier studies identified large between-herd variation in estimated lactation curve parameters from test-day milk yield and milk composition records collected in Ragusa province, Italy. The objective of this study was to identify sources of variation able to explain these between-herd differences

  19. Early outcome in renal transplantation from large donors to small and size-matched recipients - a porcine experimental model

    DEFF Research Database (Denmark)

    Ravlo, Kristian; Chhoden, Tashi; Søndergaard, Peter

    2012-01-01

    in small recipients within 60 min after reperfusion. Interestingly, this was associated with a significant reduction in medullary RPP, while there was no significant change in the size-matched recipients. No difference was observed in urinary NGAL excretion between the groups. A significant higher level......Kidney transplantation from a large donor to a small recipient, as in pediatric transplantation, is associated with an increased risk of thrombosis and DGF. We established a porcine model for renal transplantation from an adult donor to a small or size-matched recipient with a high risk of DGF...... and studied GFR, RPP using MRI, and markers of kidney injury within 10 h after transplantation. After induction of BD, kidneys were removed from ∼63-kg donors and kept in cold storage for ∼22 h until transplanted into small (∼15 kg, n = 8) or size-matched (n = 8) recipients. A reduction in GFR was observed...

  20. Salt-assisted direct exfoliation of graphite into high-quality, large-size, few-layer graphene sheets.

    Science.gov (United States)

    Niu, Liyong; Li, Mingjian; Tao, Xiaoming; Xie, Zhuang; Zhou, Xuechang; Raju, Arun P A; Young, Robert J; Zheng, Zijian

    2013-08-21

    We report a facile and low-cost method to directly exfoliate graphite powders into large-size, high-quality, and solution-dispersible few-layer graphene sheets. In this method, aqueous mixtures of graphite and inorganic salts such as NaCl and CuCl2 are stirred, and subsequently dried by evaporation. Finally, the mixture powders are dispersed into an orthogonal organic solvent solution of the salt by low-power and short-time ultrasonication, which exfoliates graphite into few-layer graphene sheets. We find that the as-made graphene sheets contain little oxygen, and 86% of them are 1-5 layers with lateral sizes as large as 210 μm(2). Importantly, the as-made graphene can be readily dispersed into aqueous solution in the presence of surfactant and thus is compatible with various solution-processing techniques towards graphene-based thin film devices.

  1. Optimal integrated sizing and planning of hubs with midsize/large CHP units considering reliability of supply

    International Nuclear Information System (INIS)

    Moradi, Saeed; Ghaffarpour, Reza; Ranjbar, Ali Mohammad; Mozaffari, Babak

    2017-01-01

    Highlights: • New hub planning formulation is proposed to exploit assets of midsize/large CHPs. • Linearization approaches are proposed for two-variable nonlinear CHP fuel function. • Efficient operation of addressed CHPs & hub devices at contingencies are considered. • Reliability-embedded integrated planning & sizing is formulated as one single MILP. • Noticeable results for costs & reliability-embedded planning due to mid/large CHPs. - Abstract: Use of multi-carrier energy systems and the energy hub concept has recently been a widespread trend worldwide. However, most of the related researches specialize in CHP systems with constant electricity/heat ratios and linear operating characteristics. In this paper, integrated energy hub planning and sizing is developed for the energy systems with mid-scale and large-scale CHP units, by taking their wide operating range into consideration. The proposed formulation is aimed at taking the best use of the beneficial degrees of freedom associated with these units for decreasing total costs and increasing reliability. High-accuracy piecewise linearization techniques with approximation errors of about 1% are introduced for the nonlinear two-dimensional CHP input-output function, making it possible to successfully integrate the CHP sizing. Efficient operation of CHP and the hub at contingencies is extracted via a new formulation, which is developed to be incorporated to the planning and sizing problem. Optimal operation, planning, sizing and contingency operation of hub components are integrated and formulated as a single comprehensive MILP problem. Results on a case study with midsize CHPs reveal a 33% reduction in total costs, and it is demonstrated that the proposed formulation ceases the need for additional components/capacities for increasing reliability of supply.

  2. Dairy Herd Mastitis Program in Argentina: Farm Clusters and Effects on Bulk Milk Somatic Cell Counts

    Directory of Open Access Journals (Sweden)

    C Vissio1*, SA Dieser2, CG Raspanti2, JA Giraudo1, CI Bogni2, LM Odierno2 and AJ Larriestra1

    2013-01-01

    Full Text Available This research has been conducted to characterize dairy farm clusters according to mastitis control program practiced among small and medium dairy producer from Argentina, and also to evaluate the effect of such farm cluster patterns on bulk milk somatic cell count (BMSCC. Two samples of 51 (cross-sectional and 38 (longitudinal herds were selected to identify farm clusters and study the influence of management on monthly BMSCC, respectively. The cross-sectional sample involved the milking routine and facilities assessment of each herd visited. Hierarchical cluster analysis was used to find the most discriminating farm attributes in the cross sectional sample. Afterward, the herd cluster typologies were identified in the longitudinal sample. Herd monthly BMSCC average was evaluated during 12 months fitting a linear mixed model. Two clusters were identified, the farms in the Cluster I applied a comprehensive mastitis program in opposite to Cluster II. Post-dipping, dry cow therapy and milking machine test were routinely applied in Cluster I. In the longitudinal study, 14 out of 38 dairy herds were labeled as Cluster I and the rest were assigned to Cluster II. Significant difference in BMSCC was found between cluster I and II (60,000 cells/mL. The present study showed the relevance and potential impact of promoting mastitis control practices among small and medium sized dairy producers in Argentina.

  3. Visual monitoring of reproduction in dairy herds

    DEFF Research Database (Denmark)

    Thysen, Iver; Enevoldsen, Carsten

    1994-01-01

    Two complementary approaches to produce visual information from reproduction records are described and exemplified. The Event Display shows all reproductive events, over a year, for all cows in a herd, by symbols placed in an array with columns representing calendar weeks and rows representing...... individual cows. The Reproduction Monitor consists of graphs of insemination and pregnancy rates evaluated weekly with a Bayesian technique. These visual monitoring tools are well suited to explore temporal variation in reproductive performance, they provide a quick overview of herd performance...

  4. Large Size High Performance Transparent Amorphous Silicon Sensors for Laser Beam Position Detection and Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Calderon, A.; Martinez Rivero, C.; Matorras, F.; Rodrigo, T.; Sobron, M.; Vila, I.; Virto; Alberdi, J.; Arce, P.; Barcala, J. M.; Calvo, E.; Ferrando, A.; Josa, M. I.; Luque, J. M.; Molinero, A.; Navarrete, J.; Oller, J. C.; Kohler, C.; Lutz, B.; Schubert, M. B.

    2006-09-04

    We present the measured performance of a new generation of semitransparente amorphous silicon position detectors. They have a large sensitive area (30 x 30 mm2) and show good properties such as a high response (about 20 mA/W), an intinsic position resolution better than 3 m, a spatial point reconstruction precision better than 10 m, deflection angles smaller than 10 rad and a transmission power in the visible and NIR higher than 70%. In addition, multipoint alignment monitoring, using up to five sensors lined along a light path of about 5 meters, can be achieved with a resolution better than 20m. (Author)

  5. Large-size high-performance transparent amorphous silicon sensors for laser beam position detection

    Energy Technology Data Exchange (ETDEWEB)

    Calderon, A. [Instituto de Fisica de Cantabria. CSIC-University of Cantabria, Santander (Spain); Martinez-Rivero, C. [Instituto de Fisica de Cantabria. CSIC-University of Cantabria, Santander (Spain); Matorras, F. [Instituto de Fisica de Cantabria. CSIC-University of Cantabria, Santander (Spain); Rodrigo, T. [Instituto de Fisica de Cantabria. CSIC-University of Cantabria, Santander (Spain); Sobron, M. [Instituto de Fisica de Cantabria. CSIC-University of Cantabria, Santander (Spain); Vila, I. [Instituto de Fisica de Cantabria. CSIC-University of Cantabria, Santander (Spain); Virto, A.L. [Instituto de Fisica de Cantabria. CSIC-University of Cantabria, Santander (Spain); Alberdi, J. [CIEMAT, Madrid (Spain); Arce, P. [CIEMAT, Madrid (Spain); Barcala, J.M. [CIEMAT, Madrid (Spain); Calvo, E. [CIEMAT, Madrid (Spain); Ferrando, A. [CIEMAT, Madrid (Spain)]. E-mail: antonio.ferrando@ciemat.es; Josa, M.I. [CIEMAT, Madrid (Spain); Luque, J.M. [CIEMAT, Madrid (Spain); Molinero, A. [CIEMAT, Madrid (Spain); Navarrete, J. [CIEMAT, Madrid (Spain); Oller, J.C. [CIEMAT, Madrid (Spain); Yuste, C. [CIEMAT, Madrid (Spain); Koehler, C. [Steinbeis-Transferzentrum fuer Angewandte Photovoltaik und Duennschichttechnik, Stuttgart (Germany); Lutz, B. [Steinbeis-Transferzentrum fuer Angewandte Photovoltaik und Duennschichttechnik, Stuttgart (Germany); Schubert, M.B. [Steinbeis-Transferzentrum fuer Angewandte Photovoltaik und Duennschichttechnik, Stuttgart (Germany); Werner, J.H. [Steinbeis-Transferzentrum fuer Angewandte Photovoltaik und Duennschichttechnik, Stuttgart (Germany)

    2006-09-15

    We present the measured performance of a new generation of semitransparent amorphous silicon position detectors. They have a large sensitive area (30x30mm{sup 2}) and show good properties such as a high response (about 20mA/W), an intrinsic position resolution better than 3{mu}m, a spatial-point reconstruction precision better than 10{mu}m, deflection angles smaller than 10{mu}rad and a transmission power in the visible and NIR higher than 70%.

  6. Large Size High Performance Transparent Amorphous Silicon Sensors for Laser Beam Position Detection and Monitoring

    International Nuclear Information System (INIS)

    Calderon, A.; Martinez Rivero, C.; Matorras, F.; Rodrigo, T.; Sobron, M.; Vila, I.; Virto; Alberdi, J.; Arce, P.; Barcala, J. M.; Calvo, E.; Ferrando, A.; Josa, M. I.; Luque, J. M.; Molinero, A.; Navarrete, J.; Oller, J. C.; Kohler, C.; Lutz, B.; Schubert, M. B.

    2006-01-01

    We present the measured performance of a new generation of semitransparente amorphous silicon position detectors. They have a large sensitive area (30 x 30 mm2) and show good properties such as a high response (about 20 mA/W), an intinsic position resolution better than 3 m, a spatial point reconstruction precision better than 10 m, deflection angles smaller than 10 rad and a transmission power in the visible and NIR higher than 70%. In addition, multipoint alignment monitoring, using up to five sensors lined along a light path of about 5 meters, can be achieved with a resolution better than 20m. (Author)

  7. The welfare implications of large litter size in the domestic pig II: management factors

    DEFF Research Database (Denmark)

    Baxter, E.M.; Rutherford, K.M.D.; D'Eath, R.B.

    2013-01-01

    routinely exceeds the ability of individual sows to successfully rear all the piglets (ie viable piglets outnumber functional teats). Such interventions include: tooth reduction; split suckling; cross-fostering; use of nurse sow systems and early weaning, including split weaning; and use of artificial...... rearing systems. These practices raise welfare questions for both the piglets and sow and are described and discussed in this review. In addition, possible management approaches which might mitigate health and welfare issues associated with large litters are identified. These include early intervention...

  8. A hybrid adaptive large neighborhood search heuristic for lot-sizing with setup times

    DEFF Research Database (Denmark)

    Muller, Laurent Flindt; Spoorendonk, Simon; Pisinger, David

    2012-01-01

    This paper presents a hybrid of a general heuristic framework and a general purpose mixed-integer programming (MIP) solver. The framework is based on local search and an adaptive procedure which chooses between a set of large neighborhoods to be searched. A mixed integer programming solver and its......, and the upper bounds found by the commercial MIP solver ILOG CPLEX using state-of-the-art MIP formulations. Furthermore, we improve the best known solutions on 60 out of 100 and improve the lower bound on all 100 instances from the literature...

  9. Herd-level risk factors for bovine viral diarrhea infection in cattle of Tamil Nadu.

    Science.gov (United States)

    Kumar, Subbiah Krishna; Palanivel, K M; Sukumar, K; Ronald, B Samuel Masilamoni; Selvaraju, G; Ponnudurai, G

    2018-04-01

    A cross-sectional study was carried out to identify risk factors for bovine viral diarrhea virus (BVDV) infection in 62 randomly selected dairy herds which were tested for BVD serum antibodies by using an indirect ELISA kit (IDEXX). Results from the chi-square test analysis were interpreted by analyzing by chi-square test. A sum of 500 sera samples were screened and 66 animals (13.20%) showed positive for BVDV antibody. Within herd, BVD seroprevalence was 12-65%. This study concluded that epidemiological risk factors like location, herd size, housing patterns like, tail to tail system, roofing pattern, distance between the manure pit and farm, and distance between farms were significantly associated with BVDV serological status (P < 0.05).

  10. Numerical modeling of deformation and vibrations in the construction of large-size fiberglass cooling tower fan

    Directory of Open Access Journals (Sweden)

    Fanisovich Shmakov Arthur

    2016-01-01

    Full Text Available This paper presents the results of numerical modeling of deformation processes and the analysis of the fundamental frequencies of the construction of large-size fiberglass cooling tower fan. Obtain the components of the stress-strain state structure based on imported gas dynamic and thermal loads and the form of fundamental vibrations. The analysis of fundamental frequencies, the results of which have been proposed constructive solutions to reduce the probability of failure of the action of aeroelastic forces.

  11. Large and abundant flowers increase indirect costs of corollas: a study of coflowering sympatric Mediterranean species of contrasting flower size.

    Science.gov (United States)

    Teixido, Alberto L; Valladares, Fernando

    2013-09-01

    Large floral displays receive more pollinator visits but involve higher production and maintenance costs. This can result in indirect costs which may negatively affect functions like reproductive output. In this study, we explored the relationship between floral display and indirect costs in two pairs of coflowering sympatric Mediterranean Cistus of contrasting flower size. We hypothesized that: (1) corolla production entails direct costs in dry mass, N and P, (2) corollas entail significant indirect costs in terms of fruit set and seed production, (3) indirect costs increase with floral display, (4) indirect costs are greater in larger-flowered sympatric species, and (5) local climatic conditions influence indirect costs. We compared fruit set and seed production of petal-removed flowers and unmanipulated control flowers and evaluated the influence of mean flower number and mean flower size on relative fruit and seed gain of petal-removed and control flowers. Fruit set and seed production were significantly higher in petal-removed flowers in all the studied species. A positive relationship was found between relative fruit gain and mean individual flower size within species. In one pair of species, fruit gain was higher in the large-flowered species, as was the correlation between fruit gain and mean number of open flowers. In the other pair, the correlation between fruit gain and mean flower size was also higher in the large-flowered species. These results reveal that Mediterranean environments impose significant constraints on floral display, counteracting advantages of large flowers from the pollination point of view with increased indirect costs of such flowers.

  12. Microstructural Control via Copious Nucleation Manipulated by In Situ Formed Nucleants: Large-Sized and Ductile Metallic Glass Composites.

    Science.gov (United States)

    Song, Wenli; Wu, Yuan; Wang, Hui; Liu, Xiongjun; Chen, Houwen; Guo, Zhenxi; Lu, Zhaoping

    2016-10-01

    A novel strategy to control the precipitation behavior of the austenitic phase, and to obtain large-sized, transformation-induced, plasticity-reinforced bulk metallic glass matrix composites, with good tensile properties, is proposed. By inducing heterogeneous nucleation of the transformable reinforcement via potent nucleants formed in situ, the characteristics of the austenitic phase are well manipulated. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Vacuum system for applying reflective coatings on large-size optical components using the method of magnetron sputtering

    Science.gov (United States)

    Azerbaev, Alexander A.; Abdulkadyrov, Magomed A.; Belousov, Sergey P.; Ignatov, Aleksandr N.; Mukhammedzyanov, Timur R.

    2016-10-01

    Vacuum system for reflective coatings deposition on large-size optical components up to 4.0 m diameter using the method of magnetron sputtering was built at JSC LZOS. The technological process for deposition of reflective Al coating with protective SiO2 layer was designed and approved. After climatic tests the lifetime of such coating was estimated as 30 years. Uniformity of coating thickness ±5% was achieved on maximum diameter 4.0 m.

  14. An analysis of herding behavior in security analysts’ networks

    Science.gov (United States)

    Zhao, Zheng; Zhang, YongJie; Feng, Xu; Zhang, Wei

    2014-11-01

    In this paper, we build undirected weighted networks to study herding behavior among analysts and to analyze the characteristics and the structure of these networks. We then construct a new indicator based on the average degree of nodes and the average weighted clustering coefficient to research the various types of herding behavior. Our findings suggest that every industry has, to a certain degree, herding behavior among analysts. While there is obvious uninformed herding behavior in real estate and certain other industries, industries such as mining and nonferrous metals have informed herding behavior caused by analysts’ similar reactions to public information. Furthermore, we relate the two types of herding behavior to stock price and find that uninformed herding behavior has a positive effect on market prices, whereas informed herding behavior has a negative effect.

  15. Herd Clustering: A synergistic data clustering approach using collective intelligence

    KAUST Repository

    Wong, Kachun; Peng, Chengbin; Li, Yue; Chan, Takming

    2014-01-01

    , this principle is used to develop a new clustering algorithm. Inspired by herd behavior, the clustering method is a synergistic approach using collective intelligence called Herd Clustering (HC). The novel part is laid in its first stage where data instances

  16. Determining the Ratio of Animal Species in the Herd of Pre-Class Societies

    Directory of Open Access Journals (Sweden)

    Stegantsev Mark A.

    2013-09-01

    Full Text Available The article is devoted to the methodology of research of domestic animals herd composition in ancient societies, based on the materials of Late Bronze and Early Iron Age sites located in the Western part of forest-steppe and steppe of Western Siberia and Northern Kazakhstan. The theoretical portion of the article demonstrates that percentage composition of the ancient herd can be restored only by taking into account the early maturation of the domestic ungulates forming its component part. The values of their early maturation depend on the distribution of animals by age. The formulas, derived through herd models developed, make it possible to determine the required distribution, based on the number of animal units of different ages in osteological collections. They are not affected by the type of herd reproduction. The application of the derived formulas in order to determine the early maturation of large and small cattle, and horses in the settlements of certain cultures in forest, forest-steppe and steppe zones, has confirmed the adequacy of the model in explaining the archaeological data. It has also been shown that economic specialization of successive Late Bronze and Early Iron Age cultures in the region was determined mainly by the horse. The study of different methods of determining ancient herd composition has made it possible to come to the following conclusion. The method of transition from identifiable bones in the excavation to the number of animal units corresponding to them, and then, by determining early maturation of different species, to their ratio in the ancient herd, has an absolute priority as compared to the method of transition from the identifiable bones directly to herd composition.

  17. The effect of herd formation among healthcare investors on health sector growth in China.

    Science.gov (United States)

    Lulin, Zhou; Antwi, Henry Asante; Wang, Wenxin; Yiranbon, Ethel; Marfo, Emmanuel Opoku; Acheampong, Patrick

    2016-07-19

    China has become the world's second largest healthcare market based on a recent report by the World Health Organization. Eventhough China achieved universal health insurance coverage in 2011, representing the largest expansion of insurance coverage in human history achieved; health inequality remains endemic in China. Lessons from the effect of market crisis on health equity in Europe and other places has reignited interest in exploring the potential healthcare market aberrations that can trigger distributive injustice in healthcare resource allocation among China's provinces. Recently, many healthcare investors in China have become more concerned about capital preservation, and are responding by abandoning long term investments strategies in healthcare. This investment withdrawal en mass is perceived to be influenced by herding tendencies and can trigger or consolidate endemic health inequality. Our study simultaneously employs four testing models (two state spaced models and two return dispersion models) to establish the existence of procyclical (herding) behavior among the stocks and its health equity implications. These are applied to a large set of data to compare and contrast results of herd formation among investors in fourteen healthcare sectors in China. The study reveals that apart from the cross sectional standard deviation (CSSD) model, the remaining two models and our augmented state space model yields significant evidence of herding in all subsectors of the healthcare market. We also find that the herding effect is more prominent during down movements of the market. Herding behavior may lead to contemporaneous loss of investor confidence and capital withdrawal and thereby deprive the healthcare sector of the much needed capital for expansion. Thus there may be obvious delay in efforts to bridge the gap in access to healthcare facilities, medical support services, medical supplies, pharmaceuticals, biotechnology, diagnostic substances, medical

  18. IMPACTS OF OWN BRANDS STRATEGY ON MANUFACTURER – RETAILER RELATIONSHIP: CASE STUDIES IN LARGE SIZE COMPANIES

    Directory of Open Access Journals (Sweden)

    Renato Telles

    2012-05-01

    Full Text Available The study of marketing and production strategy of own brand products requires an understanding of both the benefits gained by retailers and manufacturers involved in this activity and also the effects of this strategy on the relationship between these companies. According to this idea, a qualitative and descriptive work was conducted, based on six case studies, three of them on large product manufacturers and three on large retailers. The aim of this study is defined is threefold: (1 to analyze the expectations of manufacturers and retailers with their own brands’ current operations, (2 to analyze the expectations of manufacturers and retailers with their own brands’ future operations, and (3 to analyze the influence of the own brands adoption on the relationship between manufacturers and retailers. The results indicate that (a current operations are primarily based on economic reasons (market share, and use of spare capacity, (b future operations are perceived from a marketing perspective (survival, and (c the adoption of own brand strategy does not harm the relationship between the parties – both manufacturers and retailers –, unlike the earlier studies indicated.

  19. Desorption of large molecules with light-element clusters: Effects of cluster size and substrate nature

    Energy Technology Data Exchange (ETDEWEB)

    Delcorte, Arnaud, E-mail: arnaud.delcorte@uclouvain.be [Institute of Condensed Matter and Nanosciences - Bio and Soft Matter, Universite catholique de Louvain, Croix du Sud, 1 bte 3, B-1348 Louvain-la-Neuve (Belgium); Garrison, Barbara J. [Department of Chemistry, Penn State University, University Park, PA 16802 (United States)

    2011-07-15

    This contribution focuses on the conditions required to desorb a large hydrocarbon molecule using light-element clusters. The test molecule is a 7.5 kDa coil of polystyrene (PS61). Several projectiles are compared, from C{sub 60} to 110 kDa organic droplets and two substrates are used, amorphous polyethylene and mono-crystalline gold. Different aiming points and incidence angles are examined. Under specific conditions, 10 keV nanodrops can desorb PS61 intact from a gold substrate and from a soft polyethylene substrate. The prevalent mechanism for the desorption of intact and 'cold' molecules is one in which the molecules are washed away by the projectile constituents and entrained in their flux, with an emission angle close to {approx}70 deg. The effects of the different parameters on the dynamics and the underlying physics are discussed in detail and the predictions of the model are compared with other published studies.

  20. Desorption of large molecules with light-element clusters: Effects of cluster size and substrate nature

    International Nuclear Information System (INIS)

    Delcorte, Arnaud; Garrison, Barbara J.

    2011-01-01

    This contribution focuses on the conditions required to desorb a large hydrocarbon molecule using light-element clusters. The test molecule is a 7.5 kDa coil of polystyrene (PS61). Several projectiles are compared, from C 60 to 110 kDa organic droplets and two substrates are used, amorphous polyethylene and mono-crystalline gold. Different aiming points and incidence angles are examined. Under specific conditions, 10 keV nanodrops can desorb PS61 intact from a gold substrate and from a soft polyethylene substrate. The prevalent mechanism for the desorption of intact and 'cold' molecules is one in which the molecules are washed away by the projectile constituents and entrained in their flux, with an emission angle close to ∼70 deg. The effects of the different parameters on the dynamics and the underlying physics are discussed in detail and the predictions of the model are compared with other published studies.

  1. Size matters: the ethical, legal, and social issues surrounding large-scale genetic biobank initiatives

    Directory of Open Access Journals (Sweden)

    Klaus Lindgaard Hoeyer

    2012-04-01

    Full Text Available During the past ten years the complex ethical, legal and social issues (ELSI typically surrounding large-scale genetic biobank research initiatives have been intensely debated in academic circles. In many ways genetic epidemiology has undergone a set of changes resembling what in physics has been called a transition into Big Science. This article outlines consequences of this transition and suggests that the change in scale implies challenges to the roles of scientists and public alike. An overview of key issues is presented, and it is argued that biobanks represent not just scientific endeavors with purely epistemic objectives, but also political projects with social implications. As such, they demand clever maneuvering among social interests to succeed.

  2. MMSW. A large-size micromegas quadruplet prototype. Design and construction

    Energy Technology Data Exchange (ETDEWEB)

    Kuger, Fabian; Sidiropoulou, Ourania [Julius Maximilians Universitaet, Wuerzburg (Germany); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Bianco, Michele; Danielsson, Hans; Degrange, Jordan; Oliveira, Rui de; Farina, Eduardo; Iengo, Paolo; Perez Gomez, Francisco; Sekhniaidze, Givi; Sforza, Federico; Vergain, Maurice; Wotschack, Joerg [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Duedder, Andreas; Lin, Tai-Hua; Schott, Matthias [Johannes Gutenberg-Universitaet, Mainz (Germany)

    2016-07-01

    Two micromegas detector quadruplets with an area of 0.5 m{sup 2} (MMSW) have been recently constructed and tested at CERN and University of Mainz. They serve as prototypes for the planned upgrade project of the ATLAS muon system. Their design is based on the resistive-strip technology and thus renders the detectors spark tolerant. The applied 'mechanically floating' mesh design allows for large area Micromegas construction and facilitates detector cleaning before assembly. Each quadruplet comprises four detection layers with 1024 readout strips and a strip pitch of 415 μm. In two out of the four layers the strips are inclined by ± 1.5 to allow for the measurement of a second coordinate. We present the detector concept and report on the experience gained during the detector construction.

  3. Assessing animal welfare in sow herds using data on meat inspection, medication and mortality.

    Science.gov (United States)

    Knage-Rasmussen, K M; Rousing, T; Sørensen, J T; Houe, H

    2015-03-01

    This paper aims to contribute to the development of a cost-effective alternative to expensive on-farm animal-based welfare assessment systems. The objective of the study was to design an animal welfare index based on central database information (DBWI), and to validate it against an animal welfare index based on-farm animal-based measurements (AWI). Data on 63 Danish sow herds with herd-sizes of 80 to 2500 sows and an average herd size of 501 were collected from three central databases containing: Meat inspection data collected at animal level in the abattoir, mortality data at herd level from the rendering plants of DAKA, and medicine records at both herd and animal group level (sow with piglets, weaners or finishers) from the central database Vetstat. Selected measurements taken from these central databases were used to construct the DBWI. The relative welfare impacts of both individual database measurements and the databases overall were assigned in consultation with a panel consisting of 12 experts. The experts were drawn from production advisory activities, animal science and in one case an animal welfare organization. The expert panel weighted each measurement on a scale from 1 (not-important) to 5 (very important). The experts also gave opinions on the relative weightings of measurements for each of the three databases by stating a relative weight of each database in the DBWI. On the basis of this, the aggregated DBWI was normalized. The aggregation of AWI was based on weighted summary of herd prevalence's of 20 clinical and behavioural measurements originating from a 1 day data collection. AWI did not show linear dependency of DBWI. This suggests that DBWI is not suited to replace an animal welfare index using on-farm animal-based measurements.

  4. A polymer, random walk model for the size-distribution of large DNA fragments after high linear energy transfer radiation

    Science.gov (United States)

    Ponomarev, A. L.; Brenner, D.; Hlatky, L. R.; Sachs, R. K.

    2000-01-01

    DNA double-strand breaks (DSBs) produced by densely ionizing radiation are not located randomly in the genome: recent data indicate DSB clustering along chromosomes. Stochastic DSB clustering at large scales, from > 100 Mbp down to simulations and analytic equations. A random-walk, coarse-grained polymer model for chromatin is combined with a simple track structure model in Monte Carlo software called DNAbreak and is applied to data on alpha-particle irradiation of V-79 cells. The chromatin model neglects molecular details but systematically incorporates an increase in average spatial separation between two DNA loci as the number of base-pairs between the loci increases. Fragment-size distributions obtained using DNAbreak match data on large fragments about as well as distributions previously obtained with a less mechanistic approach. Dose-response relations, linear at small doses of high linear energy transfer (LET) radiation, are obtained. They are found to be non-linear when the dose becomes so large that there is a significant probability of overlapping or close juxtaposition, along one chromosome, for different DSB clusters from different tracks. The non-linearity is more evident for large fragments than for small. The DNAbreak results furnish an example of the RLC (randomly located clusters) analytic formalism, which generalizes the broken-stick fragment-size distribution of the random-breakage model that is often applied to low-LET data.

  5. E-herding : patterns of online mass-behavior

    NARCIS (Netherlands)

    Langley, D.J.; Hoeve, M.; Ortt, J.R.; Pals, N.

    2012-01-01

    Herding is convergent social behavior driven by inter-personal interaction, without centralized coordination. Herding in the online setting, which we call e-herding, is important for marketing scholars and practitioners because of its potential impact on product adoption and brand image and because

  6. Forecasting Housing Approvals in Australia: Do Forecasters Herd?

    DEFF Research Database (Denmark)

    Stadtmann, Georg; Pierdzioch; Rülke

    2012-01-01

    Price trends in housing markets may reflect herding of market participants. A natural question is whether such herding, to the extent that it occurred, reflects herding in forecasts of professional forecasters. Using more than 6,000 forecasts of housing approvals for Australia, we did not find...

  7. 9 CFR 77.36 - Interstate movement from qualified herds.

    Science.gov (United States)

    2010-01-01

    ... date of movement. If a group of captive cervids from a qualified herd is being moved interstate... unclassified herd. (4) Captive cervids being moved interstate for the purpose of exhibition only may be moved... being moved directly from a classified herd, the captive cervid must be isolated from all other animals...

  8. Aspects of bovine herpesvirus-1 infection in dairy and beef herds in the Republic of Ireland

    Directory of Open Access Journals (Sweden)

    Doherty Michael L

    2011-06-01

    Full Text Available Abstract Background Infection with bovine herpesvirus-1 (BHV-1 causes a wide range of disease manifestations, including respiratory disease and abortion, with world-wide distribution. The primary objective of the present study was to describe aspects of BHV-1 infection and control on Irish farms, including herd-level seroprevalence (based on pooled sera and vaccine usage. Methods The characteristics of a diagnostic indirect BHV-1 antibody ELISA test when used on serum pools were evaluated using laboratory replicates for use in the seroprevalence study. The output from this indirect ELISA was expressed as a percentage positivity (PP value. A proposed cut off (PCO PP was applied in a cross-sectional study of a stratified random sample of 1,175 Irish dairy and beef cattle herds in 2009, using serum pools, to estimate herd seroprevalence. The study was observational, based primarily on the analysis of existing samples, and only aggregated results were reported. For these reasons, ethical approval was not required. Bulk milk samples from a subset of 111 dairy herds were analysed using the same ELISA. Information regarding vaccine usage was determined in a telephone survey. Results A PCO PP of 7.88% was determined to give 97.1% sensitivity and 100% specificity relative to the use of the ELISA on individual sera giving maximization of the prevalence independent Youden's index, on receiver operating characteristics analysis of replicate results. The herd-level BHV-1 seroprevalence was 74.9% (95% CI - 69.9%-79.8%, with no significant difference between dairy and beef herds. 95.5% agreement in herd classification was found between bulk milk and serum pools. Only 1.8 percent of farmers used BHV-1 marker vaccine, 80% of which was live while 75% of vaccinated herds were dairy. A significant association was found between herd size (quartiles and seroprevalence (quartiles. Conclusions The results from this study indicate BHV-1 infection is endemic, although

  9. INNOVATIVE TECHNIQUES AND TECHNOLOGY APPLICATION IN MANAGEMENT OF REMOTE HANDLED AND LARGE SIZED MIXED WASTE FORMS

    International Nuclear Information System (INIS)

    BLACKFORD LT

    2008-01-01

    CH2M HILL Hanford Group, Inc. (CH2M HILL) plays a critical role in Hanford Site cleanup for the U. S. Department of Energy, Office of River Protection (ORP). CH2M HILL is responsible for the management of 177 tanks containing 53 million gallons of highly radioactive wastes generated from weapons production activities from 1943 through 1990. In that time, 149 single-shell tanks, ranging in capacity from 50,000 gallons to 500,000 gallons, and 28 double-shell tanks with a capacity of 1 million gallons each, were constructed and filled with toxic liquid wastes and sludges. The cleanup mission includes removing these radioactive waste solids from the single-shell tanks to double-shell tanks for staging as feed to the Waste Treatment Plant (WTP) on the Hanford Site for vitrification of the wastes and disposal on the Hanford Site and Yucca Mountain repository. Concentrated efforts in retrieving residual solid and sludges from the single-shell tanks began in 2003; the first tank retrieved was C-106 in the 200 East Area of the site. The process for retrieval requires installation of modified sluicing systems, vacuum systems, and pumping systems into existing tank risers. Inherent with this process is the removal of existing pumps, thermo-couples, and agitating and monitoring equipment from the tank to be retrieved. Historically, these types of equipment have been extremely difficult to manage from the aspect of radiological dose, size, and weight of the equipment, as well as their attendant operating and support systems such as electrical distribution and control panels, filter systems, and mobile retrieval systems. Significant effort and expense were required to manage this new waste stream and resulted in several events over time that were both determined to be unsafe for workers and potentially unsound for protection of the environment. Over the last four years, processes and systems have been developed that reduce worker exposures to these hazards, eliminate violations

  10. Study of the pressing operation of large-sized tiles using X-ray absorption

    International Nuclear Information System (INIS)

    Amoros, J. L.; Mallol, G.; Llorens, D.; Boix, J.; Arnau, J. M.; Feliu, C.; Cerisuelo, J. A.; Gargallo, J. J.

    2010-01-01

    An apparatus for X-Ray non destructive inspection of bulk density distribution in large ceramic tiles has been designed, built and patented. This technique has many advantages compared with other methods: it allows tile bulk density distribution to be mapped and is neither destructive nor toxic, provided the X-ray tube and detector area are shielded to prevent leakage. In the present study, this technique, whose technical feasibility and accuracy had been verified in previous studies, has been used to scan ceramic tiles formed under different industrial conditions, modifying press working parameters. The use of high-precision laser telemeters allows tile thicknesses to be mapped, facilitating the interpretation of manufacturing defects produced in pressing, which cannot be interpreted by just measuring bulk density. The bulk density distributions obtained in the same unfired and fired tiles are also compared, a possibility afforded only by this measurement method, since it is non-destructive. The comparison of both unfired and fired tile bulk density distributions allows the influence of the pressing and firing stages on tile end porosity to be individually identified. (Author) 12 refs.

  11. Theory of resistive magnetohydrodynamic instabilities excited by energetic trapped particles in large-size tokamaks

    International Nuclear Information System (INIS)

    Biglari, H.

    1987-01-01

    A theory describing excitation of resistive magnetohydrodynamic instabilities due to a population of energetic particles, trapped in region of adverse curvature on energetic particles, trapped in region of adverse curvature in tokamaks, is presented. Theory's principal motivation is observation that high magnetic-field strengths and large geometric dimensions characteristic of present-generation thermonuclear fusion devices, places them in a frequency regime whereby processional drift frequency of auxiliary hot-ion species, in order of magnitude, falls below a typical inverse resistive interchange time scale, so that inclusion of resistive dissipation effects becomes important. Destabilization of the resistive internal kink mode by these suprathermal particles is first investigated. Using variational techniques, a generalized dispersion relation governing such modes, which recovers ideal theory in its appropriate limit, is derived and analyzed using Nyquist-diagrammatic techniques. An important implication of theory for present-generation fusion devices is that they will be stable to fishbone activity. Interaction of energetic particles with resistive interchange-ballooning modes is taken up. A population of hot particles, deeply trapped on adverse curvature side in tokamaks, can resonantly destabilize resistive interchange mode, which is stable in their absence because of favorable average curvature. Both modes are different from their usual resistive magnetohydrodynamic counterparts in their destabilization mechanism

  12. Design and Construction of Large Size Micromegas Chambers for the ATLAS Upgrade of the Muon Spectrometer

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00380308; The ATLAS collaboration

    2016-01-01

    Large area Micromegas detectors will be employed for the first time in high-energy physics experiments. A total surface area of about 150 m$^2$ of the forward regions (pseudo-rapidity coverage -- 1.3 $\\boldsymbol{< |\\eta| <}$ 2.7) of the Muon Spectrometer of the ATLAS detector at LHC will be equipped with 8-layer Micromegas modules. Each module extends over a surface from 2 to 3 m$^2$ for a total active area of 1200 m$^2$. Together with the small strip Thin Gap Chambers they will compose the two New Small Wheels (NSW), which will replace the innermost stations of the ATLAS endcap muon tracking system in the 2018/19 shutdown. In order to achieve a 15\\% transverse momentum resolution for 1 TeV muons, in addition to an excellent intrinsic position resolution, the mechanical precision of each plane of the assembled module must be $\\boldsymbol{30{\\mu}m}$ along the precision coordinate and $\\boldsymbol{80{\\mu}m}$ perpendicular to the chamber. All readout planes are segmented into strips with a pitch of $\\bold...

  13. Design and Construction of Large Size Micromegas Chambers for the ATLAS Upgrade of the Muon Spectrometer

    CERN Document Server

    Jeanneau, Fabien; The ATLAS collaboration

    2015-01-01

    Large area Micromegas detectors will be employed for the first time in high-energy physics experiments. A total surface of about 150 m2 of the forward regions of the Muon Spectrometer of the ATLAS detector at LHC will be equipped with 8-layer Micromegas modules. Each module extends over a surface from 2 to 3 m2 for a total active area of 1200 m2. Together with the small strip Thin Gap Chambers they will compose the two New Small Wheels, which will replace the innermost stations of the ATLAS endcap muon tracking system in the 2018/19 shutdown. In order to achieve a 15% transverse momentum resolution for 1 TeV muons, in addition to an excellent intrinsic resolution, the mechanical precision of each plane of the assembled module must be as good as 30 μm along the precision coordinate and 80 μm perpendicular to the chamber. In the prototyping towards the final configuration two similar quadruplets with dimensions 1.2×0.5 m2 have been built with the same structure as foreseen for the NSW upgrade. It represents ...

  14. Design and Construction of Large Size Micromegas Chambers for the ATLAS Upgrade of the Muon Spectrometer

    CERN Document Server

    Jeanneau, Fabien; The ATLAS collaboration

    2015-01-01

    Large area Micromegas detectors will be employed for the first time in high-energy physics experiments. A total surface of about 150 m2 of the forward regions of the Muon Spectrometer of the ATLAS detector at LHC will be equipped with 8-layer Micromegas modules. Each module extends over a surface from 2 to 3 m2 for a total active area of 1200 m2. Together with the small strip Thin Gap Chambers they will compose the two New Small Wheels, which will replace the innermost stations of the ATLAS endcap muon tracking system in the 2018/19 shutdown. In order to achieve a 15% transverse momentum resolution for 1 TeV muons, in addition to an excellent intrinsic resolution, the mechanical precision of each plane of the assembled module must be as good as 30 μm along the precision coordinate and 80 μm perpendicular to the chamber. All readout planes are segmented into strips with a pitch of 400 μm for a total of 4096 strips. In two of the four planes the strips are inclined by 1.5 ◦ and provide a measurement of the...

  15. Design and Construction of Large Size Micromegas Chambers for the Upgrade of the ATLAS Muon Spectrometer

    CERN Document Server

    Lösel, Philipp; Müller, Ralph

    2015-01-01

    Large area Micromegas detectors will be employed for the first time in high-energy physics experiments. A total surface of about $\\mathbf{150~m^2}$ of the forward regions of the Muon Spectrometer of the ATLAS detector at LHC will be equipped with 8-layer Micromegas modules. Each layer covers more than $\\mathbf{2~m^2}$ for a total active area of $\\mathbf{1200~m^2}$. Together with the small strip Thin Gap Chambers they will compose the two New Small Wheels, which will replace the innermost stations of the ATLAS endcap muon tracking system in the 2018/19 shutdown. In order to achieve a 15$\\mathbf{\\%}$ transverse momentum resolution for $\\mathbf{1~TeV}$ muons, in addition to an excellent intrinsic resolution, the mechanical precision of each plane of the assembled module must be as good as $\\mathbf{30~\\mu m}$ along the precision coordinate and $\\mathbf{80~\\mu m}$ perpendicular to the chamber. The design and construction procedure of the Micromegas modules will be presented, as well as the design for the assembly ...

  16. Design and Construction of Large Size Micromegas Chambers for the ATLAS Upgrade of the Muon Spectrometer

    CERN Document Server

    Losel, Philipp Jonathan; The ATLAS collaboration

    2014-01-01

    Large area Micromegas detectors will be employed fo r the first time in high-energy physics experiments. A total surface of about 150 m$^2$ of the forward regions of the Muon Spectrometer of the ATLAS detector at LHC will be equipped with 8-layer Micromegas modules. Each module extends over a surface from 2 to 3 m$^2$ for a total active area of 1200 m$^2$. Together with the small strip Thin Gap Chambers they will compose the two New Small Wheels, which will replace the innermost stations of the ATLAS endcap muon tracking system in the 2018/19 shutdown. In order to achieve a 15% transverse momentum resol ution for 1 TeV muons, in addition to an excellent intrinsic resolution, the mechanical prec ision of each plane of the assembled module must be as good as 30 $\\mu$m along the precision coordi nate and 80 $\\mu$m perpendicular to the chamber. The design and construction procedure of the microm egas modules will be presented, as well as the design for the assembly of modules onto the New Small Wheel. Emphasis wi...

  17. Simulation of reflecting surface deviations of centimeter-band parabolic space radiotelescope (SRT) with the large-size mirror

    Science.gov (United States)

    Kotik, A.; Usyukin, V.; Vinogradov, I.; Arkhipov, M.

    2017-11-01

    he realization of astrophysical researches requires the development of high-sensitive centimeterband parabolic space radiotelescopes (SRT) with the large-size mirrors. Constructively such SRT with the mirror size more than 10 m can be realized as deployable rigid structures. Mesh-structures of such size do not provide the reflector reflecting surface accuracy which is necessary for the centimeter band observations. Now such telescope with the 10 m diameter mirror is developed in Russia in the frame of "SPECTR - R" program. External dimensions of the telescope is more than the size of existing thermo-vacuum chambers used to prove SRT reflecting surface accuracy parameters under the action of space environment factors. That's why the numerical simulation turns out to be the basis required to accept the taken designs. Such modeling should be based on experimental working of the basic constructive materials and elements of the future reflector. In the article computational modeling of reflecting surface deviations of a centimeter-band of a large-sized deployable space reflector at a stage of his orbital functioning is considered. The analysis of the factors that determines the deviations - both determined (temperatures fields) and not-determined (telescope manufacturing and installation faults; the deformations caused by features of composite materials behavior in space) is carried out. The finite-element model and complex of methods are developed. They allow to carry out computational modeling of reflecting surface deviations caused by influence of all factors and to take into account the deviations correction by space vehicle orientation system. The results of modeling for two modes of functioning (orientation at the Sun) SRT are presented.

  18. When David beats Goliath: the advantage of large size in interspecific aggressive contests declines over evolutionary time.

    Directory of Open Access Journals (Sweden)

    Paul R Martin

    Full Text Available Body size has long been recognized to play a key role in shaping species interactions. For example, while small species thrive in a diversity of environments, they typically lose aggressive contests for resources with larger species. However, numerous examples exist of smaller species dominating larger species during aggressive interactions, suggesting that the evolution of traits can allow species to overcome the competitive disadvantage of small size. If these traits accumulate as lineages diverge, then the advantage of large size in interspecific aggressive interactions should decline with increased evolutionary distance. We tested this hypothesis using data on the outcomes of 23,362 aggressive interactions among 246 bird species pairs involving vultures at carcasses, hummingbirds at nectar sources, and antbirds and woodcreepers at army ant swarms. We found the advantage of large size declined as species became more evolutionarily divergent, and smaller species were more likely to dominate aggressive contests when interacting with more distantly-related species. These results appear to be caused by both the evolution of traits in smaller species that enhanced their abilities in aggressive contests, and the evolution of traits in larger species that were adaptive for other functions, but compromised their abilities to compete aggressively. Specific traits that may provide advantages to small species in aggressive interactions included well-developed leg musculature and talons, enhanced flight acceleration and maneuverability, novel fighting behaviors, and traits associated with aggression, such as testosterone and muscle development. Traits that may have hindered larger species in aggressive interactions included the evolution of morphologies for tree trunk foraging that compromised performance in aggressive contests away from trunks, and the evolution of migration. Overall, our results suggest that fundamental trade-offs, such as those

  19. Separation of large DNA molecules by applying pulsed electric field to size exclusion chromatography-based microchip

    Science.gov (United States)

    Azuma, Naoki; Itoh, Shintaro; Fukuzawa, Kenji; Zhang, Hedong

    2018-02-01

    Through electrophoresis driven by a pulsed electric field, we succeeded in separating large DNA molecules with an electrophoretic microchip based on size exclusion chromatography (SEC), which was proposed in our previous study. The conditions of the pulsed electric field required to achieve the separation were determined by numerical analyses using our originally proposed separation model. From the numerical results, we succeeded in separating large DNA molecules (λ DNA and T4 DNA) within 1600 s, which was approximately half of that achieved under a direct electric field in our previous study. Our SEC-based electrophoresis microchip will be one of the effective tools to meet the growing demand of faster and more convenient separation of large DNA molecules, especially in the field of epidemiological research of infectious diseases.

  20. Herd- and sow-related risk factors for lameness in organic and conventional sow herds

    DEFF Research Database (Denmark)

    Knage-Rasmussen, Kristian Møllegaard; Houe, Hans; Rousing, Tine

    2014-01-01

    included in the study were clinical parameters and factors related to the production system. Sows were examined visually by one of four trained observers. The organic sows were assigned scores for lameness, body condition, hoof length, bursitis, abscesses and leg wounds, while the conventional sows were...... assigned scores for lameness, body condition and bursitis. A multivariable analysis was carried out by logistic regression with the herd and observer as random effects. The average herd lameness prevalence in gestation and lactation sows in organic herds was 11% in summer/autumn and 4.6% in winter....../spring. ‘Wounds, bursitis and abscess’ on legs (OR=4.7, P3 (OR=1.79, P=0.008) were associated with increased risk of lameness in Danish organic sow herds. Season (winter/spring v. summer/autumn) lowered the risk of lameness (OR=0.37, P

  1. Multiscale virtual particle based elastic network model (MVP-ENM) for normal mode analysis of large-sized biomolecules.

    Science.gov (United States)

    Xia, Kelin

    2017-12-20

    In this paper, a multiscale virtual particle based elastic network model (MVP-ENM) is proposed for the normal mode analysis of large-sized biomolecules. The multiscale virtual particle (MVP) model is proposed for the discretization of biomolecular density data. With this model, large-sized biomolecular structures can be coarse-grained into virtual particles such that a balance between model accuracy and computational cost can be achieved. An elastic network is constructed by assuming "connections" between virtual particles. The connection is described by a special harmonic potential function, which considers the influence from both the mass distributions and distance relations of the virtual particles. Two independent models, i.e., the multiscale virtual particle based Gaussian network model (MVP-GNM) and the multiscale virtual particle based anisotropic network model (MVP-ANM), are proposed. It has been found that in the Debye-Waller factor (B-factor) prediction, the results from our MVP-GNM with a high resolution are as good as the ones from GNM. Even with low resolutions, our MVP-GNM can still capture the global behavior of the B-factor very well with mismatches predominantly from the regions with large B-factor values. Further, it has been demonstrated that the low-frequency eigenmodes from our MVP-ANM are highly consistent with the ones from ANM even with very low resolutions and a coarse grid. Finally, the great advantage of MVP-ANM model for large-sized biomolecules has been demonstrated by using two poliovirus virus structures. The paper ends with a conclusion.

  2. Investigating the Variability in Cumulus Cloud Number as a Function of Subdomain Size and Organization using large-domain LES

    Science.gov (United States)

    Neggers, R.

    2017-12-01

    Recent advances in supercomputing have introduced a "grey zone" in the representation of cumulus convection in general circulation models, in which this process is partially resolved. Cumulus parameterizations need to be made scale-aware and scale-adaptive to be able to conceptually and practically deal with this situation. A potential way forward are schemes formulated in terms of discretized Cloud Size Densities, or CSDs. Advantages include i) the introduction of scale-awareness at the foundation of the scheme, and ii) the possibility to apply size-filtering of parameterized convective transport and clouds. The CSD is a new variable that requires closure; this concerns its shape, its range, but also variability in cloud number that can appear due to i) subsampling effects and ii) organization in a cloud field. The goal of this study is to gain insight by means of sub-domain analyses of various large-domain LES realizations of cumulus cloud populations. For a series of three-dimensional snapshots, each with a different degree of organization, the cloud size distribution is calculated in all subdomains, for a range of subdomain sizes. The standard deviation of the number of clouds of a certain size is found to decrease with the subdomain size, following a powerlaw scaling corresponding to an inverse-linear dependence. Cloud number variability also increases with cloud size; this reflects that subsampling affects the largest clouds first, due to their typically larger neighbor spacing. Rewriting this dependence in terms of two dimensionless groups, by dividing by cloud number and cloud size respectively, yields a data collapse. Organization in the cloud field is found to act on top of this primary dependence, by enhancing the cloud number variability at the smaller sizes. This behavior reflects that small clouds start to "live" on top of larger structures such as cold pools, favoring or inhibiting their formation (as illustrated by the attached figure of cloud mask

  3. Inferring Population Size History from Large Samples of Genome-Wide Molecular Data - An Approximate Bayesian Computation Approach.

    Directory of Open Access Journals (Sweden)

    Simon Boitard

    2016-03-01

    Full Text Available Inferring the ancestral dynamics of effective population size is a long-standing question in population genetics, which can now be tackled much more accurately thanks to the massive genomic data available in many species. Several promising methods that take advantage of whole-genome sequences have been recently developed in this context. However, they can only be applied to rather small samples, which limits their ability to estimate recent population size history. Besides, they can be very sensitive to sequencing or phasing errors. Here we introduce a new approximate Bayesian computation approach named PopSizeABC that allows estimating the evolution of the effective population size through time, using a large sample of complete genomes. This sample is summarized using the folded allele frequency spectrum and the average zygotic linkage disequilibrium at different bins of physical distance, two classes of statistics that are widely used in population genetics and can be easily computed from unphased and unpolarized SNP data. Our approach provides accurate estimations of past population sizes, from the very first generations before present back to the expected time to the most recent common ancestor of the sample, as shown by simulations under a wide range of demographic scenarios. When applied to samples of 15 or 25 complete genomes in four cattle breeds (Angus, Fleckvieh, Holstein and Jersey, PopSizeABC revealed a series of population declines, related to historical events such as domestication or modern breed creation. We further highlight that our approach is robust to sequencing errors, provided summary statistics are computed from SNPs with common alleles.

  4. Design and Construction of Large Size Micromegas Chambers for the ATLAS Upgrade of the Muon Spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-07-01

    Large area Micromegas detectors will be employed for the first time in high-energy physics experiments. A total surface of about 150 m{sup 2} of the forward regions of the Muon Spectrometer of the ATLAS detector at LHC will be equipped with 8-layer Micromegas modules. Each module extends over a surface from 2 to 3 m{sup 2} for a total active area of 1200 m{sup 2}. Together with the small strip Thin Gap Chambers they will compose the two New Small Wheels, which will replace the innermost stations of the ATLAS end-cap muon tracking system in the 2018/19 shutdown. In order to achieve a 15% transverse momentum resolution for 1 TeV muons, in addition to an excellent intrinsic resolution, the mechanical precision of each plane of the assembled module must be as good as 30 μm along the precision coordinate and 80 μm perpendicular to the chamber. In the prototyping towards the final configuration two similar quadruplets with dimensions 1.2 x 0.5 m{sup 2} have been built with the same structure as foreseen for the NSW upgrade. It represents the first example of a Micromegas quadruplet ever built, realized using the resistive-strip technology and decoupling the amplification mesh from the readout structure. All readout planes are segmented into strips with a pitch of 400 μm for a total of 4096 strips. In two of the four planes the strips are inclined by 1.5 deg. and provide a measurement of the second coordinate. The design and construction procedure of the Micromegas modules will be presented, as well as the design for the assembly of modules onto the New Small Wheel. Emphasis will be given on the methods developed to achieve the challenging mechanical precision. Measurements of deformation on chamber prototypes as a function of thermal gradients, gas over-pressure and internal stress (mesh tension and module fixation on supports) will be also shown in comparison to simulation. These tests were essential in the development of the final design in order to minimize the

  5. Efficient inference of population size histories and locus-specific mutation rates from large-sample genomic variation data.

    Science.gov (United States)

    Bhaskar, Anand; Wang, Y X Rachel; Song, Yun S

    2015-02-01

    With the recent increase in study sample sizes in human genetics, there has been growing interest in inferring historical population demography from genomic variation data. Here, we present an efficient inference method that can scale up to very large samples, with tens or hundreds of thousands of individuals. Specifically, by utilizing analytic results on the expected frequency spectrum under the coalescent and by leveraging the technique of automatic differentiation, which allows us to compute gradients exactly, we develop a very efficient algorithm to infer piecewise-exponential models of the historical effective population size from the distribution of sample allele frequencies. Our method is orders of magnitude faster than previous demographic inference methods based on the frequency spectrum. In addition to inferring demography, our method can also accurately estimate locus-specific mutation rates. We perform extensive validation of our method on simulated data and show that it can accurately infer multiple recent epochs of rapid exponential growth, a signal that is difficult to pick up with small sample sizes. Lastly, we use our method to analyze data from recent sequencing studies, including a large-sample exome-sequencing data set of tens of thousands of individuals assayed at a few hundred genic regions. © 2015 Bhaskar et al.; Published by Cold Spring Harbor Laboratory Press.

  6. Small genomes and large seeds: chromosome numbers, genome size and seed mass in diploid Aesculus species (Sapindaceae).

    Science.gov (United States)

    Krahulcová, Anna; Trávnícek, Pavel; Krahulec, František; Rejmánek, Marcel

    2017-04-01

    Aesculus L. (horse chestnut, buckeye) is a genus of 12-19 extant woody species native to the temperate Northern Hemisphere. This genus is known for unusually large seeds among angiosperms. While chromosome counts are available for many Aesculus species, only one has had its genome size measured. The aim of this study is to provide more genome size data and analyse the relationship between genome size and seed mass in this genus. Chromosome numbers in root tip cuttings were confirmed for four species and reported for the first time for three additional species. Flow cytometric measurements of 2C nuclear DNA values were conducted on eight species, and mean seed mass values were estimated for the same taxa. The same chromosome number, 2 n = 40, was determined in all investigated taxa. Original measurements of 2C values for seven Aesculus species (eight taxa), added to just one reliable datum for A. hippocastanum , confirmed the notion that the genome size in this genus with relatively large seeds is surprisingly low, ranging from 0·955 pg 2C -1 in A. parviflora to 1·275 pg 2C -1 in A. glabra var. glabra. The chromosome number of 2 n = 40 seems to be conclusively the universal 2 n number for non-hybrid species in this genus. Aesculus genome sizes are relatively small, not only within its own family, Sapindaceae, but also within woody angiosperms. The genome sizes seem to be distinct and non-overlapping among the four major Aesculus clades. These results provide an extra support for the most recent reconstruction of Aesculus phylogeny. The correlation between the 2C values and seed masses in examined Aesculus species is slightly negative and not significant. However, when the four major clades are treated separately, there is consistent positive association between larger genome size and larger seed mass within individual lineages. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For

  7. Nation-wide Salmonella enterica surveillance and control in Danish slaughter swine herds

    DEFF Research Database (Denmark)

    Mousing, Jan; Jensen, P.T.; Halgaard, C.

    1997-01-01

    ranging from four to more than 60 swine are obtained quarterly at the abattoir. A meat sample from each pig is frozen, and meat juice (harvested after thawing) is examined for specific antibodies against S. enterica using an indirect enzyme-linked immunosorbent assay (ELISA). The ELISA combines several S...... during 1995 ranged from a mean of 2.9% in smaller herds (101-200 swine slaughtered per year) to 6.1% in relatively large herds (more than 5000 swine slaughtered per year)....

  8. House Price Forecasts, Forecaster Herding, and the Recent Crisis

    Directory of Open Access Journals (Sweden)

    Christian Pierdzioch

    2012-11-01

    Full Text Available We used the Wall Street Journal survey data for the period 2006–2012 to analyze whether forecasts of house prices and housing starts provide evidence of (anti-herding of forecasters. Forecasts are consistent with herding (anti-herding of forecasters if forecasts are biased towards (away from the consensus forecast. We found that anti-herding is prevalent among forecasters of house prices. We also report that, following the recent crisis, the prevalence of forecaster anti-herding seems to have changed over time.

  9. House Price Forecasts, Forecaster Herding, and the Recent Crisis

    DEFF Research Database (Denmark)

    Stadtmann, Georg; Pierdzioch; Ruelke

    2013-01-01

    We used the Wall Street Journal survey data for the period 2006–2012 to analyze whether forecasts of house prices and housing starts provide evidence of (anti-)herding of forecasters. Forecasts are consistent with herding (anti-herding) of forecasters if forecasts are biased towards (away from) t......) the consensus forecast. We found that anti-herding is prevalent among forecasters of house prices. We also report that, following the recent crisis, the prevalence of forecaster anti-herding seems to have changed over time....

  10. Covariance functions across herd production levels for test day records on milk, fat, and protein yields

    NARCIS (Netherlands)

    Veerkamp, R.F.; Goddard, M.E.

    1998-01-01

    Multiple-trait BLUP evaluations of test day records require a large number of genetic parameters. This study estimated covariances with a reduced model that included covariance functions in two dimensions (stage of lactation and herd production level) and all three yield traits. Records came from

  11. Evaluation of intestinal sampling sites in pigs at slaughter for assessing antibiotic resistance level in swine herds

    DEFF Research Database (Denmark)

    Jensen, Annette Nygaard; Thanou, Olga; Axelsdottir, Aslaug

    2012-01-01

    to at each individual herd would reduce the work load and costs significantly. However, due to the potential oral exposure to bacteria in the environment during transport and lairage of pigs, intestinal content sampled at the slaughterhouse may not represent the bacterial status of the pig back in the herd......In the EU project SafeOrganic, the objective is to compare the level of antibiotic resistance in conventional pig herds with the level in organic pig herds, where a restricted use of antimicrobials is expected to result in less resistant bacteria. For such survey, sampling at the abattoir opposed......-colon in some pigs indicating a relatively short intestinal passage time after ingestion and then the risk of finding bacteria not originating from the host pig but from the environment. However, the proportion of the TET resistant E. coli in the large intestine appeared relatively stable over time, though...

  12. Clinical mastitis in Macedonian dairy herds

    Directory of Open Access Journals (Sweden)

    Trajčev M.

    2013-01-01

    Full Text Available The purpose of this study is the determination of the occurrence and prevalence of clinical mastitis and lactation incidence risk on three dairy farms. A one year study on a total of 1031 black-white breed cows with a total of 1267 lactations was performed. Each dairy farm implemented a different technology of rearing and was of different herd size (farm A - tie-stalls, 162 cows; farm B - loose-housing system with open shed and deep bedding, 357 dairy cows; and farm C - loosehousing system with enclosed shed, 512 cows. Clinical mastitis in cows was detected by clinical examination of the udder and determination of abnormalities in the milk. To distinguish two consecutive cases of clinical mastitis within the same lactation a time period of nine days was used. Annual prevalence rate of clinical mastitis for the entire population of cows was 34.13% on cow level, and 30.07% on lactation level. There was a high prevalence rate of clinical mastitis in primiparous cows, 21.43%, 40.77% and 12.55%, on farms A, B and C, respectively. Lactation incident risk for cows on farm A was 25.00%, farm B 95.58% and farm C 21.49%. The prevalence of clinical mastitis and lactation incidence risk tended to increase with increasing parity. The annual lactation risk for the entire population of cows was 45.86%. All indicators for the determination of the occurrence of clinical mastitis in dairy farms, which were observed during the research, showed the greatest values on farm B. Most of the cows manifested one (68.24% or two (18.63% cases of clinical mastitis during lactation. There was a long period in lactation until the appearance of the first case of clinical mastitis (112.21 ± 92.04 days. Generally, clinical mastitis was registered during the whole period of the survey, with some fluctuations between different seasons. The method of GLM (General Linear Model, univariate procedure, was used to analyze associations between the incidence of clinical mastitis and

  13. Hypopigmentation Induced by Frequent Low-Fluence, Large-Spot-Size QS Nd:YAG Laser Treatments.

    Science.gov (United States)

    Wong, Yisheng; Lee, Siong See Joyce; Goh, Chee Leok

    2015-12-01

    The Q-switched 1064-nm neodymium-doped yttrium aluminum garnet (QS 1064-nm Nd:YAG) laser is increasingly used for nonablative skin rejuvenation or "laser toning" for melasma. Multiple and frequent low-fluence, large-spot-size treatments are used to achieve laser toning, and these treatments are associated with the development of macular hypopigmentation as a complication. We present a case series of three patients who developed guttate hypomelanotic macules on the face after receiving laser toning treatment with QS 1064-nm Nd:YAG.

  14. Optimal Siting and Sizing of Energy Storage System for Power Systems with Large-scale Wind Power Integration

    DEFF Research Database (Denmark)

    Zhao, Haoran; Wu, Qiuwei; Huang, Shaojun

    2015-01-01

    This paper proposes algorithms for optimal sitingand sizing of Energy Storage System (ESS) for the operationplanning of power systems with large scale wind power integration.The ESS in this study aims to mitigate the wind powerfluctuations during the interval between two rolling Economic......Dispatches (EDs) in order to maintain generation-load balance.The charging and discharging of ESS is optimized consideringoperation cost of conventional generators, capital cost of ESSand transmission losses. The statistics from simulated systemoperations are then coupled to the planning process to determinethe...

  15. Can interface features affect aggression resulting from violent video game play? An examination of realistic controller and large screen size.

    Science.gov (United States)

    Kim, Ki Joon; Sundar, S Shyam

    2013-05-01

    Aggressiveness attributed to violent video game play is typically studied as a function of the content features of the game. However, can interface features of the game also affect aggression? Guided by the General Aggression Model (GAM), we examine the controller type (gun replica vs. mouse) and screen size (large vs. small) as key technological aspects that may affect the state aggression of gamers, with spatial presence and arousal as potential mediators. Results from a between-subjects experiment showed that a realistic controller and a large screen display induced greater aggression, presence, and arousal than a conventional mouse and a small screen display, respectively, and confirmed that trait aggression was a significant predictor of gamers' state aggression. Contrary to GAM, however, arousal showed no effects on aggression; instead, presence emerged as a significant mediator.

  16. Measurement of liquid mixing characteristics in large-sized ion exchange column for isotope separation by stepwise response method

    International Nuclear Information System (INIS)

    Fujine, Sachio; Saito, Keiichiro; Iwamoto, Kazumi; Itoi, Toshiaki.

    1981-07-01

    Liquid mixing in a large-sized ion exchange column for isotope separation was measured by the step-wise response method, using NaCl solution as tracer. A 50 cm diameter column was packed with an ion exchange resin of 200 μm in mean diameter. Experiments were carried out for several types of distributor and collector, which were attached to each end of the column. The smallest mixing was observed for the perforated plate type of the collector, coupled with a minimum stagnant volume above the ion exchange resin bed. The 50 cm diameter column exhibited the better characteristics of liquid mixing than the 2 cm diameter column for which the good performance of lithium isotope separation had already been confirmed. These results indicate that a large increment of throughput is attainable by the scale-up of column diameter with the same performance of isotope separation as for the 2 cm diameter column. (author)

  17. Large-size, high-uniformity, random silver nanowire networks as transparent electrodes for crystalline silicon wafer solar cells.

    Science.gov (United States)

    Xie, Shouyi; Ouyang, Zi; Jia, Baohua; Gu, Min

    2013-05-06

    Metal nanowire networks are emerging as next generation transparent electrodes for photovoltaic devices. We demonstrate the application of random silver nanowire networks as the top electrode on crystalline silicon wafer solar cells. The dependence of transmittance and sheet resistance on the surface coverage is measured. Superior optical and electrical properties are observed due to the large-size, highly-uniform nature of these networks. When applying the nanowire networks on the solar cells with an optimized two-step annealing process, we achieved as large as 19% enhancement on the energy conversion efficiency. The detailed analysis reveals that the enhancement is mainly caused by the improved electrical properties of the solar cells due to the silver nanowire networks. Our result reveals that this technology is a promising alternative transparent electrode technology for crystalline silicon wafer solar cells.

  18. Eco-friendly preparation of large-sized graphene via short-circuit discharge of lithium primary battery.

    Science.gov (United States)

    Kang, Shaohong; Yu, Tao; Liu, Tingting; Guan, Shiyou

    2018-02-15

    We proposed a large-sized graphene preparation method by short-circuit discharge of the lithium-graphite primary battery for the first time. LiC x is obtained through lithium ions intercalation into graphite cathode in the above primary battery. Graphene was acquired by chemical reaction between LiC x and stripper agents with dispersion under sonication conditions. The gained graphene is characterized by Raman spectrum, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Atomic force microscope (AFM) and Scanning electron microscopy (SEM). The results indicate that the as-prepared graphene has a large size and few defects, and it is monolayer or less than three layers. The quality of graphene is significant improved compared to the reported electrochemical methods. The yield of graphene can reach 8.76% when the ratio of the H 2 O and NMP is 3:7. This method provides a potential solution for the recycling of waste lithium ion batteries. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Prospects for the domestic production of large-sized cast blades and vanes for industrial gas turbines

    Science.gov (United States)

    Kazanskiy, D. A.; Grin, E. A.; Klimov, A. N.; Berestevich, A. I.

    2017-10-01

    Russian experience in the production of large-sized cast blades and vanes for industrial gas turbines is analyzed for the past decades. It is noted that the production of small- and medium-sized blades and vanes made of Russian alloys using technologies for aviation, marine, and gas-pumping turbines cannot be scaled for industrial gas turbines. It is shown that, in order to provide manufacturability under large-scale casting from domestic nickel alloys, it is necessary to solve complex problems in changing their chemical composition, to develop new casting technologies and to optimize the heat treatment modes. An experience of PAO NPO Saturn in manufacturing the blades and vanes made of ChS88U-VI and IN738-LC foundry nickel alloys for the turbines of the GTE-110 gas turbine unit is considered in detail. Potentialities for achieving adopted target parameters for the mechanical properties of working blades cast from ChS88UM-VI modified alloy are established. For the blades made of IN738-LC alloy manufactured using the existing foundry technology, a complete compliance with the requirements of normative and technical documentation has been established. Currently, in Russia, the basis of the fleet of gas turbine plants is composed by foreign turbines, and, for the implementation of the import substitution program, one can use the positive experience of PAO NPO Saturn in casting blades from IN738-LC alloy based on a reverse engineering technique. A preliminary complex of studies of the original manufacturer's blades should be carried out, involving, first of all, the determination of geometric size using modern measurement methods as well as the studies on the chemical compositions of the used materials (base metal and protective coatings). Further, verifying the constructed calculation models based on the obtained data, one could choose available domestic materials that would meet the operating conditions of the blades according to their heat resistance and corrosion

  20. Development of a composite large-size SiPM (assembled matrix) based modular detector cluster for MAGIC

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, A., E-mail: ahahn@mpp.mpg.de [Max Planck Institute for Physics (Werner-Heisenberg-Institut), Föhringer Ring 6, 80805 München (Germany); Mazin, D., E-mail: mazin@mpp.mpg.de [Max Planck Institute for Physics (Werner-Heisenberg-Institut), Föhringer Ring 6, 80805 München (Germany); Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwa-no-Ha, Kashiwa City, Chiba 277–8582 (Japan); Bangale, P., E-mail: priya@mpp.mpg.de [Max Planck Institute for Physics (Werner-Heisenberg-Institut), Föhringer Ring 6, 80805 München (Germany); Dettlaff, A., E-mail: todettl@mpp.mpg.de [Max Planck Institute for Physics (Werner-Heisenberg-Institut), Föhringer Ring 6, 80805 München (Germany); Fink, D., E-mail: fink@mpp.mpg.de [Max Planck Institute for Physics (Werner-Heisenberg-Institut), Föhringer Ring 6, 80805 München (Germany); Grundner, F., E-mail: grundner@mpp.mpg.de [Max Planck Institute for Physics (Werner-Heisenberg-Institut), Föhringer Ring 6, 80805 München (Germany); Haberer, W., E-mail: haberer@mpp.mpg.de [Max Planck Institute for Physics (Werner-Heisenberg-Institut), Föhringer Ring 6, 80805 München (Germany); Maier, R., E-mail: rma@mpp.mpg.de [Max Planck Institute for Physics (Werner-Heisenberg-Institut), Föhringer Ring 6, 80805 München (Germany); and others

    2017-02-11

    The MAGIC collaboration operates two 17 m diameter Imaging Atmospheric Cherenkov Telescopes (IACTs) on the Canary Island of La Palma. Each of the two telescopes is currently equipped with a photomultiplier tube (PMT) based imaging camera. Due to the advances in the development of Silicon Photomultipliers (SiPMs), they are becoming a widely used alternative to PMTs in many research fields including gamma-ray astronomy. Within the Otto-Hahn group at the Max Planck Institute for Physics, Munich, we are developing a SiPM based detector module for a possible upgrade of the MAGIC cameras and also for future experiments as, e.g., the Large Size Telescopes (LST) of the Cherenkov Telescope Array (CTA). Because of the small size of individual SiPM sensors (6 mm×6 mm) with respect to the 1-inch diameter PMTs currently used in MAGIC, we use a custom-made matrix of SiPMs to cover the same detection area. We developed an electronic circuit to actively sum up and amplify the SiPM signals. Existing non-imaging hexagonal light concentrators (Winston cones) used in MAGIC have been modified for the angular acceptance of the SiPMs by using C++ based ray tracing simulations. The first prototype based detector module includes seven channels and was installed into the MAGIC camera in May 2015. We present the results of the first prototype and its performance as well as the status of the project and discuss its challenges. - Highlights: • The design of the first SiPM large-size IACT pixel is described. • The simulation of the light concentrators is presented. • The temperature stability of the detector module is demonstrated. • The calibration procedure of SiPM device in the field is described.

  1. An Examination of Teachers' Perceptions and Practice when Teaching Large and Reduced-Size Classes: Do Teachers Really Teach Them in the Same Way?

    Science.gov (United States)

    Harfitt, Gary James

    2012-01-01

    Class size research suggests that teachers do not vary their teaching strategies when moving from large to smaller classes. This study draws on interviews and classroom observations of three experienced English language teachers working with large and reduced-size classes in Hong Kong secondary schools. Findings from the study point to subtle…

  2. Serological patterns of Actinobacillus pleuropneumoniae, Mycoplasma hyopneumoniae, Pasteurella multocida and Streptococcus suis in pig herds affected by pleuritis.

    Science.gov (United States)

    Wallgren, Per; Nörregård, Erik; Molander, Benedicta; Persson, Maria; Ehlorsson, Carl-Johan

    2016-10-04

    Respiratory illness is traditionally regarded as the disease of the growing pig, and has historically mainly been associated to bacterial infections with focus on Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae. These bacteria still are of great importance, but continuously increasing herd sizes have complicated the scenario and the influence of secondary invaders may have been increased. The aim of this study was to evaluate the presence of A. pleuropneumoniae and M. hyopneumoniae, as well as that of the secondary invaders Pasteurella multocida and Streptococcus suis by serology in four pig herds (A-D) using age segregated rearing systems with high incidences of pleuritic lesions at slaughter. Pleuritic lesions registered at slaughter ranged from 20.5 to 33.1 % in the four herds. In herd A, the levels of serum antibodies to A. pleuropneumoniae exceeded A 450  > 1.5, but not to any other microbe searched for. The seroconversion took place early during the fattening period. Similar levels of serum antibodies to A. pleuropneumoniae were also recorded in herd B, with a subsequent increase in levels of antibodies to P. multocida. Pigs seroconverted to both agents during the early phase of the fattening period. In herd C, pigs seroconverted to P. multocida during the early phase of the fattening period and thereafter to A. pleuropneumoniae. In herd D, the levels of antibodies to P. multocida exceeded A 450  > 1.0 in absence (A 450  hyopneumoniae and to S. suis remained below A 450  hyopneumoniae late during the rearing period (herd B-D), or not at all (herd A). Different serological patterns were found in the four herds with high levels of serum antibodies to A. pleuropneumoniae and P. multocida, either alone or in combination with each other. Seroconversion to M. hyopneumoniae late during the rearing period or not at all, confirmed the positive effect of age segregated rearing in preventing or delaying infections with M

  3. Runne-Beana: Dog Herds Ethnographer

    Directory of Open Access Journals (Sweden)

    Myrdene Anderson

    2016-12-01

    Full Text Available Saami society in Lapland (now often called Saapmi, particularly the seasonally-nomadic reindeer-breeding sector, is predicated upon mobility and autonomy of its actors. Runne-Beana, a talented reindeer-herding dog, exhibited both mobility and autonomy when allocating to himself a peripatetic ethnographer, on the first day of five years of doctoral dissertation fieldwork in arctic Norway in 1972. That family’s and the wider community’s reactions to Runne-Beana’s behavior, and mine, highlight the tensions when mobility and autonomy compound with ideologies of ownership and control. At the same time, his companionship profoundly shaped all field relationships, engendering an understanding of dog culture as it is manifest in the herder/herding dog/reindeer triad and in the interpenetration of assumptions concerning child/dog enculturation.

  4. Dynamic production monitoring in pig herds II

    DEFF Research Database (Denmark)

    Bono, Claudia; Cornou, Cecile; Lundbye-Christensen, Søren

    2013-01-01

    an expectation-maximization (EM) algorithm applied on a dataset containing data from 15 herds, each of them including insemination and farrowing observations over a period ranging from 150 to 800 weeks. The model included a set of parameters describing the parity-specific farrowing rate and the re......-insemination effect. It also provided reliable forecasting on weekly basis. Statistical control tools were used to give warnings in case of impaired farrowing rate. For each herd, farrowing rate profile, analysis of model components over time and detection of alarms were computed. The model provided a good overview...... of the development of the parity specific farrowing rate over time and the control charts were able to detect impaired results. Suggestions for future improvements include addition of parity-specific control charts, calibration of the charts for use in practice and inclusion of a sow effect in the farrowing model....

  5. Epidemiological situation of Herpesvirus infections in buffalo herds: Bubaline Herpesvirus1 or Bovine Herpesvirus1?

    Directory of Open Access Journals (Sweden)

    G.L. Autorino

    2010-02-01

    Full Text Available Information on the distribution and related epidemiological characteristics of herpesvirus infections, and in particular referring to Bovine Herpesvirus 1 (BoHV1 and Bubaline Herpesvirus 1 (BuHV1 in buffaloes, have to date not been reported. Different studies based on serological surveys and viral isolation describe the circulation of both infections in this species. The specific etiological attribution of the infections in sero-surveys can be uncertain because of antigenic cross-reactivity of these ruminant α-herpesvirus and therefore depends on the diagnostic techniques employed. For this , we proceeded in verifying the diffusion of the two infections in a buffalo population of Central Italy. The sample size for the number of herds to test was defined considering an expected prevalence > 20% and the number of heads to be tested within each herd was established using an expected prevalence of > 25% (absolute precision of 5%, with 95% confidence level. The 155 herds to test were those with no IBR vaccination history. A maximum of 15 random blood samples were collected within the >3 year age category. The same sampling criteria was adopted when cows were present on buffalo farms to study the possible role of this species. Through the combined use of gB-gE Elisa tests, we assigned a specific infection status, for the BuHV1 infection status (gB-pos/gE-neg, as confirmed by an experimental infection conducted by us inoculating buffaloes with the BuHV1 “strain Metzler”, and for the BoHV1 status (gBpos/ gE-pos as that observed for the infection in bovines. Prevalence of infection, based on the Elisa status of each animal, were estimated for the whole sample and within each herd. Furthermore, the selected farms were investigated for their numeric consistency, presence of bovines, occurrence of typical clinical herpesvirus disorders occurring during the year prior to sampling. The association of these factors with the infection status was verified

  6. Herd-level risk factors for bovine tuberculosis in French cattle herds.

    Science.gov (United States)

    Marsot, Maud; Béral, Marina; Scoizec, Axelle; Mathevon, Yoann; Durand, Benoit; Courcoul, Aurélie

    2016-09-01

    Although officially free of bovine tuberculosis (bTB), France has been experiencing a slight increase in the incidence and geographical spread of the infection. Eradication of bTB requires determining the infection risk factors. Although several studies identifying bTB risk factors have been conducted in the United Kingdom and Spain, no information is currently available regarding bTB risk factors in French cattle. The objective of this work was thus to study the factors associated with the risk of bTB in cattle herds in three French administrative divisions (départements of Ardennes, Côte d'Or and Dordogne). A case-control study was conducted to compare herds having experienced a bTB outbreak between 2012 and early 2014 with randomly selected control herds of the three study départements. A questionnaire of farming practices, inter-herd contacts (e.g. at pasture or via vehicles or materials), and the presence of other domestic species was carried out in the selected herds. Data on other variables of interest included animal movements between farms and potential contacts between cattle and wildlife (e.g. badger and wild boar abundances) were also collected. Multivariable logistic regression and multimodel inference methods were used to assess risk factors related to bTB. A total of 216 herds (72 cases and 144 controls) were analyzed. The two main risk factors were the presence of a recent neighboring outbreak, being defined as a neighboring herd at pasture reported as infected in the past two years (odds ratio (OR)=3.6; population attributable fraction (PAF)=30.7%) and the presence of a farm building for cattle housing or for feed storage located at more than 300-m from inhabited areas (OR=2.3; PAF=27.6%). Another risk factor was related to sharing water points at pasture with a recent neighboring outbreak. Results illustrated the multifactorial nature of bTB dynamics. The risk factors related to recently infected neighboring herds could be attributable to

  7. From mantle to critical zone: A review of large and giant sized deposits of the rare earth elements

    Directory of Open Access Journals (Sweden)

    M.P. Smith

    2016-05-01

    Full Text Available The rare earth elements are unusual when defining giant-sized ore deposits, as resources are often quoted as total rare earth oxide, but the importance of a deposit may be related to the grade for individual, or a limited group of the elements. Taking the total REE resource, only one currently known deposit (Bayan Obo would class as giant (>1.7 × 107 tonnes contained metal, but a range of others classify as large (>1.7 × 106 tonnes. With the exception of unclassified resource estimates from the Olympic Dam IOCG deposit, all of these deposits are related to alkaline igneous activity – either carbonatites or agpaitic nepheline syenites. The total resource in these deposits must relate to the scale of the primary igneous source, but the grade is a complex function of igneous source, magmatic crystallisation, hydrothermal modification and supergene enrichment during weathering. Isotopic data suggest that the sources conducive to the formation of large REE deposits are developed in subcontinental lithospheric mantle, enriched in trace elements either by plume activity, or by previous subduction. The reactivation of such enriched mantle domains in relatively restricted geographical areas may have played a role in the formation of some of the largest deposits (e.g. Bayan Obo. Hydrothermal activity involving fluids from magmatic to meteoric sources may result in the redistribution of the REE and increases in grade, depending on primary mineralogy and the availability of ligands. Weathering and supergene enrichment of carbonatite has played a role in the formation of the highest grade deposits at Mount Weld (Australia and Tomtor (Russia. For the individual REE with the current highest economic value (Nd and the HREE, the boundaries for the large and giant size classes are two orders of magnitude lower, and deposits enriched in these metals (agpaitic systems, ion absorption deposits may have significant economic impact in the near future.

  8. THE INFRARED SPECTRA OF VERY LARGE IRREGULAR POLYCYCLIC AROMATIC HYDROCARBONS (PAHs): OBSERVATIONAL PROBES OF ASTRONOMICAL PAH GEOMETRY, SIZE, AND CHARGE

    International Nuclear Information System (INIS)

    Bauschlicher, Charles W.; Peeters, Els; Allamandola, Louis J.

    2009-01-01

    The mid-infrared (IR) spectra of six large, irregular polycyclic aromatic hydrocarbons (PAHs) with formulae (C 84 H 24 -C 120 H 36 ) have been computed using density functional theory (DFT). Trends in the dominant band positions and intensities are compared to those of large, compact PAHs as a function of geometry, size, and charge. Irregular edge moieties that are common in terrestrial PAHs, such as bay regions and rings with quartet hydrogens, are shown to be uncommon in astronomical PAHs. As for all PAHs comprised solely of C and H reported to date, mid-IR emission from irregular PAHs fails to produce a strong CC str band at 6.2 μm, the position characteristic of the important, class A astronomical PAH spectra. Earlier studies showed that inclusion of nitrogen within a PAH shifts this to 6.2 μm for PAH cations. Here we show that this band shifts to 6.3 μm in nitrogenated PAH anions, close to the position of the CC stretch in class B astronomical PAH spectra. Thus, nitrogenated PAHs may be important in all sources and the peak position of the CC stretch near 6.2 μm appears to directly reflect the PAH cation to anion ratio. Large irregular PAHs exhibit features at 7.8 μm but lack them near 8.6 μm. Hence, the 7.7 μm astronomical feature is produced by a mixture of small and large PAHs while the 8.6 μm band can only be produced by large compact PAHs. As with the CC str , the position and profile of these bands reflect the PAH cation to anion ratio.

  9. Scaling of the Urban Water Footprint: An Analysis of 65 Mid- to Large-Sized U.S. Metropolitan Areas

    Science.gov (United States)

    Mahjabin, T.; Garcia, S.; Grady, C.; Mejia, A.

    2017-12-01

    Scaling laws have been shown to be relevant to a range of disciplines including biology, ecology, hydrology, and physics, among others. Recently, scaling was shown to be important for understanding and characterizing cities. For instance, it was found that urban infrastructure (water supply pipes and electrical wires) tends to scale sublinearly with city population, implying that large cities are more efficient. In this study, we explore the scaling of the water footprint of cities. The water footprint is a measure of water appropriation that considers both the direct and indirect (virtual) water use of a consumer or producer. Here we compute the water footprint of 65 mid- to large-sized U.S. metropolitan areas, accounting for direct and indirect water uses associated with agricultural and industrial commodities, and residential and commercial water uses. We find that the urban water footprint, computed as the sum of the water footprint of consumption and production, exhibits sublinear scaling with an exponent of 0.89. This suggests the possibility of large cities being more water-efficient than small ones. To further assess this result, we conduct additional analysis by accounting for international flows, and the effects of green water and city boundary definition on the scaling. The analysis confirms the scaling and provides additional insight about its interpretation.

  10. Influence of age, sex and herd characteristics on the occurrence of verocytotoxin-producing Escherichia coli O157 in Danish dairy farms

    DEFF Research Database (Denmark)

    Nielsen, E.M.; Tegtmeier, Conny; Andersen, Hans Jørgen

    2002-01-01

    animals were sampled, and 3.6% of these excreted VTEC O157. These animals were located on 10 farms (17%). On average, 21% of the sampled animals in the positive herds excreted VTEC O157. Register data, including age, sex, breed, housing conditions and herd composition, were extracted from a database....... No influence of herd size or housing conditions was found. A strong effect of age was seen with 2-6-month-old calves as the high-risk age group (8.6% positive) in contrast to calves...

  11. Theoretical simulation and analysis of large size BMP-LSC by 3D Monte Carlo ray tracing model

    International Nuclear Information System (INIS)

    Zhang Feng; Zhang Ning-Ning; Yan Sen; Song Sun; Jun Bao; Chen Gao; Zhang Yi

    2017-01-01

    Luminescent solar concentrators (LSC) can reduce the area of solar cells by collecting light from a large area and concentrating the captured light onto relatively small area photovoltaic (PV) cells, and thereby reducing the cost of PV electricity generation. LSCs with bottom-facing cells (BMP-LSC) can collect both direct light and indirect light, so further improving the efficiency of the PV cells. However, it is hard to analyze the effect of each parameter by experiment because there are too many parameters involved in the BMP-LSC. In this paper, all the physical processes of the light transmission and collection in the BMP-LSC were analyzed. A three-dimensional Monte Carlo ray tracing program was developed to study the transmission of photons in the LSC. A larger-size LSC was simulated, and the effects of dye concentration, the LSC thickness, the cell area, and the cell distance were systematically analyzed. (paper)

  12. Phylogenetic relationships of hexaploid large-sized barbs (genus Labeobarbus, Cyprinidae) based on mtDNA data.

    Science.gov (United States)

    Tsigenopoulos, Costas S; Kasapidis, Panagiotis; Berrebi, Patrick

    2010-08-01

    The phylogenetic relationships among species of the Labeobarbus genus (Teleostei, Cyprinidae) which comprises large body-sized hexaploid taxa were inferred using complete cytochrome b mitochondrial gene sequences. Molecular data suggest two main evolutionary groups which roughly correspond to a Northern (Middle East and Northwest Africa) and a sub-Saharan lineage. The splitting of the African hexaploids from their Asian ancestors and their subsequent diversification on the African continent occurred in the Late Miocene, a period in which other cyprinins also invaded Africa and radiated in the Mediterranean region. Finally, systematic implications of these results to the taxonomic validity of genera or subgenera such as Varicorhinus, Kosswigobarbus, Carasobarbus and Capoeta are further discussed. Copyright 2010 Elsevier Inc. All rights reserved.

  13. How do low dispersal species establish large range sizes? The case of the water beetle Graphoderus bilineatus

    DEFF Research Database (Denmark)

    Iversen, Lars Lønsmann; Rannap, Riinu; Thomsen, Philip Francis

    2013-01-01

    important than species phylogeny or local spatial attributes. In this study we used the water beetle Graphoderus bilineatus a philopatric species of conservation concern in Europe as a model to explain large range size and to support effective conservation measures for such species that also have limited...... systems and wetlands which used to be highly connected throughout the central plains of Europe. Our data suggest that a broad habitat niche can prevent landscape elements from becoming barriers for species like G. bilineatus. Therefore, we question the usefulness of site protection as conservation...... measures for G. bilineatus and similar philopatric species. Instead, conservation actions should be focused at the landscape level to ensure a long-term viability of such species across their range....

  14. Chemical and electrochemical synthesis of nano-sized TiO{sub 2} anatase for large-area photon conversion

    Energy Technology Data Exchange (ETDEWEB)

    Babasaheb, Raghunath Sankapal; Shrikrishna, Dattatraya Sartale; Lux-Steiner, M.Ch.; Ennaoui, A. [Hahn-Meitner-Institut, Div. of Solar Energy Research, Berlin (Germany)

    2006-05-15

    We report on the synthesis of nanocrystalline titanium dioxide thin films and powders by chemical and electrochemical deposition methods. Both methods are simple, inexpensive and suitable for large-scale production. Air-annealing of the films and powders at T = 500 C leads to densely packed nanometer sized anatase TiO{sub 2} particles. The obtained layers are characterized by different methods such as: X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Titanium dioxide TiO{sub 2} (anatase) phase with (101) preferred orientation has been obtained for the films deposited on glass; indium doped tin oxide (ITO) and quartz substrates. The powder obtained as the byproduct consists of TiO{sub 2} with anatase-phase as well. (authors)

  15. Chemical and electrochemical synthesis of nano-sized TiO2 anatase for large-area photon conversion

    International Nuclear Information System (INIS)

    Babasaheb, Raghunath Sankapal; Shrikrishna, Dattatraya Sartale; Lux-Steiner, M.Ch.; Ennaoui, A.

    2006-01-01

    We report on the synthesis of nanocrystalline titanium dioxide thin films and powders by chemical and electrochemical deposition methods. Both methods are simple, inexpensive and suitable for large-scale production. Air-annealing of the films and powders at T = 500 C leads to densely packed nanometer sized anatase TiO 2 particles. The obtained layers are characterized by different methods such as: X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Titanium dioxide TiO 2 (anatase) phase with (101) preferred orientation has been obtained for the films deposited on glass; indium doped tin oxide (ITO) and quartz substrates. The powder obtained as the byproduct consists of TiO 2 with anatase-phase as well. (authors)

  16. Growth of large size lithium niobate single crystals of high quality by tilting-mirror-type floating zone method

    Energy Technology Data Exchange (ETDEWEB)

    Sarker, Abdur Razzaque, E-mail: razzaque_ru2000@yahoo.com [Department of Physics, University of Rajshahi (Bangladesh)

    2016-05-15

    Large size high quality LiNbO{sub 3} single crystals were grown successfully by tilting-mirror-type floating zone (TMFZ) technique. The grown crystals were characterized by X-ray diffraction, etch pits density measurement, Impedance analysis, Vibrating sample magnetometry (VSM) and UV-Visible spectrometry. The effect of mirror tilting during growth on the structural, electrical, optical properties and defect density of the LiNbO{sub 3} crystals were investigated. It was found that the defect density in the crystals reduced for tilting the mirror in the TMFZ method. The chemical analysis revealed that the grown crystals were of high quality with uniform composition. The single crystals grown by TMFZ method contains no low-angle grain boundaries, indicating that they can be used for high efficiency optoelectronic devices. (author)

  17. Synthesis of a large-sized mesoporous phosphosilicate thin film through evaporation-induced polymeric micelle assembly.

    Science.gov (United States)

    Li, Yunqi; Bastakoti, Bishnu Prasad; Imura, Masataka; Suzuki, Norihiro; Jiang, Xiangfen; Ohki, Shinobu; Deguchi, Kenzo; Suzuki, Madoka; Arai, Satoshi; Yamauchi, Yusuke

    2015-01-01

    A triblock copolymer, poly(styrene-b-2-vinyl pyridine-b-ethylene oxide) (PS-b-P2VP-b-PEO) was used as a soft template to synthesize large-sized mesoporous phosphosilicate thin films. The kinetically frozen PS core stabilizes the micelles. The strong interaction of the inorganic precursors with the P2VP shell enables the fabrication of highly robust walls of phosphosilicate and the PEO helps orderly packing of the micelles during solvent evaporation. The molar ratio of phosphoric acid and tetraethyl orthosilicate is crucial to achieve the final mesostructure. The insertion of phosphorus species into the siloxane network is studied by (29) Si and (31) P MAS NMR spectra. The mesoporous phosphosilicate films exhibit steady cell adhesion properties and show great promise as excellent materials in bone-growth engineering applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Easy and General Synthesis of Large-Sized Mesoporous Rare-Earth Oxide Thin Films by 'Micelle Assembly'.

    Science.gov (United States)

    Li, Yunqi; Bastakoti, Bishnu Prasad; Imura, Masataka; Dai, Pengcheng; Yamauchi, Yusuke

    2015-12-01

    Large-sized (ca. 40 nm) mesoporous Er2O3 thin films are synthesized by using a triblock copolymer poly(styrene-b-2-vinyl pyridine-b-ethylene oxide) (PS-b-P2VP-b-PEO) as a pore directing agent. Each block makes different contributions and the molar ratio of PVP/Er(3+) is crucial to guide the resultant mesoporous structure. An easy and general method is proposed and used to prepare a series of mesoporous rare-earth oxide (Sm2O3, Dy2O3, Tb2O3, Ho2O3, Yb2O3, and Lu2O3) thin films with potential uses in electronics and optical devices. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Epidemiology and impact of Fasciola hepatica exposure in high-yielding dairy herds.

    Science.gov (United States)

    Howell, Alison; Baylis, Matthew; Smith, Rob; Pinchbeck, Gina; Williams, Diana

    2015-09-01

    The liver fluke Fasciola hepatica is a trematode parasite with a worldwide distribution and is the cause of important production losses in the dairy industry. The aim of this observational study was to assess the prevalence of exposure to F. hepatica in a group of high yielding dairy herds, to determine the risk factors and investigate their associations with production and fertility parameters. Bulk milk tank samples from 606 herds that supply a single retailer with liquid milk were tested with an antibody ELISA for F. hepatica. Multivariable linear regression was used to investigate the effect of farm management and environmental risk factors on F. hepatica exposure. Higher rainfall, grazing boggy pasture, presence of beef cattle on farm, access to a stream or pond and smaller herd size were associated with an increased risk of exposure. Univariable regression was used to look for associations between fluke exposure and production-related variables including milk yield, composition, somatic cell count and calving index. Although causation cannot be assumed, a significant (phepatica exposure and estimated milk yield at the herd level, representing a 15% decrease in yield for an increase in F. hepatica exposure from the 25th to the 75th percentile. This remained significant when fertility, farm management and environmental factors were controlled for. No associations were found between F. hepatica exposure and any of the other production, disease or fertility variables. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  20. A global optimization algorithm inspired in the behavior of selfish herds.

    Science.gov (United States)

    Fausto, Fernando; Cuevas, Erik; Valdivia, Arturo; González, Adrián

    2017-10-01

    In this paper, a novel swarm optimization algorithm called the Selfish Herd Optimizer (SHO) is proposed for solving global optimization problems. SHO is based on the simulation of the widely observed selfish herd behavior manifested by individuals within a herd of animals subjected to some form of predation risk. In SHO, individuals emulate the predatory interactions between groups of prey and predators by two types of search agents: the members of a selfish herd (the prey) and a pack of hungry predators. Depending on their classification as either a prey or a predator, each individual is conducted by a set of unique evolutionary operators inspired by such prey-predator relationship. These unique traits allow SHO to improve the balance between exploration and exploitation without altering the population size. To illustrate the proficiency and robustness of the proposed method, it is compared to other well-known evolutionary optimization approaches such as Particle Swarm Optimization (PSO), Artificial Bee Colony (ABC), Firefly Algorithm (FA), Differential Evolution (DE), Genetic Algorithms (GA), Crow Search Algorithm (CSA), Dragonfly Algorithm (DA), Moth-flame Optimization Algorithm (MOA) and Sine Cosine Algorithm (SCA). The comparison examines several standard benchmark functions, commonly considered within the literature of evolutionary algorithms. The experimental results show the remarkable performance of our proposed approach against those of the other compared methods, and as such SHO is proven to be an excellent alternative to solve global optimization problems. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Contextual herd factors associated with cow culling risk in Québec dairy herds: A multilevel analysis.

    Science.gov (United States)

    Haine, Denis; Delgado, Hector; Cue, Roger; Sewalem, Asheber; Wade, Kevin; Lacroix, René; Lefebvre, Daniel; Arsenault, Julie; Bouchard, Émile; Dubuc, Jocelyn

    2017-09-01

    Several health disorders, such as milk fever, displaced abomasum, and mastitis, as well as impaired reproductive performance, are known risk factors for the removal of affected cows from a dairy herd. While cow-level risk factors are well documented in the literature, herd-level associations have been less frequently investigated. The objective of this study was to investigate the effect of cow- and herd-level determinants on variations in culling risk in Québec dairy herds: whether herd influences a cow's culling risk. For this, we assessed the influence of herd membership on cow culling risk according to displaced abomasum, milk fever, and retained placenta. A retrospective longitudinal study was conducted on data from dairy herds in the Province of Québec, Canada, by extracting health information events from the dairy herd health management software used by most Québec dairy producers and their veterinarians. Data were extracted for all lactations starting between January 1st and December 31st, 2010. Using multilevel logistic regression, we analysed a total of 10,529 cows from 201 herds that met the inclusion criteria. Milk fever and displaced abomasum were demonstrated to increase the cow culling risk. A minor general herd effect was found for the culling risk (i.e. an intra-class correlation of 1.0% and median odds ratio [MOR] of 1.20). The proportion of first lactation cows was responsible for this significant, but weak herd effect on individual cow culling risk, after taking into account the cow-level factors. On the other hand, the herd's average milk production was a protective factor. The planning and management of forthcoming replacement animals has to be taken into consideration when assessing cow culling risks and herd culling rates. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Long-term resource variation and group size: A large-sample field test of the Resource Dispersion Hypothesis

    Directory of Open Access Journals (Sweden)

    Morecroft Michael D

    2001-07-01

    Full Text Available Abstract Background The Resource Dispersion Hypothesis (RDH proposes a mechanism for the passive formation of social groups where resources are dispersed, even in the absence of any benefits of group living per se. Despite supportive modelling, it lacks empirical testing. The RDH predicts that, rather than Territory Size (TS increasing monotonically with Group Size (GS to account for increasing metabolic needs, TS is constrained by the dispersion of resource patches, whereas GS is independently limited by their richness. We conducted multiple-year tests of these predictions using data from the long-term study of badgers Meles meles in Wytham Woods, England. The study has long failed to identify direct benefits from group living and, consequently, alternative explanations for their large group sizes have been sought. Results TS was not consistently related to resource dispersion, nor was GS consistently related to resource richness. Results differed according to data groupings and whether territories were mapped using minimum convex polygons or traditional methods. Habitats differed significantly in resource availability, but there was also evidence that food resources may be spatially aggregated within habitat types as well as between them. Conclusions This is, we believe, the largest ever test of the RDH and builds on the long-term project that initiated part of the thinking behind the hypothesis. Support for predictions were mixed and depended on year and the method used to map territory borders. We suggest that within-habitat patchiness, as well as model assumptions, should be further investigated for improved tests of the RDH in the future.

  3. The potential of natural gas use including cogeneration in large-sized industry and commercial sector in Peru

    International Nuclear Information System (INIS)

    Gonzales Palomino, Raul; Nebra, Silvia A.

    2012-01-01

    In recent years there have been several discussions on a greater use of natural gas nationwide. Moreover, there have been several announcements by the private and public sectors regarding the construction of new pipelines to supply natural gas to the Peruvian southern and central-north markets. This paper presents future scenarios for the use of natural gas in the large-sized industrial and commercial sectors of the country based on different hypotheses on developments in the natural gas industry, national economic growth, energy prices, technological changes and investment decisions. First, the paper estimates the market potential and characterizes the energy consumption. Then it makes a selection of technological alternatives for the use of natural gas, and it makes an energetic and economic analysis and economic feasibility. Finally, the potential use of natural gas is calculated through nine different scenarios. The natural gas use in cogeneration systems is presented as an alternative to contribute to the installed power capacity of the country. Considering the introduction of the cogeneration in the optimistic–advanced scenario and assuming that all of their conditions would be put into practice, in 2020, the share of the cogeneration in electricity production in Peru would be 9.9%. - Highlights: ► This paper presents future scenarios for the use of natural gas in the large-sized industrial and commercial sectors of Peru. ► The potential use of natural gas is calculated through nine different scenarios.► The scenarios were based on different hypotheses on developments in the natural gas industry, national economic growth, energy prices, technological changes and investment decisions. ► We estimated the market potential and characterized the energy consumption, and made a selection of technological alternatives for the use of natural gas.

  4. FR-type radio sources in COSMOS: relation of radio structure to size, accretion modes and large-scale environment

    Science.gov (United States)

    Vardoulaki, Eleni; Faustino Jimenez Andrade, Eric; Delvecchio, Ivan; Karim, Alexander; Smolčić, Vernesa; Magnelli, Benjamin; Bertoldi, Frank; Schinnener, Eva; Sargent, Mark; Finoguenov, Alexis; VLA COSMOS Team

    2018-01-01

    The radio sources associated with active galactic nuclei (AGN) can exhibit a variety of radio structures, from simple to more complex, giving rise to a variety of classification schemes. The question which still remains open, given deeper surveys revealing new populations of radio sources, is whether this plethora of radio structures can be attributed to the physical properties of the host or to the environment. Here we present an analysis on the radio structure of radio-selected AGN from the VLA-COSMOS Large Project at 3 GHz (JVLA-COSMOS; Smolčić et al.) in relation to: 1) their linear projected size, 2) the Eddington ratio, and 3) the environment their hosts lie within. We classify these as FRI (jet-like) and FRII (lobe-like) based on the FR-type classification scheme, and compare them to a sample of jet-less radio AGN in JVLA-COSMOS. We measure their linear projected sizes using a semi-automatic machine learning technique. Their Eddington ratios are calculated from X-ray data available for COSMOS. As environmental probes we take the X-ray groups (hundreds kpc) and the density fields (~Mpc-scale) in COSMOS. We find that FRII radio sources are on average larger than FRIs, which agrees with literature. But contrary to past studies, we find no dichotomy in FR objects in JVLA-COSMOS given their Eddington ratios, as on average they exhibit similar values. Furthermore our results show that the large-scale environment does not explain the observed dichotomy in lobe- and jet-like FR-type objects as both types are found on similar environments, but it does affect the shape of the radio structure introducing bents for objects closer to the centre of an X-ray group.

  5. Development of a composite large-size SiPM (assembled matrix) based modular detector cluster for MAGIC

    Science.gov (United States)

    Hahn, A.; Mazin, D.; Bangale, P.; Dettlaff, A.; Fink, D.; Grundner, F.; Haberer, W.; Maier, R.; Mirzoyan, R.; Podkladkin, S.; Teshima, M.; Wetteskind, H.

    2017-02-01

    The MAGIC collaboration operates two 17 m diameter Imaging Atmospheric Cherenkov Telescopes (IACTs) on the Canary Island of La Palma. Each of the two telescopes is currently equipped with a photomultiplier tube (PMT) based imaging camera. Due to the advances in the development of Silicon Photomultipliers (SiPMs), they are becoming a widely used alternative to PMTs in many research fields including gamma-ray astronomy. Within the Otto-Hahn group at the Max Planck Institute for Physics, Munich, we are developing a SiPM based detector module for a possible upgrade of the MAGIC cameras and also for future experiments as, e.g., the Large Size Telescopes (LST) of the Cherenkov Telescope Array (CTA). Because of the small size of individual SiPM sensors (6 mm×6 mm) with respect to the 1-inch diameter PMTs currently used in MAGIC, we use a custom-made matrix of SiPMs to cover the same detection area. We developed an electronic circuit to actively sum up and amplify the SiPM signals. Existing non-imaging hexagonal light concentrators (Winston cones) used in MAGIC have been modified for the angular acceptance of the SiPMs by using C++ based ray tracing simulations. The first prototype based detector module includes seven channels and was installed into the MAGIC camera in May 2015. We present the results of the first prototype and its performance as well as the status of the project and discuss its challenges.

  6. Dairy herd mastitis and reproduction: using simulation to aid interpretation of results from discrete time survival analysis.

    Science.gov (United States)

    Hudson, Christopher D; Bradley, Andrew J; Breen, James E; Green, Martin J

    2015-04-01

    Probabilistic sensitivity analysis (PSA) is a simulation-based technique for evaluating the relative importance of different inputs to a complex process model. It is commonly employed in decision analysis and for evaluation of the potential impact of uncertainty in research findings on clinical practice, but has a wide variety of other possible applications. In this example, it was used to evaluate the association between herd-level udder health and reproductive performance in dairy herds. Although several recent studies have found relatively large associations between mastitis and fertility at the level of individual inseminations or lactations, the current study demonstrated that herd-level intramammary infection status is highly unlikely to have a clinically significant impact on the overall reproductive performance of a dairy herd under typical conditions. For example, a large increase in incidence rate of clinical mastitis (from 92 to 131 cases per 100 cows per year) would be expected to increase a herd's modified FERTEX score (a cost-based measure of overall reproductive performance) by just £4.50(1) per cow per year. The herd's background level of submission rate (proportion of eligible cows served every 21 days) and pregnancy risk (proportion of inseminations leading to a pregnancy) correlated strongly with overall reproductive performance and explained a large proportion of the between-herd variation in performance. PSA proved to be a highly useful technique to aid understanding of results from a complex statistical model, and has great potential for a wide variety of applications within the field of veterinary science. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Post-weaning multisystemic wasting syndrome (PMWS) in Danish pig herds: productivity, clinical symptoms, and pathology

    DEFF Research Database (Denmark)

    Nielsen, E. Okholm; Enøe, Claes; Jorsal, Sven Erik Lind

    2008-01-01

    were 36 g and 52 g less in the case herds than in the control herds. By examining three weaner pigs from each herd the PMWS diagnosis was confirmed by histopathology and immunohistochemistry in 78 per cent of the case herds, but at least one PMWS-positive weaner pig was found in 19 of the control herds...

  8. Postweaning multisystematic wasting syndrome in Danish pig herds: productivity, clinical signs and pathology

    DEFF Research Database (Denmark)

    Okholm Nielsen, Elisabeth; Enøe, Claes; Jorsal, Sven Erik Lind

    2008-01-01

    were 36 g and 52 g less in the case herds than in the control herds. By examining three weaner pigs from each herd the PMWS diagnosis was confirmed by histopathology and immunohistochemistry in 78 per cent of the case herds, but at least one PMWS-positive weaner pig was found in 19 of the control herds...

  9. Out-coupling membrane for large-size organic light-emitting panels with high efficiency and improved uniformity

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Lei, E-mail: dinglei@sust.edu.cn [College of Electrical and Information Engineering, Shaanxi University of Science and Technology, Xi’an, Shaanxi 710021 (China); Wang, Lu-Wei [College of Electrical and Information Engineering, Shaanxi University of Science and Technology, Xi’an, Shaanxi 710021 (China); Zhou, Lei, E-mail: zhzhlei@gmail.com [Faculty of Mathematics and Physics, Huaiyin Institute of Technology, Huai' an 223003 (China); Zhang, Fang-hui [College of Electrical and Information Engineering, Shaanxi University of Science and Technology, Xi’an, Shaanxi 710021 (China)

    2016-12-15

    Highlights: • An out-coupling membrane embedded with a scattering film of SiO{sub 2} spheres and polyethylene terephthalate (PET) plastic was successfully developed for 150 × 150 mm{sup 2} OLEDs. • Remarkable enhancement in efficiency was achieved from the OLEDs with out- coupling membrane. • The uniformity of large-size GOLED lighting panel is remarkably improved. - Abstract: An out-coupling membrane embedded with a scattering film of SiO{sub 2} spheres and polyethylene terephthalate (PET) plastic was successfully developed for 150 × 150 mm{sup 2} green OLEDs. Comparing with a reference OLED panel, an approximately 1-fold enhancement in the forward emission was obtained with an out-coupling membrane adhered to the surface of the external glass substrate of the panel. Moreover, it was verified that the emission color at different viewing angles can be stabilized without apparent spectral distortion. Particularly, the uniformity of the large-area OLEDs was greatly improved. Theoretical calculation clarified that the improved performance of the lighting panels is primarily attributed to the effect of particle scattering.

  10. Facile synthesis of uniform large-sized InP nanocrystal quantum dots using tris(tert-butyldimethylsilyl)phosphine

    Science.gov (United States)

    2012-01-01

    Colloidal III-V semiconductor nanocrystal quantum dots [NQDs] have attracted interest because they have reduced toxicity compared with II-VI compounds. However, the study and application of III-V semiconductor nanocrystals are limited by difficulties in their synthesis. In particular, it is difficult to control nucleation because the molecular bonds in III-V semiconductors are highly covalent. A synthetic approach of InP NQDs was presented using newly synthesized organometallic phosphorus [P] precursors with different functional moieties while preserving the P-Si bond. Introducing bulky side chains in our study improved the stability while facilitating InP formation with strong confinement at a readily low temperature regime (210°C to 300°C). Further shell coating with ZnS resulted in highly luminescent core-shell materials. The design and synthesis of P precursors for high-quality InP NQDs were conducted for the first time, and we were able to control the nucleation by varying the reactivity of P precursors, therefore achieving uniform large-sized InP NQDs. This opens the way for the large-scale production of high-quality Cd-free nanocrystal quantum dots. PMID:22289352

  11. Statistical process control charts for attribute data involving very large sample sizes: a review of problems and solutions.

    Science.gov (United States)

    Mohammed, Mohammed A; Panesar, Jagdeep S; Laney, David B; Wilson, Richard

    2013-04-01

    The use of statistical process control (SPC) charts in healthcare is increasing. The primary purpose of SPC is to distinguish between common-cause variation which is attributable to the underlying process, and special-cause variation which is extrinsic to the underlying process. This is important because improvement under common-cause variation requires action on the process, whereas special-cause variation merits an investigation to first find the cause. Nonetheless, when dealing with attribute or count data (eg, number of emergency admissions) involving very large sample sizes, traditional SPC charts often produce tight control limits with most of the data points appearing outside the control limits. This can give a false impression of common and special-cause variation, and potentially misguide the user into taking the wrong actions. Given the growing availability of large datasets from routinely collected databases in healthcare, there is a need to present a review of this problem (which arises because traditional attribute charts only consider within-subgroup variation) and its solutions (which consider within and between-subgroup variation), which involve the use of the well-established measurements chart and the more recently developed attribute charts based on Laney's innovative approach. We close by making some suggestions for practice.

  12. Large superconducting conductors and joints for fusion magnets: From conceptual design to test at full size scale

    International Nuclear Information System (INIS)

    Ciazynski, D.; Duchateau, J.L.; Decool, P.; Libeyre, P.; Turck, B.

    2001-01-01

    A new kind of superconducting conductor, using the so-called cable-in-conduit concept, is emerging mainly involving fusion activity. It is to be noted that at present time no large Nb 3 Sn magnet in the world is operating using this concept. The difficulty of this technology which has now been studied for 20 years, is that it has to integrate major progresses in multiple interconnected new fields such as: large number (1000) of superconducting strands, high current conductors (50 kA), forced flow cryogenics, Nb 3 Sn technology, low loss conductors in pulsed operation, high current connections, high voltage insulation (10 kV), economical and industrial feasibility. CEA was very involved during these last 10 years in this development which took place in the frame of the NET and ITER technological programs. One major milestone was reached in 1998-1999 with the successful tests by our Association of three full size conductor and connection samples in the Sultan facility (Villigen, Switzerland). (author)

  13. The relationship between antibody status to bovine corona virus and bovine respiratory syncytial virus and disease incidence, reproduction and herd characteristics in dairy herds

    Directory of Open Access Journals (Sweden)

    Tråvén Madeleine

    2010-06-01

    Full Text Available Abstract Background Bovine respiratory syncytial virus (BRSV and bovine corona virus (BCV affects cattle worldwide. Our objective was to evaluate the effects of these infections on general health and reproduction parameters measurable on herd level and to explore the association between antibody status and some herd characteristics. Methods We collected a pooled milk sample from five primiparous cows from 79 Swedish dairy herds in September 2006. The samples were analysed for immunoglobulin G antibodies to BCV and BRSV with indirect enzyme-linked immunosorbent assays. Herd level data from 1 September 2005 to 30 August 2006 were accessed retrospectively. The location of the herds was mapped using a geographical information system. Results Ten herds were antibody negative to both viruses and were compared with 69 herds positive to BCV or BRSV or both. Positive herds had a higher (P = 0.001 bulk tank milk somatic cell count (BMSCC compared with negative herds. The medians for all other analyzed health and reproductive parameters were consistently in favour of the herds negative to both viruses although the differences were not statistically significant. A higher proportion (P = 0.01 of herds used professional technicians for artificial insemination, rather than farm personnel, amongst the 33 herds negative to BCV compared with the 46 positive herds. Conclusions Our result shows that herds that were antibody positive to BCV and/or BRSV had a higher BMSCC compared with herds negative to BCV and BRSV. There was also tendency that negative herds had a better general herd health compared with positive. A higher proportion amongst the BCV negative herds used external technicians for AI instead of farm personnel, indicating that it is possible to avoid infection although having regular visits. Negative herds were located in close proximity to positive herds, indicating that local spread and airborne transmission between herds might not be of great

  14. Breed of cow and herd productivity affect milk nutrient recovery in curd, and cheese yield, efficiency and daily production.

    Science.gov (United States)

    Stocco, G; Cipolat-Gotet, C; Gasparotto, V; Cecchinato, A; Bittante, G

    2018-02-01

    Little is known about cheese-making efficiency at the individual cow level, so our objective was to study the effects of herd productivity, individual herd within productivity class and breed of cow within herd by producing, then analyzing, 508 model cheeses from the milk of 508 cows of six different breeds reared in 41 multi-breed herds classified into two productivity classes (high v. low). For each cow we obtained six milk composition traits; four milk nutrient (fat, protein, solids and energy) recovery traits (REC) in curd; three actual % cheese yield traits (%CY); two theoretical %CYs (fresh cheese and cheese solids) calculated from milk composition; two overall cheese-making efficiencies (% ratio of actual to theoretical %CYs); daily milk yield (dMY); and three actual daily cheese yield traits (dCY). The aforementioned phenotypes were analyzed using a mixed model which included the fixed effects of herd productivity, parity, days in milk (DIM) and breed; the random effects were the water bath, vat, herd and residual. Cows reared in high-productivity herds yielded more milk with higher nutrient contents and more cheese per day, had greater theoretical %CY, and lower cheese-making efficiency than low-productivity herds, but there were no differences between them in terms of REC traits. Individual herd within productivity class was an intermediate source of total variation in REC, %CY and efficiency traits (10.0% to 17.2%), and a major source of variation in milk yield and dCY traits (43.1% to 46.3%). Parity of cows was an important source of variation for productivity traits, whereas DIM affected almost all traits. Breed within herd greatly affected all traits. Holsteins produced more milk, but Brown Swiss cows produced milk with higher actual and theoretical %CYs and cheese-making efficiency, so that the two large-framed breeds had the same dCY. Compared with the two large-framed breeds, the small Jersey cows produced much less milk, but with greater actual

  15. Herd Protection from Drinking Water, Sanitation, and Hygiene Interventions.

    Science.gov (United States)

    Fuller, James A; Eisenberg, Joseph N S

    2016-11-02

    Herd immunity arises when a communicable disease is less able to propagate because a substantial portion of the population is immune. Nonimmunizing interventions, such as insecticide-treated bednets and deworming drugs, have shown similar herd-protective effects. Less is known about the herd protection from drinking water, sanitation, and hand hygiene (WASH) interventions. We first constructed a transmission model to illustrate mechanisms through which different WASH interventions may provide herd protection. We then conducted an extensive review of the literature to assess the validity of the model results and identify current gaps in research. The model suggests that herd protection accounts for a substantial portion of the total protection provided by WASH interventions. However, both the literature and the model suggest that sanitation interventions in particular are the most likely to provide herd protection, since they reduce environmental contamination. Many studies fail to account for these indirect effects and thus underestimate the total impact an intervention may have. Although cluster-randomized trials of WASH interventions have reported the total or overall efficacy of WASH interventions, they have not quantified the role of herd protection. Just as it does in immunization policy, understanding the role of herd protection from WASH interventions can help inform coverage targets and strategies that indirectly protect those that are unable to be reached by WASH campaigns. Toward this end, studies are needed to confirm the differential role that herd protection plays across the WASH interventions suggested by our transmission model. © The American Society of Tropical Medicine and Hygiene.

  16. Herd-level association between antimicrobial use and antimicrobial resistance in bovine mastitis Staphylococcus aureus isolates on Canadian dairy farms.

    Science.gov (United States)

    Saini, V; McClure, J T; Scholl, D T; DeVries, T J; Barkema, H W

    2012-04-01

    Surveillance of antimicrobial use and resistance is needed to manage antimicrobial resistance in bacteria. In this study, data were collected on antimicrobial use and resistance in Staphylococcus aureus (n=562), isolated from intramammary infections and (sub)clinical mastitis cases on 89 dairy farms in 4 regions of Canada [Alberta, Ontario, Québec, and the Maritime Provinces (Prince Edward Island, Nova Scotia, and New Brunswick)]. Dairy producers were asked to deposit empty drug containers into specially provided receptacles, and antimicrobial drug use rate was calculated to quantify antimicrobial use. Minimum inhibitory concentrations were determined using the Sensititer bovine mastitis plate system (TREK Diagnostic Systems Inc., Cleveland, OH), containing antimicrobials commonly used for mastitis treatment and control. Multivariable logistic regression models were built to determine herd-level risk factors of penicillin, ampicillin, pirlimycin, penicillin-novobiocin combination, tetracycline and sulfadimethoxine resistance in Staph. aureus isolates. Intramammary administration of the penicillin-novobiocin combination for dry cow therapy was associated with penicillin and ampicillin resistance [odds ratio (OR): 2.17 and 3.10, respectively]. Systemic administration of penicillin was associated with penicillin resistance (OR: 1.63). Intramammary administration of pirlimycin for lactating cow mastitis treatment was associated with pirlimycin resistance as well (OR: 2.07). Average herd parity was associated with ampicillin and tetracycline resistance (OR: 3.88 and 0.02, respectively). Average herd size was also associated with tetracycline resistance (OR: 1.02). Dairy herds in the Maritime region had higher odds of penicillin and lower odds of ampicillin resistance than dairy herds in Québec (OR: 2.18 and 0.19, respectively). Alberta dairy herds had lower odds of ampicillin and sulfadimethoxine resistance than dairy herds in Québec (OR: 0.04 and 0.08, respectively

  17. Quantifying the role of Trojan dams in the between-herd spread of bovine viral diarrhoea virus (BVDv) in Ireland.

    Science.gov (United States)

    Reardon, Fiona; Graham, David A; Clegg, Tracy A; Tratalos, Jamie A; O'Sullivan, Padraig; More, Simon J

    2018-04-01

    A compulsory national programme to eradicate bovine viral diarrhoea virus (BVDv) began in Ireland on 1 January, 2013. The objective of the current study was to quantify the role of Trojan dams (animal(s) not persistently infected (PI) with BVDv but carrying PI foetus(es) and introduced to the herd while pregnant with the PI foetus(es)) in the farm-to-farm spread of BVDv in Ireland, and to identify herd-level risk factors for producing or introducing a Trojan dam. The study population included all BVD+ calves born in Ireland between 1 January, 2013 and 31 December, 2015, along with their dams. BVD+ calves included all calves on the national programme database with an initial positive or inconclusive virus test, without a confirmatory re-test (status BVDPOS) and those with an initial positive or inconclusive test and a positive confirmatory test (status BVDPI). The Trojan status of dams was determined after considering their history of movement and of potential BVDV exposure, relative to a defined window of susceptibility (WOS; days 30-120 of gestation). During 2013-15, there were 29,422 BVD+ birth events to dams that were not themselves BVD+, including 2526 (8.6%) most-likely attributable to Trojan dams. The percentage of these birth events attributable to Trojan dams was significantly different (P Trojan dam. In 2014 and 2015, the percentages were 11.8% and 13.3%, respectively. In 2013, in 7.8% of herds with one or more BVD+ birth to non-BVD+ dams, all of these births were attributable to Trojan dams. In 2014 and 2015, the percentages were 9.2% and 10.7%, respectively. A logistic GEE regression identified dam parity, herd size and an interaction between herd type and season as significant predictors for the birth of a BVD+ calf to a Trojan dam. Significant predictors for the sale of a Trojan dam from BVD+ herds included those selling more than one pregnant female and those with more than 2 BVD+ animals in the herd. Introduction of pregnant adult females is a

  18. Evaluating perspectives for PRRS virus elimination from pig dense areas with a risk factor based herd index.

    Science.gov (United States)

    Fahrion, A S; Beilage, E grosse; Nathues, H; Dürr, S; Doherr, M G

    2014-06-01

    Porcine reproductive and respiratory syndrome virus (PRRSV) is wide-spread in pig populations globally. In many regions of Europe with intensive pig production and high herd densities, the virus is endemic and can cause disease and production losses. This fuels discussion about the feasibility and sustainability of virus elimination from larger geographic regions. The implementation of a program aiming at virus elimination for areas with high pig density is unprecedented and its potential success is unknown. The objective of this work was to approach pig population data with a simple method that could support assessing the feasibility of a sustainable regional PRRSV elimination. Based on known risk factors such as pig herd structure and neighborhood conditions, an index characterizing individual herds' potential for endemic virus circulation and reinfection was designed. This index was subsequently used to compare data of all pig herds in two regions with different pig- and herd-densities in Lower Saxony (North-West Germany) where PRRSV is endemic. Distribution of the indexed herds was displayed using GIS. Clusters of high herd index densities forming potential risk hot spots were identified which could represent key target areas for surveillance and biosecurity measures under a control program aimed at virus elimination. In an additional step, for the study region with the higher pig density (2463 pigs/km(2) farmland), the potential distribution of PRRSV-free and non-free herds during the implementation of a national control program aiming at national virus elimination was modeled. Complex herd and trade network structures suggest that PRRSV elimination in regions with intensive pig farming like that of middle Europe would have to involve legal regulation and be accompanied by important trade and animal movement restrictions. The proposed methodology of risk index mapping could be adapted to areas varying in size, herd structure and density. Interpreted in the

  19. Modelling the economic impact of three lameness causing diseases using herd and cow level evidence.

    Science.gov (United States)

    Ettema, Jehan; Østergaard, Søren; Kristensen, Anders Ringgaard

    2010-06-01

    Diseases to the cow's hoof, interdigital skin and legs are highly prevalent and of large economic impact in modern dairy farming. In order to support farmer's decisions on preventing and treating lameness and its underlying causes, decision support models can be used to predict the economic profitability of such actions. An existing approach of modelling lameness as one health disorder in a dynamic, stochastic and mechanistic simulation model has been improved in two ways. First of all, three underlying diseases causing lameness were modelled: digital dermatitis, interdigital hyperplasia and claw horn diseases. Secondly, the existing simulation model was set-up in way that it uses hyper-distributions describing diseases risk of the three lameness causing diseases. By combining information on herd level risk factors with prevalence of lameness or prevalence of underlying diseases among cows, marginal posterior probability distributions for disease prevalence in the specific herd are created in a Bayesian network. Random draws from these distributions are used by the simulation model to describe disease risk. Hereby field data on prevalence is used systematically and uncertainty around herd specific risk is represented. Besides the fact that estimated profitability of halving disease risk depended on the hyper-distributions used, the estimates differed for herds with different levels of diseases risk and reproductive efficiency. (c) 2010 Elsevier B.V. All rights reserved.

  20. Effects of loading frequency on fatigue crack growth mechanisms in α/β Ti microstructure with large colony size

    International Nuclear Information System (INIS)

    Sansoz, F.; Ghonem, H.

    2003-01-01

    This paper deals with crack tip/microstructure interactions at 520 deg. C in lamellar Ti-6Al-2Sn-4Zr-2Mo-0.1Si (Ti6242) alloy under different fatigue loading frequencies. A series of heat treatments were performed in order to produce large colony microstructures that vary in their lamellar and colony size. Fatigue crack growth (FCG) experiments were conducted on these microstructures at loading frequencies of 10 and 0.05 Hz. The lower frequency was explored with and without imposing a 5 min hold-time at the peak stress level during each loading cycle. Results show that the crack growth behavior is sensitive to the loading frequency. For the same microstructure, the crack growth rate is found to be lower at 10 than at 0.05 Hz. The addition of a hold-time, however, did not alter the FCG rate indicating that creep strain during one loading cycle does not contribute significantly in the crack growth process. It is also shown that variations in lamella and colony size have no effects on the FCG rate except for the early stage of crack propagation. Scanning Electron Microscope examinations are performed on the fracture surface in order to identify the relevant crack growth mechanisms with respect to the loading frequency and the microstructure details. Quasi-cleavage of the α/β colonies along strong planar shear bands is shown to be a major mode of failure under all test condition. At a loading frequency of 10 Hz, the crack path proceeds arbitrary along planes either perpendicular or parallel to the long axis of α lamellae, while at 0.05 Hz, parallel-to-lamellae crack paths become favored. Corresponding differences of crack growth behavior are examined in terms of slip emission at the crack tip and interactions with the microstructure details

  1. Accelerating solidification process simulation for large-sized system of liquid metal atoms using GPU with CUDA

    Energy Technology Data Exchange (ETDEWEB)

    Jie, Liang [School of Information Science and Engineering, Hunan University, Changshang, 410082 (China); Li, KenLi, E-mail: lkl@hnu.edu.cn [School of Information Science and Engineering, Hunan University, Changshang, 410082 (China); National Supercomputing Center in Changsha, 410082 (China); Shi, Lin [School of Information Science and Engineering, Hunan University, Changshang, 410082 (China); Liu, RangSu [School of Physics and Micro Electronic, Hunan University, Changshang, 410082 (China); Mei, Jing [School of Information Science and Engineering, Hunan University, Changshang, 410082 (China)

    2014-01-15

    Molecular dynamics simulation is a powerful tool to simulate and analyze complex physical processes and phenomena at atomic characteristic for predicting the natural time-evolution of a system of atoms. Precise simulation of physical processes has strong requirements both in the simulation size and computing timescale. Therefore, finding available computing resources is crucial to accelerate computation. However, a tremendous computational resource (GPGPU) are recently being utilized for general purpose computing due to its high performance of floating-point arithmetic operation, wide memory bandwidth and enhanced programmability. As for the most time-consuming component in MD simulation calculation during the case of studying liquid metal solidification processes, this paper presents a fine-grained spatial decomposition method to accelerate the computation of update of neighbor lists and interaction force calculation by take advantage of modern graphics processors units (GPU), enlarging the scale of the simulation system to a simulation system involving 10 000 000 atoms. In addition, a number of evaluations and tests, ranging from executions on different precision enabled-CUDA versions, over various types of GPU (NVIDIA 480GTX, 580GTX and M2050) to CPU clusters with different number of CPU cores are discussed. The experimental results demonstrate that GPU-based calculations are typically 9∼11 times faster than the corresponding sequential execution and approximately 1.5∼2 times faster than 16 CPU cores clusters implementations. On the basis of the simulated results, the comparisons between the theoretical results and the experimental ones are executed, and the good agreement between the two and more complete and larger cluster structures in the actual macroscopic materials are observed. Moreover, different nucleation and evolution mechanism of nano-clusters and nano-crystals formed in the processes of metal solidification is observed with large-sized

  2. Using a Herd Profile to Determine Age-Specific Prevalence of Bovine Leukemia Virus in Michigan Dairy Herds

    Directory of Open Access Journals (Sweden)

    Ronald J. Erskine

    2012-01-01

    Full Text Available Enzootic bovine leukosis is a contagious disease of cattle caused by the retrovirus, bovine leukemia virus (BLV and is the most common cause of malignant neoplasm in cattle. In order to facilitate surveillance of this disease in dairy herds, we developed a method to combine ELISA of milk collected during routine production testing with a prescribed sampling of cows that is independent of the proportion of cows within each lactation. In 113 Michigan dairy herds, milk samples from ten cows in each of the 1st, 2nd, 3rd, and ≥4th lactations were analyzed for anti-Bovine Leukemia Virus (BLV antibodies by milk ELISA. For each herd, a BLV herd profile (BHP was calculated as the simple average of the percent of BLV-positive cows within each of the four lactation groups. The mean BHP for all herds was 32.8%, with means of 18.5, 28.8, 39.2, and 44.8% of 1st, 2nd, 3rd, and ≥4th lactation animals infected, respectively. In eight herds, we determined the correlation between the BHP, and true herd prevalence by testing the entire lactating herd (r=0.988,  P<0.0001. The BHP allows discrimination of lactation-specific BLV prevalence within a dairy herd, to help identify risk factors and management plans that may be important in transmission of BLV.

  3. Growing vertical ZnO nanorod arrays within graphite: efficient isolation of large size and high quality single-layer graphene.

    Science.gov (United States)

    Ding, Ling; E, Yifeng; Fan, Louzhen; Yang, Shihe

    2013-07-18

    We report a unique strategy for efficiently exfoliating large size and high quality single-layer graphene directly from graphite into DMF dispersions by growing ZnO nanorod arrays between the graphene layers in graphite.

  4. Percutaneous Ethanol Injection of Unresectable Medium-to-Large-Sized Hepatomas Using a Multipronged Needle: Efficacy and Safety

    International Nuclear Information System (INIS)

    Ho, C.S.; Kachura, J.R.; Gallinger, S.; Grant, D.; Greig, P.; McGilvray, I.; Knox, J.; Sherman, M.; Wong, F.; Wong, D.

    2007-01-01

    Fine needles with an end hole or multiple side holes have traditionally been used for percutaneous ethanol injection (PEI) of hepatomas. This study retrospectively evaluates the safety and efficacy of PEI of unresectable medium-to-large (3.5-9 cm) hepatomas using a multipronged needle and with conscious sedation. Twelve patients, eight men and four women (age 51-77 years; mean: 69) received PEI for hepatomas, mostly subcapsular or exophytic in location with average tumor size of 5.6 cm (range: 3.5-9.0 cm). Patients were consciously sedated and an 18G retractable multipronged needle (Quadrafuse needle; Rex Medical, Philadelphia, PA) was used for injection under real-time ultrasound guidance. By varying the length of the prongs and rotating the needle, the alcohol was widely distributed within the tumor. The progress of ablation was monitored by contrast-enhanced ultrasound, computed tomography (CT) or magnetic resonance imaging (MRI) after each weekly injection and within a month after the final (third) injection and 3 months thereafter. An average total of 63 mL (range: 20-154 ml) of alcohol was injected per patient in an average of 2.3 sessions. Contrast-enhanced CT, ultrasound, or MRI was used to determine the degree of necrosis. Complete necrosis was noted in eight patients (67%), near-complete necrosis (90-99%) in two (16.7%), and partial success (50-89%) in two (16.7%). Follow-up in the first 9 months showed local recurrence in two patients and new lesions in another. There was no mortality. One patient developed renal failure, liver failure, and localized perforation of the stomach. He responded to medical treatment and surgery was not required for the perforation. One patient had severe postprocedural abdominal pain and fever, and another had transient hyperbilirubinemia; both recovered with conservative treatment. PEI with a multipronged needle is a new, safe, and efficacious method in treating medium-to-large-sized hepatocellular carcinoma under conscious

  5. Precise large deviations of aggregate claims in a size-dependent renewal risk model with stopping time claim-number process

    Directory of Open Access Journals (Sweden)

    Shuo Zhang

    2017-04-01

    Full Text Available Abstract In this paper, we consider a size-dependent renewal risk model with stopping time claim-number process. In this model, we do not make any assumption on the dependence structure of claim sizes and inter-arrival times. We study large deviations of the aggregate amount of claims. For the subexponential heavy-tailed case, we obtain a precise large-deviation formula; our method substantially relies on a martingale for the structure of our models.

  6. Evolution of A-Type Macrosegregation in Large Size Steel Ingot After Multistep Forging and Heat Treatment

    Science.gov (United States)

    Loucif, Abdelhalim; Ben Fredj, Emna; Harris, Nathan; Shahriari, Davood; Jahazi, Mohammad; Lapierre-Boire, Louis-Philippe

    2018-06-01

    A-type macrosegregation refers to the channel chemical heterogeneities that can be formed during solidification in large size steel ingots. In this research, a combination of experiment and simulation was used to study the influence of open die forging parameters on the evolution of A-type macrosegregation patterns during a multistep forging of a 40 metric ton (MT) cast, high-strength steel ingot. Macrosegregation patterns were determined experimentally by macroetch along the longitudinal axis of the forged and heat-treated ingot. Mass spectroscopy, on more than 900 samples, was used to determine the chemical composition map of the entire longitudinal sectioned surface. FORGE NxT 1.1 finite element modeling code was used to predict the effect of forging sequences on the morphology evolution of A-type macrosegregation patterns. For this purpose, grain flow variables were defined and implemented in a large scale finite element modeling code to describe oriented grains and A-type segregation patterns. Examination of the A-type macrosegregation showed four to five parallel continuous channels located nearly symmetrical to the axis of the forged ingot. In some regions, the A-type patterns became curved or obtained a wavy form in contrast to their straight shape in the as-cast state. Mass spectrometry analysis of the main alloying elements (C, Mn, Ni, Cr, Mo, Cu, P, and S) revealed that carbon, manganese, and chromium were the most segregated alloying elements in A-type macrosegregation patterns. The observed differences were analyzed using thermodynamic calculations, which indicated that changes in the chemical composition of the liquid metal can affect the primary solidification mode and the segregation intensity of the alloying elements. Finite element modeling simulation results showed very good agreement with the experimental observations, thereby allowing for the quantification of the influence of temperature and deformation on the evolution of the shape of the

  7. How great white sharks nourish their embryos to a large size: evidence of lipid histotrophy in lamnoid shark reproduction.

    Science.gov (United States)

    Sato, Keiichi; Nakamura, Masaru; Tomita, Taketeru; Toda, Minoru; Miyamoto, Kei; Nozu, Ryo

    2016-09-15

    The great white shark (Carcharodon carcharias) exhibits viviparous and oophagous reproduction. A 4950 mm total length (TL) gravid female accidentally caught by fishermen in the Okinawa Prefecture, Southern Japan carried six embryos (543-624 mm TL, three in each uterus). Both uteri contained copious amounts of yellowish viscous uterine fluid (over 79.2 litres in the left uterus), nutrient eggs and broken egg cases. The embryos had yolk stomachs that had ruptured, the mean volume of which was approximately 197.9 ml. Embryos had about 20 rows of potentially functional teeth in the upper and lower jaws. Periodic acid Schiff (PAS)-positive substances were observed on the surface and in the cytoplasm of the epithelial cells, and large, secretory, OsO4-oxidized lipid droplets of various sizes were distributed on the surface of the villous string epithelium on the uterine wall. Histological examination of the uterine wall showed it to consist of villi, similar to the trophonemata of Dasyatidae rays, suggesting that the large amount of fluid found in the uterus of the white shark was likely required for embryo nutrition. We conclude that: (1) the lipid-rich fluid is secreted from the uterine epithelium only in early gestation before the onset of oophagy, (2) the embryos probably use the abundant uterine fluid and encased nutrient eggs for nutrition at this stage of their development, and (3) the uterine fluid is the major source of embryonic nutrition before oophagy onset. This is the first record of the lipid histotrophy of reproduction among all shark species. © 2016. Published by The Company of Biologists Ltd.

  8. How great white sharks nourish their embryos to a large size: evidence of lipid histotrophy in lamnoid shark reproduction

    Directory of Open Access Journals (Sweden)

    Keiichi Sato

    2016-09-01

    Full Text Available The great white shark (Carcharodon carcharias exhibits viviparous and oophagous reproduction. A 4950 mm total length (TL gravid female accidentally caught by fishermen in the Okinawa Prefecture, Southern Japan carried six embryos (543-624 mm TL, three in each uterus. Both uteri contained copious amounts of yellowish viscous uterine fluid (over 79.2 litres in the left uterus, nutrient eggs and broken egg cases. The embryos had yolk stomachs that had ruptured, the mean volume of which was approximately 197.9 ml. Embryos had about 20 rows of potentially functional teeth in the upper and lower jaws. Periodic acid Schiff (PAS-positive substances were observed on the surface and in the cytoplasm of the epithelial cells, and large, secretory, OsO4-oxidized lipid droplets of various sizes were distributed on the surface of the villous string epithelium on the uterine wall. Histological examination of the uterine wall showed it to consist of villi, similar to the trophonemata of Dasyatidae rays, suggesting that the large amount of fluid found in the uterus of the white shark was likely required for embryo nutrition. We conclude that: (1 the lipid-rich fluid is secreted from the uterine epithelium only in early gestation before the onset of oophagy, (2 the embryos probably use the abundant uterine fluid and encased nutrient eggs for nutrition at this stage of their development, and (3 the uterine fluid is the major source of embryonic nutrition before oophagy onset. This is the first record of the lipid histotrophy of reproduction among all shark species.

  9. Long‐term creep rates on the Hayward Fault: evidence for controls on the size and frequency of large earthquakes

    Science.gov (United States)

    Lienkaemper, James J.; McFarland, Forrest S.; Simpson, Robert W.; Bilham, Roger; Ponce, David A.; Boatwright, John; Caskey, S. John

    2012-01-01

    The Hayward fault (HF) in California exhibits large (Mw 6.5–7.1) earthquakes with short recurrence times (161±65 yr), probably kept short by a 26%–78% aseismic release rate (including postseismic). Its interseismic release rate varies locally over time, as we infer from many decades of surface creep data. Earliest estimates of creep rate, primarily from infrequent surveys of offset cultural features, revealed distinct spatial variation in rates along the fault, but no detectable temporal variation. Since the 1989 Mw 6.9 Loma Prieta earthquake (LPE), monitoring on 32 alinement arrays and 5 creepmeters has greatly improved the spatial and temporal resolution of creep rate. We now identify significant temporal variations, mostly associated with local and regional earthquakes. The largest rate change was a 6‐yr cessation of creep along a 5‐km length near the south end of the HF, attributed to a regional stress drop from the LPE, ending in 1996 with a 2‐cm creep event. North of there near Union City starting in 1991, rates apparently increased by 25% above pre‐LPE levels on a 16‐km‐long reach of the fault. Near Oakland in 2007 an Mw 4.2 earthquake initiated a 1–2 cm creep event extending 10–15 km along the fault. Using new better‐constrained long‐term creep rates, we updated earlier estimates of depth to locking along the HF. The locking depths outline a single, ∼50‐km‐long locked or retarded patch with the potential for an Mw∼6.8 event equaling the 1868 HF earthquake. We propose that this inferred patch regulates the size and frequency of large earthquakes on HF.

  10. Effects of different dry period lengths on production and economy in the dairy herd estimated by stochastic simulation

    DEFF Research Database (Denmark)

    Sørensen, J.T.; Enevoldsen, Carsten; Kristensen, T.

    1993-01-01

    exhibited two different rates of voluntary culling for reproductive failure and milk production, and the feeding regimes consisted of grass silage ad lib. and either 8 or 12 kg of concentrates/day in the first 24 weeks of lactation. The economic result was studied under a herd size and a milk quota...

  11. Small size today, aquarium dumping tomorrow: sales of juvenile non-native large fish as an important threat in Brazil

    Directory of Open Access Journals (Sweden)

    André L. B. Magalhães

    2017-12-01

    Full Text Available ABSTRACT Informal sales of large-bodied non-native aquarium fishes (known as “tankbusters” is increasing among Brazilian hobbyists. In this study, we surveyed this non-regulated trade on Facebook® from May 2012 to September 2016, systematically collecting information about the fishes available for trading: species, family, common/scientific names, native range, juvenile length, behavior, number of specimens available in five geographical regions from Brazil. We also assessed the invasion risk of the most frequently sold species using the Fish Invasiveness Screening Test (FIST. We found 93 taxa belonging to 35 families. Cichlidae was the dominant family, and most species were native to South America. All species are sold at very small sizes (< 10.0 cm, and most display aggressive behavior. The hybrid Amphilophus trimaculatus × Amphilophus citrinellus, Astronotus ocellatus, Uaru amphiacanthoides, Osteoglossum bicirrhosum, Cichla piquiti, Pangasianodon hypophthalmus, Datnioides microlepis and Cichla kelberi were the main species available. The southeast region showed the greatest trading activity. Based on biological traits, the FIST indicated that Arapaima gigas, C. kelberi and C. temensis are high-risk species in terms of biological invasions via aquarium dumping. We suggest management strategies such as trade regulations, monitoring, euthanasia and educational programs to prevent further introductions via aquarium dumping.

  12. Characterisation of Late Bronze Age large size shield nails by EDXRF, micro-EDXRF and X-ray digital radiography

    International Nuclear Information System (INIS)

    Figueiredo, E.; Araujo, M.F.; Silva, R.J.C.; Senna-Martinez, J.C.; Ines Vaz, J.L.

    2011-01-01

    In the present study six exceptional large size metallic nails, a dagger and a sickle from the Late Bronze Age archaeological site of Figueiredo das Donas (Central Portugal) have been analysed by EDXRF, micro-EDXRF and X-ray digital radiography for the study of material composition and technology of fabrication. The combination of these analytical and examination techniques showed that all artefacts are made of bronze with As, Sb and Pb impurities, and that the nails were most likely manufactured using the casting-on technique. These results reinforce the use of binary bronze by Late Bronze Age in the region, and the incorporation of new fabrication technologies that resulted from ancient spheres of interaction. - Highlights: → EDXRF, micro-EDXRF and X-ray digital radiography in cultural heritage studies. → Archaeometallurgical study of a Late Bronze Age artefact collection from Portugal. → Practise of a specific and traditional bronze metallurgy. → Appearance of technological innovations as the casting-on technique.

  13. Boys who pee the farthest have a large hollow head, a thin skin, and medium-size manhood

    Science.gov (United States)

    Attinger, Daniel; Lee, Vincent

    2016-11-01

    Following a recent trend of scientific studies on artwork, we study here the thermodynamics of a jetting thermometer made of ceramic, related to the Chinese tea culture. The thermometer represents a boy who "urinates" shortly after hot water is poured onto his head. Long jetting distance indicates if the water temperature is hot enough to brew tea. Here, a thermofluid model describes the jetting phenomenon of that pee-pee boy. The study demonstrates how thermal expansion of an interior air pocket causes jetting. The validity of assumptions underlying the Hagen-Poiseuille flow is discussed for urethra of finite length. A thermodynamic potential is shown to define maximum jetting velocity. Seven optimization criteria to maximize jetting distance are provided, including two dimensionless numbers. The dimensionless numbers are obtained by comparing the time scales of the internal pressure buildup due to heating, with that of pressure relief due to jetting. Optimization results show that longer jets are produced by large individuals, with low body mass index, with a boyhood of medium size inclined at an angle π/4. Analogies are drawn with pissing contests among humans and lobsters. The study ends by noting similitudes of working principle between that politically incorrect thermometer and Galileo Galilei's thermoscope.

  14. Ni foam assisted synthesis of high quality hexagonal boron nitride with large domain size and controllable thickness

    Science.gov (United States)

    Ying, Hao; Li, Xiuting; Li, Deshuai; Huang, Mingqiang; Wan, Wen; Yao, Qian; Chen, Xiangping; Wang, Zhiwei; Wu, Yanqing; Wang, Le; Chen, Shanshan

    2018-04-01

    The scalable synthesis of two-dimensional (2D) hexagonal boron nitride (h-BN) is of great interest for its numerous applications in novel electronic devices. Highly-crystalline h-BN films, with single-crystal sizes up to hundreds of microns, are demonstrated via a novel Ni foam assisted technique reported here for the first time. The nucleation density of h-BN domains can be significantly reduced due to the high boron solubility, as well as the large specific surface area of the Ni foam. The crystalline structure of the h-BN domains is found to be well aligned with, and therefore strongly dependent upon, the underlying Pt lattice orientation. Growth-time dependent experiments confirm the presence of a surface mediated self-limiting growth mechanism for monolayer h-BN on the Pt substrate. However, utilizing remote catalysis from the Ni foam, bilayer h-BN films can be synthesized breaking the self-limiting effect. This work provides further understanding of the mechanisms involved in the growth of h-BN and proposes a facile synthesis technique that may be applied to further applications in which control over the crystal alignment, and the numbers of layers is crucial.

  15. Theoretical simulation and analysis of large size BMP-LSC by 3D Monte Carlo ray tracing model

    Institute of Scientific and Technical Information of China (English)

    Feng Zhang; Ning-Ning Zhang; Yi Zhang; Sen Yan; Song Sun; Jun Bao; Chen Gao

    2017-01-01

    Luminescent solar concentrators (LSC) can reduce the area of solar cells by collecting light from a large area and concentrating the captured light onto relatively small area photovoltaic (PV) cells,and thereby reducing the cost of PV electricity generation.LSCs with bottom-facing cells (BMP-LSC) can collect both direct light and indirect light,so further improving the efficiency of the PV cells.However,it is hard to analyze the effect of each parameter by experiment because there are too many parameters involved in the BMP-LSC.In this paper,all the physical processes of the light transmission and collection in the BMP-LSC were analyzed.A three-dimensional Monte Carlo ray tracing program was developed to study the transmission of photons in the LSC.A larger-size LSC was simulated,and the effects of dye concentration,the LSC thickness,the cell area,and the cell distance were systematically analyzed.

  16. Depletion of trophy large-sized sharks populations of the Argentinean coast, south-western Atlantic: insights from fishers' knowledge

    Directory of Open Access Journals (Sweden)

    Alejo Irigoyen

    Full Text Available Abstract Globally, sharks are impacted by a wide range of human activities, resulting in many populations being depleted. Trophy large-sized sharks of the Argentinean coast, the sand-tiger Carcharias taurus , the copper Carcharhinus brachyurus and the sevengill shark Notorynchus cepedianus are under intense sport and artisanal fishing since the 50's decade. However, the current and historical information for the assessment of its populations status is scarce. The aim of this work was to analyze the status of conservation of these species through the gathering of expert fishermen knowledge (FK on semi-structured interviews. Abundance variation perception between the beginning and the end of fishermen careers revealed a critical status for the species study (means variation between -77 and -90 %. Furthermore, a best day's catch analysis reinforce this result in the case of the sand tiger shark. The school shark Galeorhinus galeus was included on this work with the objective of contrast FK with formal information available of catch-per-unit-effort (CPUE time series. Both sources of information, despite are not comparable, shows declines ~ - 80%. The critical conservation situation of study species needs urgent management action, particularly for the san tiger shark which could became regionally extinct before the reaction of stakeholders occurs.

  17. Mammals of medium and large size in Santa Rita do Sapucaí, Minas Gerais, southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Eduardo, A. A.

    2009-01-01

    Full Text Available The diversity of Brazilian vertebrates is regarded among the highest in the world. However, the biologicaldiversity is still mostly unknown and a good part of it is seriously threatened by human activities. This study aimed toinventory the medium and large size mammals present in the Reserva Biológica de Santa Rita do Sapucaí, an Atlanticforest reserve located in Santa Rita do Sapucaí, southeastern Brazil. Sand-plots, photographic traps and searches foranimal tracks on pre-existent trails in the area, were carried out once every two months between May 2006 andFebruary 2007. The sand-plots and tracks were inspected during five consecutive days per sampling. We obtained 108records of 15 species, mostly of carnivorans. Two confirmed species are threatened with extinction in Brazil (Callithrixaurita and Leopardus pardalis. The results suggest that the sampled reserve has high species richness and plays animportant role in conservation of mammals in this landscape, including species threatened with extinction.

  18. Development of 3D Visualization Technology for Medium-and Large-sized Radioactive Metal Wastes from Decommissioning Nuclear Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Lee, A Rim; Park, Chan Hee; Lee, Jung Min; Kim, Rinah; Moon, Joo Hyun [Dongguk Univ., Gyongju (Korea, Republic of)

    2013-10-15

    The most important point of decommissioning nuclear facilities and nuclear power plants is to spend less money and do this process safely. In order to perform a better decommissioning nuclear facilities and nuclear power plants, a data base of radioactive waste from decontamination and decommissioning of nuclear facilities should be constructed. This data base is described herein, from the radioactive nuclide to the shape of component of nuclear facilities, and representative results of the status and analysis are presented. With the increase in number of nuclear facilities at the end of their useful life, the demand of decommissioning technologies will continue to grow for years to come. This analysis of medium-and large-sized radioactive metal wastes and 3D visualization technology of the radioactive metal wastes using the 3D-SCAN are planned to be used for constructing data bases. The data bases are expected to be used on development of the basic technologies for decommissioning nuclear facilities 4 session.

  19. Consecutive Short-Scan CT for Geological Structure Analog Models with Large Size on In-Situ Stage.

    Science.gov (United States)

    Yang, Min; Zhang, Wen; Wu, Xiaojun; Wei, Dongtao; Zhao, Yixin; Zhao, Gang; Han, Xu; Zhang, Shunli

    2016-01-01

    For the analysis of interior geometry and property changes of a large-sized analog model during a loading or other medium (water or oil) injection process with a non-destructive way, a consecutive X-ray computed tomography (XCT) short-scan method is developed to realize an in-situ tomography imaging. With this method, the X-ray tube and detector rotate 270° around the center of the guide rail synchronously by switching positive and negative directions alternately on the way of translation until all the needed cross-sectional slices are obtained. Compared with traditional industrial XCTs, this method well solves the winding problems of high voltage cables and oil cooling service pipes during the course of rotation, also promotes the convenience of the installation of high voltage generator and cooling system. Furthermore, hardware costs are also significantly decreased. This kind of scanner has higher spatial resolution and penetrating ability than medical XCTs. To obtain an effective sinogram which matches rotation angles accurately, a structural similarity based method is applied to elimination of invalid projection data which do not contribute to the image reconstruction. Finally, on the basis of geometrical symmetry property of fan-beam CT scanning, a whole sinogram filling a full 360° range is produced and a standard filtered back-projection (FBP) algorithm is performed to reconstruct artifacts-free images.

  20. Herd health and management of dairy cow

    Science.gov (United States)

    Ćaǧlayan, Alper; Yüca, Songül

    2016-04-01

    Herd management requires multidisciplinary practices including animal feeding, gynecology, artificial insemination, immunology, and similar topics. Animal feeding is the most delicate subject as the fodder expense is 70% of the farm cost and as nearly all of the metabolic diseases arising out as health problem are because of misfeeding. However, a business organization's being able to maintain making profit will be possible by taking a healthy calf from breeding herd every year. For this reason, precision registrations of birth and artificial insemination, following-up pregnant state of animals, and making the other animals pregnant as soon as possible should be primary aim. It should not be forgotten that diarrhea and pneumonia in calves are among the most frequently witnessed infection related health problems. Mastitis, metritis and foot diseases take an important place in mature cows. These diseases can be minimized by vaccinations that are done properly and in suitable time, in-service training of staffs, making shelters suitable for animals welfare, and improving the hygienic conditions.

  1. Signal formation processes in Micromegas detectors and quality control for large size detector construction for the ATLAS new small wheel

    Energy Technology Data Exchange (ETDEWEB)

    Kuger, Fabian

    2017-07-31

    and production feasibility resulted in the selection of the proposed mesh by the NSW community and its full scale industrial manufacturing. The successful completion of both tasks were important milestones towards the construction of large size Micromegas detectors clearing the path for NSW series production.

  2. Signal formation processes in Micromegas detectors and quality control for large size detector construction for the ATLAS new small wheel

    International Nuclear Information System (INIS)

    Kuger, Fabian

    2017-01-01

    and production feasibility resulted in the selection of the proposed mesh by the NSW community and its full scale industrial manufacturing. The successful completion of both tasks were important milestones towards the construction of large size Micromegas detectors clearing the path for NSW series production.

  3. Contribution of large-sized primary sensory neuronal sensitization to mechanical allodynia by upregulation of hyperpolarization-activated cyclic nucleotide gated channels via cyclooxygenase 1 cascade.

    Science.gov (United States)

    Sun, Wei; Yang, Fei; Wang, Yan; Fu, Han; Yang, Yan; Li, Chun-Li; Wang, Xiao-Liang; Lin, Qing; Chen, Jun

    2017-02-01

    Under physiological state, small- and medium-sized dorsal root ganglia (DRG) neurons are believed to mediate nociceptive behavioral responses to painful stimuli. However, recently it has been found that a number of large-sized neurons are also involved in nociceptive transmission under neuropathic conditions. Nonetheless, the underlying mechanisms that large-sized DRG neurons mediate nociception are poorly understood. In the present study, the role of large-sized neurons in bee venom (BV)-induced mechanical allodynia and the underlying mechanisms were investigated. Behaviorally, it was found that mechanical allodynia was still evoked by BV injection in rats in which the transient receptor potential vanilloid 1-positive DRG neurons were chemically deleted. Electrophysiologically, in vitro patch clamp recordings of large-sized neurons showed hyperexcitability in these neurons. Interestingly, the firing pattern of these neurons was changed from phasic to tonic under BV-inflamed state. It has been suggested that hyperpolarization-activated cyclic nucleotide gated channels (HCN) expressed in large-sized DRG neurons contribute importantly to repeatedly firing. So we examined the roles of HCNs in BV-induced mechanical allodynia. Consistent with the overexpression of HCN1/2 detected by immunofluorescence, HCNs-mediated hyperpolarization activated cation current (I h ) was significantly increased in the BV treated samples. Pharmacological experiments demonstrated that the hyperexcitability and upregulation of I h in large-sized neurons were mediated by cyclooxygenase-1 (COX-1)-prostaglandin E2 pathway. This is evident by the fact that the COX-1 inhibitor significantly attenuated the BV-induced mechanical allodynia. These results suggest that BV can excite the large-sized DRG neurons at least in part by increasing I h through activation of COX-1. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Relationships between functional herd life and conformation traits in ...

    African Journals Online (AJOL)

    The genetic relationship between conformation traits and functional herd life of the South African Jersey population was investigated. Data on conformation traits (n = 46 238) and functional herd life (n = 90 530) on registered South African Jersey cows calving between 1989 and 2008 were obtained from the Integrated ...

  5. Maximum herd efficiency in meat production I. Optima for slaughter ...

    African Journals Online (AJOL)

    Profit rate for a meat production enterprise can be decomposedinto the unit price for meat and herd ... supply and demand, whereas breeding improvement is gen- ... Herd efficiency is total live mass for slaughter divided by costs .... tenance and above-maintenance components by Dickerson, and ..... Growth and productivity.

  6. Breakeven costs for embryo transfer in a commercial dairy herd.

    Science.gov (United States)

    Ferris, T A; Troyer, B W

    1987-11-01

    Differences in Estimated Breeding Values expressed in dollars were compared by simulation of two, 100-cow, closed herds. One herd practiced normal intensity of female selection. The other herd generated various herd replacements by embryo transfer by varying 1) selection rate of embryo transfer dams and 2) numbers of daughters per dam from which embryos were transferred, while varying the merit of mates of embryo transfer dams. Estimated Breeding Value dollars were compounded each generation and regressed to remove age adjustments and added feed and health costs. Beginning values in both herds included a standard deviation of 55 Cow Index dollars, herd average of -23 Cow Index dollars, and a 120 Predicted Difference dollars for mates of dams not embryo transferred. Average merit of all sires used increased $12 per year. Herd calving rate (.70), proportion females (.5), calf loss (.15), and heifer survival rate (.83) were used. Breakeven cost per embryo transfer cow entering the milking herd was computed by Net Present Value analysis using a 10% discount rate over 10 and 20 yr. Breakeven cost or the maximum expense that would allow a 10% return on the expenditure ranged from $135 to $510 per surviving cow, $24 to $125 per transfer, $47 to $178 per pregnancy, and $81 to $357 per female calf born. As the number of replacements resulting from embryo transfer increased, breakeven cost per embryo transfer cow decreased due to diminishing return.

  7. 9 CFR 77.35 - Interstate movement from accredited herds.

    Science.gov (United States)

    2010-01-01

    ... accredited herd. If a group of captive cervids from an accredited herd is being moved interstate together to... cervids is being moved together, the entire group must be isolated from all other livestock during the... from isolation; or (3) If the captive cervid to be added is not being moved directly from a classified...

  8. Stochastic models to simulate paratuberculosis in dairy herds

    DEFF Research Database (Denmark)

    Nielsen, S.S.; Weber, M.F.; Kudahl, Anne Margrethe Braad

    2011-01-01

    in the design of certification, surveillance, and control strategies for paratuberculosis in cattle herds. A detailed comparison is made between the Dutch JohneSSim and the Danish PTB-Simherd, using the same context of a set of control strategies in a typical Dutch/Danish herd. The conclusion is that while...

  9. Financial aspects of veterinary herd health management programmes

    NARCIS (Netherlands)

    Ifende, V.I.; Derks, M.; Hooijer, G.A.; Hogeveen, H.

    2014-01-01

    Veterinary herd health management (VHHM) programmes are meant to support herd health and farmers’ income (Brand and Guard 1996). They were introduced in the Netherlands in the 1970s (Sol and Renkema 1984) and at present many veterinarians provide them to farmers. VHHM comprises a basic structure of

  10. Patterns of herding and their occurrence in an online setting

    NARCIS (Netherlands)

    Langley, D.J.; Hoeve, M.C.; Ortt, J.R.; Pals, N.; Vecht, B. van der

    2014-01-01

    When groups of consumers share information or express their opinions about products and services, their attitudes or behavior sometime align without centralized coordination, a phenomenon known as herding. Building on pattern-based explanations of herding from the cognitive science literature, we

  11. Genetic value of herd life adjusted for milk production.

    Science.gov (United States)

    Allaire, F R; Gibson, J P

    1992-05-01

    Cow herd life adjusted for lactational milk production was investigated as a genetic trait in the breeding objective. Under a simple model, the relative economic weight of milk to adjusted herd life on a per genetic standard deviation basis was equal to CVY/dCVL where CVY and CVL are the genetic coefficients of variation of milk production and adjusted herd life, respectively, and d is the depreciation per year per cow divided by the total fixed costs per year per cow. The relative economic value of milk to adjusted herd life at the prices and parameters for North America was about 3.2. An increase of 100-kg milk was equivalent to 2.2 mo of adjusted herd life. Three to 7% lower economic gain is expected when only improved milk production is sought compared with a breeding objective that included both production and adjusted herd life for relative value changed +/- 20%. A favorable economic gain to cost ratio probably exists for herd life used as a genetic trait to supplement milk in the breeding objective. Cow survival records are inexpensive, and herd life evaluations from such records may not extend the generation interval when such an evaluation is used in bull sire selection.

  12. Control of Yersinia enterocolitica in pigs at herd level

    DEFF Research Database (Denmark)

    Skjerve, Eystein; Lium, Bjørn; Nielsen, Bent

    1998-01-01

    of slaughter pigs (OR = 0.44) also lowered the herd prevalence. The most expressed risk factor was using an own farm vehicle for transport of slaughter pigs to abattoirs (OR = 12.92). Separation between clean and unclean section in herds (OR = 2.67), daily observations of a cat with kittens on the farm (OR = 2...

  13. Patterns of Herding and their Occurrence in an Online Setting

    NARCIS (Netherlands)

    Langley, David J.; Hoeve, Maarten C.; Ortt, J. Roland; Pals, Nico; van der Vecht, Bob

    When groups of consumers share information or express their opinions about products and services, their attitudes or behavior sometime align without centralized coordination, a phenomenon known as herding. Building on pattern-based explanations of herding from the cognitive science literature, we

  14. Veterinary dairy herd fertility service provision in seasonal and non-seasonal dairy industries - a comparison

    Directory of Open Access Journals (Sweden)

    Mee JF

    2010-04-01

    Full Text Available Abstract The decline in dairy herd fertility internationally has highlighted the limited impact of traditional veterinary approaches to bovine fertility management. Three questionnaire surveys were conducted at buiatrics conferences attended by veterinary practitioners on veterinary dairy herd fertility services (HFS in countries with a seasonal (Ireland, 47 respondents and non-seasonal breeding model (The Netherlands, 44 respondents and Portugal, 31 respondents. Of the 122 respondents, 73 (60% provided a HFS and 49 (40% did not. The majority (76% of all practitioners who responded stated that bovine fertility had declined in their practice clients' herds with inadequate cow management, inadequate nutrition and increased milk yield as the most important putative causes. The type of clients who adopted a herd fertility service were deemed more educated than average (70% of respondents, and/or had fertility problems (58% and/or large herds (53%. The main components of this service were routine postpartum examinations (95% of respondents, fertility records analysis (75% and ultrasound pregnancy examinations (69%. The number of planned visits per annum varied between an average of four in Ireland, where breeding is seasonal, and 23 in Portugal, where breeding is year-round. The benefits to both the practitioner and their clients from running a HFS were cited as better fertility, financial rewards and job satisfaction. For practitioners who did not run a HFS the main reasons given were no client demand (55% and lack of fertility records (33%. Better economic evidence to convince clients of the cost-benefit of such a service was seen as a major constraint to adoption of this service by 67% of practitioners.

  15. Estimation of the frequency of Q fever in sheep, goat and cattle herds in France: results of a 3-year study of the seroprevalence of Q fever and excretion level of Coxiella burnetii in abortive episodes.

    Science.gov (United States)

    Gache, K; Rousset, E; Perrin, J B; DE Cremoux, R; Hosteing, S; Jourdain, E; Guatteo, R; Nicollet, P; Touratier, A; Calavas, D; Sala, C

    2017-11-01

    A study was carried out, from 2012 to 2015, in 10 French départements to estimate the serological prevalence of Q fever and the frequency of abortive episodes potentially related to Coxiella burnetii in a large sample of cattle, sheep and goat herds. The serological survey covered 731 cattle, 522 sheep and 349 goat herds, randomly sampled. The frequency of abortive episodes potentially related to C. burnetii was estimated by investigating series of abortions in 2695 cattle, 658 sheep and 105 goat herds using quantitative polymerase chain reaction analyses and complementary serological results when needed. The average between-herd seroprevalence was significantly lower for cattle (36·0%) than for sheep (55·7%) and goats (61·0%) and significantly higher for dairy herds (64·9% for cattle and 75·6% for sheep) than for meat herds (18·9% for cattle and 39·8% for sheep). Within-herd seroprevalence was also significantly higher for goats (41·5%) than for cattle (22·2%) and sheep (25·7%). During the study period, we estimated that 2·7% (n = 90), 6·2% (n = 48) and 16·7% (n = 19) of the abortive episodes investigated could be 'potentially related to C. burnetii'in cattle, sheep and goat herds, respectively. Overall, strong variability was observed between départements and species, suggesting that risk factors such as herd density and farming practices play a role in disease transmission and maintenance.

  16. Dairy operation management practices and herd milk production.

    Science.gov (United States)

    Losinger, W C; Heinrichs, A J

    1996-03-01

    A national US survey collected data on herd milk production and management of Holstein herds. Step-wise selection identified management practices that were related to herd milk production using only operations that calculated herd milk production as well as using data from all operations. Results were similar. Milk production was highest in the West. Operations with 25% registered cattle had higher production than operations with no registered cattle. Dairy operations that reported a mean BW > 545 kg at first calving had higher mean milk production than operations with a mean BW or = 27 mo at first calving. In addition, use of the following management practices was associated with higher rolling herd average milk production: calves born in individual areas in buildings, calves hand-fed first colostrum, starter grain fed to preweaned calves, ionophores fed to heifers from birth to first calving, DHIA record-keeping system used, computerized records, and no new cattle introduced in the previous 12 mo.

  17. Modeling salmonella Dublin into the dairy herd simulation model Simherd

    DEFF Research Database (Denmark)

    Kudahl, Anne Braad

    2010-01-01

    Infection with Salmonella Dublin in the dairy herd and effects of the infection and relevant control measures are currently being modeled into the dairy herd simulation model called Simherd. The aim is to compare the effects of different control strategies against Salmonella Dublin on both within...... of the simulations will therefore be used for decision support in the national surveillance and eradication program against Salmonella Dublin. Basic structures of the model are programmed and will be presented at the workshop. The model is in a phase of face-validation by a group of Salmonella......-herd- prevalence and economy by simulations. The project Dublin on both within-herd- prevalence and economy by simulations. The project is a part of a larger national project "Salmonella 2007 - 2011" with the main objective to reduce the prevalence of Salmonella Dublin in Danish Dairy herds. Results...

  18. Diagnostic studies of abortion in Danish dairy herds

    DEFF Research Database (Denmark)

    Agerholm, J.S.; Willadsen, C. M.; Nielsen, Thomas Krogh

    1997-01-01

    Diagnostic findings in 218 aborted bovine foetuses are reported. The materials were examined in a matched case-control study of 69 Danish dairy herds with a sudden increase in the number of abortions and a corresponding 69 control herds. Foetuses aborted during the subsequent 6-month period were...... examined to identify the cause of abortion if possible. A total of 186 specimens were submitted from case herds and 32 from control herds. A likely cause of abortion was diagnosed in 73 foetuses. The most common cause was bovine viral diarrhoea virus (BVDV: 13%) followed by Neospora caninum infection (10......%), mycosis (5%) and Bacillus licheniformis infection (4%). Foetal and/or placental lesions were found in a further 27 cases. Only BVDV infection and neosporosis were diagnosed in more than one foetus per herd and only protozoal associated abortions occurred significantly more frequently in the case, rather...

  19. The main postulates of adaptive correction of distortions of the wave front in large-size optical systems

    Directory of Open Access Journals (Sweden)

    V. V. Sychev

    2014-01-01

    Full Text Available In the development of optical telescopes, striving to increase the penetrating power of a telescope has been always the main trend. A real way to solve this problem is to raise the quality of the image (reduction of the image angular size under real conditions of distorting factor and increase a diameter of the main mirror. This is counteracted by the various distorting factors or interference occurring in realtime use of telescopes, as well as by complicated manufacturing processes of large mirrors.It is shown that the most effective method to deal with the influence of distorting factors on the image quality in the telescope is the minimization (through selecting the place to mount a telescope and choosing the rational optical scheme, creating materials and new technologies, improving a design, unloading the mirrors, mounting choice, etc., and then the adaptive compensation of remaining distortions.It should be noted that a domestic concept to design large-sized telescopes allows us to use, in our opinion, the most efficient ways to do this. It means to abandon the creation of "an absolutely rigid and well-ordered" design, providing the passively aligned state telescope optics under operating conditions. The design must just have such a level of residual deformations that their effect can be efficiently compensated by the adaptive system using the segmented elements of the primary mirror and the secondary mirror as a corrector.It has been found that in the transmission optical systems to deliver laser power to a remote object, it is necessary not only to overcome the distorting effect of factors inherent in optical information systems, but, additionally, find a way to overcome a number of new difficulties. The main ones have been identified to be as follows:• the influence of laser radiation on the structure components and the propagation medium and, as a consequence, the opposite effect of the structure components and the propagation

  20. Behavioural processes in social context: female abductions, male herding and female grooming in hamadryas baboons.

    Science.gov (United States)

    Polo, Pablo; Colmenares, Fernando

    2012-06-01

    The formation of bonds between strangers is an event that occurs routinely in many social animals, including humans, and, as social bonds in general, they affect the individuals' welfare and biological fitness. The present study was motivated by an interest in the behavioural processes that drive bond formation in a social context of hostility, in which the incumbent partners vary greatly in physical power and reproductive interests, a situation in which individuals of many group-living species find themselves often throughout their lives. We focused on the quantitative analysis of female abductions via male aggressive herding in a nonhuman primate, the hamadryas baboon, in which intersexual bonds are known to be strong. We tested three hypotheses informed by sexual conflict/sexual coercion theory (male herding-as-conditioning and female grooming-as-appeasement) and by socioecological theory (unit size and female competition). The results supported the predictions: males resorted to coercive tactics (aggressive herding) with abducted females, and abducted females elevated the amount of grooming directed at their new unit males; in fact, they escaped from the otherwise negative effect of unit size on female-to-male grooming. These findings reveal that conflicts of interest are natural ingredients underpinning social bonds and that resorting to coercive aggression may be an option especially when partners differ greatly in their physical power. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Assessing the impact of large-scale computing on the size and complexity of first-principles electromagnetic models

    International Nuclear Information System (INIS)

    Miller, E.K.

    1990-01-01

    There is a growing need to determine the electromagnetic performance of increasingly complex systems at ever higher frequencies. The ideal approach would be some appropriate combination of measurement, analysis, and computation so that system design and assessment can be achieved to a needed degree of accuracy at some acceptable cost. Both measurement and computation benefit from the continuing growth in computer power that, since the early 1950s, has increased by a factor of more than a million in speed and storage. For example, a CRAY2 has an effective throughput (not the clock rate) of about 10 11 floating-point operations (FLOPs) per hour compared with the approximate 10 5 provided by the UNIVAC-1. The purpose of this discussion is to illustrate the computational complexity of modeling large (in wavelengths) electromagnetic problems. In particular the author makes the point that simply relying on faster computers for increasing the size and complexity of problems that can be modeled is less effective than might be anticipated from this raw increase in computer throughput. He suggests that rather than depending on faster computers alone, various analytical and numerical alternatives need development for reducing the overall FLOP count required to acquire the information desired. One approach is to decrease the operation count of the basic model computation itself, by reducing the order of the frequency dependence of the various numerical operations or their multiplying coefficients. Another is to decrease the number of model evaluations that are needed, an example being the number of frequency samples required to define a wideband response, by using an auxiliary model of the expected behavior. 11 refs., 5 figs., 2 tabs

  2. Upper limits to americium concentration in large sized sodium-cooled fast reactors loaded with metallic fuel

    International Nuclear Information System (INIS)

    Zhang, Youpeng; Wallenius, Janne

    2014-01-01

    Highlights: • The americium transmutation capability of Integral Fast Reactor was investigated. • The impact from americium introduction was parameterized by applying SERPENT Monte Carlo calculations. • Higher americium content in metallic fuel leads to a power penalty, preserving consistent safety margins. - Abstract: Transient analysis of a large sized sodium-cooled reactor loaded with metallic fuel modified by different fractions of americium have been performed. Unprotected loss-of-offsite power, unprotected loss-of-flow and unprotected transient-over-power accidents were simulated with the SAS4A/SASSYS code based on the geometrical model of an IFR with power rating of 2500 MW th , using safety parameters obtained with the SERPENT Monte Carlo code. The Ti-modified austenitic D9 steel, having higher creep rupture strength, was considered as the cladding and structural material apart from the ferritic/martensitic HT9 steel. For the reference case of U–12Pu–1Am–10Zr fuel at EOEC, the margin to fuel melt during a design basis condition UTOP is about 50 K for a maximum linear rating of 30 kW/m. In order to maintain a margin of 50 K to fuel failure, the linear power rating has to be reduced by ∼3% and 6% for 2 wt.% and 3 wt.% Am introduction into the fuel respectively. Hence, an Am concentration of 2–3 wt.% in the fuel would lead to a power penalty of 3–6%, permitting a consumption rate of 3.0–5.1 kg Am/TW h th . This consumption rate is significantly higher than the one previously obtained for oxide fuelled SFRs

  3. Association between stall surface and some animal welfare measurements in freestall dairy herds using recycled manure solids for bedding.

    Science.gov (United States)

    Husfeldt, A W; Endres, M I

    2012-10-01

    The objective of this cross-sectional study was to investigate the association between stall surface and some animal welfare measurements in upper Midwest US dairy operations using recycled manure solids as bedding material. The study included 34 dairy operations with herd sizes ranging from 130 to 3,700 lactating cows. Forty-five percent of the herds had mattresses and 55% had deep-bedded stalls. Farms were visited once between July and October 2009. At the time of visit, at least 50% of the cows in each lactating pen were scored for locomotion, hygiene, and hock lesions. On-farm herd records were collected for the entire year and used to investigate mortality, culling, milk production, and mastitis incidence. Stall surface was associated with lameness and hock lesion prevalence. Lameness prevalence (locomotion score ≥ 3 on a 1 to 5 scale) was lower in deep-bedded freestalls (14.4%) than freestalls with mattresses (19.8%). Severe lameness prevalence (locomotion score ≥ 4) was also lower for cows housed in deep-bedded freestalls (3.6%) than for cows housed in freestalls with mattresses (5.9%). In addition, the prevalence of hock lesions (hock lesion scores ≥ 2 on a 1 to 3 scale, with 1=no lesion, 2=hair loss or mild lesion, and 3=swelling or severe lesion) and severe hock lesions (hock lesion score=3) was lower in herds with deep-bedded freestalls (49.4%; 6.4%) than in herds with mattresses (67.3%; 13.2%). Herd turnover rates were not associated with stall surface; however, the percentage of removals due to voluntary (low milk production, disposition, and dairy) and involuntary (death, illness, injury, and reproductive) reasons was different between deep-bedded and mattress-based freestalls. Voluntary removals averaged 16% of all herd removals in deep-bedded herds, whereas in mattress herds, these removals were 8%. Other welfare measurements such as cow hygiene, mortality rate, mastitis incidence, and milk production were not associated with stall surface

  4. Seroepidemiology of bovine viral diarrhoea virus (BVDV in the Adamawa Region of Cameroon and use of the SPOT test to identify herds with PI calves.

    Directory of Open Access Journals (Sweden)

    Ian G Handel

    Full Text Available Bovine viral diarrhoea, caused by the bovine viral diarrhoea virus (BVDV in the Pestivirus genus of the Flaviviridae, is one of the most important diseases of cattle world wide causing poor reproductive performance in adult cattle and mucosal disease in calves. In addition it causes immunosuppression and increased susceptibility to other infections, the impact of which is uncertain, particularly in sub-Saharan Africa where animals are exposed to a much wider range and higher intensity of infections compared to Europe. There are no previous estimates of the seroprevalence of BVDV in cattle in Cameroon. This paper describes the serological screening for antibodies to BVDV and antigen of BVDV in a cattle population in the Adamawa Region of Cameroon in 2000. The estimates of herd-level and within herd seroprevalences adjusted for test imperfections were 92% and 30% respectively and 16.5% of herds were classed as having a persistently infected calf (PI in the herd within the last year based on the "spot" test approach. There was evidence of clustering of herds with PI calves across the north and west of the Region which corresponds with the higher cattle density areas and of self-clearance of infection from herds. A multivariable model was developed for the risk of having a PI calf in the herd; proximity to antelope, owning a goat, mixing with > 10 other herds at grazing and the catchment area of the veterinary centre the herd was registered at were all significant risk factors. Very little is known about BVDV in sub-Saharan Africa and these high seroprevalences suggest that there is a large problem which may be having both direct impacts on fertility and neonate mortality and morbidity and also indirect effects through immunosuppression and susceptibility to other infections. Understanding and accounting for BVDV should be an important component of epidemiological studies of other diseases in sub-Saharan Africa.

  5. Analysis of Large Seeds from Three Different Medicago truncatula Ecotypes Reveals a Potential Role of Hormonal Balance in Final Size Determination of Legume Grains

    Directory of Open Access Journals (Sweden)

    Kaustav Bandyopadhyay

    2016-09-01

    Full Text Available Legume seeds are important as protein and oil source for human diet. Understanding how their final seed size is determined is crucial to improve crop yield. In this study, we analyzed seed development of three accessions of the model legume, Medicago truncatula, displaying contrasted seed size. By comparing two large seed accessions to the reference accession A17, we described mechanisms associated with large seed size determination and potential factors modulating the final seed size. We observed that early events during embryogenesis had a major impact on final seed size and a delayed heart stage embryo development resulted to large seeds. We also observed that the difference in seed growth rate was mainly due to a difference in embryo cell number, implicating a role of cell division rate. Large seed accessions could be explained by an extended period of cell division due to a longer embryogenesis phase. According to our observations and recent reports, we observed that auxin (IAA and abscisic acid (ABA ratio could be a key determinant of cell division regulation at the end of embryogenesis. Overall, our study highlights that timing of events occurring during early seed development play decisive role for final seed size determination.

  6. REPLACEMENT IN RABBIT HERDS: A REVIEW

    Directory of Open Access Journals (Sweden)

    Ibrahim F.M. Marai

    2010-08-01

    Full Text Available Doe rabbit's replacement constitutes the annual renewal rate of new breeders that must be incorporated into the production stock. Criterion for culling non-productive animals differs significantly among fryer production colonies, foundation stocks and a colony with continuous enzootic disease or continuous malnourishment. In commercial rabbit production, good management improves the health and productivity of the entire herd, by reducing the all-time high replacement rates and improving economic viability. In the present article, a comprehensive review of numerous experiences in the rabbit production field of different countries, was presented. Basic recommendations for professional breeders were highlighted, covering critical issues such as the need for continuously upgrading the health status of the colony, the positive effect of   genetic selection and the nutritional conditioning and special treatment of young does being groomed as future replacements.

  7. Ecosystem size structure response to 21st century climate projection: large fish abundance decreases in the central North Pacific and increases in the California Current.

    Science.gov (United States)

    Woodworth-Jefcoats, Phoebe A; Polovina, Jeffrey J; Dunne, John P; Blanchard, Julia L

    2013-03-01

    Output from an earth system model is paired with a size-based food web model to investigate the effects of climate change on the abundance of large fish over the 21st century. The earth system model, forced by the Intergovernmental Panel on Climate Change (IPCC) Special report on emission scenario A2, combines a coupled climate model with a biogeochemical model including major nutrients, three phytoplankton functional groups, and zooplankton grazing. The size-based food web model includes linkages between two size-structured pelagic communities: primary producers and consumers. Our investigation focuses on seven sites in the North Pacific, each highlighting a specific aspect of projected climate change, and includes top-down ecosystem depletion through fishing. We project declines in large fish abundance ranging from 0 to 75.8% in the central North Pacific and increases of up to 43.0% in the California Current (CC) region over the 21st century in response to change in phytoplankton size structure and direct physiological effects. We find that fish abundance is especially sensitive to projected changes in large phytoplankton density and our model projects changes in the abundance of large fish being of the same order of magnitude as changes in the abundance of large phytoplankton. Thus, studies that address only climate-induced impacts to primary production without including changes to phytoplankton size structure may not adequately project ecosystem responses. © 2012 Blackwell Publishing Ltd.

  8. Spread of porcine circovirus associated disease (PCVAD in Ontario (Canada swine herds: Part I. Exploratory spatial analysis

    Directory of Open Access Journals (Sweden)

    Young Beth

    2010-12-01

    Full Text Available Abstract Background The systemic form of porcine circovirus associated disease (PCVAD, also known as postweaning multisystemic wasting syndrome (PMWS was initially detected in the early 1990s. Starting in 2004, the Canadian swine industry experienced considerable losses due to PCVAD, concurrent with a shift in genotype of porcine circovirus type 2 (PCV2. Objectives of the current study were to explore spatial characteristics of self-reported PCVAD distribution in Ontario between 2004 and 2008, and to investigate the existence and nature of local spread. Results The study included 278 swine herds from a large disease-monitoring project that included porcine reproductive and respiratory syndrome (PRRS virus-positive herds identified by the diagnostic laboratory, and PRRS virus-negative herds directly from the target population. Herds were included if they had growing pigs present on-site and available geographical coordinates for the sampling site. Furthermore, herds were defined as PCVAD-positive if a producer reported an outbreak of circovirus associated disease, or as PCVAD-negative if no outbreak was noted. Spatial trend was investigated using generalized additive models and time to PCVAD outbreak in a herd using Cox's proportional hazard model; spatial and spatio-temporal clustering was explored using K-functions; and location of most likely spatial and spatio-temporal clusters was investigated using scan statistics. Over the study period, the risk of reporting a PCVAD-positive herd tended to be higher in the eastern part of the province after adjustment for herd PRRS status (P = 0.05. This was partly confirmed for spread (Partial P P = 0.06 existence of spatio-temporal clustering of PCVAD and detection of a spatio-temporal cluster (P = 0.04. Conclusions In Ontario, PCVAD has shown a general trend, spreading from east-to-west. We interpret the existence of spatio-temporal clustering as evidence of spatio-temporal aggregation of PCVAD

  9. Challenging the myth of the irrational dairy farmer; understanding decision-making related to herd health.

    Science.gov (United States)

    Kristensen, E; Jakobsen, E B

    2011-01-01

    Veterinarians working with dairy cows are suggested to refocus their efforts from being task-oriented providers of single-cow therapy and develop themselves into advice-oriented herd health management advisors. The practising cattle veterinarian's ability to translate knowledge into on-farm application requires a profound understanding of the dairy farm as an integrated system. Consequently, educating and motivating farmers are key issues. To achieve such insight the veterinarian needs to work with several scientific disciplines, especially epidemiology and (behavioural) economics. This trans-disciplinary approach offers new methodological possibilities and challenges to students of dairy herd health management. Advisors working with dairy herd health management may sometimes experience that farmers do not follow their advice. Potentially, this could lead to the interpretation that such farmers are behaving irrationally. However, farmers who are confronted with advice suggesting a change of behaviour are placed in a state of cognitive dissonance. To solve such dissonance they may either comply with the advice or reduce the dissonance by convincing themselves that the suggested change in management is impossible to implement. Consequently, herd health management advisors must understand the fundamental and instrumental relationships between individual farmers' values, behaviour and perception of risk, to stimulate and qualify the farmer's decision-making in a way that will increase the farmer's satisfaction and subjective well-being. Traditionally, studies on herd health economics have focussed on financial methods to measure the value of technical outcomes from suggested changes in management, following the basic assumption that farmers strive to maximise profit. Farmers, however, may be motivated by very different activities, e.g. animal health and welfare or other farmers' recognition, making it impossible to provide 'one-size-fts-all' consultancy because the

  10. Finite-time and finite-size scalings in the evaluation of large-deviation functions: Numerical approach in continuous time.

    Science.gov (United States)

    Guevara Hidalgo, Esteban; Nemoto, Takahiro; Lecomte, Vivien

    2017-06-01

    Rare trajectories of stochastic systems are important to understand because of their potential impact. However, their properties are by definition difficult to sample directly. Population dynamics provides a numerical tool allowing their study, by means of simulating a large number of copies of the system, which are subjected to selection rules that favor the rare trajectories of interest. Such algorithms are plagued by finite simulation time and finite population size, effects that can render their use delicate. In this paper, we present a numerical approach which uses the finite-time and finite-size scalings of estimators of the large deviation functions associated to the distribution of rare trajectories. The method we propose allows one to extract the infinite-time and infinite-size limit of these estimators, which-as shown on the contact process-provides a significant improvement of the large deviation function estimators compared to the standard one.

  11. Finite-time and finite-size scalings in the evaluation of large-deviation functions: Numerical approach in continuous time

    Science.gov (United States)

    Guevara Hidalgo, Esteban; Nemoto, Takahiro; Lecomte, Vivien

    2017-06-01

    Rare trajectories of stochastic systems are important to understand because of their potential impact. However, their properties are by definition difficult to sample directly. Population dynamics provides a numerical tool allowing their study, by means of simulating a large number of copies of the system, which are subjected to selection rules that favor the rare trajectories of interest. Such algorithms are plagued by finite simulation time and finite population size, effects that can render their use delicate. In this paper, we present a numerical approach which uses the finite-time and finite-size scalings of estimators of the large deviation functions associated to the distribution of rare trajectories. The method we propose allows one to extract the infinite-time and infinite-size limit of these estimators, which—as shown on the contact process—provides a significant improvement of the large deviation function estimators compared to the standard one.

  12. Calf management practices and associations with herd-level morbidity and mortality on beef cow-calf operations.

    Science.gov (United States)

    Murray, C F; Fick, L J; Pajor, E A; Barkema, H W; Jelinski, M D; Windeyer, M C

    2016-03-01

    The objective of this study was to investigate calf management practices on beef cow-calf operations and determine associations with herd-level morbidity and mortality of pre-weaned calves. A 40-question survey about management practices, morbidity and mortality was administered to cow-calf producers by distributing paper surveys and by circulating an online link through various media. A total of 267 producers completed the survey. Data were analyzed with descriptive statistics and multivariable linear regression models. Average herd-level treatment risk for pre-weaning calf diarrhea (PCD) and bovine respiratory disease (BRD) were 4.9% and 3.0%, respectively. Average herd-level mortality within the first 24 h of life (stillbirth), from 1 to 7 days and 7 days to weaning were 2.3%, 1.1%, and 1.4%, respectively. Operations that never intervened at parturition had 4.7% higher PCD than those that occasionally did. On operations using small elastrator bands for castration, PCD was 1.9% higher than those using other methods. For every increase of 100 cows in herd size, BRD decreased by 1.1%. The association between BRD and PCD varied by when calving season began. Operations that used off-farm, frozen colostrum had a 1.1% increase in stillbirths. Operations that verified a calf had suckled had 0.7% lower mortality from 1 to 7 days of age. Those that intervened when colostrum was abnormal or that used small elastrator bands for castration had 1.9% and 1.4% higher mortality during the 1st week of life, respectively, compared with other operations. Mortality from 7 days to weaning was lower by 0.7% when calving season started in April compared with January or February and was higher by 1.0% for each additional week of calving season. Operations that intervened with colostrum consumption for assisted calvings had lower mortality from 7 days to weaning by 0.8% compared with those that did not. For every 1.0% increase in BRD, mortality from 7 days to weaning increased by 1

  13. Short communication: Factors affecting vitamin B12 concentration in milk of commercial dairy herds: An exploratory study.

    Science.gov (United States)

    Duplessis, M; Pellerin, D; Cue, R I; Girard, C L

    2016-06-01

    Only bacteria can synthesize vitamin B12, and this requires adequate Co supply. The natural source of vitamin B12 in human diets comes from animal products, especially those from ruminants. This study aimed to describe variability regarding vitamin B12 concentration in milk among and within commercial dairy herds in early lactation. A secondary objective was to explore potential causes for this variability such as genetic variation and diet characteristics. In total, 399 dairy cows (135 primiparous and 264 multiparous; 386 Holstein and 13 Jersey cows) in 15 commercial herds were involved. Milk samples were taken at 27.4±4.1 and 55.4±4.1d in milk. Neither parity (primiparous vs. multiparous) nor sampling time affected milk concentrations of vitamin B12. Nevertheless, vitamin B12 concentration in milk was highly variable among and within dairy herds. The lowest vitamin B12 concentration in milk of cows was observed in the Jersey herd. Among herds, vitamin B12 concentration in milk ranged from 2,309 to 3,878 pg/mL; one glass (250mL) of milk from those herds would provide between 23 and 40% of the vitamin B12 recommended daily allowance. Among individual cows, however, this provision varied between 16 and 57% of the recommendation. In spite of the limited size of the studied population, the heritability value was 0.23, suggesting that genetic selection could modify milk vitamin B12 concentration. We observed a positive relationship between milk vitamin B12 concentration and dietary acid detergent fiber content and a negative relationship between milk concentration of vitamin B12 and dietary crude protein content. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  14. Prevalence and herd-level risk factors for bovine tuberculosis in the State of Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Maria do Carmo Pessôa Silva

    2016-11-01

    Full Text Available Bovine tuberculosis is a zoonosis with worldwide distribution. Its control has a direct impact on public health and livestock production. This study estimated the prevalence of infected herds and adult bovines and evaluated risk factors associated with the presence of tuberculosis within herds in the state of Paraná. The state was divided in seven livestock regions and independent sampling was performed. A total of 1,419 farms were sampled and 16,045 animals were tested using the intradermal comparative cervical tuberculin diagnostic test. The apparent and estimated prevalence rates in farms and adult bovine animals were 2.15% (95% CI: 1.31-3.00 and 0.42% (95% CI: 0.04-0.81, respectively. It was not possible to state with 95% confidence that the disease prevalence in any region was significantly different from that in other regions. There were no positive animals in the western region, and the prevalence of positive herds and animals in the other regions ranged from 1.03% to 3.89% and 0.17% to 1.08%, respectively. The logistic regression model identified larger herd size (OR = 2.4 and mechanical cmilking (OR = 5.18 as risk factors associated with the presence of bovine tuberculosis. The combination of low prevalence with risk factors associated to larger herds and more intensive dairy farming, renders the state of Paraná a good candidate for the implementation of industry-based free-herd accreditation schemes and makes a case for planning risk-based surveillance targeted at major dairy basins.

  15. Effects of bovine necrotic vulvovaginitis on productivity in a dairy herd in Israel.

    Science.gov (United States)

    Blum, S; Mazuz, M; Brenner, J; Friedgut, O; Koren, O; Goshen, T; Elad, D

    2008-05-01

    Bovine necrotic vulvovaginitis (BNVV) is characterized by the development of a necrotic vulvovaginal lesion, almost exclusively in post-parturient first-lactation cows, associated with Porphyromonas levii. The scope of this survey was to evaluate the impact of BNVV on herd productivity as a means to rationally evaluate the resources that should be allocated in dealing with the syndrome. During an outbreak of BNVV in a dairy herd, following the introduction of a large number of cows from another farm, the impact of the animals' origin (local or transferred) and BNVV (positive or negative) upon involuntary culling rate, milk yield and days between pregnancies were assessed. The results indicated that the number of days between pregnancies was significantly higher in first-lactation cows with BNVV but was not influenced by the other independent variables. None of the other variables included in this survey had any effect on the involuntary culling rate and milk yield.

  16. A Long-Term Study of Neospora caninum Infection in a Swedish Dairy Herd

    Directory of Open Access Journals (Sweden)

    Uggla Arvid

    2003-06-01

    Full Text Available A longitudinal study was performed in a Swedish dairy herd where Neospora caninum had been isolated from a stillborn calf. Starting in autumn 1994, blood samples from all female animals in the herd were collected once yearly until 1999. The sera were analysed for presence of IgG1 antibodies to N. caninum by the iscom ELISA, and by an avidity ELISA to establish the timing of infection. In addition, data on reproductive performance were compiled. During the study the percentage of seropositive female animals increased from 63% to 87%. In 1994 a large number of young animals tested seropositive although their dams were seronegative, indicating that a transmission of the parasite other than the vertical had recently occurred. Low avidity values supported this assumption. The annual abortion rate increased from a mean of 2% before the initiation of the study to 9% in 1994–1998. During the same time, as judged by the avidity data, a large proportion of the animals shifted from being recently to being chronically infected. The source of the external infection in the herd could not be identified.

  17. HOW THE ROCKY FLATS ENVIRONMENTAL TECHNOLOGY SITE DEVELOPED A NEW WASTE PACKAGE USING A POLYUREA COATING THAT IS SAFELY AND ECONOMICALLY ELIMINATING SIZE REDUCTION OF LARGE ITEMS

    International Nuclear Information System (INIS)

    Dorr, Kent A.; Hogue, Richard S.; Kimokeo, Margaret K.

    2003-01-01

    One of the major challenges involved in closing the Rocky Flats Environmental Technology Site (RFETS) is the disposal of extremely large pieces of contaminated production equipment and building debris. Past practice has been to size reduce the equipment into pieces small enough to fit into approved, standard waste containers. Size reducing this equipment is extremely expensive, and exposes workers to high-risk tasks, including significant industrial, chemical, and radiological hazards. RFETS has developed a waste package using a Polyurea coating for shipping large contaminated objects. The cost and schedule savings have been significant

  18. Multivariate clustering of reindeer herding districts in Sweden according to range prerequisites for reindeer husbandry

    Directory of Open Access Journals (Sweden)

    Henrik Lundqvist

    2009-01-01

    Full Text Available The 51 reindeer herding districts in Sweden vary in productivity and prerequisites for reindeer herding. In this study we characterize and group reindeer herding districts based on relevant factors affecting reindeer productivity, i.e. topography, vegetation, forage value, habitat fragmentation and reachability, as well as season lengths, snow fall, ice-crust probability, and insect harassment, totally quantified in 15 variables. The herding districts were grouped into seven main groups and three single outliers through cluster analyses. The largest group, consisting of 14 herding districts, was further divided into four subgroups. The range properties of herding districts and groups of districts were characterized through principal component analyses. By comparisons of the suggested grouping of herding districts with existing administrative divisions, these appeared not to coincide. A new division of herding districts into six administrative sets of districts was suggested in order to improve administrative planning and management of the reindeer herding industry. The results also give possibilities for projections of alterations caused by an upcoming global climate change. Large scale investigations using geographical information systems (GIS and meteorological data would be helpful for administrative purposes, both nationally and internationally, as science-based decision tools in legislative, economical, ecological and structural assessments. Abstract in Swedish / Sammanfattning: Multivariat gruppering av svenska samebyar baserat på renbetesmarkernas grundförutsettningar Svenska renskötselområdet består av 51 samebyar som varierar i produktivitet och förutsättningar för renskötsel. Vi analyserade variationen mellan samebyar med avseende på 15 variabler som beskriver topografi, vegetation, betesvärde, fragmentering av betesmarker, klimat, skareförekomst och aktivitet av parasiterande insekter och vi föreslår en indelning av

  19. "Don't Have A Cow, Man!": Recognizing Herd Share Agreements for Raw Milk.

    Science.gov (United States)

    Mayer, Timothy J

    2015-01-01

    define “sale.” I argue that courts should consistently uphold properly written herd share agreements where such agreements are not prohibited because such agreements are deeply rooted in the longstanding practice of shared ownership agreements for livestock found throughout the agriculture industry. Furthermore, raw milk has been found by some researchers to be a low-risk food that may actually have some nutritional and even medicinal qualities not found in pasteurized milk. And to the extent that raw milk consumption could cause harm, the risk of a large-scale outbreak from milk obtained through a herd share is slight considering how few participants are in any given herd share.

  20. Factors associated with the growing-finishing performances of swine herds: an exploratory study on serological and herd level indicators.

    Science.gov (United States)

    Fablet, C; Rose, N; Grasland, B; Robert, N; Lewandowski, E; Gosselin, M

    2018-01-01

    Growing and finishing performances of pigs strongly influence farm efficiency and profitability. The performances of the pigs rely on the herd health status and also on several non-infectious factors. Many recommendations for the improvement of the technical performances of a herd are based on the results of studies assessing the effect of one or a limited number of infections or environmental factors. Few studies investigated jointly the influence of both type of factors on swine herd performances. This work aimed at identifying infectious and non-infectious factors associated with the growing and finishing performances of 41 French swine herds. Two groups of herds were identified using a clustering analysis: a cluster of 24 herds with the highest technical performance values (mean average daily gain = 781.1 g/day +/- 26.3; mean feed conversion ratio = 2.5 kg/kg +/- 0.1; mean mortality rate = 4.1% +/- 0.9; and mean carcass slaughter weight = 121.2 kg +/- 5.2) and a cluster of 17 herds with the lowest performance values (mean average daily gain =715.8 g/day +/- 26.5; mean feed conversion ratio = 2.6 kg/kg +/- 0.1; mean mortality rate = 6.8% +/- 2.0; and mean carcass slaughter weight = 117.7 kg +/- 3.6). Multiple correspondence analysis was used to identify factors associated with the level of technical performance. Infection with the porcine reproductive and respiratory syndrome virus and the porcine circovirus type 2 were infectious factors associated with the cluster having the lowest performance values. This cluster also featured farrow-to-finish type herds, a short interval between successive batches of pigs (≤3 weeks) and mixing of pigs from different batches in the growing or/and finishing steps. Inconsistency between nursery and fattening building management was another factor associated with the low-performance cluster. The odds of a herd showing low growing-finishing performance was significantly

  1. Group heterogeneity increases the risks of large group size: a longitudinal study of productivity in research groups.

    Science.gov (United States)

    Cummings, Jonathon N; Kiesler, Sara; Bosagh Zadeh, Reza; Balakrishnan, Aruna D

    2013-06-01

    Heterogeneous groups are valuable, but differences among members can weaken group identification. Weak group identification may be especially problematic in larger groups, which, in contrast with smaller groups, require more attention to motivating members and coordinating their tasks. We hypothesized that as groups increase in size, productivity would decrease with greater heterogeneity. We studied the longitudinal productivity of 549 research groups varying in disciplinary heterogeneity, institutional heterogeneity, and size. We examined their publication and citation productivity before their projects started and 5 to 9 years later. Larger groups were more productive than smaller groups, but their marginal productivity declined as their heterogeneity increased, either because their members belonged to more disciplines or to more institutions. These results provide evidence that group heterogeneity moderates the effects of group size, and they suggest that desirable diversity in groups may be better leveraged in smaller, more cohesive units.

  2. The underestimated role of temperature-oxygen relationship in large-scale studies on size-to-temperature response.

    Science.gov (United States)

    Walczyńska, Aleksandra; Sobczyk, Łukasz

    2017-09-01

    The observation that ectotherm size decreases with increasing temperature (temperature-size rule; TSR) has been widely supported. This phenomenon intrigues researchers because neither its adaptive role nor the conditions under which it is realized are well defined. In light of recent theoretical and empirical studies, oxygen availability is an important candidate for understanding the adaptive role behind TSR. However, this hypothesis is still undervalued in TSR studies at the geographical level. We reanalyzed previously published data about the TSR pattern in diatoms sampled from Icelandic geothermal streams, which concluded that diatoms were an exception to the TSR. Our goal was to incorporate oxygen as a factor in the analysis and to examine whether this approach would change the results. Specifically, we expected that the strength of size response to cold temperatures would be different than the strength of response to hot temperatures, where the oxygen limitation is strongest. By conducting a regression analysis for size response at the community level, we found that diatoms from cold, well-oxygenated streams showed no size-to-temperature response, those from intermediate temperature and oxygen conditions showed reverse TSR, and diatoms from warm, poorly oxygenated streams showed significant TSR. We also distinguished the roles of oxygen and nutrition in TSR. Oxygen is a driving factor, while nutrition is an important factor that should be controlled for. Our results show that if the geographical or global patterns of TSR are to be understood, oxygen should be included in the studies. This argument is important especially for predicting the size response of ectotherms facing climate warming.

  3. Earthquake resistance of cracked concrete embedded with large size rebars (D43 and D57) in nuclear containment

    Energy Technology Data Exchange (ETDEWEB)

    Kan, Y-C. [Chaoyang Univ. of Tech., Taichung, Taiwan (China); Pei, K-C. [Inst. of Nuclear Energy Research, Taiwan (China)

    2014-07-01

    The bond behavior of varying size re-bar (D19, D32, D43 and D57) embedded in concrete, under cyclic load in a pullout test, were investigated through a series of experiments and monitored in real-time by acoustic emission (AE) herein. Parallel tests of specimens with an existing crack were also conducted to observe the behavior of cracked concrete subject to cyclic load. The detailed acoustics information can be used for analyzing and comparing the effects of concrete with varying size re-bar. The results provide useful in formation in evaluating the safety of NPP RC structure subjected to cyclic load. (author)

  4. Quantification of population sizes of large herbivores and their long-term functional role in ecosystems using dung fungal spores

    NARCIS (Netherlands)

    Baker, Ambroise G.; Cornelissen, Perry; Bhagwat, Shonil A.; Vera, Frans M.W.; Willis, Katherine J.

    2016-01-01

    The relationship between large herbivore numbers and landscape cover over time is poorly understood. There are two schools of thought: one views large herbivores as relatively passive elements upon the landscape and the other as ecosystem engineers driving vegetation succession. The latter

  5. Population dynamics of the Kaminuriak caribou herd, 1968 - 1985

    Directory of Open Access Journals (Sweden)

    Douglas C. Heard

    1986-06-01

    Full Text Available The Kaminuraik caribou herd apparently declined from about 120 000 animals in 1950 to 63 000 in 1968. Beginning in 1968 documentation of herd trend was based on the estimate of the number of breeding (pregnant and post-partum females on the calving ground during the birth peak. It appeared as if we understood the basic population processes responsible for the decline when we correctly predicted a drop from 14 800 breeding females in 1977 to 13 000 in 1980. However a three-fold increase, to 41 000 breeding females in 1982, and continued growth thereafter, was unanticipated. Most of that increase must have resulted from an immigration of cows to the herd's traditional calving ground around Kaminuriak Lake, although increased birth rates, and increased survival rates also contributed to herd growth. Immigrant cows probably came from the northeastern mainland of the NWT

  6. Superficially porous particles with 1000Å pores for large biomolecule high performance liquid chromatography and polymer size exclusion chromatography.

    Science.gov (United States)

    Wagner, Brian M; Schuster, Stephanie A; Boyes, Barry E; Shields, Taylor J; Miles, William L; Haynes, Mark J; Moran, Robert E; Kirkland, Joseph J; Schure, Mark R

    2017-03-17

    To facilitate mass transport and column efficiency, solutes must have free access to particle pores to facilitate interactions with the stationary phase. To ensure this feature, particles should be used for HPLC separations which have pores sufficiently large to accommodate the solute without restricted diffusion. This paper describes the design and properties of superficially porous (also called Fused-Core ® , core shell or porous shell) particles with very large (1000Å) pores specifically developed for separating very large biomolecules and polymers. Separations of DNA fragments, monoclonal antibodies, large proteins and large polystyrene standards are used to illustrate the utility of these particles for efficient, high-resolution applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Bovine mastitis: prevalence, risk factors and isolation of Staphylococcus aureus in dairy herds at Hawassa milk shed, South Ethiopia.

    Science.gov (United States)

    Abebe, Rahmeto; Hatiya, Hagere; Abera, Mesele; Megersa, Bekele; Asmare, Kassahun

    2016-12-03

    Mastitis is a disease of major economic importance in dairy industry worldwide. It is of particular concern in developing countries like Ethiopia, where milk and milk products are scarce. The objectives of the study were to estimate the prevalence of mastitis, identify the cow-and herd-level potential risk factors and isolate Staphylococcus aureus, one of etiological agents for contagious mastitis, from cows positive for mastitis. A total of 529 lactating cows selected randomly from 95 herds were screened by California mastitis test (CMT) for sub-clinical mastitis. Also 172 milk samples collected from CMT positive cows were cultured for isolation of S. aureus. Based on CMT result and clinical examination, the prevalence of mastitis at herd-level was 74.7% (95% CI: 64.5, 82.8). The corresponding cow-level prevalence was 62.6% (95% CI: 58.3, 66.7), of which 59.2 and 3.4% were sub-clinical and clinical mastitis cases, respectively. S. aureus was isolated from 51.2% of the milk samples cultured and 73.2% of the herds affected with mastitis. In the multivariable logistic regression model, the herd-level factors significantly associated (p mastitis were herd size, bedding material, and milking mastitic cows last, while at cow-level, breed, parity, stage of lactation, udder and leg hygiene, and teat end shape were noted to have a significant effect on mastitis occurrence. The very high prevalence of mastitis, more importantly the sub-clinical one, in the herds examined revealed the huge potential economic loss the sector suffers. Perhaps this was attributed to lack of implementation of the routine mastitis prevention and control practices by all of the herd owners. The findings of this study warrants the need for strategic approach including dairy extension that focus on enhancing dairy farmers' awareness and practice of hygienic milking, regular screening for sub-clinical mastitis, dry cow therapy and culling of chronically infected cows.

  8. The evalution of reproduction parametres in chosen herd of sheep

    OpenAIRE

    BENEŠOVÁ, Kristýna

    2009-01-01

    It has been observed the breed herd of Texel sheep in the foothills area of Orlické mountains in the year 2005-2008. The base of herd was consisted of 374 ewes, 575 lambs and 6 rams in total. These parametres of reproduction - conception, fertility, rearing, empty ewes, abortions, lambing, stillborn, death after born, were monitored at ewes. For the parametres of reproduction at ewes were found significant effects of ewe´s age and ram´s line.

  9. Discrete hierarchical organization of social group sizes.

    Science.gov (United States)

    Zhou, W-X; Sornette, D; Hill, R A; Dunbar, R I M

    2005-02-22

    The 'social brain hypothesis' for the evolution of large brains in primates has led to evidence for the coevolution of neocortical size and social group sizes, suggesting that there is a cognitive constraint on group size that depends, in some way, on the volume of neural material available for processing and synthesizing information on social relationships. More recently, work on both human and non-human primates has suggested that social groups are often hierarchically structured. We combine data on human grouping patterns in a comprehensive and systematic study. Using fractal analysis, we identify, with high statistical confidence, a discrete hierarchy of group sizes with a preferred scaling ratio close to three: rather than a single or a continuous spectrum of group sizes, humans spontaneously form groups of preferred sizes organized in a geometrical series approximating 3-5, 9-15, 30-45, etc. Such discrete scale invariance could be related to that identified in signatures of herding behaviour in financial markets and might reflect a hierarchical processing of social nearness by human brains.

  10. Evaluation of Coxiella burnetii status in dairy cattle herds with bulk-tank milk positive by ELISA and PCR.

    Science.gov (United States)

    Piñero, A; Barandika, J F; Hurtado, A; García-Pérez, A L

    2014-04-01

    Bulk-tank milk (BTM) samples are frequently used to evaluate the health status of dairy livestock. A large-scale investigation carried out in BTM samples from dairy cattle herds from a Q fever-endemic region in Northern Spain revealed a high degree of exposure to Coxiella burnetii. This study was aimed at assessing the value of BTM samples analysis as an indicator of the C. burnetii status in dairy cattle herds. Three herds with BTM samples positive for C. burnetii by ELISA and PCR were selected, and blood, faeces and individual milk and BTM samples were analysed by serology and PCR. In spite of the high antibodies titres found in BTM samples, only one of the three farms presented an active infection by C. burnetii, as revealed by the presence of bacterial DNA in vaginal mucus and in environmental samples collected in the calving area, a seroprevalence around 40% in heifers and the seroconversion rate observed in cows. Results obtained indicated that the analysis of BTM samples is a good epidemiological tool at the population level that can be used to discriminate between seropositive and seronegative herds, but at the herd level, additional tests are necessary to evaluate whether Q fever is a potential problem in the farm. When Q fever is suspected in a cattle herd, sera from a small group of 1- to 3-year-old animals need to be analysed to investigate recent contact with C. burnetii. © 2012 Blackwell Verlag GmbH.

  11. Small genomes and large seeds: chromosome numbers, genome size and seed mass in diploid Aesculus species (Sapindaceae)

    Czech Academy of Sciences Publication Activity Database

    Krahulcová, Anna; Trávníček, Pavel; Krahulec, František; Rejmánek, M.

    2017-01-01

    Roč. 119, č. 6 (2017), s. 957-964 ISSN 0305-7364 Institutional support: RVO:67985939 Keywords : Aesculus * chromosome number * genome size * phylogeny * seed mass Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 4.041, year: 2016

  12. Population growth, movements, and status of the Nushagak Peninsula Caribou Herd following reintroduction, 1988 - 2000

    Directory of Open Access Journals (Sweden)

    Gail H. Collins

    2003-04-01

    Full Text Available Barren ground caribou (Rangifer tarandus were reintroduced to the Nushagak Peninsula, Alaska in February of 1988 after an absence of more than 100 years. Since reintroduction, herd growth and population dynamics have been monitored closely. At this time, there has been no significant dispersal from the herds' core range. The Nushagak Peninsula Caribou Herd (NPCH grew rapidly from 146 reintroduced individuals to over 1000 in 13 years. Dramatic mean annual growth during the first 6 years (1988-1994 of 38% (r = 0.32 can be attributed to the high percentage of females in the initial reintroduction, high calf production and survival, exceptional range conditions, few predators, and no hunting. However, the populations' exceptional growth (peak counts of 1400 slowed and stabilized between 1996¬1998 and then decreased between 1998 and 2000. Size, body condition and weights of calves captured in 2000 were significantly lower than those captured in 1995 and 1997. Although calf production also decreased from close to 100% (1990-1995 to about 91% (1996-2000, overall calf survival continued to be high. Legal harvest began in 1995, and harvest reports have accounted for approximately 3% of population mortality annually. Although brown bears (Ursus arctos and wolves (Canis lupus are present, the extent of predation is unknown. Mean home range of the NPCH was 674 km2 and group sizes were greatest during post-calving aggregation in July (mean = 127. Caribou population density on the Nushagak Peninsula reached approximately 1.2 caribou/km2 in 1997 before declining to about 1.0 caribou/km2. A range survey in 1994 noted only trace utilization of lichens on the Nushagak Peninsula by caribou. A subsequent survey in 1999 found moderate to severe utilization in 46% of plots, suggesting the reintroduced herd was beginning to alter range condition. Between 1997 and 2000, both calf production and condition of 10-month-old calves declined. Calving has also been delayed

  13. Autologous chondrocyte implantation: Is it likely to become a saviour of large-sized and full-thickness cartilage defect in young adult knee?

    Science.gov (United States)

    Zhang, Chi; Cai, You-Zhi; Lin, Xiang-Jin

    2016-05-01

    A literature review of the first-, second- and third-generation autologous chondrocyte implantation (ACI) technique for the treatment of large-sized (>4 cm(2)) and full-thickness knee cartilage defects in young adults was conducted, examining the current literature on features, clinical scores, complications, magnetic resonance image (MRI) and histological outcomes, rehabilitation and cost-effectiveness. A literature review was carried out in the main medical databases to evaluate the several studies concerning ACI treatment of large-sized and full-thickness knee cartilage defects in young adults. ACI technique has been shown to relieve symptoms and improve functional assessment in large-sized (>4 cm(2)) and full-thickness knee articular cartilage defect of young adults in short- and medium-term follow-up. Besides, low level of evidence demonstrated its efficiency and durability at long-term follow-up after implantation. Furthermore, MRI and histological evaluations provided the evidence that graft can return back to the previous nearly normal cartilage via ACI techniques. Clinical outcomes tend to be similar in different ACI techniques, but with simplified procedure, low complication rate and better graft quality in the third-generation ACI technique. ACI based on the experience of cell-based therapy, with the high potential to regenerate hyaline-like tissue, represents clinical development in treatment of large-sized and full-thickness knee cartilage defects. IV.

  14. Evidence from a Large Sample on the Effects of Group Size and Decision-Making Time on Performance in a Marketing Simulation Game

    Science.gov (United States)

    Treen, Emily; Atanasova, Christina; Pitt, Leyland; Johnson, Michael

    2016-01-01

    Marketing instructors using simulation games as a way of inducing some realism into a marketing course are faced with many dilemmas. Two important quandaries are the optimal size of groups and how much of the students' time should ideally be devoted to the game. Using evidence from a very large sample of teams playing a simulation game, the study…

  15. Success and failure of reindeer herding in Greenland

    Directory of Open Access Journals (Sweden)

    Christine Cuyler

    1999-04-01

    Full Text Available Animal husbandry is a recent innovation in Greenland, specifically reindeer husbandry is less than 50 years old. Reindeer husbandry was first established in mid-west Greenland and later in southern Greenland. The Greenland hunter tradition and culture is, however, still dominant in many communities. During the 1980s and 1990s, the incompatibility of these two traditions resulted in the failure of reindeer husbandry in mid-west Greenland. There were neither herding nor seasonal herd movements. Animals remained year round on the winter range, which was destroyed as lichens were trampled every summer. Without seasonal herd movements both sustainable range use and control of the herd were lost. Today, there are just two semi-domestic reindeer herds left, and both are in southern Greenland. One herd is commercially successful, and the other is under development. In mid-west Greenland, semi-domestic reindeer husbandry officially ended in 1998, and a hunt was initiated to remove the remaining population. Possibly, by the year 2000 any animals left in this region will be considered wild caribou.

  16. Markets, Herding and Response to External Information.

    Science.gov (United States)

    Carro, Adrián; Toral, Raúl; San Miguel, Maxi

    2015-01-01

    We focus on the influence of external sources of information upon financial markets. In particular, we develop a stochastic agent-based market model characterized by a certain herding behavior as well as allowing traders to be influenced by an external dynamic signal of information. This signal can be interpreted as a time-varying advertising, public perception or rumor, in favor or against one of two possible trading behaviors, thus breaking the symmetry of the system and acting as a continuously varying exogenous shock. As an illustration, we use a well-known German Indicator of Economic Sentiment as information input and compare our results with Germany's leading stock market index, the DAX, in order to calibrate some of the model parameters. We study the conditions for the ensemble of agents to more accurately follow the information input signal. The response of the system to the external information is maximal for an intermediate range of values of a market parameter, suggesting the existence of three different market regimes: amplification, precise assimilation and undervaluation of incoming information.

  17. Markets, Herding and Response to External Information.

    Directory of Open Access Journals (Sweden)

    Adrián Carro

    Full Text Available We focus on the influence of external sources of information upon financial markets. In particular, we develop a stochastic agent-based market model characterized by a certain herding behavior as well as allowing traders to be influenced by an external dynamic signal of information. This signal can be interpreted as a time-varying advertising, public perception or rumor, in favor or against one of two possible trading behaviors, thus breaking the symmetry of the system and acting as a continuously varying exogenous shock. As an illustration, we use a well-known German Indicator of Economic Sentiment as information input and compare our results with Germany's leading stock market index, the DAX, in order to calibrate some of the model parameters. We study the conditions for the ensemble of agents to more accurately follow the information input signal. The response of the system to the external information is maximal for an intermediate range of values of a market parameter, suggesting the existence of three different market regimes: amplification, precise assimilation and undervaluation of incoming information.

  18. Using animal performance data to evidence the under-reporting of case herds during an epizootic: application to an outbreak of bluetongue in cattle.

    Directory of Open Access Journals (Sweden)

    Simon Nusinovici

    Full Text Available Following the emergence of the Bluetongue virus serotype 8 (BTV-8 in France in 2006, a surveillance system (both passive and active was implemented to detect and follow precociously the progression of the epizootic wave. This system did not allow a precise estimation of the extent of the epizootic. Infection by BTV-8 is associated with a decrease of fertility. The objective of this study was to evaluate whether a decrease in fertility can be used to evidence the under-reporting of cases during an epizootic and to quantify to what extent non-reported cases contribute to the total burden of the epizootic. The cow fertility in herds in the outbreak area (reported or not was monitored around the date of clinical signs. A geostatistical interpolation method was used to estimate a date of clinical signs for non-reported herds. This interpolation was based on the spatiotemporal dynamic of confirmed case herds reported in 2007. Decreases in fertility were evidenced for both types of herds around the date of clinical signs. In non-reported herds, the decrease fertility was large (60% of the effect in reported herds, suggesting that some of these herds have been infected by the virus during 2007. Production losses in non-reported infected herds could thus contribute to an important part of the total burden of the epizootic. Overall, results indicate that performance data can be used to evidence the under-reporting during an epizootic. This approach could be generalized to pathogens that affect cattle's performance, including zoonotic agents such as Coxiella burnetii or Rift Valley fever virus.

  19. Effects of global warming on the biology and management of the Porcupine caribou herd

    International Nuclear Information System (INIS)

    Russell, D.E.

    1993-01-01

    The Porcupine caribou herd is a large migratory herd of Grant's caribou (Rangifer tarandus granti) that moves from winter ranges in taiga to calving and summering grounds north of the treeline in Alaska and the Northwest Territories. The migratory habits of the herd are described with reference to the major factors that govern the migration: spring snowmelt, summer insects, and winter snowfall. The effects of climate change (assuming a scenario involving a 2-4 week earlier period of snowmelt, a 2-4 degree C increase in summer temperature, and a 30-50% increase in winter snowfall) on caribou energetics are examined. Early snowmelt could have a potential benefit to caribou in early spring but could be detrimental by mid-June when energy and nutrient requirements are highest. Mosquito activity would increase, leading to a decrease in feeding time and an increased importance of insect relief areas in the mountains. Higher snowfall would also decrease feeding time and a tendency for the caribou to move to areas of low snow (Richardson Mountains and Ogilvie/Hart basins). An energetics model is applied to assess climate change effects on the weight change of productive adult female caribou. A 40% decline in parturition rate is predicted from the best-case to the worst-case (bad winter and high insect harassment). The impact of climate change on current wildlife management decisions is discussed. 13 refs., 3 figs., 1 tab

  20. Do sex, body size and reproductive condition influence the thermal preferences of a large lizard? A study in Tupinambis merianae.

    Science.gov (United States)

    Cecchetto, Nicolas Rodolfo; Naretto, Sergio

    2015-10-01

    Body temperature is a key factor in physiological processes, influencing lizard performances; and life history traits are expected to generate variability of thermal preferences in different individuals. Gender, body size and reproductive condition may impose specific requirements on preferred body temperatures. If these three factors have different physiological functions and thermal requirements, then the preferred temperature may represent a compromise that optimizes these physiological functions. Therefore, the body temperatures that lizards select in a controlled environment may reflect a temperature that maximizes their physiological needs. The tegu lizard Tupinambis merianae is one of the largest lizards in South America and has wide ontogenetic variation in body size and sexual dimorphism. In the present study we evaluate intraspecific variability of thermal preferences of T. merianae. We determined the selected body temperature and the rate at which males and females attain their selected temperature, in relation to body size and reproductive condition. We also compared the behavior in the thermal gradient between males and females and between reproductive condition of individuals. Our study show that T. merianae selected body temperature within a narrow range of temperatures variation in the laboratory thermal gradient, with 36.24±1.49°C being the preferred temperature. We observed no significant differences between sex, body size and reproductive condition in thermal preferences. Accordingly, we suggest that the evaluated categories of T. merianae have similar thermal requirements. Males showed higher rates to obtain heat than females and reproductive females, higher rates than non-reproductive ones females. Moreover, males and reproductive females showed a more dynamic behavior in the thermal gradient. Therefore, even though they achieve the same selected temperature, they do it differentially. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Refractory Inclusion Size Distribution and Fabric Measured in a Large Slab of the Allende CV3 Chondrite

    Science.gov (United States)

    Srinivasan, P.; Simon, Justin I.; Cuzzi, J. N.

    2013-01-01

    Aggregate textures of chondrites reflect accretion of early-formed particles in the solar nebula. Explanations for the size and density variations of particle populations found among chondrites are debated. Differences could have risen out of formation in different locations in the nebula, and/or they could have been caused by a sorting process [1]. Many ideas on the cause of chondrule sorting have been proposed; some including sorting by mass [2,3], by X-winds [4], turbulent concentration [5], and by photophoresis [6]. However, few similar studies have been conducted for Ca-, Al-rich inclusions (CAIs). These particles are known to have formed early, and their distribution could attest to the early stages of Solar System (ESS) history. Unfortunately, CAIs are not as common in chondrites as chondrules are, reducing the usefulness of studies restricted to a few thin sections. Furthermore, the largest sizes of CAIs are generally much larger than chondrules, and therefore rarely present in most studied chondrite thin sections. This study attempts to perform a more representative sampling of the CAI population in the Allende chondrite by investigating a two decimeter-sized slab.

  2. GENETIC CHANGES FOR PERFORMANCE TRAITS IN SLOVENIAN PIG NUCLEUS HERDS

    Directory of Open Access Journals (Sweden)

    Špela Malovrh

    2000-06-01

    Full Text Available In Slovenian pig nucleus herds, the genetic trends for performance traits in boars were investigated using mixed model methodology. Altogether, data sets from four farms with test stations consisted of 60709 records for five breeds: Swedish Landrace (SL, Large White (LW, Duroc (D, Pietrain (P, and German Landrace (GL boars from years 1975 to 1999. Separate analyses were performed for each farm using the PEST package. Breed, season, and weight on test within breed were fixed effects, while common litter environment and additive genetic effect were treated as random. Genetic trends for days on test from 30 to 100 kg (DoT30100, feed conversion efficiency from 30 to 100 kg (FCE30100, and ultrasonically measured backfat thickness (BF100 were expressed as linear regression of the averages of predicted breeding values on the year of birth. Estimates for genetic changes varied between farms and breeds from +0.0046 to –0.374 day, +0.0019 to – 0.013, and +0.262 to –0.221 mm per year for DoT30100, FCE30100, and BF100, respectively.

  3. A Large Size Chimeric Highly Immunogenic Peptide Presents Multistage Plasmodium Antigens as a Vaccine Candidate System against Malaria.

    Science.gov (United States)

    Lozano, José Manuel; Varela, Yahson; Silva, Yolanda; Ardila, Karen; Forero, Martha; Guasca, Laura; Guerrero, Yuly; Bermudez, Adriana; Alba, Patricia; Vanegas, Magnolia; Patarroyo, Manuel Elkin

    2017-11-01

    Rational strategies for obtaining malaria vaccine candidates should include not only a proper selection of target antigens for antibody stimulation, but also a versatile molecular design based on ordering the right pieces from the complex pathogen molecular puzzle towards more active and functional immunogens. Classical Plasmodium falciparum antigens regarded as vaccine candidates have been selected as model targets in this study. Among all possibilities we have chosen epitopes of Pf CSP, STARP; MSA1 and Pf 155/RESA from pre- and erythrocyte stages respectively for designing a large 82-residue chimeric immunogen. A number of options aimed at diminishing steric hindrance for synthetic procedures were assessed based on standard Fmoc chemistry such as building block orthogonal ligation; pseudo-proline and microwave-assisted procedures, therefore the large-chimeric target was produced, characterized and immunologically tested. Antigenicity and functional in vivo efficacy tests of the large-chimera formulations administered alone or as antigen mixtures have proven the stimulation of high antibody titers, showing strong correlation with protection and parasite clearance of vaccinated BALB/c mice after being lethally challenged with both P. berghei -ANKA and P. yoelii 17XL malaria strains. Besides, 3D structure features shown by the large-chimera encouraged as to propose using these rational designed large synthetic molecules as reliable vaccine candidate-presenting systems.

  4. A Large Size Chimeric Highly Immunogenic Peptide Presents Multistage Plasmodium Antigens as a Vaccine Candidate System against Malaria

    Directory of Open Access Journals (Sweden)

    José Manuel Lozano

    2017-11-01

    Full Text Available Rational strategies for obtaining malaria vaccine candidates should include not only a proper selection of target antigens for antibody stimulation, but also a versatile molecular design based on ordering the right pieces from the complex pathogen molecular puzzle towards more active and functional immunogens. Classical Plasmodium falciparum antigens regarded as vaccine candidates have been selected as model targets in this study. Among all possibilities we have chosen epitopes of PfCSP, STARP; MSA1 and Pf155/RESA from pre- and erythrocyte stages respectively for designing a large 82-residue chimeric immunogen. A number of options aimed at diminishing steric hindrance for synthetic procedures were assessed based on standard Fmoc chemistry such as building block orthogonal ligation; pseudo-proline and microwave-assisted procedures, therefore the large-chimeric target was produced, characterized and immunologically tested. Antigenicity and functional in vivo efficacy tests of the large-chimera formulations administered alone or as antigen mixtures have proven the stimulation of high antibody titers, showing strong correlation with protection and parasite clearance of vaccinated BALB/c mice after being lethally challenged with both P. berghei-ANKA and P. yoelii 17XL malaria strains. Besides, 3D structure features shown by the large-chimera encouraged as to propose using these rational designed large synthetic molecules as reliable vaccine candidate-presenting systems.

  5. A strain-, cow-, and herd-specific bio-economic simulation model of intramammary infections in dairy cattle herds.

    Science.gov (United States)

    Gussmann, Maya; Kirkeby, Carsten; Græsbøll, Kaare; Farre, Michael; Halasa, Tariq

    2018-07-14

    Intramammary infections (IMI) in dairy cattle lead to economic losses for farmers, both through reduced milk production and disease control measures. We present the first strain-, cow- and herd-specific bio-economic simulation model of intramammary infections in a dairy cattle herd. The model can be used to investigate the cost-effectiveness of different prevention and control strategies against IMI. The objective of this study was to describe a transmission framework, which simulates spread of IMI causing pathogens through different transmission modes. These include the traditional contagious and environmental spread and a new opportunistic transmission mode. In addition, the within-herd transmission dynamics of IMI causing pathogens were studied. Sensitivity analysis was conducted to investigate the influence of input parameters on model predictions. The results show that the model is able to represent various within-herd levels of IMI prevalence, depending on the simulated pathogens and their parameter settings. The parameters can be adjusted to include different combinations of IMI causing pathogens at different prevalence levels, representing herd-specific situations. The model is most sensitive to varying the transmission rate parameters and the strain-specific recovery rates from IMI. It can be used for investigating both short term operational and long term strategic decisions for the prevention and control of IMI in dairy cattle herds. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Modeling of the evolution of bubble size distribution of gas-liquid flow inside a large vertical pipe. Influence of bubble coalescence and breakup models

    International Nuclear Information System (INIS)

    Liao, Yixiang; Lucas, Dirk

    2011-01-01

    The range of gas-liquid flow applications in today's technology is immensely wide. Important examples can be found in chemical reactors, boiling and condensation equipments as well as nuclear reactors. In gas-liquid flows, the bubble size distribution plays an important role in the phase structure and interfacial exchange behaviors. It is therefore necessary to take into account the dynamic change of the bubble size distribution to get good predictions in CFD. An efficient 1D Multi-Bubble-Size-Class Test Solver was introduced in Lucas et al. (2001) for the simulation of the development of the flow structure along a vertical pipe. The model considers a large number of bubble classes. It solves the radial profiles of liquid and gas velocities, bubble-size class resolved gas fraction profiles as well as turbulence parameters on basis of the bubble size distribution present at the given axial position. The evolution of the flow along the height is assumed to be solely caused by the progress of bubble coalescence and break-up resulting in a bubble size distribution changing in the axial direction. In this model, the bubble coalescence and breakup models are very important for reasonable predictions of the bubble size distribution. Many bubble coalescence and breakup models have been proposed in the literature. However, some obvious discrepancies exist in the models; for example, the daughter bubble size distributions are greatly different from different bubble breakup models, as reviewed in our previous publication (Liao and Lucas, 2009a; 2010). Therefore, it is necessary to compare and evaluate typical bubble coalescence and breakup models that have been commonly used in the literature. Thus, this work is aimed to make a comparison of several typical bubble coalescence and breakup models and to discuss in detail the ability of the Test Solver to predict the evolution of bubble size distribution. (orig.)

  7. Sow-level risk factors for stillbirth of piglets in organic sow herds

    DEFF Research Database (Denmark)

    Rangstrup-Christensen, Lena; Krogh, Mogens Agerbo; Pedersen, Lene Juul

    2017-01-01

    In Danish organic pig production, one-third of total born piglets die before weaning, and stillbirth has previously crudely been estimated to account for 27% of the total preweaning mortality. The objective of this study was to evaluate season, litter size, parity and body condition of the sow...... as risk factors for stillbirth in nine commercial Danish organic pig herds. The study was conducted over a 1-year period, and the data included registrations on 5170 farrowings with 82 906 total born piglets. The average number of total born piglets per litter was 16.0, and the number of stillborn piglets...

  8. Does Decision Quality (Always) Increase with the Size of Information Samples? Some Vicissitudes in Applying the Law of Large Numbers

    Science.gov (United States)

    Fiedler, Klaus; Kareev, Yaakov

    2006-01-01

    Adaptive decision making requires that contingencies between decision options and their relative assets be assessed accurately and quickly. The present research addresses the challenging notion that contingencies may be more visible from small than from large samples of observations. An algorithmic account for such a seemingly paradoxical effect…

  9. Studies on the welding of heavy-section ASTM A542 Cl. 1 steel for large-sized pressure vessels

    International Nuclear Information System (INIS)

    Shimizu, Shigeki; Aota, Toshiichi; Kasahara, Masayuki

    1977-01-01

    ASTM A 542, Cl. 1 steel was developed and standardized recently, and is excellent in the high temperature strength and toughness as compared with conventionally used A 387, Grade 22 steel, accordingly the application to large pressure vessels is planned. This steel is a low alloy steel, and in case of large thickness, the possibility of cracking in the welded part is large. Also many times of annealing are required for the prevention of welding cracking, the relieving of residual stress, and the softening of hardened portion, but the possibility of cracking during stress-relieving annealing is large. In this study, Tekken type cracking test was carried out by coated electrode welding, and restricted cracking test was carried out by submerged arc welding of the A 542, Cl. 1 steel and A 387, Grade 22 steel, thus the welding cracking property was investigated, and the optimal welding conditions were selected. Also the test of cracking during the stress-relieving annealing of both steels was carried out, and the method of preventing the cracking was studied. The optimal conditions of stress-relieving annealing were selected, and the mechanism of the cracking was clarified. The mechanical properties of the joints welded and stress-relieved under the selected conditions were confirmed. (Kako, I.)

  10. Electrochemical machining of internal built-up surfaces of large-sized vessels for nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Ryabchenko, N N; Pulin, V Ya [Vsesoyuznyj Proektno-Tekhnologicheskij Inst. Atomnogo Mashinostroeniya i Kotlostroeniya, Rostov-na-Donu (USSR)

    1977-01-01

    Electrochemical machining (ECM) has been employed for finishing of mechanically processed inner surfaces of large lateral parts of construction bodies with welded 0Kh18N10T steel overlayer. The finishing technology developed reduces the surface roughness from 10 mcm to the standard 2.5 mcm at the efficiency of machining of 2-4 m/sup 2/ per hour.

  11. Structure and properties of large-sized forged disk of alloy type KhN73MBTYu-VD(EhI 698-VD)

    International Nuclear Information System (INIS)

    Sudakov, V.S.

    1994-01-01

    Investigation results are presented for structure and mechanical properties of serial large-sized forged disk 1100 mm in diameter produced of alloy type EhI 9698-VD hand tested after standard heat treatment and isothermal ageing at operating temperature. Chemical composition studies have revealed no macroheterogeneity. In a central cross-section macrostructure is free of pores, inclusions, delaminating and variation in grain size. The metal of the disk possesses high values of long-term rupture strength and creep resistance at 650-700 deg C

  12. Estimating the herd immunity effect of rotavirus vaccine.

    Science.gov (United States)

    Pollard, Suzanne L; Malpica-Llanos, Tanya; Friberg, Ingrid K; Fischer-Walker, Christa; Ashraf, Sania; Walker, Neff

    2015-07-31

    Diarrhea is one of the leading causes of death in children under 5, and an estimated 39% of these deaths are attributable to rotavirus. Currently two live, oral rotavirus vaccines have been introduced on the market; however, the herd immunity effect associated with rotavirus vaccine has not yet been quantified. The purpose of this meta-analysis was to estimate the herd immunity effects associated with rotavirus vaccines. We performed a systematic literature review of articles published between 2008 and 2014 that measured the impact of rotavirus vaccine on severe gastroenteritis (GE) morbidity or mortality. We assessed the quality of published studies using a standard protocol and conducted meta-analyses to estimate the herd immunity effect in children less than one year of age across all years presented in the studies. We conducted these analyses separately for studies reporting a rotavirus-specific GE outcome and those reporting an all-cause GE outcome. In studies reporting a rotavirus-specific GE outcome, four of five of which were conducted in the United States, the median herd effect across all study years was 22% [19-25%]. In studies reporting an all-cause GE outcome, all of which were conducted in Latin America, the median herd effect was 24.9% [11-30%]. There is evidence that rotavirus vaccination confers a herd immunity effect in children under one year of age in the United States and Latin American countries. Given the high variability in vaccine efficacy across regions, more studies are needed to better examine herd immunity effects in high mortality regions. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Comparison of Brachyspira hyodysenteriae Isolates Recovered from Pigs in Apparently Healthy Multiplier Herds with Isolates from Herds with Swine Dysentery.

    Directory of Open Access Journals (Sweden)

    Tom La

    Full Text Available Swine dysentery (SD is a mucohaemorrhagic colitis of grower/finisher pigs classically resulting from infection by the anaerobic intestinal spirochaete Brachyspira hyodysenteriae. This study aimed to determine whether B. hyodysenteriae isolates from pigs in three healthy German multiplier herds supplying gilts to other farms differed from isolates from nine German production herds with SD. Isolates were subjected to whole genomic sequencing, and in silico multilocus sequence typing showed that those from the three multiplier herds were of previously undescribed sequence types (ST132, ST133 and ST134, with all isolates from the same herd having the same ST. All isolates were examined for the presence of 332 genes encoding predicted virulence or virulence lifestyle associated factors, and these were well conserved. Isolates from one multiplier herd were atypical in being weakly haemolytic: they had 10 amino acid substitutions in the haemolysin III protein and five in the haemolysin activation protein compared to reference strain WA1, and had a disruption in the promoter site of the hlyA gene. These changes likely contribute to the weakly haemolytic phenotype and putative lack of virulence. These same isolates also had nine base pair insertions in the iron metabolism genes bitB and bitC and lacked five of six plasmid genes that previously have been associated with colonisation. Other overall differences between isolates from the different herds were in genes from three of five outer membrane proteins, which were not found in all the isolates, and in members of a block of six plasmid genes. Isolates from three herds with SD had all six plasmid genes, while isolates lacking some of these genes were found in the three healthy herds-but also in isolates from six herds with SD. Other differences in genes of unknown function or in gene expression may contribute to variation in virulence; alternatively, superior husbandry and better general health may have

  14. MANUFACTURING AND CONTINUOUS IMPROVEMENT PERFORMANCE LEVEL IN PLANTS OF MEXICO; A COMPARATIVE ANALYSIS AMONG LARGE AND MEDIUM SIZE PLANTS

    OpenAIRE

    Carlos Monge; Jesús Cruz

    2015-01-01

    A random and statistically significant sample of 40 medium (12) and large (28) manufacturing plants of Apodaca, Mexico were surveyed using a structured and validated questionnaire to investigate the level of implementation of lean manufacturing, sustainable manufacturing, continuous improvement and operational efficiency and environmental responsibility in them, it is important to mention it was found that performance in the mentioned philosophies, on the two categories of plants is low, howe...

  15. Fabrication of epoxy composites with large-pore sized mesoporous silica and investigation of their thermal expansion.

    Science.gov (United States)

    Suzuki, Norihiro; Kiba, Shosuke; Yamauchi, Yusuke

    2012-02-01

    We fabricate epoxy composites with low thermal expansion by using mesoporous silica particles with a large pore diameter (around 10 nm) as inorganic fillers. From a simple calculation, almost all the mesopores are estimated to be completely filled with the epoxy polymer. The coefficient of linear thermal expansion (CTE) values of the obtained epoxy composites proportionally decrease with the increase of the mesoporous silica content.

  16. 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.

  17. Detection and sizing of large-scale cracks in centrifugally cast stainless steel pipes using Lamb waves

    International Nuclear Information System (INIS)

    Ngoc, T.D.K.; Avioli, M.J. Jr.

    1988-01-01

    Application of conventional ultrasonic nondestructive evaluation (NDE) techniques to centrifugally cast stainless steel (CCSS) pipes in pressurized water reactors (PWRs) has been limited, mainly due to the anisotropy of the CCSS materials. Phenomena such as beam skewing and distortion are directly attributable to this anisotropy and cause severe difficulties in crack detection and sizing. To improve CCSS inspectability, the feasibility of using Lamb waves as the probing mechanism for detecting and characterizing a surface-breaking crack originating from the pipe interior surface is discussed. A similar research effort has been reported by Rokhlin who investigated the interaction of Lamb waves with delaminations in thin sheets. Rokhlin and Adler also reported recently on the use of Lamb waves for evaluating spot welds. The motivation for using this probing mechanism derives from the recognition that the difficulties introduced by beam skewing, beam distortion, and high attenuation are circumvented, since Lamb waves are not bulk waves, but are resonant vibrational modes of a solid plate

  18. Development of the quality control system of the readout electronics for the large size telescope of the Cherenkov Telescope Array observatory

    Science.gov (United States)

    Konno, Y.; Kubo, H.; Masuda, S.; Paoletti, R.; Poulios, S.; Rugliancich, A.; Saito, T.

    2016-07-01

    The Cherenkov Telescope Array (CTA) is the next generation VHE γ-ray observatory which will improve the currently available sensitivity by a factor of 10 in the range 100 GeV to 10 TeV. The array consists of different types of telescopes, called large size telescope (LST), medium size telescope (MST) and small size telescope (SST). A LST prototype is currently being built and will be installed at the Observatorio Roque de los Muchachos, island of La Palma, Canary islands, Spain. The readout system for the LST prototype has been designed and around 300 readout boards will be produced in the coming months. In this note we describe an automated quality control system able to measure basic performance parameters and quickly identify faulty boards.

  19. Bayesian inference of genetic parameters on litter size and gestation length in Hungarian Landrace and Hungarian Large White pigs

    Directory of Open Access Journals (Sweden)

    Zoltán Csörnyei

    2010-01-01

    Full Text Available Genetic parameters of number of piglets born alive (NBA and gestation length (GL were analyzed for 39798 Hungarian Landrace (HLA, 141397 records and 70356 Hungarian Large White (HLW, 246961 records sows. Bivariate repeatability animal models were used, applying a Bayesian statistics. Estimated and heritabilitie repeatabilities (within brackets, were low for NBA, 0.07 (0.14 for HLA and 0.08 (0.17 for HLW, but somewhat higher for GL, 0.18 (0.27 for HLA and 0.26 (0.35 for HLW. Estimated genetic correlations between NBA and GL were low, -0.08 for HLA and -0.05 for HLW.

  20. Dynamic correction of the laser beam coordinate in fabrication of large-sized diffractive elements for testing aspherical mirrors

    Science.gov (United States)

    Shimansky, R. V.; Poleshchuk, A. G.; Korolkov, V. P.; Cherkashin, V. V.

    2017-05-01

    This paper presents a method of improving the accuracy of a circular laser system in fabrication of large-diameter diffractive optical elements by means of a polar coordinate system and the results of their use. An algorithm for correcting positioning errors of a circular laser writing system developed at the Institute of Automation and Electrometry, SB RAS, is proposed and tested. Highprecision synthesized holograms fabricated by this method and the results of using these elements for testing the 6.5 m diameter aspheric mirror of the James Webb space telescope (JWST) are described..

  1. Herd-level interpretation of test results for epidemiologic studies of animal diseases

    DEFF Research Database (Denmark)

    Christensen, Jette; Gardner, Ian A.

    2000-01-01

    Correct classification of the true status of herds is an important component of epidemiologic studies and animal disease-control programs. We review theoretical aspects of herd-level testing through consideration of test performance (herd-level sensitivity, specificity and predictive values......), the factors affecting these estimates, and available software for calculations. We present new aspects and considerations concerning the effect of precision and bias in estimation of individual-test performance on herd-test performance and suggest methods (pooled testing, targeted sampling of subpopulations...... with higher prevalence, and use of combinations of tests) to improve herd-level sensitivity when the expected within-herd prevalence is low....

  2. Large breast size as a risk factor for late adverse effects of breast radiotherapy: Is residual dose inhomogeneity, despite 3D treatment planning and delivery, the main explanation?

    International Nuclear Information System (INIS)

    Goldsmith, Christy; Haviland, Joanne; Tsang, Yat; Sydenham, Mark; Yarnold, John

    2011-01-01

    Background and Purpose: Large breast size is associated with an increased risk of late adverse effects after breast conservation surgery and radiotherapy, even when 3D dosimetry is used. The purpose of this study is to test the hypothesis that residual dose inhomogeneity is sufficient to explain the association. Methods: Patients previously treated after breast conservation surgery with whole breast radiotherapy using 3D dosimetry and followed up in the UK FAST hypofractionation trial were selected for this analysis. The residual level of dose inhomogeneity across the whole breast treatment volume was used to test for association between residual dosimetry and post-treatment change in breast appearance at 2 years post-radiotherapy. Results: At 2 years, 201/279 (72%) of women had no change in photographic breast appearance, 61 (22%) had mild change and 17 (6%) had marked change. Breast size and dosimetry were both significantly associated with late effects in univariate analyses, but only breast size remained an independent significant risk factor for change in breast appearance when included in a multiple regression model together with other prognostic factors (p = 0.006 for trend). Conclusion: Large-breasted women are more likely to suffer change in breast size and shape after whole breast radiotherapy delivered using 3D dosimetry, but residual dose inhomogeneity is insufficient to explain the association.

  3. Courtship herding in the fiddler crab Uca elegans.

    Science.gov (United States)

    How, Martin J; Hemmi, Jan M

    2008-12-01

    Male and female animals are not always complicit during reproduction, giving rise to coercion. One example of a system that is assumed to involve sexual coercion is the mate herding behaviour of fiddler crabs: males push females towards the home burrow with the goal of forcing copulation at the burrow entrance. We recorded and analysed in detail the courtship behaviour of a North Australian species of fiddler crab Uca elegans. Courtship was composed of four main phases: broadcast waving, outward run, herding and at burrow display. During interactions males produced claw-waving displays which were directed posteriorly towards the female and which varied in timing and structure depending on the courtship phase. We suggest that courtship herding in U. elegans is driven primarily by mate choice for the following reasons, (1) females can evade herding, (2) no other reproductive strategies were observed, (3) males broadcast their presence and accompany courtship with conspicuous claw waves, and (4) the behaviour ends with the female leading the male into the home burrow. As an alternative function for herding in U. elegans we suggest that the behaviour represents a form of courtship guiding, in which males direct complicit females to the correct home burrow.

  4. Generalized herd effects and vaccine evaluation: impact of live influenza vaccine on off-target bacterial colonisation.

    Science.gov (United States)

    Mina, Michael J

    2017-06-01

    Interactions between pathogens and commensal microbes are major contributors to health and disease. Infectious diseases however are most often considered independent, viewed within a one-host one-pathogen paradigm and, by extension, the interventions used to treat and prevent them are measured and evaluated within this same paradigm. Vaccines, especially live vaccines, by stimulating immune responses or directly interacting with other microbes can alter the environment in which they act, with effects that span across pathogen species. Live attenuated infl uenza vaccines for example, while safe, increase upper respiratory tract bacterial carriage density of important human commensal pathogens like Streptococcus pneumoniae and Staphylococcus aureus. Further, by altering the ecological niche and dynamics of phylogenetically distinct microbes within the host, vaccines may unintentionally affect transmission of non-vaccine targeted pathogens. Thus, vaccine effects may span across species and across scales, from the individual to the population level. In keeping with traditional vaccine herd-effects that indirectly protect even unvaccinated individuals by reducing population prevalence of vaccine-targeted pathogens, we call these cross-species cross-scale effects "generalized herd-effects". As opposed to traditional herd-effects, "generalized" relaxes the assumption that the effect occurs at the level of the vaccine-target pathogen and "herd effect" implies, as usual, that the effects indirectly impact the population at large, including unvaccinated bystanders. Unlike traditional herd-effects that decrease population prevalence of the vaccine-target, generalized herd-effects may decrease or increase prevalence and disease by the off-target pathogen. LAIV, for example, by increasing pneumococcal density in the upper respiratory tract of vaccine recipients, especially children, may increase pneumococcal transmission and prevalence, leading to excess pneumococcal invasive

  5. Technology of CCS coal utilization (outline of large-size demonstration test for CCS); CCS tan riyo gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Konno, K [Center for Coal Utilization, Japan, Tokyo (Japan); Hironaka, H [Idemitsu Kosan Co. Ltd., Tokyo (Japan)

    1996-09-01

    The coal cartridge system (CCS) is a series of the total system, in which coal is processed centrally at a supply base for each unit of consumer areas, supplied as pulverized coal in bulk units, and coal ash after combustion is recovered and treated. The system is expected of advantages resulted from the centralized production, elimination of handling troubles, and cleanliness. Following a small scale demonstration test, a large demonstration test for practically usable scale has begun in 1990, and completed in fiscal 1995. This paper introduces the CCS and reports the result of the test. In the large demonstration test, a supply station (with manufacturing capability of 200,000 tons a year) was installed in the Aichi refinery of Idemitsu Kosan Co., Ltd., and systematization on quality design and system technologies has been carried out. Long-term continuous operation for five years was achieved (operation time of the supply facilities was about 19,000 hours) without a failure and accident, to which every elemental technology was evaluated highly, and convenience and reliability of the system was verified. 13 figs., 3 tabs.

  6. Structural evolution of Ti destroyable interlayer in large-size diamond film deposition by DC arc plasma jet

    Science.gov (United States)

    Guo, Jianchao; Li, Chengming; Liu, Jinlong; Wei, Junjun; Chen, Liangxian; Hua, Chenyi; Yan, Xiongbo

    2016-05-01

    The addition of titanium (Ti) interlayer was verified to reduce the residual stress of diamond films by self-fracturing and facilitate the harvest of a crack-free free-standing diamond film prepared by direct current (DC) arc plasma jet. In this study, the evolution of the Ti interlayer between large-area diamond film and substrate was studied and modeled in detail. The evolution of the interlayer was found to be relevant to the distribution of the DC arc plasma, which can be divided into three areas (arc center, arc main, and arc edge). The formation rate of titanium carbide (TiC) in the arc main was faster than in the other two areas and resulted in the preferred generation of crack in the diamond film in the arc main during cooling. Sandwich structures were formed along with the growth of TiC until the complete transformation of the Ti interlayer. The interlayer released stress via self-fracture. Avoiding uneven fragile regions that formed locally in the interlayer and achieving cooperatively released stress are crucial for the preparation of large crack-free diamond films.

  7. Herd-Level Mastitis-Associated Costs on Canadian Dairy Farms

    Directory of Open Access Journals (Sweden)

    Mahjoob Aghamohammadi

    2018-05-01

    Full Text Available Mastitis imposes considerable and recurring economic losses on the dairy industry worldwide. The main objective of this study was to estimate herd-level costs incurred by expenditures and production losses associated with mastitis on Canadian dairy farms in 2015, based on producer reports. Previously, published mastitis economic frameworks were used to develop an economic model with the most important cost components. Components investigated were divided between clinical mastitis (CM, subclinical mastitis (SCM, and other costs components (i.e., preventive measures and product quality. A questionnaire was mailed to 374 dairy producers randomly selected from the (Canadian National Dairy Study 2015 to collect data on these costs components, and 145 dairy producers returned a completed questionnaire. For each herd, costs due to the different mastitis-related components were computed by applying the values reported by the dairy producer to the developed economic model. Then, for each herd, a proportion of the costs attributable to a specific component was computed by dividing absolute costs for this component by total herd mastitis-related costs. Median self-reported CM incidence was 19 cases/100 cow-year and mean self-reported bulk milk somatic cell count was 184,000 cells/mL. Most producers reported using post-milking teat disinfection (97% and dry cow therapy (93%, and a substantial proportion of producers reported using pre-milking teat disinfection (79% and wearing gloves during milking (77%. Mastitis costs were substantial (662 CAD per milking cow per year for a typical Canadian dairy farm, with a large portion of the costs (48% being attributed to SCM, and 34 and 15% due to CM and implementation of preventive measures, respectively. For SCM, the two most important cost components were the subsequent milk yield reduction and culling (72 and 25% of SCM costs, respectively. For CM, first, second, and third most important cost components were

  8. Herd-Level Mastitis-Associated Costs on Canadian Dairy Farms

    Science.gov (United States)

    Aghamohammadi, Mahjoob; Haine, Denis; Kelton, David F.; Barkema, Herman W.; Hogeveen, Henk; Keefe, Gregory P.; Dufour, Simon

    2018-01-01

    Mastitis imposes considerable and recurring economic losses on the dairy industry worldwide. The main objective of this study was to estimate herd-level costs incurred by expenditures and production losses associated with mastitis on Canadian dairy farms in 2015, based on producer reports. Previously, published mastitis economic frameworks were used to develop an economic model with the most important cost components. Components investigated were divided between clinical mastitis (CM), subclinical mastitis (SCM), and other costs components (i.e., preventive measures and product quality). A questionnaire was mailed to 374 dairy producers randomly selected from the (Canadian National Dairy Study 2015) to collect data on these costs components, and 145 dairy producers returned a completed questionnaire. For each herd, costs due to the different mastitis-related components were computed by applying the values reported by the dairy producer to the developed economic model. Then, for each herd, a proportion of the costs attributable to a specific component was computed by dividing absolute costs for this component by total herd mastitis-related costs. Median self-reported CM incidence was 19 cases/100 cow-year and mean self-reported bulk milk somatic cell count was 184,000 cells/mL. Most producers reported using post-milking teat disinfection (97%) and dry cow therapy (93%), and a substantial proportion of producers reported using pre-milking teat disinfection (79%) and wearing gloves during milking (77%). Mastitis costs were substantial (662 CAD per milking cow per year for a typical Canadian dairy farm), with a large portion of the costs (48%) being attributed to SCM, and 34 and 15% due to CM and implementation of preventive measures, respectively. For SCM, the two most important cost components were the subsequent milk yield reduction and culling (72 and 25% of SCM costs, respectively). For CM, first, second, and third most important cost components were culling (48

  9. γ-Fe{sub 2}O{sub 3} by sol–gel with large nanoparticles size for magnetic hyperthermia application

    Energy Technology Data Exchange (ETDEWEB)

    Lemine, O.M., E-mail: leminej@yahoo.com [Physics Department, College of Sciences, Al Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh (Saudi Arabia); Omri, K. [Laboratory of Physics of Materials and Nanomaterials Applied at Environment (LaPhyMNE), Faculty of Sciences in Gabes, Gabes (Tunisia); Iglesias, M.; Velasco, V. [Instituto de Magnetismo Aplicado, UCM-ADIF-CSIC (Spain); Crespo, P.; Presa, P. de la [Instituto de Magnetismo Aplicado, UCM-ADIF-CSIC (Spain); Dpto. Física de Materiales, Universidad Complutense de Madrid (Spain); El Mir, L. [Physics Department, College of Sciences, Al Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh (Saudi Arabia); Laboratory of Physics of Materials and Nanomaterials Applied at Environment (LaPhyMNE), Faculty of Sciences in Gabes, Gabes (Tunisia); Bouzid, Houcine [Promising Centre for Sensors and Electronic Devices (PCSED), Najran University, P.O. Box 1988, Najran 11001 (Saudi Arabia); Laboratoire des Matériaux Ferroélectriques, Faculté des Sciences de Sfax, Route Soukra Km 3 5, B.P. 802, F-3018 Sfax (Tunisia); Yousif, A. [Department of Physics, College of Science, Sultan Qaboos University, P.O. Box 36, Code 123, Al Khoud (Oman); Al-Hajry, Ali [Promising Centre for Sensors and Electronic Devices (PCSED), Najran University, P.O. Box 1988, Najran 11001 (Saudi Arabia)

    2014-09-01

    Highlights: • Iron oxides nanoparticles with different sizes are successfully synthesized using sol–gel method. • The obtained nanoparticles are mainly composed of maghemite phase (γ-Fe{sub 2}O{sub 3}). • A non-negligible coercive field suggests that the particles are ferromagnetic. • A mean heating efficiency of 30 W/g is obtained for the smallest particles at 110 kHz and 190 Oe. - Abstract: Iron oxides nanoparticles with different sizes are successfully synthesized using sol–gel method. X-ray diffraction (XRD) and Mössbauer spectroscopy show that the obtained nanoparticles are mainly composed of maghemite phase (γ-Fe{sub 2}O{sub 3}). XRD and transmission electron microscopy (TEM) results suggest that the nanoparticles have sizes ranging from 14 to 30 nm, which are indeed confirmed by large magnetic saturation and high blocking temperature. At room temperature, the observation of a non-negligible coercive field suggests that the particles are ferro/ferrimagnetic. The specific absorption rate (SAR) under an alternating magnetic field is investigated as a function of size, frequency and amplitude of the applied magnetic field. A mean heating efficiency of 30 W/g is obtained for the smallest particles at 110 kHz and 190 Oe, whereas further increase of particle size does not improve significantly the heating efficiency.

  10. Signal Formation Processes in Micromegas Detectors and Quality Control for large size Detector Construction for the ATLAS New Small Wheel

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00387450; Rembser, Christoph

    2017-08-04

    The Micromegas technology is one of the most successful modern gaseous detector concepts and widely utilized in nuclear and particle physics experiments. Twenty years of R & D rendered the technology sufficiently mature to be selected as precision tracking detector for the New Small Wheel (NSW) upgrade of the ATLAS Muon spectrometer. This will be the first large scale application of Micromegas in one of the major LHC experiments. However, many of the fundamental microscopic processes in these gaseous detectors are still not fully understood and studies on several detector aspects, like the micromesh geometry, have never been addressed systematically. The studies on signal formation in Micromegas, presented in the first part of this thesis, focuses on the microscopic signal electron loss mechanisms and the amplification processes in electron gas interaction. Based on a detailed model of detector parameter dependencies, these processes are scrutinized in an iterating comparison between exper- imental result...

  11. Herd factors associated with dairy cow mortality.

    Science.gov (United States)

    McConnel, C; Lombard, J; Wagner, B; Kopral, C; Garry, F

    2015-08-01

    Summary studies of dairy cow removal indicate increasing levels of mortality over the past several decades. This poses a serious problem for the US dairy industry. The objective of this project was to evaluate associations between facilities, herd management practices, disease occurrence and death rates on US dairy operations through an analysis of the National Animal Health Monitoring System's Dairy 2007 survey. The survey included farms in 17 states that represented 79.5% of US dairy operations and 82.5% of the US dairy cow population. During the first phase of the study operations were randomly selected from a sampling list maintained by the National Agricultural Statistics Service. Only farms that participated in phase I and had 30 or more dairy cows were eligible to participate in phase II. In total, 459 farms had complete data for all selected variables and were included in this analysis. Univariable associations between dairy cow mortality and 162 a priori identified operation-level management practices or characteristics were evaluated. Sixty of the 162 management factors explored in the univariate analysis met initial screening criteria and were further evaluated in a multivariable model exploring more complex relationships. The final weighted, negative binomial regression model included six variables. Based on the incidence rate ratio, this model predicted 32.0% less mortality for operations that vaccinated heifers for at least one of the following: bovine viral diarrhea, infectious bovine rhinotracheitis, parainfluenza 3, bovine respiratory syncytial virus, Haemophilus somnus, leptospirosis, Salmonella, Escherichia coli or clostridia. The final multivariable model also predicted a 27.0% increase in mortality for operations from which a bulk tank milk sample tested ELISA positive for bovine leukosis virus. Additionally, an 18.0% higher mortality was predicted for operations that used necropsies to determine the cause of death for some proportion of dead

  12. Genome wide analysis of drug-induced torsades de pointes: lack of common variants with large effect sizes.

    Directory of Open Access Journals (Sweden)

    Elijah R Behr

    Full Text Available Marked prolongation of the QT interval on the electrocardiogram associated with the polymorphic ventricular tachycardia Torsades de Pointes is a serious adverse event during treatment with antiarrhythmic drugs and other culprit medications, and is a common cause for drug relabeling and withdrawal. Although clinical risk factors have been identified, the syndrome remains unpredictable in an individual patient. Here we used genome-wide association analysis to search for common predisposing genetic variants. Cases of drug-induced Torsades de Pointes (diTdP, treatment tolerant controls, and general population controls were ascertained across multiple sites using common definitions, and genotyped on the Illumina 610k or 1M-Duo BeadChips. Principal Components Analysis was used to select 216 Northwestern European diTdP cases and 771 ancestry-matched controls, including treatment-tolerant and general population subjects. With these sample sizes, there is 80% power to detect a variant at genome-wide significance with minor allele frequency of 10% and conferring an odds ratio of ≥2.7. Tests of association were carried out for each single nucleotide polymorphism (SNP by logistic regression adjusting for gender and population structure. No SNP reached genome wide-significance; the variant with the lowest P value was rs2276314, a non-synonymous coding variant in C18orf21 (p  =  3×10(-7, odds ratio = 2, 95% confidence intervals: 1.5-2.6. The haplotype formed by rs2276314 and a second SNP, rs767531, was significantly more frequent in controls than cases (p  =  3×10(-9. Expanding the number of controls and a gene-based analysis did not yield significant associations. This study argues that common genomic variants do not contribute importantly to risk for drug-induced Torsades de Pointes across multiple drugs.

  13. Herd-level risk factors for lameness in freestall farms in the northeastern United States and California.

    Science.gov (United States)

    Chapinal, N; Barrientos, A K; von Keyserlingk, M A G; Galo, E; Weary, D M

    2013-01-01

    The objective was to investigate the association between herd-level management and facility design factors and the prevalence of lameness in high-producing dairy cows in freestall herds in the northeastern United States (NE; Vermont, New York, Pennsylvania) and California (CA). Housing and management measures such as pen space, stall design, bedding type, and milking routine were collected for the high-pro