Influence of group size on the success of wolves hunting bison.

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Daniel R MacNulty

Full Text Available An intriguing aspect of social foraging behaviour is that large groups are often no better at capturing prey than are small groups, a pattern that has been attributed to diminished cooperation (i.e., free riding in large groups. Although this suggests the formation of large groups is unrelated to prey capture, little is known about cooperation in large groups that hunt hard-to-catch prey. Here, we used direct observations of Yellowstone wolves (Canis lupus hunting their most formidable prey, bison (Bison bison, to test the hypothesis that large groups are more cooperative when hunting difficult prey. We quantified the relationship between capture success and wolf group size, and compared it to previously reported results for Yellowstone wolves hunting elk (Cervus elaphus, a prey that was, on average, 3 times easier to capture than bison. Whereas improvement in elk capture success levelled off at 2-6 wolves, bison capture success levelled off at 9-13 wolves with evidence that it continued to increase beyond 13 wolves. These results are consistent with the hypothesis that hunters in large groups are more cooperative when hunting more formidable prey. Improved ability to capture formidable prey could therefore promote the formation and maintenance of large predator groups, particularly among predators that specialize on such prey.

Human Activity Dampens the Benefits of Group Size on Vigilance in Khulan (Equus hemionus in Western China.

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Mu-Yang Wang

Full Text Available Animals receive anti-predator benefits from social behavior. As part of a group, individuals spend less time being vigilant, and vigilance decreases with increasing group size. This phenomenon, called "the many-eyes effect", together with the "encounter dilution effect", is considered among the most important factors determining individual vigilance behavior. However, in addition to group size, other social and environmental factors also influence the degree of vigilance, including disturbance from human activities. In our study, we examined vigilance behavior of Khulans (Equus hemionus in the Xinjiang Province in western China to test whether and how human disturbance and group size affect vigilance. According to our results, Khulan showed a negative correlation between group size and the percentage time spent vigilant, although this negative correlation depended on the groups' disturbance level. Khulan in the more disturbed area had a dampened benefit from increases in group size, compared to those in the undisturbed core areas. Provision of continuous areas of high-quality habitat for Khulans will allow them to form larger undisturbed aggregations and to gain foraging benefits through reduced individual vigilance, as well as anti-predator benefits through increased probability of predator detection.

Human Activity Dampens the Benefits of Group Size on Vigilance in Khulan (Equus hemionus) in Western China.

Science.gov (United States)

Wang, Mu-Yang; Ruckstuhl, Kathreen E; Xu, Wen-Xuan; Blank, David; Yang, Wei-Kang

2016-01-01

Animals receive anti-predator benefits from social behavior. As part of a group, individuals spend less time being vigilant, and vigilance decreases with increasing group size. This phenomenon, called "the many-eyes effect", together with the "encounter dilution effect", is considered among the most important factors determining individual vigilance behavior. However, in addition to group size, other social and environmental factors also influence the degree of vigilance, including disturbance from human activities. In our study, we examined vigilance behavior of Khulans (Equus hemionus) in the Xinjiang Province in western China to test whether and how human disturbance and group size affect vigilance. According to our results, Khulan showed a negative correlation between group size and the percentage time spent vigilant, although this negative correlation depended on the groups' disturbance level. Khulan in the more disturbed area had a dampened benefit from increases in group size, compared to those in the undisturbed core areas. Provision of continuous areas of high-quality habitat for Khulans will allow them to form larger undisturbed aggregations and to gain foraging benefits through reduced individual vigilance, as well as anti-predator benefits through increased probability of predator detection.

Chromosome sizes of phytoplasmas composing major phylogenetic groups and subgroups.

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Marcone, C; Neimark, H; Ragozzino, A; Lauer, U; Seemüller, E

1999-09-01

ABSTRACT Chromosome sizes of 71 phytoplasmas belonging to 12 major phylogenetic groups including several of the aster yellows subgroups were estimated from electrophoretic mobilities of full-length chromosomes in pulsed-field gels. Considerable variation in genome size, from 660 to 1,130 kilobases (kb), was observed among aster yellows phytoplasmas. Chromosome size heterogeneity was also observed in the stolbur phytoplasma group (range 860 to 1,350 kb); in this group, isolate STOLF contains the largest chromosome found in a phytoplasma to date. A wide range of chromosome sizes, from 670 to 1,075 kb, was also identified in the X-disease group. The other phytoplasmas examined, which included members of the apple proliferation, Italian alfalfa witches' broom, faba bean phyllody, pigeon pea witches' broom, sugarcane white leaf, Bermuda grass white leaf, ash yellows, clover proliferation, and elm yellows groups, all have chromosomes smaller than 1 megabase, and the size ranges within each of these groups is narrower than in the aster yellows, stolbur, and X-disease groups. The smallest chromosome, approximately 530 kb, was found in two Bermuda grass white leaf phytoplasma isolates. This not only is the smallest mollicute chromosome found to date, but also is the smallest chromosome known for any cell. More than one large DNA band was observed in several phytoplasma preparations. Possible explanations for the occurrence of more than one band may be infection of the host plant by different phytoplasmas, the presence of more than one chromosome in the same organism, or the presence of large extrachromosomal DNA elements.

Size of government and entrepreneurship. Analysis of three groups of countries with different economic development

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Juan Carlos Díaz Casero

2015-07-01

Full Text Available This study analyzes the impact of the "size of government" in entrepreneurial activity for countries with different levels of economical development. It has been used the variables "size of government" of the economic freedom indices released by the Economic Freedom Network (2000-2009 and by The Heritage Foundation (2000-2011, and the variables of "entrepreneurship" released by the Global Entrepreneurship Monitor. Furthermore, the same analysis has been carried out grouping the countries by development level, following the classification elaborated by the World Economic Forum. Statistical analyses of correlations have shown that the “size of government” is related to entrepreneurship. The variables "Size of Government: Expenditures, Taxes and Enterprises" and " Government Size” have revealed a positive correlation with the total, opportunity and necessity entrepreneurial activity indices for the economies based on efficiency and innovation, thus less taxes on income and lower government spending, increase the entrepreneurship of the country. In “factor driven economies”, there is no relationship between the size of government and entrepreneurship

Influence of social mixing and group size on skin lesions and mounting in organic entire male pigs

DEFF Research Database (Denmark)

Thomsen, Rikke; Edwards, Sandra A; Rousing, Tine

2016-01-01

in management procedures and production system might be needed. Elements from the organic pig production system might be beneficial in this aspect. The aim of this article is to investigate the effect of grouping strategy including social mixing and group size on levels of mounting behaviour and skin lesions...... at weaning. A second mixing occurred at insertion to fattening pens for pigs being regrouped. Counting of skin lesions (1348 or 1124 pigs) and registration of mounting behaviour (1434 or 1258 pigs) were done on two occasions during the experimental period. No interactive effects were found between social...... mixing and group size on either skin lesions or mounting frequency. Herd differences were found for both mounting frequency and number of skin lesions. No association between skin lesions and mounting were revealed. Social mixing and group size were shown as interacting effects with herds on mounting...

Are range-size distributions consistent with species-level heritability?

DEFF Research Database (Denmark)

Borregaard, Michael Krabbe; Gotelli, Nicholas; Rahbek, Carsten

2012-01-01

The concept of species-level heritability is widely contested. Because it is most likely to apply to emergent, species-level traits, one of the central discussions has focused on the potential heritability of geographic range size. However, a central argument against range-size heritability has...... been that it is not compatible with the observed shape of present-day species range-size distributions (SRDs), a claim that has never been tested. To assess this claim, we used forward simulation of range-size evolution in clades with varying degrees of range-size heritability, and compared the output...

Correlation of the size of undescended testis with its location in various age groups

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Taqvi, S R.H.; Akhtar, J; Batool, T; Farhat, M [National Inst. of child Health, Karachi (Pakistan). Dept. of Peadiatrics; Tabassum, R [National Inst. of Child Health, Karachi (Pakistan). Dept. of Radiology

2006-09-15

To assess the correlation of the size of undescended testis with its location in children of various age groups, per- operatively. Children presenting with undescended testis at surgical outpatient were recruited. Physical examination and relevant investigations (haemoglobin, ultrasound for location and size of testes) were performed. Patients were divided randomly into three age groups, group I (8 months - 2.5 years), group II (2.6 - 8 years), group III (8.1-13 years). At orchiopexy location and size of undescended testis were noted. Patients were further sub-divided into groups according to peroperative location of undescended testis, group A (intra-abdominal), group B (intra-canalicular), group C (distal to superficial inguinal ring - pubic). Where no testis was found, a separate group D was assigned. The size of undescended testis at different locations in various age groups was compared with reference to normal descended testicular size in the respective age group, for statistical significance. ANOVA test was used for intergroup comparison for the size of undescended testis and Student t- test was applied for comparison with reference to normal values of the size of testis. A total of 102 patients with undescended testis were included in the study. The total number of 107 testicular units were assessed. Group I had 28, group II, 41 and group III, 38 testes. There were 24 intra-abdominal, 68 intra-canalicular and 12 pubic in location. In 3 cases, no testis was found at exploration. We found no statistically significant difference amongst groups (p-value=0.090) between the size of the undescended testis at different peroperative locations. The size of undescended testis grew with the age as undescended testis of larger size were found in older age group as compared to younger age group. By applying Student t-test, we did not find statistically significant difference in relation to the size of undescended testis in various age groups in comparison to the

Correlation of the size of undescended testis with its location in various age groups

International Nuclear Information System (INIS)

Taqvi, S.R.H.; Akhtar, J.; Batool, T.; Farhat, M.; Tabassum, R.

2006-01-01

To assess the correlation of the size of undescended testis with its location in children of various age groups, per- operatively. Children presenting with undescended testis at surgical outpatient were recruited. Physical examination and relevant investigations (haemoglobin, ultrasound for location and size of testes) were performed. Patients were divided randomly into three age groups, group I (8 months - 2.5 years), group II (2.6 - 8 years), group III (8.1-13 years). At orchiopexy location and size of undescended testis were noted. Patients were further sub-divided into groups according to peroperative location of undescended testis, group A (intra-abdominal), group B (intra-canalicular), group C (distal to superficial inguinal ring - pubic). Where no testis was found, a separate group D was assigned. The size of undescended testis at different locations in various age groups was compared with reference to normal descended testicular size in the respective age group, for statistical significance. ANOVA test was used for intergroup comparison for the size of undescended testis and Student t- test was applied for comparison with reference to normal values of the size of testis. A total of 102 patients with undescended testis were included in the study. The total number of 107 testicular units were assessed. Group I had 28, group II, 41 and group III, 38 testes. There were 24 intra-abdominal, 68 intra-canalicular and 12 pubic in location. In 3 cases, no testis was found at exploration. We found no statistically significant difference amongst groups (p-value=0.090) between the size of the undescended testis at different peroperative locations. The size of undescended testis grew with the age as undescended testis of larger size were found in older age group as compared to younger age group. By applying Student t-test, we did not find statistically significant difference in relation to the size of undescended testis in various age groups in comparison to the

Academic Procrastination and the Performance of Graduate-Level Cooperative Groups in Research Methods Courses

Science.gov (United States)

Jiao, Qun G.; DaRos-Voseles, Denise A.; Collins, Kathleen M. T.; Onwuegbuzie, Anthony J.

2011-01-01

This study examined the extent to which academic procrastination predicted the performance of cooperative groups in graduate-level research methods courses. A total of 28 groups was examined (n = 83 students), ranging in size from 2 to 5 (M = 2.96, SD = 1.10). Multiple regression analyses revealed that neither within-group mean nor within-group…

Resolving Microzooplankton Functional Groups In A Size-Structured Planktonic Model

Science.gov (United States)

Taniguchi, D.; Dutkiewicz, S.; Follows, M. J.; Jahn, O.; Menden-Deuer, S.

2016-02-01

Microzooplankton are important marine grazers, often consuming a large fraction of primary productivity. They consist of a great diversity of organisms with different behaviors, characteristics, and rates. This functional diversity, and its consequences, are not currently reflected in large-scale ocean ecological simulations. How should these organisms be represented, and what are the implications for their biogeography? We develop a size-structured, trait-based model to characterize a diversity of microzooplankton functional groups. We compile and examine size-based laboratory data on the traits, revealing some patterns with size and functional group that we interpret with mechanistic theory. Fitting the model to the data provides parameterizations of key rates and properties, which we employ in a numerical ocean model. The diversity of grazing preference, rates, and trophic strategies enables the coexistence of different functional groups of micro-grazers under various environmental conditions, and the model produces testable predictions of the biogeography.

Classification of video sequences into chosen generalized use classes of target size and lighting level.

Science.gov (United States)

Leszczuk, Mikołaj; Dudek, Łukasz; Witkowski, Marcin

The VQiPS (Video Quality in Public Safety) Working Group, supported by the U.S. Department of Homeland Security, has been developing a user guide for public safety video applications. According to VQiPS, five parameters have particular importance influencing the ability to achieve a recognition task. They are: usage time-frame, discrimination level, target size, lighting level, and level of motion. These parameters form what are referred to as Generalized Use Classes (GUCs). The aim of our research was to develop algorithms that would automatically assist classification of input sequences into one of the GUCs. Target size and lighting level parameters were approached. The experiment described reveals the experts' ambiguity and hesitation during the manual target size determination process. However, the automatic methods developed for target size classification make it possible to determine GUC parameters with 70 % compliance to the end-users' opinion. Lighting levels of the entire sequence can be classified with an efficiency reaching 93 %. To make the algorithms available for use, a test application has been developed. It is able to process video files and display classification results, the user interface being very simple and requiring only minimal user interaction.

Increased body size along urbanization gradients at both community and intraspecific level in macro-moths.

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Merckx, Thomas; Kaiser, Aurélien; Van Dyck, Hans

2018-05-23

Urbanization involves a cocktail of human-induced rapid environmental changes and is forecasted to gain further importance. Urban-heat-island effects result in increased metabolic costs expected to drive shifts towards smaller body sizes. However, urban environments are also characterized by strong habitat fragmentation, often selecting for dispersal phenotypes. Here, we investigate to what extent, and at which spatial scale(s), urbanization drives body size shifts in macro-moths-an insect group characterized by positive size-dispersal links-at both the community and intraspecific level. Using light and bait trapping as part of a replicated, spatially nested sampling design, we show that despite the observed urban warming of their woodland habitat, macro-moth communities display considerable increases in community-weighted mean body size because of stronger filtering against small species along urbanization gradients. Urbanization drives intraspecific shifts towards increased body size too, at least for a third of species analysed. These results indicate that urbanization drives shifts towards larger, and hence, more mobile species and individuals in order to mitigate low connectivity of ecological resources in urban settings. Macro-moths are a key group within terrestrial ecosystems, and since body size is central to species interactions, such urbanization-driven phenotypic change may impact urban ecosystem functioning, especially in terms of nocturnal pollination and food web dynamics. Although we show that urbanization's size-biased filtering happens simultaneously and coherently at both the inter- and intraspecific level, we demonstrate that the impact at the community level is most pronounced at the 800 m radius scale, whereas species-specific size increases happen at local and landscape scales (50-3,200 m radius), depending on the species. Hence, measures-such as creating and improving urban green infrastructure-to mitigate the effects of urbanization on

Accounting for One-Group Clustering in Effect-Size Estimation

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Citkowicz, Martyna; Hedges, Larry V.

2013-01-01

In some instances, intentionally or not, study designs are such that there is clustering in one group but not in the other. This paper describes methods for computing effect size estimates and their variances when there is clustering in only one group and the analysis has not taken that clustering into account. The authors provide the effect size…

Estimation of Tooth Size Discrepancies among Different Malocclusion Groups.

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Hasija, Narender; Bala, Madhu; Goyal, Virender

2014-05-01

Regards and Tribute: Late Dr Narender Hasija was a mentor and visionary in the light of knowledge and experience. We pay our regards with deepest gratitude to the departed soul to rest in peace. Bolton's ratios help in estimating overbite, overjet relationships, the effects of contemplated extractions on posterior occlusion, incisor relationships and identification of occlusal misfit produced by tooth size discrepancies. To determine any difference in tooth size discrepancy in anterior as well as overall ratio in different malocclusions and comparison with Bolton's study. After measuring the teeth on all 100 patients, Bolton's analysis was performed. Results were compared with Bolton's means and standard deviations. The results were also subjected to statistical analysis. Results show that the mean and standard deviations of ideal occlusion cases are comparable with those Bolton but, when the mean and standard deviation of malocclusion groups are compared with those of Bolton, the values of standard deviation are higher, though the mean is comparable. How to cite this article: Hasija N, Bala M, Goyal V. Estimation of Tooth Size Discrepancies among Different Malocclusion Groups. Int J Clin Pediatr Dent 2014;7(2):82-85.

Liquidity Determinants of the Selected Banking Sectors and their Size Groups

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Jana Laštůvková

2016-01-01

Full Text Available The article focuses on the factors affecting the liquidity of selected bank sectors, as well as their size groups, using panel regression analysis. For higher complexity of the results, multiple dependent variables are used: liquidity creation, outflow and net change. The values are calculated based on the specific method of liquidity risk measurement – gross liquidity flows. The results indicate both multiple effects of some factors on the given variables, as well as isolated influence of factors on a single liquidity form or size group. Thus, when looking for determinants using just one form of liquidity, such as creation, the results need not necessarily comprehensively show the influence of the given factors, and can lead to erroneous conclusions. The results also point to the differing behaviours of the size groups and their different sensitivity on the factors; smaller banks have shown higher sensitivity on macroeconomic variables. Higher flexibility in regulation could lead to higher optimization.

Why and how selection patterns in classroom networks differ between students.The potential influence of networks size preferences, level of information, and group membership.

Directory of Open Access Journals (Sweden)

Baerveldt, Chris

2010-12-01

Full Text Available High school students can select class mates for new friendships using a repertoire of patterns. They can actively pursue new friendships, make use of the existing network structure, and/ or use the scarce and often erroneous information about candidates. In this theoretical paper, we argue that such selection patterns should not be studied as the result of general rules, as is usually done in social network studies. Specifically, we state that network size preferences, the level of information about individual attributes of fellow classmates, and group membership are likely to differ among high school students, and that as a result, also their selection patterns are likely to be different. In this paper we sketch the theoretical articulations between these.

Individual and group-level job resources and their relationships with individual work engagement.

Science.gov (United States)

Füllemann, Désirée; Brauchli, Rebecca; Jenny, Gregor J; Bauer, Georg F

2016-06-16

This study adds a multilevel perspective to the well-researched individual-level relationship between job resources and work engagement. In addition, we explored whether individual job resources cluster within work groups because of a shared psychosocial environment and investigated whether a resource-rich psychosocial work group environment is beneficial for employee engagement over and above the beneficial effect of individual job resources and independent of their variability within groups. Data of 1,219 employees nested in 103 work groups were obtained from a baseline employee survey of a large stress management intervention project implemented in six medium and large-sized organizations in diverse sectors. A variety of important job resources were assessed and grouped to an overall job resource factor with three subfactors (manager behavior, peer behavior, and task-related resources). Data were analyzed using multilevel random coefficient modeling. The results indicated that job resources cluster within work groups and can be aggregated to a group-level job resources construct. However, a resource-rich environment, indicated by high group-level job resources, did not additionally benefit employee work engagement but on the contrary, was negatively related to it. On the basis of this unexpected result, replication studies are encouraged and suggestions for future studies on possible underlying within-group processes are discussed. The study supports the presumed value of integrating work group as a relevant psychosocial environment into the motivational process and indicates a need to further investigate emergent processes involved in aggregation procedures across levels.

Optimal Multi-Level Lot Sizing for Requirements Planning Systems

OpenAIRE

Earle Steinberg; H. Albert Napier

1980-01-01

The wide spread use of advanced information systems such as Material Requirements Planning (MRP) has significantly altered the practice of dependent demand inventory management. Recent research has focused on development of multi-level lot sizing heuristics for such systems. In this paper, we develop an optimal procedure for the multi-period, multi-product, multi-level lot sizing problem by modeling the system as a constrained generalized network with fixed charge arcs and side constraints. T...

Dolphin underwater bait-balling behaviors in relation to group and prey ball sizes.

Science.gov (United States)

Vaughn-Hirshorn, Robin L; Muzi, Elisa; Richardson, Jessica L; Fox, Gabriella J; Hansen, Lauren N; Salley, Alyce M; Dudzinski, Kathleen M; Würsig, Bernd

2013-09-01

We characterized dusky dolphin (Lagenorhynchus obscurus) feeding behaviors recorded on underwater video, and related behaviors to variation in prey ball sizes, dolphin group sizes, and study site (Argentina versus New Zealand, NZ). Herding behaviors most often involved dolphins swimming around the side or under prey balls, but dolphins in Argentina more often swam under prey balls (48% of passes) than did dolphins in NZ (34% of passes). This result may have been due to differences in group sizes between sites, since groups are larger in Argentina. Additionally, in NZ, group size was positively correlated with proportion of passes that occurred under prey balls (pdolphins in Argentina more often swam through prey balls (8% of attempts) than did dolphins in NZ (4% of attempts). This result may have been due to differences in prey ball sizes between sites, since dolphins fed on larger prey balls in Argentina (>74m(2)) than in NZ (maximum 33m(2)). Additionally, in NZ, dolphins were more likely to swim through prey balls to capture fish when they fed on larger prey balls (p=0.025). Copyright © 2013 Elsevier B.V. All rights reserved.

Evolution of students’ friendship networks: Examining the influence of group size

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Valentina Sokolovska

2017-01-01

Full Text Available  The main aim of this study was to examine the effect of the network size on formation and evolution of students’ friendship relations. Data was collected from two groups of sociology freshmen: a group from the University of Belgrade, which represents a larger group, and a group from the University of Novi Sad, which represents a smaller group. The data was collected in three periods of one academic year. We analyzed the structural features of students’ networks and constructed a stochastic model of network evolution in order to explore how friendships form and change during one year. The results showed that structural features of the larger and the smaller group differ in each stage of friendship formation. At the beginning of group forming, small world structure was noticeable in the larger group, although full small world structure was not confirmed in both groups. Furthermore, transitivity of triads had effect on the evolution of the larger network, while balance or structural equivalence had effect on the evolution of the smaller network. Results of the structural analysis are in line with findings of the network evolution model and together they provide an insight into how friendship evolves in groups of different sizes.

The role of micro size computing clusters for small physics groups

International Nuclear Information System (INIS)

Shevel, A Y

2014-01-01

A small physics group (3-15 persons) might use a number of computing facilities for the analysis/simulation, developing/testing, teaching. It is discussed different types of computing facilities: collaboration computing facilities, group local computing cluster (including colocation), cloud computing. The author discuss the growing variety of different computing options for small groups and does emphasize the role of the group owned computing cluster of micro size.

Two-level method with coarse space size independent convergence

Energy Technology Data Exchange (ETDEWEB)

Vanek, P.; Brezina, M. [Univ. of Colorado, Denver, CO (United States); Tezaur, R.; Krizkova, J. [UWB, Plzen (Czech Republic)

1996-12-31

The basic disadvantage of the standard two-level method is the strong dependence of its convergence rate on the size of the coarse-level problem. In order to obtain the optimal convergence result, one is limited to using a coarse space which is only a few times smaller than the size of the fine-level one. Consequently, the asymptotic cost of the resulting method is the same as in the case of using a coarse-level solver for the original problem. Today`s two-level domain decomposition methods typically offer an improvement by yielding a rate of convergence which depends on the ratio of fine and coarse level only polylogarithmically. However, these methods require the use of local subdomain solvers for which straightforward application of iterative methods is problematic, while the usual application of direct solvers is expensive. We suggest a method diminishing significantly these difficulties.

Lot Sizing Based on Stochastic Demand and Service Level Constraint

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hajar shirneshan

2012-06-01

Full Text Available Considering its application, stochastic lot sizing is a significant subject in production planning. Also the concept of service level is more applicable than shortage cost from managers' viewpoint. In this paper, the stochastic multi period multi item capacitated lot sizing problem has been investigated considering service level constraint. First, the single item model has been developed considering service level and with no capacity constraint and then, it has been solved using dynamic programming algorithm and the optimal solution has been derived. Then the model has been generalized to multi item problem with capacity constraint. The stochastic multi period multi item capacitated lot sizing problem is NP-Hard, hence the model could not be solved by exact optimization approaches. Therefore, simulated annealing method has been applied for solving the problem. Finally, in order to evaluate the efficiency of the model, low level criterion has been used .

Comparison of feeding behavior between two different-sized groups of Japanese macaques (Macaca fuscata yakui).

Science.gov (United States)

Kurihara, Yosuke; Hanya, Goro

2015-05-13

Group-living animals face intragroup scramble and intergroup contest competitions. Many studies have shown that larger groups bear the costs of intragroup scramble competition, which negatively affects the reproductive success of females. Unlike most primate species, Japanese macaques in the Yakushima coastal forest show increased reproductive success with group size. However, it remains unclear how group size affects the behavior of macaques. The present study examined the effects of group size on the feeding behavior of Japanese macaques in the Yakushima coastal forest. We investigated 9-13 adult females from two different-sized groups via focal animal sampling during October 2012-August 2013. We compared the feeding behavior, including patch use, between the two groups. The larger group had a larger home range and spent more time feeding, especially on mature leaves. This suggests that intragroup feeding competition should be more intense in the larger group than in the smaller group. The feeding of mature leaves might enable the larger group to increase the number of co-feeding individuals. Contrary to the predictions that the larger group travels longer distances and spends more time moving, the smaller group traveled longer distances, and spent more time moving, although the number of visited patches did not differ between the two groups. The immediate consequences of the loss of inter-group encounters could accumulate as daily travel costs, considering that group size is associated with inter-group dominance and that intergroup aggressive encounters occur frequently in the Yakushima coastal forest. This suggests that the smaller group has increased travel costs as a result of intergroup contest competition, which leads to decline in reproductive success. Am. J. Primatol. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Intergroup Discrimination in Positive and Negative Outcome Allocations: Impact of Stimulus Valence, Relative Group Status, and Relative Group Size.

Science.gov (United States)

Otten, Sabine; And Others

1996-01-01

Three studies investigated the determination of social discrimination by the valence of stimuli that are allocated between groups. The studies were based on either the minimal group paradigm or a more reality-based laboratory intergroup setting, with stimulus valence, group status, and group size as factors and with pull scores on Tajfel matrices…

Structural features and electronic properties of group-III-, group-IV-, and group-V-doped Si nanocrystallites

International Nuclear Information System (INIS)

Ramos, L E; Degoli, Elena; Cantele, G; Ossicini, Stefano; Ninno, D; Furthmueller, J; Bechstedt, F

2007-01-01

We investigate the incorporation of group-III (B and Al), group-IV (C and Ge), and group-V (N and P) impurities in Si nanocrystallites. The structural features and electronic properties of doped Si nanocrystallites, which are faceted or spherical-like, are studied by means of an ab initio pseudopotential method including spin polarization. Jahn-Teller distortions occur in the neighborhood of the impurity sites and the bond lengths show a dependence on size and shape of the nanocrystallites. We find that the acceptor (group-III) and donor (group-V) levels become deep as the nanocrystallites become small. The energy difference between the spin-up and spin-down levels of group-III and group-V impurities decreases as the size of the Si nanocrystallite increases and tends to the value calculated for Si bulk. Doping with carbon introduces an impurity-related level in the energy gap of the Si nanocrystallites

Predation, scramble competition, and the vigilance group size effect in dark-eyed juncos (Junco hyemalis)

Science.gov (United States)

Steven L. Lima; Patrick A. Zollner; Peter A. Bednekoff

1999-01-01

In socially feeding birds and mammals, as group size increases, individuals devote less time to scanning their environment and more time to feeding. This vigilance "group size effect" has long been attributed to the anti-predatory benefits of group living, but many investigators have suggested that this effect may be driven by scramble competition for limited...

Habitat, density and group size of primates in a Brazilian tropical forest.

Science.gov (United States)

Pinto, L P; Costa, C M; Strier, K B; da Fonseca, G A

1993-01-01

Habitats, population densities and group sizes of 5 primate species (Callithrix flaviceps, Callicebus personatus personatus, Cebus apella nigritus, Alouatta fusca clamitans, and Brachyteles arachnoides) were estimated, using the method of repeated transect sampling, in an area of montane pluvial forest in eastern Brazil (Atlantic forest). A. fusca and C. apella had the highest densities in terms of groups and individuals per square kilometer, respectively, while B. arachnoides was least abundant. The highest primate densities were observed in areas of secondary vegetation. Both group sizes and population densities for the 5 species were generally lower at the Reserva Biologica Augusto Ruschi than those reported in other areas of Atlantic forest. Hunting pressure and the different carrying capacity of the habitat are suggested as possible causes for the low number of sightings registered for these species.

Relating group size and posting activity of an online community of financial investors: Regularities and seasonal patterns

Science.gov (United States)

Racca, P.; Casarin, R.; Dondio, P.; Squazzoni, F.

2018-03-01

Group size can potentially affect collective activity and individual propensity to contribute to collective goods. Mancur Olson, in his Logic of Collective Action, argued that individual contribution to a collective good tends to be lower in groups of large size. Today, online communication platforms represent an interesting ground to study such collaborative dynamics under possibly different conditions (e.g., lower costs related to gather and share information). This paper examines the relationship between group size and activity in an online financial forum, where users invest time in sharing news, analysis and comments with other investors. We looked at about 24 million messages shared in more than ten years in the finanzaonline.com online forum. We found that the relationship between the number of active users and the number of posts shared by those users is of the power type (with exponent α > 1) and is subject to periodic fluctuations, mostly driven by hour-of-the-day and day-of-the-week effects. The daily patterns of the exponent showed a divergence between working week and weekend days. In general, the exponent was lower before noon, where investors are typically interested in market news, higher in the late afternoon, where markets are closing and investors need better understanding of the situation. Further research is needed, especially at the micro level, to dissect the mechanisms behind these regularities.

The Influence of Social Comparison and Peer Group Size on Risky Decision-Making.

Science.gov (United States)

Wang, Dawei; Zhu, Liping; Maguire, Phil; Liu, Yixin; Pang, Kaiyuan; Li, Zhenying; Hu, Yixin

2016-01-01

This study explores the influence of different social reference points and different comparison group sizes on risky decision-making. Participants were presented with a scenario describing an exam, and presented with the opportunity of making a risky decision in the context of different information provided about the performance of their peers. We found that behavior was influenced, not only by comparison with peers, but also by the size of the comparison group. Specifically, the larger the reference group, the more polarized the behavior it prompted. In situations describing social loss, participants were led to make riskier decisions after comparing themselves against larger groups, while in situations describing social gain, they become more risk averse. These results indicate that decision making is influenced both by social comparison and the number of people making up the social reference group.

Stepwise latent class models for explaining group-level putcomes using discrete individual-level predictors

NARCIS (Netherlands)

Bennink, Margot; Croon, M.A.; Vermunt, J.K.

2015-01-01

Explaining group-level outcomes from individual-level predictors requires aggregating the individual-level scores to the group level and correcting the group-level estimates for measurement errors in the aggregated scores. However, for discrete variables it is not clear how to perform the

Surface-Level Diversity and Decision-Making in Groups: When Does Deep-Level Similarity Help?

OpenAIRE

2006-01-01

Abstract We examined how surface-level diversity (based on race) and deep-level similarities influenced three-person decision-making groups on a hidden-profile task. Surface-level homogeneous groups perceived their information to be less unique and spent less time on the task than surface-level diverse groups. When the groups were given the opportunity to learn about their deep-level similarities prior to t...

Functional groups and reactivity of size-fractionated Aldrich humic acid

Energy Technology Data Exchange (ETDEWEB)

Tanaka, Tadao, E-mail: tanaka.tadao26@jaea.go.jp [Nuclear Safety Research Center, Japan Atomic Energy Agency, Shirakata 2-4, Tokai, Naka, Ibaraki, 319-1195 (Japan)

2012-03-20

The complexation affinity of the Aldrich Chemicals humic acid with {sup 60}Co was examined with respect to molecular size of humic acid. Correlations between the affinity and the structures of humic acid were studied. At low humic acid concentration range, {sup 60}Co was interacted with the humic acid of size fraction over 100k Da (HA(100<)). With increasing humic acid concentration, the {sup 60}Co was preferentially interacted with the 30k-100k Da of humic acid (HA(30-100)). Fractionated HA(100<) and HA(30-100) were characterized from their FTIR (Fourier Transform Infra-Red), {sup 13}C NMR spectral analyses and acid-base titration curves. The HA(10<) having aliphatic branched structure, smaller amount of COOH group and large proton exchangeable capacity, seem to show low covalent bonding nature and high ion exchangeability in the complexation. In addition, steric hindrance may affect on the complexation, by winding up like random coils from the branched structure. The HA(30-100) is dominated with the aromatic COOH group and OH group and it may preferentially coordinate to {sup 60}Co by covalent binding. These presumptions were supported by XPS analysis, in which the biding energy of cobalt-humates was discussed.

Effects of group size on behaviour, growth and occurrence of bite marks in farmed mink

DEFF Research Database (Denmark)

Axelsson, Helene M. K.; Hansen, Steffen W.; Loberg, Jenny

2017-01-01

The aims of this study were to investigate the occurrence of stereotypic behaviours and the activity level in farmed mink when group housed in climbing cages and if group housing increase aggression by assessing the prevalence of bite marks. This was studied in juvenile mink of the colour types...... sunset during six periods of five days each from August-October. After pelting, the leather side of the undried skins were visually inspected for bite marks. Stereotypic behaviours were infrequent (0.1% of observations). Pair housed mink in climbing cages were more "inactive out in cage" than pair housed...... mink in standard cages (p 0.0001), but cage type had no effect on the behaviours "being in nest box", "active out in cage", "interactions with enrichments" or "social interactions" (n.s.). Group sizes of three or four mink increased the behaviours "active out in cage" (P 0.0001) and decreased "being...

Comparing radio-tracking and visual detection methods to quantify group size measures

Directory of Open Access Journals (Sweden)

Reiczigel Jenő

2015-12-01

Full Text Available 1. Average values of animal group sizes are prone to be overestimated in traditional field studies because small groups and singletons are easier to overlook than large ones. This kind of bias also applies for the method of locating groups by tracking previously radio-collared individuals in the wild. If the researcher randomly chooses a collared animal to locate a group to visit, a large group has higher probability to be selected than a small one, simply because it has more members.

Within-Group Effect-Size Benchmarks for Trauma-Focused Cognitive Behavioral Therapy with Children and Adolescents

Science.gov (United States)

Rubin, Allen; Washburn, Micki; Schieszler, Christine

2017-01-01

Purpose: This article provides benchmark data on within-group effect sizes from published randomized clinical trials (RCTs) supporting the efficacy of trauma-focused cognitive behavioral therapy (TF-CBT) for traumatized children. Methods: Within-group effect-size benchmarks for symptoms of trauma, anxiety, and depression were calculated via the…

Natural endocrine profiles of the group-living skunk anemonefish Amphiprion akallopisos in relation to their size-based dominance hierarchy.

Science.gov (United States)

Mills, S C; O'Donnell, J L; Bernardi, G; Beldade, R

2018-03-01

Group-living animals commonly display differences in behaviour, physiology and endocrine profiles between conspecifics within the group, which are tightly linked to reproduction. Teleosts exhibit a variety of social systems, where social status, as well as sex, has been linked to different androgen and oestrogen profiles. Levels of gonadal androgen and oestrogen were investigated as a function of sex and position in a social hierarchy in free-living individuals of the skunk anemonefish Amphiprion akallopisos, a protandrous pomacentrid fish with a size-based dominance hierarchical social system. Plasma levels of 11-ketotestosterone (11-KT), testosterone (T) and 17β-oestradiol (E 2 ), as well as conversion ratios from T, were measured by ELISA from 111 individuals along a linear hierarchy from 38 social groups in the wild. Blood plasma levels of 11-KT and E 2 showed sex differences, being higher in males and females respectively as expected based on their role as the major androgen and oestrogen in fish reproduction. However, no sex differences were found for T, which may represent its role in territorial defence or simply as a precursor for the synthesis of 11-KT and E 2 . In terms of the hierarchical social system within males, 11-KT levels decline as the hierarchy is descended, which may represent their decreasing reproductive opportunity, as well as the decreasing levels of aggression towards males lower in the hierarchy. In summary, the size-based dominance hierarchy is associated with distinct steroid levels of 11-KT and E 2 between individual free-living A. akallopisos that closely resemble those of species in which breeding individuals suppress reproduction of conspecifics lower in the hierarchy. © 2018 The Fisheries Society of the British Isles.

Item response theory at subject- and group-level

NARCIS (Netherlands)

Tobi, Hilde

1990-01-01

This paper reviews the literature about item response models for the subject level and aggregated level (group level). Group-level item response models (IRMs) are used in the United States in large-scale assessment programs such as the National Assessment of Educational Progress and the California

Does Group-Level Commitment Predict Employee Well-Being?

DEFF Research Database (Denmark)

Clausen, Thomas; Christensen, Karl Bang; Nielsen, Karina

2015-01-01

OBJECTIVE: To investigate the links between group-level affective organizational commitment (AOC) and individual-level psychological well-being, self-reported sickness absence, and sleep disturbances. METHODS: A total of 5085 care workers from 301 workgroups in the Danish eldercare services parti...... disturbances (T2) were partially mediated by individual-level AOC (T1). CONCLUSIONS: Group-level AOC is an important predictor of employee well-being in contemporary health care organizations.......OBJECTIVE: To investigate the links between group-level affective organizational commitment (AOC) and individual-level psychological well-being, self-reported sickness absence, and sleep disturbances. METHODS: A total of 5085 care workers from 301 workgroups in the Danish eldercare services...

Optimizing trial design in pharmacogenetics research: comparing a fixed parallel group, group sequential, and adaptive selection design on sample size requirements.

Science.gov (United States)

Boessen, Ruud; van der Baan, Frederieke; Groenwold, Rolf; Egberts, Antoine; Klungel, Olaf; Grobbee, Diederick; Knol, Mirjam; Roes, Kit

2013-01-01

Two-stage clinical trial designs may be efficient in pharmacogenetics research when there is some but inconclusive evidence of effect modification by a genomic marker. Two-stage designs allow to stop early for efficacy or futility and can offer the additional opportunity to enrich the study population to a specific patient subgroup after an interim analysis. This study compared sample size requirements for fixed parallel group, group sequential, and adaptive selection designs with equal overall power and control of the family-wise type I error rate. The designs were evaluated across scenarios that defined the effect sizes in the marker positive and marker negative subgroups and the prevalence of marker positive patients in the overall study population. Effect sizes were chosen to reflect realistic planning scenarios, where at least some effect is present in the marker negative subgroup. In addition, scenarios were considered in which the assumed 'true' subgroup effects (i.e., the postulated effects) differed from those hypothesized at the planning stage. As expected, both two-stage designs generally required fewer patients than a fixed parallel group design, and the advantage increased as the difference between subgroups increased. The adaptive selection design added little further reduction in sample size, as compared with the group sequential design, when the postulated effect sizes were equal to those hypothesized at the planning stage. However, when the postulated effects deviated strongly in favor of enrichment, the comparative advantage of the adaptive selection design increased, which precisely reflects the adaptive nature of the design. Copyright © 2013 John Wiley & Sons, Ltd.

An integrated approach for determining the size of hardwood group-selection openings

Science.gov (United States)

Chris B. LeDoux

1999-01-01

The use of group-selection methods is becoming more widespread as landowners and forest managers attempt to respond to public pressure to reduce the size of clearcut blocks. Several studies have shown that harvesting timber in smaller groups or clumps increases the cost of operations for both cable and ground-based logging systems. Recent regeneration studies have...

Viral Richness is Positively Related to Group Size, but Not Mating System, in Bats.

Science.gov (United States)

Webber, Quinn M R; Fletcher, Quinn E; Willis, Craig K R

2017-12-01

Characterizing host traits that influence viral richness and diversification is important for understanding wildlife pathogens affecting conservation and/or human health. Behaviors that affect contact rates among hosts could be important for viral diversification because more frequent intra- and inter-specific contacts among hosts should increase the potential for viral diversification within host populations. We used published data on bats to test the contact-rate hypothesis. We predicted that species forming large conspecific groups, that share their range with more heterospecifics (i.e., sympatry), and with mating systems characterized by high contact rates (polygynandry: multi-male/multi-female), would host higher viral richness than species with small group sizes, lower sympatry, or low contact-rate mating systems (polygyny: single male/multi-female). Consistent with our hypothesis and previous research, viral richness was positively correlated with conspecific group size although the relationship plateaued at group sizes of approximately several hundred thousand bats. This pattern supports epidemiological theory that, up to a point, larger groups have higher contact rates, greater likelihood of acquiring and transmitting viruses, and ultimately greater potential for viral diversification. However, contrary to our hypothesis, there was no effect of sympatry on viral richness and no difference in viral richness between mating systems. We also found no residual effect of host phylogeny on viral richness, suggesting that closely related species do not necessarily host similar numbers of viruses. Our results support the contact-rate hypothesis that intra-specific viral transmission can enhance viral diversification within species and highlight the influence of host group size on the potential of viruses to propagate within host populations.

Group size adjustment to ecological demand in a cooperative breeder.

Science.gov (United States)

Zöttl, Markus; Frommen, Joachim G; Taborsky, Michael

2013-04-07

Environmental factors can determine which group size will maximize the fitness of group members. This is particularly important in cooperative breeders, where group members often serve different purposes. Experimental studies are yet lacking to check whether ecologically mediated need for help will change the propensity of dominant group members to accept immigrants. Here, we manipulated the perceived risk of predation for dominant breeders of the cooperatively breeding cichlid fish Neolamprologus pulcher to test their response to unrelated and previously unknown immigrants. Potential immigrants were more readily accepted if groups were exposed to fish predators or egg predators than to herbivorous fish or control situations lacking predation risk. Our data are consistent with both risk dilution and helping effects. Egg predators were presented before spawning, which might suggest that the fish adjust acceptance rates also to a potential future threat. Dominant group members of N. pulcher apparently consider both present and future need of help based on ecological demand. This suggests that acceptance of immigrants and, more generally, tolerance of group members on demand could be a widespread response to ecological conditions in cooperatively breeding animals.

Whistle rates of wild bottlenose dolphins (Tursiops truncatus): influences of group size and behavior.

Science.gov (United States)

Quick, Nicola J; Janik, Vincent M

2008-08-01

In large social groups acoustic communication signals are prone to signal masking by conspecific sounds. Bottlenose dolphins (Tursiops truncatus) use highly distinctive signature whistles that counter masking effects. However, they can be found in very large groups where masking by conspecific sounds may become unavoidable. In this study we used passive acoustic localization to investigate how whistle rates of wild bottlenose dolphins change in relation to group size and behavioral context. We found that individual whistle rates decreased when group sizes got larger. Dolphins displayed higher whistle rates in contexts when group members were more dispersed as in socializing and in nonpolarized movement than during coordinated surface travel. Using acoustic localization showed that many whistles were produced by groups nearby and not by our focal group. Thus, previous studies based on single hydrophone recordings may have been overestimating whistle rates. Our results show that although bottlenose dolphins whistle more in social situations they also decrease vocal output in large groups where the potential for signal masking by other dolphin whistles increases.

A Life-Cycle Model of Human Social Groups Produces a U-Shaped Distribution in Group Size.

Directory of Open Access Journals (Sweden)

Gul Deniz Salali

Full Text Available One of the central puzzles in the study of sociocultural evolution is how and why transitions from small-scale human groups to large-scale, hierarchically more complex ones occurred. Here we develop a spatially explicit agent-based model as a first step towards understanding the ecological dynamics of small and large-scale human groups. By analogy with the interactions between single-celled and multicellular organisms, we build a theory of group lifecycles as an emergent property of single cell demographic and expansion behaviours. We find that once the transition from small-scale to large-scale groups occurs, a few large-scale groups continue expanding while small-scale groups gradually become scarcer, and large-scale groups become larger in size and fewer in number over time. Demographic and expansion behaviours of groups are largely influenced by the distribution and availability of resources. Our results conform to a pattern of human political change in which religions and nation states come to be represented by a few large units and many smaller ones. Future enhancements of the model should include decision-making rules and probabilities of fragmentation for large-scale societies. We suggest that the synthesis of population ecology and social evolution will generate increasingly plausible models of human group dynamics.

Group size and nest success in red-cockaded woodpeckers in the West Gulf Coastal Plain: helpers make a difference

Science.gov (United States)

Richard N. Conner; Daniel Saenz; Richard R. Schaefer; James R. McCormick; D. Craig Rudolph; D. Brent Burt

2004-01-01

We studied the relationships between Red-cockaded Woodpecker (Picoides borealis) group size and nest productivity. Red-cockaded Woodpecker group size was positively correlated with fledging success. Although the relationships between woodpecker group size and nest productivity measures were nor statistically significant, a pattern of...

Relationship between Vocabulary Size and Reading Comprehension Levels of Malaysian Tertiary Students

Directory of Open Access Journals (Sweden)

Angelina Wan Lin Tan

2018-01-01

Full Text Available This study investigated the relationship between vocabulary size and reading comprehension performance among students in a tertiary institution in a Malaysian context and examined the vocabulary size required for students to achieve reading comprehension at various levels of proficiency. The research questions that guided this study were: 1 What is the vocabulary size of second year diploma students studying Mass Communication?; 2 What is the reading comprehension proficiency of second year diploma students studying Mass Communication?; and 3 What vocabulary size is required for different levels of reading comprehension proficiency? This study used the quantitative approach. The participants were 53 Malaysian second-year students at a private university college in Malaysia who were reading for their Diploma in Mass Communication. The instruments used were the Vocabulary Size Test and the IELTS Reading Test (Academic Module. The findings showed that the average vocabulary size of the students was just over 6000 word families and this vocabulary size was generally insufficient for adequate reading comprehension. Students needed an average vocabulary size of about 8000 word families to achieve adequate reading comprehension and about 10000 word families to achieve proficient reading comprehension. Based on the individual student’s performance, this study did not find a linear relationship between vocabulary size and reading comprehension performance, nor was there a threshold vocabulary size for adequate reading comprehension.

Beam size measurement at high radiation levels

International Nuclear Information System (INIS)

Decker, F.J.

1991-05-01

At the end of the Stanford Linear Accelerator the high energy electron and positron beams are quite small. Beam sizes below 100 μm (σ) as well as the transverse distribution, especially tails, have to be determined. Fluorescent screens observed by TV cameras provide a quick two-dimensional picture, which can be analyzed by digitization. For running the SLAC Linear Collider (SLC) with low backgrounds at the interaction point, collimators are installed at the end of the linac. This causes a high radiation level so that the nearby cameras die within two weeks and so-called ''radiation hard'' cameras within two months. Therefore an optical system has been built, which guides a 5 mm wide picture with a resolution of about 30 μm over a distance of 12 m to an accessible region. The overall resolution is limited by the screen thickness, optical diffraction and the line resolution of the camera. Vibration, chromatic effects or air fluctuations play a much less important role. The pictures are colored to get fast information about the beam current, size and tails. Beside the emittance, more information about the tail size and betatron phase is obtained by using four screens. This will help to develop tail compensation schemes to decrease the emittance growth in the linac at high currents. 4 refs., 2 figs

Micrometer-sized TPM emulsion droplets with surface-mobile binding groups

Science.gov (United States)

van der Wel, Casper; van de Stolpe, Guido L.; Verweij, Ruben W.; Kraft, Daniela J.

2018-03-01

Colloids coated with lipid membranes have been widely employed for fundamental studies of lipid membrane processes, biotechnological applications such as drug delivery and biosensing, and more recently, for self-assembly. The latter has been made possible by inserting DNA oligomers with covalently linked hydrophobic anchors into the membrane. The lateral mobility of the DNA linkers on micrometer-sized droplets and solid particles has opened the door to creating structures with unprecedented structural flexibility. Here, we investigate micro-emulsions of TPM (3-(trimethoxysilyl)propyl methacrylate) as a platform for lipid monolayers and further functionalization with proteins and DNA oligonucleotides. TPM droplets can be produced with a narrow size distribution and are polymerizable, thus providing supports for model lipid membranes with controlled size and curvature. With fluorescence recovery after photobleaching, we observed that droplet-attached lipids, NeutrAvidin proteins, as well as DNA oligonucleotides all show mobility on the surface. We explored the assembly of micron-sized particles on TPM-droplets by exploiting either avidin-biotin interactions or double-stranded DNA with complementary single-stranded end groups. While the single molecules are mobile, the particles that are attached to them are not. We propose that this is caused by the heterogeneous nature of emulsified TPM, which forms an oligomer network that limits the collective motion of linkers, but allows the surface mobility of individual molecules.

Reduced ferritin levels in individuals with non-O blood group

DEFF Research Database (Denmark)

Rigas, Andreas S; Berkfors, Adam A; Pedersen, Ole B

2017-01-01

stores expressed as ferritin levels. STUDY DESIGN AND METHODS: Ferritin levels were measured at least once for 30,595 Danish Blood Donor Study participants. Linear regression analyses were performed with the ABO blood group as explanatory variable and adjusted for age, number of donations 3 years before......BACKGROUND: Genomewide association studies have reported alleles in the ABO locus to be associated with ferritin levels. These studies warrant the investigation of a possible association between the ABO blood group and ferritin levels. We aimed to explore if ABO blood group is associated with iron...... blood group was associated with a ferritin level of less than 15 ng/mL. RESULTS: Non-O blood group donors had lower ferritin levels than blood group O donors, regardless of sex. Accordingly, risk of ferritin level of less than 15 ng/mL was increased for individuals with non-O blood group compared with O...

Investigations of internal noise levels for different target sizes, contrasts, and noise structures

Science.gov (United States)

Han, Minah; Choi, Shinkook; Baek, Jongduk

2014-03-01

To describe internal noise levels for different target sizes, contrasts, and noise structures, Gaussian targets with four different sizes (i.e., standard deviation of 2,4,6 and 8) and three different noise structures(i.e., white, low-pass, and highpass) were generated. The generated noise images were scaled to have standard deviation of 0.15. For each noise type, target contrasts were adjusted to have the same detectability based on NPW, and the detectability of CHO was calculated accordingly. For human observer study, 3 trained observers performed 2AFC detection tasks, and correction rate, Pc, was calculated for each task. By adding proper internal noise level to numerical observer (i.e., NPW and CHO), detectability of human observer was matched with that of numerical observers. Even though target contrasts were adjusted to have the same detectability of NPW observer, detectability of human observer decreases as the target size increases. The internal noise level varies for different target sizes, contrasts, and noise structures, demonstrating different internal noise levels should be considered in numerical observer to predict the detection performance of human observer.

Metastable structures and size effects in small group dynamics

Directory of Open Access Journals (Sweden)

Rosapia eLauro Grotto

2014-07-01

Full Text Available In his seminal works on group dynamics Bion defined a specific therapeutic setting allowing psychoanalytic observations on group phenomena. In describing the setting he proposed that the group was where his voice arrived. This physical limit was later made operative by assuming that the natural dimension of a therapeutic group is around 12 people. Bion introduced a theory of the group aspects of the mind in which proto-mental individual states spontaneously evolve into shared psychological states that are characterized by a series of features: 1 they emerge as a consequence of the natural tendency of (both conscious and unconscious emotions to combine into structured group patterns; 2 they have a certain degree of stability in time; 3 they tend to alternate so that the dissolution of one is rapidly followed by the emergence of another; 4 they can be described in qualitative terms according to the nature of the emotional mix that dominates the state, in structural terms by a kind of typical 'leadership’ pattern, and in 'cognitive’ terms by a set of implicit expectations that are helpful in explaining the group behavior (i.e. the group behaves 'as if’ it was assuming that…. Here we adopt a formal approach derived from Socio-physics in order to explore some of the structural and dynamic properties of this small group dynamics. We will described data from an analytic DS model simulating small group interactions of agents endowed with a very simplified emotional and cognitive dynamic in order to assess the following main points: 1 are metastable collective states allowed to emerge in the model and if so, under which conditions in the parameter space? 3 can these states be differentiated in structural terms? 3 to what extent are the emergent dynamic features of the systems dependent of the system size? We will finally discuss possible future applications of the quantitative descriptions of the interaction structure in the small group clinical

Metastable structures and size effects in small group dynamics.

Science.gov (United States)

Lauro Grotto, Rosapia; Guazzini, Andrea; Bagnoli, Franco

2014-01-01

In his seminal works on group dynamics Bion defined a specific therapeutic setting allowing psychoanalytic observations on group phenomena. In describing the setting he proposed that the group was where his voice arrived. This physical limit was later made operative by assuming that the natural dimension of a therapeutic group is around 12 people. Bion introduced a theory of the group aspects of the mind in which proto-mental individual states spontaneously evolve into shared psychological states that are characterized by a series of features: (1) they emerge as a consequence of the natural tendency of (both conscious and unconscious) emotions to combine into structured group patterns; (2) they have a certain degree of stability in time; (3) they tend to alternate so that the dissolution of one is rapidly followed by the emergence of another; (4) they can be described in qualitative terms according to the nature of the emotional mix that dominates the state, in structural terms by a kind of typical "leadership" pattern, and in "cognitive" terms by a set of implicit expectations that are helpful in explaining the group behavior (i.e., the group behaves "as if" it was assuming that). Here we adopt a formal approach derived from Socio-physics in order to explore some of the structural and dynamic properties of this small group dynamics. We will described data from an analytic DS model simulating small group interactions of agents endowed with a very simplified emotional and cognitive dynamic in order to assess the following main points: (1) are metastable collective states allowed to emerge in the model and if so, under which conditions in the parameter space? (2) can these states be differentiated in structural terms? (3) to what extent are the emergent dynamic features of the systems dependent of the system size? We will finally discuss possible future applications of the quantitative descriptions of the interaction structure in the small group clinical setting.

Low level of polyandry constrains phenotypic plasticity of male body size in mites.

Directory of Open Access Journals (Sweden)

Peter Schausberger

Full Text Available Polyandry, i.e. females mating with multiple males, is more common than previously anticipated and potentially provides both direct and indirect fitness benefits to females. The level of polyandry (defined by the lifetime number of male mates of a female is an important determinant of the occurrence and intensity of sexual selection acting on male phenotypes. While the forces of sexual selection acting on phenotypic male traits such as body size are relatively well understood, sexual selection acting on phenotypic plasticity of these traits is unexplored. We tackled this issue by scrutinizing the link between polyandry and phenotypic plasticity of male body size in two sympatric plant-inhabiting predatory mite species, Phytoseiulus persimilis and Neoseiulus californicus. These two species are similar in life history, ecological niche requirements, mating behavior, polygyny and female body size plasticity but strikingly differ in the level of both polyandry and phenotypic plasticity of male body size (both lower in P. persimilis. We hypothesized that deviations from standard body size, i.e. the size achieved under favorable conditions, incur higher costs for males in the less polyandrous P. persimilis. To test our hypotheses, we conducted two experiments on (i the effects of male body size on spermatophore transfer in singly mating females and (ii the effects of mate sequence (switching the order of standard-sized and small males on mating behavior and paternity success in doubly mating females. In P. persimilis but not N. californicus, small males transferred fewer but larger spermatophores to the females; in both species, females re-mated more likely with standard-sized following small than small following standard-sized males; in P. persimilis, first standard-sized males sired a higher proportion of offspring produced after re-mating by the female than first small males, whereas in N. californicus the paternity success of small and standard-sized

Low level of polyandry constrains phenotypic plasticity of male body size in mites.

Science.gov (United States)

Schausberger, Peter; Walzer, Andreas; Murata, Yasumasa; Osakabe, Masahiro

2017-01-01

Polyandry, i.e. females mating with multiple males, is more common than previously anticipated and potentially provides both direct and indirect fitness benefits to females. The level of polyandry (defined by the lifetime number of male mates of a female) is an important determinant of the occurrence and intensity of sexual selection acting on male phenotypes. While the forces of sexual selection acting on phenotypic male traits such as body size are relatively well understood, sexual selection acting on phenotypic plasticity of these traits is unexplored. We tackled this issue by scrutinizing the link between polyandry and phenotypic plasticity of male body size in two sympatric plant-inhabiting predatory mite species, Phytoseiulus persimilis and Neoseiulus californicus. These two species are similar in life history, ecological niche requirements, mating behavior, polygyny and female body size plasticity but strikingly differ in the level of both polyandry and phenotypic plasticity of male body size (both lower in P. persimilis). We hypothesized that deviations from standard body size, i.e. the size achieved under favorable conditions, incur higher costs for males in the less polyandrous P. persimilis. To test our hypotheses, we conducted two experiments on (i) the effects of male body size on spermatophore transfer in singly mating females and (ii) the effects of mate sequence (switching the order of standard-sized and small males) on mating behavior and paternity success in doubly mating females. In P. persimilis but not N. californicus, small males transferred fewer but larger spermatophores to the females; in both species, females re-mated more likely with standard-sized following small than small following standard-sized males; in P. persimilis, first standard-sized males sired a higher proportion of offspring produced after re-mating by the female than first small males, whereas in N. californicus the paternity success of small and standard-sized males was

What about N? A methodological study of sample-size reporting in focus group studies.

Science.gov (United States)

Carlsen, Benedicte; Glenton, Claire

2011-03-11

Focus group studies are increasingly published in health related journals, but we know little about how researchers use this method, particularly how they determine the number of focus groups to conduct. The methodological literature commonly advises researchers to follow principles of data saturation, although practical advise on how to do this is lacking. Our objectives were firstly, to describe the current status of sample size in focus group studies reported in health journals. Secondly, to assess whether and how researchers explain the number of focus groups they carry out. We searched PubMed for studies that had used focus groups and that had been published in open access journals during 2008, and extracted data on the number of focus groups and on any explanation authors gave for this number. We also did a qualitative assessment of the papers with regard to how number of groups was explained and discussed. We identified 220 papers published in 117 journals. In these papers insufficient reporting of sample sizes was common. The number of focus groups conducted varied greatly (mean 8.4, median 5, range 1 to 96). Thirty seven (17%) studies attempted to explain the number of groups. Six studies referred to rules of thumb in the literature, three stated that they were unable to organize more groups for practical reasons, while 28 studies stated that they had reached a point of saturation. Among those stating that they had reached a point of saturation, several appeared not to have followed principles from grounded theory where data collection and analysis is an iterative process until saturation is reached. Studies with high numbers of focus groups did not offer explanations for number of groups. Too much data as a study weakness was not an issue discussed in any of the reviewed papers. Based on these findings we suggest that journals adopt more stringent requirements for focus group method reporting. The often poor and inconsistent reporting seen in these

What about N? A methodological study of sample-size reporting in focus group studies

Directory of Open Access Journals (Sweden)

Glenton Claire

2011-03-01

Full Text Available Abstract Background Focus group studies are increasingly published in health related journals, but we know little about how researchers use this method, particularly how they determine the number of focus groups to conduct. The methodological literature commonly advises researchers to follow principles of data saturation, although practical advise on how to do this is lacking. Our objectives were firstly, to describe the current status of sample size in focus group studies reported in health journals. Secondly, to assess whether and how researchers explain the number of focus groups they carry out. Methods We searched PubMed for studies that had used focus groups and that had been published in open access journals during 2008, and extracted data on the number of focus groups and on any explanation authors gave for this number. We also did a qualitative assessment of the papers with regard to how number of groups was explained and discussed. Results We identified 220 papers published in 117 journals. In these papers insufficient reporting of sample sizes was common. The number of focus groups conducted varied greatly (mean 8.4, median 5, range 1 to 96. Thirty seven (17% studies attempted to explain the number of groups. Six studies referred to rules of thumb in the literature, three stated that they were unable to organize more groups for practical reasons, while 28 studies stated that they had reached a point of saturation. Among those stating that they had reached a point of saturation, several appeared not to have followed principles from grounded theory where data collection and analysis is an iterative process until saturation is reached. Studies with high numbers of focus groups did not offer explanations for number of groups. Too much data as a study weakness was not an issue discussed in any of the reviewed papers. Conclusions Based on these findings we suggest that journals adopt more stringent requirements for focus group method

A re-examination of the effect of contextual group size on people's attitude to risk

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Kazumi Shimizu

2011-02-01

Full Text Available Using Kahneman and Tversky's life-death decision paradigm, Wang and colleagues (e.g., Wang and Johnston, 1995; Wang, 1996a, 1996b, 1996c, 2008; Wang et al., 2001 have shown two characteristic phenomena regarding people's attitude to risk when the contextual group size is manipulated. In both positive and negative frames, people tend to take greater risks in life-death decisions as the contextual group size becomes smaller; this risk-seeking attitude is greater when framed positively than negatively. (This second characteristic often leads to the disappearance of the framing effect in small group contexts comprising of 6 or 60 people. Their results could shed new light on the effect of contextual group size on people's risk choice. However these results are usually observed in laboratory experiments with university student samples. This study aims to examine the external validity of these results through different ways of experimentation and with a different sample base. The first characteristic was replicated in both a face-to-face interview with a randomly selected sample of the Japanese general public, and a web-based experiment with a non-student sample, but not the second.

Bayesian Group Bridge for Bi-level Variable Selection.

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Mallick, Himel; Yi, Nengjun

2017-06-01

A Bayesian bi-level variable selection method (BAGB: Bayesian Analysis of Group Bridge) is developed for regularized regression and classification. This new development is motivated by grouped data, where generic variables can be divided into multiple groups, with variables in the same group being mechanistically related or statistically correlated. As an alternative to frequentist group variable selection methods, BAGB incorporates structural information among predictors through a group-wise shrinkage prior. Posterior computation proceeds via an efficient MCMC algorithm. In addition to the usual ease-of-interpretation of hierarchical linear models, the Bayesian formulation produces valid standard errors, a feature that is notably absent in the frequentist framework. Empirical evidence of the attractiveness of the method is illustrated by extensive Monte Carlo simulations and real data analysis. Finally, several extensions of this new approach are presented, providing a unified framework for bi-level variable selection in general models with flexible penalties.

Genome size evolution at the speciation level: the cryptic species complex Brachionus plicatilis (Rotifera).

Science.gov (United States)

Stelzer, Claus-Peter; Riss, Simone; Stadler, Peter

2011-04-07

Studies on genome size variation in animals are rarely done at lower taxonomic levels, e.g., slightly above/below the species level. Yet, such variation might provide important clues on the tempo and mode of genome size evolution. In this study we used the flow-cytometry method to study the evolution of genome size in the rotifer Brachionus plicatilis, a cryptic species complex consisting of at least 14 closely related species. We found an unexpectedly high variation in this species complex, with genome sizes ranging approximately seven-fold (haploid '1C' genome sizes: 0.056-0.416 pg). Most of this variation (67%) could be ascribed to the major clades of the species complex, i.e. clades that are well separated according to most species definitions. However, we also found substantial variation (32%) at lower taxonomic levels--within and among genealogical species--and, interestingly, among species pairs that are not completely reproductively isolated. In one genealogical species, called B. 'Austria', we found greatly enlarged genome sizes that could roughly be approximated as multiples of the genomes of its closest relatives, which suggests that whole-genome duplications have occurred early during separation of this lineage. Overall, genome size was significantly correlated to egg size and body size, even though the latter became non-significant after controlling for phylogenetic non-independence. Our study suggests that substantial genome size variation can build up early during speciation, potentially even among isolated populations. An alternative, but not mutually exclusive interpretation might be that reproductive isolation tends to build up unusually slow in this species complex.

The correlation between changes of C-reactive protein (CRP level and size of infarct in stroke

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Shahram Aboutalebi

2006-09-01

Full Text Available Background: The presence of C-reactive protein (CRP during different stages of stroke had been shown in several studies. There is still no definite document about the correlation of CRP level and size of infarct in stroke. We studied the correlation of the acute level of CRP with size of infarct in stroke. Methods: A total of 90 consecutive patients with acute stroke admitted in Fatemeh Zahra University Hospital in Bushehr city were studied. Levels of CRP were measured at admission time and 48 hours later. Sizes of infarct and types of stroke were determined with Computerized Tomography scanning. The excluded patients were those with infection, stroke in brain stem, a delay more than 24 hours after attack of stroke and Transient Ischemic Attacks. CRP level was measured quantitatively using ELISA method. Results: No correlation between the first CRP levels and variables of age, size of infarct and type of stroke was detected. Size of infarct was correlated with the second CRP (r=0.41, P<0.001 and the difference in CRP levels (r=0.45, P<0.001. The CRP difference was significant in ischemic, hemorrhagic and territory infarcts (P<0.01. But there was no difference between the first and the second CRP in lacunar infarcts. Conclusion: We found no correlation between the CRP levels of the 24 first hours after acute stroke with size of infarct in stroke. But the increase of CRP levels which were measured in 48 hours after the stroke had correlation with size of infarct irrespective of types of stroke. More studies could reveal the cause and effect of CRP in size of infarct in stroke.

Norms as Group-Level Constructs: Investigating School-Level Teen Pregnancy Norms and Behaviors.

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Mollborn, Stefanie; Domingue, Benjamin W; Boardman, Jason D

2014-09-01

Social norms are a group-level phenomenon, but past quantitative research has rarely measured them in the aggregate or considered their group-level properties. We used the school-based design of the National Longitudinal Study of Adolescent Health to measure normative climates regarding teen pregnancy across 75 U.S. high schools. We distinguished between the strength of a school's norm against teen pregnancy and the consensus around that norm. School-level norm strength and dissensus were strongly (r = -0.65) and moderately (r = 0.34) associated with pregnancy prevalence within schools, respectively. Normative climate partially accounted for observed racial differences in school pregnancy prevalence, but norms were a stronger predictor than racial composition. As hypothesized, schools with both a stronger average norm against teen pregnancy and greater consensus around the norm had the lowest pregnancy prevalence. Results highlight the importance of group-level normative processes and of considering the local school environment when designing policies to reduce teen pregnancy.

Effects of Stocking Density or Group Size on Intake, Growth, and Meat Quality of Hanwoo Steers (

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Sang Moo Lee

2012-11-01

Full Text Available This study was conducted to investigate the effects of stocking density or group size on feed intake, daily gain, and carcass characteristics of Hanwoo (Korean indigenous breed steers reared from 7 months to 31 months of age. Thirty Hanwoo steers were divided into four groups with three replicates each (a total of 12 pens. In each group, one (G1, two (G2, three (G3, and four steers (G4 per pen were allocated as treatments. Pen size was 32.0 m2, and therefore Hanwoo steers in G1, G2, G3, and G4 were reared under different space allowances, i.e. 32.0, 16.0, 10.6, and 8.0 m2/steer, respectively. Steers were reared following a conventional beef cattle management method in Korea, and were offered a fixed amount of commercial concentrate with ad libitum forages. Results were subjected to analysis of variance with stocking density as the main effect, and significance was declared at p<0.05. Although total feed intake was not significantly altered, it numerically increased in animals of low stocking density (G1 compared to those subjected to high stocking density treatment (i.e. G4. Feed conversion ratio was higher (p<0.05 in G3 compared to G1 and G2. Animals in G1 (low stocking density grew faster (p<0.05 than those of high stocking density (G3 and G4. Back fat thickness, meat yield index, and meat yield grade were similar among all levels of stocking density. However, longissimus muscle area was larger in G1 and G2 (p<0.01 compared to G3 and G4, and animals in G3 produced smaller carcasses (p<0.05. Carcass quality traits, including marbling score, meat color, fat color, texture, maturity and meat quality grade, as determined by a group of experts, were not significantly different among the treatments. In conclusion, lower stocking density resulted in increased feed efficiency, daily gain, and carcass weight in Hanwoo steers. However it remains unclear whether such differences are the results of stocking density or group size, or a combination of both

Body size satisfaction and physical activity levels among men and women.

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Kruger, Judy; Lee, Chong-Do; Ainsworth, Barbara E; Macera, Caroline A

2008-08-01

Body size satisfaction may be an important factor associated with physical activity. We analyzed data from the 2002 National Physical Activity and Weight Loss Survey (NPAWLS), a population-based cross-sectional telephone survey of US adults. Multiple logistic regression models were used to examine the association of body size satisfaction on being regularly active. Participants were aged > or =18 years with complete data on weight, race/ethnicity, physical activity level, and body size satisfaction (n = 10,021). More than half of men (55.8%) and women (53.3%) who reported being very satisfied with the body size were regularly active. After adjustment for covariates, participants who reported being somewhat or not satisfied with their body size had a 13 and 44% lower odds of being regularly active, respectively, compared with those very satisfied with their body size. When stratified by race/ethnicity, this association remained in whites (P for trend physical activity than those less satisfied. Further research is needed to explore predictors of physical activity to reduce health disparities.

Collective nostalgia: A group-level emotion that confers unique benefits on the group.

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Wildschut, Tim; Bruder, Martin; Robertson, Sara; van Tilburg, Wijnand A P; Sedikides, Constantine

2014-11-01

This research established collective nostalgia as a group-level emotion and ascertained the benefits it confers on the group. In Study 1, participants who reflected on a nostalgic event they had experienced together with ingroup members (collective nostalgia) evaluated the ingroup more positively and reported stronger intentions to approach (and not avoid) ingroup members than those who recalled a nostalgic event they had experienced individually (personal nostalgia), those who reflected on a lucky event they had experienced together with ingroup members (collective positive), and those who did not recall an event (no recall). In Study 2, collective (vs. personal) nostalgia strengthened behavioral intentions to support the ingroup more so than did recalling an ordinary collective (vs. personal) event. Increased collective self-esteem mediated this effect. In Study 3, collective nostalgia (compared with recall of an ordinary collective event) led participants to sacrifice money in order to punish a transgression perpetrated against an ingroup member. This effect of collective nostalgia was more pronounced when social identification was high (compared with low). Finally, in Study 4, collective nostalgia converged toward the group average (i.e., was socially shared) when participants thought of themselves in terms of their group membership. The findings underscore the viability of studying nostalgia at multiple levels of analysis and highlight the significance of collective nostalgia for understanding group-level attitudes, global action tendencies, specific behavioral intentions, and behavior.

An integrated approach for multi-level sample size determination

International Nuclear Information System (INIS)

Lu, M.S.; Teichmann, T.; Sanborn, J.B.

1997-01-01

Inspection procedures involving the sampling of items in a population often require steps of increasingly sensitive measurements, with correspondingly smaller sample sizes; these are referred to as multilevel sampling schemes. In the case of nuclear safeguards inspections verifying that there has been no diversion of Special Nuclear Material (SNM), these procedures have been examined often and increasingly complex algorithms have been developed to implement them. The aim in this paper is to provide an integrated approach, and, in so doing, to describe a systematic, consistent method that proceeds logically from level to level with increasing accuracy. The authors emphasize that the methods discussed are generally consistent with those presented in the references mentioned, and yield comparable results when the error models are the same. However, because of its systematic, integrated approach the proposed method elucidates the conceptual understanding of what goes on, and, in many cases, simplifies the calculations. In nuclear safeguards inspections, an important aspect of verifying nuclear items to detect any possible diversion of nuclear fissile materials is the sampling of such items at various levels of sensitivity. The first step usually is sampling by ''attributes'' involving measurements of relatively low accuracy, followed by further levels of sampling involving greater accuracy. This process is discussed in some detail in the references given; also, the nomenclature is described. Here, the authors outline a coordinated step-by-step procedure for achieving such multilevel sampling, and they develop the relationships between the accuracy of measurement and the sample size required at each stage, i.e., at the various levels. The logic of the underlying procedures is carefully elucidated; the calculations involved and their implications, are clearly described, and the process is put in a form that allows systematic generalization

Genome size evolution at the speciation level: The cryptic species complex Brachionus plicatilis (Rotifera

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Riss Simone

2011-04-01

Full Text Available Abstract Background Studies on genome size variation in animals are rarely done at lower taxonomic levels, e.g., slightly above/below the species level. Yet, such variation might provide important clues on the tempo and mode of genome size evolution. In this study we used the flow-cytometry method to study the evolution of genome size in the rotifer Brachionus plicatilis, a cryptic species complex consisting of at least 14 closely related species. Results We found an unexpectedly high variation in this species complex, with genome sizes ranging approximately seven-fold (haploid '1C' genome sizes: 0.056-0.416 pg. Most of this variation (67% could be ascribed to the major clades of the species complex, i.e. clades that are well separated according to most species definitions. However, we also found substantial variation (32% at lower taxonomic levels - within and among genealogical species - and, interestingly, among species pairs that are not completely reproductively isolated. In one genealogical species, called B. 'Austria', we found greatly enlarged genome sizes that could roughly be approximated as multiples of the genomes of its closest relatives, which suggests that whole-genome duplications have occurred early during separation of this lineage. Overall, genome size was significantly correlated to egg size and body size, even though the latter became non-significant after controlling for phylogenetic non-independence. Conclusions Our study suggests that substantial genome size variation can build up early during speciation, potentially even among isolated populations. An alternative, but not mutually exclusive interpretation might be that reproductive isolation tends to build up unusually slow in this species complex.

Hypoadiponectinemia, elevated iron and high-sensitivity C-reactive protein levels and their relation with prostate size in benign prostatic hyperplasia.

Science.gov (United States)

Nandeesha, H; Eldhose, A; Dorairajan, L N; Anandhi, B

2017-09-01

Elevated iron, high-sensitivity C-reactive protein (CRP) and hypoadiponectinemia are known to initiate tumour development. There is paucity of data regarding the above-mentioned parameters and their relation with prostate size in benign prostatic hyperplasia (BPH). The present study was designed to assess the levels of iron, hs-CRP and adiponectin levels and their association with prostate size in BPH patients. A total of 37 BPH cases and 36 controls were enrolled in the study. Iron, hs-CRP and adiponectin were estimated in both the groups. Iron and hs-CRP were significantly increased and adiponectin was significantly reduced in BPH cases when compared with controls. Iron (r = .397, p = .015), hs-CRP (r = .341, p = .039) and adiponectin (r = -.464, p = .004) were significantly associated with prostate size in BPH cases. Multivariate linear regression analysis showed that iron acts as predictor of prostate size in BPH (R 2  = 0.395, β = 0.526, p = .001). We conclude that iron and hs-CRP are elevated and adiponectin is reduced in BPH cases and associated with prostate size. © 2016 Blackwell Verlag GmbH.

Comparison of serum lead level in oral opium addicts with healthy control group.

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Salehi, Hossein; Sayadi, Ahmad Reza; Tashakori, Mahnaz; Yazdandoost, Rokhsareh; Soltanpoor, Narges; Sadeghi, Hossein; Aghaee-Afshar, Mahmood

2009-11-01

Drug abuse and its consequences are major health problems in Middle-East countries such as Iran. Salesmen and smugglers may add lead to opium during the process of opium preparation to increase the weight of opium for more profit. Several reports have found lead poisoning symptoms in opium addicted patients and there are many nonspecific symptoms mimicking lead poisoning in opium addicted patients. As far as the literature review is concerned, there is no comparative study about blood lead level (BLL) in addicted patients with healthy controls. Therefore, it seems evaluation of blood lead level in opium addicted patients to be important. In this study, the BLL of forty-four subjects in two patient and control groups was evaluated. The patient group (22 subjects) was comprised of patients who used oral opium. Control group (22 subjects) was matched with the patient group for age and sex, considering inclusion and exclusion criteria with a mean age of 38.8+/-6.7. For blood lead assay, 3 mL of whole blood was obtained from both groups by venipuncture and BLL was assessed immediately using an atomic absorption spectrophotometer. The BLL in patient group had a range of 7.2 to 69.9 g/dL with a mean of 21.9+/-13.2. In the healthy control group, BLL was between 4.1 to 17.4 g/dL with a mean of 8.6+/-3.5. The mean difference of both groups (t=4.56) was statistically significant (Popium ingested (r=0.65, Popium ingestion in the patient group. It would be concluded that opium addicts have an elevated BLL compared to healthy controls. Therefore, screening of blood lead concentration is helpful for opium addicted people especially with non-specific symptoms. In this regard, a similar investigation with a larger sample size of opium addicted patients (including both oral and inhaled) and a control group is suggested to confirm the findings of this research.

Does Ploidy Level Directly Control Cell Size? Counterevidence from Arabidopsis Genetics

OpenAIRE

Tsukaya, Hirokazu

2013-01-01

Ploidy level affects cell size in many organisms, and ploidy-dependent cell enlargement has been used to breed many useful organisms. However, how polyploidy affects cell size remains unknown. Previous studies have explored changes in transcriptome data caused by polyploidy, but have not been successful. The most naïve theory explaining ploidy-dependent cell enlargement is that increases in gene copy number increase the amount of protein, which in turn increases the cell volume. This hypothes...

Interteaching: The Effects of Discussion Group Size on Undergraduate Student Performance and Preference

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Gutierrez, Michael

2017-01-01

Interteaching is a college teaching method grounded in the principles of applied behavior analysis. Research on interteaching demonstrates that it improves academic performance, and students report greater satisfaction with interteaching as compared to traditional teaching styles. The current study investigates whether discussion group size, a…

Fish mercury levels in lakes - adjusting for Hg and fish-size covariation

International Nuclear Information System (INIS)

Sonesten, Lars

2003-01-01

Fish-size covariation can be circumvented by regression intercepts of Hg vs. fish length as lake-specific Hg levels. - Accurate estimates of lake-specific mercury levels are vital in assessing the environmental impact on the mercury content in fish. The intercepts of lake-specific regressions of Hg concentration in fish vs. fish length provide accurate estimates when there is a prominent Hg and fish-size covariation. Commonly used regression methods, such as analysis of covariance (ANCOVA) and various standardization techniques are less suitable, since they do not completely remove the fish-size covariation when regression slopes are not parallel. Partial least squares (PLS) regression analysis reveals that catchment area and water chemistry have the strongest influence on the Hg level in fish in circumneutral lakes. PLS is a multivariate projection method that allows biased linear regression analysis of multicollinear data. The method is applicable to statistical and visual exploration of large data sets, even if there are more variables than observations. Environmental descriptors have no significant impact on the slopes of linear regressions of the Hg concentration in perch (Perca fluviatilis L.) vs. fish length, suggesting that the slopes mainly reflect ontogenetic dietary shifts during the perch life span

Does Group-Level Commitment Predict Employee Well-Being?: A Prospective Analysis.

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Clausen, Thomas; Christensen, Karl Bang; Nielsen, Karina

2015-11-01

To investigate the links between group-level affective organizational commitment (AOC) and individual-level psychological well-being, self-reported sickness absence, and sleep disturbances. A total of 5085 care workers from 301 workgroups in the Danish eldercare services participated in both waves of the study (T1 [2005] and T2 [2006]). The three outcomes were analyzed using linear multilevel regression analysis, multilevel Poisson regression analysis, and multilevel logistic regression analysis, respectively. Group-level AOC (T1) significantly predicted individual-level psychological well-being, self-reported sickness absence, and sleep disturbances (T2). The association between group-level AOC (T1) and psychological well-being (T2) was fully mediated by individual-level AOC (T1), and the associations between group-level AOC (T1) and self-reported sickness absence and sleep disturbances (T2) were partially mediated by individual-level AOC (T1). Group-level AOC is an important predictor of employee well-being in contemporary health care organizations.

Size of age-0 crappies (Pomoxis spp.) relative to reservoir habitats and water levels

Science.gov (United States)

Kaczka, Levi J.; Miranda, Leandro E.

2014-01-01

Variable year-class strength is common in crappie Pomoxis spp. populations in many reservoirs, yet the mechanisms behind this variability are poorly understood. Size-dependent mortality of age-0 fishes has long been recognized in the population ecology literature; however, investigations about the effects of environmental factors on age-0 crappie size are lacking. The objective of this study was to determine if differences existed in total length of age-0 crappies between embayment and floodplain habitats in reservoirs, while accounting for potential confounding effects of water level and crappie species. To this end, we examined size of age-0 crappies in four flood-control reservoirs in northwest Mississippi over 4years. Age-0 crappies inhabiting uplake floodplain habitats grew to a larger size than fish in downlake embayments, but this trend depended on species, length of time a reservoir was dewatered in the months preceding spawning, and reservoir water level in the months following spawning. The results from our study indicate that water-level management may focus not only on allowing access to quality nursery habitat, but that alternating water levels on a multiyear schedule could increase the quality of degraded littoral habitats.

Use of care management practices in small- and medium-sized physician groups: do public reporting of physician quality and financial incentives matter?

Science.gov (United States)

Alexander, Jeffrey A; Maeng, Daniel; Casalino, Lawrence P; Rittenhouse, Diane

2013-04-01

To examine the effect of public reporting (PR) and financial incentives tied to quality performance on the use of care management practices (CMPs) among small- and medium-sized physician groups. Survey data from The National Study of Small and Medium-sized Physician Practices were used. Primary data collection was also conducted to assess community-level PR activities. The final sample included 643 practices engaged in quality reporting; about half of these practices were subject to PR. We used a treatment effects model. The instrumental variables were the community-level variables that capture the level of PR activity in each community in which the practices operate. (1) PR is associated with increased use of CMPs, but the estimate is not statistically significant; (2) financial incentives are associated with greater use of CMPs; (3) practices' awareness/sensitivity to quality reports is positively related to their use of CMPs; and (4) combined PR and financial incentives jointly affect CMP use to a greater degree than either of these factors alone. Small- to medium-sized practices appear to respond to PR and financial incentives by greater use of CMPs. Future research needs to investigate the appropriate mix and type of incentive arrangements and quality reporting. © Health Research and Educational Trust.

The Size of Local Government Administration at a Municipal Level as a Determinant of Entrepreneurship

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Rusłan Harasym

2017-01-01

Full Text Available This artcle’s aim is to examine a dependency between local government administraton at a municipal level and the level of local entrepreneurship. This paper atempts to answer the queston of whether the size of the local government administraton has features of stmulant or de-stmulant in the process of setng up a business. In other words, does the size of public administraton at a local level (municipal level have a positve or negatve impact on creatng new business enttes? This is important due to at least a couple of reasons. First of all, the current research achievements are not extensive, when it comes to the publicatons that link entrepreneurship and the size of local government administraton. Secondly, the problem of entrepreneurship determinants consttutes stll topical and not fully investgated (or explained aspects of local economy development. Thirdly and fnally, the authors of this artcle have proposed and copyrighted an approach to the quantfcaton of the size of local government administraton, modifying commonly used measures of local public administraton. Thus, this artcle fts not only into the explanaton of the entrepreneurship phenomenon and its determinants, but also contributes to the development of knowledge about dependencies between the size of local selfgovernment and the entrepreneurship level. It expands the knowledge resource on analyzed dependencies and re-orients current approaches to similar research.

SERUM PROLACTIN LEVEL IN ACNE PATIENTS VERSUS CONTROL GROUP: STUDY ON 14 TO 35 YEARS OLD WOMEN

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G FAGHIHI

2002-03-01

Full Text Available Introduction. Androgens have a main role in acne pathogenesis. The interaction between prolactin and androgens generate the hypothesis of prolactin role in acne pathogenesis. Methods. In a case - control study, 71 women with modearte to severe acne were compaired with 71 healthy women about their serum prolactin levels. Results. Mean of serum prolactin level was 533 632 miu/lit in cases. Mean of serum prolactin level was 365 363 in control group (P > 0.05. There was a significant correlation between serum prolactin level and severity of acne. Discussion. Despite the non significant difference between serum prolactin level in acne patients and healthy women, thare was a significant relationship between serum prolactin level and severity of acne. It may be due to our small sample size. However, the more powerful studies is needed.

The reduced local lymph node assay: the impact of group size.

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Ryan, Cindy A; Chaney, Joel G; Kern, Petra S; Patlewicz, Grace Y; Basketter, David A; Betts, Catherine J; Dearman, Rebecca J; Kimber, Ian; Gerberick, G Frank

2008-05-01

The local lymph node assay (LLNA) is a skin sensitization test that provides animal welfare benefits. To reduce animal usage further, a modified version (rLLNA) was proposed. Conducting the rLLNA as a screening test with a single high dose group and vehicle control differentiated accurately between skin sensitizers and non-sensitizers. This study examined whether a reduction in animal number/group is feasible. Historical data were utilized to examine the impact of conducting the rLLNA with two mice/group. To assess the effect on the stimulation index (SI) 41 datasets with individual animal data derived using five mice/group were analysed. SIs were calculated on all possible combinations of two control and two high dose group disintegrations per minute (dpm) values. For 25 of 33 sensitizer datasets, > 96% of possible dpm combinations resulted in a calculated SI > 3. The lowest percentages of positive SIs were observed with weak allergens when, in the standard LLNA, the mean SIs would have been nearer to the threshold value of 3. The results indicate that moderate, strong and extreme allergens are more likely than weak allergens to be identified as sensitizers when group sizes of two mice are used within the rLLNA. It is concluded that a rLLNA with two mice/group would display decreased sensitivity and is inappropriate for use in hazard identification. Copyright (c) 2007 John Wiley & Sons, Ltd.

Visual Acuity does not Moderate Effect Sizes of Higher-Level Cognitive Tasks

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Houston, James R.; Bennett, Ilana J.; Allen, Philip A.; Madden, David J.

2016-01-01

Background Declining visual capacities in older adults have been posited as a driving force behind adult age differences in higher-order cognitive functions (e.g., the “common cause” hypothesis of Lindenberger & Baltes, 1994). McGowan, Patterson and Jordan (2013) also found that a surprisingly large number of published cognitive aging studies failed to include adequate measures of visual acuity. However, a recent meta-analysis of three studies (LaFleur & Salthouse, 2014) failed to find evidence that visual acuity moderated or mediated age differences in higher-level cognitive processes. In order to provide a more extensive test of whether visual acuity moderates age differences in higher-level cognitive processes, we conducted a more extensive meta-analysis of topic. Methods Using results from 456 studies, we calculated effect sizes for the main effect of age across four cognitive domains (attention, executive function, memory, and perception/language) separately for five levels of visual acuity criteria (no criteria, undisclosed criteria, self-reported acuity, 20/80-20/31, and 20/30 or better). Results As expected, age had a significant effect on each cognitive domain. However, these age effects did not further differ as a function of visual acuity criteria. Conclusion The current meta-analytic, cross-sectional results suggest that visual acuity is not significantly related to age group differences in higher-level cognitive performance—thereby replicating LaFleur and Salthouse (2014). Further efforts are needed to determine whether other measures of visual functioning (e.g. contrast sensitivity, luminance) affect age differences in cognitive functioning. PMID:27070044

The use of 65Zn for estimating group size of brown hyaenas Hyaena ...

African Journals Online (AJOL)

MacDonald 1983), is influenced by the quality of resources within a territory (Mills 1982). Group size is, however, difficult to determine accurately using routine methods (i.e., direct counts and mark recapture techniques) owing to the shy, elusive and nocturnal habits of brown hyaenas and the physiognomic characteristics of ...

Size-regulated group separation of CoFe2O4 nanoparticles using centrifuge and their magnetic resonance contrast properties

Science.gov (United States)

Kang, Jongeun; Lee, Hyunseung; Kim, Young-Nam; Yeom, Areum; Jeong, Heejeong; Lim, Yong Taik; Hong, Kwan Soo

2013-09-01

Magnetic nanoparticle (MNP)-based magnetic resonance imaging (MRI) contrast agents (CAs) have been the subject of extensive research over recent decades. The particle size of MNPs varies widely and is known to influence their physicochemical and pharmacokinetic properties. There are two commonly used methods for synthesizing MNPs, organometallic and aqueous solution coprecipitation. The former has the advantage of being able to control the particle size more effectively; however, the resulting particles require a hydrophilic coating in order to be rendered water soluble. The MNPs produced using the latter method are intrinsically water soluble, but they have a relatively wide particle size distribution. Size-controlled water-soluble MNPs have great potential as MRI CAs and in cell sorting and labeling applications. In the present study, we synthesized CoFe2O4 MNPs using an aqueous solution coprecipitation method. The MNPs were subsequently separated into four groups depending on size, by the use of centrifugation at different speeds. The crystal shapes and size distributions of the particles in the four groups were measured and confirmed by transmission electron microscopy and dynamic light scattering. Using X-ray diffraction analysis, the MNPs were found to have an inverse spinel structure. Four MNP groups with well-selected semi-Gaussian-like diameter distributions were obtained, with measured T2 relaxivities ( r 2) at 4.7 T and room temperature in the range of 60 to 300 mM-1s-1, depending on the particle size. This size regulation method has great promise for applications that require homogeneous-sized MNPs made by an aqueous solution coprecipitation method. Any group of the CoFe2O4 MNPs could be used as initial base cores of MRI T2 CAs, with almost unique T2 relaxivity owing to size regulation. The methodology reported here opens up many possibilities for biosensing applications and disease diagnosis.

Mercury levels in defined Italian population groups

International Nuclear Information System (INIS)

Ingrao, G.; Belloni, P.

1992-01-01

The consumption of fish and seafood usually is the main source of intake of methylmercury for members of the general population. Therefore subjects having a diet rich in these food items present a high risk of exceeding the tolerable recommended weekly intake of mercury set by FAO and WHO. The average consumption of fish at a national level is rather small in Italy, 12.5 kg per year, consequently the risk of exposure to elevated levels of mercury through the diet for members of the Italian general population is rather negligible. However, fish is one of the main components of the diet of some population groups. These groups are usually found in coastal towns close fishing ports and include subjects working as fishermen, fish dealers, restaurant workers and their families. The purpose of this research programme, carried our with the collaboration of the National Institute of Nutrition is to determine the levels of mercury and methylmercury in hair samples of subjects having a higher than average fish consumption and to evaluate the effects of elevated intakes of mercury. 1 ref., 13 figs

Comparison of folic acid levels in schizophrenic patients and control groups

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Arthy, C. C.; Amin, M. M.; Effendy, E.

2018-03-01

Folic acid deficiency is a risk factor for schizophrenia through epidemiology, biochemistry and gene-related studies. Compared with healthy people, schizophrenic patients may have high homocysteine plasma values and homocysteine or low levels of folic acid, which seems to correlate with extrapyramidal motor symptoms caused by neuroleptic therapy and with symptoms of schizophrenia. In this present study, we focus on the difference of folic acid level between schizophrenic patient and control group. The study sample consisted of schizophrenic patients and 14 people in the control group and performed blood sampling to obtain the results of folic acid levels. The folic acid level in both groups was within normal range, but the schizophrenic patient group had lower mean folic acid values of 5.00 ng/ml (sb 1.66), compared with the control group with mean folic acid values of 10.75 ng/ml (sb 4.33). there was the group of the control group had a higher value of folic acid than the schizophrenic group.

Nest Digging by Leaf-Cutting Ants: Effect of Group Size and Functional Structures

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Roberto da Silva Camargo

2012-01-01

Full Text Available Leaf-cutting ant workers dig underground chambers, for housing their symbiotic fungus, interconnected by a vast quantity of tunnels whose function is to permit the entrance of food (leaves, gaseous exchanges, and movement of workers, offspring, and the queen. Digging is a task executed by a group of workers, but little is known about the group effect and group-constructed functional structures. Thus, we analyzed the structures formed by worker groups (5, 10, 20, and 40 individuals of the leaf-cutting ant, Atta sexdens rubropilosa, for 2 days of excavation. The digging arena was the same for the 4 groups, with each group corresponding to a different density. Our results verified a pattern of tunneling by the workers, but no chamber was constructed. The group effect is well known, since the 40-worker group dug significantly more than the groups of 5, 10, and 20. These groups did not differ statistically from each other. Analysis of load/worker verified that workers of the smallest group carried the greatest load. Our paper demonstrates the group effect on the digging of nests, namely, that excavation is proportional to group size, but without emergence of a functional structure such as a chamber.

[Geography of effective size of rural populations of Northern Eurasia. Geographic correlation between effective size and level of heterozygosity of populations].

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Evsiukov, A N; Zhukova, O V; Sheremet'eva, V A; Shneĭder, Iu V; Rychkov, Iu G

1996-11-01

A significant geographical correlation (r = 0.719) was found between the logarithm of effective size (InNe) and heterozygosity level (H) in populations under the assumption of the Hardy-Weinberg equilibrium. The area of highest positive correlation was positioned meridionally between the Ob and Yenisei rivers, from the Arctic coast of Taimyr Peninsula to eastern Sayans and the southern Cis-Baikal region, i.e., in the same region where the highest distribution density of mean Ne values was found. Two additional areas of high correlations were found on the northern Black Sea coast and in the lower Lena river region. Analysis and mapping of correlation ratios eta H/lnNe2 and eta lnNe/H2 revealed that effective size substantially influenced heterozygosity level (as could be expected in the case of an intense gene drift), and heterozygosity level influenced effective size to the same extent. The latter relationship indicated an intense adaptation, and changes in diversity of the gene pool caused substantial demographic changes. However, this might be accounted for by direct gene migration into a population prevailing over reverse migration, i.e., mechanical population growth prevailing over natural growth.

Preoperative TSH level and risk of thyroid cancer in patients with nodular thyroid disease: nodule size contribution.

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Zafón, Carles; Obiols, Gabriel; Mesa, Jordi

2015-01-01

Many reports have supported the relationship between high preoperative TSH levels and risk of thyroid cancer in nodular thyroid disease (NTD). We investigated whether TSH levels are related to the risk of differentiated thyroid carcinoma (DTC) in patients who have undergone total thyroidectomy for NTD. The relationship between TSH and size of malignant nodule was investigated. Finally, we assessed whether TSH levels are related to DTC and presence of additional benign nodules. A retrospective study of 980 patients was conducted. Variables included age at diagnosis, TSH level, nodule size, gender, final histology (benign versus DTC), and type of malignancy. Malignancy was present in 261 (26.6%) patients. These patients had higher median TSH levels as compared to those with no malignancy (1.61 mU/L (0.9-2.5) versus 0.9 mU/L (0.3-1.6); p-value<0.001). TSH was higher in patients with DTC in whom the largest nodule was malignant than in patients in whom the largest nodule was benign (1.80 mU/L (1.1-2.6) versus 1.38 mU/L (0.7-2.1) respectively; p-value=0.025). A significant correlation was seen between malignant nodule size and TSH level, but not between TSH levels and size of the largest benign nodule. Our study supported an association between preoperative TSH levels and risk of DTC in patients with NTD. There was also a direct relationship between malignant nodule size and TSH levels. By contrast, no relationship was found between the size of benign nodules and TSH levels. Copyright © 2014 SEEN. Published by Elsevier Espana. All rights reserved.

Vitamin D Levels in Different Severity Groups of Schizophrenia.

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Akinlade, Kehinde Sola; Olaniyan, Oyejide Afolabi; Lasebikan, Victor Olufolahan; Rahamon, Sheu Kadiri

2017-01-01

Vitamin D deficiency (VDD) continues to be associated with schizophrenia, but there is the dearth of information on the relationship between the severity of schizophrenia and plasma levels of vitamin D. This study, therefore, determined the plasma levels of vitamin D in different severity groups of schizophrenia. Plasma level of vitamin D was determined in 60 patients with schizophrenia and 30 apparently healthy individuals who served as controls. Patients with schizophrenia were classified into mildly ill, moderately ill, markedly ill, and severely ill groups using the Positive and Negative Syndrome Scale (PANSS). The mean level of vitamin D was significantly lower in patients with schizophrenia compared with the controls. Similarly, there was a significant association between VDD and schizophrenia. The mean plasma levels of vitamin D were not significantly different when the mildly, moderately, markedly, and severely ill groups were compared with one another and there was no significant correlation between vitamin D level and PANSS scores. Furthermore, patients on atypical antipsychotics had an insignificantly lower level of vitamin D compared with the patients on typical antipsychotics. It could be concluded from this study that patients with schizophrenia have low plasma vitamin D level which does not appear to be associated with the severity of schizophrenia and type of antipsychotics. Therefore, regular screening for vitamin D status of patients with schizophrenia is suggested in order to allow for the institution of appropriate clinical intervention when necessary.

Vitamin D Levels in Different Severity Groups of Schizophrenia

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Kehinde Sola Akinlade

2017-06-01

Full Text Available BackgroundVitamin D deficiency (VDD continues to be associated with schizophrenia, but there is the dearth of information on the relationship between the severity of schizophrenia and plasma levels of vitamin D. This study, therefore, determined the plasma levels of vitamin D in different severity groups of schizophrenia.Materials and methodsPlasma level of vitamin D was determined in 60 patients with schizophrenia and 30 apparently healthy individuals who served as controls. Patients with schizophrenia were classified into mildly ill, moderately ill, markedly ill, and severely ill groups using the Positive and Negative Syndrome Scale (PANSS.ResultsThe mean level of vitamin D was significantly lower in patients with schizophrenia compared with the controls. Similarly, there was a significant association between VDD and schizophrenia. The mean plasma levels of vitamin D were not significantly different when the mildly, moderately, markedly, and severely ill groups were compared with one another and there was no significant correlation between vitamin D level and PANSS scores. Furthermore, patients on atypical antipsychotics had an insignificantly lower level of vitamin D compared with the patients on typical antipsychotics.ConclusionIt could be concluded from this study that patients with schizophrenia have low plasma vitamin D level which does not appear to be associated with the severity of schizophrenia and type of antipsychotics. Therefore, regular screening for vitamin D status of patients with schizophrenia is suggested in order to allow for the institution of appropriate clinical intervention when necessary.

12 CFR 1282.18 - Affordability-Income level definitions-family size not known (actual or prospective tenants).

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2010-01-01

....18 Affordability—Income level definitions—family size not known (actual or prospective tenants). In... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Affordability-Income level definitions-family size not known (actual or prospective tenants). 1282.18 Section 1282.18 Banks and Banking FEDERAL...

Small renal size in newborns with spina bifida: possible causes.

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Montaldo, Paolo; Montaldo, Luisa; Iossa, Azzurra Concetta; Cennamo, Marina; Caredda, Elisabetta; Del Gado, Roberto

2014-02-01

Previous studies reported that children with neural tube defects, but without any history of intrinsic renal diseases, have small kidneys when compared with age-matched standard renal growth. The aim of this study was to investigate the possible causes of small renal size in children with spina bifida by comparing growth hormone deficiency, physical limitations and hyperhomocysteinemia. The sample included 187 newborns with spina bifida. Renal sizes in the patients were assessed by using maximum measurement of renal length and the measurements were compared by using the Sutherland monogram. According to the results, the sample was divided into two groups--a group of 120 patients with small kidneys (under the third percentile) and a control group of 67 newborns with normal kidney size. Plasma total homocysteine was investigated in mothers and in their children. Serum insulin-like growth factor-1 (IGF-1) levels were measured. Serum IGF-1 levels were normal in both groups. Children and mothers with homocysteine levels >10 μmol/l were more than twice as likely to have small kidneys and to give to birth children with small kidneys, respectively, compared with newborns and mothers with homocysteine levels <10 μmol/l. An inverse correlation was also found between the homocysteine levels of mothers and kidney sizes of children (r = - 0.6109 P ≤ 0.01). It is highly important for mothers with hyperhomocysteinemia to be educated about benefits of folate supplementation in order to reduce the risk of small renal size and lower renal function in children.

Influence of prey dispersion on territory and group size of African lions: a test of the resource dispersion hypothesis.

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Valeix, Marion; Loveridge, Andrew J; MacDonald, David W

2012-11-01

Empirical tests of the resource dispersion hypothesis (RDH), a theory to explain group living based on resource heterogeneity, have been complicated by the fact that resource patch dispersion and richness have proved difficult to define and measure in natural systems. Here, we studied the ecology of African lions Panthera leo in Hwange National Park, Zimbabwe, where waterholes are prey hotspots, and where dispersion of water sources and abundance of prey at these water sources are quantifiable. We combined a 10-year data set from GPS-collared lions for which information of group composition was available concurrently with data for herbivore abundance at waterholes. The distance between two neighboring waterholes was a strong determinant of lion home range size, which provides strong support for the RDH prediction that territory size increases as resource patches are more dispersed in the landscape. The mean number of herbivore herds using a waterhole, a good proxy of patch richness, determined the maximum lion group biomass an area can support. This finding suggests that patch richness sets a maximum ceiling on lion group size. This study demonstrates that landscape ecology is a major driver of ranging behavior and suggests that aspects of resource dispersion limit group sizes.

24 CFR 81.18 - Affordability-Income level definitions-family size not known (actual or prospective tenants).

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2010-04-01

... definitions-family size not known (actual or prospective tenants). 81.18 Section 81.18 Housing and Urban... CORPORATION (FREDDIE MAC) Housing Goals § 81.18 Affordability—Income level definitions—family size not known... moderate-income families where family size is not known to the GSE, income will be adjusted using unit size...

Effects of reproductive status, social rank, sex and group size on vigilance patterns in Przewalski's gazelle.

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Chunlin Li

Full Text Available Quantifying vigilance and exploring the underlying mechanisms has been the subject of numerous studies. Less attention has focused on the complex interplay between contributing factors such as reproductive status, social rank, sex and group size. Reproductive status and social rank are of particular interest due to their association with mating behavior. Mating activities in rutting season may interfere with typical patterns of vigilance and possibly interact with social rank. In addition, balancing the tradeoff between vigilance and life maintenance may represent a challenge for gregarious ungulate species rutting under harsh winter conditions. We studied vigilance patterns in the endangered Przewalski's gazelle (Procapra przewalskii during both the rutting and non-rutting seasons to examine these issues.Field observations were carried out with focal sampling during rutting and non-rutting season in 2008-2009. Results indicated a complex interplay between reproductive status, social rank, sex and group size in determining vigilance in this species. Vigilance decreased with group size in female but not in male gazelles. Males scanned more frequently and thus spent more time vigilant than females. Compared to non-rutting season, gazelles increased time spent scanning at the expense of bedding in rutting season. During the rutting season, territorial males spent a large proportion of time on rutting activities and were less vigilant than non-territorial males. Although territorial males may share collective risk detection with harem females, we suggest that they are probably more vulnerable to predation because they seemed reluctant to leave rut stands under threats.Vigilance behavior in Przewalski's gazelle was significantly affected by reproductive status, social rank, sex, group size and their complex interactions. These findings shed light on the mechanisms underlying vigilance patterns and the tradeoff between vigilance and other crucial

The relationship between group size, intoxication and continuing to drink after bar attendance.

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Reed, Mark B; Clapp, John D; Martell, Brandi; Hidalgo-Sotelo, Alexandra

2013-11-01

The present study was undertaken to explore multilevel determinants of planning to continue to drink alcohol after leaving public drinking events. We assessed whether individual-level factors, group-related factors, or event-level bar characteristics were associated with post-bar drinking. We recruited a total of 642 participants from 30 participating bars in urban Southern California. Groups who arrived to patron a bar were interviewed upon their entrance and exit. Given data nesting, we employed a multilevel modeling approach to data analysis. More than one-third (40%) of our sample reported the intention to continue drinking as they exited the bar. Results of our multilevel model indicated eight individual-level variables significantly associated with intending to continue to drink. Time of night moderated the relationship between BrAC change and intentions to continue to drink. Although none of the group factors were significant in our model, a significant cross-level interaction between BrAC change and number of group members indicated the effect of intoxication on planning to continue to drink increases as group members increase. At the bar level, the presence of temporary bars and server offers of non-alcoholic drinks significantly decreased intentions to continue to drink. Given the large percentage of participants who reported the intention to continue drinking after exiting a bar, this study draws attention to the fact that field studies of drinking behavior may assess drinking mid-event rather than at the end of a drinking event. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Nuclear size is sensitive to NTF2 protein levels in a manner dependent on Ran binding

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Vuković, Lidija D.; Jevtić, Predrag; Zhang, Zhaojie; Stohr, Bradley A.; Levy, Daniel L.

2016-01-01

ABSTRACT Altered nuclear size is associated with many cancers, and determining whether cancer-associated changes in nuclear size contribute to carcinogenesis necessitates an understanding of mechanisms of nuclear size regulation. Although nuclear import rates generally positively correlate with nuclear size, NTF2 levels negatively affect nuclear size, despite the role of NTF2 (also known as NUTF2) in nuclear recycling of the import factor Ran. We show that binding of Ran to NTF2 is required for NTF2 to inhibit nuclear expansion and import of large cargo molecules in Xenopus laevis egg and embryo extracts, consistent with our observation that NTF2 reduces the diameter of the nuclear pore complex (NPC) in a Ran-binding-dependent manner. Furthermore, we demonstrate that ectopic NTF2 expression in Xenopus embryos and mammalian tissue culture cells alters nuclear size. Finally, we show that increases in nuclear size during melanoma progression correlate with reduced NTF2 expression, and increasing NTF2 levels in melanoma cells is sufficient to reduce nuclear size. These results show a conserved capacity for NTF2 to impact on nuclear size, and we propose that NTF2 might be a new cancer biomarker. PMID:26823604

Long-term resource variation and group size: A large-sample field test of the Resource Dispersion Hypothesis

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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.

High circulating osteoprotegerin levels are associated with non-zero blood groups.

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Nagy, Elod Erno; Varga-Fekete, Timea; Puskas, Attila; Kelemen, Piroska; Brassai, Zoltan; Szekeres-Csiki, Katalin; Gombos, Timea; Csanyi, Maria Csilla; Harsfalvi, Jolan

2016-05-26

Osteoprotegerin (OPG) and von Willebrand factor (VWF) form complex within endothelial cells and following secretion. The nature of blood group antigens strongly influences the levels of circulating VWF, but there is no available data concerning its ascendancy on OPG levels. We aimed to assess the relationship of AB0 blood groups with OPG, VWF levels (VWF: Ag) and collagen binding activity (VWF: CB) in peripheral arterial disease (PAD) patients. Functional and laboratory parameters of 105 PAD patients and 109 controls were examined. Results of OPG, VWF: Ag, VWF: CB (ELISA-s) were analysed by comparative statistics, together with clinical data. OPG levels were higher in patients than in controls (4.64 ng/mL vs. 3.68 ng/mL, p blood groups compared to 0-groups both in patients and controls (4.95 ng/mL vs. 3.90 ng/mL, p = 0.012 and 4.09 ng/mL vs. 3.40 ng/mL, p = 0.002). OPG levels are associated to blood group phenotypes and higher in non-0 individuals. Increased OPG levels in PAD characterize disease severity. The significant correlation between OPG and VWF:CB might have functional importance in an atherothrombosis-prone biological environment.

The effect of peer-group size on the delivery of feedback in basic life support refresher training: a cluster randomized controlled trial.

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Cho, Youngsuk; Je, Sangmo; Yoon, Yoo Sang; Roh, Hye Rin; Chang, Chulho; Kang, Hyunggoo; Lim, Taeho

2016-07-04

Students are largely providing feedback to one another when instructor facilitates peer feedback rather than teaching in group training. The number of students in a group affect the learning of students in the group training. We aimed to investigate whether a larger group size increases students' test scores on a post-training test with peer feedback facilitated by instructor after video-guided basic life support (BLS) refresher training. Students' one-rescuer adult BLS skills were assessed by a 2-min checklist-based test 1 year after the initial training. A cluster randomized controlled trial was conducted to evaluate the effect of student number in a group on BLS refresher training. Participants included 115 final-year medical students undergoing their emergency medicine clerkship. The median number of students was 8 in the large groups and 4 in the standard group. The primary outcome was to examine group differences in post-training test scores after video-guided BLS training. Secondary outcomes included the feedback time, number of feedback topics, and results of end-of-training evaluation questionnaires. Scores on the post-training test increased over three consecutive tests with instructor-led peer feedback, but not differ between large and standard groups. The feedback time was longer and number of feedback topics generated by students were higher in standard groups compared to large groups on the first and second tests. The end-of-training questionnaire revealed that the students in large groups preferred the smaller group size compared to their actual group size. In this BLS refresher training, the instructor-led group feedback increased the test score after tutorial video-guided BLS learning, irrespective of the group size. A smaller group size allowed more participations in peer feedback.

Effect of Group-Selection Opening Size on Breeding Bird Habitat Use in a Bottomland Forest

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Moorman, C.E.; D.C. Guynn, Jr.

2001-12-01

Research on the effects of creating group-selection openings of various sizes on breeding birds habitat use in a bottomland hardwood forest of the Upper Coastal Plain of South Carolina. Creation of 0.5-ha group selection openings in southern bottomland forests should provide breeding habitat for some field-edge species in gaps and habitat for forest-interior species and canopy-dwelling forest-edge species between gaps provided that enough mature forest is made available.

The Impact of Group Size on Welfare Indicators of Ewes during Pregnancy

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Averós, Xavier; Beltrán de Heredia, Ignacia; Ruiz, Roberto; Estevez, Inma

2016-01-01

Group size (GS) and space allowance have major implications for the welfare of production species, however their effects are often confounded. In a previous study we investigated the impact of varying space allowance at constant GS. In the present work we report the consequences of varying GS on pregnant ewes while controlling space allowance. We housed ewes at 6 (GS6) or 12 ewes/enclosure (GS12), while controlling space allowance to 1.5 m2/ewe (3 enclosures/treatment), and necessarily varying enclosure size. Therefore, when indicating GS effects we implicitly reflect a confounding effect with that of enclosure size. Movement, use of space, behaviour, serum cortisol concentration and body condition score (BCS) were collected during the last 12 gestation weeks. Movement, use of space, and behaviour were collected every other week, during 2 days/week, using 10 minute continuous scan samplings. Blood was collected during weeks 10, 13, 17, and 21 of gestation, and BCS during weeks 15 and 21. Data were analysed using repeated measures, generalized linear mixed models, with GS, week, and their interaction as fixed effects, and enclosure as random effect. GS mainly affected movement and use of space. GS12 ewes walked longer distances using longer steps (Pewe is given during gestation, larger GS will result in larger effective space, and no major implications for the welfare of ewes should be expected as GS increases. Ewes will adapt their movement patterns and use of space to enclosure size, and no further behavioural, physiological and physical consequences should be expected. PMID:27893817

Variation in levels of reactive oxygen species is explained by maternal identity, sex and body-size-corrected clutch size in a lizard

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Olsson, Mats; Wilson, Mark; Uller, Tobias; Mott, Beth; Isaksson, Caroline

2009-01-01

Many organisms show differences between males and females in growth rate and crucial life history parameters, such as longevity. Considering this, we may expect levels of toxic metabolic by-products of the respiratory chain, such as reactive oxygen species (ROS), to vary with age and sex. Here, we analyse ROS levels in female Australian painted dragon lizards ( Ctenophorus pictus) and their offspring using fluorescent probes and flow cytometry. Basal level of four ROS species (singlet oxygen, peroxynitrite, superoxide and H2O2) measured with a combined marker, and superoxide measured specifically, varied significantly among families but not between the sexes. When blood cells from offspring were chemically encouraged to accelerate the electron transport chain by mitochondrial uncoupling, net superoxide levels were three times higher in daughters than sons (resulting in levels outside of the normal ROS range) and varied among mothers depending on offspring sex (significant interaction between maternal identity and offspring sex). In offspring, there were depressive effects on ROS of size-controlled relative clutch size, which relies directly on circulating levels of vitellogenin, a confirmed antioxidant in some species. Thus, levels of reactive oxygen species varies among females, offspring and in relation to reproductive investment in a manner that makes its regulatory processes likely targets of selection.

Analyzing indirect effects in cluster randomized trials. The effect of estimation method, number of groups and group sizes on accuracy and power.

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Joop eHox

2014-02-01

Full Text Available Cluster randomized trials assess the effect of an intervention that is carried out at the group or cluster level. Ajzen’s theory of planned behaviour is often used to model the effect of the intervention as an indirect effect mediated in turn by attitude, norms and behavioural intention. Structural equation modelling (SEM is the technique of choice to estimate indirect effects and their significance. However, this is a large sample technique, and its application in a cluster randomized trial assumes a relatively large number of clusters. In practice, the number of clusters in these studies tends to be relatively small, e.g. much less than fifty. This study uses simulation methods to find the lowest number of clusters needed when multilevel SEM is used to estimate the indirect effect. Maximum likelihood estimation is compared to Bayesian analysis, with the central quality criteria being accuracy of the point estimate and the confidence interval. We also investigate the power of the test for the indirect effect. We conclude that Bayes estimation works well with much smaller cluster level sample sizes such as 20 cases than maximum likelihood estimation; although the bias is larger the coverage is much better. When only 5 to 10 clusters are available per treatment condition even with Bayesian estimation problems occur.

Key Informant Models for Measuring Group-Level Variables in Small Groups: Application to Plural Subject Theory

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Algesheimer, René; Bagozzi, Richard P.; Dholakia, Utpal M.

2018-01-01

We offer a new conceptualization and measurement models for constructs at the group-level of analysis in small group research. The conceptualization starts with classical notions of group behavior proposed by Tönnies, Simmel, and Weber and then draws upon plural subject theory by philosophers Gilbert and Tuomela to frame a new perspective…

Climate change affects low trophic level marine consumers: warming decreases copepod size and abundance.

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Garzke, Jessica; Ismar, Stefanie M H; Sommer, Ulrich

2015-03-01

Concern about climate change has re-ignited interest in universal ecological responses to temperature variations: (1) biogeographical shifts, (2) phenology changes, and (3) size shifts. In this study we used copepods as model organisms to study size responses to temperature because of their central role in the pelagic food web and because of the ontogenetic length constancy between molts, which facilitates the definition of size of distinct developmental stages. In order to test the expected temperature-induced shifts towards smaller body size and lower abundances under warming conditions, a mesocosm experiment using plankton from the Baltic Sea at three temperature levels (ambient, ambient +4 °C, ambient -4 °C) was performed in summer 2010. Overall copepod and copepodit abundances, copepod size at all life stages, and adult copepod size in particular, showed significant temperature effects. As expected, zooplankton peak abundance was lower in warm than in ambient treatments. Copepod size-at-immature stage significantly increased in cold treatments, while adult size significantly decreased in warm treatments.

Item Response Theory at Subject- and Group-Level. Research Report 90-1.

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Tobi, Hilde

This paper reviews the literature about item response models for the subject level and aggregated level (group level). Group-level item response models (IRMs) are used in the United States in large-scale assessment programs such as the National Assessment of Educational Progress and the California Assessment Program. In the Netherlands, these…

Fractal multi-level organisation of human groups in a virtual world

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Fuchs, Benedikt; Sornette, Didier; Thurner, Stefan

2014-10-01

Humans are fundamentally social. They form societies which consist of hierarchically layered nested groups of various quality, size, and structure. The anthropologic literature has classified these groups as support cliques, sympathy groups, bands, cognitive groups, tribes, linguistic groups, and so on. Anthropologic data show that, on average, each group consists of approximately three subgroups. However, a general understanding of the structural dependence of groups at different layers is largely missing. We extend these early findings to a very large high-precision large-scale internet-based social network data. We analyse the organisational structure of a complete, multi-relational, large social multiplex network of a human society consisting of about 400,000 odd players of an open-ended massive multiplayer online game for which we know all about their various group memberships at different layers. Remarkably, the online players' society exhibits the same type of structured hierarchical layers as found in hunter-gatherer societies. Our findings suggest that the hierarchical organisation of human society is deeply nested in human psychology.

Lipoprotein(a) levels, apo(a) isoform size, and coronary heart disease risk in the Framingham Offspring Study

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The aim of this study was to assess the independent contributions of plasma levels of lipoprotein(a) [Lp(a)], Lp(a) cholesterol, and of apo(a) isoform size to prospective coronary heart disease (CHD) risk. Plasma Lp(a) and Lp(a) cholesterol levels, and apo(a) isoform size were measured at examinati...

Defensive responses by a social caterpillar are tailored to different predators and change with larval instar and group size

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McClure, Melanie; Despland, Emma

2011-05-01

Gregariousness in animals is widely accepted as a behavioral adaptation for protection from predation. However, predation risk and the effectiveness of a prey's defense can be a function of several other factors, including predator species and prey size or age. The objective of this study was to determine if the gregarious habit of Malacosoma disstria caterpillars is advantageous against invertebrate natural enemies, and whether it is through dilution or cooperative defenses. We also examined the effects of larval growth and group size on the rate and success of attacks. Caterpillars of M. disstria responded with predator-specific behaviors, which led to increased survival. Evasive behaviors were used against stinkbugs, while thrashing by fourth instar caterpillars and holding on to the silk mat by second instar caterpillars was most efficient against spider attacks. Collective head flicking and biting by groups of both second and fourth instar caterpillars were observed when attacked by parasitoids. Increased larval size decreased the average number of attacks by spiders but increased the number of attacks by both stinkbugs and parasitoids. However, increased body size decreased the success rate of attacks by all three natural enemies and increased handling time for both predators. Larger group sizes did not influence the number of attacks from predators but increased the number of attacks and the number of successful attacks from parasitoids. In all cases, individual risk was lower in larger groups. Caterpillars showed collective defenses against parasitoids but not against the walking predators. These results show that caterpillars use different tactics against different natural enemies. Overall, these tactics are both more diverse and more effective in fourth instar than in second instar caterpillars, confirming that growth reduces predation risk. We also show that grouping benefits caterpillars through dilution of risk, and, in the case of parasitoids, through

Mercury levels in defined population groups

International Nuclear Information System (INIS)

Ingrao, G.; Belloni, P.; Santaroni, G.P.

1995-01-01

Hair samples from subjects living in the areas of Bagnara Calabra, Fiumicino and Ravenna, having a fish consumption above the national average, have been analyzed. A new location close to the Lagoon of Grado and Marano, located near the border with Slovenia, has been Selected because of the high natural levels of mercury in this lagoon due to the discharge of the Isonzo river, a tributary of which crosses the mercury rich area of Idria in Slovenia. During the last year, a group of pregnant women were selected in Rome, Bagnara Calabra, Ravenna and the area of the Lagoon of Grado and Marano. Samples of hair, pubic hair and placenta were collected from each of the subjects. A sample of the newborn hair was also collected whenever possible. The preliminary results indicate higher mercury levels in the subjects living in the area around the Lagoon of Grado and Marano. (author)

Mid-level perceptual features distinguish objects of different real-world sizes.

Science.gov (United States)

Long, Bria; Konkle, Talia; Cohen, Michael A; Alvarez, George A

2016-01-01

Understanding how perceptual and conceptual representations are connected is a fundamental goal of cognitive science. Here, we focus on a broad conceptual distinction that constrains how we interact with objects--real-world size. Although there appear to be clear perceptual correlates for basic-level categories (apples look like other apples, oranges look like other oranges), the perceptual correlates of broader categorical distinctions are largely unexplored, i.e., do small objects look like other small objects? Because there are many kinds of small objects (e.g., cups, keys), there may be no reliable perceptual features that distinguish them from big objects (e.g., cars, tables). Contrary to this intuition, we demonstrated that big and small objects have reliable perceptual differences that can be extracted by early stages of visual processing. In a series of visual search studies, participants found target objects faster when the distractor objects differed in real-world size. These results held when we broadly sampled big and small objects, when we controlled for low-level features and image statistics, and when we reduced objects to texforms--unrecognizable textures that loosely preserve an object's form. However, this effect was absent when we used more basic textures. These results demonstrate that big and small objects have reliably different mid-level perceptual features, and suggest that early perceptual information about broad-category membership may influence downstream object perception, recognition, and categorization processes. (c) 2015 APA, all rights reserved).

Effects of Group Size and Lack of Sphericity on the Recovery of Clusters in K-Means Cluster Analysis

Science.gov (United States)

de Craen, Saskia; Commandeur, Jacques J. F.; Frank, Laurence E.; Heiser, Willem J.

2006-01-01

K-means cluster analysis is known for its tendency to produce spherical and equally sized clusters. To assess the magnitude of these effects, a simulation study was conducted, in which populations were created with varying departures from sphericity and group sizes. An analysis of the recovery of clusters in the samples taken from these…

The role of host traits, season and group size on parasite burdens in a cooperative mammal.

Directory of Open Access Journals (Sweden)

Hermien Viljoen

Full Text Available The distribution of parasites among hosts is often characterised by a high degree of heterogeneity with a small number of hosts harbouring the majority of parasites. Such patterns of aggregation have been linked to variation in host exposure and susceptibility as well as parasite traits and environmental factors. Host exposure and susceptibility may differ with sexes, reproductive effort and group size. Furthermore, environmental factors may affect both the host and parasite directly and contribute to temporal heterogeneities in parasite loads. We investigated the contributions of host and parasite traits as well as season on parasite loads in highveld mole-rats (Cryptomys hottentotus pretoriae. This cooperative breeder exhibits a reproductive division of labour and animals live in colonies of varying sizes that procreate seasonally. Mole-rats were parasitised by lice, mites, cestodes and nematodes with mites (Androlaelaps sp. and cestodes (Mathevotaenia sp. being the dominant ecto- and endoparasites, respectively. Sex and reproductive status contributed little to the observed parasite prevalence and abundances possibly as a result of the shared burrow system. Clear seasonal patterns of parasite prevalence and abundance emerged with peaks in summer for mites and in winter for cestodes. Group size correlated negatively with mite abundance while it had no effect on cestode burdens and group membership affected infestation with both parasites. We propose that the mode of transmission as well as social factors constrain parasite propagation generating parasite patterns deviating from those commonly predicted.

The Class Size Question: A Study at Different Levels of Analysis. ACER Research Monograph No. 26.

Science.gov (United States)

Larkin, Anthony I.; Keeves, John P.

The purpose of this investigation was to examine the ways in which class size affected other facets of the educational environment of the classroom. The study focused on the commonly found positive relationship between class size and achievement. The most plausible explanation of the evidence seems to involve the effects of grouping more able…

24 CFR 81.17 - Affordability-Income level definitions-family size and income known (owner-occupied units, actual...

Science.gov (United States)

2010-04-01

... definitions-family size and income known (owner-occupied units, actual tenants, and prospective tenants). 81...—Income level definitions—family size and income known (owner-occupied units, actual tenants, and...-income families, where the unit is owner-occupied or, for rental housing, family size and income...

Development of an online database of typical food portion sizes in Irish population groups.

Science.gov (United States)

Lyons, Jacqueline; Walton, Janette; Flynn, Albert

2013-01-01

The Irish Food Portion Sizes Database (available at www.iuna.net) describes typical portion weights for an extensive range of foods and beverages for Irish children, adolescents and adults. The present paper describes the methodologies used to develop the database and some key characteristics of the portion weight data contained therein. The data are derived from three large, cross-sectional food consumption surveys carried out in Ireland over the last decade: the National Children's Food Survey (2003-2004), National Teens' Food Survey (2005-2006) and National Adult Nutrition Survey (2008-2010). Median, 25th and 75th percentile portion weights are described for a total of 545 items across the three survey groups, split by age group or sex as appropriate. The typical (median) portion weights reported for adolescents and adults are similar for many foods, while those reported for children are notably smaller. Adolescent and adult males generally consume larger portions than their female counterparts, though similar portion weights may be consumed where foods are packaged in unit amounts (for example, pots of yoghurt). The inclusion of energy under-reporters makes little difference to the estimation of typical portion weights in adults. The data have wide-ranging applications in dietary assessment and food labelling, and will serve as a useful reference against which to compare future portion size data from the Irish population. The present paper provides a useful context for researchers and others wishing to use the Irish Food Portion Sizes Database, and may guide researchers in other countries in establishing similar databases of their own.

A Size-based Ecosystem Model

DEFF Research Database (Denmark)

Ravn-Jonsen, Lars

 Ecosystem Management requires models that can link the ecosystem level to the operation level. This link can be created by an ecosystem production model. Because the function of the individual fish in the marine ecosystem, seen in trophic context, is closely related to its size, the model groups...... fish according to size. The model summarises individual predation events into ecosystem level properties, and thereby uses the law of conversation of mass as a framework. This paper provides the background, the conceptual model, basic assumptions, integration of fishing activities, mathematical...... the predator--prey interaction, (ii) mass balance in the predator--prey allocation, and (iii) mortality and somatic growth as a consequence of the predator--prey allocation. By incorporating additional assumptions, the model can be extended to other dimensions of the ecosystem, for example, space or species...

An Automatic User Grouping Model for a Group Recommender System in Location-Based Social Networks

Directory of Open Access Journals (Sweden)

Elahe Khazaei

2018-02-01

Full Text Available Spatial group recommendation refers to suggesting places to a given set of users. In a group recommender system, members of a group should have similar preferences in order to increase the level of satisfaction. Location-based social networks (LBSNs provide rich content, such as user interactions and location/event descriptions, which can be leveraged for group recommendations. In this paper, an automatic user grouping model is introduced that obtains information about users and their preferences through an LBSN. The preferences of the users, proximity of the places the users have visited in terms of spatial range, users’ free days, and the social relationships among users are extracted automatically from location histories and users’ profiles in the LBSN. These factors are combined to determine the similarities among users. The users are partitioned into groups based on these similarities. Group size is the key to coordinating group members and enhancing their satisfaction. Therefore, a modified k-medoids method is developed to cluster users into groups with specific sizes. To evaluate the efficiency of the proposed method, its mean intra-cluster distance and its distribution of cluster sizes are compared to those of general clustering algorithms. The results reveal that the proposed method compares favourably with general clustering approaches, such as k-medoids and spectral clustering, in separating users into groups of a specific size with a lower mean intra-cluster distance.

Balancing the dilution and oddity effects: decisions depend on body size.

Directory of Open Access Journals (Sweden)

Gwendolen M Rodgers

Full Text Available Grouping behaviour, common across the animal kingdom, is known to reduce an individual's risk of predation; particularly through dilution of individual risk and predator confusion (predator inability to single out an individual for attack. Theory predicts greater risk of predation to individuals more conspicuous to predators by difference in appearance from the group (the 'oddity' effect. Thus, animals should choose group mates close in appearance to themselves (eg. similar size, whilst also choosing a large group.We used the Trinidadian guppy (Poecilia reticulata, a well known model species of group-living freshwater fish, in a series of binary choice trials investigating the outcome of conflict between preferences for large and phenotypically matched groups along a predation risk gradient. We found body-size dependent differences in the resultant social decisions. Large fish preferred shoaling with size-matched individuals, while small fish demonstrated no preference. There was a trend towards reduced preferences for the matched shoal under increased predation risk. Small fish were more active than large fish, moving between shoals more frequently. Activity levels increased as predation risk decreased. We found no effect of unmatched shoal size on preferences or activity.Our results suggest that predation risk and individual body size act together to influence shoaling decisions. Oddity was more important for large than small fish, reducing in importance at higher predation risks. Dilution was potentially of limited importance at these shoal sizes. Activity levels may relate to how much sampling of each shoal was needed by the test fish during decision making. Predation pressure may select for better decision makers to survive to larger size, or that older, larger fish have learned to make shoaling decisions more efficiently, and this, combined with their size relative to shoal-mates, and attractiveness as prey items influences shoaling

The effect of body coloration and group size on social partner preferences in female fighting fish (Betta splendens).

Science.gov (United States)

Blakeslee, C; McRobert, S P; Brown, A C; Clotfelter, E D

2009-02-01

Females of the fighting fish Betta splendens have been shown to associate with other B. splendens females in a manner reminiscent of shoaling behavior. Since body coloration varies dramatically in this species, and since body coloration has been shown to affect shoalmate choice in other species of fish, we examined the influence of body coloration on association preferences in female B. splendens. In dichotomous choice tests, B. splendens females spent more time swimming near groups of females (regardless of coloration) than swimming near an empty chamber, and chose to swim near fish of similar coloration to their own when choosing between two distinctly colored groups of females. When examining the interplay between body coloration and group size, focal fish spent more time swimming near larger groups (N=5) of similarly colored fish than swimming near an individual female of similar coloration. However, focal fish showed no preference when presented with an individual female of similar coloration and a larger group of females of dissimilar coloration. These results suggest that association choices in B. splendens females are strongly affected by both body coloration and by group size.

Concentrations and size distributions of fine aerosol particles measured at roof level in urban zone

Science.gov (United States)

Despiau, S.; Croci, D.

2007-05-01

During the experimental Field Experiments to Constrain Models of Atmospheric Pollution and Transport of Emissions (ESCOMPTE) campaign in June-July 2001, concentrations and size distributions of fine particles (14-722 nm) were measured at roof level in downtown Marseille (France). Part of the campaign was dedicated to the study of aerosol behavior in relation to strong photochemical events (which were identified as "IOP" days) and their regional modeling. The analysis of the concentration variations and the evolution of average diurnal size distribution showed that an "IOP day" is not characterized by a specific concentration or its variation, nor by a specific evolution of the average size distribution. The morning traffic rush is detected at roof level by a net increase in particle concentration over the whole size range measured, indicating a production of ultrafine particles by the traffic but also the raising to roof level of particles of the accumulation mode. The increase is observed about 1 hour after the traffic peak at street level, which is characterized by strong increases in NOx and CO concentrations. The corresponding flux of particles at roof level has been estimated around 3 × 104 cm-2 s-1. A specific signature characterized by a strong and rapid burst of concentration (factor 2 to 4 in 15 min) of particles between 25 and 50 nm, independent of the traffic source, has been detected on six occasions during the campaign. These events occur systematically around noon, in cases of strong radiation, low relative humidity, and common wind direction. Despite the high-diameter value of these particles, it is suggested that they could result from a specific "secondary aerosol process" event involving ozone, biogenic, and/or anthropogenic gas precursors like iodine and VOCs.

The Value of Perioperative Levels of ACTH, DHEA, and DHEA-S and Tumor Size in Predicting Recurrence of Cushing Disease.

Science.gov (United States)

El Asmar, Nadine; Rajpal, Aman; Selman, Warren R; Arafah, Baha M

2018-02-01

Despite the development of hypocortisolemia after corticotroph surgical adenomectomy, 15% to 20% patients have recurrence of Cushing disease (CD). In this study, we investigated the effect of tumor size and the value of perioperative assessment of corticotropin (ACTH) and adrenal steroid levels in predicting recurrence. Perioperatively, no glucocorticoids were administered until the serum cortisol was ≤3 μg/dL. Blood samples were obtained before and repeatedly after adenomectomy in 79 patients with CD. Of these, 66 had a nadir serum cortisol of ≤3.0 μg/dL and clinical and biochemical remissions. During a median follow-up of 131 months, 11 of 66 had disease recurrence (REC), whereas 55 of 66 did not (NO-REC). Preoperative hormone levels in the REC and NO-REC groups were similar. After adenomectomy, a brief and similar increase in ACTH, cortisol, and dehydroepiandrosterone (DHEA) levels was observed in both groups followed by gradual decline in those levels. Although REC and NO-REC patients had similar cortisol levels (3.4 ± 1.7 μg/dL vs 2.9 ± 2.2 μg/dL) at the 36th postoperative hour, their respective ACTH (33 ± 7.1 ng/L vs 12.1 ± 5.4 ng/L; P 20 in all REC patients and disease recurrence, particularly in those with profound hypocortisolemia. Copyright © 2017 Endocrine Society

Discrete level schemes sublibrary. Progress report by Budapest group

International Nuclear Information System (INIS)

Oestor, J.; Belgya, T.; Molnar, G.L.

1997-01-01

An entirely new discrete levels file has been created by the Budapest group according to the recommended principles, using the Evaluated Nuclear Structure Data File, ENSDF as a source. The resulting library contains 96,834 levels and 105,423 gamma rays for 2,585 nuclei, with their characteristics such as energy, spin, parity, half-life as well gamma-ray energy and branching percentage

Group Representations and Intergroup Bias: Positive Affect, Similarity, and Group Size.

Science.gov (United States)

Dovidio, John F.; And Others

1995-01-01

Examined how social appearance and affective factors can influence social categorization and intergroup bias. Positive affect increased the extent to which subjects formed inclusive group representations, anticipating that the members of two groups would feel like one. Subjects in dissimilarly dressed groups expected the members to feel less like…

Population size, group composition and behavioural ecology of geladas (Theropithecus gelada) and human-gelada conflict in Wonchit Valley, Ethiopia.

Science.gov (United States)

Kifle, Zewdu; Belay, Gurja; Bekele, Afework

2013-11-01

Primates that live in protected areas are intensively studied; however, those that live outside protected areas are less studied by primatologists. Therefore, the present study was carried out outside protected areas on the endemic gelada (Theropithecus gelada) to estimate the population size and group composition and human-gelada conflict in Wonchit Valley, Ethiopia from August 2008-March 2009. Total count method was used to determine the population size and group composition of geladas. A band of geladas was selected to carry out behavioural research. Data were collected on activity, diet and ranging patterns for one band of geladas using scan samples at 15 min intervals. Data on human-gelada conflict was gathered using questionnaire interview method. The total number of geladas in the study area was 1525. The average size of one-male unit was 16.96. Adult male to adult female sex ratio was 1.00:6.61. The average size of the band was 58.03. Group size ranged from 3 to 220. Geladas spent 65.2% of their time feeding, 16.3% moving, 4.6% resting and 13.9% socializing. The total time spent feeding on grass blades was 83.8% and 11.8% for bulbs and roots. The home range size was 1.5 km2 during the dry season and 0.2 km2 during the wet season. Geladas in the study area caused crop damage and shared pasture and drinking water with livestock. They consume crops during harvesting stage more than the seedling and vegetative stages. The study has immense contribution for the conservation and management of this endemic primate in unprotected areas.

12 CFR 1282.17 - Affordability-Income level definitions-family size and income known (owner-occupied units, actual...

Science.gov (United States)

2010-01-01

... GOALS AND MISSION Housing Goals § 1282.17 Affordability—Income level definitions—family size and income..., for rental housing, family size and income information for the dwelling unit is known to the... sizes: Number of persons in family Percentageof area median income 1 70 2 80 3 90 4 100 5 or more...

Immunoconglutinin levels in normal and diseased population groups in Southern Africa

Science.gov (United States)

Watson, K. C.

1971-01-01

Immunoconglutinin (I-K) levels were measured in adult blood donors of European and African origin and in patients with the following diseases: acute typhoid fever, amoebic liver abscess, chronic liver disease and primary hepatoma. The lowest levels were found in the white donor group and the highest in those with chronic liver disease and those with primary hepatoma. African donors had levels higher than white donors which may relate to chronic infection and particularly chronic parasitic infestation. There was poor correlation between `O' and `H' antibodies and I-K levels in the typhoid group. In those with chronic liver disease there was some correlation between I-K levels and total γ-globulin and also with raised IgM and IgA levels but not with raised IgG. PMID:4103887

Three Levels of Diversity: An Examination of the Complex Relationship Between Diversity, Group Cohesiveness, Sexual Harassment, Group Performance, and Time

National Research Council Canada - National Science Library

Whaley, Gary

1998-01-01

...: surface, working, and deep level diversity. The author explains the nature of the relationship between the three levels of diversity and posits a general model of organizational behavior including diversity, group cohesiveness, group...

Scalable group level probabilistic sparse factor analysis

DEFF Research Database (Denmark)

Hinrich, Jesper Løve; Nielsen, Søren Føns Vind; Riis, Nicolai Andre Brogaard

2017-01-01

Many data-driven approaches exist to extract neural representations of functional magnetic resonance imaging (fMRI) data, but most of them lack a proper probabilistic formulation. We propose a scalable group level probabilistic sparse factor analysis (psFA) allowing spatially sparse maps, component...... pruning using automatic relevance determination (ARD) and subject specific heteroscedastic spatial noise modeling. For task-based and resting state fMRI, we show that the sparsity constraint gives rise to components similar to those obtained by group independent component analysis. The noise modeling...... shows that noise is reduced in areas typically associated with activation by the experimental design. The psFA model identifies sparse components and the probabilistic setting provides a natural way to handle parameter uncertainties. The variational Bayesian framework easily extends to more complex...

Morphing Wing Weight Predictors and Their Application in a Template-Based Morphing Aircraft Sizing Environment II. Part 2; Morphing Aircraft Sizing via Multi-level Optimization

Science.gov (United States)

Skillen, Michael D.; Crossley, William A.

2008-01-01

This report presents an approach for sizing of a morphing aircraft based upon a multi-level design optimization approach. For this effort, a morphing wing is one whose planform can make significant shape changes in flight - increasing wing area by 50% or more from the lowest possible area, changing sweep 30 or more, and/or increasing aspect ratio by as much as 200% from the lowest possible value. The top-level optimization problem seeks to minimize the gross weight of the aircraft by determining a set of "baseline" variables - these are common aircraft sizing variables, along with a set of "morphing limit" variables - these describe the maximum shape change for a particular morphing strategy. The sub-level optimization problems represent each segment in the morphing aircraft's design mission; here, each sub-level optimizer minimizes fuel consumed during each mission segment by changing the wing planform within the bounds set by the baseline and morphing limit variables from the top-level problem.

Group cohesion in sports teams of different professional level

Directory of Open Access Journals (Sweden)

Vazha M. Devishvili

2017-12-01

Full Text Available Background. Team sports are not only the most exciting sporting events. but also complex activities that make serious demands on players. The effectiveness of the team depends not only on the high level of gaming interaction. but also on the relationship between the players. The work is based on the material of sports teams and is devoted to the study of the phenomenon of group cohesion. As a basic model. the authors choose a 4-factor model that describes cohesion in sports teams. The paper also considered the phenomenon of the emergence of the aggregate subject in the process of joint activity. when the participants feel themselves as a whole and experience feelings of satisfaction and a surge of energy. Objective. The main objective of the work is to investigate the relationship between the level of team cohesion and subjective feelings of unity of its players. As additional variables in the study there is a sport (football and volleyball and team level (amateur and professional. To test the assumptions. two methods were used (the Sport Team Cohesion Questionnaire and the Subject Unity Index. which allow not only to determine the overall level of cohesion and unity. but also to reveal the structure of both phenomena. The study involved two men’s volleyball and two men’s football teams of different ages: 8-9 years (39 athletes; 12-14 years (24 athletes and 18-25 years (41 athletes. Design. For amateur groups represented by children’s and teenage sports teams. significant correlations between unity and unity were obtained (r = 0.618. p <0.01; r = 0.477. p <0.05. For professional teams. no significant correlations were found. Influence of the sport on cohesion is also different for amateur and professional teams. In the first case. the cohesion is higher for football players (U = 118. p <0.05. and in the second case for volleyball players (U = 124. p <0.05. Results. The findings indicate that the professional level of players affects group

The Relationships among Group Size, Participation, and Performance of Programming Language Learning Supported with Online Forums

Science.gov (United States)

Shaw, Ruey-Shiang

2013-01-01

This study examined the relationships among group size, participation, and learning performance factors when learning a programming language in a computer-supported collaborative learning (CSCL) context. An online forum was used as the CSCL environment for learning the Microsoft ASP.NET programming language. The collaborative-learning experiment…

The evolution of cooperation in spatial groups

International Nuclear Information System (INIS)

Zhang Jianlei; Zhang Chunyan; Chu Tianguang

2011-01-01

Research highlights: → We propose a model of evolutionary games in which individuals are organized into networked groups. → We show that the social dilemma can be resolved and high cooperation levels are attained. → Larger average group size would lead to lower cooperation level but higher average payoffs. → The results show that higher expectations can bring the system with larger average payoffs. - Abstract: Much of human cooperation remains an evolutionary riddle. There is evidence that individuals are often organized into groups in many social situations. Inspired by this observation, we propose a simple model of evolutionary public goods games in which individuals are organized into networked groups. Here, nodes in the network represent groups; the edges, connecting the nodes, refer to the interactions between the groups. Individuals establish public goods games with partners in the same group and migrate among neighboring groups depending on their payoffs and expectations. We show that the paradigmatic public goods social dilemma can be resolved and high cooperation levels are attained in structured groups, even in relatively harsh conditions for cooperation. Further, by means of numerical simulations and mean-field analysis, we arrive at the result: larger average group size and milder cooperation environment would lead to lower cooperation level but higher average payoffs of the entire population. Altogether, these results emphasize that our understanding of cooperation can be enhanced by investigations of how spatial groups of individuals affect the evolution dynamics, which might help in explaining the emergence and evolution of cooperation.

Correlation Between Echinoidea Size and Threat Level

Science.gov (United States)

Bakshi, S.; Lee, A.; Heim, N.; Payne, J.

2017-12-01

Echinoidea (or sea urchins), are small, spiny, globular, animals that populate the seafloors of nearly the entire planet. Echinoidea have existed on Earth since the Ordovician period, and from their archaic origin there is much to be learned about the relationship between Echinoidea body size and how it affects the survivability of the individual. The goal of this project is to determine how Echinoidea dimensions such as body volume, area, and length compare across extinct and extant species by plotting Echinoidea data in R. We will use stratigraphic data as a source to find which species of sea urchin from our data is extinct. We will then create three sets of three histograms of the size data for each type of measurement. One set will include histograms for sea urchin length, area, and volume. The other set will include histograms for extinct sea urchin length, area, and volume. The last set will include histograms for extant sea urchin length, area, and volume. Our data showed that extant sea urchins had a larger size, and extinct sea urchins were smaller. Our length data showed that the average length of all sea urchins were 54.95791 mm, the average length of extinct sea urchins were 51.0337 mm, and the average length of extant sea urchins were 66.12774 mm. There is a generally increasing trend of size over time, except for a small outlier about 350 million years ago, where echinoderm extinction selected towards larger species and biovolume was abnormally high. Our data also showed that over the past 200 million years, echinoderm extinction selectivity drove slightly smaller sea urchins towards extinction, further supporting the idea that a larger size was and still is advantageous for echinoderms.

Clinical significance of changes of serum osteocalcin (BGP) levels in subjects of different age-groups

International Nuclear Information System (INIS)

Jiang Lihua; Zhang Jin; Han Cuihua; Ouyang Qiaohong

2006-01-01

Objective: To investigate the changes of serum BGP levels in different age-groups. Methods: Serum BGP levels were determined with RIA in 306 subjects of different age-groups. Results: The serum BGP levels were highest in subjects of the pre-adolescent group (age5-15, n=60, vs other groups, all P 50, n=80, P<0.001). Levels in the middle age group were the lowest and were significantly lower than those in the old age group (P<0.001). No sex related differences were observed in the pre-adolescent and middle age groups, but in the youth group, serum BGP levels were significantly higher in the males than those in the females (P<0.05). However, in the old age group, the reverse was true i.e. values being significantly higher in the females (vs males, P<0.01). Conclusion: Serum BGP levels varied greatly among the different age groups. (authors)

Reciprocal Relations between Student-Teacher Relationship and Children's Behavioral Problems: Moderation by Child-Care Group Size

Science.gov (United States)

Skalická, Vera; Belsky, Jay; Stenseng, Frode; Wichstrøm, Lars

2015-01-01

In this Norwegian study, bidirectional relations between children's behavior problems and child-teacher conflict and closeness were examined, and the possibility of moderation of these associations by child-care group size was tested. Eight hundred and nineteen 4-year-old children were followed up in first grade. Results revealed reciprocal…

Grain-size based sea-level reconstruction in the south Bohai Sea during the past 135 kyr

Science.gov (United States)

Yi, Liang; Chen, Yanping

2013-04-01

Future anthropogenic sea-level rise and its impact on coastal regions is an important issue facing human civilizations. Due to the short nature of the instrumental record of sea-level change, development of proxies for sea-level change prior to the advent of instrumental records is essential to reconstruct long-term background sea-level changes on local, regional and global scales. Two of the most widely used approaches for past sea-level changes are: (1) exploitation of dated geomorphologic features such as coastal sands (e.g. Mauz and Hassler, 2000), salt marsh (e.g. Madsen et al., 2007), terraces (e.g. Chappell et al., 1996), and other coastal sediments (e.g. Zong et al., 2003); and (2) sea-level transfer functions based on faunal assemblages such as testate amoebae (e.g. Charman et al., 2002), foraminifera (e.g. Chappell and Shackleton, 1986; Horton, 1997), and diatoms (e.g. Horton et al., 2006). While a variety of methods has been developed to reconstruct palaeo-changes in sea level, many regions, including the Bohai Sea, China, still lack detailed relative sea-level curves extending back to the Pleistocene (Yi et al., 2012). For example, coral terraces are absent in the Bohai Sea, and the poor preservation of faunal assemblages makes development of a transfer function for a relative sea-level reconstruction unfeasible. In contrast, frequent alternations between transgression and regression has presumably imprinted sea-level change on the grain size distribution of Bohai Sea sediments, which varies from medium silt to coarse sand during the late Quaternary (IOCAS, 1985). Advantages of grainsize-based relative sea-level transfer function approaches are that they require smaller sample sizes, allowing for replication, faster measurement and higher spatial or temporal resolution at a fraction of the cost of detail micro-palaeontological analysis (Yi et al., 2012). Here, we employ numerical methods to partition sediment grain size using a combined database of

Normal ventricular size and changes with age in pediatric groups on computed tomography

International Nuclear Information System (INIS)

Nakada, Yoshitaka; Nose, Tadao; Enomoto, Takao; Maki, Yutaka

1980-01-01

The purpose of this report is to determine the normal value of the ventricular size on CT, snd analyze its changes with age in normal pediatric group. Materials and Methods: We searched through our 240 normal pediatric CT film files, aged 4 months to 14 years. Scans were performed on Hitachi CT-II scanner, using 10 mm collimation. Results: 1. The width of the third ventricle showed the same value in all pediatric groups, the mean value of its being 4.8 mm (SD 1.3 mm). 2. Bicaudate cerebroventricular indexes of the anterior horns of lateral ventricles (interecarlate distance/transverse diameter of the brain x100) were 15.3 in infants under one year, 13.8 in the age of one year and 12.7 in the children over two years. The indexes were almost the same in old age group over the age of three years. 3. The upper limit of the normal inverse cella media index (minium width of cella media/transverse diameter of the brain x100) was 31. Therefore the cases with the index above this range can be diagnosed as hydrocephalic. 4. The shape of the anterior horns of lateral ventricles was Y-shaped in infants under one year. II-shaped (paralied shaped) in the age of 1 - 12 years, and again it was Y-shaped in the group over 12 years. 5. In the age group under one year, the temporal horns of the lateral ventricles were visualized in about 60% cases, while the figure decreased to 20% in the older group. (author)

Examination of group cohesiveness levels and goal orientations of basketball players

Directory of Open Access Journals (Sweden)

Ötkan Can Çavin

2017-01-01

Full Text Available This research intends to examine goal orientation and group cohesiveness levels of basketball players. 243 mature players who play in the leagues of Turkish Basketball Federation in 2016- 2017 season participated the study. “Task and Ego Orientation in Sports” and “Group Cohesiveness” questionnaires are used in study. While frequency, arithmetic mean and standard deviation is used for the analysis of data, T-Test, One-Way Analysis of Variance (ANOVA and Post-Hoc test statistics (Tukey HSD are used for independent samples. Depending on the variables of gender and educational background of players, a significant difference is identified in sub-dimension of Task Attraction of Group and a low-level negatively significant difference is identified between Ego Orientation in terms of age and sportive age. Significant differences are identified between the Perception of Team Success and sub-dimensions of Social Integration of Group and Social Attraction of Group. No statistically significant difference can be found for the variable of time spent in team in terms of group cohesiveness and goal orientation.

Core level shifts in group IV semiconductors and semimetals

International Nuclear Information System (INIS)

Yin, S.; Tosatti, E.

1981-08-01

We calculate the core level binding energy shift from the isolated atom to the crystalline solid, for group IV elemental semiconductors. This is done by simple extension of Johansson and Martensson's scheme for metals. We show that the core level energy in a nonmetal must be measured by the photo absorption (''core exciton'') threshold rather than by photo emission. As a byproduct, a simple scheme is also devised to evaluate impurity heats of solutions in semiconductors. (author)

The Significance of Farm Size in the Evaluation of Labour Productivity in Agriculture

Directory of Open Access Journals (Sweden)

Martina Novotná

2016-01-01

Full Text Available The paper deal with the analysis of difference in labour productivity of farms categorised according to their size, to determine if the set subsidy system influences labour productivity in the size groups of the farms. The source of data for enterprises analysis was the firms database, which contains accounting data of 926 farms with at least one employee. The observed data were from the 6 year period (2007–2012. The farms were divided, according to their size into four categories defined by the European Commission: micro, small, medium and large enterprises. The analysis of the labour productivity I based on the added value and labour costs revealed that there are big differences of the labour productivity levels in particular size groups of farms. The further analysis revealed that an adjustment of the farm approach of the labour productivity, when the paid operation subsidies are added (labour productivity II, changes this conclusion and the differences between particular size groups of farms decreased. Using σ-convergence, it was proved that the relative variability of the labour productivity II values decreased significantly in the case of the medium-sized farms. We can say that subsidies significantly influence the labour productivity in farms. On one hand, there is decrease of differences between the level values of particular size groups of farms; on the other hand, there is no significant decrease its variability (except the medium-sized farms.

Population is the main driver of war group size and conflict casualties.

Science.gov (United States)

Oka, Rahul C; Kissel, Marc; Golitko, Mark; Sheridan, Susan Guise; Kim, Nam C; Fuentes, Agustín

2017-12-26

The proportions of individuals involved in intergroup coalitional conflict, measured by war group size (W), conflict casualties (C), and overall group conflict deaths (G), have declined with respect to growing populations, implying that states are less violent than small-scale societies. We argue that these trends are better explained by scaling laws shared by both past and contemporary societies regardless of social organization, where group population (P) directly determines W and indirectly determines C and G. W is shown to be a power law function of P with scaling exponent X [demographic conflict investment (DCI)]. C is shown to be a power law function of W with scaling exponent Y [conflict lethality (CL)]. G is shown to be a power law function of P with scaling exponent Z [group conflict mortality (GCM)]. Results show that, while W/P and G/P decrease as expected with increasing P, C/W increases with growing W. Small-scale societies show higher but more variance in DCI and CL than contemporary states. We find no significant differences in DCI or CL between small-scale societies and contemporary states undergoing drafts or conflict, after accounting for variance and scale. We calculate relative measures of DCI and CL applicable to all societies that can be tracked over time for one or multiple actors. In light of the recent global emergence of populist, nationalist, and sectarian violence, our comparison-focused approach to DCI and CL will enable better models and analysis of the landscapes of violence in the 21st century. Copyright © 2017 the Author(s). Published by PNAS.

Estimation of Tooth Size Discrepancies among Different Malocclusion Groups

OpenAIRE

Hasija, Narender; Bala, Madhu; Goyal, Virender

2014-01-01

ABSTRACT Regards and Tribute: Late Dr Narender Hasija was a mentor and visionary in the light of knowledge and experience. We pay our regards with deepest gratitude to the departed soul to rest in peace. Bolton’s ratios help in estimating overbite, overjet relationships, the effects of contemplated extractions on posterior occlusion, incisor relationships and identification of occlusal misfit produced by tooth size discrepancies. Aim: To determine any difference in tooth size discrepancy in a...

Effect of heliostat size on the levelized cost of electricity for power towers

Science.gov (United States)

Pidaparthi, Arvind; Hoffmann, Jaap

2017-06-01

The objective of this study is to investigate the effects of heliostat size on the levelized cost of electricity (LCOE) for power tower plants. These effects are analyzed in a power tower with a net capacity of 100 MWe, 8 hours of thermal energy storage and a solar multiple of 1.8 in Upington, South Africa. A large, medium and a small size heliostat with a total area of 115.56 m2, 43.3 m2 and 15.67 m2 respectively are considered for comparison. A radial-staggered pattern and an external cylindrical receiver are considered for the heliostat field layouts. The optical performance of the optimized heliostat field layouts has been evaluated by the Hermite (analytical) method using SolarPILOT, a tool used for the generation and optimization of the heliostat field layout. The heliostat cost per unit is calculated separately for the three different heliostat sizes and the effects due to size scaling, learning curve benefits and the price index is included. The annual operation and maintenance (O&M) costs are estimated separately for the three heliostat fields, where the number of personnel required in the field is determined by the number of heliostats in the field. The LCOE values are used as a figure of merit to compare the different heliostat sizes. The results, which include the economic and the optical performance along with the annual O&M costs, indicate that lowest LCOE values are achieved by the medium size heliostat with an area of 43.3 m2 for this configuration. This study will help power tower developers determine the optimal heliostat size for power tower plants currently in the development stage.

Comparison of energy balance between two different-sized groups of Japanese macaques (Macaca fuscata yakui).

Science.gov (United States)

Kurihara, Yosuke; Hanya, Goro

2017-07-01

Quantifying the energy balance is essential for testing socio-ecological models. To reveal costs and benefits of group living in Japanese macaques from the perspective of feeding competition, Kurihara and Hanya (Am J Primatol 77:986-1000, 2015) previously compared feeding behavior between two different-sized groups of macaques (larger group 30-35 individuals; smaller group 13-15 individuals) in the coastal forest of Yakushima, Japan. The results suggested that the larger group exhibited greater feeding effort because of intragroup scramble competition and that the smaller group suffered from higher travel costs, possibly owing to intergroup contest competition. However, it remained unclear whether the behavioral differences affected their energy budgets. The present study examined energetic consequences of the different feeding behaviors in the two groups. Using behavioral data from 10 to 13 adult females and nutritional composition of food items, we compared ingestion rates, energetic/nutritional content of diet, and energy budgets between the two groups. Ingestion rates and energetic/nutritional content of diet did not differ between the two groups. Despite the higher feeding effort of the larger group, energy intake did not differ between the two groups. Energy expenditure did not differ between the two groups because higher travel costs were negated by lower feeding effort in the smaller group. Consequently, the energy balance did not differ between the two groups. We demonstrated that the behavioral measures of feeding competition were not translated into their energetic condition; moreover, our findings re-emphasize the importance of quantifying behavioral and fitness measures for interpreting variation in feeding behavior properly.

A multilevel perspective on faultlines: Differentiating the effects between group- and organizational-level faultlines.

Science.gov (United States)

Bezrukova, Katerina; Spell, Chester S; Caldwell, David; Burger, Jerry M

2016-01-01

Integrating the literature on faultlines, conflict, and pay, we drew on the basic principles of multilevel theory and differentiated between group- and organizational-level faultlines to introduce a novel multilevel perspective on faultlines. Using multisource, multilevel data on 30 Major League Baseball (MLB) teams, we found that group-level faultlines were negatively associated with group performance, and that internally focused conflict exacerbated but externally focused conflict mitigated this effect. Organizational-level faultlines were negatively related to organizational performance, and were most harmful in organizations with high levels of compensation. Implications for groups and teams in the sports/entertainment and other industries are discussed. (c) 2016 APA, all rights reserved).

A meta-analysis of development aid allocation:  The effects of income level and population size

DEFF Research Database (Denmark)

Paldam, Martin

The effect on aid allocation of the income level and population size in the recipient country is  analyzed. The data show that both variables have a significant and robust negative effect, but  they explain only a small part of the variation. The main thrust of the paper is a meta-analysis of the......The effect on aid allocation of the income level and population size in the recipient country is  analyzed. The data show that both variables have a significant and robust negative effect, but  they explain only a small part of the variation. The main thrust of the paper is a meta...

Airport level of service: A model according to departing passengers’ perceptions at a small-sized airport

Directory of Open Access Journals (Sweden)

Max Well Elias Gonçalves

2017-04-01

Full Text Available Purpose: This study proposes a conceptual model of level of service evaluation to a small-sized airport with a focus on departing passengers. Design/Methodology: The variables selected to compose the model were chosen according to their adequacy to departing passengers and the airport’s characteristics. A survey was conducted, and, posteriorly, exploratory factor analysis was used in order to verify the adequacy of the conceptual model proposed and also to improve it according to the results obtained. Findings: The results show that the level of service of the airport is composed of three dimensions: airport characteristics, passenger processing, and prices. The relative importance of the dimensions according to their contribution to the composition of the airport’s overall level of service was also determined. Originality/value: The paper combines theoretical and practical findings in a model for level of service evaluation to a small-sized airport from an air transportation management perspective.

Impact of the size of the class on pupils’ psychosocial well-being

DEFF Research Database (Denmark)

Nielsen, Bo Birk

Most research on class size effect focuses on pupils’ school achievement but few on pupils’ psychosocial well-being. On the other hand an increasing number of studies have showed that there is a link between pupils’ psychosocial well-being and their school achievement. 97 Danish typically...... developing 3rd grade pupils were tested. They were divided into 3 class size groups: Small (10 pupils), Medium (20 pupils), and Large (25 pupils). The average age (10 years) and the proportion of boys and girls (50%) and SES (medium) were similar in the 3 class size groups. Pupils’ psychosocial well-being...... and there was a significant link between lack of understanding of mixed emotions and lower level of self-concept and higher level of anger. These results of this research may contribute to a better understanding of the impact of the class size on pupils’ school achievement via the identification of risk factors...

REPERCUSSIONS OF THE INCREASE IN GROUP SIZE IN EARLY CHILDHOOD EDUCATION: THE PERSPECTIVE OF EDUCATORS

Directory of Open Access Journals (Sweden)

Casla, Marta

2014-10-01

Full Text Available This work describes some of the consequences of new regulations on nurseries in the Madrid area that are related to ratios and group size (especially after the decree 18/2008. Analyses are based on educators and education staff’s point of view. Special emphasis is made on consequences on children behavior. Two hundred and seventy seven professionals that belonged to more than 53 nurseries of Madrid area voluntarily answered a survey with open questions about educative process and child’s behavior. Qualitative and quantitative analyses show that, from educator’s point of view, increasing ratio child-educator has consequences in the variables explored. Main effects were found for the activities made in classrooms (loosing educative standards, hygiene and supply routines (loosing intrinsic values and autonomy support, space and time distribution, support staff organization and relation with families (reduced to quick information interchanges. Directors, classroom tutors and support educators perceive these changes in a similar fashion. The vast majority perceived changes on children’s behavior- increases in the number of conflicts and anxiety. These results agree with previous research on the influence of child-educators ratios and group size on quality of education. Implications for child development are discussed. This paper is published in Spanish.

Cheating monkeys undermine group strength in enemy territory.

Science.gov (United States)

Crofoot, Margaret Chatham; Gilby, Ian C

2012-01-10

In many social animals, group-mates cooperate to defend their range against intrusion by neighboring groups. Because group size tends to be highly variable, such conflicts are often asymmetric. Although numerical superiority is assumed to provide a competitive advantage, small groups can generally defend their ranges, even when greatly outnumbered. The prevailing explanation for this puzzling phenomenon is that individuals in relatively large groups experience a greater temptation to flee from conflicts, in effect leveling the balance of power. Using playback experiments simulating territorial intrusions by wild capuchin monkey (Cebus capucinus) groups, we show that such a collective action problem does indeed undermine the competitive ability of large groups. Focal capuchins were more likely to run away from territorial intrusions when their group had a numeric advantage; each one-individual increase in relative group size raised the odds of flight by 25%. However, interaction location had a more important impact on individuals' reactions, creating a strong home-field advantage. After controlling for relative group size, the odds that a focal animal fled were 91% lower in experiments that occurred in the center compared with on the edge of its group's range, whereas the odds that it rushed toward the speaker were more than sixfold higher. These location-dependent patterns of defection and cooperation create a competitive advantage for residents over intruders across a wide range of relative group sizes, which may stabilize range boundaries and provide a general explanation for how groups of widely divergent sizes can coexist, even in the face of intense intergroup competition.

REDUCTION OF CLASSROOM NOISE LEVELS USING GROUP CONTINGENCIES

OpenAIRE

Ring, Brandon M.; Sigurdsson, Sigurdur O.; Eubanks, Sean L.; Silverman, Kenneth

2014-01-01

The therapeutic workplace is an employment-based abstinence reinforcement intervention for unemployed drug users where trainees receive on-the-job employment skills training in a classroom setting. The study is an extension of prior therapeutic workplace research, which suggested that trainees frequently violated noise standards. Participants received real-time graphed feedback of noise levels and had the opportunity to earn monetary group reinforcement for maintaining a low number of noise v...

Factors associated with tumor size of hepatocellular carcinoma

Science.gov (United States)

Siregar, G. A.; Buulolo, B. A.

2018-03-01

Determining the association of age and laboratory parameters with tumor size of hepatocellular carcinoma (HCC). The study was at Adam Malik Hospital Medan from June- December 2016. 100 HCC patients were enrolled; those with excluding liver metastatic. Baseline characteristics of gender, age, obtaining etiology of HCC. Liver function tests, viral marker, and INR were done. Based on tumor size from abdomen CT, patients were three groups: tumor size below 3 cm, 3-5 cm, and above 5 cm size. Patients were also divided based on Child-Pugh class. Correlation of age and laboratory results with tumor size of HCC patients were analyzed. Age have negative correlation with tumor size in HCC patients (r=-0.297, p=0.032) while AFP have positive correlation with tumor size (r0.446, p=<0.001). Total bilirubin, AST, and ALT have negative correlation but non-significant (r=-0.045, -0.078, - 0.126 respectively). Albumin and INR have positive correlation but non-significant (r=0.021, 0.112 respectively). Our study suggests that older age correlates with smaller tumor size, while AFP level has a significant correlation with tumor size in HCC patients. AFP level may be a useful marker for determining the prognosis of HCC patients.

Group as social microcosm: Within-group interpersonal style is congruent with outside group relational tendencies.

Science.gov (United States)

Goldberg, Simon B; Hoyt, William T

2015-06-01

The notion that individuals' interpersonal behaviors in the context of therapy reflects their interpersonal behaviors outside of therapy is a fundamental hypothesis underlying numerous systems of psychotherapy. The social microcosm hypothesis, in particular, claims the interpersonal therapy group becomes a reflection of group members' general tendencies, and can thus be used as information about members' interpersonal functioning as well as an opportunity for learning and behavior change. The current study tested this hypothesis using data drawn from 207 individuals participating in 22 interpersonal process groups. Ratings were made on 2 key interpersonal domains (Dominance and Affiliation) at baseline and at Weeks 2, 5, and 8 of the group. Two-level multilevel models (with participants nested within groups) were used to account for the hierarchical structure, and the social relations model (SRM; Kenny, 1994) was used to estimate peer ratings (target effects in SRM) unconfounded with rater bias. Participants showed consensus at all time points during the interpersonal process groups on one another's levels of dominance and affiliation. In addition, self- and peer ratings were stable across time and correlated with one another. Importantly, self-ratings made prior to group significantly predicted ratings (self- and peer) made within the group, with effect sizes within the medium range. Taken together, these results provide robust support for the social microcosm hypothesis and the conjecture that interpersonal style within-group therapy is reflective of broader interpersonal tendencies. (c) 2015 APA, all rights reserved).

Prognostic significance of normal-sized ovary in advanced serous epithelial ovarian cancer.

Science.gov (United States)

Paik, E Sun; Kim, Ji Hye; Kim, Tae Joong; Lee, Jeong Won; Kim, Byoung Gie; Bae, Duk Soo; Choi, Chel Hun

2018-01-01

We compared survival outcomes of advanced serous type epithelial ovarian cancer (EOC) patients with normal-sized ovaries and enlarged-ovarian tumors by propensity score matching analysis. The medical records of EOC patients treated at Samsung Medical Center between 2002 and 2015 were reviewed retrospectively. We investigated EOC patients with high grade serous type histology and International Federation of Gynecology and Obstetrics (FIGO) stage IIIB, IIIC, or IV who underwent primary debulking surgery (PDS) and adjuvant chemotherapy to identify patients with normal-sized ovaries. Propensity score matching was performed to compare patients with normal-sized ovaries to patients with enlarged-ovarian tumors (ratio, 1:3) according to age, FIGO stage, initial cancer antigen (CA)-125 level, and residual disease status after PDS. Of the 419 EOC patients, 48 patients had normal-sized ovary. Patients with enlarged-ovarian tumor were younger (54.0±10.3 vs. 58.4±9.2 years, p=0.005) than those with normal-sized ovary, and there was a statistically significant difference in residual disease status between the 2 groups. In total cohort with a median follow-up period of 43 months (range, 3-164 months), inferior overall survival (OS) was shown in the normal-sized ovary group (median OS, 71.2 vs. 41.4 months; p=0.003). After propensity score matching, the group with normal-sized ovary showed inferior OS compared to the group with enlarged-ovarian tumor (median OS, 72.1 vs. 41.4 months; p=0.031). In multivariate analysis for OS, normal-sized ovary remained a significant factor. Normal-sized ovary was associated with poor OS compared with the common presentation of enlarged ovaries in EOC, independent of CA-125 level or residual disease. Copyright © 2018. Asian Society of Gynecologic Oncology, Korean Society of Gynecologic Oncology

Effect of corn silage particle size and level of soybean oil on ruminal ...

African Journals Online (AJOL)

To determine the effects of two corn silage particle size (coarse particle with geometric mean of 5.83 ± 2.47 mm and fine particle with geometric mean of 4.74 ± 2.74 mm) and two levels of soybean oil (0 and 4% of DM) on ruminal mat composition, distribution and consistency, four two years fistulated ruminant Zel ewes (BW ...

Infectious Disease and Grouping Patterns in Mule Deer.

Directory of Open Access Journals (Sweden)

María Fernanda Mejía Salazar

Full Text Available Infectious disease dynamics are determined, to a great extent, by the social structure of the host. We evaluated sociality, or the tendency to form groups, in Rocky Mountain mule deer (Odocoileus hemionus hemionus from a chronic wasting disease (CWD endemic area in Saskatchewan, Canada, to better understand factors that may affect disease transmission. Using group size data collected on 365 radio-collared mule deer (2008-2013, we built a generalized linear mixed model (GLMM to evaluate whether factors such as CWD status, season, habitat and time of day, predicted group occurrence. Then, we built another GLMM to determine factors associated with group size. Finally, we used 3 measures of group size (typical, mean and median group sizes to quantify levels of sociality. We found that mule deer showing clinical signs of CWD were less likely to be reported in groups than clinically healthy deer after accounting for time of day, habitat, and month of observation. Mule deer groups were much more likely to occur in February and March than in July. Mixed-sex groups in early gestation were larger than any other group type in any season. Groups were largest and most likely to occur at dawn and dusk, and in open habitats, such as cropland. We discuss the implication of these results with respect to sociobiology and CWD transmission dynamics.

Effect of canister size on costs of disposal of SRP high-level wastes

International Nuclear Information System (INIS)

McDonell, W.R.

1982-01-01

The current plan for managing the high-level nuclear wastes at the Savannah River Plant (SRP) calls for processing them into solid forms contained in stainless steel canisters for eventual disposal in a federal geologic repository. A new SRP facility called the Defense Waste Processing Facility (DWPF) is being designed for the onsite waste processing operations. Preliminary evaluations indicate that costs of the overall disposal operation will depend significantly on the size of the canisters, which determines the number of waste forms to be processed. The objective of this study was to evaluate the effects of canister size on costs of DWPF process operations, including canister procurement, waste solidification, and interim storage, on offsite transport, and on repository costs of disposal, including provision of suitable waste packages

Brain Size, IQ, and Racial-Group Differences: Evidence from Musculoskeletal Traits.

Science.gov (United States)

Rushton, J. Philippe; Rushton, Elizabeth W.

2003-01-01

Correlated brain size differences with 37 musculoskeletal variables shown in evolutionary textbooks to change with brain size. Findings from a sample of more than 6,000 U.S. military personnel indicate that racial differences in brain size are securely established and are the most likely biological mediators of race differences in intelligence.…

Saturation in Phosphene Size with Increasing Current Levels Delivered to Human Visual Cortex.

Science.gov (United States)

Bosking, William H; Sun, Ping; Ozker, Muge; Pei, Xiaomei; Foster, Brett L; Beauchamp, Michael S; Yoshor, Daniel

2017-07-26

electrical stimulation: phosphene size saturates at a relatively low current level. This finding implies that, with current methods, visual prosthetics will have a limited dynamic range available to control the production of spatial forms and that more advanced stimulation methods may be required. Copyright © 2017 the authors 0270-6474/17/377188-10$15.00/0.

Outcomes of Mixed-Age Groupings. Research Highlights.

Science.gov (United States)

Stegelin, Dolores A.

1997-01-01

A review of the literature on mixed-age settings reveals benefits in the areas of social and cognitive development. Research on the psychosocial advantages of mixed-age groupings is less consistent. Factors such as group size, age range, time together, and context-specific curriculum activities may have a relationship to the level of success and…

Investigating the Group-Level Impact of Advanced Dual-Echo fMRI Combinations

Directory of Open Access Journals (Sweden)

Adam Kettinger

2016-12-01

Full Text Available Multi-echo fMRI data acquisition has been widely investigated and suggested to optimize sensitivity for detecting the BOLD signal. Several methods have also been proposed for the combination of data with different echo times. The aim of the present study was to investigate how these advance echo combination methods provide advantages over the simple averaging of echoes when state-of-the-art group-level random-effect analyses are performed. Both resting-state and task-based dual-echo fMRI data were collected from 27 healthy adult individuals (14 male, mean age = 25.75 years using standard echo-planar acquisition methods at 3T. Both resting-state and task-based data were subjected to a standard image pre-processing pipeline. Subsequently the two echoes were combined as a weighted average, using four different strategies for calculating the weights: (1 simple arithmetic averaging, (2 BOLD sensitivity weighting, (3 temporal-signal-to-noise ratio weighting and (4 temporal BOLD sensitivity weighting. Our results clearly show that the simple averaging of data with the different echoes is sufficient. Advanced echo combination methods may provide advantages on a single-subject level but when considering random-effects group level statistics they provide no benefit regarding sensitivity (i.e. group-level t-values compared to the simple echo-averaging approach. One possible reason for the lack of clear advantages may be that apart from increasing the average BOLD sensitivity at the single-subject level, the advanced weighted averaging methods also inflate the inter-subject variance. As the echo combination methods provide very similar results, the recommendation is to choose between them depending on the availability of time for collecting additional resting-state data or whether subject-level or group-level analyses are planned.

Threat-level-dependent manipulation of signaled body size: dog growls' indexical cues depend on the different levels of potential danger.

Science.gov (United States)

Bálint, Anna; Faragó, Tamás; Miklósi, Ádám; Pongrácz, Péter

2016-11-01

Body size is an important feature that affects fighting ability; however, size-related parameters of agonistic vocalizations are difficult to manipulate because of anatomical constraints within the vocal production system. Rare examples of acoustic size modulation are due to specific features that enable the sender to steadily communicate exaggerated body size. However, one could argue that it would be more adaptive if senders could adjust their signaling behavior to the fighting potential of their actual opponent. So far there has been no experimental evidence for this possibility. We tested this hypothesis by exposing family dogs (Canis familiaris) to humans with potentially different fighting ability. In a within-subject experiment, 64 dogs of various breeds consecutively faced two threateningly approaching humans, either two men or two women of different stature, or a man and a woman of similar or different stature. We found that the dogs' vocal responses were affected by the gender of the threatening stranger and the dog owner's gender. Dogs with a female owner, or those dogs which came from a household where both genders were present, reacted with growls of lower values of the Pitch-Formant component (including deeper fundamental frequency and lower formant dispersion) to threatening men. Our results are the first to show that non-human animals react with dynamic alteration of acoustic parameters related to their individual indexical features (body size), depending on the level of threat in an agonistic encounter.

Group size effects on survivorship and adult development in the gregarious larvae of Euselasia chrysippe (Lepidoptera, Riodinidae)

Science.gov (United States)

P. E. Allen

2010-01-01

Caterpillars living in aggregations may derive several benefits that outweigh the costs, including better survivorship and improved growth rates. I tested whether larval group size had an effect on these two vital rates in Euselasia chrysippe. These caterpillars feed gregariously during all instars and move in processionary form over the host plant...

Place matters: A longitudinal analysis measuring the association between neighbourhood walkability and walking by age group and population center size in Canada.

Science.gov (United States)

Wasfi, Rania; Steinmetz-Wood, Madeleine; Kestens, Yan

2017-01-01

This study examined the influence of walkability on walking behaviour and assessed whether associations varied according to life-stage and population center (PC) size. Walkability scores were obtained for the six-digit postal codes of residential neighbourhoods of 11,200 Canadians, who participated in biennial assessments of the National Population Health Survey from 1994 to 2010. Participants were stratified by age-group. Mixed-effects logistic regression models were used to estimate the influence of cumulative exposure to neighborhood walkability on utilitarian and exercise walking by PC size and life-stage. Associations of neighbourhood walkability with utilitarian and exercise walking varied according to age-group and PC size. Exposure to high walkable neighborhoods was associated with utilitarian walking in younger and older adults in all PC sizes, except for older adults living in a medium PC. Living in a highly walkable neighborhood in a large PC was associated with walking for exercise in younger (OR: 1.42; 95%CI: 1.20-1.67) and older adults (OR: 2.09; 95%CI: 1.51-2.89). Living in highly walkable neighbourhood in a medium PC was associated with walking for exercise in older adults (OR: 1.62; 95%CI: 1.15-2.29). These results emphasize the need to consider the size and nature of every community, and the age-group of a population when implementing strategies to promote walking.

Comparison of bi-level optimization frameworks for sizing and control of a hybrid electric vehicle

NARCIS (Netherlands)

Silvas, E.; Bergshoeff, N.D.; Hofman, T.; Steinbuch, M.

2015-01-01

This paper discusses the integrated design problem related to determining the power specifications of the main subsystems (sizing) and the supervisory control (energy management). Different bi-level optimization methods, with the outer loop using algorithms as Genetic Algorithms, Sequential

Group-Level Organizational Citizenship Behavior in the Education System: A Scale Reconstruction and Validation

Science.gov (United States)

Vigoda-Gadot, Eran; Beeri, Itai; Birman-Shemesh, Taly; Somech, Anit

2007-01-01

Purpose: Most writings on Organizational Citizenship Behavior (OCB) to date have focused on analysis at the individual level and paid less attention to other analytical frameworks at the group level (i.e., team, unit, or organization). This article approaches OCB from the less conventional perspective of group-level activities and uses it to…

Body Size, Extinction Risk and Knowledge Bias in New World Snakes

Science.gov (United States)

Vilela, Bruno; Villalobos, Fabricio; Rodríguez, Miguel Ángel; Terribile, Levi Carina

2014-01-01

Extinction risk and body size have been found to be related in various vertebrate groups, with larger species being more at risk than smaller ones. We checked whether this was also the case for snakes by investigating extinction risk–body size relationships in the New World's Colubroidea species. We used the IUCN Red List risk categories to assign each species to one of two broad levels of threat (Threatened and Non-Threatened) or to identify it as either Data Deficient or Not-Evaluated by the IUCN. We also included the year of description of each species in our analysis as this could affect the level of threat assigned to it (earlier described species had more time to gather information about them, which might have facilitated their evaluation). Also, species detectability could be a function of body size, with larger species tending to be described earlier, which could have an impact in extinction risk–body size relationships. We found a negative relationship between body size and description year, with large-bodied species being described earlier. Description year also varied among risk categories, with Non-Threatened species being described earlier than Threatened species and both species groups earlier than Data Deficient species. On average, Data Deficient species also presented smaller body sizes, while no size differences were detected between Threatened and Non-Threatened species. So it seems that smaller body sizes are related with species detectability, thus potentially affecting both when a species is described (smaller species tend to be described more recently) as well as the amount of information gathered about it (Data Deficient species tend to be smaller). Our data also indicated that if Data Deficient species were to be categorized as Threatened in the future, snake body size and extinction risk would be negatively related, contrasting with the opposite pattern commonly observed in other vertebrate groups. PMID:25409293

Group size effects in two repeated game models of a global climate agreement

International Nuclear Information System (INIS)

Helland, Leif

2002-01-01

What levels of total abatement can one hope for in a global climate agreement. Some potential answers to this question are provided by game theory. This working paper contains a critical discussion of two (prominent) game ,models that answer the question quite pessimistically. Both models take the n-person, infinitely repeated prisoner's dilemma game as their point of departure. The first model is a full information model and utilises the motion of a weakly re negotiation proof equilibrium. This results in the (maybe counterintuitive) prediction that an agreement that can provide high utility to the group will attract less total abatement than an agreement that can only provide low utility to the group. The second model assumes imperfect public information and utilises the notion of a trigger level equilibrium. This results in the (more intuitive) prediction that the level of total abatements will increase with improved verification techniques for a given player set. Still the level of total abatements decrease with an increasing player set for a given verification technique. Empirical implications of the two models are identified and it is argued that one should confront these with experimentally generated data in order to discriminate between the models. One reason for this is that historical data on abatement efforts in a global climate agreement do not exist since no such agreement has entered into force yet. (Author)

Group size effects in two repeated game models of a global climate agreement

Energy Technology Data Exchange (ETDEWEB)

Helland, Leif

2002-07-01

What levels of total abatement can one hope for in a global climate agreement. Some potential answers to this question are provided by game theory. This working paper contains a critical discussion of two (prominent) game ,models that answer the question quite pessimistically. Both models take the n-person, infinitely repeated prisoner's dilemma game as their point of departure. The first model is a full information model and utilises the motion of a weakly re negotiation proof equilibrium. This results in the (maybe counterintuitive) prediction that an agreement that can provide high utility to the group will attract less total abatement than an agreement that can only provide low utility to the group. The second model assumes imperfect public information and utilises the notion of a trigger level equilibrium. This results in the (more intuitive) prediction that the level of total abatements will increase with improved verification techniques for a given player set. Still the level of total abatements decrease with an increasing player set for a given verification technique. Empirical implications of the two models are identified and it is argued that one should confront these with experimentally generated data in order to discriminate between the models. One reason for this is that historical data on abatement efforts in a global climate agreement do not exist since no such agreement has entered into force yet. (Author)

Diabetes Support Groups Improve Patient’s Compliance and Control Blood Glucose Levels

Directory of Open Access Journals (Sweden)

Zamrotul Izzah

2013-09-01

Full Text Available Providing information is not enough to improve diabetic patient’s compliance and achieve goals of therapy. Patient’s good awareness as well as emotional and social supports from family and community may play an important role to improve their compliance and clinical outcomes. Therefore, diabetes support groups were developed and each support group consisted of two pharmacists, two nurses, diabetic patients and their family members. A total of 70 type 2 diabetic patient’s were enrolled and randomized into support group 1 and support group 2. Patients in the group 1 received information leaflets only, while patient in the group 2 received pharmacist counselling and information leaflets at each meeting. Patient’s awareness of diabetes and compliance with medications were assessed by a short questionnaire at baseline and final follow-up. Blood glucose and cholesterol levels were also evaluated in both groups. At the end of study, the overall patient’s awareness and compliance improved by 61.5%. The random and fasting blood glucose levels decreased over than 30% in the group 2 and around 14% in the group 1. This study reveals that collaboration between health care professionals and community in the diabetes support group might help diabetic patients to increase their knowledge and compliance with the diabetes therapy as well as glycaemic control.

An efficient computational method for a stochastic dynamic lot-sizing problem under service-level constraints

NARCIS (Netherlands)

Tarim, S.A.; Ozen, U.; Dogru, M.K.; Rossi, R.

2011-01-01

We provide an efficient computational approach to solve the mixed integer programming (MIP) model developed by Tarim and Kingsman [8] for solving a stochastic lot-sizing problem with service level constraints under the static–dynamic uncertainty strategy. The effectiveness of the proposed method

Salivary TNFα levels in groups of subjects with rheumatoid arthritis and chronic periodontitis.

Science.gov (United States)

Gamel, Ehsan B; Hashim, Nada T; Satti, Asim; Gismalla, Bakri G

2017-01-07

Rheumatoid arthritis (RA) and chronic periodontitis are the most common chronic inflammatory diseases with significant pathological and clinical similarities. Numerous studies have indicated a relationship between rheumatoid arthritis and periodontal disease. The aim of this study was to compare the TNF-α levels in saliva among patients with Rheumatoid arthritis (RA) and chronic periodontitis as well as healthy subjects. One hundred and seventy-one patients were enrolled in this cross-sectional study. Fifty-seven patients diagnosed of RA, 57 patients with chronic periodontitis and 57 healthy subjects. These patients have been examined with regard to TNF-α level from salivary samples. Their teeth were examined with regard to Plaque Index , Gingival Index, probing depth and clinical attachment level.All patients were non-smokers. The results revealed a significant difference in all periodontal parameters among the three groups. The chronic periodontitis group showed a significantly higher value in all clinical periodontal parameters in comparison to both the RA and healthy groups. No significant difference was found between salivary TNF-α level among the three study groups. Patients with chronic periodontitis had the highest periodontal indices. However there was no significant difference regarding the level of salivary TNF-α. Hence, suppression of proinflammatory cytokines might prove beneficial in suppressing periodontal diseases among RA patients.

Size-dependent energy levels of InSb quantum dots measured by scanning tunneling spectroscopy.

Science.gov (United States)

Wang, Tuo; Vaxenburg, Roman; Liu, Wenyong; Rupich, Sara M; Lifshitz, Efrat; Efros, Alexander L; Talapin, Dmitri V; Sibener, S J

2015-01-27

The electronic structure of single InSb quantum dots (QDs) with diameters between 3 and 7 nm was investigated using atomic force microscopy (AFM) and scanning tunneling spectroscopy (STS). In this size regime, InSb QDs show strong quantum confinement effects which lead to discrete energy levels on both valence and conduction band states. Decrease of the QD size increases the measured band gap and the spacing between energy levels. Multiplets of equally spaced resonance peaks are observed in the tunneling spectra. There, multiplets originate from degeneracy lifting induced by QD charging. The tunneling spectra of InSb QDs are qualitatively different from those observed in the STS of other III-V materials, for example, InAs QDs, with similar band gap energy. Theoretical calculations suggest the electron tunneling occurs through the states connected with L-valley of InSb QDs rather than through states of the Γ-valley. This observation calls for better understanding of the role of indirect valleys in strongly quantum-confined III-V nanomaterials.

Inference for binomial probability based on dependent Bernoulli random variables with applications to meta-analysis and group level studies.

Science.gov (United States)

Bakbergenuly, Ilyas; Kulinskaya, Elena; Morgenthaler, Stephan

2016-07-01

We study bias arising as a result of nonlinear transformations of random variables in random or mixed effects models and its effect on inference in group-level studies or in meta-analysis. The findings are illustrated on the example of overdispersed binomial distributions, where we demonstrate considerable biases arising from standard log-odds and arcsine transformations of the estimated probability p̂, both for single-group studies and in combining results from several groups or studies in meta-analysis. Our simulations confirm that these biases are linear in ρ, for small values of ρ, the intracluster correlation coefficient. These biases do not depend on the sample sizes or the number of studies K in a meta-analysis and result in abysmal coverage of the combined effect for large K. We also propose bias-correction for the arcsine transformation. Our simulations demonstrate that this bias-correction works well for small values of the intraclass correlation. The methods are applied to two examples of meta-analyses of prevalence. © 2016 The Authors. Biometrical Journal Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Multidimensional Recurrence Quantification Analysis (MdRQA) for the Analysis of Multidimensional Time-Series: A Software Implementation in MATLAB and Its Application to Group-Level Data in Joint Action.

Science.gov (United States)

Wallot, Sebastian; Roepstorff, Andreas; Mønster, Dan

2016-01-01

We introduce Multidimensional Recurrence Quantification Analysis (MdRQA) as a tool to analyze multidimensional time-series data. We show how MdRQA can be used to capture the dynamics of high-dimensional signals, and how MdRQA can be used to assess coupling between two or more variables. In particular, we describe applications of the method in research on joint and collective action, as it provides a coherent analysis framework to systematically investigate dynamics at different group levels-from individual dynamics, to dyadic dynamics, up to global group-level of arbitrary size. The Appendix in Supplementary Material contains a software implementation in MATLAB to calculate MdRQA measures.

The Number of Cultural Traits Is Correlated with Female Group Size but Not with Male Group Size in Chimpanzee Communities

OpenAIRE

Lind, Johan; Lindenfors, Patrik

2010-01-01

What determines the number of cultural traits present in chimpanzee (Pan troglodytes) communities is poorly understood. In humans, theoretical models suggest that the frequency of cultural traits can be predicted by population size. In chimpanzees, however, females seem to have a particularly important role as cultural carriers. Female chimpanzees use tools more frequently than males. They also spend more time with their young, skewing the infants’ potential for social learning towards their ...

Influence of food availability on the diet and activity budget of two western lowland gorilla (Gorilla gorilla gorilla) groups of differing size in the Dzanga-Ndoki National Park, Central African Republic

OpenAIRE

Neba, Terence Fuh; Donati, Giuseppe; Todd, Angelique; Masi, Shelly

2014-01-01

Variation in food availability, body size and group size are known to influence primate diet and activity budgets. Here we report how seasonal food availability shapes the diet and activity patterns of two habituated western lowland gorilla (WLG) groups of differing size. WLGs are ripe fruit opportunists, showing dietary flexibility when preferred foods are scarce. However, as fruit can be rare/ patchily distributed, as intra-group feeding competition increases with group size, access to indi...

Change and significance of serum inflammatory factors, NSE, S100 protein and stress hormone levels in patients with craniocerebral injury

Directory of Open Access Journals (Sweden)

Rui-Feng Liu

2017-09-01

Full Text Available Objective: To investigate the change and significance of serum inflammatory factors, neuron specific enolase (NSE, S100 protein and stress hormone levels in patients with brain diseases. Methods: A total of 115 patients with craniocerebral injury were selected as the observation group, according to the Glasgow Coma Scale (GCS, they were divided into light-sized group (n=38, middle-sized group (n=40 and severe-sized group (n=37, at the same time the other 120 healthy subjects were selected as the control group. The levels of serum inflammatory cytokines [tumor necrosis factor alpha (TNF-α and procalcitonin (PCT], neuron specific enolase (NSE, S100 protein and the stress hormone cortisol [(COR, adrenocorticotropic hormone (ACTH, β-endorphin (β-EP] of both groups were compared. Results: The levels of TNF-α, PCT, NSE, S100, COR, ACTH and β-EP in the observation group were (145.73±19.24 ng/L, (2.41±0.64 ng/mL, (38.11±12.28 ng/mL, (0.87±0.32 μg/L, (818.87±121.14 nmol/L, (107.38±13.94 ng/L, (126.74±39.04 ng/mL, which were significantly higher than control group, the difference was statistically significant; Comparison of indexes among the observation group, NF-α, PCT, NSE, S100, COR, ACTH and β-EP levels in the middle-sized group and severe-sized group were significantly higher than those in the light-sized group, and the levels in the severe-sized group were significantly higher than those of the middle-sized group, the difference was statistically significant. Conclusion: The levels of Serum inflammatory factors, NSE, S100 protein and stress hormone were significantly increased in patients with craniocerebral injury, the level was related to the degree of traumatic brain injury, which could be used as an important indicator to assess the severity of the disease.

Same-level fall injuries in US workplaces by age group, gender, and industry.

Science.gov (United States)

Scott, Kenneth A; Fisher, Gwenith G; Barón, Anna E; Tompa, Emile; Stallones, Lorann; DiGuiseppi, Carolyn

2018-02-01

As the workforce ages, occupational injuries from falls on the same level will increase. Some industries may be more affected than others. We conducted a cross-sectional study using data from the Bureau of Labor Statistics to estimate same-level fall injury incidence rates by age group, gender, and industry for four sectors: 1) healthcare and social assistance; 2) manufacturing; 3) retail; and 4) transportation and warehousing. We calculated rate ratios and rate differences by age group and gender. Same-level fall injury incidence rates increase with age in all four sectors. However, patterns of rate ratios and rate differences vary by age group, gender, and industry. Younger workers, men, and manufacturing workers generally have lower rates. Variation in incidence rates suggests there are unrealized opportunities to prevent same-level fall injuries. Interventions should be evaluated for their effectiveness at reducing injuries, avoiding gender- or age-discrimination and improving work ability. © 2017 Wiley Periodicals, Inc.

Decreased attention to object size information in scale errors performers.

Science.gov (United States)

Grzyb, Beata J; Cangelosi, Angelo; Cattani, Allegra; Floccia, Caroline

2017-05-01

Young children sometimes make serious attempts to perform impossible actions on miniature objects as if they were full-size objects. The existing explanations of these curious action errors assume (but never explicitly tested) children's decreased attention to object size information. This study investigated the attention to object size information in scale errors performers. Two groups of children aged 18-25 months (N=52) and 48-60 months (N=23) were tested in two consecutive tasks: an action task that replicated the original scale errors elicitation situation, and a looking task that involved watching on a computer screen actions performed with adequate to inadequate size object. Our key finding - that children performing scale errors in the action task subsequently pay less attention to size changes than non-scale errors performers in the looking task - suggests that the origins of scale errors in childhood operate already at the perceptual level, and not at the action level. Copyright © 2017 Elsevier Inc. All rights reserved.

Decoding size distribution patterns in marine and transitional water phytoplankton: from community to species level.

Directory of Open Access Journals (Sweden)

Leonilde Roselli

Full Text Available Understanding the mechanisms of phytoplankton community assembly is a fundamental issue of aquatic ecology. Here, we use field data from transitional (e.g. coastal lagoons and coastal water environments to decode patterns of phytoplankton size distribution into organization and adaptive mechanisms. Transitional waters are characterized by higher resource availability and shallower well-mixed water column than coastal marine environments. Differences in physico-chemical regime between the two environments have been hypothesized to exert contrasting selective pressures on phytoplankton cell morphology (size and shape. We tested the hypothesis focusing on resource availability (nutrients and light and mixed layer depth as ecological axes that define ecological niches of phytoplankton. We report fundamental differences in size distributions of marine and freshwater diatoms, with transitional water phytoplankton significantly smaller and with higher surface to volume ratio than marine species. Here, we hypothesize that mixing condition affecting size-dependent sinking may drive phytoplankton size and shape distributions. The interplay between shallow mixed layer depth and frequent and complete mixing of transitional waters may likely increase the competitive advantage of small phytoplankton limiting large cell fitness. The nutrient regime appears to explain the size distribution within both marine and transitional water environments, while it seem does not explain the pattern observed across the two environments. In addition, difference in light availability across the two environments appear do not explain the occurrence of asymmetric size distribution at each hierarchical level. We hypothesize that such competitive equilibria and adaptive strategies in resource exploitation may drive by organism's behavior which exploring patch resources in transitional and marine phytoplankton communities.

Cognitive load privileges memory-based over data-driven processing, not group-level over person-level processing.

Science.gov (United States)

Skorich, Daniel P; Mavor, Kenneth I

2013-09-01

In the current paper, we argue that categorization and individuation, as traditionally discussed and as experimentally operationalized, are defined in terms of two confounded underlying dimensions: a person/group dimension and a memory-based/data-driven dimension. In a series of three experiments, we unconfound these dimensions and impose a cognitive load. Across the three experiments, two with laboratory-created targets and one with participants' friends as the target, we demonstrate that cognitive load privileges memory-based over data-driven processing, not group- over person-level processing. We discuss the results in terms of their implications for conceptualizations of the categorization/individuation distinction, for the equivalence of person and group processes, for the ultimate 'purpose' and meaningfulness of group-based perception and, fundamentally, for the process of categorization, broadly defined. © 2012 The British Psychological Society.

Associations of group level popularity with observed behavior and influence in a dyadic context.

Science.gov (United States)

Lansu, Tessa A M; Cillessen, Antonius H N

2015-12-01

This study examined the association between popularity in the peer group and adolescents' behavior in a dyadic context. After collecting peer nominations for popularity, 218 early adolescents (M(age) = 11.0 years) in 109 randomly composed same-sex dyads participated in a discussion task where they planned a party for their classroom. From digital recordings of the sessions, each participant's influence, involvement, skillful leadership, coercive resource control, submissiveness, positivity, and negativity were observed. Analyses with the actor-partner interdependence model (APIM) demonstrated that for girls high group level popularity was associated with a socially sensitive interaction style and influence in the dyadic context. For both boys and girls, the interaction partner's group level popularity negatively predicted their use of coercive resource control strategies and negative behavior in the dyad. For girls, in addition, the interaction partner's group level popularity also positively predicted their submissiveness and negatively predicted their task influence. These results indicate that, in particular for girls, adolescents' group level popularity plays an important role in the behavior of both peers in a cooperative dyadic context. Copyright © 2015 Elsevier Inc. All rights reserved.

Human health no-effect levels of TiO_2 nanoparticles as a function of their primary size

International Nuclear Information System (INIS)

Laurent, Alexis; Harkema, Jack R.; Andersen, Elisabeth W.; Owsianiak, Mikołaj; Vea, Eldbjørg B.; Jolliet, Olivier

2017-01-01

As engineered nanomaterials are increasingly introduced on the market into a broad range of commodities or nanoproducts, there is a need for operational, reliable tool, enabling to consistently assess the risks and impacts associated with the releases of nanoparticles. The lack of a developed metric that accurately represents their toxic effects while capturing the influence of the most relevant physicochemical properties is one of the major impediments. Here, we investigate the relationships between the toxic responses of nano-sized and micro-sized particles in in vivo toxicological studies and their physicochemical properties. Our results for TiO_2 particles indicate statistically significant associations between the primary particle size and their toxicity responses for combined inhalation and ingestion exposure routes, although the numerical values should be considered with care due to the inability to encompass influences from other relevant physicochemical properties like surface coatings. These findings allow for expressing mass-based adverse effect levels as a continuous function of the primary size of particles. This meaningful, exploratory metric can thus be used for screening purposes and pave the way for reaching adaptive, robust risk assessments of nanomaterials, e.g. for setting up consistent threshold levels, as well as consistent life cycle assessments of nanoproducts. We provide examples of such applications.

Inference for binomial probability based on dependent Bernoulli random variables with applications to meta‐analysis and group level studies

Science.gov (United States)

Bakbergenuly, Ilyas; Morgenthaler, Stephan

2016-01-01

We study bias arising as a result of nonlinear transformations of random variables in random or mixed effects models and its effect on inference in group‐level studies or in meta‐analysis. The findings are illustrated on the example of overdispersed binomial distributions, where we demonstrate considerable biases arising from standard log‐odds and arcsine transformations of the estimated probability p^, both for single‐group studies and in combining results from several groups or studies in meta‐analysis. Our simulations confirm that these biases are linear in ρ, for small values of ρ, the intracluster correlation coefficient. These biases do not depend on the sample sizes or the number of studies K in a meta‐analysis and result in abysmal coverage of the combined effect for large K. We also propose bias‐correction for the arcsine transformation. Our simulations demonstrate that this bias‐correction works well for small values of the intraclass correlation. The methods are applied to two examples of meta‐analyses of prevalence. PMID:27192062

Bias and power in group-based epidemiologic studies of low-back pain exposure and outcome--effects of study size and exposure measurement efforts.

Science.gov (United States)

Coenen, Pieter; Mathiassen, Svend Erik; Kingma, Idsart; Boot, Cécile R L; Bongers, Paulien M; van Dieën, Jaap H

2015-05-01

Exposure-outcome studies, for instance on work-related low-back pain (LBP), often classify workers into groups for which exposures are estimated from measurements on a sample of workers within or outside the specific study. The present study investigated the influence on bias and power in exposure-outcome associations of the sizes of the total study population and the sample used to estimate exposures. At baseline, lifting, trunk flexion, and trunk rotation were observed for 371 of 1131 workers allocated to 19 a-priori defined occupational groups. LBP (dichotomous) was reported by all workers during 3 years of follow-up. All three exposures were associated with LBP in this parent study (P power (P power >0.80 (P level = 0.05). A similar performance required n ≥ 30 workers for rotated trunk. Small numbers of observed workers (k) resulted in biased OR, while power was, in general, more sensitive to the total number of workers (n). In epidemiologic studies using a group-based exposure assessment strategy, statistical performance may be sufficient if outcome is obtained from a reasonably large number of workers, even if exposure is estimated from only few workers per group. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Effect of group size on performance and egg quality of laying hens during 20 to 36 weeks of age

Directory of Open Access Journals (Sweden)

Fulvia Bovera

2014-03-01

Full Text Available The aim of this study was to improve knowledge on the effect of group size on productive performance and egg quality of hens raised in furnished cages equally designed. A total of 520, 15-week-old Lohmann Brown laying hens were divided into 2 groups to have a similar initial body weight (average 1392±16.3 g. The cages of S25 group (240 L x 78 W x 50 H cm, 749 cm2/hen hosted a total of 200 hens, while those of S40 group (462 L x 65 W x 50 H, 751 cm2/hen included 320 birds. Experimental data were recorded after an adaptation period of 5 weeks (20 to 36 weeks of age. Hens were submitted to 15 h of light/d. The average temperature inside the building was 24.6±2.5°C over the entire experimental period with higher values at 24, 26, 28 and 30 weeks of age. The relative humidity recorded inside the building was 55% at week 20 and 60% all through the experimental period. Hens raised from S40 group had lower percentage of egg production (84.91 vs 88.90%, P<0.01 and higher feed conversion ratio (2.70 vs 2.25, P<0.0001 than S25 group. The percentage of eggs laid out of the nest was higher in S25 than S40 group (0.26 vs 0.19%, P<0.01. As expected, the week of age affected almost all the parameters (feed intake, body weight, laying percentage, egg weight, yolk, shell and albumen indexes, shell thickness, Haugh unit. However, the effect of group size was particularly evident during the hot period.

Mercury levels in defined Italian population groups

International Nuclear Information System (INIS)

Ingrao, G.; Belloni, P.

1991-01-01

Our group conducts its research activity in the Department AMB-BIO (Biological and Sanitary Effect of Toxic Agents) of ENEA (National Committee for Research and Development of Nuclear and Alternative Energy) at the research centre of Casaccia. The food chain is the main pathway leading to humans for most of the trace elements. The research, therefore, has been directed mainly towards the study of the variability of the trace element content in the Italian diet. This programme aims at assessing the adequacy of the essential trace elements ingestion, and to verify that the ingestion of toxic trace elements is below the recommended values. Part of this research was conducted in the frame of the IAEA CRP on ''Human daily Intakes of Nutritionally Important Trace Elements as Measured by Nuclear and Other Techniques''. Studies carried out by the National Institute of Nutrition and FAO have shown that there are some population groups having a fish consumption significantly higher than the average value for the Italian population. These groups are usually found in coastal towns were fishing is one of the main occupation and generally includes fishermen, fish dealers, restaurant workers and their families. A pilot study was conducted in one of these towns, Bagnara Calabra in the South of Italy, where the average fish consumption is 27.1 kg per year, which is more than twice the national average. The results have shown that the mercury concentration in the diet is significantly higher than in other Italian locations, the mercury levels in blood and hair sample in these subjects are also significantly higher than the values reported for subjects of the general Italian population. 6 refs

Reservoir water level forecasting using group method of data handling

Science.gov (United States)

Zaji, Amir Hossein; Bonakdari, Hossein; Gharabaghi, Bahram

2018-06-01

Accurately forecasted reservoir water level is among the most vital data for efficient reservoir structure design and management. In this study, the group method of data handling is combined with the minimum description length method to develop a very practical and functional model for predicting reservoir water levels. The models' performance is evaluated using two groups of input combinations based on recent days and recent weeks. Four different input combinations are considered in total. The data collected from Chahnimeh#1 Reservoir in eastern Iran are used for model training and validation. To assess the models' applicability in practical situations, the models are made to predict a non-observed dataset for the nearby Chahnimeh#4 Reservoir. According to the results, input combinations (L, L -1) and (L, L -1, L -12) for recent days with root-mean-squared error (RMSE) of 0.3478 and 0.3767, respectively, outperform input combinations (L, L -7) and (L, L -7, L -14) for recent weeks with RMSE of 0.3866 and 0.4378, respectively, with the dataset from https://www.typingclub.com/st. Accordingly, (L, L -1) is selected as the best input combination for making 7-day ahead predictions of reservoir water levels.

Why Do Militant Groups Experience Intra-organizational Conflict

Science.gov (United States)

2016-12-01

and state features as the size of groups, ethnic cohesion strength, and democratic or autocratic nature of the government. Their primary finding is...leadership can also increase organizational dysfunction and conflict, where sub-group leaders can play two-level games30 such as tactically preserving...that identifies itself as a movement to fight against unfair oppression of a minority group might have a difficult time justifying its own autocratic

Big Five personality group differences across academic majors

DEFF Research Database (Denmark)

Vedel, Anna

characterisations are more than humoristic elements in TV shows; are there real, measurable personality differences among groups of academics? One way to study this is to look at students in different academic majors and examine whether they differ on the group level in broad personality traits. During the past...... decades, studies have regularly explored associations between enrolment in specific academic majors and scores on the Big Five personality traits; Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness. The present review examines this research systematically, summarises group...... group differences in the Big Five personality traits were generally found in the included studies. None of the included studies reported effect sizes, though, so the magnitude of the obtained differences was not estimated. Consequently, effect sizes were calculated using means and standard deviations...

Warring arthropod societies: Social spider colonies can delay annihilation by predatory ants via reduced apparency and increased group size.

Science.gov (United States)

Keiser, Carl N; Wright, Colin M; Pruitt, Jonathan N

2015-10-01

Sociality provides individuals with benefits via collective foraging and anti-predator defense. One of the costs of living in large groups, however, is increased apparency to natural enemies. Here, we test how the individual-level and collective traits of spider societies can increase the risk of discovery and death by predatory ants. We transplanted colonies of the social spider Stegodyphus dumicola into a habitat dense with one of their top predators, the pugnacious ant Anoplolepis custodiens. With three different experiments, we test how colony-wide survivorship in a predator-dense habitat can be altered by colony apparency (i.e., the presence of a capture web), group size, and group composition (i.e., the proportion of bold and shy personality types present). We also test how spiders' social context (i.e., living solitarily vs. among conspecifics) modifies their behaviour toward ants in their capture web. Colonies with capture webs intact were discovered by predatory ants on average 25% faster than colonies with the capture web removed, and all discovered colonies eventually collapsed and succumbed to predation. However, the lag time from discovery by ants to colony collapse was greater for colonies containing more individuals. The composition of individual personality types in the group had no influence on survivorship. Spiders in a social group were more likely to approach ants caught in their web than were isolated spiders. Isolated spiders were more likely to attack a safe prey item (a moth) than they were to attack ants and were more likely to retreat from ants after contact than they were after contact with moths. Together, our data suggest that the physical structures produced by large animal societies can increase their apparency to natural enemies, though larger groups can facilitate a longer lag time between discovery and demise. Lastly, the interaction between spiders and predatory ants seems to depend on the social context in which spiders reside

Collective motion of groups of self-propelled particles following interacting leaders

Science.gov (United States)

Ferdinandy, B.; Ozogány, K.; Vicsek, T.

2017-08-01

In order to keep their cohesiveness during locomotion gregarious animals must make collective decisions. Many species boast complex societies with multiple levels of communities. A common case is when two dominant levels exist, one corresponding to leaders and the other consisting of followers. In this paper we study the collective motion of such two-level assemblies of self-propelled particles. We present a model adapted from one originally proposed to describe the movement of cells resulting in a smoothly varying coherent motion. We shall use the terminology corresponding to large groups of some mammals where leaders and followers form a group called a harem. We study the emergence (self-organization) of sub-groups within a herd during locomotion by computer simulations. The resulting processes are compared with our prior observations of a Przewalski horse herd (Hortobágy, Hungary) which we use as results from a published case study. We find that the model reproduces key features of a herd composed of harems moving on open ground, including fights for followers between leaders and bachelor groups (group of leaders without followers). One of our findings, however, does not agree with the observations. While in our model the emerging group size distribution is normal, the group size distribution of the observed herd based on historical data have been found to follow lognormal distribution. We argue that this indicates that the formation (and the size) of the harems must involve a more complex social topology than simple spatial-distance based interactions.

Association of ABO blood groups with diabetes mellitus

African Journals Online (AJOL)

2010-02-08

Feb 8, 2010 ... We studied the association of ABO blood groups with DM type 2. Patients and methodology: It was ... dent diabetes mellitus (NIDDM or type 2), characterized by elevated insulin levels ... diabetic ketoacidosis. Sample size was ...

Measuring and modeling the interaction among reward size, delay to reward, and satiation level on motivation in monkeys.

Science.gov (United States)

Minamimoto, Takafumi; La Camera, Giancarlo; Richmond, Barry J

2009-01-01

Motivation is usually inferred from the likelihood or the intensity with which behavior is carried out. It is sensitive to external factors (e.g., the identity, amount, and timing of a rewarding outcome) and internal factors (e.g., hunger or thirst). We trained macaque monkeys to perform a nonchoice instrumental task (a sequential red-green color discrimination) while manipulating two external factors: reward size and delay-to-reward. We also inferred the state of one internal factor, level of satiation, by monitoring the accumulated reward. A visual cue indicated the forthcoming reward size and delay-to-reward in each trial. The fraction of trials completed correctly by the monkeys increased linearly with reward size and was hyperbolically discounted by delay-to-reward duration, relations that are similar to those found in free operant and choice tasks. The fraction of correct trials also decreased progressively as a function of the satiation level. Similar (albeit noiser) relations were obtained for reaction times. The combined effect of reward size, delay-to-reward, and satiation level on the proportion of correct trials is well described as a multiplication of the effects of the single factors when each factor is examined alone. These results provide a quantitative account of the interaction of external and internal factors on instrumental behavior, and allow us to extend the concept of subjective value of a rewarding outcome, usually confined to external factors, to account also for slow changes in the internal drive of the subject.

The Process and Experience of Online Group Counseling for Masters-Level Counseling Students

Science.gov (United States)

Lopresti, Jason Michael

2010-01-01

The present study explored the process and experience of online group counseling using a text-based synchronous program, particularly addressing how the process compares to face-to-face group counseling. Six students in a masters-level group counseling class voluntarily chose to participate for eight sixty minute online sessions on a weekly basis,…

Impact of lipoprotein(a) levels and apolipoprotein(a) isoform size on risk of coronary heart disease

NARCIS (Netherlands)

Hopewell, J. C.; Seedorf, U.; Farrall, M.; Parish, S.; Kyriakou, T.; Goel, A.; Hamsten, A.; Collins, R.; Watkins, H.; Clarke, R.; van der Hout, Annemarie H.

Objectives. Observational and genetic studies have shown that lipoprotein(a) [Lp(a)] levels and apolipoprotein( a) [apo(a)] isoform size are both associated with coronary heart disease (CHD) risk, but the relative independence of these risk factors remains unclear. Clarification of this uncertainty

Effects of dietary calcium levels and limestone particicle size on the performance, tibia and blood of laying hens

Directory of Open Access Journals (Sweden)

K Pelicia

2011-03-01

Full Text Available A total of 405 23-week-old ISA® Brown layers were distributed in a completely randomized experimental design in a factorial arrangement with nine treatments consisting of three dietary calcium levels (3.5, 3.75, and 4.5% and three limestone particle sizes (100% fine limestone (FL, 70% FL + 30% coarse limestone (CL and 50% (FL + 50% (CL, with nine replicates of five birds per cage. The following parameters were evaluated: percentage of lay, defective eggs, egg weight, egg mass, feed intake, feed conversion ratio (per kg eggs and per dozen eggs, and mortality. Dietary Ca levels significantly affected lay, with birds fed diets containing 4.5% calcium producing less eggs as compared to those fed 3.0 and 3.75% Ca. Egg production linearly decreased as dietary Ca levels increased, but blood Ca levels (mg/L increased in 28-week-old birds. The interaction of dietary Ca levels and limestone particle sizes resulted in a reduction in tibial ash Ca content as dietary Ca levels increased and as fine limestone was replaced by coarse limestone. It is concluded that a dietary Ca level of 3.75% and 100% fine particle limestone are required to maintain adequate egg production and available Ca blood level.

The Influence of Daily Stress on Sedentary Behavior: Group and Person (N of 1) Level Results of a 1-Year Observational Study.

Science.gov (United States)

Diaz, Keith M; Thanataveerat, Anusorn; Parsons, Faith E; Yoon, Sunmoo; Cheung, Ying Kuen; Alcantara, Carmela; Duran, Andrea T; Ensari, Ipek; Krupka, David J; Schwartz, Joseph E; Burg, Matthew M; Davidson, Karina W

2018-05-24

The purpose of this study, which used mobile technologies to continuously collect data over 1 year, was to examine the association of psychological stress with objectively measured sedentary behavior in adults at both the group (e.g. nomothetic approach) and individual (e.g. idiographic approach) level. Data were collected in an observational study of healthy adults (n=79) residing in the New York City metro area who were studied for 365 days from 2014-2015. Sedentary behavior was objectively measured via accelerometry. A smartphone-based electronic diary was used to assess level of stress ("Overall, how stressful was your day?"; 0-10 scale) and sources of stress. The end-of-day stress rating was not associated with total sedentary time (B= -1.34, p=0.767) at the group-level. When specific sources of stress were evaluated at the group-level, argument-related stress was associated with increased sedentariness; while running late- and work-related stress were associated with decreased sedentariness. There was a substantial degree of inter-individual variability in the relationship of stress with sedentary behavior. Both the level and sources of stress were associated with increased sedentariness for some, decreased sedentariness for others, and had no effect for many (within-person variance p-value stress on sedentary behavior varies by source of stress and from person-to-person. A precision medicine approach may be warranted to target reductions in sedentary time; although further studies are needed to confirm the observed findings in light of study limitations including a small sample size and enrollment of participants from a single, urban metropolitan area.

Social Class and Group Size as Predictors of Behavior in Male Equus kiang

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Prameek M. Kannan

2017-11-01

Full Text Available Ethograms provide a systematic approach to identify and quantify the repertoire of behaviors of an organism. This information may assist animal welfare in zoos, increase awareness of conservation needs, and help curb high-risk behaviors during human-wildlife conflict. Our primary objective was to utilize an equid ethogram to produce activity budgets for Equus kiang males, a social ungulate that is among the least-studied mammals worldwide, and unknown to the ethological literature. We recently reported the existence of three social classes of this species; Territorial males, Bachelor males and ‘Transient’ males. Therefore, our secondary objective was to compare activity budgets in each of these three groups. We found that kiang spent >70% of their time performing six behaviors: vigilance (34%, locomotion (24.2%, resting (14.2%, mixed foraging (12.5%, browsing (5.1%, and antagonism (1.1%. Over 2% of the total behavioral investment was spent on olfactory investigations (genital sniffing, sniffing proximity and flehmen. Eleven of the eighteen behaviors differed by class. Habitat selection differed strongly by each group, with Territorial males favoring mesic sites with greater vegetation abundance. Vigilance also differed according to habitat selection, but not group size. Animals in the xeric, least vegetation-rich area were far less vigilant than animals at more attractive sites. We found that the full repertoire of behaviors, and relative investments in each, differ according to social class. These findings are a reminder that researchers should make every effort to disambiguate social class among ungulates– and other taxa where behaviors are class-dependent.

Social groups preferences relation to motivations and ability levels of whitewater kayakers

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Seth Turner; Rod Zwick

2002-01-01

Social groups play an important role in many adventure recreation activities. The purpose of this study was to examine the social group preference relation to motives and ability levels of whitewater kayakers. When participants go out on a kayaking trip they are seeking varying degrees of experiences, a major contributor to that experience comes from the members of...

INCREASED VASOOCCLUSIVE CRISIS IN “O” BLOOD GROUP SICKLE CELL DISEASE PATIENTS: ASSOCIATION WITH UNDERLYING THROMBOSPONDIN LEVELS.

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M. Al Huneini

2017-04-01

Full Text Available Abstract: Objectives: To explore the incidence of vaso-occlusive crisis (VOC in Blood Group “O” sickle cell disease (SCD patients, and correlate it with the blood group and thrombospondin (TSP levels. Methods: In 89 consecutive SCD patients, blood samples were obtained for vWF antigen, collagen binding activity, blood group typing, C-reactive protein, variant hemoglobin analysis (HPLC, Serum TSP 1 and TSP 2 levels, complete blood counts, liver function tests, LDH and renal function tests during VOC episodes and in steady state conditions. Results: In the steady state SCD patients (n=72, “O” blood group patients (n=37 showed significantly higher median serum TSP 1 and TSP 2 levels than the non “O” blood group patients [n=35] [p <0.05, Mann-Whitney test], with an inverse relation between VWF:Ag, Factor VIII:C and TSP levels. Furthermore, the serum TSP 1 and TSP 2 levels were significantly higher in patients presenting with acute VOC [n=17], and in those with repeated VOC’s (group 1, n=16 especially amongst those patients with blood group “O” [p, <0.05, Mann-Whitney test]. Conclusions: The study shows that there was an inverse relation between TSP and vWF levels, in blood group “O” SCD patients with an upregulation of the TSP levels. Expectedly, during active VOC crisis, the TSP 1 and TSP 2 levels were significantly elevated.    Key Words: VOC; SCD; TSP; vWD; Blood groups

The oxidative costs of reproduction are group-size dependent in a wild cooperative breeder.

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Cram, Dominic L; Blount, Jonathan D; Young, Andrew J

2015-11-22

Life-history theory assumes that reproduction entails a cost, and research on cooperatively breeding societies suggests that the cooperative sharing of workloads can reduce this cost. However, the physiological mechanisms that underpin both the costs of reproduction and the benefits of cooperation remain poorly understood. It has been hypothesized that reproductive costs may arise in part from oxidative stress, as reproductive investment may elevate exposure to reactive oxygen species, compromising survival and future reproduction and accelerating senescence. However, experimental evidence of oxidative costs of reproduction in the wild remains scarce. Here, we use a clutch-removal experiment to investigate the oxidative costs of reproduction in a wild cooperatively breeding bird, the white-browed sparrow weaver, Plocepasser mahali. Our results reveal costs of reproduction that are dependent on group size: relative to individuals in groups whose eggs were experimentally removed, individuals in groups that raised offspring experienced an associated cost (elevated oxidative damage and reduced body mass), but only if they were in small groups containing fewer or no helpers. Furthermore, during nestling provisioning, individuals that provisioned at higher rates showed greater within-individual declines in body mass and antioxidant protection. Our results provide rare experimental evidence that reproduction can negatively impact both oxidative status and body mass in the wild, and suggest that these costs can be mitigated in cooperative societies by the presence of additional helpers. These findings have implications for our understanding of the energetic and oxidative costs of reproduction, and the benefits of cooperation in animal societies. © 2015 The Authors.

COMPARISON OF LEVELS OF SELF-ESTEEM BY SEX AND LEVEL OF PHYSICAL ACTIVITY IN TWO GROUPS OF SENIOR ADULTS

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Diego Rodríguez Méndez

2016-08-01

Full Text Available The purpose of this study is to observe whether there are differences in the self-esteem score, depending on the level of physical activity (active-sedentary in a sample of senior adults. Twenty-six senior adults participated in the study with an average of 73 ± 9 years of age. The sedentary group (n = 12 belonged to the Santo Domingo Nursing Home in Heredia, Costa Rica, while the active group belonged to the project entitled Modulation of the Aging Process of the Movement for Life Program. Results: No significant differences were found in scores by level of physical activity (t = 0.931, p = 0.363; however, there were significant differences in self-esteem scores by gender (t = -2.255, p = 0.034. It was concluded that the level of physical activity does not affect self-esteem and that men’s level of self-esteem is higher than women’s.

Optically-derived estimates of phytoplankton size class and taxonomic group biomass in the Eastern Subarctic Pacific Ocean

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Zeng, Chen; Rosengard, Sarah Z.; Burt, William; Peña, M. Angelica; Nemcek, Nina; Zeng, Tao; Arrigo, Kevin R.; Tortell, Philippe D.

2018-06-01

We evaluate several algorithms for the estimation of phytoplankton size class (PSC) and functional type (PFT) biomass from ship-based optical measurements in the Subarctic Northeast Pacific Ocean. Using underway measurements of particulate absorption and backscatter in surface waters, we derived estimates of PSC/PFT based on chlorophyll-a concentrations (Chl-a), particulate absorption spectra and the wavelength dependence of particulate backscatter. Optically-derived [Chl-a] and phytoplankton absorption measurements were validated against discrete calibration samples, while the derived PSC/PFT estimates were validated using size-fractionated Chl-a measurements and HPLC analysis of diagnostic photosynthetic pigments (DPA). Our results showflo that PSC/PFT algorithms based on [Chl-a] and particulate absorption spectra performed significantly better than the backscatter slope approach. These two more successful algorithms yielded estimates of phytoplankton size classes that agreed well with HPLC-derived DPA estimates (RMSE = 12.9%, and 16.6%, respectively) across a range of hydrographic and productivity regimes. Moreover, the [Chl-a] algorithm produced PSC estimates that agreed well with size-fractionated [Chl-a] measurements, and estimates of the biomass of specific phytoplankton groups that were consistent with values derived from HPLC. Based on these results, we suggest that simple [Chl-a] measurements should be more fully exploited to improve the classification of phytoplankton assemblages in the Northeast Pacific Ocean.

Productivity, trophic levels and size spectra of zooplankton in northern Norwegian shelf regions

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Zhou, Meng; Tande, Kurt S.; Zhu, Yiwu; Basedow, Sünnje

2009-10-01

Many studies have been conducted in northern Norwegian shelf regions to assess distributions and abundances of zooplankton in the last decade using towed Scanfish-conductivity, temperature and depth sensors (CTD)-optical plankton counter (OPC), and plankton nets. Significant progresses have been made in understanding dominant species, life histories and behavior, and in using size-structured data to identify dominant species in a certain size range. Using these Scanfish-CTD-OPC data, the analysis of zooplankton community size structures, compositions and their relationships with water types is made along the shelf region from Lofoten, North Cape to Varangerfjorden. From the relationships between the water types and zooplankton communities, the transports and exchanges of zooplankton communities between the Norwegian Coastal and Norwegian Atlantic Waters in regions near Malangsgrunnen and Nordvestbanken are examined. The biovolume (biomass) spectra are further analyzed for the productivity, trophic levels and seasonality of communities in these regions, indicating a steeper slope of the biovolume spectrum for a community dominated by herbivorous species in spring and a flatter slope for a community dominated by carnivorous-omnivorous species in winter. The comparison with the zooplankton biovolume spectra obtained in areas west of Antarctic Peninsula is made to examine and understand the differences in the zooplankton biovolume spectra, their trophic dynamics and potential human impacts between different regions.

Grain size statistics and depositional pattern of the Ecca Group sandstones, Karoo Supergroup in the Eastern Cape Province, South Africa

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Baiyegunhi Christopher

2017-11-01

Full Text Available Grain size analysis is a vital sedimentological tool used to unravel the hydrodynamic conditions, mode of transportation and deposition of detrital sediments. In this study, detailed grain-size analysis was carried out on thirty-five sandstone samples from the Ecca Group in the Eastern Cape Province of South Africa. Grain-size statistical parameters, bivariate analysis, linear discriminate functions, Passega diagrams and log-probability curves were used to reveal the depositional processes, sedimentation mechanisms, hydrodynamic energy conditions and to discriminate different depositional environments. The grain-size parameters show that most of the sandstones are very fine to fine grained, moderately well sorted, mostly near-symmetrical and mesokurtic in nature. The abundance of very fine to fine grained sandstones indicate the dominance of low energy environment. The bivariate plots show that the samples are mostly grouped, except for the Prince Albert samples that show scattered trend, which is due to the either mixture of two modes in equal proportion in bimodal sediments or good sorting in unimodal sediments. The linear discriminant function analysis is dominantly indicative of turbidity current deposits under shallow marine environments for samples from the Prince Albert, Collingham and Ripon Formations, while those samples from the Fort Brown Formation are lacustrine or deltaic deposits. The C-M plots indicated that the sediments were deposited mainly by suspension and saltation, and graded suspension. Visher diagrams show that saltation is the major process of transportation, followed by suspension.

Grain size statistics and depositional pattern of the Ecca Group sandstones, Karoo Supergroup in the Eastern Cape Province, South Africa

Science.gov (United States)

Baiyegunhi, Christopher; Liu, Kuiwu; Gwavava, Oswald

2017-11-01

Grain size analysis is a vital sedimentological tool used to unravel the hydrodynamic conditions, mode of transportation and deposition of detrital sediments. In this study, detailed grain-size analysis was carried out on thirty-five sandstone samples from the Ecca Group in the Eastern Cape Province of South Africa. Grain-size statistical parameters, bivariate analysis, linear discriminate functions, Passega diagrams and log-probability curves were used to reveal the depositional processes, sedimentation mechanisms, hydrodynamic energy conditions and to discriminate different depositional environments. The grain-size parameters show that most of the sandstones are very fine to fine grained, moderately well sorted, mostly near-symmetrical and mesokurtic in nature. The abundance of very fine to fine grained sandstones indicate the dominance of low energy environment. The bivariate plots show that the samples are mostly grouped, except for the Prince Albert samples that show scattered trend, which is due to the either mixture of two modes in equal proportion in bimodal sediments or good sorting in unimodal sediments. The linear discriminant function analysis is dominantly indicative of turbidity current deposits under shallow marine environments for samples from the Prince Albert, Collingham and Ripon Formations, while those samples from the Fort Brown Formation are lacustrine or deltaic deposits. The C-M plots indicated that the sediments were deposited mainly by suspension and saltation, and graded suspension. Visher diagrams show that saltation is the major process of transportation, followed by suspension.

Effect of caliber size and fat level on the inactivation of E. coli O157:H7 in dry fermented sausages.

Science.gov (United States)

De Souza, James; Ahmed, Rafath; Strange, Philip; Barbut, Shai; Balamurugan, S

2018-02-02

Dry fermented sausages (DFS) have been subject to numerous validation studies, as pathogen reduction heavily relies on both ingredients and processing. In this study the effect of product caliber size (32, 55, 80mm), and fat level (low, 9.67%; high, 18.46% wt/wt) on the inactivation of E. coli O157:H7 during DFS production was examined. Sausages containing a five-strain cocktail of E. coli O157:H7 at 10 7 CFU/g were manufactured and monitored for changes in physicochemical properties and inoculated E. coli O157:H7 numbers were enumerated during the DFS production stages and log reduction rates were calculated. Significant (P0.05) different among sausages of different caliber size or fat levels. No significant (P>0.05) reduction in a w was observed during fermentation of the sausages. However, during the drying phase, sausages with larger caliber sizes required a significantly longer duration of drying to achieve the same a w of smaller caliber size sausages. For instance, to achieve an a w of ≤0.9, following 5days of fermentation/curing, 80mm caliber sausages required up to 27days of drying compared with 13 and 6days for 55 and 32mm caliber size sausages, respectively. Fat levels on the other hand did not significantly (P>0.05) effect the reduction of a w during drying of the sausages. During the fermentation stage there was a significant and rapid reduction in E. coli O157:H7 counts by about 1.1- to 1.4-log units, but was not significantly different among sausages of different caliber size and fat levels. Considering the whole process, only caliber size had a significant effect on log reduction of E. coli O157:H7. ANOVA of log reduction rates of E. coli O157:H7 among sausages of different caliber size and fat levels revealed no significant differences during the fermentation, however, during the drying of the sausages, log reduction rate of E. coli O157:H7 was significantly (PE. coli O157:H7 in high fat large caliber sausages was the lowest at -0.082±0.004 log

A Multi Size-Level Assessment of Benthic Marine Communities in a Coastal Environment: Are They Different Sides of the Same Coin?

DEFF Research Database (Denmark)

Vannini, Claudia; Volpi, Marta; Lardicci, Claudio

2015-01-01

Organism body size has been demonstrated to be a discriminating element in shaping the response of living beings to environmental factors, thus playing a fundamental role in community structuring. Despite the importance of studies elucidating relations among communities of different size levels...... have no (or very low) influence on the community composition at other size-levels. Moreover, each community responds in a different way to the environmental parameters and with a degree of sensitivity which seems to increase with organism size. Therefore, our data indicate that the characterization...... in ecosystems, the attempts that have been made in this sense are still very scarce and a reliable approach for these research still has to be defined. We characterized the benthic communities of bacteria, microbial eukaryotes, meiofauna and macrofauna in a coastal environment, encompassing a 10000-fold...

HBA1C AND LIPID PROFILE LEVELS IN THE KNOWN TYPE 2 DIABETIC GROUP IN THE RURAL REGION OF VIDARBHA, MAHARASHTRA, INDIA

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Sarmistha Sarkar

2017-04-01

Full Text Available BACKGROUND Diabetes Mellitus (DM is a group of metabolic diseases in which there is high blood sugar levels over a prolonged period of time, and if early interventions are not taken, then it can cause many life-threatening complications like heart disease, stroke, kidney failure, damage to eyes, etc. Our aim is to determine HbA1c and Lipid profile level in the known type 2 diabetic group in the rural region of Vidarbha, Maharashtra, India, to see that as our study is a rural-based study and there is less pollution and stress factor compared to the cities whether it effects out study result or not. MATERIALS AND METHODS FBS, HbA1c, TC, HDL, LDL, VLDL, TG levels were evaluated. Total sample size 60 in between 30-40 years including males and females divided into two groups. 30 patients study group with known history of type 2 DM who attended the Medicine OPD and 30 age, sex matched healthy controls. Statistical analysis was done by using SPSS 17.0 version. RESULTS Results of serum lipid profile showed that mean values for TC, TG, HDL, LDL and VLDL in study group were 227.76±30.72, 152.23 ± 40.94, 40.5 ± 6.43, 153.30 ± 27.70 and 33.00 ± 9.94 mg/dL. FBS showed significant positive correlation with HbA1c (p<0.002. HDL has significant negative correlation with HbA1c (p<0.008. CONCLUSION Early detection in the abnormalities of serum lipid profile and HbA1c can minimise the risk for micro and macroangiopathies in the known type 2 diabetic patients.

Replication analysis of genetic association of the NCAN-CILP2 region with plasma lipid levels and non-alcoholic fatty liver disease in Asian and Pacific ethnic groups.

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Boonvisut, Supichaya; Nakayama, Kazuhiro; Makishima, Saho; Watanabe, Kazuhisa; Miyashita, Hiroshi; Lkhagvasuren, Munkhtulga; Kagawa, Yasuo; Iwamoto, Sadahiko

2016-01-13

The Neurocan-cartilage intermediate layer protein 2 (NCAN-CILP2) region forms a tight linkage disequilibrium (LD) block and is associated with plasma lipid levels and non-alcoholic fatty liver disease (NAFLD) in individuals of European descent but not in the Malay and Japanese ethnic groups. Recent genome-wide resequence studies identified a missense single-nucleotide polymorphism (SNP) (rs58542926) of the transmembrane 6 superfamily member 2 (TM6SF2) gene in the NCAN-CILP2 region related to hepatic triglyceride content. This study aims to analyze the influences of SNPs in this region on NAFLD and plasma lipid levels in the Asian and Pacific ethnic groups and to reveal the reasons behind positive and negative genetic associations dependent on ethnicity. Samples and characteristic data were collected from 3,013 Japanese, 119 Palauan, 947 Mongolian, 212 Thai and 401 Chinese people. Hepatic sonography data was obtained from the Japanese individuals. Genotyping data of five SNPs, rs58542926, rs735273, rs1009136, rs1858999, and rs16996148, were used to verify the effect on serum lipid levels by multiple linear regression, and the association with NAFLD in the Japanese population was examined by logistic regression analysis. rs58542926 showed significant association with the plasma triglyceride (TG) level in Japanese (P = 0.0009, effect size = 9.5 (± 3.25) mg/dl/allele) and Thai (P = 0.0008, effect size = 31.6 (± 11.7) mg/dl/allele) study subjects. In Mongolian individuals, there was a significant association of rs58542926 with total cholesterol level (P = 0.0003, 11.7 (± 3.2) mg/dl/allele) but not with TG level. In multiple comparisons in Chinese individuals, rs58542926 was weakly (P = 0.022) associated with TG levels, although the threshold for statistical significance was not reached. In Palauan individuals, there was no significant association with the studied SNPs. rs58542926 also showed significant association with Japanese NAFLD. The minor allele (t) increased

Genome Size Diversity and Its Impact on the Evolution of Land Plants

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Jaume Pellicer

2018-02-01

Full Text Available Genome size is a biodiversity trait that shows staggering diversity across eukaryotes, varying over 64,000-fold. Of all major taxonomic groups, land plants stand out due to their staggering genome size diversity, ranging ca. 2400-fold. As our understanding of the implications and significance of this remarkable genome size diversity in land plants grows, it is becoming increasingly evident that this trait plays not only an important role in shaping the evolution of plant genomes, but also in influencing plant community assemblages at the ecosystem level. Recent advances and improvements in novel sequencing technologies, as well as analytical tools, make it possible to gain critical insights into the genomic and epigenetic mechanisms underpinning genome size changes. In this review we provide an overview of our current understanding of genome size diversity across the different land plant groups, its implications on the biology of the genome and what future directions need to be addressed to fill key knowledge gaps.

Behavioral and physiological responses to subgroup size and number of people in howler monkeys inhabiting a forest fragment used for nature-based tourism.

Science.gov (United States)

Aguilar-Melo, Adriana R; Andresen, Ellen; Cristóbal-Azkarate, Jurgi; Arroyo-Rodríguez, Victor; Chavira, Roberto; Schondube, Jorge; Serio-Silva, Juan Carlos; Cuarón, Alfredo D

2013-11-01

Animals' responses to potentially threatening factors can provide important information for their conservation. Group size and human presence are potentially threatening factors to primates inhabiting small reserves used for recreation. We tested these hypotheses by evaluating behavioral and physiological responses in two groups of mantled howler monkeys (Alouatta palliata mexicana) at the "Centro Ecológico y Recreativo El Zapotal", a recreational forest reserve and zoo located in the Mexican state of Chiapas. Both groups presented fission-fusion dynamics, splitting into foraging subgroups which varied in size among, but not within days. Neither subgroup size nor number of people had an effect on fecal cortisol. Out of 16 behavioral response variables tested, the studied factors had effects on six: four were affected by subgroup size and two were affected by number of people. With increasing subgroup size, monkeys increased daily path lengths, rested less, increased foraging effort, and used more plant individuals for feeding. As the number of people increased, monkeys spent more time in lower-quality habitat, and less time engaged in social interactions. Although fecal cortisol levels were not affected by the factors studied, one of the monkey groups had almost twice the level of cortisol compared to the other group. The group with higher cortisol levels also spent significantly more time in the lower-quality habitat, compared to the other group. Our results suggest that particular behavioral adjustments might allow howler monkeys at El Zapotal to avoid physiological stress due to subgroup size and number of people. However, the fact that one of the monkey groups is showing increased cortisol levels may be interpreted as a warning sign, indicating that an adjustment threshold is being reached, at least for part of the howler monkey population in this forest fragment. © 2013 Wiley Periodicals, Inc.

Human health no-effect levels of TiO{sub 2} nanoparticles as a function of their primary size

Energy Technology Data Exchange (ETDEWEB)

Laurent, Alexis, E-mail: alau@dtu.dk [Technical University of Denmark, Division for Quantitative Sustainability Assessment, Department of Management Engineering (Denmark); Harkema, Jack R. [Michigan State University, Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine (United States); Andersen, Elisabeth W. [Technical University of Denmark, Statistics and Data Analysis Section, Department of Applied Mathematics and Computer Science (Denmark); Owsianiak, Mikołaj; Vea, Eldbjørg B. [Technical University of Denmark, Division for Quantitative Sustainability Assessment, Department of Management Engineering (Denmark); Jolliet, Olivier [University of Michigan, Department of Environmental Health Sciences, School of Public Health (United States)

2017-04-15

As engineered nanomaterials are increasingly introduced on the market into a broad range of commodities or nanoproducts, there is a need for operational, reliable tool, enabling to consistently assess the risks and impacts associated with the releases of nanoparticles. The lack of a developed metric that accurately represents their toxic effects while capturing the influence of the most relevant physicochemical properties is one of the major impediments. Here, we investigate the relationships between the toxic responses of nano-sized and micro-sized particles in in vivo toxicological studies and their physicochemical properties. Our results for TiO{sub 2} particles indicate statistically significant associations between the primary particle size and their toxicity responses for combined inhalation and ingestion exposure routes, although the numerical values should be considered with care due to the inability to encompass influences from other relevant physicochemical properties like surface coatings. These findings allow for expressing mass-based adverse effect levels as a continuous function of the primary size of particles. This meaningful, exploratory metric can thus be used for screening purposes and pave the way for reaching adaptive, robust risk assessments of nanomaterials, e.g. for setting up consistent threshold levels, as well as consistent life cycle assessments of nanoproducts. We provide examples of such applications.

Leptin levels distribution and ethnic background in two populations from Chile: Caucasian and Mapuche groups.

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Pérez-Bravo, F; Albala, C; Santos, J L; Yañez, M; Carrasco, E

1998-10-01

Leptin, the product of the human ob gene is increased in obese individuals, suggesting resistance to its effect. We examined the relationship of serum leptin levels with respect to obesity, gender and insulin levels in two populations with different ethnic compositions in Chile. Leptin and insulin levels were determined by radioimmunoassay (RIA) and correlated with body mass index (BMI), gender and ethnic background. 79 Caucasian subjects from Santiago and 65 Mapuche natives from the Araucania region, Chile, were included in this study. Leptin concentrations in obese subjects were significantly increased in both ethnic groups in relation to lean status: Caucasian and Mapuche obese 19.3 +/- 11.6 and 10.1 +/- 5.8 (P Mapuche lean 10.4 +/- 5.8 and 4.7 +/- 2.9 (P Mapuche and Caucasian groups, similar leptin levels were observed among the males of the two populations in both metabolic states (lean and obese). In contrast, the leptin level distributions between women showed a marked difference, having a minor value in the Mapuche women with a comparable value with the male group in this ethnic population. The leptin concentrations are associated with obesity in both ethnic groups in Chile. However, the leptin levels between the Mapuche natives were significantly decreased compared to the Caucasian group. The gender distribution does not seem to be important in the Mapuche natives. The ethnic composition seems to be important in the leptin distribution in the analysed populations.

Scaling-Up Effective Language and Literacy Instruction: Evaluating the Importance of Scripting and Group Size Components

DEFF Research Database (Denmark)

Bleses, Dorthe; Højen, Anders; Dale, Philip

2018-01-01

participated in a cluster-randomized evaluation of three variations of a language-literacy focused curriculum (LEAP) comprising 40 twice-weekly 30-min lessons. LEAP-LARGE and LEAP-SMALL conditions involved educators’ implementation of a scope and sequence of objectives using scripted lessons provided to whole......-class and small groups, respectively. In LEAP-OPEN, educators followed the scope and sequence but were allowed to determine the instructional activities for each of 40 lessons (i.e., they received no scripted lessons). A business-as-usual (BAU) condition served as the control. Overall, the largest effect sizes...

How within-group behavioural variation and task efficiency enhance fitness in a social group.

Science.gov (United States)

Pruitt, Jonathan N; Riechert, Susan E

2011-04-22

How task specialization, individual task performance and within-group behavioural variation affects fitness is a longstanding and unresolved problem in our understanding of animal societies. In the temperate social spider, Anelosimus studiosus, colony members exhibit a behavioural polymorphism; females either exhibit an aggressive 'asocial' or docile 'social' phenotype. We assessed individual prey-capture success for both phenotypes, and the role of phenotypic composition on group-level prey-capture success for three prey size classes. We then estimated the effect of group phenotypic composition on fitness in a common garden, as inferred from individual egg-case masses. On average, asocial females were more successful than social females at capturing large prey, and colony-level prey-capture success was positively associated with the frequency of the asocial phenotype. Asocial colony members were also more likely to engage in prey-capture behaviour in group-foraging situations. Interestingly, our fitness estimates indicate females of both phenotypes experience increased fitness when occupying colonies containing unlike individuals. These results imply a reciprocal fitness benefit of within-colony behavioural variation, and perhaps division of labour in a spider society.

Temporary core liquid level depression during cold-leg small-break LOCA effect of break size and power level

International Nuclear Information System (INIS)

Koizumi, Y.; Kumamaru, H.; Mimura, Y.; Kukita, Y.; Tasaka, K.

1989-01-01

Cold-leg small break LOCA experiments (0.5-10% break) were conducted at the large scale test facility (LSTF), a volumetrically-scaled (1/48) simulator of a PWR, of the ROSA-IV Program. When a break area was less than 2.5% of the scaled cold-leg flow area, the core liquid level was temporarily further depressed to the bottom elevation of the crossover leg during the loop seal clearing early in the transient only by the manometric pressure balance since no coolant remained in the upper portion of the primary system. When the break size was larger than 5%, the core liquid level was temporarily further depressed lower than the bottom elevation of the crossover leg during the loop seal clearing since coolant remained at the upper portion of the primary system; the steam generator (SG) U-tube upflow side and the SG inlet plenum, due to counter current flow limiting by updrafting steam while the coolant drained. The amount of coolant trapped there was dependent on the vapor velocity (core power); the larger the core power, the lower the minimum core liquid level. The RELAP5/MOD2 code reasonable predicted phenomena observed in the experiments. (orig./DG)

[The effect of group-based psychodrama therapy on decreasing the level of aggression in adolescents].

Science.gov (United States)

Karataş, Zeynep; Gökçakan, Dan Zafer

2009-01-01

This study aimed to examine the effect of group-based psychodrama therapy on the level aggression in adolescents. The study included 23 students from Nezihe Yalvac Anatolian Vocational High School of Hotel Management and Tourism that had high aggression scores. Eleven of the participants (6 female, 5 male) constituted the experimental group and 12 (6 male, 6 female) were in the control group. The 34-item Aggression Scale was used to measure level of aggression. We utilized mixed pattern design including experiment-control, pre-test and post test and follow up. The experimental group participated in group-based psychodrama therapy once a week for 90 minutes, for 14 weeks in total. The Aggression Scale was administered to the experimental and control groups before and after treatment; it was additionally administered to the experimental group 16 weeks after treatment. Data were analyzed using ANCOVA and dependent samples t tests. Our analysis shows that group-based psychodrama had an effect on the experimental group in terms of total aggression, anger, hostility, and indirect aggression scores (F=65.109, F=20.175, F=18.593, F=40.987, respectively, Ppsychodrama therapy decreased the level of aggression in the experimental group. Current findings are discussed with reference to the literature. Recommendations for further research and for psychiatric counselors are provided.

Measuring total health inequality: adding individual variation to group-level differences

Directory of Open Access Journals (Sweden)

Gakidou Emmanuela

2002-08-01

Full Text Available Abstract Background Studies have revealed large variations in average health status across social, economic, and other groups. No study exists on the distribution of the risk of ill-health across individuals, either within groups or across all people in a society, and as such a crucial piece of total health inequality has been overlooked. Some of the reason for this neglect has been that the risk of death, which forms the basis for most measures, is impossible to observe directly and difficult to estimate. Methods We develop a measure of total health inequality – encompassing all inequalities among people in a society, including variation between and within groups – by adapting a beta-binomial regression model. We apply it to children under age two in 50 low- and middle-income countries. Our method has been adopted by the World Health Organization and is being implemented in surveys around the world; preliminary estimates have appeared in the World Health Report (2000. Results Countries with similar average child mortality differ considerably in total health inequality. Liberia and Mozambique have the largest inequalities in child survival, while Colombia, the Philippines and Kazakhstan have the lowest levels among the countries measured. Conclusions Total health inequality estimates should be routinely reported alongside average levels of health in populations and groups, as they reveal important policy-related information not otherwise knowable. This approach enables meaningful comparisons of inequality across countries and future analyses of the determinants of inequality.

Group cohesion in sports teams of different professional level

OpenAIRE

Vazha M. Devishvili; Marina O. Mdivani; Daria S. Elgina

2017-01-01

Background. Team sports are not only the most exciting sporting events. but also complex activities that make serious demands on players. The effectiveness of the team depends not only on the high level of gaming interaction. but also on the relationship between the players. The work is based on the material of sports teams and is devoted to the study of the phenomenon of group cohesion. As a basic model. the authors choose a 4-factor model that describes cohesion in sports teams. The pape...

Effects of Community-Based Collaborative Group Characteristics on Social Capital

Science.gov (United States)

Wagner, Cheryl L.; Fernandez-Gimenez, Maria E.

2009-10-01

Recent research suggests that community-based collaboration may build social capital—defined as trust, norms of reciprocity, and networks. Social capital may improve a group’s ability to collaborate, manage risk, innovate, and adapt to change. We used mail surveys of group participants and key informant interviews to assess whether the following collaborative group characteristics affected social capital built within 10 collaborative groups in northwest Colorado: perceived success, conflict, activeness, stakeholder diversity, previous collaboration experience, similar values and beliefs, group size, group age, and initial social capital. Perceived success and initial levels of social capital were the strongest predictors of current levels of and changes in social capital over time. Collaboration experience negatively influenced current levels of trust. Our results suggest that collaborative groups may need to consider the outcomes of collaborative interactions in order to build social capital.

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

Science.gov (United States)

Burger, Joanna; Gochfeld, Michael

2014-01-01

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

Interaction between carbon fibers and polymer sizing: Influence of fiber surface chemistry and sizing reactivity

Science.gov (United States)

Moosburger-Will, Judith; Bauer, Matthias; Laukmanis, Eva; Horny, Robert; Wetjen, Denise; Manske, Tamara; Schmidt-Stein, Felix; Töpker, Jochen; Horn, Siegfried

2018-05-01

Different aspects of the interaction of carbon fibers and epoxy-based polymer sizings are investigated, e.g. the wetting behavior, the strength of adhesion between fiber and sizing, and the thermal stability of the sizing layer. The influence of carbon fiber surface chemistry and sizing reactivity is investigated using fibers of different degree of anodic oxidation and sizings with different number of reactive epoxy groups per molecule. Wetting of the carbon fibers by the sizing dispersion is found to be specified by both, the degree of fiber activation and the sizing reactivity. In contrast, adhesion strength between fibers and sizing is dominated by the surface chemistry of the carbon fibers. Here, the number of surface oxygen groups seems to be the limiting factor. We also find that the sizing and the additional functionalities induced by anodic oxidation are removed by thermal treatment at 600 °C, leaving the carbon fiber in its original state after carbonization.

The relationship between personality traits and anxiety/depression levels in different drug abusers' groups

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Tatalović Vorkapić Sanja

2013-12-01

Full Text Available AIM: Since psychosocial characteristics of drug abuse involve mainly specific personality and emotional changes, it is very important to investigate characteristics of addictive personality in relationship with emotional state of the individual. Considering that, the objective of this study was to analyse the relationship between personality structure and emotional state of two different groups: heroin addicts and recreate drug abusers. METHODS: The total of 288 (219 males and 69 females; 191 heroin addicts and 97 recreate drug users clients of Centre for the prevention and treatment of drug abuse in Rijeka completed Eysenck's Personality Questionnaire (EPQ R/A, Beck's Anxiety Inventory (BAI and Beck's Depression Inventory (BDI. Their average age was 22. RESULTS: In the group of heroin addicts, higher levels of anxiety and depression were significantly correlated with higher levels of psychoticism, neuroticism, criminality and addiction. In the group of recreate drug users, higher extraversion and social conformity were determined. Furthermore, in the first group was found even higher depression. However when the anxiety level was compared between these two groups, there was no significant difference. CONCLUSION: Overall, the findings implied that the used measurement instruments could serve as the useful diagnostic tools that could ensure advantageous treatment directions.

The Effect of Wheel Size on Mobility Performance in Wheelchair Athletes

NARCIS (Netherlands)

Mason, B.; van der Woude, L.; Lenton, J. P.; Goosey-Tolfrey, V.

2012-01-01

The purpose of the current study was to investigate the effects of different wheel sizes, with fixed gear ratios, on maximal effort mobility performance in wheelchair athletes. 13 highly trained wheelchair basketball players, grouped by classification level, performed a battery of 3 field tests in

Erythrocyte enzymes in groups of Rattus norvegicus with genetic differences in 2,3-diphosphoglycerate levels.

Science.gov (United States)

Noble, N A; Tanaka, K R

1979-01-01

1. A major locus with two alleles is responsible for large differences in erythrocyte 2,3-diphosphoglycerate (DPG) levels in Rattus norvegicus. Blood from homozygous High-DPG, homozygous Low-DPG and heterozygous animals was used to measure blood indices and red cell enzyme activities. 2. Significant differences between groups were found in DPG levels, white blood cell counts and hemoglobin levels. 3. The results suggest that none of the red cell enzymes assayed is structurally or quantitatively different in the three groups.

Rapid changes in the size of different functional organ and muscle groups during refueling in a long-distance migrating shorebird

NARCIS (Netherlands)

Piersma, T; Gudmundsson, GA; Lilliendahl, K; Gudmundsson, Gudmundur A.

1999-01-01

The adaptive value of size changes in different organ and muscle groups was studied in red knots (Calidris canutus islandica) in relation to their migration. Birds were sampled on five occasions: at arrival in Iceland in May 1994, two times during subsequent refueling, at departure toward, and on

Particle size and radionuclide levels in some west Cumbrian soils

International Nuclear Information System (INIS)

Livens, F.R.

1988-01-01

Four west Cumbrian soils of contrasting types, together with an estuarine silt sample, were separated into different particle size fractions by a combination of sieving and settling techniques. These sub-samples were analysed by quantitative gamma-ray spectrometry for several nuclides, principally 137 Cs, 106 Ru and 241 Am, followed by chemical separation and alpha spectrometric determination of 238,239,240 Pu. A simple empirical method of correction for differing sample sizes, and hence counting geometries, was developed for gamma spectrometry and found to give good results. The radionuclides were concentrated into the finer size fractions, with clay-sized ( 137 Cs from 3 to 35 times. The enhancement was greatest for all radionuclides in a sandy soil with a very low clay content (0.2% by weight) and it was found that, as the abundance of fine particles increased, so the concentration effect decreased. No evidence was found for a simple relationship between organic content and radionuclide activity, although the organic matter does have some effect. 17 refs.; 3 figs.; 6 tabs

Elementary physical education: A focus on fitness activities and smaller class sizes are associated with higher levels of physical activity

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Mandy Kirkham-King

2017-12-01

Full Text Available Optimizing physical activity during physical education is necessary for children to achieve daily physical activity recommendations. The purpose of this study was to examine the relationship among various contextual factors with accelerometer measured physical activity during elementary physical education. Data were collected during 2015–2016 from 281 students (1st–5th grade, 137 males, 144 females from a private school located in a metropolitan area of Utah in the U.S. Students wore accelerometers for 12 consecutive weeks at an accelerometer wear frequency of 3days per week during physical education. A multi-level general linear mixed effects model was employed to examine the relationship among various physical education contextual factors and percent of wear time in moderate-to-vigorous physical activity (%MVPA, accounting for clustering of observations within students and the clustering of students within classrooms. Explored contextual factors included grade level, lesson context, sex, and class size. Main effects and interactions among the factors were explored in the multi-level models. A two-way interaction of lesson context and class size on %MVPA was shown to be statistically significant. The greatest differences were found to be between fitness lessons using small class sizes compared to motor skill lessons using larger class sizes (β=14.8%, 95% C.I. 5.7%–23.9% p<0.001. Lessons that included a focus on fitness activities with class sizes that were <25 students associated with significantly higher %MVPA during elementary physical education. Keywords: Exercise, Physical education and training, Adolescents

Body size distribution of the dinosaurs.

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Eoin J O'Gorman

Full Text Available The distribution of species body size is critically important for determining resource use within a group or clade. It is widely known that non-avian dinosaurs were the largest creatures to roam the Earth. There is, however, little understanding of how maximum species body size was distributed among the dinosaurs. Do they share a similar distribution to modern day vertebrate groups in spite of their large size, or did they exhibit fundamentally different distributions due to unique evolutionary pressures and adaptations? Here, we address this question by comparing the distribution of maximum species body size for dinosaurs to an extensive set of extant and extinct vertebrate groups. We also examine the body size distribution of dinosaurs by various sub-groups, time periods and formations. We find that dinosaurs exhibit a strong skew towards larger species, in direct contrast to modern day vertebrates. This pattern is not solely an artefact of bias in the fossil record, as demonstrated by contrasting distributions in two major extinct groups and supports the hypothesis that dinosaurs exhibited a fundamentally different life history strategy to other terrestrial vertebrates. A disparity in the size distribution of the herbivorous Ornithischia and Sauropodomorpha and the largely carnivorous Theropoda suggests that this pattern may have been a product of a divergence in evolutionary strategies: herbivorous dinosaurs rapidly evolved large size to escape predation by carnivores and maximise digestive efficiency; carnivores had sufficient resources among juvenile dinosaurs and non-dinosaurian prey to achieve optimal success at smaller body size.

Body size distribution of the dinosaurs.

Science.gov (United States)

O'Gorman, Eoin J; Hone, David W E

2012-01-01

The distribution of species body size is critically important for determining resource use within a group or clade. It is widely known that non-avian dinosaurs were the largest creatures to roam the Earth. There is, however, little understanding of how maximum species body size was distributed among the dinosaurs. Do they share a similar distribution to modern day vertebrate groups in spite of their large size, or did they exhibit fundamentally different distributions due to unique evolutionary pressures and adaptations? Here, we address this question by comparing the distribution of maximum species body size for dinosaurs to an extensive set of extant and extinct vertebrate groups. We also examine the body size distribution of dinosaurs by various sub-groups, time periods and formations. We find that dinosaurs exhibit a strong skew towards larger species, in direct contrast to modern day vertebrates. This pattern is not solely an artefact of bias in the fossil record, as demonstrated by contrasting distributions in two major extinct groups and supports the hypothesis that dinosaurs exhibited a fundamentally different life history strategy to other terrestrial vertebrates. A disparity in the size distribution of the herbivorous Ornithischia and Sauropodomorpha and the largely carnivorous Theropoda suggests that this pattern may have been a product of a divergence in evolutionary strategies: herbivorous dinosaurs rapidly evolved large size to escape predation by carnivores and maximise digestive efficiency; carnivores had sufficient resources among juvenile dinosaurs and non-dinosaurian prey to achieve optimal success at smaller body size.

Body Size Distribution of the Dinosaurs

Science.gov (United States)

O’Gorman, Eoin J.; Hone, David W. E.

2012-01-01

The distribution of species body size is critically important for determining resource use within a group or clade. It is widely known that non-avian dinosaurs were the largest creatures to roam the Earth. There is, however, little understanding of how maximum species body size was distributed among the dinosaurs. Do they share a similar distribution to modern day vertebrate groups in spite of their large size, or did they exhibit fundamentally different distributions due to unique evolutionary pressures and adaptations? Here, we address this question by comparing the distribution of maximum species body size for dinosaurs to an extensive set of extant and extinct vertebrate groups. We also examine the body size distribution of dinosaurs by various sub-groups, time periods and formations. We find that dinosaurs exhibit a strong skew towards larger species, in direct contrast to modern day vertebrates. This pattern is not solely an artefact of bias in the fossil record, as demonstrated by contrasting distributions in two major extinct groups and supports the hypothesis that dinosaurs exhibited a fundamentally different life history strategy to other terrestrial vertebrates. A disparity in the size distribution of the herbivorous Ornithischia and Sauropodomorpha and the largely carnivorous Theropoda suggests that this pattern may have been a product of a divergence in evolutionary strategies: herbivorous dinosaurs rapidly evolved large size to escape predation by carnivores and maximise digestive efficiency; carnivores had sufficient resources among juvenile dinosaurs and non-dinosaurian prey to achieve optimal success at smaller body size. PMID:23284818

[Influences of ration level and initial body weight on growth and size hierarchy of hybrid tilapia, Oreochromis mossambicus x O. niloticus].

Science.gov (United States)

Wang, Yan

2003-02-01

72 hybrid tilapia were distributed into twelve tanks, each stocked in six fish (A, B, C, D, E, F) with different body size. The initial body weight was 62.69 +/- 1.46 g for fish A, 56.48 +/- 1.30 g for B, 50.75 +/- 1.19 g for C, 35.56 +/- 1.18 g for D, 31.05 +/- 0.88 g for E, and 27.35 +/- 0.95 g for F (mean +/- SE). The fish were reared under four ration levels (deprived of feed, fed at 1.5% body weight per day (BW.d-1), fed at 3.0% BW.d-1, or fed excess) throughout four weeks, respectively. The specific growth rate (SGR) and feed efficiency (FE) of the fish increased with increasing ration level up to 3.0% BW.d-1, and then, SGR maintained at a constant level while FE dropped with continuing increase of ration. The variance coefficient of SGR and final body weight was relatively high in the fish that fed at 1.5% BW.d-1. For fish A, SGR was not significantly different, between 1.5% BW.d-1, 3.0% BW.d-1 and fed excess, while in fish F, relatively high variations were found among different ration treatments. This experiment revealed that the growth and size hierarchy of hybrid tilapia were related to their ration level and initial body size. Under ration levels more than 3.0% BW.d-1, SGR was usually high, and size hierarchy was relatively weak.

Ultrasound measurement of the size of the anterior tibial muscle group: the effect of exercise and leg dominance

LENUS (Irish Health Repository)

McCreesh, Karen

2011-09-13

Abstract Background Knowledge of normal muscle characteristics is crucial in planning rehabilitation programmes for injured athletes. There is a high incidence of ankle and anterior tibial symptoms in football players, however little is known about the effect of limb dominance on the anterior tibial muscle group (ATMG). The purpose of this study was to assess the effect of limb dominance and sports-specific activity on ATMG thickness in Gaelic footballers and non-football playing controls using ultrasound measurements, and to compare results from transverse and longitudinal scans. Methods Bilateral ultrasound scans were taken to assess the ATMG size in 10 Gaelic footballers and 10 sedentary controls (age range 18-25 yrs), using a previously published protocol. Both transverse and longitudinal images were taken. Muscle thickness measurements were carried out blind to group and side of dominance, using the Image-J programme. Results Muscle thickness on the dominant leg was significantly greater than the non-dominant leg in the footballers with a mean difference of 7.3%, while there was no significant dominance effect in the controls (p < 0.05). There was no significant difference between the measurements from transverse or longitudinal scans. Conclusions A significant dominance effect exists in ATMG size in this group of Gaelic footballers, likely attributable to the kicking action involved in the sport. This should be taken into account when rehabilitating footballers with anterior tibial pathology. Ultrasound is a reliable tool to measure ATMG thickness, and measurement may be taken in transverse or longitudinal section.

Simultaneous measurements of particle number size distributions at ground level and 260 m on a meteorological tower in urban Beijing, China

Science.gov (United States)

Du, Wei; Zhao, Jian; Wang, Yuying; Zhang, Yingjie; Wang, Qingqing; Xu, Weiqi; Chen, Chen; Han, Tingting; Zhang, Fang; Li, Zhanqing; Fu, Pingqing; Li, Jie; Wang, Zifa; Sun, Yele

2017-06-01

Despite extensive studies into the characterization of particle number size distributions at ground level, real-time measurements above the urban canopy in the megacity of Beijing have never been performed to date. Here we conducted the first simultaneous measurements of size-resolved particle number concentrations at ground level and 260 m in urban Beijing from 22 August to 30 September. Our results showed overall similar temporal variations in number size distributions between ground level and 260 m, yet periods with significant differences were also observed. Particularly, accumulation-mode particles were highly correlated (r2 = 0. 85) at the two heights, while Aitken-mode particles presented more differences. Detailed analysis suggests that the vertical differences in number concentrations strongly depended on particle size, and particles with a mobility diameter between 100 and 200 nm generally showed higher concentrations at higher altitudes. Particle growth rates and condensation sinks were also calculated, which were 3.2 and 3.6 nm h-1, and 2.8 × 10-2 and 2.9 × 10-2 s-1, at ground level and 260 m, respectively. By linking particle growth with aerosol composition, we found that organics appeared to play an important role in the early stage of the growth (09:00-12:00 LT) while sulfate was also important during the later period. Positive matrix factorization of size-resolved number concentrations identified three common sources at ground level and 260 m, including a factor associated with new particle formation and growth events (NPEs), and two secondary factors that represent photochemical processing and regional transport. Cooking emission was found to have a large contribution to small particles and showed much higher concentration at ground level than 260 m in the evening. These results imply that investigation of NPEs at ground level in megacities needs to consider the influences of local cooking emissions. The impacts of regional emission controls on

The Influence of Study-Level Inference Models and Study Set Size on Coordinate-Based fMRI Meta-Analyses

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Han Bossier

2018-01-01

Full Text Available Given the increasing amount of neuroimaging studies, there is a growing need to summarize published results. Coordinate-based meta-analyses use the locations of statistically significant local maxima with possibly the associated effect sizes to aggregate studies. In this paper, we investigate the influence of key characteristics of a coordinate-based meta-analysis on (1 the balance between false and true positives and (2 the activation reliability of the outcome from a coordinate-based meta-analysis. More particularly, we consider the influence of the chosen group level model at the study level [fixed effects, ordinary least squares (OLS, or mixed effects models], the type of coordinate-based meta-analysis [Activation Likelihood Estimation (ALE that only uses peak locations, fixed effects, and random effects meta-analysis that take into account both peak location and height] and the amount of studies included in the analysis (from 10 to 35. To do this, we apply a resampling scheme on a large dataset (N = 1,400 to create a test condition and compare this with an independent evaluation condition. The test condition corresponds to subsampling participants into studies and combine these using meta-analyses. The evaluation condition corresponds to a high-powered group analysis. We observe the best performance when using mixed effects models in individual studies combined with a random effects meta-analysis. Moreover the performance increases with the number of studies included in the meta-analysis. When peak height is not taken into consideration, we show that the popular ALE procedure is a good alternative in terms of the balance between type I and II errors. However, it requires more studies compared to other procedures in terms of activation reliability. Finally, we discuss the differences, interpretations, and limitations of our results.

Galectin-3 levels relate in children to total body fat, abdominal fat, body fat distribution, and cardiac size.

Science.gov (United States)

Dencker, Magnus; Arvidsson, Daniel; Karlsson, Magnus K; Wollmer, Per; Andersen, Lars B; Thorsson, Ola

2018-03-01

Galectin-3 has recently been proposed as a novel biomarker for cardiovascular disease in adults. The purpose of this investigation was to assess relationships between galectin-3 levels and total body fat, abdominal fat, body fat distribution, aerobic fitness, blood pressure, left ventricular mass, left atrial size, and increase in body fat over a 2-year period in a population-based sample of children. Our study included 170 children aged 8-11 years. Total fat mass and abdominal fat were measured by dual-energy x-ray absorptiometry (DXA). Body fat distribution was expressed as abdominal fat/total fat mass. Maximal oxygen uptake was assessed by indirect calorimetry during a maximal exercise test and scaled to body mass. Systolic and diastolic blood pressure and pulse pressure were measured. Left atrial size, left ventricular mass, and relative wall thickness were measured by echocardiography. Frozen serum samples were analyzed for galectin-3 by the Proximity Extension Assay technique. A follow-up DXA scan was performed in 152 children 2 years after the baseline exam. Partial correlations, with adjustment for sex and age, between galectin-3 versus body fat measurements indicated weak to moderate relationships. Moreover, left atrial size, left ventricular mass, and relative wall thickness and pulse pressure were also correlated with galectin-3. Neither systolic blood pressure nor maximal oxygen uptake was correlated with galectin-3. There was also a correlation between galectin-3 and increase in total body fat over 2 years, while no such correlations were found for the other fat measurements. More body fat and abdominal fat, more abdominal body fat distribution, more left ventricular mass, and increased left atrial size were all associated with higher levels of galectin-3. Increase in total body fat over 2 years was also associated with higher levels of galectin-3. What is Known: • Galectin-3 has been linked to obesity and been proposed to be a novel biomarker

Occupational Safety and Health Conditions Aboard Small- and Medium-Size Fishing Vessels: Differences among Age Groups.

Science.gov (United States)

Zytoon, Mohamed A; Basahel, Abdulrahman M

2017-02-24

Although marine fishing is one of the most hazardous occupations, research on the occupational safety and health (OSH) conditions aboard marine fishing vessels is scarce. For instance, little is known about the working conditions of vulnerable groups such as young and aging fishermen. The objective of the current paper is to study the OSH conditions of young and aging fishermen compared to middle-aged fishermen in the small- and medium-size (SM) marine fishing sector. A cross-sectional study was designed, and 686 fishermen working aboard SM fishing vessels were interviewed to collect information about their safety and health. The associations of physical and psychosocial work conditions with safety and health outcomes, e.g., injuries, illnesses and job satisfaction, are presented. The results of the current study can be utilized in the design of effective accident prevention and OSH training programs for the three age groups and in the regulation of working conditions aboard fishing vessels.

Widespread recent increases in county-level heart disease mortality across age groups.

Science.gov (United States)

Vaughan, Adam S; Ritchey, Matthew D; Hannan, Judy; Kramer, Michael R; Casper, Michele

2017-12-01

Recent national trends show decelerating declines in heart disease mortality, especially among younger adults. National trends may mask variation by geography and age. We examined recent county-level trends in heart disease mortality by age group. Using a Bayesian statistical model and National Vital Statistics Systems data, we estimated overall rates and percent change in heart disease mortality from 2010 through 2015 for four age groups (35-44, 45-54, 55-64, and 65-74 years) in 3098 US counties. Nationally, heart disease mortality declined in every age group except ages 55-64 years. County-level trends by age group showed geographically widespread increases, with 52.3%, 58.5%, 69.1%, and 42.0% of counties experiencing increases with median percent changes of 0.6%, 2.2%, 4.6%, and -1.5% for ages 35-44, 45-54, 55-64, and 65-74 years, respectively. Increases were more likely in counties with initially high heart disease mortality and outside large metropolitan areas. Recent national trends have masked local increases in heart disease mortality. These increases, especially among adults younger than age 65 years, represent challenges to communities across the country. Reversing these trends may require intensification of primary and secondary prevention-focusing policies, strategies, and interventions on younger populations, especially those living in less urban counties. Published by Elsevier Inc.

Accounting for imperfect detection of groups and individuals when estimating abundance.

Science.gov (United States)

Clement, Matthew J; Converse, Sarah J; Royle, J Andrew

2017-09-01

If animals are independently detected during surveys, many methods exist for estimating animal abundance despite detection probabilities account for imperfect detection of groups, while assuming that individuals within groups are detected perfectly. However, this assumption is often unsupported. We introduce an abundance estimator for grouped animals when detection of groups is imperfect and group size may be under-counted, but not over-counted. The estimator combines an MRDS model with an N-mixture model to account for imperfect detection of individuals. The new MRDS-Nmix model requires the same data as an MRDS model (independent detection histories, an estimate of distance to transect, and an estimate of group size), plus a second estimate of group size provided by the second observer. We extend the model to situations in which detection of individuals within groups declines with distance. We simulated 12 data sets and used Bayesian methods to compare the performance of the new MRDS-Nmix model to an MRDS model. Abundance estimates generated by the MRDS-Nmix model exhibited minimal bias and nominal coverage levels. In contrast, MRDS abundance estimates were biased low and exhibited poor coverage. Many species of conservation interest reside in groups and could benefit from an estimator that better accounts for imperfect detection. Furthermore, the ability to relax the assumption of perfect detection of individuals within detected groups may allow surveyors to re-allocate resources toward detection of new groups instead of extensive surveys of known groups. We believe the proposed estimator is feasible because the only additional field data required are a second estimate of group size.

Group navigation and the "many-wrongs principle" in models of animal movement.

Science.gov (United States)

Codling, E A; Pitchford, J W; Simpson, S D

2007-07-01

Traditional studies of animal navigation over both long and short distances have usually considered the orientation ability of the individual only, without reference to the implications of group membership. However, recent work has suggested that being in a group can significantly improve the ability of an individual to align toward and reach a target direction or point, even when all group members have limited navigational ability and there are no leaders. This effect is known as the "many-wrongs principle" since the large number of individual navigational errors across the group are suppressed by interactions and group cohesion. In this paper, we simulate the many-wrongs principle using a simple individual-based model of movement based on a biased random walk that includes group interactions. We study the ability of the group as a whole to reach a target given different levels of individual navigation error, group size, interaction radius, and environmental turbulence. In scenarios with low levels of environmental turbulence, simulation results demonstrate a navigational benefit from group membership, particularly for small group sizes. In contrast, when movement takes place in a highly turbulent environment, simulation results suggest that the best strategy is to navigate as individuals rather than as a group.

Cell size, genome size and the dominance of Angiosperms

Science.gov (United States)

Simonin, K. A.; Roddy, A. B.

2016-12-01

Angiosperms are capable of maintaining the highest rates of photosynthetic gas exchange of all land plants. High rates of photosynthesis depends mechanistically both on efficiently transporting water to the sites of evaporation in the leaf and on regulating the loss of that water to the atmosphere as CO2 diffuses into the leaf. Angiosperm leaves are unique in their ability to sustain high fluxes of liquid and vapor phase water transport due to high vein densities and numerous, small stomata. Despite the ubiquity of studies characterizing the anatomical and physiological adaptations that enable angiosperms to maintain high rates of photosynthesis, the underlying mechanism explaining why they have been able to develop such high leaf vein densities, and such small and abundant stomata, is still incomplete. Here we ask whether the scaling of genome size and cell size places a fundamental constraint on the photosynthetic metabolism of land plants, and whether genome downsizing among the angiosperms directly contributed to their greater potential and realized primary productivity relative to the other major groups of terrestrial plants. Using previously published data we show that a single relationship can predict guard cell size from genome size across the major groups of terrestrial land plants (e.g. angiosperms, conifers, cycads and ferns). Similarly, a strong positive correlation exists between genome size and both stomatal density and vein density that together ultimately constrains maximum potential (gs, max) and operational stomatal conductance (gs, op). Further the difference in the slopes describing the covariation between genome size and both gs, max and gs, op suggests that genome downsizing brings gs, op closer to gs, max. Taken together the data presented here suggests that the smaller genomes of angiosperms allow their final cell sizes to vary more widely and respond more directly to environmental conditions and in doing so bring operational photosynthetic

Determinants of Awareness, Consideration, and Choice Set Size in University Choice.

Science.gov (United States)

Dawes, Philip L.; Brown, Jennifer

2002-01-01

Developed and tested a model of students' university "brand" choice using five individual-level variables (ethnic group, age, gender, number of parents going to university, and academic ability) and one situational variable (duration of search) to explain variation in the sizes of awareness, consideration, and choice decision sets. (EV)

Skeletal muscle glycogen content and particle size of distinct subcellular localizations in the recovery period after a high-level soccer match

DEFF Research Database (Denmark)

Nielsen, Joachim; Krustrup, Peter; Nybo, Lars

2012-01-01

Whole muscle glycogen levels remain low for a prolonged period following a soccer match. The present study was conducted to investigate how this relates to glycogen content and particle size in distinct subcellular localizations. Seven high-level male soccer players had a vastus lateralis muscle...... biopsy collected immediately after and 24, 48, 72 and 120 h after a competitive soccer match. Transmission electron microscopy was used to estimate the subcellular distribution of glycogen and individual particle size. During the first day of recovery, glycogen content increased by ~60% in all...

Effect of radiation dose level on accuracy and precision of manual size measurements in chest tomosynthesis evaluated using simulated pulmonary nodules

International Nuclear Information System (INIS)

Soederman, Christina; Allansdotter Johnsson, Aase; Vikgren, Jenny; Rossi Norrlund, Rauni; Molnar, David; Svalkvist, Angelica; Maansson, Lars Gunnar; Baath, Magnus

2016-01-01

The aim of the present study was to investigate the dependency of the accuracy and precision of nodule diameter measurements on the radiation dose level in chest tomosynthesis. Artificial ellipsoid-shaped nodules with known dimensions were inserted in clinical chest tomosynthesis images. Noise was added to the images in order to simulate radiation dose levels corresponding to effective doses for a standard-sized patient of 0.06 and 0.04 mSv. These levels were compared with the original dose level, corresponding to an effective dose of 0.12 mSv for a standard-sized patient. Four thoracic radiologists measured the longest diameter of the nodules. The study was restricted to nodules located in high-dose areas of the tomosynthesis projection radiographs. A significant decrease of the measurement accuracy and intra-observer variability was seen for the lowest dose level for a subset of the observers. No significant effect of dose level on the interobserver variability was found. The number of non-measurable small nodules (≤5 mm) was higher for the two lowest dose levels compared with the original dose level. In conclusion, for pulmonary nodules at positions in the lung corresponding to locations in high-dose areas of the projection radiographs, using a radiation dose level resulting in an effective dose of 0.06 mSv to a standard-sized patient may be possible in chest tomosynthesis without affecting the accuracy and precision of nodule diameter measurements to any large extent. However, an increasing number of non-measurable small nodules (≤5 mm) with decreasing radiation dose may raise some concerns regarding an applied general dose reduction for chest tomosynthesis examinations in the clinical praxis. (authors)

How Group Size and Composition Influences the Effectiveness of Collaborative Screen-Based Simulation Training: A Study of Dental and Nursing University Students Learning Radiographic Techniques

Directory of Open Access Journals (Sweden)

Tor Söderström

2012-12-01

Full Text Available This study analyses how changes in the design of screen-based computer simulation training influence the collaborative training process. Specifically, this study examine how the size of a group and a group’s composition influence the way these tools are used. One case study consisted of 18+18 dental students randomized into either collaborative 3D simulation training or conventional collaborative training. The students worked in groups of three. The other case consisted of 12 nursing students working in pairs (partners determined by the students with a 3D simulator. The results showed that simulation training encouraged different types of dialogue compared to conventional training and that the communication patterns were enhanced in the nursing students ́ dyadic simulation training. The concrete changes concerning group size and the composition of the group influenced the nursing students’ engagement with the learning environment and consequently the communication patterns that emerged. These findings suggest that smaller groups will probably be more efficient than larger groups in a free collaboration setting that uses screen-based simulation training.

Body size diversity and frequency distributions of Neotropical cichlid fishes (Cichliformes: Cichlidae: Cichlinae.

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Sarah E Steele

Full Text Available Body size is an important correlate of life history, ecology and distribution of species. Despite this, very little is known about body size evolution in fishes, particularly freshwater fishes of the Neotropics where species and body size diversity are relatively high. Phylogenetic history and body size data were used to explore body size frequency distributions in Neotropical cichlids, a broadly distributed and ecologically diverse group of fishes that is highly representative of body size diversity in Neotropical freshwater fishes. We test for divergence, phylogenetic autocorrelation and among-clade partitioning of body size space. Neotropical cichlids show low phylogenetic autocorrelation and divergence within and among taxonomic levels. Three distinct regions of body size space were identified from body size frequency distributions at various taxonomic levels corresponding to subclades of the most diverse tribe, Geophagini. These regions suggest that lineages may be evolving towards particular size optima that may be tied to specific ecological roles. The diversification of Geophagini appears to constrain the evolution of body size among other Neotropical cichlid lineages; non-Geophagini clades show lower species-richness in body size regions shared with Geophagini. Neotropical cichlid genera show less divergence and extreme body size than expected within and among tribes. Body size divergence among species may instead be present or linked to ecology at the community assembly scale.

Digging deeper into platform game level design: session size and sequential features

DEFF Research Database (Denmark)

Shaker, Noor; Yannakakis, Georgios N.; Togelius, Julian

2012-01-01

A recent trend within computational intelligence and games research is to investigate how to affect video game players’ in-game experience by designing and/or modifying aspects of game content. Analysing the relationship between game content, player behaviour and self-reported affective states...... constitutes an important step towards understanding game experience and constructing effective game adaptation mechanisms. This papers reports on further refinement of a method to understand this relationship by analysing data collected from players, building models that predict player experience...... and analysing what features of game and player data predict player affect best. We analyse data from players playing 780 pairs of short game sessions of the platform game Super Mario Bros, investigate the impact of the session size and what part of the level that has the major affect on player experience...

Photoluminescence effects of graphitic core size and surface functional groups in carbon dots: COO− induced red-shift emission

KAUST Repository

Hola, Katerina; Bourlinos, Athanasios B.; Kozak, Ondrej; Berka, Karel; Siskova, Karolina M.; Havrdova, Marketa; Tucek, Jiri; Safarova, Klara; Otyepka, Michal; Giannelis, Emmanuel P.; Zboril, Radek

2014-01-01

We present a simple molecular approach to control the lipophilic/ hydrophilic nature of photoluminescent carbon dots (CDs) based on pyrolysis of alkyl gallate precursors. Depending on the gallic acid derivative used, CDs with different alkyl groups (methyl, propyl, lauryl) on the surface can be obtained by isothermal heating at 270 C. This precursor-derived approach allows not only the control of lipophilicity but also the length of the particular alkyl chain enables the control over both the size and photoluminescence (PL) of the prepared CDs. Moreover, the alkyl chains on the CDs surface can be readily converted to carboxylate groups via a mild base hydrolysis to obtain water dispersible CDs with a record biocompatibility. The observed differences in PL properties of CDs and time-resolved PL data, including contributions from carbogenic cores and surface functional group, are rationalized and discussed in detail using time-dependent density functional theory (TD-DFT) calculations. © 2013 Elsevier Ltd. All rights reserved.

Photoluminescence effects of graphitic core size and surface functional groups in carbon dots: COO− induced red-shift emission

KAUST Repository

Hola, Katerina

2014-04-01

We present a simple molecular approach to control the lipophilic/ hydrophilic nature of photoluminescent carbon dots (CDs) based on pyrolysis of alkyl gallate precursors. Depending on the gallic acid derivative used, CDs with different alkyl groups (methyl, propyl, lauryl) on the surface can be obtained by isothermal heating at 270 C. This precursor-derived approach allows not only the control of lipophilicity but also the length of the particular alkyl chain enables the control over both the size and photoluminescence (PL) of the prepared CDs. Moreover, the alkyl chains on the CDs surface can be readily converted to carboxylate groups via a mild base hydrolysis to obtain water dispersible CDs with a record biocompatibility. The observed differences in PL properties of CDs and time-resolved PL data, including contributions from carbogenic cores and surface functional group, are rationalized and discussed in detail using time-dependent density functional theory (TD-DFT) calculations. © 2013 Elsevier Ltd. All rights reserved.

Corporate level strategic analysis and choice as a measure of achieving performance in organizations: (a survey of Dangote groups of companies/conglomerates quoted on Nigeria stock exchange market

Directory of Open Access Journals (Sweden)

Sev Joseph Teryima

2014-07-01

Full Text Available The objective of the research is to establish the factors that are responsible to organizational growth level in Dangote group of companies. These factors ranges from market share growth, sales volume growth (turnover, profitability, competitive advantage and share capital size amongst others. Corporate level strategic analysis and choice was adopted with specific emphasis on Boston Consulting Group (BCG matrix – portfolio analysis. Four (4 companies from Dangote conglomerate quoted on the Nigerian Stock Exchange market namely; Dangote Cement Plc, Dangote Flour Plc, Dangote Sugar Refinery Company Plc and National Salt Company of Nigeria Plc were surveyed with a population size of 5060. The sample size survey was 371. 209 respondents from Dangote Cement Company Plc, 75 respondents from Dangote Flour Mill Plc, 48 respondents from Dangote Sugar Refinery Company Plc and 39 respondents from National Salt Company Plc using judgmental and convenience sampling technique. The Quasi-experimental survey technique especially the cross-sectional design method was adopted. The Friedman Ranking test was carried out in testing the formulated hypothesis. The test of the result revealed that there is a relationship between organizational factors such as market share growth, sales volume growth (turnover, profitability growth, effective strategy application, competitive advantage and share capital size and organizational growth in the Dangote Cement Company Plc and Dangote Flour Mills Plc with a 0.425 and 0.360 strength of association respectively and the hypothesis was rejected while for Dangote Sugar Refinery Company Plc and National Salt Company of Nigeria Plc, that was not the case and the hypothesis was accepted that organizational factors such as market share, sales volume (turnover, profitability growth, effective strategy application, competitive advantage and share capital growth does not influence organizational growth hence their hypothesis were

Evaluation of Intelligent Grouping Based on Learners' Collaboration Competence Level in Online Collaborative Learning Environment

Science.gov (United States)

Muuro, Maina Elizaphan; Oboko, Robert; Wagacha, Waiganjo Peter

2016-01-01

In this paper we explore the impact of an intelligent grouping algorithm based on learners' collaborative competency when compared with (a) instructor based Grade Point Average (GPA) method level and (b) random method, on group outcomes and group collaboration problems in an online collaborative learning environment. An intelligent grouping…

Individual-level movement bias leads to the formation of higher-order social structure in a mobile group of baboons.

Science.gov (United States)

Bonnell, Tyler R; Clarke, Parry M; Henzi, S Peter; Barrett, Louise

2017-07-01

In mobile social groups, influence patterns driving group movement can vary between democratic and despotic. The arrival at any single pattern of influence is thought to be underpinned by both environmental factors and group composition. To identify the specific patterns of influence driving travel decision-making in a chacma baboon troop, we used spatially explicit data to extract patterns of individual movement bias. We scaled these estimates of individual-level bias to the level of the group by constructing an influence network and assessing its emergent structural properties. Our results indicate that there is heterogeneity in movement bias: individual animals respond consistently to particular group members, and higher-ranking animals are more likely to influence the movement of others. This heterogeneity resulted in a group-level network structure that consisted of a single core and two outer shells. Here, the presence of a core suggests that a set of highly interdependent animals drove routine group movements. These results suggest that heterogeneity at the individual level can lead to group-level influence structures, and that movement patterns in mobile social groups can add to the exploration of both how these structures develop (i.e. mechanistic aspects) and what consequences they have for individual- and group-level outcomes (i.e. functional aspects).

Serum homocysteine level in gestational diabetes: a prospective study

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Davari Tanha F

2009-08-01

Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Increased total plasma homocysteine (Hcy is an accepted risk factor of cardiovascular disease (CVD, stroke, preclampsia, recurrent abortion and diabetes type I and II. The aim of the current study was to assess serum homocysteine and its relation with serum folat, vitamine B12 and lipid profile in gestational diabetes mellitus and to compare these with those of pregnant women."n"n Methods: In a prospective controlled survey 80 pregnant women (24-28 weeks with uncomplicated pregnancies were evaluated. They were assigned to one of two groups according to the results of 100g-OGTT. In the case group there were pregnant women with gestational diabetes mellitus according to the OGTT and in the control group women who had normal OGTT results were put. Levels of fasting glucose, homocysteine, vit B12, and folic acid, uric acid, total cholesterol, triglyceride, Low Density Lipoprotein cholesterol (LDL and High Density Lipoprotein cholesterol (HDL were measured in both groups."n"nResults: The mean level of homocysteine in GDM group was significantly higher than control group (p=0.000. The mean level of folic acid and vit B12 was significantly lower than the level in control group (p=0.001, p=0.004 respectively. Body

Exploring a Relational Cultural Group Trainee Model for Master's Level Counseling Students

Science.gov (United States)

Hall, Brenda S.; Harper, Irene; Korcuska, James

2018-01-01

We explored students' experiences of a graduate level group course infused with components of the Relational Cultural Theory (RCT). During the didactic and experiential aspects of 2 semester-long group courses, the faculty instructors and students focused on creating an environment of safety, connection, and empowerment. The instructor and…

Female dominance in human groups : Effects of sex ratio and conflict level

NARCIS (Netherlands)

Stroebe, Katherine; Nijstad, Bernard A.; Hemelrijk, Charlotte K.

Compared to men, women less often attain high-level positions and generally have lower status in society. In smaller groups, the relative influence of men and women depends on gender composition, but research is inconclusive regarding the relation between gender composition and female influence.

Does bipedality predict the group-level manual laterality in mammals?

Science.gov (United States)

Giljov, Andrey; Karenina, Karina; Malashichev, Yegor

2012-01-01

Factors determining patterns of laterality manifestation in mammals remain unclear. In primates, the upright posture favours the expression of manual laterality across species, but may have little influence within a species. Whether the bipedalism acts the same in non-primate mammals is unknown. Our recent findings in bipedal and quadrupedal marsupials suggested that differences in laterality pattern, as well as emergence of manual specialization in evolution might depend on species-specific body posture. Here, we evaluated the hypothesis that the postural characteristics are the key variable shaping the manual laterality expression across mammalian species. We studied forelimb preferences in a most bipedal marsupial, brush-tailed bettong, Bettongia penicillata in four different types of unimanual behavior. The significant left-forelimb preference at the group level was found in all behaviours studied. In unimanual feeding on non-living food, catching live prey and nest-material collecting, all or most subjects were lateralized, and among lateralized bettongs a significant majority displayed left-forelimb bias. Only in unimanual supporting of the body in the tripedal stance the distribution of lateralized and non-lateralized individuals did not differ from chance. Individual preferences were consistent across all types of behaviour. The direction or the strength of forelimb preferences were not affected by the animals' sex. Our findings support the hypothesis that the expression of manual laterality depends on the species-typical postural habit. The interspecies comparison illustrates that in marsupials the increase of bipedality corresponds with the increase of the degree of group-level forelimb preference in a species. Thus, bipedalism can predict pronounced manual laterality at both intra- and interspecific levels in mammals. We also conclude that quadrupedal position in biped species can slightly hinder the expression of manual laterality, but the evoked biped

Size-dependent effects of low level cadmium and zinc exposure on the metabolome of the Asian clam, Corbicula fluminea

International Nuclear Information System (INIS)

Spann, Nicole; Aldridge, David C.; Griffin, Julian L.; Jones, Oliver A.H.

2011-01-01

Highlights: Small and large Corbicula fluminea were exposed to cadmium and zinc spiked sediment. Metabolomic changes in the freshwater clams were determined by NMR and GC–MS. Metabolic perturbations were related to amino acid and energy related metabolism. Small and large clams were differentiated by their metabolic composition. Size classes showed opposite responses to metal stress. - Abstract: The toxic effects of low level metal contamination in sediments are currently poorly understood. We exposed different sized Asian clams, Corbicula fluminea, to sediment spiked with environmentally relevant concentrations of either zinc, cadmium or a zinc–cadmium mixture for one week. This freshwater bivalve is well suited for sediment toxicity tests as it lives partly buried in the sediment and utilises sediment particles as a food resource. After one week, the whole tissue composition of low molecular weight metabolites was analysed by nuclear magnetic resonance spectroscopy (NMR) and gas chromatography–mass spectrometry (GC–MS). The condition index (ratio of tissue dry weight to volume inside the shell valves) was also measured. Small and large clams were clearly differentiated by their metabolic composition and the two size classes showed opposite responses to the mixture spiked sediment. No effects of zinc alone on the metabolome were found and cadmium only influenced the smaller size class. The main perturbations were seen in amino acid and energy metabolism, with small clams using amino acids as an energy resource and larger clams primarily drawing on their larger storage reserves of carbohydrates. Our study demonstrates that metabolomics is a useful technique to test for low level toxicity which does not manifest in mortality or condition index changes. The differing effects between the two size classes stress that it is important to consider age/size when conducting metabolomic and ecotoxicology assessments, since testing for the effects on only one size

Size-dependent effects of low level cadmium and zinc exposure on the metabolome of the Asian clam, Corbicula fluminea

Energy Technology Data Exchange (ETDEWEB)

Spann, Nicole, E-mail: nicole.spann@web.de [Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ (United Kingdom); Aldridge, David C., E-mail: da113@cam.ac.uk [Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ (United Kingdom); Griffin, Julian L., E-mail: jlg40@mole.bio.cam.ac.uk [Sanger Building, Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA (United Kingdom); Jones, Oliver A.H., E-mail: o.jones@gmail.com [Sanger Building, Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA (United Kingdom)

2011-10-15

Highlights: Small and large Corbicula fluminea were exposed to cadmium and zinc spiked sediment. Metabolomic changes in the freshwater clams were determined by NMR and GC-MS. Metabolic perturbations were related to amino acid and energy related metabolism. Small and large clams were differentiated by their metabolic composition. Size classes showed opposite responses to metal stress. - Abstract: The toxic effects of low level metal contamination in sediments are currently poorly understood. We exposed different sized Asian clams, Corbicula fluminea, to sediment spiked with environmentally relevant concentrations of either zinc, cadmium or a zinc-cadmium mixture for one week. This freshwater bivalve is well suited for sediment toxicity tests as it lives partly buried in the sediment and utilises sediment particles as a food resource. After one week, the whole tissue composition of low molecular weight metabolites was analysed by nuclear magnetic resonance spectroscopy (NMR) and gas chromatography-mass spectrometry (GC-MS). The condition index (ratio of tissue dry weight to volume inside the shell valves) was also measured. Small and large clams were clearly differentiated by their metabolic composition and the two size classes showed opposite responses to the mixture spiked sediment. No effects of zinc alone on the metabolome were found and cadmium only influenced the smaller size class. The main perturbations were seen in amino acid and energy metabolism, with small clams using amino acids as an energy resource and larger clams primarily drawing on their larger storage reserves of carbohydrates. Our study demonstrates that metabolomics is a useful technique to test for low level toxicity which does not manifest in mortality or condition index changes. The differing effects between the two size classes stress that it is important to consider age/size when conducting metabolomic and ecotoxicology assessments, since testing for the effects on only one size class makes

Individual and group-level job resources and their relationships with individual work engagement

OpenAIRE

F?llemann, D?sir?e; Brauchli, Rebecca; Jenny, Gregor J.; Bauer, Georg F.

2016-01-01

Objectives: This study adds a multilevel perspective to the well-researched individual-level relationship between job resources and work engagement. In addition, we explored whether individual job resources cluster within work groups because of a shared psychosocial environment and investigated whether a resource-rich psychosocial work group environment is beneficial for employee engagement over and above the beneficial effect of individual job resources and independent of their variability w...

Can foraging ecology drive the evolution of body size in a diving endotherm?

Directory of Open Access Journals (Sweden)

Timothée R Cook

Full Text Available Within a single animal species, different morphs can allow for differential exploitation of foraging niches between populations, while sexual size dimorphism can provide each sex with access to different resources. Despite being potentially important agents of evolution, resource polymorphisms, and the way they operate in wild populations, remain poorly understood. In this study, we examine how trophic factors can select for different body sizes between populations and sexes in a diving endotherm. Dive depth and duration are positively related to body size in diving birds and mammals, a relationship explained by a lower mass-specific metabolic rate and greater oxygen stores in larger individuals. Based on this allometry, we predict that selection for exploiting resources situated at different depths can drive the evolution of body size in species of diving endotherms at the population and sexual level. To test this prediction, we studied the foraging ecology of Blue-eyed Shags, a group of cormorants with male-biased sexual size dimorphism from across the Southern Ocean. We found that mean body mass and relative difference in body mass between sexes varied by up to 77% and 107% between neighbouring colonies, respectively. Birds from colonies with larger individuals dived deeper than birds from colonies with smaller individuals, when accounting for sex. In parallel, males dived further offshore and deeper than females and the sexual difference in dive depth reflected the level of sexual size dimorphism at each colony. We argue that body size in this group of birds is under intense selection for diving to depths of profitable benthic prey patches and that, locally, sexual niche divergence selection can exaggerate the sexual size dimorphism of Blue-eyed Shags initially set up by sexual selection. Our findings suggest that trophic resources can select for important geographic micro-variability in body size between populations and sexes.

Comparison of the effects of two bongo net mesh sizes on the estimation of abundance and size of Engraulidae eggs

Directory of Open Access Journals (Sweden)

Jana Menegassi del Favero

2015-06-01

Full Text Available Abstract Studies of ichthyoplankton retention by nets of different mesh sizes are important because they help in choosing a sampler when planning collection and the establishment of correction factors. These factors make it possible to compare studies performed with nets of different mesh sizes. In most studies of mesh retention of fish eggs, the taxonomic identification is done at the family level, resulting in the loss of detailed information. We separated Engraulidae eggs, obtained with 0.333 mm and 0.505 mm mesh bongo nets at 172 oceanographic stations in the southeastern Brazilian Bight, into four groups based on their morphometric characteristics. The difference in the abundance of eggs caught by the two nets was not significant for those groups with highest volume, types A and B, but in type C (Engraulis anchoita, the most eccentric, and in type D, of the smallest volume, the difference was significant. However, no significant difference was observed in the egg size sampled with each net for E. anchoita and type D, which exhibited higher abundance in the 0.333 mm mesh net and minor axis varying from 0.45-0.71 mm, smaller than the 0.505 mm mesh aperture and the mesh diagonal.

Body Size Distribution of the Dinosaurs

OpenAIRE

O?Gorman, Eoin J.; Hone, David W. E.

2012-01-01

The distribution of species body size is critically important for determining resource use within a group or clade. It is widely known that non-avian dinosaurs were the largest creatures to roam the Earth. There is, however, little understanding of how maximum species body size was distributed among the dinosaurs. Do they share a similar distribution to modern day vertebrate groups in spite of their large size, or did they exhibit fundamentally different distributions due to unique evolutiona...

The effect of presenteeism-related health conditions on employee work engagement levels: A comparison between groups

Directory of Open Access Journals (Sweden)

Leon T. de Beer

2014-10-01

Research purpose: The primary objective of this study was to determine the differences in work engagement levels based on groups of presenteeism-related conditions in employees. Motivation for the study: Awareness of the impact of presenteeism-related conditions on work engagement levels can aid in the crafting of interventions to assist employees who suffer from these conditions, which in turn can boost work engagement levels. Research design, approach and method: Cross-sectional data was collected from an availability sample of employees in the manufacturing sector (N = 3387. Main findings: The results of the multi-group structural equation modelling revealed significant mean differences in work engagement levels between the groups. Practical significance tests revealed significant differences between all the groups. The largest difference was between the group who suffered from no presenteeism-related conditions and the group who suffered from all three conditions included in this study concurrently. Practical/managerial implications: Organisational stakeholders are encouraged to take note of the effects that presenteeism-related health conditions have on work engagement and to consider relevant strategies and interventions to address and alleviate symptoms in order to tend to employee health and obviate the effect on productivity. Contribution: This study found that there were clear practical differences between employees who suffer from the presenteeism-related conditions and those who suffer from none of the conditions. Furthermore, there was also a clear difference when comparing the ‘no condition’ group to a general random sample in which employees might experience some symptoms but not comorbidity.

The number of cultural traits is correlated with female group size but not with male group size in chimpanzee communities.

Science.gov (United States)

Lind, Johan; Lindenfors, Patrik

2010-03-24

What determines the number of cultural traits present in chimpanzee (Pan troglodytes) communities is poorly understood. In humans, theoretical models suggest that the frequency of cultural traits can be predicted by population size. In chimpanzees, however, females seem to have a particularly important role as cultural carriers. Female chimpanzees use tools more frequently than males. They also spend more time with their young, skewing the infants' potential for social learning towards their mothers. In Gombe, termite fishing has been shown to be transmitted from mother to offspring. Lastly, it is female chimpanzees that transfer between communities and thus have the possibility of bringing in novel cultural traits from other communities. From these observations we predicted that females are more important cultural carriers than males. Here we show that the reported number of cultural traits in chimpanzee communities correlates with the number of females in chimpanzee communities, but not with the number of males. Hence, our results suggest that females are the carriers of chimpanzee culture.

Hierarchical modeling of cluster size in wildlife surveys

Science.gov (United States)

Royle, J. Andrew

2008-01-01

Clusters or groups of individuals are the fundamental unit of observation in many wildlife sampling problems, including aerial surveys of waterfowl, marine mammals, and ungulates. Explicit accounting of cluster size in models for estimating abundance is necessary because detection of individuals within clusters is not independent and detectability of clusters is likely to increase with cluster size. This induces a cluster size bias in which the average cluster size in the sample is larger than in the population at large. Thus, failure to account for the relationship between delectability and cluster size will tend to yield a positive bias in estimates of abundance or density. I describe a hierarchical modeling framework for accounting for cluster-size bias in animal sampling. The hierarchical model consists of models for the observation process conditional on the cluster size distribution and the cluster size distribution conditional on the total number of clusters. Optionally, a spatial model can be specified that describes variation in the total number of clusters per sample unit. Parameter estimation, model selection, and criticism may be carried out using conventional likelihood-based methods. An extension of the model is described for the situation where measurable covariates at the level of the sample unit are available. Several candidate models within the proposed class are evaluated for aerial survey data on mallard ducks (Anas platyrhynchos).

DELINQUENCY AND THE STRUCTURE OF ADOLESCENT PEER GROUPS*

Science.gov (United States)

Kreager, Derek A.; Rulison, Kelly; Moody, James

2010-01-01

Gangs and group-level processes were once central phenomena for criminological theory and research. By the mid-1970's, however, gang research was primarily displaced by studies of individual behavior using randomized self-report surveys, a shift that also removed groups from the theoretical foreground. In this project, we return to the group level to test competing theoretical claims about delinquent group structure. We use network-based clustering methods to identify 897 friendship groups in two ninth grade cohorts of 27 Pennsylvania and Iowa schools. We then relate group-level measures of delinquency and drinking to network measures of group size, friendship reciprocity, transitivity, structural cohesion, stability, average popularity, and network centrality. We find significant negative correlations between group delinquency and all of our network measures, suggesting that delinquent groups are less solidary and less central to school networks than non-delinquent groups. Further analyses, however, reveal that these correlations are primarily explained by other group characteristics, such as gender composition and socioeconomic status. Drinking behaviors, on the other hand, show net positive associations with most of the network measures, suggesting that drinking groups have higher status and are more internally cohesive than non-drinking groups. Our findings shed light on a longstanding criminological debate by suggesting that any structural differences between delinquent and non-delinquent groups may be attributable to other attributes coincidental with delinquency. In contrast, drinking groups appear to provide peer contexts of greater social capital and cohesion. PMID:21572969

Concepts in sample size determination

Directory of Open Access Journals (Sweden)

Umadevi K Rao

2012-01-01

Full Text Available Investigators involved in clinical, epidemiological or translational research, have the drive to publish their results so that they can extrapolate their findings to the population. This begins with the preliminary step of deciding the topic to be studied, the subjects and the type of study design. In this context, the researcher must determine how many subjects would be required for the proposed study. Thus, the number of individuals to be included in the study, i.e., the sample size is an important consideration in the design of many clinical studies. The sample size determination should be based on the difference in the outcome between the two groups studied as in an analytical study, as well as on the accepted p value for statistical significance and the required statistical power to test a hypothesis. The accepted risk of type I error or alpha value, which by convention is set at the 0.05 level in biomedical research defines the cutoff point at which the p value obtained in the study is judged as significant or not. The power in clinical research is the likelihood of finding a statistically significant result when it exists and is typically set to >80%. This is necessary since the most rigorously executed studies may fail to answer the research question if the sample size is too small. Alternatively, a study with too large a sample size will be difficult and will result in waste of time and resources. Thus, the goal of sample size planning is to estimate an appropriate number of subjects for a given study design. This article describes the concepts in estimating the sample size.

Relative efficiency and sample size for cluster randomized trials with variable cluster sizes.

Science.gov (United States)

You, Zhiying; Williams, O Dale; Aban, Inmaculada; Kabagambe, Edmond Kato; Tiwari, Hemant K; Cutter, Gary

2011-02-01

The statistical power of cluster randomized trials depends on two sample size components, the number of clusters per group and the numbers of individuals within clusters (cluster size). Variable cluster sizes are common and this variation alone may have significant impact on study power. Previous approaches have taken this into account by either adjusting total sample size using a designated design effect or adjusting the number of clusters according to an assessment of the relative efficiency of unequal versus equal cluster sizes. This article defines a relative efficiency of unequal versus equal cluster sizes using noncentrality parameters, investigates properties of this measure, and proposes an approach for adjusting the required sample size accordingly. We focus on comparing two groups with normally distributed outcomes using t-test, and use the noncentrality parameter to define the relative efficiency of unequal versus equal cluster sizes and show that statistical power depends only on this parameter for a given number of clusters. We calculate the sample size required for an unequal cluster sizes trial to have the same power as one with equal cluster sizes. Relative efficiency based on the noncentrality parameter is straightforward to calculate and easy to interpret. It connects the required mean cluster size directly to the required sample size with equal cluster sizes. Consequently, our approach first determines the sample size requirements with equal cluster sizes for a pre-specified study power and then calculates the required mean cluster size while keeping the number of clusters unchanged. Our approach allows adjustment in mean cluster size alone or simultaneous adjustment in mean cluster size and number of clusters, and is a flexible alternative to and a useful complement to existing methods. Comparison indicated that we have defined a relative efficiency that is greater than the relative efficiency in the literature under some conditions. Our measure

The association of body size in early to mid-life with adult urinary 6-sulfatoxymelatonin levels among night shift health care workers.

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Ramin, Cody A; Massa, Jennifer; Wegrzyn, Lani R; Brown, Susan B; Pierre-Paul, Jeffrey; Devore, Elizabeth E; Hankinson, Susan E; Schernhammer, Eva S

2015-05-06

Adult body mass index (BMI) has been associated with urinary melatonin levels in humans; however, whether earlier-life body size is associated with melatonin, particularly among night shift workers, remains unknown. We evaluated associations of birth weight, body shape (or somatotype) at ages 5 and 10, BMI at age 18 and adulthood, weight change since age 18, waist circumference, waist to hip ratio, and height with creatinine-adjusted morning urinary melatonin (6-sulfatoxymelatonin, aMT6s) levels among 1,343 healthy women (aged 32-53 at urine collection, 1996-1999) in the Nurses' Health Study (NHS) II cohort. Using multivariable linear regression, we computed least-square mean aMT6s levels across categories of body size, and evaluated whether these associations were modified by night shift work. Adult BMI was inversely associated with aMT6s levels (mean aMT6s levels = 34 vs. 50 ng/mg creatinine, comparing adult BMI ≥ 30 vs. accounting for adult BMI. Night shifts worked prior to urine collection, whether recent or cumulatively over time, did not modify the association between adult BMI and aMT6s levels (e.g., P interaction = 0.72 for night shifts worked within two weeks of urine collection). Our results suggest that adult BMI, but not earlier measures of body size, is associated with urinary aMT6s levels in adulthood. These observations did not vary by night shift work status, and suggest that adult BMI may be an important mechanism by which melatonin levels are altered and subsequently influence chronic disease risk.

Transient Relative Age Effects across annual age groups in National level Australian Swimming.

Science.gov (United States)

Cobley, Stephen; Abbott, Shaun; Dogramaci, Sera; Kable, Adam; Salter, James; Hintermann, Mirjam; Romann, Michael

2017-12-29

To determine the prevalence, magnitude and transient patterning of Relative Age Effects (RAEs) according to sex and stroke event across all age-groups at the Australian National age swimming Championships. Repeated years of cross-sectional participation data were examined. Participants were 6014 unique male (3185) and female (2829) swimmers (aged 12-18 years) who participated in Freestyle (50, 400m) and/or Breaststroke (100, 200m) at the National age swimming Championships between 2000-2014 (inclusive). RAE prevalence, magnitude and transience were determined using Chi-square tests and Cramer's V estimates for effect size. Odds Ratios (OR) and 95% Confidence Intervals (CI) examined relative age quartile discrepancies. These steps were applied across age-groups and according to sex and each stroke event. Consistent RAEs with large-medium effect sizes were evident for males at 12-15 years of age respectively, and with large-medium effects for females at 12-14 respectively across all four swimming strokes. RAE magnitude then consistently reduced with age across strokes (e.g., Q1 vs. Q4 OR range 16year old males=0.94-1.20; females=0.68-1.41). With few exceptions, by 15-16 years RAEs had typically dissipated; and by 17-18 years, descriptive and significant inverse RAEs emerged, reflecting overrepresentation of relatively younger swimmers. Performance advantages associated with relative age (and thereby likely growth and maturation) are transient. Greater consideration of transient performance and participation in athlete development systems is necessary. This may include revising the emphasis of sport programmes according to developmental stages and delaying forms of athlete selection to improve validity. Copyright © 2018 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Curriculum-Based Handwriting Programs: A Systematic Review With Effect Sizes

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Engel, Courtney; Lillie, Kristin; Zurawski, Sarah; Travers, Brittany G.

2018-01-01

Challenges with handwriting can have a negative impact on academic performance, and these challenges are commonly addressed by occupational therapy practitioners in school settings. This systematic review examined the efficacy of curriculum-based interventions to address children’s handwriting difficulties in the classroom (preschool to second grade). We reviewed and computed effect sizes for 13 studies (11 Level II, 2 Level III) identified through a comprehensive database search. The evidence shows that curriculum-based handwriting interventions resulted in small- to medium-sized improvements in legibility, a commonly reported challenge in this age group. The evidence for whether these interventions improved speed is mixed, and the evidence for whether they improved fluency is insufficient. No clear support was found for one handwriting program over another. These results suggest that curriculum-based interventions can lead to improvements in handwriting legibility, but Level I research is needed to validate the efficacy of these curricula. PMID:29689170

Small Group Research

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McGrath, Joseph E.

1978-01-01

Summarizes research on small group processes by giving a comprehensive account of the types of variables primarily studied in the laboratory. These include group structure, group composition, group size, and group relations. Considers effects of power, leadership, conformity to social norms, and role relationships. (Author/AV)

[Appraisal of occupational stress in different gender, age, work duration, educational level and marital status groups].

Science.gov (United States)

Yang, Xin-Wei; Wang, Zhi-Ming; Jin, Tai-Yi

2006-05-01

This study was conducted to assess occupational stress in different gender, age, work duration, educational level and marital status group. A test of occupational stress in different gender, age, work duration, educational level and marital status group, was carried out with revised occupational stress inventory (OSI-R) for 4278 participants. The results of gender show that there are heavier occupational role, stronger interpersonal and physical strain in male than that in female, and the differences are statistically significant (P 0.05). The occupational stress so as to improve the work ability of different groups. Different measure should be taken to reduce the occupational stress so as to improve the work ability of different groups.

Tree age, fruit size and storage conditions affect levels of ascorbic acid, total phenolic concentrations and total antioxidant activity of 'Kinnow' mandarin juice.

Science.gov (United States)

Khalid, Samina; Malik, Aman U; Khan, Ahmad S; Shahid, Muhammad; Shafique, Muhammad

2016-03-15

Bioactive compounds (ascorbic acid, total phenolics and total antioxidants) are important constituents of citrus fruit juice; however, information with regard to their concentrations and changes in relation to tree age and storage conditions is limited. 'Kinnow' (Citrus nobilis Lour × Citrus deliciosa Tenora) mandarin juice from fruit of three tree ages (6, 18 and 35 years old) and fruit sizes (large, medium and small) were examined for their bioactive compounds during 7 days under ambient storage conditions (20 ± 2 °C and 60-65% relative humidity (RH)) and during 60 days under cold storage (4 ± 1 °C and 75-80% RH) conditions. Under ambient conditions, a reduction in total phenolic concentrations (TPC) and in total antioxidant activity (TAA) was found for the juice from all tree ages and fruit sizes. Overall, fruit from 18-year-old trees had higher mean TPC (95.86 µg mL(-1) ) and TAA (93.68 mg L(-1) ), as compared to 6 and 35-year-old trees. Likewise, in cold storage, TAA decreased in all fruit size groups from 18 and 35-year-old trees. In all tree age and fruit size groups, TPC decreased initially during 15 days of cold storage and then increased gradually with increase in storage duration. Ascorbic acid concentrations showed an increasing trend in all fruit size groups from 35-year-old trees. Overall, during cold storage, fruit from 18-year-old trees maintained higher mean ascorbic acid (33.05 mg 100 mL(-1) ) concentrations, whereas fruit from 6-year-old trees had higher TAA (153.1 mg L(-1) ) and TPC (115.1 µg mL(-1) ). Large-sized fruit had higher ascorbic acid (32.08 mg 100 mL(-1) ) concentrations and TAA (157.5 mg L(-1) ). Fruit from 18-year-old trees maintained higher TPC and TAA under ambient storage conditions, whereas fruit from 6-year-old trees maintained higher TPC and TAA during cold storage. Small-sized fruit had higher TPC after ambient temperature storage, whereas large fruit size showed higher ascorbic acid concentrations and TAA after cold

Analysis of filler particle levels and sizes in dental alginates

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Hugo Lemes Carlo

2010-06-01

Full Text Available The aim of this study was to determine the inorganic filler fractions and sizes of commercially alginates. The inorganic particles volumetric fractions of five alginates - Jeltrate(J, Jeltrate Plus(JP, Jeltrate Chromatic Ortho(JC, Hydrogum(H and Ezact Krom(E were accessed by weighing a previously determined mass of each material in water before and after burning samples at 450 °C for 3 hours. Unsettled materials were soaked in acetone and chloroform and sputter-coated with gold for SEM evaluation of fillers' morphology and size. The results for the volumetric inorganic particle content were (%: J - 48.33, JP - 48.33, JC - 33.79, H - 37.55 and E - 40.55. The fillers presented a circular appearance with helical form and various perforations. Hydrogum fillers looked like cylindrical, perforated sticks. The mean values for fillers size were (μm: J - 12.91, JP - 13.67, JC - 13.44, E - 14.59 and H - 9 (diameter, 8.81 (length. The results of this study revealed differences in filler characteristics that could lead to different results when testing mechanical properties.

Sample size and classification error for Bayesian change-point models with unlabelled sub-groups and incomplete follow-up.

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White, Simon R; Muniz-Terrera, Graciela; Matthews, Fiona E

2018-05-01

Many medical (and ecological) processes involve the change of shape, whereby one trajectory changes into another trajectory at a specific time point. There has been little investigation into the study design needed to investigate these models. We consider the class of fixed effect change-point models with an underlying shape comprised two joined linear segments, also known as broken-stick models. We extend this model to include two sub-groups with different trajectories at the change-point, a change and no change class, and also include a missingness model to account for individuals with incomplete follow-up. Through a simulation study, we consider the relationship of sample size to the estimates of the underlying shape, the existence of a change-point, and the classification-error of sub-group labels. We use a Bayesian framework to account for the missing labels, and the analysis of each simulation is performed using standard Markov chain Monte Carlo techniques. Our simulation study is inspired by cognitive decline as measured by the Mini-Mental State Examination, where our extended model is appropriate due to the commonly observed mixture of individuals within studies who do or do not exhibit accelerated decline. We find that even for studies of modest size ( n = 500, with 50 individuals observed past the change-point) in the fixed effect setting, a change-point can be detected and reliably estimated across a range of observation-errors.

A radiologic study by CT scan of pineal size in cancer patients

International Nuclear Information System (INIS)

Tagliabue, M.; Macchi, I.; Salvini, E.; Lissoni, P.; Tancini, G.; Barni, S.; Crispino, S.

1989-01-01

Alterations in size of the pineal body and melatonin secretion have been observed in cancer patients. The present study was carried out to evaluate pineal dimension in a group of cancer patients and their relation to melatonin blood levels. The study included 70 oncologic patients. As controls, 41 patients with acute or chronic disease other than cancer entered the study. Melatonin serum levels were measured by radioimmunoassay on venous blood samples collected at 9:00 a.m. Pineal size was determined by brain CT scan, by considering the product of the two longest perpendicular diameters, multiplied by the thickness of the stratum. The volume of the pineal body was found to be enlarged in 12/70 (17%) cancer patients, and its mean value was significantly higher than that observed in controls. Melatonin levels were also significantly higher in oncologic patients than in controls. However, there was no correlation between melatonin levels and pineal size in cancer patients. Finally, cancer patients did not show a higher degree of pineal calcifications than controls. The clinical significance of pineal enlargement in cancer patients remains to be understood

Preferences for group dominance track and mediate the effects of macro-level social inequality and violence across societies

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Kunst, Jonas R.; Sidanius, Jim; Thomsen, Lotte

2017-01-01

Whether and how societal structures shape individual psychology is a foundational question of the social sciences. Combining insights from evolutionary biology, economy, and the political and psychological sciences, we identify a central psychological process that functions to sustain group-based hierarchies in human societies. In study 1, we demonstrate that macrolevel structural inequality, impaired population outcomes, socio-political instability, and the risk of violence are reflected in the endorsement of group hegemony at the aggregate population level across 27 countries (n = 41,824): The greater the national inequality, the greater is the endorsement of between-group hierarchy within the population. Using multilevel analyses in study 2, we demonstrate that these psychological group-dominance motives mediate the effects of macrolevel functioning on individual-level attitudes and behaviors. Specifically, across 30 US states (n = 4,613), macrolevel inequality and violence were associated with greater individual-level support of group hegemony. Crucially, this individual-level support, rather than cultural-societal norms, was in turn uniquely associated with greater racism, sexism, welfare opposition, and even willingness to enforce group hegemony violently by participating in ethnic persecution of subordinate out-groups. These findings suggest that societal inequality is reflected in people’s minds as dominance motives that underpin ideologies and actions that ultimately sustain group-based hierarchy. PMID:28484013

Preferences for group dominance track and mediate the effects of macro-level social inequality and violence across societies.

Science.gov (United States)

Kunst, Jonas R; Fischer, Ronald; Sidanius, Jim; Thomsen, Lotte

2017-05-23

Whether and how societal structures shape individual psychology is a foundational question of the social sciences. Combining insights from evolutionary biology, economy, and the political and psychological sciences, we identify a central psychological process that functions to sustain group-based hierarchies in human societies. In study 1, we demonstrate that macrolevel structural inequality, impaired population outcomes, socio-political instability, and the risk of violence are reflected in the endorsement of group hegemony at the aggregate population level across 27 countries ( n = 41,824): The greater the national inequality, the greater is the endorsement of between-group hierarchy within the population. Using multilevel analyses in study 2, we demonstrate that these psychological group-dominance motives mediate the effects of macrolevel functioning on individual-level attitudes and behaviors. Specifically, across 30 US states ( n = 4,613), macrolevel inequality and violence were associated with greater individual-level support of group hegemony. Crucially, this individual-level support, rather than cultural-societal norms, was in turn uniquely associated with greater racism, sexism, welfare opposition, and even willingness to enforce group hegemony violently by participating in ethnic persecution of subordinate out-groups. These findings suggest that societal inequality is reflected in people's minds as dominance motives that underpin ideologies and actions that ultimately sustain group-based hierarchy.

Dependence of micelle size and shape on detergent alkyl chain length and head group.

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Ryan C Oliver

Full Text Available Micelle-forming detergents provide an amphipathic environment that can mimic lipid bilayers and are important tools for solubilizing membrane proteins for functional and structural investigations in vitro. However, the formation of a soluble protein-detergent complex (PDC currently relies on empirical screening of detergents, and a stable and functional PDC is often not obtained. To provide a foundation for systematic comparisons between the properties of the detergent micelle and the resulting PDC, a comprehensive set of detergents commonly used for membrane protein studies are systematically investigated. Using small-angle X-ray scattering (SAXS, micelle shapes and sizes are determined for phosphocholines with 10, 12, and 14 alkyl carbons, glucosides with 8, 9, and 10 alkyl carbons, maltosides with 8, 10, and 12 alkyl carbons, and lysophosphatidyl glycerols with 14 and 16 alkyl carbons. The SAXS profiles are well described by two-component ellipsoid models, with an electron rich outer shell corresponding to the detergent head groups and a less electron dense hydrophobic core composed of the alkyl chains. The minor axis of the elliptical micelle core from these models is constrained by the length of the alkyl chain, and increases by 1.2-1.5 Å per carbon addition to the alkyl chain. The major elliptical axis also increases with chain length; however, the ellipticity remains approximately constant for each detergent series. In addition, the aggregation number of these detergents increases by ∼16 monomers per micelle for each alkyl carbon added. The data provide a comprehensive view of the determinants of micelle shape and size and provide a baseline for correlating micelle properties with protein-detergent interactions.

The number of cultural traits is correlated with female group size but not with male group size in chimpanzee communities.

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Johan Lind

Full Text Available What determines the number of cultural traits present in chimpanzee (Pan troglodytes communities is poorly understood. In humans, theoretical models suggest that the frequency of cultural traits can be predicted by population size. In chimpanzees, however, females seem to have a particularly important role as cultural carriers. Female chimpanzees use tools more frequently than males. They also spend more time with their young, skewing the infants' potential for social learning towards their mothers. In Gombe, termite fishing has been shown to be transmitted from mother to offspring. Lastly, it is female chimpanzees that transfer between communities and thus have the possibility of bringing in novel cultural traits from other communities. From these observations we predicted that females are more important cultural carriers than males. Here we show that the reported number of cultural traits in chimpanzee communities correlates with the number of females in chimpanzee communities, but not with the number of males. Hence, our results suggest that females are the carriers of chimpanzee culture.

Portion size: a qualitative study of consumers' attitudes toward point-of-purchase interventions aimed at portion size.

Science.gov (United States)

Vermeer, Willemijn M; Steenhuis, Ingrid H M; Seidell, Jacob C

2010-02-01

This qualitative study assessed consumers' opinions of food portion sizes and their attitudes toward portion-size interventions located in various point-of-purchase settings targeting overweight and obese people. Eight semi-structured focus group discussions were conducted with 49 participants. Constructs from the diffusion of innovations theory were included in the interview guide. Each focus group was recorded and transcribed verbatim. Data were coded and analyzed with Atlas.ti 5.2 using the framework approach. Results showed that many participants thought that portion sizes of various products have increased during the past decades and are larger than acceptable. The majority also indicated that value for money is important when purchasing and that large portion sizes offer more value for money than small portion sizes. Furthermore, many experienced difficulties with self-regulating the consumption of large portion sizes. Among the portion-size interventions that were discussed, participants had most positive attitudes toward a larger availability of portion sizes and pricing strategies, followed by serving-size labeling. In general, reducing package serving sizes as an intervention strategy to control food intake met resistance. The study concludes that consumers consider interventions consisting of a larger variety of available portion sizes, pricing strategies and serving-size labeling as most acceptable to implement.

Size distributions of various radioactive aerosols in the ground-level atmosphere

Energy Technology Data Exchange (ETDEWEB)

Schumann, G.; Baust, E.

1963-11-15

To know the size spectra of radioactive aerosols is important for many reasons. Among others, the efficiency of measuring devices or biological processes, as for instance, retention in the lungs, depend on particle size.The work described deals mainly with two different components of radioactive aerosols in the atmosphere: the natural radon daughters and the fission products originating from nuclear test explosions.

The relation between fearfulness in young and stress-response in adult laying hens, on individual and group level.

Science.gov (United States)

de Haas, Elske N; Kops, Marjolein S; Bolhuis, J Elizabeth; Groothuis, Ton G G; Ellen, Esther D; Rodenburg, T Bas

2012-10-10

Fearfulness of an individual can affect its sensitivity to stress, while at the same time the social situation in which an animal lives can affect its fear level. It is however unknown what the long-term effects of high fearfulness on sensitivity to stress are, on individual or group level in laying hens. We hypothesize that increased fearfulness at a young age results in increased sensitivity to stress at an adult age, and that this relation can differ between groups, due to differences in group composition. Therefore, we studied the relation between fearfulness in an Open Field (OF) test at six weeks of age and plasma-corticosterone (CORT) levels after a 5-min Manual Restraint test (MR) at 33 weeks of age, and assessed behavior in the home pen. We used birds from a low mortality line, selected for four generations on low mortality due to feather pecking and cannibalism and a control line (n=153 in total, eight pens/line). These lines are known to differ in fearfulness and stress physiology. Chicks from the low mortality line were more active in the OF compared to chicks from the control line. Chicks that showed a fearful response (no walking, no vocalizing) in the OF test had higher CORT at 33 weeks of age than chicks that walked and/or vocalized in the OF test and had higher activity in the home pen as adults. On group level, a passive response in the OF was related to high CORT levels after MR. Presence of at least one fearful bird in a group led to higher CORT in the other group mates compared to birds from groups with no fearful birds present. Birds from groups in which more than 50% of birds had severe comb lesions had higher CORT levels compared to birds from groups with less than 50% of birds affected. High fearfulness of laying hen chicks can on individual level have a long-term effect on stress sensitivity. The presence of fearful birds in a group as well as signs of social instability in a group, indicated by comb lesions, can affect sensitivity to

Serum Bisphenol A Level in Boys with Cryptorchidism: A Step to Male Infertility?

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Marta Diana Komarowska

2015-01-01

Full Text Available Cryptorchidism is the most common congenital birth defect in boys and affects about 2–4% full-term male neonates. Its etiology is multifactorial. Purpose. To evaluate the serum bisphenol A (BPA levels in boys with cryptorchidism and healthy boys and to assess the risk of environmental exposure to BPA using the authors’ questionnaire. The data were acquired from a study on boys with cryptorchidism (n=98 and a control group (n=57. Prior to surgery, all patients had BPA serum levels evaluated. The size, position, rigidity of the testis, and abnormality of the epididymis of the undescended testis were assessed. Parents also completed a questionnaire on the risks of exposure to BPA in everyday life. Results. The testes in both groups were similar in size. The turgor of the undescended testis in the group of boys with cryptorchidism was decreased. Free serum BPA level in cryptorchid boys and in the control group was not statistically significant (p>0.05. The conjugated serum BPA level in cryptorchid boys and in the control group was statistically significant (p≤0.05. Total serum BPA level in cryptorchid boys and in the control group was statistically significant (p<0.05. Serum total BPA level was related with a positive answer about problems with conception (p<0.02. Conclusion. Our study indicated that high serum BPA was associated with cryptorchidism.

Sperm production, testicular size, serum gonadotropins and testosterone levels in Merino and Corriedale breeds.

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Fernandez-Abella, D; Becu-Villalobos, D; Lacau-Mengido, I M; Villegas, N; Bentancur, O

1999-01-01

The relationships between testis size, hormone secretion and sperm production were studied during the spring (December) and autumn (May) in rams of two breeds with different breeding seasons and body weights (Corriedale and Australian Merino) maintained on native pastures and under natural photoperiods in Uruguay. Blood samples were collected at 20-min intervals during a 260-360-min period in 13 rams (four Corriedale, nine Australian Merino) during the late spring and autumn. Rams were weighed and testis size was estimated by orchimetry at each time period. Sperm production was estimated during a 2-week period, 2 months before blood collection and during each week following every blood collection. There was no relationship between testicular size and sperm production measured at the same time, nor between live weight and sperm production. In contrast, testicular volume during the late spring was correlated with sperm production in the autumn (r = 0.65; P = 0.02). The autumn serum LH was higher in Corriedale than in Merino rams. LH pulsatility was unaffected by season, but LH pulse frequency tended to be higher in Corriedale than in Merino rams, particularly in the late spring (2.37 versus 1.56 pulses/6 h; P = 0.08). Serum testosterone concentration was similar in both breeds and seasons. FSH levels were higher in the late spring than in the autumn in both breeds (Corriedale: 2.83 +/- 0.48 versus 2.17 +/- 0.24 ng x mL(-1); Merino: 2.23 +/- 0.24 versus 1.88 +/- 0.17 ng x mL(-1)). FSH and testosterone concentrations during the late spring were positively correlated with autumn sperm production (P = 0.07 and P = 0.03, respectively). In conclusion, the present experiment suggests that LH secretion is not a good parameter for the prediction of sperm production. In contrast, in our conditions (breeds and native pastures) testicular size and testosterone or FSH concentrations from the late spring may be used to predict sperm production in the autumn.

Asymptotic size determines species abundance in the marine size spectrum

DEFF Research Database (Denmark)

Andersen, Ken Haste; Beyer, Jan

2006-01-01

The majority of higher organisms in the marine environment display indeterminate growth; that is, they continue to grow throughout their life, limited by an asymptotic size. We derive the abundance of species as a function of their asymptotic size. The derivation is based on size-spectrum theory......, where population structure is derived from physiology and simple arguments regarding the predator-prey interaction. Using a hypothesis of constant satiation, which states that the average degree of satiation is independent of the size of an organism, the number of individuals with a given size is found...... to be proportional to the weight raised to the power -2.05, independent of the predator/prey size ratio. This is the first time the spectrum exponent has been derived solely on the basis of processes at the individual level. The theory furthermore predicts that the parameters in the von Bertalanffy growth function...

Recursive estimation of the claim rates and sizes in an insurance model

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Lakhdar Aggoun

2004-01-01

Full Text Available It is a common fact that for most classes of general insurance, many possible sources of heterogeneity of risk exist. Premium rates based on information from a heterogeneous portfolio might be quite inadequate. One way of reducing this danger is by grouping policies according to the different levels of the various risk factors involved. Using measure change techniques, we derive recursive filters and predictors for the claim rates and claim sizes for the different groups.

The Effect of Group Counseling Program on 8th Grade Students’ Assertiveness Levels

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İsmail SEÇER

2014-06-01

Full Text Available This study is conducted to determine the effects of group counseling program on elementary school 8th grade students’ assertiveness skills. Study group was formed of 100 students getting educated in Erzurum Kültür Elementary School in 2011-2012 education years. RAE-Rathus Assertiveness Schedule was applied on this group to gather data. 30 students getting lower scores from the inventory have been randomly divided into experimental and control groups. Each group is formed of 15 students. Group counseling program has been carried out for 8 weeks on the experimental group to improve the students’ assertiveness skills. Single-way and two-way analysis of covariance (ANCOVA has been used in the analysis of the data. The data is analyzed with SPSS 19.00. The results of the study show that assertiveness skills of the students who participate in the group counseling program has increased significantly compared to the control group and to the preexperimental circumstances. Besides, it is determined that the change observed in the experimental group has been occurred separately from the age and socio-economic level variables, and it is determined with the monitoring test applied after four months that this affect is continued. According to this result, it can be said that the applied group counseling program is an effective means to improve the assertiveness skills of elementary school students

Comparison of the Effect of Noise Levels on Stress Response in Two Different Operation Groups in an Orthopedic Surgery Room

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Hasibe Baytan Yildiz

2016-09-01

Full Text Available Aim: The aim of this randomized, single-blinded study was to evaluate the effects of noise on hemodynamic and neuroendocrine stress response by measuring the level of noise in the surgery rooms of patients undergoing knee operations under neuroaxial anesthesia. Gerec ve Yontem: We compared patient responses from two groups of patients: those undergoing knee operations in a surgery room where the noise level (measured in decibels is high, and those undergoing meniscus operations in a surgery room with lower noise levels. The STAI, the State-Trait Anxiety Inventory (STAI-1, and the anxiety test (STAI-2wereperformed at preoperative and postoperative periods. 20 ml of blood sample was taken for basal, intraoperative 30th minute, and postoperative 1st hour measurements. Systolic, diastolic, and mean arterial blood pressures were found to be higher in the high noise level group. ACTH levels were increased during the early postoperative period and became normal during the late postoperative period in the high noise level group whereas ACTH levels were significantly decreased in the low-noise level group. Basal cortisol levels were significantly higher in the high noise level group. HCRP, an inflammatory response mediator was found to be decreased in both groups. Early and late blood glucose levels were significantly higher in the high noise group. There was a greater increase in early and late blood glucose levels in the high noise group. In the postoperative period, although the state-trait anxiety inventory (STAI-2 levels being higher in patients subject to noisier environment determines how people feel independent of the conditions and state they are in, this result made us consider that the noise the patients were subjected to in the intraoperative period may cause a stress response. Discussion: As a result we believe that standard noise levels should be achieved by reducing the factors causing high noise levels in the operating room. This will

A flexible method for multi-level sample size determination

International Nuclear Information System (INIS)

Lu, Ming-Shih; Sanborn, J.B.; Teichmann, T.

1997-01-01

This paper gives a flexible method to determine sample sizes for both systematic and random error models (this pertains to sampling problems in nuclear safeguard questions). In addition, the method allows different attribute rejection limits. The new method could assist achieving a higher detection probability and enhance inspection effectiveness

Savings and credit: women's informal groups as models for change in developing countries.

Science.gov (United States)

Wickrama, K A; Keith, P M

1994-04-01

The aim of this research was to examine the financial success of newly formed women's groups involved in Sri Lanka's Hambantota Integrated Rural Development Program (HIRDEP). The project was initiated in July 1986 with 20 trained social mobilizers, who were each assigned to a village community of about 100 families. Mobilizers were selected from village volunteers involved in development activities. The study population included 78 women's groups, with an average size of 7 persons, from 19 villages with populations under the poverty level and people receiving food stamps. Measures of group performance included the exchange of labor among group members, the collective purchase of raw materials and consumer goods, and collective marketing. Service use was differentiated by extension services, inputs, assets, and general benefits. Financial activity was measured as the rupee size of the fund and amounts of loans. 54 groups were engaged in nonfarm activity, and most groups had women social mobilizers. About 50% of women's groups had received all four service types. Funding ranged from Rs. 240 to Rs. 9500. The average of the credit loans per month was Rs. 408 per group. 85% of the loans were used for production, investment, or repayment of old loans. Younger age groups affected the slower growth of funds but were more efficient in loaning money, acquiring services, and marketing activities collectively. Young social mobilizers were associated with efficiency of credit disbursement. Diversity of collective activities was related to the size and growth rate of funds. Multivariate analysis revealed that the growth rate of funds was primarily related to the personal income of members and the level of training of social mobilizers. Members were able to obtain loans equal to about 50% of their monthly income at an average interest rate of about 5%, which was three to four times less than normally available. 47% of the variance in the size of the fund was explained by average

Sauropod dinosaurs evolved moderately sized genomes unrelated to body size.

Science.gov (United States)

Organ, Chris L; Brusatte, Stephen L; Stein, Koen

2009-12-22

Sauropodomorph dinosaurs include the largest land animals to have ever lived, some reaching up to 10 times the mass of an African elephant. Despite their status defining the upper range for body size in land animals, it remains unknown whether sauropodomorphs evolved larger-sized genomes than non-avian theropods, their sister taxon, or whether a relationship exists between genome size and body size in dinosaurs, two questions critical for understanding broad patterns of genome evolution in dinosaurs. Here we report inferences of genome size for 10 sauropodomorph taxa. The estimates are derived from a Bayesian phylogenetic generalized least squares approach that generates posterior distributions of regression models relating genome size to osteocyte lacunae volume in extant tetrapods. We estimate that the average genome size of sauropodomorphs was 2.02 pg (range of species means: 1.77-2.21 pg), a value in the upper range of extant birds (mean = 1.42 pg, range: 0.97-2.16 pg) and near the average for extant non-avian reptiles (mean = 2.24 pg, range: 1.05-5.44 pg). The results suggest that the variation in size and architecture of genomes in extinct dinosaurs was lower than the variation found in mammals. A substantial difference in genome size separates the two major clades within dinosaurs, Ornithischia (large genomes) and Saurischia (moderate to small genomes). We find no relationship between body size and estimated genome size in extinct dinosaurs, which suggests that neutral forces did not dominate the evolution of genome size in this group.

Cluster size statistic and cluster mass statistic: two novel methods for identifying changes in functional connectivity between groups or conditions.

Science.gov (United States)

Ing, Alex; Schwarzbauer, Christian

2014-01-01

Functional connectivity has become an increasingly important area of research in recent years. At a typical spatial resolution, approximately 300 million connections link each voxel in the brain with every other. This pattern of connectivity is known as the functional connectome. Connectivity is often compared between experimental groups and conditions. Standard methods used to control the type 1 error rate are likely to be insensitive when comparisons are carried out across the whole connectome, due to the huge number of statistical tests involved. To address this problem, two new cluster based methods--the cluster size statistic (CSS) and cluster mass statistic (CMS)--are introduced to control the family wise error rate across all connectivity values. These methods operate within a statistical framework similar to the cluster based methods used in conventional task based fMRI. Both methods are data driven, permutation based and require minimal statistical assumptions. Here, the performance of each procedure is evaluated in a receiver operator characteristic (ROC) analysis, utilising a simulated dataset. The relative sensitivity of each method is also tested on real data: BOLD (blood oxygen level dependent) fMRI scans were carried out on twelve subjects under normal conditions and during the hypercapnic state (induced through the inhalation of 6% CO2 in 21% O2 and 73%N2). Both CSS and CMS detected significant changes in connectivity between normal and hypercapnic states. A family wise error correction carried out at the individual connection level exhibited no significant changes in connectivity.

Measurement Error Correction Formula for Cluster-Level Group Differences in Cluster Randomized and Observational Studies

Science.gov (United States)

Cho, Sun-Joo; Preacher, Kristopher J.

2016-01-01

Multilevel modeling (MLM) is frequently used to detect cluster-level group differences in cluster randomized trial and observational studies. Group differences on the outcomes (posttest scores) are detected by controlling for the covariate (pretest scores) as a proxy variable for unobserved factors that predict future attributes. The pretest and…

OCCUPATIONAL BURNOUT LEVELS OF ACADEMIC STAFF: TURKEY-MALTA STUDY GROUP SAMPLE

OpenAIRE

Demirtas, Cagri; Kapusuzoglu, Saduman

2016-01-01

The study group of this survey comprises of 185academic staff working in the University, Faculty of Education and Faculty ofEconomics and Administrative Sciences, in Turkey, and Malta University, Facultyof Education and Faculty of Economy, Management and Accounting. This study is adescriptive survey model, in which the assessment tool of Maslach BurnoutInventory is used. The burnout levels of academic personnel are investigated interm of gender, age and Faculty variables. As a result, it was ...

Calculating and reporting effect sizes on scientific papers (1: p < 0.05 limitations in the analysis of mean differences of two groups

Directory of Open Access Journals (Sweden)

Helena Espirito Santo

2015-02-01

Since p-values from the results of the statistical tests do not indicate the magnitude or importance of a difference, then effect sizes (ES should reported. In fact, ES give meaning to statistical tests; emphasize the power of statistical tests; reduce the risk of interpret mere sampling variation as real relationship; can increase the reporting of “non-significant"results, and allow the accumulation of knowledge from several studies using meta-analysis. Thus, the objectives of this paper are to present the limits of the significance level; describe the foundations of presentation of ES of statistical tests to analyze differences between two groups; present the formulas to calculate directly ES, providing examples of our own previous studies; show how to calculate confidence intervals; provide the conversion formulas for the review of the literature; indicate how to interpret the ES; and show that, although interpretable, the meaning (small, medium or large effect for an arbitrary metric could be inaccurate, requiring that interpretation should be made in the context of the research area and in the context of real world variables.

Social media in communicating health information: an analysis of Facebook groups related to hypertension.

Science.gov (United States)

Al Mamun, Mohammad; Ibrahim, Hamza M; Turin, Tanvir Chowdhury

2015-01-29

We studied Facebook groups related to hypertension to characterize their objectives, subject matter, member sizes, geographical boundaries, level of activity, and user-generated content. We performed a systematic search among open Facebook groups using the keywords "hypertension," "high blood pressure," "raised blood pressure," and "blood pressure." We extracted relevant data from each group's content and developed a coding and categorizing scheme for the whole data set. Stepwise logistic regression was used to explore factors independently associated with each group's level of activity. We found 187 hypertension-related Facebook groups containing 8,966 members. The main objective of most (59.9%) Facebook groups was to create hypertension awareness, and 11.2% were created primarily to support patients and caregivers. Among the top-displayed, most recent posts (n = 164), 21.3% were focused on product or service promotion, whereas one-fifth of posts were related to hypertension-awareness information. Each Facebook group's level of activity was independently associated with group size (adjusted odds ratio [AOR], 1.02; 95% confidence interval [CI], 1.01-1.03), presence of "likes" on the most recent wall post (AOR, 3.55, 95% CI, 1.41-8.92), and presence of attached files on the group wall (AOR, 5.01, 95% CI, 1.25-20.1). The primary objective of most of the hypertension-related Facebook groups observed in this study was awareness creation. Compared with the whole Facebook community, the total number of hypertension-related Facebook groups and their users was small and the groups were less active.

Ricinus communis agglutinin-mediated agglutination and fusion of glycolipid-containing phospholipid vesicles: effect of carbohydrate head group size, calcium ions, and spermine.

Science.gov (United States)

Hoekstra, D; Düzgüneş, N

1986-03-25

The glycolipids galactosylcerebroside (GalCer), lactosylceramide (LacCer), and trihexosylceramide (Gb3) were inserted into phospholipid vesicles, consisting of phosphatidylethanolamine and phosphatidic acid. The extent to which their carbohydrate head groups protruded beyond the vesicle surface and their interference with membrane approach were examined by determining vesicle susceptibility toward type I Ricinus communis agglutinin (RCA1) induced agglutination and Ca2+- and spermine-induced aggregation and fusion either in the presence or in the absence of the lectin. The initial agglutination rates increased in the order GalCer much less than LacCer less than Gb3, while a reversed order was obtained for Ca2+- and spermine-induced aggregation and fusion, indicating an enhanced steric interference on close approach of bilayers with increasing head group size. The lectin-mediated agglutination rates for LacCer- and Gb3-containing vesicles increased by an order of magnitude when Ca2+ was also included in the medium, at a concentration that did not induce aggregation per se. Charge neutralization could not account for this observation as the polyvalent cation spermine did not display this synergistic effect with RCA1. Addition of Ca2+ to preagglutinated vesicles substantially reduced the threshold cation concentration for fusion (micromolar vs. millimolar). Quantitatively, this concentration decreased with decreasing carbohydrate head group size, indicating that the head group protrusion determined the interbilayer distance within the vesicle aggregate. The distinct behavior of Ca2+ vs. spermine on RCA1-induced agglutination on the one hand and fusion on the other indicated that Ca2+ regulates the steric orientation of the carbohydrate head group, which appears to be related to its ability to dehydrate the bilayer. As a result, lectin agglutinability becomes enhanced while fusion will be interrupted as the interbilayer distance increases, the threshold head group size

Size effects of latex nanomaterials on lung inflammation in mice

International Nuclear Information System (INIS)

Inoue, Ken-ichiro; Takano, Hirohisa; Yanagisawa, Rie; Koike, Eiko; Shimada, Akinori

2009-01-01

Effects of nano-sized materials (nanomaterials) on sensitive population have not been well elucidated. This study examined the effects of pulmonary exposure to (latex) nanomaterials on lung inflammation related to lipopolysaccharide (LPS) or allergen in mice, especially in terms of their size-dependency. In protocol 1, ICR male mice were divided into 8 experimental groups that intratracheally received a single exposure to vehicle, latex nanomaterials (250 μg/animal) with three sizes (25, 50, and 100 nm), LPS (75 μg/animal), or LPS plus latex nanomaterials. In protocol 2, ICR male mice were divided into 8 experimental groups that intratracheally received repeated exposure to vehicle, latex nanomaterials (100 μg/animal), allergen (ovalbumin: OVA; 1 μg/animal), or allergen plus latex nanomaterials. In protocol 1, latex nanomaterials with all sizes exacerbated lung inflammation elicited by LPS, showing an overall trend of amplified lung expressions of proinflammatory cytokines. Furthermore, LPS plus nanomaterials, especially with size less than 50 nm, significantly elevated circulatory levels of fibrinogen, macrophage chemoattractant protein-1, and keratinocyte-derived chemoattractant, and von Willebrand factor as compared with LPS alone. The enhancement tended overall to be greater with the smaller nanomaterials than with the larger ones. In protocol 2, latex nanomaterials with all sizes did not significantly enhance the pathophysiology of allergic asthma, characterized by eosinophilic lung inflammation and Igs production, although latex nanomaterials with less than 50 nm significantly induced/enhanced neutrophilic lung inflammation. These results suggest that latex nanomaterials differentially affect two types of (innate and adaptive immunity-dominant) lung inflammation

The Impact of Intercultural Competency Training on Perceived Levels of Conflict among Multicultural Student Groups

Science.gov (United States)

Miller, Tate

2014-01-01

The purpose of this study, based on a quasi-experimental static group comparison design, was to determine the extent to which intercultural competency (ICC) training might be related to perceived levels of conflict (i.e., disagreements related to cultural misunderstandings and perceptions) among multicultural groups of students who participated in…

Local Control for Intermediate-Risk Rhabdomyosarcoma: Results From D9803 According to Histology, Group, Site, and Size: A Report From the Children's Oncology Group

Energy Technology Data Exchange (ETDEWEB)

Wolden, Suzanne L., E-mail: woldens@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Lyden, Elizabeth R. [Department of Preventive and Societal Medicine, Nebraska Medical Center, Omaha, Nebraska (United States); Arndt, Carola A. [Department of Pediatric and Adolescent Medicine, Mayo Clinic and Foundation, Rochester, Minnesota (United States); Hawkins, Douglas S. [Division of Hematology/Oncology, Seattle Children' s Hospital, Fred Hutchinson Cancer Research Center, University of Washington, Seattle, Washington (United States); Anderson, James R. [Frontier Science and Technology Research Foundation, Madison, Wisconsin (United States); Rodeberg, David A. [Department of Surgery, East Carolina University, Greenville, North Carolina (United States); Morris, Carol D. [Department of Orthopedic Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland (United States); Donaldson, Sarah S. [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States)

2015-12-01

Purpose: To determine local control according to clinical variables for patients with intermediate-risk rhabdomyosarcoma (RMS) treated on Children's Oncology Group protocol D9803. Patients and Methods: Of 702 patients enrolled, we analyzed 423 patients with central pathology–confirmed group III embryonal (n=280) or alveolar (group III, n=102; group I-II, n=41) RMS. Median age was 5 years. Patients received 42 weeks of VAC (vincristine, dactinomycin, cyclophosphamide) or VAC alternating with VTC (T = topotecan). Local therapy with 50.4 Gy radiation therapy with or without delayed primary excision began at week 12 for group III patients. Patients with group I/II alveolar RMS received 36-41.4 Gy. Local failure (LF) was defined as local progression as a first event with or without concurrent regional or distant failure. Results: At a median follow-up of 6.6 years, patients with clinical group I/II alveolar RMS had a 5-year event-free survival rate of 69% and LF of 10%. Among patients with group III RMS, 5-year event-free survival and LF rates were 70% and 19%, respectively. Local failure rates did not differ by histology, nodal status, or primary site, though there was a trend for increased LF for retroperitoneal (RP) tumors (P=.12). Tumors ≥5 cm were more likely to fail locally than tumors <5 cm (25% vs 10%, P=.0004). Almost all (98%) RP tumors were ≥5 cm, with no difference in LF by site when the analysis was restricted to tumors ≥5 cm (P=.86). Conclusion: Local control was excellent for clinical group I/II alveolar RMS. Local failure constituted 63% of initial events in clinical group III patients and did not vary by histology or nodal status. The trend for higher LF in RP tumors was related to tumor size. There has been no clear change in local control over RMS studies, including IRS-III and IRS-IV. Novel approaches are warranted for larger tumors (≥5 cm).

Cuff size influences blood pressure measurement in obese children and adolescents

DEFF Research Database (Denmark)

Muhamed, P. K.; Olsen, M. H.; Holm, Jens-Christian

2016-01-01

Introduction: Recently, we established that a group ofobese children and adolescents had a higher blood pressure(BP) than a healthy control group. In the present study, weinvestigate whether the higher BP in the obese group wasinfluenced by BP cuff sizes.Methods: A total of 104 obese patients aged...... sizes had a significant impact on BP measurements.Despite the influence of cuff size, multiple regressionanalyses revealed that systolic BP was 68 mmHg higherand diastolic BP 32 mmHg higher in the obese groupthan in the control group. A step function, i.e. a sudden fallin BP, was seen at the point...... of switching from small to mediumcuff size in the control group, which suggests that systolicBP was overestimated when using small cuff size andunderestimated when using medium cuff size in subjectswith an AC near 23 cm.Conclusions: BP was higher in the obese group than inthe control group although BP...

Role of Estrogens in the Size of Neuronal Somata of Paravaginal Ganglia in Ovariectomized Rabbits

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Laura G. Hernández-Aragón

2017-01-01

Full Text Available We aimed to determine the role of estrogens in modulating the size of neuronal somata of paravaginal ganglia. Rabbits were allocated into control (C, ovariectomized (OVX, and OVX treated with estradiol benzoate (OVX + EB groups to evaluate the neuronal soma area; total serum estradiol (E2 and testosterone (T levels; the percentage of immunoreactive (ir neurons anti-aromatase, anti-estrogen receptor (ERα, ERβ and anti-androgen receptor (AR; the intensity of the immunostaining anti-glial cell line-derived neurotrophic factor (GDNF and the GDNF family receptor alpha type 1 (GFRα1; and the number of satellite glial cells (SGCs per neuron. There was a decrease in the neuronal soma size for the OVX group, which was associated with low T, high percentages of aromatase-ir and neuritic AR-ir neurons, and a strong immunostaining anti-GDNF and anti-GFRα1. The decrease in the neuronal soma size was prevented by the EB treatment that increased the E2 without affecting the T levels. Moreover, there was a high percentage of neuritic AR-ir neurons, a strong GDNF immunostaining in the SGC, and an increase in the SGCs per neuron. Present findings show that estrogens modulate the soma size of neurons of the paravaginal ganglia, likely involving the participation of the SGC.

Wound center facility billing: A retrospective analysis of time, wound size, and acuity scoring for determining facility level of service.

Science.gov (United States)

Fife, Caroline E; Walker, David; Farrow, Wade; Otto, Gordon

2007-01-01

Outpatient wound center facility reimbursement for Medicare beneficiaries can be a challenge to determine and obtain. To compare methods of calculating facility service levels for outpatient wound centers and to demonstrate the advantages of an acuity-based billing system (one that incorporates components of facility work that is non-reimbursable by procedure codes and that represents an activity-based costing approach to medical billing), a retrospective study of 5,098 patient encounters contained in a wound care-specific electronic medical record database was conducted. Approximately 500 patient visits to the outpatient wound center of a Texas regional hospital between April 2003 and November 2004 were categorized by service level in documentation and facility management software. Visits previously billed using a time-based system were compared to the Centers for Medicare and Medicaid Services' proposed three-tiered wound size-based system. The time-based system also was compared to an acuity-based scoring system. The Pearson correlation coefficient between billed level of service by time and estimated level of service by acuity was 0.442 and the majority of follow-up visits were billed as Level 3 and above (on a time level of 1 to 5) , confirming that time is not a surrogate for actual work performed. Wound size also was found to be unrelated to service level (Pearson correlation = 0.017) and 97% of wound areas were billings than extremes; no other method produced this distribution. Hospital-based outpatient wound centers should develop, review, and refine acuity score-based models on which to determine billed level of service.

Examining predator–prey body size, trophic level and body mass across marine and terrestrial mammals

Science.gov (United States)

Tucker, Marlee A.; Rogers, Tracey L.

2014-01-01

Predator–prey relationships and trophic levels are indicators of community structure, and are important for monitoring ecosystem changes. Mammals colonized the marine environment on seven separate occasions, which resulted in differences in species' physiology, morphology and behaviour. It is likely that these changes have had a major effect upon predator–prey relationships and trophic position; however, the effect of environment is yet to be clarified. We compiled a dataset, based on the literature, to explore the relationship between body mass, trophic level and predator–prey ratio across terrestrial (n = 51) and marine (n = 56) mammals. We did not find the expected positive relationship between trophic level and body mass, but we did find that marine carnivores sit 1.3 trophic levels higher than terrestrial carnivores. Also, marine mammals are largely carnivorous and have significantly larger predator–prey ratios compared with their terrestrial counterparts. We propose that primary productivity, and its availability, is important for mammalian trophic structure and body size. Also, energy flow and community structure in the marine environment are influenced by differences in energy efficiency and increased food web stability. Enhancing our knowledge of feeding ecology in mammals has the potential to provide insights into the structure and functioning of marine and terrestrial communities. PMID:25377460

Influence of Group Size on the Success of Wolves Hunting Bison

OpenAIRE

MacNulty, Daniel R.; Tallian, Aimee; Stahler, Daniel R.; Smith, Douglas W.

2014-01-01

An intriguing aspect of social foraging behaviour is that large groups are often no better at capturing prey than are small groups, a pattern that has been attributed to diminished cooperation (i.e., free riding) in large groups. Although this suggests the formation of large groups is unrelated to prey capture, little is known about cooperation in large groups that hunt hard-to-catch prey. Here, we used direct observations of Yellowstone wolves (Canis lupus) hunting their most formidable prey...

Hierarchical complexity and the size limits of life.

Science.gov (United States)

Heim, Noel A; Payne, Jonathan L; Finnegan, Seth; Knope, Matthew L; Kowalewski, Michał; Lyons, S Kathleen; McShea, Daniel W; Novack-Gottshall, Philip M; Smith, Felisa A; Wang, Steve C

2017-06-28

Over the past 3.8 billion years, the maximum size of life has increased by approximately 18 orders of magnitude. Much of this increase is associated with two major evolutionary innovations: the evolution of eukaryotes from prokaryotic cells approximately 1.9 billion years ago (Ga), and multicellular life diversifying from unicellular ancestors approximately 0.6 Ga. However, the quantitative relationship between organismal size and structural complexity remains poorly documented. We assessed this relationship using a comprehensive dataset that includes organismal size and level of biological complexity for 11 172 extant genera. We find that the distributions of sizes within complexity levels are unimodal, whereas the aggregate distribution is multimodal. Moreover, both the mean size and the range of size occupied increases with each additional level of complexity. Increases in size range are non-symmetric: the maximum organismal size increases more than the minimum. The majority of the observed increase in organismal size over the history of life on the Earth is accounted for by two discrete jumps in complexity rather than evolutionary trends within levels of complexity. Our results provide quantitative support for an evolutionary expansion away from a minimal size constraint and suggest a fundamental rescaling of the constraints on minimal and maximal size as biological complexity increases. © 2017 The Author(s).

Vacancies and defect levels in III–V semiconductors

KAUST Repository

Tahini, H. A.

2013-08-13

Using electronic structure calculations, we systematically investigate the formation of vacancies in III-V semiconductors (III = Al, Ga, and In and V = P, As, and Sb), for a range of charges ( −3≤q≤3 ) as a function of the Fermi level and under different growth conditions. The formation energies were corrected using the scheme due to Freysoldt et al. [Phys. Rev. Lett. 102, 016402 (2009)] to account for finite size effects. Vacancy formation energies were found to decrease as the size of the group V atom increased. This trend was maintained for Al-V, Ga-V, and In-V compounds. The negative-U effect was only observed for the arsenic vacancy in GaAs, which makes a charge state transition from +1 to –1. It is also found that even under group III rich conditions, group III vacancies dominate in AlSb and GaSb. For InSb, group V vacancies are favoured even under group V rich conditions.

Vacancies and defect levels in III–V semiconductors

KAUST Repository

Tahini, H. A.; Chroneos, Alexander; Grimes, R. W.; Murphy, S. T.; Schwingenschlö gl, Udo

2013-01-01

Using electronic structure calculations, we systematically investigate the formation of vacancies in III-V semiconductors (III = Al, Ga, and In and V = P, As, and Sb), for a range of charges ( −3≤q≤3 ) as a function of the Fermi level and under different growth conditions. The formation energies were corrected using the scheme due to Freysoldt et al. [Phys. Rev. Lett. 102, 016402 (2009)] to account for finite size effects. Vacancy formation energies were found to decrease as the size of the group V atom increased. This trend was maintained for Al-V, Ga-V, and In-V compounds. The negative-U effect was only observed for the arsenic vacancy in GaAs, which makes a charge state transition from +1 to –1. It is also found that even under group III rich conditions, group III vacancies dominate in AlSb and GaSb. For InSb, group V vacancies are favoured even under group V rich conditions.

Effect of individual and group housing of mice on the level of radioresistance

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Dorozhkina O.V.

2015-12-01

Full Text Available Aim: to examine the effect of individual and group housing of mice on radioresistance. Material and methods. Effects of individual and group housing of mice on immunity and blood systems were studied on ICR (CD-1 and C57BI6 male mice before and after proton irradiation. Results. Group housing of intact animals resulted in a decline in the number of nucleated cells in the femur bone marrow and thymus mass. The irradiation with proton with energy of 171 MeV at a dose of 1 Gy causes a statistically significant greater reduction of the number of nucleated cells in the femur bone marrow in group-housed mice. A trend toward greater safety of the number of leukocytes in the peripheral blood and higher proliferative activity of bone marrow cells, as well as lower level of aberrant mitoses have been noted in individually-housed mice. Reduction processes in the recovery period of radiation sickness take place at a greater rate in group-housed mice. Conclusion. Group housing of male mice causes increased sensitivity of the blood and immunity systems to the effects of radiation and at the same time accelerates processes of radiation recovery.

Do class size effects differ across grades?

DEFF Research Database (Denmark)

Nandrup, Anne Brink

size cap that creates exogenous variation in class sizes. Significant (albeit modest) negative effects of class size increases are found for children on primary school levels. The effects on math abilities are statistically different across primary and secondary school. Larger classes do not affect......This paper contributes to the class size literature by analyzing whether short-run class size effects are constant across grade levels in compulsory school. Results are based on administrative data on all pupils enroled in Danish public schools. Identification is based on a government-imposed class...

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…

Reported parental characteristics in relation to trait depression and anxiety levels in a non-clinical group.

Science.gov (United States)

Parker, G

1979-09-01

Care and overprotection appear to reflect the principal dimensions underlying parental behaviours and attitudes. In previous studies of neurotically depressed patients and of a non-clinical group, subjects who scored their parents as lacking in care and/or overprotective had the greater depressive experience. The present study of another non-clinical group (289 psychology students) replicated those findings in regard to trait depression levels. In addition, associations between those parental dimensions and trait anxiety scores were demonstrated. Multiple regression analyses established that 9-10% of the variance in mood scores was accounted for by scores on those parental dimensions. Low maternal care scores predicted higher levels of both anxiety and depression, while high maternal overprotection scores predicted higher levels of anxiety but not levels of depression. Maternal influences were clearly of greater relevance than paternal influences.

Within- and between-individual variation in energy and nutrient intake in Japanese adults: effect of age and sex differences on group size and number of records required for adequate dietary assessment.

Science.gov (United States)

Fukumoto, Azusa; Asakura, Keiko; Murakami, Kentaro; Sasaki, Satoshi; Okubo, Hitomi; Hirota, Naoko; Notsu, Akiko; Todoriki, Hidemi; Miura, Ayako; Fukui, Mitsuru; Date, Chigusa

2013-01-01

Information on within- and between-individual variation in energy and nutrient intake is critical for precisely estimating usual dietary intake; however, data from Japanese populations are limited. We used dietary records to examine within- and between-individual variation by age and sex in the intake of energy and 31 selected nutrients among Japanese adults. We also calculated the group size required to estimate mean intake for a group and number of days required both to rank individuals within a group and to assess an individual's usual intake, all with appropriate arbitrary precision. A group of Japanese women (younger: 30-49 years, n = 58; older: 50-69 years, n = 63) and men (younger: 30-49 years, n = 54; older: 50-76 years, n = 67) completed dietary records for 4 nonconsecutive days in each season (16 days in total). Coefficients of within-individual variation and between-individual variation were generally larger in the younger group than in the older group and in men as compared with women. The group size required to estimate a group's mean intake, and number of days required to assess an individual's usual intake, were generally larger for the younger group and for men. In general, a longer period was required to rank women and older adults. In a group of Japanese adults, coefficients of within-individual variation and between-individual variation, which were used to estimate the group size and number of records required for adequate dietary assessment, differed by age, sex, and nutrient.

Effect of Metformin-sustained Release Therapy on Low-density Lipoprotein Size and Adiponectin in the South Indian Women with Polycystic Ovary Syndrome.

Science.gov (United States)

Kumar, D Rama Nagendra; Seshadri, Krishna G; Pandurangi, Monna

2017-01-01

The aim of the study is to compare surrogate markers of cardiovascular disease (CVD) risk, such as adiponectin (APN) levels and low-density lipoprotein (LDL) size, before and after sustained release metformin (Met-SR) therapy in women with polycystic ovarian syndrome (PCOS). Sixty women with PCOS and sixty age-matched controls in the age group 18-45 years were recruited after obtaining informed consent. Women with PCOS were initiated on Met-SR 1 g orally, which was increased to 1.5 g after 2 weeks and continued up to 24 weeks. Demographic data along with family history of type 2 diabetes mellitus, PCOS, and CVD were collected. Lipid profile plasma APN levels and LDL size were measured before and after therapy in the PCOS group. Data analysis was performed using the GraphPad Prism-5 software. Women with PCOS had greater dyslipidemia, lower APN level and LDL size, and increased lipid accumulating product index as compared to controls. After 6 months of Met-SR therapy, women with PCOS demonstrated significant increase in plasma APN levels and LDL size and significant decrease in weight, waist-hip ratio (WHR), waist circumference (WC), and blood pressure (BP). A significant decrease was observed in body mass index (BMI) in the overweight and obese PCOS subgroups. Met-SR increases LDL size, APN concentration and decreases weight, WC, WHR, and BP in patients with PCOS. Met-SR may have salutary effects on LDL particle size through effects on APN levels in women with PCOS.

Exploring Secondary Students' Epistemological Features Depending on the Evaluation Levels of the Group Model on Blood Circulation

Science.gov (United States)

Lee, Shinyoung; Kim, Heui-Baik

2014-01-01

The purpose of this study is to identify the epistemological features and model qualities depending on model evaluation levels and to explore the reasoning process behind high-level evaluation through small group interaction about blood circulation. Nine groups of three to four students in the eighth grade participated in the modeling practice.…

Size stratification in a Gilbert delta due to a varying base level: flume experiments.

Science.gov (United States)

Chavarrias, Victor; Orru, Clara; Viparelli, Enrica; Vide, Juan Pedro Martin; Blom, Astrid

2014-05-01

mobile armor that covered the fluvial reach. This led to an initial coarsening of the brinkpoint load (and foreset deposit). Once the mobile armour was eroded, base level fall led to degradation of the finer substrate, which resulted in a fining of the brinkpoint load and foreset deposit. The relation between the sediment size stratification and the base level change may be used for the reconstruction of the paleo sea level from the stratigraphy of ancient Gilbert deltas.

The Impact of Solution-Focused Brief Group Psychological Counseling on University Students’ Burnout Levels

Directory of Open Access Journals (Sweden)

Azmi Bayram Ilbay

2014-12-01

Full Text Available This research was done to analyze the effects of Coping with Burnout Program, developed on the basis of Solution-Focused Brief Therapy on the burnout levels of university students. To select the subjects that would participate in the research, Maslach Burnout Inventory­­–Student Survey was applied on 461 university students from the University of Sakarya. As a result of pre-interviews, 24 students who had experienced student burnout voluntarily participated in a Coping with Burnout Program. The students were randomly appointed to one of the experimental and control groups. At this stage, a six-session Coping with Burnout Program developed by the researcher was applied on the students from the experimental group. No application was performed on the students from the control group. A 2x3 design (experimental/ control groups X pretest/ posttest/ follow up was used in the research. The scores from the Maslach Burnout Inventory–Student Survey formed the dependent variable of the research, and the application of Coping with Burnout Program formed the independent variable of the research. The scale used in the research was applied on the groups as pretest two weeks before the sessions started, and as posttest two weeks after the sessions ended, and as follow-up two months after the posttest in order to determine the resistance of the experimental process. In the analysis of the data obtained through these processes, two-way analysis of variance (ANOVA was used to determine whether or not there was a significant difference between groups and the survey. The data obtained through the research proved that the Coping with Burnout Program decreased the burnout levels of the students in the experimental group as were determined with the Maslach Burnout Inventory–Student Survey, and follow up tests showed that the situation remained the same. It was seen that there was no significant difference between the scores of the participants of the control

Comparative Genomics of the Bacterial Genus Streptococcus Illuminates Evolutionary Implications of Species Groups

Science.gov (United States)

Gao, Xiao-Yang; Zhi, Xiao-Yang; Li, Hong-Wei; Klenk, Hans-Peter; Li, Wen-Jun

2014-01-01

Members of the genus Streptococcus within the phylum Firmicutes are among the most diverse and significant zoonotic pathogens. This genus has gone through considerable taxonomic revision due to increasing improvements of chemotaxonomic approaches, DNA hybridization and 16S rRNA gene sequencing. It is proposed to place the majority of streptococci into “species groups”. However, the evolutionary implications of species groups are not clear presently. We use comparative genomic approaches to yield a better understanding of the evolution of Streptococcus through genome dynamics, population structure, phylogenies and virulence factor distribution of species groups. Genome dynamics analyses indicate that the pan-genome size increases with the addition of newly sequenced strains, while the core genome size decreases with sequential addition at the genus level and species group level. Population structure analysis reveals two distinct lineages, one including Pyogenic, Bovis, Mutans and Salivarius groups, and the other including Mitis, Anginosus and Unknown groups. Phylogenetic dendrograms show that species within the same species group cluster together, and infer two main clades in accordance with population structure analysis. Distribution of streptococcal virulence factors has no obvious patterns among the species groups; however, the evolution of some common virulence factors is congruous with the evolution of species groups, according to phylogenetic inference. We suggest that the proposed streptococcal species groups are reasonable from the viewpoints of comparative genomics; evolution of the genus is congruent with the individual evolutionary trajectories of different species groups. PMID:24977706

Food prices and consumer demand: differences across income levels and ethnic groups.

Directory of Open Access Journals (Sweden)

Cliona Ni Mhurchu

Full Text Available BACKGROUND: Targeted food pricing policies may improve population diets. To assess their effects on inequalities, it is important to determine responsiveness to price changes across income levels and ethnic groups. OBJECTIVE: Our goal was to estimate price elasticity (PE values for major commonly consumed food groups in New Zealand, by income and ethnicity. PE values represent percentage change in demand associated with 1% change in price of that good (own-PE or another good (cross-PE. DESIGN: We used food expenditure data from national household economic surveys in 2007/08 and 2009/10 and Food Price Index data from 2007 and 2010. Adopting an Almost Ideal Demand System approach, own-PE and cross-PE estimates were derived for 24 food categories, household income quintiles, and two ethnic groups (Māori and non-Māori. RESULTS: Own-PE estimates (with two exceptions ranged from -0.44 to -1.78. Cross-PE estimates were generally small; only 31% of absolute values were greater than 0.10. Excluding the outlier 'energy drinks', nine of 23 food groups had significantly stronger own-PEs for the lowest versus highest income quintiles (average regression-based difference across food groups -0.30 (95% CI -0.62 to 0.02. Six own-PEs were significantly stronger among Māori; the average difference for Māori: non-Māori across food groups was -0.26 (95% CI -0.52 to 0.00. CONCLUSIONS: Food pricing policies have potential to improve population diets. The greater sensitivity of low-income households and Māori to price changes suggests the beneficial effects of such policies on health would be greatest for these groups.

Ovarian size and response to laparoscopic ovarian electro-cauterization in polycystic ovarian disease.

Science.gov (United States)

Alborzi, S; Khodaee, R; Parsanejad, M E

2001-09-01

To evaluate endocrine and ovulatory changes in polycystic ovarian disease (PCOD) in relation to patients' ovarian size. Three hundred and seventy-one women with clomiphene citrate-resistant PCOD underwent laparoscopic ovarian cauterization [type I or typical with ovarian volume >8 cm(3) or cross-sectional area >10 cm(2) (n=211), type II with normal size ovary (n=160)]. Serum levels of LH, FSH, DHEAS, PRL, and T before and 10 days after ovarian cautery, spontaneous and induced ovulation and pregnancy rates were compared. Both groups responded to therapy in a similar manner, with a marked decrease in LH, FSH, DHEAS and T levels, with ovulation rates in type I 90.99%, type II 88.75% and pregnancy rates, 73.45% and 71.25%, respectively, with no statistical differences. Hormonal changes, ovulation and pregnancy rates were similar in the two types of PCOD, therefore it can be concluded that ovarian size is not a prognostic factor for response of PCOD patients to laparoscopic ovarian electro-cauterization.

Class size, type of exam and student achievement

DEFF Research Database (Denmark)

Madsen, Erik

Education as a road to growth has been on the political agenda in recent years and promoted not least by the institutions of higher education. At the same time the universities have been squeezed for resources for a long period and the average class size has increased as a result. However......, the production technology for higher education is not well known and this study highlights the relation between class size and student achievement using a large dataset of 80.000 gradings from the Aarhus School of Business. The estimations show a large negative effect of larger classes on the grade level...... of students. The type of exam also has a large and significant effect on student achievements and oral exam, take-home exam and group exam reward the student with a significantly higher grade compared with an on-site written exam....

Class Size, Type of Exam and Student Achievement

DEFF Research Database (Denmark)

Madsen, Erik Strøjer

2011-01-01

Education as a road to growth has been on the political agenda in recent years and promoted not least by the institutions of higher education. At the same time the universities have been squeezed for resources for a long period and the average class size has increased as a result. However......, the production technology for higher education is not well known and this study highlights the relation between class size and student achievement using a large dataset of 80.000 gradings from the Aarhus School of Business. The estimations show a large negative effect of larger classes on the grade level...... of students. The type of exam also has a large and significant effect on student achievements and oral exam, take-home exam and group exam reward the student with a significantly higher grade compared with an on-site written exam....

Examining predator-prey body size, trophic level and body mass across marine and terrestrial mammals.

Science.gov (United States)

Tucker, Marlee A; Rogers, Tracey L

2014-12-22

Predator-prey relationships and trophic levels are indicators of community structure, and are important for monitoring ecosystem changes. Mammals colonized the marine environment on seven separate occasions, which resulted in differences in species' physiology, morphology and behaviour. It is likely that these changes have had a major effect upon predator-prey relationships and trophic position; however, the effect of environment is yet to be clarified. We compiled a dataset, based on the literature, to explore the relationship between body mass, trophic level and predator-prey ratio across terrestrial (n = 51) and marine (n = 56) mammals. We did not find the expected positive relationship between trophic level and body mass, but we did find that marine carnivores sit 1.3 trophic levels higher than terrestrial carnivores. Also, marine mammals are largely carnivorous and have significantly larger predator-prey ratios compared with their terrestrial counterparts. We propose that primary productivity, and its availability, is important for mammalian trophic structure and body size. Also, energy flow and community structure in the marine environment are influenced by differences in energy efficiency and increased food web stability. Enhancing our knowledge of feeding ecology in mammals has the potential to provide insights into the structure and functioning of marine and terrestrial communities. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Effects of an integrated geriatric group balance class within an entry-level Doctorate of Physical Therapy program on students’ perceptions of geriatrics and geriatric education in the United States

Directory of Open Access Journals (Sweden)

Jennifer C. Reneker

2016-10-01

Full Text Available This study was aimed at determining the effect of an integrated group balance class for community-dwelling older adults within entry-level physical therapist coursework on student perceptions of geriatric physical therapy and geriatric physical therapy education. Twenty-nine Doctor of Physical Therapy (DPT students, 21–33 years old, in their second year of coursework in 2012, participated in an integrated clinical experience with exposure to geriatric patients at an outpatient facility at the Louis Stokes Cleveland Department of Veterans Affairs Medical Center in Akron, Ohio, USA. Student perceptions were collected before and after participation in the 8-week balance class. The Wilcoxon sign-ranked test was used to identify differences in perceptions after participation in the group balance class. Cohen’s d-values were calculated to measure the size of the pre-participation to post-participation effect for each measure. At the conclusion of the group class, the DPT students demonstrated an increase in positive perceptions of geriatric physical therapy in 8 measures, with small effect sizes (d=0.15–0.30. Two perceptions of geriatric physical therapy demonstrated a significant positive increase (P<0.05 with moderate effect sizes (d=0.47 and d=0.50. The students’ perceptions of geriatric education in the curriculum demonstrated a large positive effect for quality (d=1.68 and enjoyment (d=1.96. Positive changes were found in most of the perceptions of geriatrics and geriatric education after participation, suggesting that integrated clinical experiences with geriatric patients are an effective way to positively influence perceptions of physical therapist practice with older adults.

Material size effects on crack growth along patterned wafer-level Cu–Cu bonds

DEFF Research Database (Denmark)

Tvergaard, Viggo; Niordson, Christian Frithiof; Hutchinson, John W.

2013-01-01

together. Crack growth along the bond interface is here studied numerically using finite element analyses. The experiments have shown that plasticity in the Cu films makes a major contribution to the macroscopic interface toughness. To account for the size dependence of the plastic flow a strain gradient...... plasticity model is applied here for the metal. A cohesive zone model is applied to represent the crack growth along the bond between the two Cu films. This cohesive zone model incorporates the effect of higher order stresses in the continuum, such that the higher order tractions on the crack faces decay...... the toughness peak and the subsequent plateau level are highly sensitive to the value of the characteristic material length. A small material length, relative to the thickness of the Cu film, gives high toughness whereas a length comparable to the film thickness gives much reduced crack growth resistance...

Effects of supplementation level and particle size of alfalfa hay on growth characteristics and rumen development in dairy calves

NARCIS (Netherlands)

Mirzaei, M.; Khorvash, M.; Ghorbani, G.R.; Kazemi-Bonchenari, M.; Riasi, A.; Nabipour, A.; Borne, van den J.J.G.C.

2015-01-01

The aim of this study was to assess the effects of particle size (PS) of alfalfa hay on growth characteristics and rumen development in dairy calves at two levels of alfalfa supplementation. Fifty newborn dairy calves (42.7 ± 2.2 kg BW) were used in a 2 × 2 factorial arrangement with the factors

Comparison of Selected Protein Levels in Tumour and Surgical Margin in a Group of Patients with Oral Cavity Cancer.

Science.gov (United States)

Strzelczyk, Joanna Katarzyna; Gołąbek, Karolina; Cuber, Piotr; Krakowczyk, Łukasz; Owczarek, Aleksander Jerzy; Fronczek, Martyna; Choręża, Piotr; Hudziec, Edyta; Ostrowska, Zofia

2017-08-01

Oral cavity cancer belongs to head-and-neck squamous cell carcinoma group. The purpose of the study was to assess the levels of certain proteins in a tumour and surgical margin in a group of patients with oral cavity cancer. The levels of DAPK1, MGMT, CDH1, SFRP1, SFRP2, RORA, TIMP3, p16, APC and RASSF1 proteins were measured by ELISA in tissue homogenates. The protein levels of DAPK1, MGMT, CDH1, SFRP2 and RASSF1 were significantly higher in tumour tissue than in the margin, contrary to TIMP3 which was lower in the tumour itself. DAPK1 level in the tumour was significantly higher in females than in males, the MGMT and p16 levels were lower in the tumours with lymph node metastasis (N1 + N2) than in N0 samples. The CDH1 expression was higher in a group with smoking habits, whereas TIMP3 was lower in this group. Changes in the levels of proteins in tumour and surgical margin may be either reflective of tumour occurrence and development, or they might be also responsible for the progress and reoccurrence of the disease. Levels of the studied proteins might be good prognostic factors; however, further studies are required.

The optimum size of rotating qarḍ ḥasan savings and credit associations

Directory of Open Access Journals (Sweden)

Seyed Kazem Sadr

2017-07-01

Full Text Available Purpose - Several indigenous credit and savings schemes have been accredited recently in developing countries for the benefit of households and entrepreneurs alike. Famous among them are the Rotating Savings and Credit Associations (ROSCAs that exist in almost all continents currently. The rapid development of ROSCAs and their varied structures in many countries have been the subject of numerous studies. What has not been thoroughly analysed is the optimum size of these associations and the fact that lending and borrowing is without interest. The aim of this paper is to present a model that would determine the optimum size of ROSCAs and deal with the following issues: how the group size varies with changes in the income level of the members, the demand for the loan, the size of the collected loan and its duration. Further, the question of whether or not lending to the association in return for obtaining larger sums is a violation of the qarḍ (loan contract is dealt with, and several Sharīʿah compatible formulations are provided. Design/methodology/approach - Economic analysis has been applied to show the optimum size of Qarḍ Ḥasan Associations (QHAs, which are the Sharīʿah-compliant equivalent of ROSCAs, and the Sharīʿah rules of the qarḍ contract to illustrate the legitimacy of group lending. Findings - The major findings of this study are determination of the optimum size of QHAs, the factors that affect the size and suggestion of alternative legal forms for group financing. Research limitations/implications - Inaccessibility to sources of data to test the hypothesis that has been put forth is the main difficulty encountered when conducting research on the subject. Practical implications - The paper concludes that the development of informal interest-free ROSCAs in both Muslim and non-Muslim countries is an efficient informal microfinance scheme and that it is compatible with Sharīʿah rules. Originality/value - The optimum size

Learning to communicate risk information in groups

Directory of Open Access Journals (Sweden)

Hsuchi Ting

2008-12-01

Full Text Available Despite vigorous research on risk communication, little is known about the social forces that drive these choices. Erev, Wallsten, and Neal (1991 showed that forecasters learn to select verbal or numerical probability estimates as a function of which mode yields on average the larger group payoffs. We extend the result by investigating the effect of group size on the speed with which forecasters converge on the better communication mode. On the basis of social facilitation theory we hypothesized that small groups induce less arousal and anxiety among their members than do large groups when performing new tasks, and therefore that forecasters in small groups will learn the better communication mode more quickly. This result obtained in Experiment 1, which compared groups of size 3 to groups of size 5 or 6. To test whether social loafing rather than social facilitation was mediating the effects, Experiment 2 compared social to personal feedback holding group size constant at 3 members. Learning was faster in the personal feedback condition, suggesting that social facilitation rather than loafing underlay the results.

Home range sizes for burchell's zebra equus burchelli antiquorum from the Kruger National Park

Directory of Open Access Journals (Sweden)

G.L. Smuts

1975-07-01

Full Text Available Annual home range sizes were determined for 49 marked zebra family groups in the Kruger National Park. Sizes varied from 49 to 566 sq. km, the mean for the Park being 164 square kilometre. Mean home range sizes for different zebra sub-populations and biotic areas were found to differ considerably. Present herbivore densities have not influenced intra- and inter-specific tolerance levels to the extent that home range sizes have increased. Local habitat conditions, and particularly seasonal vegetational changes, were found to have the most profound influence on the shape and mean size of home ranges. The large home range sizes obtained in the Kruger Park, when compared to an area such as the Ngorongoro Crater, can be ascribed to a lower carrying capacity with respect to zebra, large portions of the habitat being sub-optimal, either seasonally or annually.

The brain sizes of living elasmobranchii as their organization level indicator. I. General analysis.

Science.gov (United States)

Myagkov, N A

1991-01-01

The relationship between brain and body masses of 64 species and subspecies of modern sharks and skates was investigated. It was established that the level of their encephalization in terms of the polygons of encephalization and the allometry coefficient (alpha), shows quite obviously the general organization level of one or another taxon of sharks and skates. Alpha = 0.56 for the class of cartilaginous fishes, and for the superorder of sharks and skates alpha = 0.54 and 0.61, accordingly. For several orders alpha constitutes: sharks--common for relict Hexanchiformes and Heterodontiformes 0.44, Squaliformes 0.43 and Carcharhiniformes 0.52 and skates--Rajiformes 0.44 and Dasyatiformes 0.52. All values are similar to those of other vertebrates and the theoretically calculated value of alpha (0.67). It was established the "place" of present-day Elasmobranchii and all cartilaginous fishes in the evolutionary row of Gnathostomata and Craniata on the developing and relative sizes of CNS, and the corrected alpha value for this particular vertebrate class was specified which was found to be sensationally high also in the works of foreign and native authors (Bauchot et al., 1976; Northcutt, 1978; Ebbesson, 1980; Kreps, 1980).

Characterization of the endomycorrhizal and seven groups of microorganisms in agro systems of the amazon piedmont

International Nuclear Information System (INIS)

Franco Castro, Luis Antonio; Garcia Conde, Mary Ruth

2012-01-01

This study characterized the functional structure, the diversity of the community of endomycorrhizae and population size of seven functional groups of microorganisms in soils under four different uses of land or agro systems (forest, cane, pasture, and cultivation of coffee), the which were located in a production unit in the rural area of Florencia-Caqueta. From samples of surface soil (0-20 cm) were determined agro ecosystems soil physical and chemical properties, the size of populations seven functional groups of microorganisms, the structure of the community to endomycorrhizae (spore density, density mycelium total) and diversity (richness, dominance, equity indices). It was found that the change in natural cover on the land use implications in population size of certain bacterial groups in the structure and functional diversity of endomycorrhizae. Was also be determined the population structure of soil microbiota is particular to each vegetation type and population size is strongly related to levels of soil nutrients, which come from the mineralization of organic matter.

Temporal variability of the bioaerosol background at a subway station: concentration level, size distribution, and diversity of airborne bacteria.

Science.gov (United States)

Dybwad, Marius; Skogan, Gunnar; Blatny, Janet Martha

2014-01-01

Naturally occurring bioaerosol environments may present a challenge to biological detection-identification-monitoring (BIODIM) systems aiming at rapid and reliable warning of bioterrorism incidents. One way to improve the operational performance of BIODIM systems is to increase our understanding of relevant bioaerosol backgrounds. Subway stations are enclosed public environments which may be regarded as potential bioterrorism targets. This study provides novel information concerning the temporal variability of the concentration level, size distribution, and diversity of airborne bacteria in a Norwegian subway station. Three different air samplers were used during a 72-h sampling campaign in February 2011. The results suggested that the airborne bacterial environment was stable between days and seasons, while the intraday variability was found to be substantial, although often following a consistent diurnal pattern. The bacterial levels ranged from not detected to 10(3) CFU m(-3) and generally showed increased levels during the daytime compared to the nighttime levels, as well as during rush hours compared to non-rush hours. The airborne bacterial levels showed rapid temporal variation (up to 270-fold) on some occasions, both consistent and inconsistent with the diurnal profile. Airborne bacterium-containing particles were distributed between different sizes for particles of >1.1 μm, although ∼50% were between 1.1 and 3.3 μm. Anthropogenic activities (mainly passengers) were demonstrated as major sources of airborne bacteria and predominantly contributed 1.1- to 3.3-μm bacterium-containing particles. Our findings contribute to the development of realistic testing and evaluation schemes for BIODIM equipment by providing information that may be used to simulate operational bioaerosol backgrounds during controlled aerosol chamber-based challenge tests with biological threat agents.

Temporal Variability of the Bioaerosol Background at a Subway Station: Concentration Level, Size Distribution, and Diversity of Airborne Bacteria

Science.gov (United States)

Dybwad, Marius; Skogan, Gunnar

2014-01-01

Naturally occurring bioaerosol environments may present a challenge to biological detection-identification-monitoring (BIODIM) systems aiming at rapid and reliable warning of bioterrorism incidents. One way to improve the operational performance of BIODIM systems is to increase our understanding of relevant bioaerosol backgrounds. Subway stations are enclosed public environments which may be regarded as potential bioterrorism targets. This study provides novel information concerning the temporal variability of the concentration level, size distribution, and diversity of airborne bacteria in a Norwegian subway station. Three different air samplers were used during a 72-h sampling campaign in February 2011. The results suggested that the airborne bacterial environment was stable between days and seasons, while the intraday variability was found to be substantial, although often following a consistent diurnal pattern. The bacterial levels ranged from not detected to 103 CFU m−3 and generally showed increased levels during the daytime compared to the nighttime levels, as well as during rush hours compared to non-rush hours. The airborne bacterial levels showed rapid temporal variation (up to 270-fold) on some occasions, both consistent and inconsistent with the diurnal profile. Airborne bacterium-containing particles were distributed between different sizes for particles of >1.1 μm, although ∼50% were between 1.1 and 3.3 μm. Anthropogenic activities (mainly passengers) were demonstrated as major sources of airborne bacteria and predominantly contributed 1.1- to 3.3-μm bacterium-containing particles. Our findings contribute to the development of realistic testing and evaluation schemes for BIODIM equipment by providing information that may be used to simulate operational bioaerosol backgrounds during controlled aerosol chamber-based challenge tests with biological threat agents. PMID:24162566

Flattening the organization: implementing self-directed work groups.

Science.gov (United States)

Brandon, G M

1996-01-01

In response to tremendous growth of managed care and threats to financial stability and job security, the Greater Baltimore Medical Center (GBMC) restructured itself into independent business units. The radiology department at GBMC resolved to reduce cost per unit-of-service, improve service, determine optimal staffing levels and reduce the number of layers of organization. It was decided to achieve those goals by implementing self-directed work groups. Staff buy-in was critical to success of the project. To begin, the staff was educated intensively about current trends in healthcare, managed care and potential changes in the job market. The radiology department was allowed to reduce the size of its staff through attrition and worked hard to focus staff concern on the impact each individual could have on the bottom line and the resultant effect on job security. Self-directed work groups were designed on a matrix that used small "service teams" in combinations to form larger "work groups." Actual work and daily activities occur at the service team level; information exchange and major decisions occue at the work group level. Seventeen months after beginning the project and 10 months after implementation, the organization has flattened, staff members have adjusted well to new roles, there have been no lay-offs, and the matrix system of small and large groups have proved particularly valuable.

Food Prices and Consumer Demand: Differences across Income Levels and Ethnic Groups

Science.gov (United States)

Ni Mhurchu, Cliona; Eyles, Helen; Schilling, Chris; Yang, Qing; Kaye-Blake, William; Genç, Murat; Blakely, Tony

2013-01-01

Background Targeted food pricing policies may improve population diets. To assess their effects on inequalities, it is important to determine responsiveness to price changes across income levels and ethnic groups. Objective Our goal was to estimate price elasticity (PE) values for major commonly consumed food groups in New Zealand, by income and ethnicity. PE values represent percentage change in demand associated with 1% change in price of that good (own-PE) or another good (cross-PE). Design We used food expenditure data from national household economic surveys in 2007/08 and 2009/10 and Food Price Index data from 2007 and 2010. Adopting an Almost Ideal Demand System approach, own-PE and cross-PE estimates were derived for 24 food categories, household income quintiles, and two ethnic groups (Māori and non-Māori). Results Own-PE estimates (with two exceptions) ranged from −0.44 to −1.78. Cross-PE estimates were generally small; only 31% of absolute values were greater than 0.10. Excluding the outlier ‘energy drinks’, nine of 23 food groups had significantly stronger own-PEs for the lowest versus highest income quintiles (average regression-based difference across food groups −0.30 (95% CI −0.62 to 0.02)). Six own-PEs were significantly stronger among Māori; the average difference for Māori: non-Māori across food groups was −0.26 (95% CI −0.52 to 0.00). Conclusions Food pricing policies have potential to improve population diets. The greater sensitivity of low-income households and Māori to price changes suggests the beneficial effects of such policies on health would be greatest for these groups. PMID:24098408

Reinterpreting between-group inequality

NARCIS (Netherlands)

Elbers, C.T.M.; Lanjouw, P.F.; Mistiaen, J.; Özler, B

2008-01-01

We evaluate observed inequality between population groups against a benchmark of the maximum between-group inequality attainable given the number and relative sizes of those groups under examination. Because our measure is normalized by these parameters, drawing comparisons across different settings

Increased anti-Mullerian hormone levels and ovarian size in a subgroup of women with functional hypothalamic amenorrhea: further identification of the link between polycystic ovary syndrome and functional hypothalamic amenorrhea.

Science.gov (United States)

Carmina, Enrico; Fruzzetti, Franca; Lobo, Roger A

2016-06-01

Functional hypothalamic amenorrhea is a disorder characterized by cessation of menstrual cycles in the absence of organic disease. In most patients, it occurs in adult life after a stressful event and may be related to a condition of mild chronic energy deprivation. The endocrine pattern is characterized by low estrogen levels with an absent response to a progestogen challenge test and low-normal gonadotropin levels. A few studies have shown that some of these women may have some features of polycystic ovary syndrome; these features include an increased androgen response to gonadotropins, increased anti-Mullerian hormone levels, and altered ovarian morphology or increased ovarian size. These findings suggest a link between these 2 completely different disorders: functional hypothalamic amenorrhea and polycystic ovary syndrome. The importance of the possible coexistence of these disorders in some women is important for follow-up of these women and in their treatment if they desire to become pregnant. To determine whether a subgroup of well-characterized women with functional hypothalamic amenorrhea may have the coexistence of polycystic ovary syndrome. Retrospective analysis of women with functional hypothalamic amenorrhea. Forty consecutive patients and 28 normal age-matched control patients were studied. Blood was obtained for serum anti-Mullerian hormone, androgens, and other hormone levels and all women had ovarian ultrasonographic measurements. In the entire group of women with functional hypothalamic amenorrhea, anti-Mullerian hormone and ovarian volume were greater than in control patients. In 13 patients (32.5%), anti-Mullerian hormone was elevated (>4.7 ng/mL, levels consistent with polycystic ovary syndrome) and in this group, ovarian volume was significantly greater than in the remaining patients with functional hypothalamic amenorrhea. Four of the 13 women with functional hypothalamic amenorrhea who had elevated anti-Mullerian hormone levels (10%), also

Group Flow and Group Genius

Science.gov (United States)

Sawyer, Keith

2015-01-01

Keith Sawyer views the spontaneous collaboration of group creativity and improvisation actions as "group flow," which organizations can use to function at optimum levels. Sawyer establishes ideal conditions for group flow: group goals, close listening, complete concentration, being in control, blending egos, equal participation, knowing…

Determination of concentration levels of arsenic, gold and antimony in particle-size fractions of gold ore using Neutron Activation Analysis

International Nuclear Information System (INIS)

Nyarku, M.

2009-02-01

Instrumental Neutron Activation Analysis (INAA) has been used to quantify the concentrations of arsenic, gold and antimony in particle-size fractions of a gold ore. The ore, which was taken from the Ahafo project site of Newmont Ghana Gold Ltd, was first fractionated into fourteen (14) particle-size fractions using state-of-the-art analytical sieve machine. The minimum sieve mesh size used was 36 microns and grains >2000 microns were not considered for analysis. Results of the sieving were analysed with easysieve software. The < 36 microns sub fraction was found to be the optimum, hosting bulk of all three elements. For arsenic, the element was found to be highly concentrated in < 36 to +100 microns size fractions and erratically distributed from +150 microns fraction and above. For gold, in exception of the sub fraction <36 which had exceptionally high concentration, the element is distributed in all the size fractions but slightly 'plays out' in the +150 to +400 microns fractions. Antimony occurrence in the sample was relatively high in <36 microns size fraction followed by 600 - 800, 800 - 1000, 400 - 600 and 36 - 40 microns size fractions in that order. Gold content in the sample was far higher than that of arsenic and antimony. Gold concentration in the composite sample was in the range 564 - 8420 ppm. Arsenic levels were higher as compared to antimony. The range of arsenic concentration in the composite sample was 14.33 - 186.92 ppm. Antimony concentration was in the range 1.09 - 9.48 ppm. (au)

Size-based predictions of food web patterns

DEFF Research Database (Denmark)

Zhang, Lai; Hartvig, Martin; Knudsen, Kim

2014-01-01

We employ size-based theoretical arguments to derive simple analytic predictions of ecological patterns and properties of natural communities: size-spectrum exponent, maximum trophic level, and susceptibility to invasive species. The predictions are brought about by assuming that an infinite number...... of species are continuously distributed on a size-trait axis. It is, however, an open question whether such predictions are valid for a food web with a finite number of species embedded in a network structure. We address this question by comparing the size-based predictions to results from dynamic food web...... simulations with varying species richness. To this end, we develop a new size- and trait-based food web model that can be simplified into an analytically solvable size-based model. We confirm existing solutions for the size distribution and derive novel predictions for maximum trophic level and invasion...

Meaningful Effect Sizes, Intraclass Correlations, and Proportions of Variance Explained by Covariates for Planning Two- and Three-Level Cluster Randomized Trials of Social and Behavioral Outcomes.

Science.gov (United States)

Dong, Nianbo; Reinke, Wendy M; Herman, Keith C; Bradshaw, Catherine P; Murray, Desiree W

2016-09-30

There is a need for greater guidance regarding design parameters and empirical benchmarks for social and behavioral outcomes to inform assumptions in the design and interpretation of cluster randomized trials (CRTs). We calculated the empirical reference values on critical research design parameters associated with statistical power for children's social and behavioral outcomes, including effect sizes, intraclass correlations (ICCs), and proportions of variance explained by a covariate at different levels (R 2 ). Children from kindergarten to Grade 5 in the samples from four large CRTs evaluating the effectiveness of two classroom- and two school-level preventive interventions. Teacher ratings of students' social and behavioral outcomes using the Teacher Observation of Classroom Adaptation-Checklist and the Social Competence Scale-Teacher. Two types of effect size benchmarks were calculated: (1) normative expectations for change and (2) policy-relevant demographic performance gaps. The ICCs and R 2 were calculated using two-level hierarchical linear modeling (HLM), where students are nested within schools, and three-level HLM, where students were nested within classrooms, and classrooms were nested within schools. Comprehensive tables of benchmarks and ICC values are provided to inform prevention researchers in interpreting the effect size of interventions and conduct power analyses for designing CRTs of children's social and behavioral outcomes. The discussion also provides a demonstration for how to use the parameter reference values provided in this article to calculate the sample size for two- and three-level CRTs designs. © The Author(s) 2016.

Psacoin level 1A intercomparison probabilistic system assessment code (PSAC) user group

International Nuclear Information System (INIS)

Nies, A.; Laurens, J.M.; Galson, D.A.; Webster, S.

1990-01-01

This report describes an international code intercomparison exercise conducted by the NEA Probabilistic System Assessment Code (PSAC) User Group. The PSACOIN Level 1A exercise is the third of a series designed to contribute to the verification of probabilistic codes that may be used in assessing the safety of radioactive waste disposal systems or concepts. Level 1A is based on a more realistic system model than that used in the two previous exercises, and involves deep geological disposal concepts with a relatively complex structure of the repository vault. The report compares results and draws conclusions with regard to the use of different modelling approaches and the possible importance to safety of various processes within and around a deep geological repository. In particular, the relative significance of model uncertainty and data variability is discussed

Power and sample-size estimation for microbiome studies using pairwise distances and PERMANOVA.

Science.gov (United States)

Kelly, Brendan J; Gross, Robert; Bittinger, Kyle; Sherrill-Mix, Scott; Lewis, James D; Collman, Ronald G; Bushman, Frederic D; Li, Hongzhe

2015-08-01

The variation in community composition between microbiome samples, termed beta diversity, can be measured by pairwise distance based on either presence-absence or quantitative species abundance data. PERMANOVA, a permutation-based extension of multivariate analysis of variance to a matrix of pairwise distances, partitions within-group and between-group distances to permit assessment of the effect of an exposure or intervention (grouping factor) upon the sampled microbiome. Within-group distance and exposure/intervention effect size must be accurately modeled to estimate statistical power for a microbiome study that will be analyzed with pairwise distances and PERMANOVA. We present a framework for PERMANOVA power estimation tailored to marker-gene microbiome studies that will be analyzed by pairwise distances, which includes: (i) a novel method for distance matrix simulation that permits modeling of within-group pairwise distances according to pre-specified population parameters; (ii) a method to incorporate effects of different sizes within the simulated distance matrix; (iii) a simulation-based method for estimating PERMANOVA power from simulated distance matrices; and (iv) an R statistical software package that implements the above. Matrices of pairwise distances can be efficiently simulated to satisfy the triangle inequality and incorporate group-level effects, which are quantified by the adjusted coefficient of determination, omega-squared (ω2). From simulated distance matrices, available PERMANOVA power or necessary sample size can be estimated for a planned microbiome study. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Organic matter content and particle size modifications in mangrove sediments as responses to sea level rise.

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Sanders, Christian J; Smoak, Joseph M; Waters, Mathew N; Sanders, Luciana M; Brandini, Nilva; Patchineelam, Sambasiva R

2012-06-01

Mangroves sediments contain large reservoirs of organic material (OM) as mangrove ecosystems produce large quantities and rapidly burial OM. Sediment accumulation rates of approximately 2.0 mm year(-1), based on (210)Pb(ex) dating, were estimated at the margin of two well-developed mangrove forest in southern Brazil. Regional data point to a relative sea level (RSL) rise of up to ∼4.0 mm year(-1). This RSL rise in turn, may directly influence the origin and quantity of organic matter (OM) deposited along mangrove sediments. Lithostratigraphic changes show that sand deposition is replacing the mud (<63 μm) fraction and OM content is decreasing in successively younger sediments. Sediment accumulation in coastal areas that are not keeping pace with sea level rise is potentially conducive to the observed shifts in particle size and OM content. Copyright © 2012 Elsevier Ltd. All rights reserved.

An evaluation of portion size estimation aids: Consumer perspectives on their effectiveness.

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Faulkner, Gemma P; Livingstone, M Barbara E; Pourshahidi, L Kirsty; Spence, Michelle; Dean, Moira; O'Brien, Sinead; Gibney, Eileen R; Wallace, Julie M W; McCaffrey, Tracy A; Kerr, Maeve A

2017-07-01

This qualitative study aimed to investigate consumer opinions on the usefulness of portion size estimation aids (PSEA); consumer preferences in terms of format and context for use; and the level of detail of guidance considered necessary for the effective application of PSEA. Six focus groups (three to eight participants per group) were conducted to elicit views on PSEA. The discussions were recorded, transcribed verbatim and analysed by two independent researchers using a template approach. The focus groups were conducted in 2013 by an experienced moderator in various sites across the island of Ireland (three in the Republic of Ireland and three in Northern Ireland) including local leisure, community and resource centres; the home environment; and a university meeting room. General population, males (n = 17) and females (n = 15) aged 18-64 years old. Participants were recruited from both urban and rural locations representing a range of socio-economic groups. The majority of participants deemed the coloured portion pots and disposable plastic cup (household measures) to be useful particularly for the estimation of amorphous cereal products (e.g. breakfast cereals). Preferences were evident for "visual" PSEA (reference objects, household measures and food packaging) rather than 'quantities and measures' such as weighing in grams or ounces. Participants stated that PS education should be concise, consistent, from a reputable source, initiated at school age and communicated innovatively e.g. mobile app or TV advertisement. Guidance in relation to gender, age and activity level was favoured over a "one size fits all" approach. This study identified consumer preferences and acceptance of "visual" PSEA such as portion pots/cups to estimate appropriate PS of amorphous grain foods such as breakfast cereals, pasta and rice. Concise information from a reputable source in relation to gender, age and activity level should accompany PSEA. Copyright © 2017 Elsevier Ltd

The effect of group composition on the welfare of African catfish (Clarias gariepinus)

NARCIS (Netherlands)

Martins, C.I.; Schrama, J.W.; Verreth, J.A.J.

2006-01-01

Within fish farming grading, i.e. the process of sorting to approximate size, changes the group composition from heterogeneous to homogeneous. Although this procedure is considered an acute stressor, the long-term consequences of grading on aggression and stress levels have not yet been

Size acceptance and intuitive eating improve health for obese, female chronic dieters.

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Bacon, Linda; Stern, Judith S; Van Loan, Marta D; Keim, Nancy L

2005-06-01

Examine a model that encourages health at every size as opposed to weight loss. The health at every size concept supports homeostatic regulation and eating intuitively (ie, in response to internal cues of hunger, satiety, and appetite). Six-month, randomized clinical trial; 2-year follow-up. White, obese, female chronic dieters, aged 30 to 45 years (N=78). Free-living, general community. Six months of weekly group intervention (health at every size program or diet program), followed by 6 months of monthly aftercare group support. Anthropometry (weight, body mass index), metabolic fitness (blood pressure, blood lipids), energy expenditure, eating behavior (restraint, eating disorder pathology), and psychology (self-esteem, depression, body image). Attrition, attendance, and participant evaluations of treatment helpfulness were also monitored. Analysis of variance. Cognitive restraint decreased in the health at every size group and increased in the diet group, indicating that both groups implemented their programs. Attrition (6 months) was high in the diet group (41%), compared with 8% in the health at every size group. Fifty percent of both groups returned for 2-year evaluation. Health at every size group members maintained weight, improved in all outcome variables, and sustained improvements. Diet group participants lost weight and showed initial improvement in many variables at 1 year; weight was regained and little improvement was sustained. The health at every size approach enabled participants to maintain long-term behavior change; the diet approach did not. Encouraging size acceptance, reduction in dieting behavior, and heightened awareness and response to body signals resulted in improved health risk indicators for obese women.

Images of Stakeholder Groups Based on Their Environmental Sustainability Linked CSR Projects: A Meta-Analytic Review of Korean Sport Literature

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Hyun-Duck Kim

2017-09-01

Full Text Available Achieving sustainability in sports events requires effective management, political leadership, and ensuring that all stakeholders adhere to a sustainable philosophy. In order to stage a mega-event, tremendous infrastructure and construction are required with significant consumption of private and public resources. Multiple stakeholder groups are recognized as key entities responsible for an efficient trigger of a mega-event. The aim of this study is to conduct a systematic review of Korean sport literature with regard to CSR practices (ES-linked of different stakeholder groups and examine through a meta-analytic methodology their impact on the “images” of these groups. The CMA program was utilized as the main analysis tool to calculate the effect sizes from the selected empirical studies. The results indicated that CSR performance of governmental organizations had the highest effect size level on their own image (brand identity as perceived by visitors and participants. Among the stakeholder groups, effect size levels of their CSR performances were followed by those of corporate sponsors and professional teams. It was found that stakeholder groups are pressured to maintain a balance between financial performance, consumer well-being, and brand identity to bring in external investment.

Genome size evolution in Ontario ferns (Polypodiidae): evolutionary correlations with cell size, spore size, and habitat type and an absence of genome downsizing.

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Henry, Thomas A; Bainard, Jillian D; Newmaster, Steven G

2014-10-01

Genome size is known to correlate with a number of traits in angiosperms, but less is known about the phenotypic correlates of genome size in ferns. We explored genome size variation in relation to a suite of morphological and ecological traits in ferns. Thirty-six fern taxa were collected from wild populations in Ontario, Canada. 2C DNA content was measured using flow cytometry. We tested for genome downsizing following polyploidy using a phylogenetic comparative analysis to explore the correlation between 1Cx DNA content and ploidy. There was no compelling evidence for the occurrence of widespread genome downsizing during the evolution of Ontario ferns. The relationship between genome size and 11 morphological and ecological traits was explored using a phylogenetic principal component regression analysis. Genome size was found to be significantly associated with cell size, spore size, spore type, and habitat type. These results are timely as past and recent studies have found conflicting support for the association between ploidy/genome size and spore size in fern polyploid complexes; this study represents the first comparative analysis of the trend across a broad taxonomic group of ferns.

Urbanization level and woodland size are major drivers of woodpecker species richness and abundance.

Directory of Open Access Journals (Sweden)

Lukasz Myczko

Full Text Available Urbanization is a process globally responsible for loss of biodiversity and for biological homogenization. Urbanization may have a direct negative impact on species behaviour and indirect effects on species populations through alterations of their habitats, for example patch size and habitat quality. Woodpeckers are species potentially susceptible to urbanization. These birds are mostly forest specialists and the development of urban areas in former forests may be an important factor influencing their richness and abundance, but documented examples are rare. In this study we investigated how woodpeckers responded to changes in forest habitats as a consequence of urbanization, namely size and isolation of habitat patches, and other within-patch characteristics. We selected 42 woodland patches in a gradient from a semi-natural rural landscape to the city centre of Poznań (Western Poland in spring 2010. Both species richness and abundance of woodpeckers correlated positively to woodland patch area and negatively to increasing urbanization. Abundance of woodpeckers was also positively correlated with shrub cover and percentage of deciduous tree species. Furthermore, species richness and abundance of woodpeckers were highest at moderate values of canopy openness. Ordination analyses confirmed that urbanization level and woodland patch area were variables contributing most to species abundance in the woodpecker community. Similar results were obtained in presence-absence models for particular species. Thus, to sustain woodpecker species within cities it is important to keep woodland patches large, multi-layered and rich in deciduous tree species.

Urbanization level and woodland size are major drivers of woodpecker species richness and abundance.

Science.gov (United States)

Myczko, Lukasz; Rosin, Zuzanna M; Skórka, Piotr; Tryjanowski, Piotr

2014-01-01

Urbanization is a process globally responsible for loss of biodiversity and for biological homogenization. Urbanization may have a direct negative impact on species behaviour and indirect effects on species populations through alterations of their habitats, for example patch size and habitat quality. Woodpeckers are species potentially susceptible to urbanization. These birds are mostly forest specialists and the development of urban areas in former forests may be an important factor influencing their richness and abundance, but documented examples are rare. In this study we investigated how woodpeckers responded to changes in forest habitats as a consequence of urbanization, namely size and isolation of habitat patches, and other within-patch characteristics. We selected 42 woodland patches in a gradient from a semi-natural rural landscape to the city centre of Poznań (Western Poland) in spring 2010. Both species richness and abundance of woodpeckers correlated positively to woodland patch area and negatively to increasing urbanization. Abundance of woodpeckers was also positively correlated with shrub cover and percentage of deciduous tree species. Furthermore, species richness and abundance of woodpeckers were highest at moderate values of canopy openness. Ordination analyses confirmed that urbanization level and woodland patch area were variables contributing most to species abundance in the woodpecker community. Similar results were obtained in presence-absence models for particular species. Thus, to sustain woodpecker species within cities it is important to keep woodland patches large, multi-layered and rich in deciduous tree species.

Making Cooperative Learning Groups Work.

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Hawley, James; De Jong, Cherie

1995-01-01

Discusses the use of cooperative-learning groups with middle school students. Describes cooperative-learning techniques, including group roles, peer evaluation, and observation and monitoring. Considers grouping options, including group size and configuration, dyads, the think-pair-share lecture, student teams achievement divisions, jigsaw groups,…

Distraction sneakers decrease the expected level of aggression within groups: a game-theoretic model.

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Dubois, Frédérique; Giraldeau, Luc-Alain; Hamilton, Ian M; Grant, James W A; Lefebvre, Louis

2004-08-01

Hawk-dove games have been extensively used to predict the conditions under which group-living animals should defend their resources against potential usurpers. Typically, game-theoretic models on aggression consider that resource defense may entail energetic and injury costs. However, intruders may also take advantage of owners who are busy fighting to sneak access to unguarded resources, imposing thereby an additional cost on the use of the escalated hawk strategy. In this article we modify the two-strategy hawk-dove game into a three-strategy hawk-dove-sneaker game that incorporates a distraction-sneaking tactic, allowing us to explore its consequences on the expected level of aggression within groups. Our model predicts a lower proportion of hawks and hence lower frequencies of aggressive interactions within groups than do previous two-strategy hawk-dove games. The extent to which distraction sneakers decrease the frequency of aggression within groups, however, depends on whether they search only for opportunities to join resources uncovered by other group members or for both unchallenged resources and opportunities to usurp.

The impact of size of cooperative group on achievement, social support, and self-esteem.

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Bertucci, Andrea; Conte, Stella; Johnson, David W; Johnson, Roger T

2010-01-01

The effect of cooperative learning in pairs and groups of 4 and in individualistic learning were compared on achievement, social support, and self-esteem. Sixty-two Italian 7th-grade students with no previous experience with cooperative learning were assigned to conditions on a stratified random basis controlling for ability, gender, and self-esteem. Students participated in 1 instructional unit for 90 min for 6 instructional days during a period of about 6 weeks. The results indicate that cooperative learning in pairs and 4s promoted higher achievement and greater academic support from peers than did individualistic learning. Students working in pairs developed a higher level of social self-esteem than did students learning in the other conditions.

Clinical importance of angiogenic cytokines, fibrinolytic activity and effusion size in parapneumonic effusions.